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    1. Reviewer #2 (Public Review):

      The manuscript documents a thorough and well-validated clinical prediction model for risk of severe child linear growth faltering after diarrheal disease episodes, using data from multiple studies and countries. They identified a parsimonious model of child age and current size with relatively good predictive accuracy. However, I don't believe the prediction rule should be used in it's current form due to the outcome used the danger of missing treating children who require nutritional supplementation.

      The outcome used for prediction in a binary indicatory for a decrease in height-for-age Z-score >= 0.5. A child who fails to gain height by future measurements is of concern, but this outcome also misses children who are already experiencing growth failure, and is vulnerable to regression to the mean effect. The two most important predictors were age and current size, with current size having a positive association with risk of growth faltering. As mentioned in the discussion, there is "the possibility that children need to have high enough HAZ in order to have the potential to falter." Additionally, there may be children with erroneously high height measurements at the first measurement, so that the HAZ change >= 0.5 associated with high baseline HAZ is from measurement-error regression to the mean. I recommend also predicting absolute HAZ (or stunting status) as a secondary outcome and comparing if the important predictors change.

      In its current form, the results and conclusions from the results have problematic implications for the treatment of child malnutrition. The conclusion states: "In settings with high mortality and morbidity in early childhood, such tools could represent a cost-effective way to target resources towards those who need it most." If the current CPR was used in a resource-constrained setting, it would recommend that larger children should be prioritized for nutritional supplementation over already stunted children who may have reached their growth faltering floor. In addition, with a sensitivity of 80%, the tool would miss treating a large number of children who would experience growth faltering. The results of the clinical prediction tool need to be presented with care in how it could be used to prioritize treatment without missing treating children who would benefit from nutritional supplementation. Including absolute HAZ as an outcome will help, along with additional discussion of how the CPR fits alongside current treatment recommendations. For example, does this rule indicate treating children who aren't currently treated, or are there children who don't need treatment given current guidelines and the created CPR.

      In sum, this is a thorough, well done, clearly explained exercise in creating a clinical prediction tool for predicting child risk of future growth faltering. The writing and motivation is clear, and the methods have applicability far beyond the specific use-case.

    1. Reviewer #2 (Public Review):

      The authors investigate whether neuronal activity-regulated transcription factor 4 (NPAS4) in the medial prefrontal cortex (mPFC) is involved in stress-induced effects on neuronal spine synapse density (as a proxy for synaptic activity) and reward behaviors. A major strength of the manuscript is that NPAS4 is shown to be necessary for stress-induced reward deficits and pyramidal neuron spine density. In addition, whole transcriptome analysis of NPAS4 target genes identify a number of genes previously found to be regulated in the postmortem brain of humans with MDD, providing translational relevance to these studies. A weakness is that studies were only performed in male mice so its unclear how generalizable these effects are to females. Despite this, the work will likely impact the field of neuropsychiatry by providing novel information about the molecular and cellular mechanisms in mPFC responsible for stress-induced effects on spines synapses and reward behaviors.

    1. Reviewer #2 (Public Review):

      In this paper, Osei-Owusu uses a combination of electrophysiology, structure-guided mutagenesis, and molecular dynamics to understand the desensitization of the proton-activated chloride channel (PAC). They show the extent and rate of desensitization is pH-dependent with lower pH promoting faster and more complete desensitization. They identify multiple residues with important roles in desensitization in two clusters at the extracellular end of TM1 and at the interface between the transmembrane and extracellular domains. Together with previously determined structures, the authors offer a model in which interactions between these residues play key roles in stabilizing the desensitized over the open conformation. This work provides important molecular insight into molecular mechanisms underlying the function of this widely expressed ion channel.

    1. Reviewer #2 (Public Review):

      This is a well-thought-out, clearly exposed article. It builds upon the platform of 'original antigenic sin' (OAS), a notion first developed from studying individuals infected with influenza. According to OAS, the initial infection will set the dominant immune response targets (antigens) that immune cells will recognize, such that infection with a related strain will cause a strong response focused mainly against the initially infecting strain, that then goes on to protect against the new-infecting strain. This study builds off this idea, showing that as strains become increasingly antigenically distant as inferred by the time between strain appearance, the cross-protection can drop to a point where it needs to be invigorated with a potentially new response. The potential biological mechanisms behind this aren't discussed, but a model is built that conveys the potential for 'relative risk' of an individual over the course of the life, based essentially on when one was born.

      The basic premise was to measure from serum influenza haemagglutinin-inhibition (HI) titers of 21 strains of influenza A (H3N2) - related strains causing disease at various times over a period of some 40 years- from a diverse set of ≈800 participants of various ages, at two time points, spaced 2 yr apart. The authors then calculated the HI titer for the 21 strains for each individual. From this, each participant's age, their age at the time of a strain's development, and when a strain emerged were used to assess whether there was periodicity to immune responses by performing a splined Fourier transform for each individual and then examining the composite pattern across time for HI titers. The authors propose that on average there is a 24-year periodicity to immune responses to influenza strains, such that after the initial infection, cross-reactivity reduces to the point where it may be less meaningful for protection over around 24-year, and suggests activation of a 'new' immune response might be required to control the more distant strain involved in the response at that time. The periodicity was longer than would be predicted if age were not a factor involved in the HI titer patterns across time. Further, variability in the periodicity was shown to involve broad cross-reactivity between strains and narrow cross-reactivity in more highly-related (closer in time) strains, individual HI titer, and periodic population fluctuations. In the literature, viral strains are estimated to mutate to the point of losing 50% cross-reactivity with a T1/2 of approximately 2.5 yr, which would make the inferred lifespan plausible but perhaps surprisingly long, implying there are immune feedback parameters that influence periodicity. The authors also use an independent cohort of approximately 150 individuals from a separate, published, study to validate some findings revealed in the primary data set.

      Strengths: Overall, the study is well executed and the patterns that are visually apparent in Figure 1A (the 'raw' data) are built on to inform a model of the potential breadth of cross-reactivity in a given individual at any given time after birth, integrated with the influenza strains to which they are most likely to have been first exposed. It is a complex thing to make sense of data involving many individuals who could be infected or vaccinated at any and variable points in time over the course of their life, but the authors derive a model that probabilistically accounts for possible infection events, so controls for this nicely, or at least to a degree that is practicable.

      Questions related to the main limitation: The level of math in this paper makes it hard for a basic biologist to critique the approach, but the argued points are intriguing. Foremost, in the final part of the paper the authors move from building a model to testing its potential to predict HI titers in the final quarter strains of the study period, placing individuals into one of four phases: I) early increasing to high titer response, II) waning response phase where they are returning back to the average population-level response against a strain, III) sub-par response against a strain and then reinitiation of HI titers in phase IV. Pleasingly this shows a good correlation between individuals' ages and their predicted phase. However, while the fit predicts phase well in Fig 4C and 4D, it looks to perform less adequately in Fig 4B.

      Q1: Why is this?

      Another point for consideration is that the time between samplings (2010-2012) is comparatively short, given a 24-yr predicted periodicity. Q2: What would happen to the predictions if the periodicity were 35-yr or 6-yr? Would the model fail to call individuals accurately in these cases?

      Q3: Similarly, if the samples were taken further apart, would the model still be effective at predicting phase?

    1. Reviewer #2 (Public Review):

      In their manuscript titled "Feature detecting columnar neurons mediate object tracking saccades in Drosophila", Frighetto & Frye study the effect manipulating T3 neurons has on tethered flight saccades. The authors first characterize the responses of T3 neurons to simple visual stimuli, and then manipulate T3 cells (with both Kir2.1 and CsCrimson) and study the effects on the fly's tethered flight behavior, focusing on different types of sharp turns (saccades). Finally, the authors suggest an integrate and fire model to explain how an array of T3-like neurons can produce some of the recorded behavior.

      The authors study the elementary, yet challenging, computation of object discrimination. They hone in on a cell type that most likely plays an important role in the circuit. However, the authors do not sufficiently clarify the framework in which they conceptualize T3's role in object discrimination, neither when discussing it in the introduction/discussion nor when explaining experimental results. The authors present the work in comparison to T4/T5 cells. However, T4/T5 cells have been shown to be both local motion detectors and the main cell types to compute motion in the fly's eye. Downstream neurons integrate over these local units to detect different patterns of global and local motion (Authors should cite Krapp 1996 Nature). Are the authors suggesting that T3 neurons perform a similar function only as local object detectors? That is a bold claim that will need to be supported with more experimental results and reconciled with previous results. We already know of other Lobula Columnar neurons (LCs) that respond to different sizes, some even smaller than the optimal T3 stimulus (e.g. Klapoetke 2022 Neuron) and we know of LCs that respond to small objects that do not receive major inputs from T3 cells (e.g. Hindmarsh 2021 Nature).

      These differences between T4/T5 cells and T3s also make interpreting the experimental manipulations more challenging. When hyperpolarizing T4/T5 or 'blinding' them with CsCrimson activation, the visual motion circuit is severely disrupted. However, the same cannot be said about inactivating/blinding T3 neurons and the object detection circuit (if it is indeed a single circuit). The authors are justified in deducing a connection between blocking T3 neurons and a reduction in bar tracking, but generalizing the results to object detection requires more experiments and clarifications.

      When framing the manuscript in the object detection framework, previous results regarding the definition of an object should also be addressed. Maimon Curr. Biol. 2008 and work from their own lab (Mongeau, 2019) have already shown that tethered flies respond differently to bars and small objects (fixating on the former while anti-fixating on the latter). Previous work has also shown that T3 neurons respond strongly to small objects and suppress responses to long bars (Tanaka Curr. Biol. 2020). Since all the behavioral experiments in the current manuscript and all the visual stimuli are full arena-length bars, it is impossible to tell whether the T3 results generalize to small objects and even how to reconcile the stronger response to small objects with the role ascribed to T3 cells in generating behavioral responses to long bars.

      Finally, the authors propose a model for a hypothetical neuron downstream of T3 that would integrate over several T3s and generate saccades. However, given the current knowledge level in the fly vision field, the model should either be grounded more in actual circuit connectivity or produce testable predictions that would guide further research.

      The authors should decide whether they would like to address these concerns with more specific experiments that would shed light on the role T3 has to play under different conditions and different definitions of a visual object, or whether they would prefer to limit the scope of their claims.

    1. Reviewer #2 (Public Review):

      The burden of cervical cancer worldwide is well recognized. While prevention strategies, including vaccination against human papillomavirus (HPV), cervical cancer screening, and pre-cancer treatment, can reduce the burden of cervical cancer, access to these measures is still limited, especially in low- and middle-income countries. Since the impact of prevention strategies is heavily dependent on the disease's burden on a particular population, we need to know the latter to assess the impact of these context-specific prevention strategies.

      However, epidemiological data on cervical cancer are not always available for all geographical areas. This paper uses India as a case study to propose a framework called "Footprinting" to comprehensively evaluate the burden of cervical cancer. The authors applied a three-step analytical strategy to impute cervical cancer epidemiological data in states where this information was unavailable using data from cervical cancer incidence, HPV prevalence, and sexual behaviour from other regions. The findings suggest a high and low incidence of cervical cancer incidence in different parts of India; all Indian states with missing data were classified as low incidence.

      The proposed analytical strategy presents an important solution for imputing data from geographic areas of a country where data are missing.

      One conceptual limitation of this work is the lack of explanation or evidence that sexual behaviour can be used to approximate cervical cancer and/or HPV rates. Also, full information on the three main indicators is only available in two states. This is used to impute the values for the other states. Moreover, the available data used in this study also present some limitations; for example, cervical cancer incidence data were from 2012 to 2016, while sex behaviour data were from 2006. This large gap is likely to have a significant cohort effect, especially given changes in sexual norms in Western countries over the last few decades, which may have gradually influenced other countries, especially in this age of the internet and social media. Finally, it would be interesting to validate this methodology to confirm its utility.

      The proposed framework's strength is difficult to evaluate because the steps and justification for the model variables were not clearly presented, nor were the models validated. Based on the authors' interpretation of the framework findings, this framework may help extrapolate data from one country to another. I'm curious as to whether this framework could be applied across states and countries.

    1. Reviewer #2 (Public Review):

      The objective of this work by Masschelin et al. is to investigate the physiological relevance of flavin adenine dinucleotide (FAD). In particular, FAD supports the activity of flavoproteins involved in the production of cellular energy. Mutations in genes encoding flavoproteins often are associated with inborn errors of metabolism (IEMs), thus the clinical interest in investigating in more depth the physiological role of FAD. In this study, the authors first subjected male mice to a vitamin B12 deficient diet (B2D), demonstrating that loss of B12 replicates the phenotypes often observed with IEMs, including loss of body weight, hypoglycemia, and fatty liver. Using a combination of metabolomic phenotyping, transcriptomic analyses, and pharmacology (treatment with fenofibrate, a PPARa agonist), the authors then reach the general conclusion that activation of the nuclear receptor PPARa can rescue the B2D phenotypes, thus revealing that PPARa directly controls the metabolic responses to FAD availability. Although the phenotypic analysis of the mice subjected to B2D increases our knowledge of the physiological impact of depleting the FAD pools on global energy metabolism, not all conclusions and statements made by the authors are totally supported by the data. In particular, the study is overall too descriptive and lacks mechanistic insights. While PPARa is likely an important player in the metabolic response to FAD availability, the molecular details on how FAD controls the activity of PPARa either directly or indirectly are entirely missing. Therefore, the authors are encouraged to directly assess whether B2D directly influences PPARa activity on the genes identified in the study, perform rescue experiments in the liver of PPARa KO mice and explore the possibility that other factors (including nuclear receptors) also participate in the response to B12 deficiency and diminished FAD pools.

    1. Reviewer #2 (Public Review):

      This is a nice study that uses cutting-edge MRI measurements in the context of a carefully designed visual experiment. The data would seem to be of high quality and in general, the approach is promising for opening up avenues for non-invasive measurements of cortical myelination.

      Unfortunately, this particular study seems to fall into an unhappy middle ground in terms of the conclusions that can be drawn: the relaxometry measures lack the specificity to be considered "ground truth", while the authors claim that the literature lacks consensus regarding the structures that are being studied. The authors propose that their results resolve whether or not stripes differ in their patterns of myelination, but R1 lacks the specificity to do this. While myelin is a primary driver of relaxation times in cortex, relaxometry cannot be considered to be specific to myelin. It is possible that the small observed changes in R1 are driven by myelin, but they could also reflect other tissue constituents, particularly given the small observed effect sizes. If the literature was clear on the pattern of myelination across stripes, this study could confirm that R1 measurements are sensitive to and consistent with this pattern. But the authors present the work as resolving the question of how myelination differs between stripes, which over-reaches what is possible with this method. As it stands, the measured differences in R1 between functionally-defined cortical regions are interesting, but require further validation (e.g., using invasive myelin staining).

      Moreover, the results make clear that R1 differences are not sufficiently strong to provide an independent measure of this structure (e.g., for segmentation of stripe). As such, one would still require fMRI to localise stripes, making it unclear what role R1 measures would play in future studies.

      The Introduction concludes with the statement that "Whereas recent studies have explored cortical myelination ... using non-quantitative, weighted MR images... we showed for the first time myelination differences using MRI on a quantitative basis". As written, this sentence implies that others have demonstrated that simpler non-quantitative imaging can achieve the same aims as qMRI. Simply showing that a given method is able to achieve an aim would not be sufficient: the authors should demonstrate that this constitutes an important advance.

      The study includes a very small number of participants (n=4). The advantage of non-invasive in-vivo measurements, despite the fact that they are indirect measures, should be that one can study a reasonable number of subjects. So this low n seems to undermine that point. I rarely suggest additional data collection, but I do feel that a few more subjects would shore up the study's impact.

      The paper overstates what can be concluded in a number of places. For example, the paper suggests that R1 and R2* are highly-specific to myelin in a number of places. For example, on p7 the text reads" "We tested whether different stripe types are differentially myelinated by comparing R1 and R2*..." Relaxation times lack the specificity to definitively attribute these changes purely to myelin. Similarly, on p11: "Our study showed that pale stripes which exhibit lower oxidative metabolic activity according to staining with CO are stronger myelinated than surrounding gray matter in V2." This implies that the study directly links CO staining to myelination. In addition to using non-specific estimates of myelination, the study does not actually measure CO.

      I'm confused by the analysis in Figure 5. I can appreciate why the authors are keen to present a "tripartite" analysis (thick, thin, and pale stripes). But I find the gray curves confusing. As I understand it, the gray curves as generated include both the stripe of interest (red or blue plots) and the pale stripes. Why not just generate a three-way classification? Generating these plots in effect has already required hard classification of thin and thick stripes, so it is odd to create the gray plots, which mix two types of stripes. Alternatively, could you explicitly model the partial volume for a given cortical location (e.g., under the assumption that partial volume of thick and thin strips is indicated by the z-score) for the corresponding functional contrast? One could then estimate the relaxation times as a simple weighted sum of stripe-wise R1 or R2.

    1. RRID: ZFIN ID: ZDB-GENO-060619–2

      DOI: 10.1523/ENEURO.0020-22.2022

      Resource: (ZFIN Cat# ZDB-GENO-060619-2,RRID:ZFIN_ZDB-GENO-060619-2)

      Curator: @sofiakhan13

      SciCrunch record: RRID:ZFIN_ZDB-GENO-060619-2

      What is this?

    1. Reviewer #2 (Public Review):

      This paper is a technical tour de force and provides interesting results. This group has indeed contributed to the understanding of membrane potential and firing dynamics of different cortical neuron subclasses during sensation in various previous papers. Yet, the paper falls short in providing a cohesive conclusion and interpretation of their results on pyramidal neurons, PV, SST, and VIP cells in response to free whisking and active touch at different cortical depths. The authors clearly claim that this manuscript aims to extend the current knowledge by investigating Vm dynamics of pyramidal neurons and various GABAergic subtypes across a greater range of cortical depths. The major shortcoming of this paper is indeed a lack of a clear conclusion or picture of how different cortical neuron types are engaged by different states. Overall, I struggle to find a novel message emerging from the present manuscript that hasn't already been described by the same lab. And this is a pity, as the experiments are of the highest quality and the data is definitely hard-won.

    1. Reviewer #2 (Public Review):

      Proton-activated chloride channel (PAC or ASOR) is a newly discovered anion channel which has a broad tissue expression and is implicated in important physiological processes, such as regulation of endosomal acidification and macropinocytosis. PAC is also implicated in pathological conditions related to acidosis on the plasma membrane. Since its discovery and initial characterization, several structures were solved in resting, activated and desensitized states, revealing an overall channel architecture and its mechanism of action. However, little is known about modulation of PAC channel by endogenous molecules. In the present manuscript, the authors sought to explore the modulation of PAC by lipids, particularly by PIP2, as this lipid is known to modulate numerous unrelated membrane proteins.

      The major strength of the manuscript is the variety of approaches which the authors implement to characterize the mechanism of modulation of PAC by PIP2. Firstly, the authors demonstrate that PIP2 inhibits PAC channel if applied extracellularly. Furthermore, the authors demonstrate that PIP2 acts on the activated/poised towards desensitization, and not on the resting state of the channel. To explore the effect further, the authors tested various PIP molecules, varying in the number of phosphates in the inositol headgroup, and the length of acyl chains. The inhibition of PAC was more potent with the increase of the number of phosphates, and with the lengthening of acyl chains. The lipid chain without inositol, or the inositol without acyl chains, were not as potent in inhibiting PAC. The authors conclude that inositol headgroup together with acyl chains of at least 8 carbons in length are both required to potently inhibit PAC.

      To investigate the potential PIP2 binding site, the authors proceeded to solve the structure of PAC in complex with PIP2. Surprisingly, a density representing a putative PIP2 molecule is found on the extracellular side of the protein. This is a rather unusual finding, given that PIP2 is mostly localized to the inner leaflet of the plasma membrane. To further confirm the binding of PIP2 molecule to this site, the authors mutate the residues interacting with PIP2 molecule in their structure, and observe the decrease in inhibition of the channel by PIP2. Furthermore, the authors observe that these residues are not conserved in all PAC homologs. D. rerio PAC channel does not have these residues and is not inhibited by PIP2 as potently as the human homolog (hPAC). Introducing equivalent residues in D. rerio PAC channel endowed it with modulation by PIP2, similar to hPAC, further strengthening the conclusion that the identified site indeed binds PIP2.

      Overall, the authors succeeded in identifying and characterizing an endogenous molecule with the potential to modulate PAC channel. The present study is the first case of identifying a modulator, characterizing its binding site and mechanism of action on PAC channel. This opens new exciting avenues for structure-guided drug design for this newly-discovered ion channel. However, the localization of the PIP2 binding site to the outer membrane leaflet is quite unexpected, and it is unclear if PAC could be modulated by PIP2 in a physiological context and whether this would be mediated by another lipid transporter. The work will be of interest to ion channel field and a broader membrane protein community with the emphasis on lipid modulation of membrane proteins.

    1. Reviewer #2 (Public Review):

      I would like to congratulate the authors for testing the hypothesis that the gut microbiome from animals that lack myostatin is sufficient to improve muscle-related measures (except treadmill running time). Subsequent experiments should examine if the identified bacteria are sufficient, on their own, to impact muscle, which may open the field to muscle-improving probiotics. Alternatively, data for the SCFA, valerate, may foster approaches aimed at improving muscle with SCFA supplementation. RCTs are needed to test these hypotheses.

      Strengths include a translational approach, including findings in pigs, in colonized mice, and in cells.

      Weaknesses include the need to normalize muscle-related measures to body weight. Is muscle mass increased, for example, when divided by body weight? If not it would argue against the role of fecal transplantation in increasing muscle mass from myostatin KO pigs.

      The authors achieved their aims, and the results support their conclusions.

    1. Reviewer #2 (Public Review):

      This paper reports a novel measure of biological age derived from machine-learning analysis of retinal imaging data with chronological age as the criterion measure. The resulting algorithm is impressive. Not only can the retinal image data accurately predict chronological age in the training data and record changes over short time intervals, but it also proves accurate in independent test data and appears to contain information related to mortality risk. In addition, the authors report a GWAS of the new measure.

      I would like to see a bit more validation data in the UKB - how does EyeAge relate to (a) tests of visual acuity - e.g. does it explain aging-related differences? (b) measures of morbidity and disability - e.g. how is EyeAge Accel associated with at least some of the counts of chronic diseases, self-reported physical limitations, tests of physical performance, measures of fluid intelligence?

      But overall, this is a very strong report of an exciting new biomarker of aging. It was unclear to me whether the algorithm to compute the measure would be publicly available. The authors should clarify.

    1. Reviewer #2 (Public Review):

      The paper by Ben Yaakov et al. describe a single cell analysis of the mammalian ovary in young, adult and old mice. In comparison with previous studies that used single cell RNAseq to characterize the heterogeneity of cell types in the ovary, this study focuses only on immune cells resulting in much better coverage to characterize the changes that these cells undergo as a function of age. The paper provides a useful dataset and informative data analysis with interesting findings including the increases in DNT cells in the ovary of old mice. Some discussion on how the presented results might be related to reduced fertility with age would be good to tie the results back to the original questions with which the authors start their paper.

    1. Reviewer #2 (Public Review):

      Zivanov et al. present a new approach for multi-particle averaging from cryo-electron tomography data. They propose that refining directly against 2D tilt series images instead of the traditional reconstructed 3D subtomograms would simplify and improve structure determination. This would represent the experimental data more faithfully than traditional subtomogram averaging and circumvents the need for missing wedge correction. The authors describe a data structure termed 'pseudosubtomograms' where the tilt images are represented as their Fourier transform pre-multiplied with the CTF, accompanied by an array describing how often each 3D-voxel has been observed and the sum of the squared CTF. They then present a new regularized likelihood target function for cryo-ET particle alignment which uses the pseudosubtomograms data structure. This approach is implemented within the general RELION refinement framework and allows for the use of pseudosubtomograms for 3D classification, initial model generation, and 3D refinement.

      The authors also introduce methods for refining optical and geometrical parameters in the tilt series taking advantage of the average map obtained after 3D refinement. This allows for more accurate tilt series alignment, per-particle motion tracking, and calculation of per-particle CTF. They propose that iteratively refining these parameters, extracting new pseudosubtomograms, and realigning the particles should lead to more accurate structure determination. The methods are validated using three different datasets, and the authors show that the iterative refinement within their framework increases the resolution of the 3D reconstruction and that the resulting maps are resolved to the same or better resolution than previously published methods.

      The introduction of a more direct representation of the 2D tilt series images is a novel approach to subtomogram averaging, and the authors show that it is as good or better than current approaches. Comparing the subtomogram average to the tilt series to correct for optical and geometrical parameters of the data has already been implemented in the program M. Here, the authors show that their algorithms can reach the same resolution as M for the HIV immature capsid, but discuss that M might be superior at very high resolution, as it models beam-induced rotation of particles. Nevertheless, the new approaches are implemented in a single framework - the popular open-source software package RELION - thereby greatly facilitating their accessibility to uses. This is a very welcome contribution and development in the field.

    1. Reviewer #2 (Public Review):

      In this manuscript, Ilmonen H. et al explored potential crosstalk between endothelial cells and fibroblasts in a context of sporadic vascular malformation (venous malformation and angiomatoses of soft tissue). With a high level of evidence, they found that mutated endothelial cells secrete TGFA that will activate surrounding fibroblasts, leading in turn to VEGFA secretion that will stimulate endothelial cell sprouting and vascular malformation development.

      Experiments are well-designed and support their hypothesis.

      Some controls are missing, particularly in Fig. 2. Indeed, it is mandatory to provide data from healthy skin biopsies (that are available in many laboratories): TGFa, CD31, P-EGFR staining.

    1. Reviewer #2 (Public Review):

      This study set out to explore the nature of a previously described non-competitive and selective inhibitor of the human glutamate transporter, EAAT1 and to explore if this mechanism was conserved across the glutamate transporter family. The non-competitive nature of UCHPH-101 inhibition of EAAT1 has previously been demonstrated with both functional analysis and structures of EAAT1. Here, the authors use detailed electrophysiology analysis to confirm this mechanism of inhibition and to demonstrate that the inhibitor slows the steps of the transport cycle associated with substrate translocation, rather than substrate or sodium ion binding. These findings agree with previous studies that have shown that the compound binds at the interface of the transport and scaffold domains in EAAT1, two domains that are required to move relative to each other for the transport process to occur. UCPH-101 also prevents the transporter from entering an anion-conducting state, which agrees with a recent structure and MD simulations of EAAT1 that demonstrate movements of the transport domain relative to the scaffold domain are required for the EAAT1 to move into the anion-conducting state and support the mechanism of UCPH-101 inhibition confirmed in this study (PMID: 35192345; PMID: 33597752).

      While UCPH-101 has been shown to be selective for EAAT1 over other human glutamate transporter subtypes (notably EAAT2 and EAAT3), Dong et al., show that this inhibitor can also reduce transport by another member of the SLC1A family, a neutral amino acid exchanger, ASCT2. Using MD simulations and functional analysis, they show that UCPH-101 acts as a partial, low-affinity inhibitor of ASCT2 and identify two amino acid residues in the binding site that appear to be responsible for the different affinities for EAAT1 and ASCT2. Indeed, when these two residues are changed to the corresponding residues in EAAT1, UCPH-101 becomes a full inhibitor of ASCT2 with an increased affinity.

      ASCT2 is a neutral amino acid transporter that can transport glutamine and it is known to be upregulated in several cancers. Thus, finding new compounds and novel ways to inhibit ASCT2 is worthy of investigation. In the last section of this study, the authors conduct a virtual screen of 3.8 million compounds to identify other compounds that could bind to this allosteric site in ASCT2. One compound was identified, and while it had relative low affinity it provides the basis for further exploration of this site.

    1. Reviewer #2 (Public Review):

      In this work, the authors aim "to assess whether the relationship between neural activity and hemodynamic responses is present" "before the time of normal birth". In other words, they aim at showing that neurovascular coupling is present before term-equivalent gestational age. They use simultaneous EEG and fMRI in preterm infants presented with tactile stimuli.

      Neuroimaging methods and stimulation methods are sound and rely on previously published works from the same group using neonatal MRI during somatosensory stimulation. The novelty resides in the use of simultaneous EEG to measure neuronal activity simultaneously with BOLD.

      Methodological weaknesses are related to:

      - Participant selection and characterization: there is a large variability in gestational age at birth, from very preterm (29 weeks) to late preterm (35 weeks) infants, which produces a large variability in chronological age at measurement (2 to 26 days). Considering how physiology and brain structure change dramatically with these factors, such variability seems an important bias. As stated in the introduction "In the time leading up to full-term human birth, rapid maturational changes are taking place across nearly all of the components which both relate to and occur within the neurovascular coupling cascade". There may be an effective neurovascular coupling in a neonate born at 35 weeks and tested at 2 days, and a very atypical or ineffective neurovascular coupling in an infant born at 29 weeks and tested after a month of intensive care, invasive respiratory support, and medication. This bias is also present in EEG analysis since "microstate basis vectors were derived from periods within the grand average signal that were topographically consistent across trials/subjects": any variability due to prematurity/NICU time is lost with this process.

      - Not accounting for sleep states. During sleep, preterm infants alternate between slow and agitated sleep states, the pattern of state cycles changing with gestational age. Although the authors used EEG, they do not report looking for sleep states. Sleep state changes during stimulation would likely affect strongly EEG microstates sequence, duration, and power, as well as BOLD amplitude and distribution (ipsi vs. contralateral). This would be easy to verify and would allow a deeper understanding of the data, such as the variability of EEG and BOLD responses in each participant and among participants.

      The main issue with the manuscript is the discrepancy between the stated aims ("to assess whether the relationship between neural activity and hemodynamic responses is present") and the literature available on the topic, on one hand, and between the stated aims and the actual work that was performed and discussed in the manuscript, on the other hand.

      Aims vs. literature: The presence of a neurovascular coupling before term-equivalent gestational age has already been shown years ago, including by this group. For example, in: Arichi, T., et al. (2010). Somatosensory cortical activation identified by functional MRI in preterm and term infants. NeuroImage, 49(3), 2063-2071, where the following sentence begins the Conclusion "This is the first description of well-localised somatosensory cortical activation in the premature brain using a fully automated and programmable passive motor stimulus. Predominately positive BOLD signal change during stimulation was seen".

      Or in:

      Arichi, T., et al. (2012). Development of BOLD signal hemodynamic responses in the human brain. NeuroImage, 63, 663-673.

      And by other groups using fMRI:

      Heep, A., Scheef, L., Jankowski, J., Born, M., Zimmermann, N., Sival, D., et al. (2009). Functional magnetic resonance imaging of the sensorimotor system in preterm infants. Pediatrics, 123(1), 294-300.

      Other examples of neurovascular coupling before term can be found with auditory-evoked BOLD responses in fetuses:

      Jardri, R., et al. (2008). Fetal cortical activation to sound at 33 weeks of gestation: a functional MRI study. NeuroImage, 42(1), 10-18.<br /> but also, with various types of stimuli using fNIRS, for example:<br /> Mahmoudzadeh, M., et al. (2013). Syllabic discrimination in premature human infants prior to complete formation of cortical layers. Proceedings of the National Academy of Sciences, 110(12), 4846-4851.<br /> And:<br /> Roche-Labarbe, N., et al. (2014). Somatosensory evoked changes in cerebral oxygen consumption measured non-invasively in premature neonates. NeuroImage, 85, 1-8.<br /> Including simultaneous EEG and fNIRS :<br /> Roche-Labarbe, N. et al., 2007. Coupled oxygenation oscillation measured by NIRS and intermittent cerebral activation on EEG in premature infants. NeuroImage, 36(3), pp.718-727.

      Be it in the Introduction or the Discussion, the authors only consider MRI literature whereas neurovascular coupling has been described and used for cognitive studies in premature neonates using fNIRS. There is no reason to restrict oneself to one technology when discussing fundamental physiological or cognitive processes.

      Aims vs. actual work: The work that was actually performed is to measure EEG microstates' duration and power following tactile stimulation and to compare BOLD amplitude with these measures. The question being answered is whether the relationship that exists between microstates duration and BOLD amplitude in adults can also be observed in preterm infants. This in itself is an interesting purpose and should be stated as such in the Abstract and Introduction.

      The Introduction is short and lacking in essential information. A review of microstates, what they are and what they mean, and how they are described in premature infants (particularly sensory-evoked microstates), is necessary. Previous studies of neurovascular coupling in preterm infants using evoked potentials, or no EEG at all when measuring the hemodynamic (fMRI or fNIRS) response associated with sensory stimuli. The introduction should argue why microstates would be more meaningful than SEP for EEG-fMRI studies, and what relationship with hemodynamics is expected based on previous studies with older participants. A comprehensive review of neurovascular coupling in preterm neonates, including non-MRI studies, is also necessary. The sentence "Here we test the hypothesis that despite the apparent immaturity of the underlying physiology, neurovascular coupling is functional before the normal time of birth." should be replaced by something along the lines of "Here we test whether the relationship between EEG microstates and neurovascular response is similar in premature infants with adults". Then the experimental contribution will make sense and the Discussion can focus on what it entails for understanding neurovascular coupling that amplitude is related to the duration, not power, of EEG microstates.

      A Discussion (distinct from the Results) of the scientific and clinical relevance is currently lacking and it is difficult to assess the significance of the experimental contribution. An interesting discussion of microstates in the preterm brain is presented, but because the topic of microstates' relevance in neonates was not mentioned in the Introduction, it is confusing to read results such as "the observed composite progression of microstates indicates that the preterm brain is already capable of multi-level local sensory elaboration in the primary sensorimotor cortices." that does not correspond to any previously formulated hypothesis.

      In the results, the authors should report if microstate duration varies among repeated identical stimuli in each child. The authors may look at this variability in terms of gestational age at birth (for example, in the participants who were born the earliest and have stayed the longest in the NICU, are microstates durations after a stimulus more variable than in the late-preterm participants?). The method for microstate analysis does not give clear information to the reader unfamiliar with Ragu other than the fact that one duration value was calculated for each participant. However, it would be informative to see some sort of dispersion range for both Mean BOLD and microstate duration values. It would be interesting to regress this information with gestational age at birth (or chronological age at scan) and sleep state.

      After these changes have been made, I expect that the authors may find a more relevant title for their manuscript. "Neurophysiological basis of hemodynamic responses" does not give a precise idea of the experimental findings. Similarly, the abstract should be adjusted by removing sentences like "These results suggest that effective neurovascular coupling is present in the human brain even before the normal time of birth", a long-known fact, and detailing instead "a complex relationship between EEG and fMRI signals underpinned by patterns of activity across distinct neural ensembles."

      Details of the stimulation sequence are unclear:

      - Why were stimuli varying in duration from 7.5 to 10.5 seconds? The results report "the median BOLD hemodynamic response peaked at 14 seconds after stimulus onset": was it calculated regardless of stimulus duration? It is unlikely that the peak was reached after the same delay for 7 and 10 s stim. Was this accounted for in the MRI analysis?<br /> - There was a maximum of 24 epochs per participant, but how many epochs were kept for each participant after artifact rejection? How were distributed the 76 epochs remaining for analysis, among the participants?

    1. Reviewer #2 (Public Review):

      The manuscript by Shepard et al. expands on prior recent publications by the group which demonstrated that silencing long ascending propriospinal neurons (LAPNs) disrupts left-right coordination in certain contexts in uninjured rats but improves locomotion following thoracic contusion. Here, the same reversible silencing strategy is used but instead targeted to the long descending propriospinal neurons (LDPNs). Interlimb coordination and several other locomotor metrics are examined in both uninjured and SCI conditions. The effects of LDPN silencing were quite similar to those of LAPN silencing with a few notable differences. In intact rats, the deficits were observed following silencing on both high and low-friction surfaces. The effects are stronger during the second Dox administration than during the first in intact, and possibly the opposite after SCI. Also, the reversal of deficits by silencing after SCI was more modest.

      The major strengths of the study are the methodology and research design employed. The reversible silencing of a specific population of neurons identified by the locations of their somata and terminals is powerful. This also allowed for comparisons of pre-/post-silencing in the same subject both in uninjured and SCI conditions. The primary shortcoming of the study is the lack of histological analysis to demonstrate the degree of loss and/or whether there is any selectivity or bias towards functional subclasses of neurons that are shown to be LDPNs, even at the level of ipsilateral/contralateral and transmitter phenotype.

      The presented data support the major conclusions of the study. It is interesting that silencing the LDPNs or the LAPNs, disrupting communication in either direction, has similar effects and that these effects are predominantly related to cross-cord coordination at each girdle. Additionally, the long propriospinal neurons, LDPNs in particular, are thought to be potential targets for relays and adaptive plasticity after spinal cord injury. However, their silencing after SCI leads to locomotor improvements rather than exacerbated of dysfunction. Whether this is due to an imbalance of spared projection neurons, maladaptive plasticity/sprouting, or other mechanism is of interest for future studies targeting spared projections to enhance functional recovery.

    1. Reviewer #2 (Public Review):

      The manuscript by Zeng and colleagues aims to investigate how neural representations of sensory cues in two modalities (visual and vestibular) change when conflicts are introduced between the cues. The manuscript convincingly demonstrates that this recalibration process differs between areas MSTd (a multisensory region), where sensory responses recalibrated differently for visual and vestibular cues, following each modality's conflict, and area VIP ( a higher-level region), where responses follow the vestibular cue. More limited insights are present for area PIVC, where visual responses are limited.

      The analyses generally support the conclusions of the authors, but I have two major suggestions to strengthen the statistical robustness of the manuscript:

      1) The analysis about the lack of visual recalibration in area PIVC would have been more convincing if the authors had used Bayesian statistics instead of regular t tests. In this way it would have been possible to estimate if the lack of visual recalibration in this area, for those few neurons that show visual tuning, can be taken as evidence for the absence of an effect or not. In the absence of this additional analysis, it is in fact difficult to properly interpret the results about area PIVC. Is PIVC more in line with MSTd, in view of the lack of visual responses? Or is there actually no visual recalibration, in contrast to both MSTd and VIP?

      2) For all statistical analyses, multi-level statistics would have been more appropriate than simple t-tests. In fact, since recordings come from few subjects, which in turn have relatively few recording sessions, there is a risk that the results are influenced by one subject and do not represent the full population. Admittedly, this is unlikely in view of the apparently large effect size and low p values. Nonetheless, a more appropriate statistical analysis would make the results more robust and convincing.

      Once these issues are addressed, I believe that the manuscript would provide relevant evidence supporting the hypothesis that multisensory processing in the cortex is an area-specific phenomenon, and that effects observed in one area cannot be simply expected to operate elsewhere. This will therefore elucidate the mechanisms of multimodal plasticity.

    1. Reviewer #2 (Public Review):

      Previous work from the Brown lab showed that SM undergoes proteasomal dependent processing of its N-terminal regulatory region to generate truncSM, which retains catalytic activity. In this manuscript, Hudson and colleagues show that the generation of truncSM correlates with hypoxic conditions. This process appears to be independent of the transcription factor HIF1α and proline hydroxylation. Instead, their data suggest that hypoxia-induced truncSm results from 1) upregulation of the E3 Ub ligase MARCH; 2) accumulation of squalene, the substrate for SM. Finally, the authors have linked these observations to pathologies, such as hypoxic endometrial cancer tissues, arguing that overactive truncSM may contribute to the growth and survival of malignant cells. Overall, this paper provides some interesting concepts on the regulation of the cholesterol biosynthesis pathway upon low oxygen levels. However, the functional consequences of truncSM accumulation under hypoxia have not been addressed.

      Another important open question is the role of squalene in promoting truncSM. Any additional information to address these issues would significantly strengthen this study. The analysis and some of the data on the relative abundance of SM and truncSM could also be improved.

  2. Nov 2022
    1. Mais de 1.000 escritórios estão crescendo com a Hero

      Vale trazer mais Big Numbers aqui e, inclusive, abrir espaço para o "100 Startups to Watch" e "Selo do Reclameaqui"

    1. Reviewer #2 (Public Review):

      This study investigates how thalamic functional MRI activations change across subjects performing many cognitive tasks. The results reveal localised regions in anterior, medial (and potentially posterior) portions of the thalamus that co-activate most consistently across multiple tasks. The authors then try to link these task hubs to cortical association cortices, first by showing that association cortices are most connected to thalamic task hubs. Second, by showing that thalamic activations can predict

      The findings are important, mainly because thalamic fMRI activations are largely ignored by the current literature. The major strengths of the study lie in examining thalamic activations under many cognitive tasks and replicating results across two independent datasets.

      The findings of thalamic hubs are compelling. However, this current version of the manuscript could be strengthened by providing better links with the wider literature (e.g. with thalamic resting-state networks). The study also falls short in properly quantifying the similarity of findings across the two independent datasets. The subtle discrepancies between the results of the two datasets throughout the manuscript could point to finer-grained fractionations of the identified thalamic hubs. The least compelling set of results (though not necessarily wrong) is the thalamic prediction of cortical activations. This is because the functional connectivity (FC) matrix used to link the thalamus and cortex was derived from the same data after regressing out task-related variance. However, this process might not be clean enough. A stronger test would utilize an FC matrix derived from an independent dataset.

    1. Reviewer #2 (Public Review):

      One major enigma in neurodegeneration is why it tends to start many times in the entorhinal cortex. This paper tries to address this issue, by showing the vulnerability of reelin-positive entorhinal cells to inactivation, thus leading to the compelling idea that neurodegenerative processes are initiated by prolonged brain inactivity in specific brain regions. The paper is straightforward and performs a whole set of experiments to demonstrate the specificity of the effect on these cells, trying to partially decipher the underlying mechanisms which lead to the vulnerability of these specific cells.

      The paper performs a series of tests on these cells. First, the chemogenetic silencing of layer 2 entorhinal neurons causes cell death and axonal degeneration. Second, this effect is specific to entorhinal neurons and spares other regions. Third, the effect seems to be mediated by synaptic silencing, in addition to general neuronal inactivity, and finally - the effect seems to be governed by neuronal competition and not by a general non-specific change in neuronal activity levels.

      I think the paper is a great first step. In the future, more work will be needed in order to better understand the causes of this vulnerability and to connect this work to the cascade of neurodegeneration leading to the known phenomena associated with AD.

    1. Reviewer #2 (Public Review):

      In this study, the authors determine the superior cell killing abilities of KLRK1+ IL7R+ (KILR) CD8+ effector T cells in experimental diabetes and tumor mouse model. They also provide evidence that Tregs suppress the formation of this previously uncharacterized subset of CD8+ effector T cells by limiting IL-2.

      Strength and Limitation

      This study focuses on the relationship between Tregs and CD8+ T cells. They used different experimental diabetes mouse models to reveal that Tregs suppress the CD8+ effector T cells by limiting IL-2. They also found a unique subset of KLRK1+ IL7R+ (KILR) CD8+ effector T cells with superior cell killing abilities through single-cell sequencing, but killing abilities could be inhibited by Tregs. They also tested their theory in in vivo tumor model. The data, in general, support the conclusions; however, some issues need to be fully addressed, as detailed below.

      1. This study used the concentration of urine glucose as the standard for diabetes ({greater than or equal to} 1000 mg/dl for two consecutive days). However, multiple reasons may lead to a high level of urine glucose. As a type I diabetes mouse model, authors could use immunohistological analysis of islet to show the proportion of T cells and islet cells in islet, which can display the geographic distribution of immune cells, severity and histology structure of damaged pancreas islet directly. If possible, different subsets of immune cells, especially CD4 vs CD8+ cells should be stained for their location.

      2. This article shows that KILR effector CD8+ T cells have strong cytotoxic properties. However, they do not describe the potential proliferation ability vs apoptosis of this subset from islets.

      3. Figure 7 shows that the antitumor efficacy of IL-2 depends on CD8+ T cells. But in this part, there is no data to show the change of KLRK1+ IL7R+ CD8+ effector T cells in tumor tissue. Therefore, the article needs to add more data to verify that IL-2 enhances antitumor ability via KLRK1+ IL7R+ CD8+ effector T cells.

      4. It is unclear why the authors chose Dox to combine with IL-2/JES6. The authors should provide a more rational introduction to bridge such a combination. Authors should also explain the reason why there is no antitumor effect of IL-2/JES6 treatment alone.

    1. Reviewer #2 (Public Review):

      This paper provides a novel approach to quantifying the tradeoff between energetic optimality during walking and the valuation of time to travel a given distance. Specifically, the authors investigated the relationships between walking speed trajectories, distance traveled, and the valuation of (completion) time. Time has been proposed as a potential factor influencing movement speed, but less is understood about how individuals balance energetic optimality and time constraints during walking. The authors used a simple, sagittal-plane walking model to test competing hypotheses about how individuals optimize gait speed from gait initiation to gait termination. Their approach extends literature in the space by identifying optimal gaits for shorter, partially non-steady speed walking bouts.

      The authors successfully evaluated three competing walking objectives (constant acceleration, minimum cost of transport at steady speed, and the energy-time objective), showing that the energy-time objective best matched experimental data in able-bodied adults. Although other candidate objectives may exist, the paper's findings provide a likely-generalizable explanation of how able-bodied humans select movement strategies that encompass studies of steady-speed walking.

      Overall, this paper provides a foundation for future studies testing the validity of the energy-time hypothesis for human gait speed selection in able-bodied and patient populations. Extensions of this work to patient populations may explain differences in walking speed during clinical assessments and provide insight into how individual differences in time valuation impact performance on assessments. For example, understanding whether physical capacity or time valuation (or something comparable) better explains individual differences in walking speed may suggest distinct approaches for improving walking speed.

      Strengths:<br /> The authors presented a compelling rationale for the tradeoffs between energetic optimality and time and their results provide strong support for a majority of their conclusions. In particular, significant reductions in the variance of experimental speed trajectories provides good support for the scaling of speeds across individuals and the plausibility of the energy-time hypothesis. Comparison to theoretical (model-based) reductions across difference time valuation (cT) parameters would further enhance confidence in the practical significance of the variance reductions. Further, while additional work is needed to determine the range of "normal" valuations of time, the authors present experimental ranges that appear reasonable and are well explained. The computational and analytical methods are rigorous and are supported by the literature. Overall, the paper's conclusions are consistent with experimental and computational results.

      The introduction of a model-based analytical approach to quantify the effects of time valuation of walking could generalize to test other cost functions, populations, or locomotion modes. Further, models of varying complexity could be implemented to test more individualized estimates of metabolic cost, ranging from 3D dynamic walking models (Faraji et al., Scientific Reports, 2018) or physiologically-detailed models (Falisse et al., Journal of The Royal Society Interface. 2019). The relatively simple set of analyses used in this paper is consistent with prior literature and should generalize across applications and populations.

      The authors justified simplifications in the analysis and addressed major limitations of the paper, such as using a fixed step length in model predictions, using a 2D model, and basing energy estimates on the mechanical work of a simple model. It is unlikely that the paper's conclusions would change given additional model complexity. For example, a 3D walking model would need to control frontal plane stability. However, in able-bodied adults, valuation of frontal-plane stability during normal walking would not likely alter the overall shape of the predicted speed profiles.

      Weaknesses:<br /> The primary weakness of this work is that alternative objectives may provide similar speed profiles and thus be plausible objectives for human movement. For example, the authors tested an objective minimizing the steady-speed cost of transport. This cost function is consistent with the literature, but (as predicted) unlikely to explain acceleration and deceleration during gait. An objective more comparable to the energy-time hypothesis would be to minimize the net energy cost over the entire bout, including accelerations and decelerations. This may produce results similar to the energy-time hypothesis. However, a more complex model that incorporates non-mechanical costs (e.g., cost of body weight support) may be needed to test such objectives. Therefore, the energy-time hypothesis should be considered in the context of a simple model that may be incapable of testing certain alternative hypotheses.

      An experimental design involving an intervention to perturb the valuation of time would provide stronger support for time being a critical factor influencing gait speed trajectories. The authors noted this limitation as an area of future work.

      While the results are compelling, the limited sample size and description of participants limit the obvious generalizability of the results. Older adults tend to have higher metabolic costs of walking than younger adults, which may alter the predicted time-energy relationships (Mian OS, et al., Acta physiologica. 2006). As noted in the introduction, differences in walking speeds have been observed in different living environments. General information on where participants lived (city, small town, etc...) may provide readers with insight into the generalizability of the paper's conclusions. Additionally, the experimental results figures show group-level trends, but individual-specific trends and the existence of exceptional cases are unclear.

      The authors' interpretation of clinical utility is vague and should be interpreted with caution. A simple pendulum-based walking model is unlikely to generalize to patient populations, whose gait energetics may involve greater positive and negative mechanical work (Farris et al., 2015; Holt et al., 2000). Additionally, the proposed analytical framework based on mechanical work as a proxy for the metabolic cost may not generalize to patient populations who have heterogeneous musculotendon properties and increased co-contraction (e.g., children with cerebral palsy; Ries et al., 2018). Consequently, the valuation of time for an individual could be incorrectly estimated if the estimates of metabolic cost were inaccurate. Therefore, as the authors noted for their able-bodied participants, more precise measures of metabolic rates will be critical for translating this work into clinical settings.

    1. Reviewer #2 (Public Review):

      This paper by Tomanek and Guet investigates the evolutionary dynamics of the very earliest steps in the process of evolution through gene duplication and divergence. They use a cleverly designed experimental system where they can tune the benefit of mutations that cause increased expression of a gene, and where they have reporter genes that can be used to distinguish between promoter up mutations and (most) gene duplications.

      The major conclusion is that the dynamics of adaptive gene duplications and adaptive point mutations can be very different in different conditions - In "low demand" conditions, where a single mutation (duplication or snp) is enough to achieve the maximum (for that environment) fitness improvement duplications and promoter mutations acts with negative epistasis and become mutually exclusive. Contrary to previous literature that discusses evolution by duplication - divergence, duplications can thus act to prevent or slow down divergence.

      The strengths of the paper: The genetic system is simple but cleverly designed. Using a gene (galK) that made it possible to tune the benefit of increased expression (by varying the amounts of galactose in the growth medium) made it possible to make observations that others have missed.

      Possible weakness, which this paper has in common with much of the literature on evolution by duplication-divergence: Duplications are very often very unstable and are lost at rates that exceed their rate of formation. This means that in the absence of selection duplications are usually lost very quickly unless selected for, and all experiments and conclusions are based on stable conditions with a continuous selection that may not reflect a natural situation.

      The aims of the paper were achieved and the presented data support the conclusions nicely.

      This paper provides evidence that evolution by gene duplication is more complex than how it is usually described. Even if two mutations (e.g. gene duplication and promoter mutations) have additive or positive epistasis on a measurable quantity (be it enzyme kinetics, gene expression levels, or some other observable trait) the mutations could show negative (or even sign?) epistasis on the fitness of an organism. Hopefully, this paper will serve as a reminder of this even outside of the duplication-divergence field.

    1. Reviewer #2 (Public Review):

      C-type lectin receptors are well-known for their pathogen recognition and their immunoregulatory properties. However, most C-type lectins also engage host-derived ligands. While many microbial targets have been identified, the characterization of endogenous ligands has so far lagged behind. In this paper, Haji et al. identified human Dectin-1 as a bonafide self-ligand for the platelet-specific C-type lectin receptor CLEC-2.

      Strengths:<br /> Haji et al. actually identified the first glycan-dependent C-type lectin - C-type lectin interaction, resulting in a 2-way activation cascade downstream of both the Dectin-1 and CLEC-2 receptors. They performed a highly detailed molecular characterization, revealing both the interacting domains with Dectin-1 as well as the interacting glycan sialylated core 1 ligand. Moreover, the authors provide proof of the functional relevance of the Dectin-1 - CLEC-2 interaction in a mouse model deficient for the CLEC-2 ligand podoplanin, demonstrating that human Dectin-1 can rescue the phenotype observed in these podoplanin KO mice.

      Limitations:<br /> The main limitation of this work is the use of Dectin-1 and CLEC-2 transfectants. Glycosylation patterns in transfected 2B4 cells (a T cell line) might not mimic the natural glycosylation pattern on Dectin-1 in vivo. A follow-up study should address which human Dectin-1 positive immune cell subsets are recognized by human CLEC-2 and how human Dectin-1 glycosylation is regulated during immune cell activation and differentiation.<br /> In addition, Dectin-1 polymorphisms have been identified in the human population, which strongly decreases Dectin-1 expression. Yet, these individuals mainly suffer from fungal infections and so far have not been shown to have lymphatic defects. This leaves the actual in vivo role of the human Dectin-1 - CLEC-2 interaction yet to be resolved.

    1. Reviewer #2 (Public Review):

      Because individuals in most colonies of eusocial insects (i.e., ants, social bees, social wasps, and termites) cannot directly reproduce, theory suggests that natural selection will shape the behavior and physiology of such individuals to be hyper-sensitive to the needs of their colony. In the context of foraging, an individual should make decisions of how often to search for new food based on the "hunger" of the colony that she belongs to. In fact, in previously published work, the authors of this manuscript have confirmed empirically that the frequency of foraging events for individual workers in colonies of _Camponotus sanctus_ carpenter ants is correlated with the amount of food stored within the collection of ants within the nest -- as the colony "satiated" (i.e., the communal stomach of the average nest ant became full), the foraging frequency would decrease (and vice versa). In that work, the authors showed that an individual's decision to leave a nest to return to foraging was predictable from her own communal stomach ("crop") level and how quickly it was being depleted by nest ants receiving it. From that observation, the authors previously suggested that a cognitive process within each individual ant could monitor these two internal variables (crop level and rate of change) and lead an ant to make a decision as to if and when to leave a nest. In the current work, the authors suggest an alternative mechanism that exports the discrete decision making into the nest cavity itself and only requires an individual forager to adjust her movement pattern based on her current level of crop load. In particular, they use computational and mathematical models to show that spatiotemporal statistics similar to real ants emerge when hypothetical modeled foragers move deeper into a nest when their crop level is above a certain threshold and instead move toward the nest exit when their crop level is below that threshold (leaving the nest when randomly encountering it). This simple crop-based rule does not require estimation of depletion rate nor require an ant to deliberate over when to exit. Foragers in "hungry" colonies have shallow penetration in their nests before turning around and quickly returning to foraging while foragers in "satiated" colonies have deeper penetration and may remain in their nests for long periods of time. This proposed mechanism provides the adaptive foraging patterns observed in real carpenter ants with significantly reduced assumptions about individual cognitive abilities when compared to previous mechanistic explanations of this behavior. Broadly speaking, it (combined with other recent work from these authors and others) helps to demonstrate proof of concept of cognitive hypotheses that are embodied in the physical environment around the individual apparently making the decision.

      The movement rule proposed by the authors is elegantly simple and produces trajectories that are, at least to the human eye, a good match to the stereotyped trajectories from real ant colonies in terms of their directionality and duration, and the length of these trajectories is modulated by colony hunger-state in exactly the same way as the real ant trajectories. Although the authors do not provide statistics on multiple runs of the simulation (they provide examples of single runs), they do complement their simulation work with both deterministic and stochastic models of statistics of the modeled paths and show that those statistics have the same qualitative relationship to colony hunger-state as the statistics of the real ants. Consequently, the paper provides a compelling argument via the use of multiple types of models for a novel behavioral rule that answers an important question in collective decision making in confined physical spaces.

      Much of the authors' argument rests on trajectories and statistics generated from a two-dimensional computational simulation that may be overly simplistic. The computational model simulates a single forager (as opposed to multiple foragers) arriving to a nest that is partitioned into a grid of squares with an immobile ant in the center of every square. Foragers move in discrete steps from square to square, with the guarantee of an interaction in each step. This "grid world" model of ant nest movement is significantly different than the experience of real foraging ants returning to the nest, and the authors even admit that deviations between the empirical data and the computational model may be due to nest-ant clumping and interaction sparsity in the paths of real ants. Continuous-motion agent-based models are commonly used to investigate collective-motion hypotheses, and so the choice of a grid world model instead seems notable and weakens the authors' arguments. Furthermore, whereas the deterministic mathematical model of grid-world forager trajectories seems too simplistic, the stochastic model buried in the appendix that is meant to validate the deterministic model's results seems to have some potential flaws and is itself not validated experimentally against replicated simulation data. Instead of perfecting these models, the authors could have bolstered their arguments using more familiar approaches from statistical mechanics that might help explain the likely depth an ant "diffuses" into such a nest. In the current form of the manuscript, the mathematical models do not add much beyond the simulation models (and the lack of replication of the simulated data may make some readers wonder if the example trajectories are representative).

      There are also a few questionable parameters that the authors have chosen in their model, likely for analytical tractability. For example, the authors assume that at each interaction between a forager and a nest ant, the forager offloads enough food to fill 15% of the crop space remaining in the receiving ant. One can assume that this parameter is something like the 63.21% associated with an exponential time constant or may be based on empirical measurements of transfer in real ants, but the actual justification is not completely clear from the manuscript. Because the mathematical models make predictions that depend upon these parameters, their existence (and plausible values) is itself an important assumption that needs to be defended for the argument to be truly compelling.

      Beyond these methodological issues, the behavioral model described by the authors assumes that ants are able to choose a direction toward their nest's entrance at any time. This within-nest path-integration ability does not seem cognitively inexpensive, which narrows the cognitive distance between the behavioral model they propose here and the one they proposed in their prior work and weakens the argument for the relevance of this new model. The authors failed to place their work within the context of other simple cue-based motion-switching behaviors discussed in the literature for other taxa - such as "running" and "tumbling" in E. coli bacteria - but if they had, they might have envisioned an alternative crop-based motion rule that would have the same effect as their current rule (i.e., movement toward the entrance on low crop state) without having to assert that the ant moves directly back toward the entrance.

      Focusing on the explanatory power of this model specifically for (some) ants, the authors do not address how to empirically reconcile the ambiguity between the more cognitive mechanisms proposed in their previous work (where ants "decide" to exit a nest) and the current proposal (where the nest cavity "decides" when the ant will exit). For this new hypothesis to be useful, it must be empirically discriminable from the previous hypothesis. At first glance, it is difficult to imagine an experiment that would lead to different predicted behavior from the two different hypotheses. In other words, at the moment, it seems impossible to tell whether the "ant decide" or the "nest decide" model is a better predictor of real ant behavior/cognitive architectures. The lack of discriminability becomes even more problematic when considering that the current version of the model actually increases some cognitive demands by assuming (as described above) that ants keep track of the position of the entrance over the trajectory within the nest.

      The arguments in the current form of this manuscript could be strengthened by adding realism, connections to related literature in collective motion and motion ecology, and more general models from statistical mechanics, and it is important for the authors to identify potential ways to empirically discriminate between the model introduced here and the behavioral model suggested in their prior work. That said, the salient features of the basic crop-cue-based two-motion-primitive model proposed by the authors are elegant and novel and help to further demonstrate how cognition can be embodied in the physical spaces it is embedded within. The authors focus on a particular example in ants, but it is easy to imagine extending the same model to a variety of other scales and application spaces. For example, there may be microbiological examples of coordination among collectives where individuals face even more stringent cognitive constraints. Moreover, the same methods might be used to build artificial swarms in engineering contexts that allocate to tasks based on demand without significant communication or sensing requirements. Even in industrial organization, there may be ways to use methods like these to ensure an emergent adaptive re-allocation of human workers to tasks based on need. In general, this manuscript provides a new example of how spatiotemporal properties of decision making long thought to be associated with cognitive processes endogenous to individuals can be alternatively generated by simple cue-based behaviors interacting in a non-trivial environment. This is a relatively new perspective that may be useful in both the analysis of natural systems as well as the design of artificially intelligent systems. With the right framing, the example from this manuscript could be very useful not only to ant biologists but to scientists and engineers interested in collective decision making more broadly.

    1. Reviewer #2 (Public Review):

      The authors' paper extends their earlier work based on a 2D model of running stability while negotiating sloped terrain of random variable height, extending from a traditional point mass-spring model (SLIP) but with a moment of inertia about the CoM ([19], Dhawale et al. Roy Soc Open Sci 2019). In this study the authors carry out an experimental study of human subjects running over an experimentally-created undulating terrain surface (0.6 m wide x 24 m long) with a known 3D topography, in which they combine a 3D kinematics analysis of foot movement trajectory and placement relative to the terrain topography and in relation to body CoM (hip) movement; with measurements of ground reaction forces to estimate foot-substrate impulses over a subregion of the terrain, and measurements of the runners' metabolic energetics via a portable runner-carried gas analyzer system.

      The authors' findings are generally supported by their results, showing that runners do not appear to rely on visual guidance to select foot placement on undulating terrain (this based on computational Monte Carlo simulations of foot placement probabilities favoring level terrain surfaces) and likely achieve stability while running largely by means of limb joint compliance that passively adjusts to variable foot-ground impulses (based on ground reaction force estimates and a collisional multi-segment limb joint model for which joint compliance was varied). As a result, the authors found no significant increase in the metabolic cost of uneven terrain versus level surface running.

      However, whereas the authors motivate their study by its relevance to the evolution of human running ability and persistence hunting, which requires running over uneven natural terrain, a weakness is that their in-depth analysis is heavily focused on the mechanics and resulting energetics of running over undulating terrain in the context of foot placement strategies for maintaining stability and whether this depends on visual guidance of foot placement relative to the terrain. The authors claim surprise (Discussion, l.191-192) that the runners do not appear to rely on visual information about unevenness to guide their footsteps. However, based on the nature of their sloped undulating surface, their results were unsurprising to this reviewer.

      The authors' study was also motivated to examine the effect of sloped surfaces on running biomechanics, as previous studies have examined step-like terrain comprised if piecewise level blocks or step height transitions, which the authors (correctly) note represent obstacle negotiation rather than how runners may be challenged by undulating sloping terrain. The authors argue (l. 5-6) that a combination of height and slope variations like a natural undulating terrain will be more challenging than one that involves only step height transitions. However, the basis for this statement is not clear. And, indeed, the results the authors find for humans running over a sloped, undulating terrain (height range ~ 40 mm) shows that a sloped, undulating terrain does not actually present a significant challenge, given that it appears to require little or no visual guidance of foot placement and no significant increase in metabolic energy use. To the contrary, this reviewer would argue that obstacle avoidance is the more challenging feature of natural terrains that must be successfully negotiated, which is a common experience for trail runners. The reviewer, therefore, fully agrees with the authors' conclusion (l. 259-261) "Our data thus suggests that terrain-guided foot placement strategies are not required for stability on gently undulating terrain [compared with obstacle avoidance on more complex terrain]".

      The principal novelty and value of the authors' study is the analysis of fore-aft impulse and the role of limb joint compliance for adjusting to changes in fore-aft impulse to favor running stability. The authors' paper suffers from overstating the broader relevance of its findings and by merging methods and discussion with the results that it reports. The methods, themselves, are detailed and thorough in their description, and the authors' modeling approaches appear sound, sophisticated and appropriate for the analyses of foot placement strategies and limb compliance in relation to collisional impulse.

      Repeatedly in the Results section, however, these methods are summarized when reporting a result (based on the method) and discussion points are mentioned. Specifically:

      l. 66-96 This starting section does not present results per se, but a summary description of experimental methods an analytical approach. Actual results findings are not presented until l. 97.

      l. 111-117: This summarizes analytical methods; not results per se.

      l. 135-145: Summary of methods/analytical approach continues to be blended in with results in these sections.

      l. 169 - Comparison of limb retraction rate on uneven vs level terrain of human subjects here with running birds is fine for discussion but not results per se.

      l. 170-171: This is a discussion point, not a result.

      l. 187-189: Again, discussion not a result.

      A final concern is whether and how the requirement that runners repeatedly decelerate, turn and reaccelerate to run back and forth over the 24 m long uneven and level terrains at 3 m/s affects the metabolic measurements? Running at 3 m/s indicates 8 sec to traverse the runway length and, if adding another second for turning to reverse direction and run back = 9 s, this would indicate for a 8 to 10 min metabolic running trial ~53 to 67 turns per trial. Presumably, these would have an effect on running cost.

    1. Reviewer #2 (Public Review):

      Vries et al. investigated the mechanism of the color categorical perception and tried to answer the question of whether it develops universally or it is relative to local communication. So they investigated whether a categorical representation of color emerges from a Convolution Neural Network (CNN) that is trained to perform an object recognition task. The results indicate that the CNN has a categorical representation of color, which suggests that the color categorical perception might emerge from the object recognition.

      In general, I think the results are interesting. They performed a psychophysical experiment with the CNN, which shows the border of color category was largely invariant to the training colors. Also, further experiments with the evolution algorithm and other experiments confirm this.

      However, I think the approaches to address this question are not straightforward. All of the approaches in the paper rely on the retraining of the last layer. I was hoping they would provide more direct evidence to support their claim. Also, if they can show the color categorical information revealed by the CNN is similar to the human's color perception, that would help to strengthen their claim.

    1. Reviewer #2 (Public Review):

      In this study, the authors collected and analyzed blood samples from >9,000 participants from two cross-sectional cohort studies in the UK. The ALSPAC cohort only collected data during April and May 2021, whereas the TwinsUK cohort collected data during April and May 2021 and November 2021 to January 2022. They measured anti-Nucleocapsid and anti-Spike antibodies using the collected blood samples. They investigated the variation in antibody levels and risk factors for lower antibody levels following each round of SARS-CoV-2 vaccination across a wide range of socio-demographic, SARS-CoV-2 infection and vaccination, and health factors. Alongside the descriptive analysis, the authors performed some multivariable regression analysis.

    1. Reviewer #2 (Public Review):

      Fuhrman et al. explore a fascinating system to study the evolution and genetic architecture of ecological adaptation in marine midges. They use a number of approaches including analyses of whole genome sequences and QTL mapping to explore population structure and the loci associated with the timing and mode of reproduction. I have some concerns about the analyses and interpretations which I outline below.

      1) My primary concern is in the design and interpretation of the QTL analysis. The QTL approach used here has low power, both due to the sample size and the number of markers used (it looks like ~8 per chromosome). The authors use an analysis of the sex determining locus as a "control" but because of the complete heritability of this trait in most systems it is more of a straw man to me. The authors conclude that the architecture of the trait is polygenic based on this, but we are missing key information to evaluate this.

      2) There are some issues with the presentation and interpretation of the population genetic analyses. Many assumptions are made about whether introgression or ILS occurred and there are statements that are not accurate about it being "impossible" to distinguish between these scenarios.

      3) Some of the analyses associated with ecological adaptation that follow on the QTL results struck me as ad hoc and with the potential to lead to spurious results. I am not familiar with the BayPass approach but since it is the approach that explicitly accounts for population structure it seems the one that would be most appropriate for the authors to focus on in a revised manuscript. The use of phylogenetic windows that associate with ecotype is concerning to me as given the level of ILS and gene flow that appears to be present in this system is would be very challenging to distinguish signal from noise.

      4) There were issues with the GO analysis that should be addressed. Because the gene universe used for GO enrichment is a subset of the full gene set, GO enrichment results will be biased. This will mostly lead to false positives (i.e. overrepresentation of a GO category due to evaluating a subset of genes that fall in that category).

    1. Reviewer #2 (Public Review):

      In this manuscript the authors develop a method, SpecVar, to perform heritability estimation from regulatory networks derived from gene expression and chromatin accessibility data. They apply this approach to public datasets available in ENCODE and Roadmap Epigenomics consortia as well as GWAS phenotype associations in UK Biobank. It promises to be a powerful method to interpret mechanisms from genetic associations. Below are some strengths and weaknesses of the paper.


      - The method performs heritability enrichment on two major genomic data types: gene expression and chromatin accessibility.<br /> - This method leverages gene regulatory networks to perform the heritability estimation, which may better capture complex disease architecture.<br /> - The authors perform an extensive comparison to other LDSC-based approaches using different tissue datasets.

      Weaknesses<br /> - This approach may represent a modest advance over existing LDSC methods when looking at other complex traits.<br /> - The authors only compare with LDSC using different functional annotations as input, which may not be appropriate. A more broad comparison with other heritability methods would be helpful.<br /> - The method seems to be applied to "paired" data, but this is still bulk profiles not paired single-cell RNA/ATAC data.

      The authors successfully applied a regulatory network approach to improving the heritability estimation of complex traits by using both gene expression and chromatin accessibility data. While the results could be further strengthened by comparing them to other network and non-network-based methods, it provides important insight into a few traits beyond the standard LDSC model with different functional annotations.

      Given that this method is based on the widely used LDSC approach it should be broadly applied in the field. However, the authors should consider adapting this to single-cell data as well as admixed human population genetic data.

    1. Reviewer #2 (Public Review):

      The authors described the analysis of a magnesium transporter UEX as a sleep-regulating gene in Drosophila melanogaster. They also proposed the UEX regulates sleep through its downstream Ca2+-dependent CREB signaling and a CNK-dependent ERK pathway. The involvement of UEX in sleep regulation is novel and potentially interesting, but the data presented in the manuscript does not fully support the conclusions the authors proposed. Most of the data are derived from elav-GAL4, which is a non-specific pan-neuronal GAL4 driver. Since as the authors described, UEX functions to alter sleep in various brain regions, the relationship between UEX and other molecules in Ca2+-dependent CREB signaling and a CNK-dependent ERK pathway may be indirect in the sleep-regulating pathway, which means it may involve multiple regions of the brain using different pathways, and the sleep phenotype is the summation of different functions of UEX.

    1. Reviewer #2 (Public Review):

      Appropriate brains functions require the precise wiring of vast numbers of synaptic connections in broadly distributed neural circuits. Monosynaptic retrograde rabies virus tracing has become a common approach in neuroscience to assay presynaptic inputs into a given postsynaptic region. However, quantification and interpretation of rabies tracing data is confounded by the lack of uniform and appropriate measuring approaches across different studies and laboratories, as well as the lack of knowledge of the trans-synaptic transfer properties of different rabies viruses in various brain regions.

      The current study comprehensively applies mathematical approaches to an example rabies tracing dataset in layer 5 of mouse visual cortex, as well as previously published datasets, to propose more standardized methodologies for rabies data analysis and interpretation. The major strength of the study is the rigorous and unbiased mathematical approaches applied to their data and a range of previously published studies in the field. Inclusion of representative image data would be helpful for readers and would further strengthen the study. Given the ubiquitous use of rabies virus tracing in the field, yet lack of insight into this crucial aspect of its use, this will provide a useful resource for the neuroscience community.

    1. Reviewer #2 (Public Review):

      In most organisms, DNA replication is restricted to a relatively few cytologic structures termed replication factories. Studies indicate that such factories contain multiple replication forks. Although these observations suggest that replication fork colocalization has functional significance, the biological rationale for replication factories has remained elusive. To address this issue, the current study utilizes E. coli, a bacterium with a circular chromosome that replicates its DNA bidirectionally from a single origin of replication. During the first half of an E. coli DNA replication cycle, these two forks spatially co-localize into a single "factory." The experimental plan of this study is to block one of the two replication forks at various informative genomic locations and see if such blocks affect the progression and efficiency of the non-blocked fork. Using this approach, the authors find that blocking the progression of one fork at an early point in replication slows the progression of the corresponding unblocked fork and considerably increases its probability of replication fork collapse. This study considerably advances the field by demonstrating for the first time a possible biological purpose behind the replication factory - that factory formation in some yet unknown manner helps coordinate and stabilize bidirectionally oriented replication forks.

      Although others have tried to study replication factories using similar experimental logic, this well-written study by Chen et. al. examines the problem with higher sensitivity and resolution using a very elegant and synergistic approach that combines 3-dimensional microscopy, deep DNA sequencing, and old-fashion cell biology with a series of carefully engineered E. coli strains containing a conditional replication fork block in different informative genomic locations. These approaches in combination allow one to make a direct experimental correlation between cytologically defined replication factories (3D fluorescent imaging of labelled replication factors with image deconvolution), and fork progression via an analysis of copy number (genomics). Their experimental approach and accompanying analysis pipeline will be of general interest to the research community.

      In addition to a very careful analysis of factory formation that helps resolve several previous discrepancies on this subject, the authors used this approach to show that blocking one replication fork early in DNA replication coordinately decreases both the rate of fork progression and the level of fork stability in the unblocked sister fork. This conclusion is supported by their genomic analysis that shows the velocity of the unblocked fork slows when the other fork is blocked. To further elucidate this observation, the authors examined the likelihood that elevated replication fork collapse contributed to the decreased fork rate. As the restart of a collapsed replication fork depends upon genetic recombination, the role of recombination in fork progression in this situation was examined. Two questions were asked in this system: 1) Is the progression of the unblocked fork specifically reduced in the absence of genetic recombination (with a mutation in RecB)? and 2) Using chromatin IP, does this slow fork specifically recruit binding of a catalytically-dead Holliday-junction resolvase (RuvC)? The results from both experiments strongly support the conclusion that replication factories in some yet unknown manner are needed to stabilize the bidirectionally orientated replication forks. Although this strong conclusion indicates that the unblocked fork specifically creates DNA lesions, this approach does not unambiguously distinguish between damage resulting directly from fork collapse and damage caused by other aspects of defective DNA replication.

    1. Reviewer #2 (Public Review):


      This manuscript re-examines a distractor effect of decoy options on risky choice reported in previous research by re-analyzing data from previously published experiments that reported these effects. The previous studies reported that adding an unavailable decoy option to a choice set consisting of two available risky choices increased the discriminability between the two available risky choices, especially when the expected value difference between the two available risky options was small, by increasing the expected value of the unavailable distractor. The authors argue convincingly that the distractor effect is an artifact of two other confounding factors: one is that there is a covariance between the distractor's expected value and the subjective utility difference between the two targets; the second is that the expected value of the distractor alternative could covary with its relative position in the reward-probability space, and its relative position in the multi-attribute space could induce a well-known context effect. The first alternative explanation was established by comparing binary choice with and without the distractor present and finding the same effect in binary choice without any distractor present. The second was established by showing that the distractor effect was most pronounced when it was close to the higher-value target in the multi-attribute space, inadvertently producing a previously well-known attraction effect. These results clarify the role that an unavailable distractor plays in decisions between two risk alternatives.


      This is a very comprehensive and somewhat complex manuscript. It does a good job of detective work to get at the bottom of the distractor effect reported in previous articles (including this journal). It essentially contains two main sections. The first section is designed to establish the conclusion that the distractor effect is an artifact of a confounding variable, the additive utility difference between the two available choices, and generalized linear model analyses were used to make this point. The second section is designed to show that the distractor effect also covaries with a well-known context effect called the attraction effect, and they use mathematical modeling of choice and response time to understand this part. Different hypotheses about how the risk information was integrated tested by varying how the drift rate was calculated in a racing drift diffusion model for choice and response time. In particular, they contrasted a divisive expected value type of integration hypothesis with a selective attention type of additive utility hypothesis. They concluded from these mathematical modeling analyses that an additive utility model for integrating the risk information was used in these experiments to evaluate the risky gambles.

      Strengths the manuscript makes a very compelling case for the conclusion that the distractor effect was confounded with the additive utility difference between the available alternatives. This was achieved comparing the binary choice results, with and without the distractor, and finding little or no difference between these two conditions. The manuscript is also commendable for its rigorous mathematical modeling of the context effect of the distractor on the binary choices when the distractor was present.

      One weakness is that the contribution is somewhat narrowly focused with respect to the phenomenon that it addresses - the distractor effect in risky choice. However, I do think it is important for understanding this particular phenomenon. The other main weakness is the complexity of the manuscript. The manuscript is very long with numerous detailed statistical analyses and computational modeling analyses. Generally speaking, the authors did a good job describing and summarizing all these analyses, and they made effective use of figures to illustrate the ideas and conclusions. However, there are several spots that are somewhat difficult to follow (see specific comments), and the reader is pressed to think pretty hard and fairly long and with a lot of effort to absorb all the points.

      One other major concern I have regards the conclusion that the participants in these studies use an additive rather than a multiplicative rule to integrate the risk information. The additive rule is problematic in general because it fails to predict the reversal in the effect of probability on payoffs when the payoffs change sign. More specifically, increasing the probability of winning increases the probability of choosing an option when the payoff is positive, but the effect reverses when the payoff is negative. One needs to impose some pretty ad hoc assumptions to make the additive model account for this fundamental interaction between probability and payoff. Of course, the experiments reported here did not include negative payoffs, and so didn't run into this problem. In fact, when the payoffs are positive, it is possible to transform the multiplicative model to an additive model by a log transform. This transformation is only possible for the simple type of gamble investigated in this manuscript - a single amount to win with some probability of winning, otherwise win or lose nothing. If the gambles involved more than one outcome, then the theorist needs to deal with a sum of products and the log transform is no longer possible. For these reasons I am very skeptical about the general application of a summation rule for probability and value in risk choice. The authors do address this issue to some extent. They point out the abundance of other research supporting a multiplicative rule, and they speculate that the additive rule may have occurred within the restrictions of this special situation. The latter discussion is a good start, but I suggest that the authors discuss this fundamental issue in more depth.

    1. Reviewer #2 (Public Review):

      This paper describes a new concept of "axe-vascular coupling" whereby action potential traffic along white matter axons induces vasodilation in the mouse optic nerve. This is an initial report dissecting some of the mechanisms that are undoubtedly complex as in gray matter NVC. I like the novel AVC concept.

      Some minor corrections and suggestions:

      1) p3: "The cerebral white matter (WM) in the adult brain is particularly vulnerable to cerebrovascular diseases such as ischemia":this may be misleading since WM is actually far less vulnerable to ischemia than gray matter

      2) p4-5: "The ON exhibited a median of 175.8 pc/mm2 {plus minus} 35.7 pc/mm2, more than twice the number of pericytes observed in the corpus callosum [...] and lower than cortex ": this seems incorrect, the density in cortex is not significantly different than ON

      3) p5: what is the unit 'pc'? (A cellI I presume but please define at first use)

      4) p7 : "To evaluate if pericytes have and retain their contractile properties, we applied the vasoconstrictor U46619 (100 nM) for 15 min followed by acetylcholine (ACh - 100 μM) as a vasodilator": if they saw an effect, how would the authors know these were mediated my pericytes and not smooth muscle cells?

      5) in Fig. 3i there is a sharp step after U466... application: is this an artifact or evidence of a delayed constriction? Could a clearer trace be shown that does not confuse?

      6) Fig. 4I: what does "20% CAP (norm)" mean? Why not just mV for the y-axis? Also what pulse width was used for stimulation?

      7) Fig.5: it would be good to show both the CAPs (at various frequencies) and the vasorespones at 95% vs 20% O2. In particular, are the ONs able to sustain conduction at the higher frequencies (showing overlays as in 4I), and if not, could this at least partially account for the different responses at the two O2 levels?

      8) Fig. 6G,H is somewhat misleading as it implies no change in AVC, at odds with 6E. Suggest some clearer labeling to reduce confusion surrounding this very important point.

      9) P18 authors state radius of a MON is 150um but on p4 they say "150 μm - 200 μm thickness", pls clarify.

      10) p19-20: as part of their second messenger speculation authors may also want to include NO that has been shown to induce important effects in WM. Indeed, testing the tat uncoupling peptides could be interesting to see of oligodendroglial NMDARs have a similar singling arrangement with NOS as do neurons. This may have important implications for WM neuroprotective strategies in stroke that have typically focused on gray matter mechanisms.

    1. Reviewer #2 (Public Review):

      This study used serial block face scanning electron in the mouse posterior vermis. The analysis showed that Purkinje cell "naked" spines, are ~5% of all spines after wakefulness but grow to ~10% of all spines after sleep. Additional analysis revealed that the observed sleep-wake difference is best explained by a change in the number of "branched" synapses, Branched spines are proposed to convert to single spines during sleep. It is speculated that sleep promotes the pruning of branched synapses. This is a beautiful study that must have taken considerable effort in addition to expertise. No such data exist in the literature and the observations are interesting in light of the prior data from cortex published by the same group.

      Major critique:

      • The abstract and in particular the second half is very difficult to follow and should be rewritten. It might be easier to follow if the authors compare to previous work in cortex<br /> • The figures are very well done. However, I am missing a model diagram explaining the model proposed for changes in naked spine during the sleep-wake cycle and the proposed functional consequences.<br /> • The authors have previously studied the effect of sleep on the ultrastructure of glial cells, astrocytes and oligoes. This might be a separate study, but it would be of interest to discuss the role of Bergmann glial cells in synaptic plasticity. One major difference is that Bergmann glia express AMPA receptors, unlike cortical astrocytes and these are important for the proximity of astrocytic processes to synapses.

    1. Reviewer #2 (Public Review):

      This is an interesting study with a primary value in generating new transcriptional data sets for zebrafish hair cells and non-sensory cells in the inner ear. The data will, no doubt, be useful for future studies of hair cell function, development, and regeneration. The data also reveal transcriptional differences between similar cell types in different structures and transcriptional similarities between fish and mammalian cell types within analogous structures. Overall the strength of evidence in support of the results is strong.

    1. Reviewer #2 (Public Review):

      The authors present a genetic, physiological and cellular analysis of Drosophila mutants lacking one or both of the Drosophila homologs of the functionally uncharacterized c19orf12 gene. This gene is mutated in patients suffering from a familial neurodegenerative disorder called Neurodegeneration with Brain Iron Accumulation (NBIA).

      To this aim the authors extend a previous study based on in vivo RNAi in Drosophila by generating deletion mutants for nazo and CG3740, which encode the two fly c19orf12 homologs. Nazo single and nazo CG3740 double mutant flies are viable but show lifespan reduction and compromised climbing ability.<br /> While these results are generally credible they are methodologically not sound.<br /> The authors compare to "WT" controls but the method section refers to no wild type but rather to a w[1118] mutant, which is widely used as control. However, there is no record that the nazo and/or CG3740 mutants have been backcrossed in this control background. Statistics is missing on lifespan experiment and the documented climbing distances are not credible (26cm compared to 4cm in 4 sec for controls in Ref. 46).

      Lifespan reduction and climbing deficits at mid-age can be indicative of neurodegeneration or of developmental metabolic defects alike. The observed early-age mortality argues for a developmental rather than a degenerative effect. Comparing climbing capability at young age can sort this out and should at least be discussed.

      Surprising for genes, implicated in neurodegeneration, fly c19orf12 homologs are (predominantly) expressed in the gut. Accordingly, the authors performed comparative gut transcriptome analysis to find a number of lipid metabolism genes regulated. Microscopic inspection revealed lower gut lipid droplet (LD) abundance in nazo single and nazo CG3740 double mutants compared to controls. How they might be related to the regulated lipid metabolism genes remains unaddressed.

      The authors exclude an implication of the (gut) microbiome / the immune system, as well as abnormal food intake and of fatty acid absorption on this phenotype.<br /> Notably, the assay for fatty acid absorption is neither described in the methods section nor referenced or validated.

      Next the authors convincingly demonstrate that the nazo function on LDs is cell-autonomous in the gut by enterocyte-targeted expression of (i) a new (unvalidated) RNAi transgene and (ii) a nazo transgene in the nazo mutant background. To what extent the rescue of nazo function in the enterocytes reverts representative mutant phenotypes such as lifespan reduction, climbing ability or adipose tissue lipid storage remains unaddressed.

      The authors demonstrate that adipose tissue LDs and- correspondingly - organismal storage fat content is reduced in nazo deletion and global knockdown mutants, which causes starvation sensitivity. The central question, however, remains open: is this due to nazo function in the adipose tissue (where human c19orf12 is highly expressed) or an indirect effect of compromised nazo in the gut?

      The authors report some additional nazo/CG3740 mutant phenotypes such as oxidative stress sensitivity, elevated body H2O2 and an inflated crop in response to high fat diet (HFD). While these are interesting observations, they altogether do not advance the understanding of the gene(s) function(s). On the contrary, it appears counterintuitive, that flies with inflated crop on HFD due to a gut peristaltic defect (data not shown), manage to dynamical accumulated LDs in the gut as witnessed by Fig. 6B.

      Entry point to the mechanistic understanding of Nazo is the subcellular localization of the protein. The authors use overexpression of a (functionally unvalidated) tagged-Nazo in Drosophila tissue culture cells supplemented with fatty acid to trigger LD formation, to show that Nazo locates to LD contact sites of the ER. While this tissue culture system is widely used, in vivo data are required to substantiate this central finding. The myc-tagged, functionally validated rescue transgene offers an obvious tool for such an analysis.

      Next the authors demonstrate that the gut LD storage capacity is not generally limited in nazo mutants but can be reversibly expanded by dietary intervention. Based on this result the authors favour lipid catabolism over anabolism dysregulation to explain the LD depletion phenotype of nazo mutants and turn to genetic experiments to substantiate this hypothesis.

      Ubiquitous knockdown of Brummer/DmATGL is the only one out of three lipases tested (data of one not shown), which suppresses the nazo/CG3740 LD phenotype. The informational value of these experiments is compromised by the lack of essential controls; most importantly the consequences on gut LDs of knocking down these lipases in flies with normal nazo/CG3740 function. Also, ubiquitous lipase knockdown (instead of gat-targeted) limits the interpretation as indirect effects on gut LDs cannot be excluded.

      Overexpression of Perilipin-2, which shields LDs, is conceptually similar to the down-regulation of lipases. Accordingly, the authors show that ubiquitous overexpression of Plin-2 (but not of a different LD protein) partially suppresses the nazo LD phenotype. Again, the study design suffers from not showing the consequences of overexpression of these proteins on gut LDs of flies with normal nazo/CG3740 function. Without these data the specificity of the genetic interactions of nazo cannot be assessed.

      Central to the model of the authors is the lack of Nazo causing a decrease of Plin-2 protein abundance. This claim is poorly supported by the Western blot data presented Fig. 7C. Moreover, at least in adipose tissue Plin-2 has a LD-associated and a cytoplasmic pool. Accordingly, global abundance is a weak predictor for LD-associated Plin-2, which calls for alternative and complementary experimental approaches (e.g. in vivo imaging of tagged proteins, immunohistochemistry, co-IPs) to substantiate the working model of the authors.

    1. Reviewer #2 (Public Review):

      Amyloid-β precursor protein (APP) regulates synaptic activity in part through the release of secreted APP (sAPP) acting at cell-surface receptors. In 2019 two articles (Dinamarca et al, 2019; Rice et al, 2019) were published showing that sAPP binds with high affinity with GABAB receptors. These receptors regulate neuronal excitability and synaptic release. In the Rice et al. paper, it was concluded that sAPP plays a physiological role by regulating GABAB receptors by modulating synaptic transmission, consistent with the direct activation of these receptors by sAPP. This article has received major attention in the field of Alzheimer's disease and synaptic biology.

      The present work was designed to fully explore the functional consequences of sAPP binding to GABAB receptors, in particular, because it was unclear how a conformational change in SD1 - the region of GABAB receptors that binds sAPP - potentially induced by sAPP could increase GBR activity.<br /> The work does confirm that the peptide APP17 which derives from sAPP binds with nanomolar affinity with GABAB receptors. The authors use a diverse range of techniques, ranging from biophysical assays in recombinantly expressed receptors to electrophysiology and live imaging in cultured neurons, slices, and in vivo neuronal activity. In none of these assays, could the authors demonstrate any functional effect of sAPP mediated by an action on GABAB receptors.

      This work from a team that has exquisite knowledge of the different aspects of GABAB receptors represents an important and very convincing clarification for the field, and it would therefore be very useful if this information is rapidly available.

    1. Reviewer #2 (Public Review):

      In their current manuscript Hussmann et al., present a very detailed phenotypic analysis of the role of svep1 in lymphatic development in zebrafish. They show that svep1 is essential for the development of particular aspects of facial lymphatics (the FCLV and BLECs) in a fashion complementary to VEGF-C. Furthermore, they show that the loss of tie1 phenocopies svep1 mutants not only with respect to lymphatic defects but also in blood vessels (DLAV).

      Overall, the manuscript is clearly written, the experiments are carefully executed, and the quality of data is very high and support the author's main conclusions: 1) that Svep1 and Tie1 genetically interact during lymphatic and blood vessel development and 2) that this function is independent and complementary to VEGF-C. 3) The authors confirm and extend on a previous study (Jiang et al. 2020) showing that tie2 (tek) has no overt role in vascular development in zebrafish in blood as well as in lymphatic vessels.

      The strength of the paper lies in the careful combination and comparison of different mutant alleles and the use of state-of-the-art imaging. These analyses show that Svep1 and Tie1 interact at the genetic level. In vivo cell tracking experiments show that Tie1 and Svep1 regulate particular aspects of lymphatic cell migration.

      An obvious remaining question concerns the epistatic relationship and the molecular mechanism of Tie1/Svep1 interaction. The authors suggest a non-autonomous requirement of Svep1 in the ECM regulating the availability of Tie1 ligands (Ang-1/-2?) in LECs. Since bona fide ligands for Tie1 have not yet been identified in zebrafish further studies will be needed to test this model.

    1. Reviewer #2 (Public Review):

      The authors used Mendelian randomisation to study the relationships between metabolic traits and oral/oropharyngeal/head and neck cancers. This study was conducted as the relationships between these traits and cancers are unclear based on observational data. Evidence for relationships between these traits and cancers is inconclusive, which is a relevant finding in the context of previous observational data.

      Strengths include using large studies to develop the instrumental variables used in MR and examining multiple metabolic traits. Weaknesses include relatively low power to detect associations and a lack of discussion around any possible pleiotropy of SNPs associated with any of the metabolic traits. Based on these strengths and weaknesses, it is unclear whether the authors achieved their goal and whether the results support their conclusions.

      This work is relevant to researchers interested in oral cancers and their etiology. Several issues would need to be addressed to make the evidence more reliable.

    1. Reviewer #2 (Public Review):

      The work systematically reassesses fungal mi/miRNA-like characteristics and annotation confidence and identifies that many of the loci fail to meet the key points of the methods developed for animal or plant miRNAs. Therefore the authors establish a set of criteria suitable for the annotation of fungal miRNAs and provide a centralized annotation of identified mi/milRNA hairpin RNAs in fungi based on their established rules.

      Here are some comments and suggestions for the manuscript to be improved:<br /> 1. The title mentions "ancestral links", however, the main context of this paper does not include the evolution of fungal mi/milRNAs or show the origins of conserved mi/milRNAs in fungi. The authors are suggested to consider a more appropriate title for this work.<br /> 2. The work proposes a fungal mi/milRNAs hairpin precursor recovery pipeline with three minimal criteria to annotate fungal mi/milRNA loci, which allows nearly half of the loci to pass these rules. To highlight the innovation of this annotation, it is strongly suggested that the authors compare their established pipeline and criteria for fungi with those used in animal or plant miRNAs in detail, and emphasize the advantages of the established pipeline. A figure showing the established pipeline and detailed parameters is needed.<br /> 3. The established "standard rules" for fungal mi/milRNA annotation still require more evaluation. It would be better if there is experimental validation to improve confidence.

    1. Reviewer #2 (Public Review):

      Differences in protofilament and subunit helical-start numbers for in vitro polymerized and cellular microtubules have previously been well characterized. In this work, Guyomar et al. analyze the fine organization of tubulin dimers within the microtubule lattice using cryo-electron tomography and subtomogram averaging. Microtubules were assembled in vitro or within Xenopus egg cytoplasmic extracts and plunge frozen after addition of a kinesin motor domain to mark the position of tubulin dimers. By generating subtomogram averages of consecutive sections of each microtubule and manually annotating their lattice geometry, the authors quantified changes in lattice arrangement in individual microtubules. They found in vitro polymerized microtubules often contained multiple seams and lattice-type changes. In contrast, microtubules polymerized in the cytoplasmic extract more frequently contained a single seam and fewer lattice-type transitions.

      Overall, their segmented subtomogram averaging approach is appropriately used to identify regions of lattice-type transition and quantify their abundance. This study provides new data on how often small holes in the lattice occur and suggests that regulators of microtubule growth in cells also control lateral tubulin interactions. However, not all of the claims are well supported by their data and the presentation of their main conclusions could be improved.

    1. Reviewer #2 (Public Review):

      In this study, the authors were attempting to determine if early life exposure to specific olfactory cues leads to changes in lifespan. They exposed young mice to urine from male or female adult mice, or no urine for the control groups. They were also interested in determining if the Gao gene was responsible for any effect they found due to its impact on olfaction. They found that females exposed to female urine lived longer than control or male-exposed female mice, and there was no effect of exposure on male lifespan. These effects were found to be completely independent of the Gao gene.

      I felt the overall methods were good, and they had sufficient power to look at the lifespan effects. However, the authors used spent bedding from male and female mice as the source of the smell exposure, and I would worry that spent bedding would have traces of fecal matter in it. This could suggest that any effect they see would be due to microbiome differences from the bedding exposure, not the smell of urine.

      While the results are interesting, I'm not sure they will have a huge impact on the field. Early life exposures have previously been shown to affect aging and lifespan, and there were overall very minor effects seen of these olfactory exposures in female mice.

    1. Reviewer #2 (Public Review):

      This study represents an important contribution to our understanding of SARS-CoV-2 transmission dynamics in France, Europe and globally during the early pandemic in 2020 and the authors should be congratulated for tackling this important question. Through evaluation of the contributions of intra- and inter-regional transmission at global, continental, and domestic levels, the authors provided compelling, although as of yet correlative and incomplete, evidence towards how international travel restrictions reduced inter-regional transmission while permitting increased transmission intra-regionally. Unfortunately, however this work suffers from a number of serious analytical shortcomings, all of which can be overcome in a major revision and re-analysis.

      With this genomic epidemiology analysis, the authors disentangled the relative contributions of different geographic levels to transmission events in France and in Europe in the first two COVID-19 waves of 2020. By partitioning the analysis into three complementary, but distinct, geographic levels, the migration flows in and out of continents, countries in Europe, and regions in France were inferred using maximum likelihood ancestral state reconstruction. The major strengths of this paper were the inclusion of multiple geographic levels, the comparison of different rate symmetries in the ancestral character estimation, and the comprehensive qualitative descriptions of comparisons over time and geographies. However, there were also major weaknesses that need to be addressed and are described in more detail below. They include summing across replicates that were drawn with replacement and were not independent; inadequate justification for excluding underrepresented geographies; the assertion that positive correlation between intra-regional transmission and deaths validates the accuracy of the analysis; considering the framework the authors have chosen for this analysis the analysis would accommodate and benefit strongly from increasing the size of the sequence sets selected for analysis in each replicate; and the sparsity of quantitative (over qualitative or exploratory) comparisons and statistics in the reporting of results. In particular, it would greatly strengthen the paper if the authors could better evaluate the effect of travel restrictions on importations and exportations by testing hypotheses, quantifying changes in the presence of restrictions, or estimating inflection points in importation rates.

      General comments on the Background: Need to elaborate on how this study fits into the big picture in the first paragraph. Should discuss how phylodynamics contributes to understanding of viral outbreaks, SARS-CoV-2 epidemiology and viral evolution.

      The authors should consider a hypothesis driven framework for their analyses, for example considering the geographically central position of France what hypotheses stem from this considering sources of viral importations and destinations of exportations from/to Europe vs other international? Or other a priori expectations.

      To address the computational limits of phylogenetic reconstruction, 100 replicates of fewer than 1000 sequences each were sampled for each epidemic wave at each level. The inter- and intra-regional transmissions were averaged and then summed across replicates in order to compare the relative roles played by each geography towards transmission. While we see the logic in using the sum across replicates, this is highly likely to bias results, especially since in the methods, this is described as sampling with replacement between replicates (LX). The validity of summing replicates needs to be discussed and are likely most appropriately presented as mean or median. Also, these samples are quite small considering the computational capacity of the maximum likelihood tools being used. We recommend repeating the analysis with a substantially larger number of sequences per sample.

    1. Reviewer #2 (Public Review):

      The manuscript by Ge et al investigated the therapeutic benefits of the SGLT2 inhibitor empagliflozin in Alport syndrome (AS). They established the immortalized tubular cells and podocytes using wildtype (WT) mice and mice with AS. They showed that cultured human and mouse podocytes express similar levels of SGLT2 protein as compared to tubular cells. In vitro, they demonstrated that AS podocytes accumulate more lipid droplets and show increased levels of apoptosis in comparison to WT podocytes. Empagliflozin significantly reduces lipid droplets and apoptosis in AS podocytes. Furthermore, empagliflozin inhibits glucose/pyruvate-driven respiration in AS podocytes. In vivo, empagliflozin prolongs the lifespan of AS mice. Compared to untreated AS mice, empagliflozin improves kidney function and reduces the content of triglycerides and cholesterol esters in the kidney cortices of AS mice. Overall, the manuscript is nicely written, well-arranged, and easy to read. The experimental methods are reliable, and the conclusions are supported by the results.

    1. Reviewer #2 (Public Review):

      In this report, the authors have described the generation and characteristics of Cep78 mutant mice. Consistent with the phenotype observed in patients carrying the mutations in CEP78, Cep78 knock-out mice show degeneration in photoreceptors cells as well as defects in sperm. The author further shows the CEP78 protein can interact with IFT120 and TTC21a. Mutation in CEP78 results in a reduction of protein level of IFT120 and TTC21A and mislocalization of these two proteins, offering mechanistic insights into the sperm defects. Overall the manuscript is well written and easy to follow. Phenotyping is thorough. However, improvement of the background section is needed. In addition, some of the conclusion is not sufficiently supported by the data, warranting further analysis and/or additional experiments. The Cep78 KO mice model established by the author will be a useful model for further elucidating the disease mechanism in human and developing potential therapy.

      My comments are the following:<br /> 1. Introduction. The statement that "CRD usually exists with combination of immotile cilia defects in other systems" is not correct. CRD due to ciliopathy can have cilia-related syndromic defects in other systems but it is a relatively small portion of all CRDs and the most frequently mutated genes are not cilia-related genes, such as ABCA4, GUCY2D, CRX.<br /> 2. Introduction: Page 4 CNGB1 encodes channel protein and not a cilia gene. It should be removed since it does not fit.<br /> 3. Page 5, given the previous report of CEP78 patients with retina degeneration, hearing loss, and reduced infertility, the statement of "we report CE79 as a NEW causative gene for a distinct syndrome...TWO phenotypes....." Is not accurate.<br /> 4. Figure 1F, the OS of the cone seems shorter, which might be the reason for weaker arrestin staining in the mutant compared to the heterozygous. Also, it would be better to quantify the staining to substantiate the statement.<br /> 5. Figure 1K, panel with lower magnification would be useful to get a better sense of the overall structure defect of the retina. Is the defect observed in the cone as well?<br /> 6. Figure 2A, NPHP1 or other markers specifically label CC would be more useful to quantify the length of CC. Also need to provide a notation for the red arrows in Figure 2. In addition, the shape of CC in the mutant seems differ significantly from the control. It seems disorganized and swollen.<br /> 7. Evidence provided can only indicate direct interaction among CEP78/IFT20/TTC21A.

    1. Reviewer #2 (Public Review):

      I will first state that I am an ecologist that studies wind dispersal, and so my expertise lies in evaluating the determination of their results, the dispersal model, and the ecological significance - I cannot evaluate the PIV methods, although their results seem very reasonable based on other work! I believe this is a very strong paper that will have a lot of interest. In my opinion, it is the perfect demonstration of how to understand wind dispersal from a fundamental and ecological perspective. They first explore the aerodynamics of dandelion diaspores and how they change with the environment. Then they use this information to scale up to how this might affect dispersal across the landscape under different environmental conditions. I think the experiments they have conducted and the models they have included are excellent! I also really enjoyed that this work is the culmination of their body of work, where they have taken a step-by-step approach to convincing readers how dandelion diaspores disperse under different humidity conditions (see Seale et al. 2020 and 2022).

      The paper is very well written. The introduction lays out a very clear case as to why the environment should (and ultimately does) influence wind dispersal, and all of the relevant references are cited. It was nice to see them all in one place and is a great summary of the literature for those who are new to the field.

      The authors also claim that the environment can have an impact on dandelion dispersal by altering the shape of the diaspore (the pappus closes). This influences the terminal velocity and drag coefficient, and the authors used the appropriate PIV tests to determine that this is the case. They then go on to show that while wet conditions can decrease the terminal velocity which ultimately decreases dispersal distance, under wet/stormy conditions there are often increased wind speeds and this can actually increase dispersal because of increased wind speed. However this last point is a bit confusing to me based on the way the data is laid out.

      In all, I really enjoyed this paper! There is a lot to learn from this, and I look forward to reading it in print. I would encourage the authors to make a few updates to their text to make their conclusions crystal clear for readers!

    1. Reviewer #2 (Public Review):

      The data presented in this manuscript provide evidence that, in the ventral spinal cord of zebrafish embryos, "sister" V2a excitatory and V2b inhibitory neurons, which arise from common vsx1+ progenitors, extend descending, ipsilateral axons that, although differing in length, remain close to one another. Because of this alignment, V2a and V2b neurons could contribute to a common microcircuit, by receiving inputs from common synaptic circuits, forming synapses on one another, or projecting to common synaptic targets. However, a series of electrophysiological and optogenetic tests exclude these possibilities and indicate that, instead, they receive inputs from distinct sources, they do not engage in synaptic signaling with one another, and they have distinct, downstream synaptic targets. This differs from the mouse cortex, in which clonally related neurons appear to preferentially form connections within a shared microcircuit.

      The chief strengths of this work include the imaging data, which nicely reveal the locations and morphologies of sister V2a/b neurons, and the electrophysiological experiments, which provide compelling evidence that sister V2a/b neurons do not function within a shared microcircuit.

      The study does have some limitations. First, V2a/V2b sister pairs are not obligate. Instead, about 25% of V2b neurons arise from a vsx1+ progenitor division that also produces a V2s neuron instead of a V2a neuron. To distinguish between these outcomes, the authors use the transient expression of a vsx1:EGFP reporter to label clonal pairs combined with a chx10:Red reporter to label V2a neurons. For the optogenetic experiments, however, the authors were not able to use the V2a neuron marker because they were limited by the reporters available to them. Thus, there is a possibility that some sister neurons tested were V2b/s rather than V2a/b. Second, the electrophysiological data are not paired with examinations of synaptic contacts using light or electron microscopy. Third, the circuits in which V2a and V2b neurons function are incompletely understood, and so knowledge of the synaptic inputs and downstream targets is limited.

      On balance, the limitations of the study are rather minor. The manuscript is nicely written, the figures are presented clearly and logically, and the data are sufficient to support the claims and conclusions made by the authors. The results extend our knowledge of developmental strategies used to form neural circuits.

    1. Reviewer #2 (Public Review):

      Miyakoshi et al. investigated the function of the small RNA GlnZ in E. coli and Salmonella. GlnZ originates from the 3'UTR of the glnA mRNA that encodes glutamine synthetase (GS), the central enzyme of nitrogen assimilation in bacteria. It has been confirmed that the processing of glnA and hence GlnZ formation involves Hfq and RNaseE. The authors also reveal that GlnZ regulates the sucA gene encoding the E1o component of 2-oxoglutarate dehydrogenase (OGDH) by complementary base pairing. As 2-OG is part of the TCA cycle as well as a precursor of the GS/GOGAT cycle, GlnZ appears to function as a major element to control carbon flow from the TCA cycle to this nitrogen assimilation pathway. This is an astonishing finding as the glnA gene and many other aspects of nitrogen assimilation via GS are rather well-investigated. Obviously central regulators can still be discovered, even on mRNAs that have been investigated for decades.

      The authors present a nice piece of molecular biology work which justifies the major conclusion that GlnZ is formed by processing of glnA and regulates the sucA gene post-transcriptionally. In general, the manuscript is well-written and the data are clearly presented. The figures are great and allow the reader to easily follow the descriptions. Nevertheless, some aspects referring to the actual control of metabolism could be improved. For instance, the authors claim to have proven that "GlnZ represses the expression of SucA TO REDIRECT the carbon flow from the TCA cycle to the nitrogen assimilation pathway". However, the manuscript does not contain data, e.g. of metabolite profiling using glnZ mutants, that really confirm this statement. Even though GlnZ has a significant effect on SucA abundance it is rather weak, especially in E. coli (Fig. 4B). Of course, this is not uncommon for sRNA-dependent expression control and there is no doubt about the importance of the here presented finding. The authors should either include data that indeed show any effect on 2-OG levels and/or metabolic flux through OGDH or at least temper their conclusion and say that their findings only indicate this.

    1. Reviewer #2 (Public Review):

      Susswein et al. analyze a fine-scale, novel data stream of human mobility, openly available from Safegraph, based on the usage of mobile apps with GPS and sampled from over 45 million smartphone devices. They define a metric $\sigma_{it}$, properly normalized, that quantifies the propensity for visits to indoor locations relative to outdoor locations in a given county $i$ at week $t$. For each pair of counties $i$ and $j$, they compute the Pearson correlation coefficient $\rho_{ij}$ between the corresponding $\sigma$ metrics. This generates a correlation matrix that can be interpreted as the adjacency matrix of a network. They then perform community detection on this network/matrix, effectively clustering together time series that are correlated. This identifies three main clusters of counties, characterized geographically as either in the north of the country, in the south of the country, and possibly in tourism active areas. They then show, via a simple model, how including over-simplified models of seasonality may affect infectious disease models.

      This work is very interesting for the infectious disease modeling community, as it addresses a complex problem introducing a new data stream.

      This work builds on several strengths, among which:<br /> It is the first analysis of the Safegraph dataset to capture seasonality in indoor behavior.<br /> It provides a simple metric to quantify indoor activity, that thanks to the dataset can be computed with a high level of spatial detail.<br /> It aims at characterizing clusters of counties with a similar pattern of indoor activity.<br /> It aims at quantifying the impact of neglecting finer-scale patterns of seasonality, for example considering seasonality to be homogeneous at the US level.

      At the same time, it presents several weaknesses that should be addressed to improve the methodology, its results, and the implication:<br /> There is no quantitative comparison of the newly introduced metric for indoor activity with other proxies of seasonality (e.g. temperature or relative humidity). The (dis)similarity with other proxies may help in assessing the importance of this metric, showing why it can not be exchanged with other data sources (like temperature data) that are widely available and are not affected by sampling issues (more on that later).<br /> A major flow of the analysis is to perform community detection on a network defined by the correlation between time series with an algorithm that is based on modularity optimization. As explained in Macmahon et al.[1], all modularity optimization methods rely on null assumptions that in the case of correlation between time series are violated. Therefore, there is a very strong potential bias in their results that is not accounted for. Possible solutions could be to proceed via the methodology presented in [1] or via a different type of algorithm (e.g. Infomap [2]). In both cases, as the network is thresholded (considering only a correlation larger than 0.9), a more quantitative assessment of the impact of the threshold value should be included.<br /> It is not clear what is the added value of the data on indoor activity, as no fitting to real data is performed. Although this may be considered beyond the scope of this paper, I think it would be crucial to quantify how much a data-informed model would better describe real epidemic data (for example in the case of COVID-19). For now, only the impact of neglecting heterogeneity in indoor activity is shown, comparing a model with region-average parameters vs a model with county-level average parameters. Given that the dataset comes with potential bias in sampling (more on this later) it would be good to assess its goodness in predicting real epidemic spread.<br /> When showing results from different models, no visible errors are shown on the plot. How have the errors been estimated?<br /> The dataset is presented as representative of the US population. However, this has not been assessed over time. As adherence to social distancing is influenced by several socio-economic determinants the lack of representativity in certain strata of the population at a given time may introduce an important bias in the dataset. Although this is an inherent limitation of the dataset, it should be discussed in the paper more thoroughly.

      In conclusion, I think that the methodology should be revised to account for the fact that the analysis is performed on a correlation matrix. Capturing seasonal patterns of indoor activity can help in tackling the crucial problem of seasonality in human behavior. This could help in identifying effective strategies of disease containment able to curb disease spread at a lower societal cost than fully-fledged lockdowns.

      References<br /> [1] Mel MacMahon and Diego Garlaschelli Phys. Rev. X 5, 021006 (2015).<br /> [2] Martin Rosvall and Carl T. Bergstrom PNAS 105, 1118 (2008).

    1. Reviewer #2 (Public Review):

      The developmental mechanisms underlying insect polyphenisms are understood for only a few species. Previous studies in pea aphids and planthoppers have shown that insulin signalling is important for differences in wing morphs across environmental conditions. In the pea aphid, mothers that are crowded produce a high proportion of offspring with wings, while mothers housed alone produce offspring without wings. The authors emphasise that in the pea aphid wing loss is a novel trait, and work to identify the developmental processes that lead to wing loss. They find that wing loss is induced by autophagy of the wing disc in the first instar nymphs. Using a transcriptomics approach, they identify a candidate gene, REPTOR2, whose expression is enriched in nymphs destined to become wingless. REPTOR2 is a novel gene that has arisen from duplication in REPTOR. They further demonstrate that reducing REPTOR2 expression by RNAi increases the proportion of winged nymphs. Similarly, reducing the target of rapamycin signalling or feeding mothers on a low-protein diet decreased the proportion of winged nymphs. The authors conclude from these studies that in crowded mothers, high TOR signalling represses REPTOR2 activity leading to reduced autophagy in the wing discs.

      Strengths:<br /> 1. The authors have outlined very clear hypotheses and aims, which makes the arguments in the text very easy to follow.<br /> 2. This study is very carefully conducted, and the authors use multiple lines of approach to validate their claims (eg confocal imaging of wing discs to examine ATG8 expression and TUNEL staining to differentiate between autophagy or apoptosis respectively, followed up by qPCR for autophagy and apoptosis genes).<br /> 3. Experiments are appropriately quantified and are backed by statistical tests.<br /> 4. The results lend excellent support to the author's claims.

      Weaknesses: The authors do not make a direct link between TOR and REPTOR2 signalling. This seems important since REPTOR2 is a novel gene that arose from the duplication of REPTOR.

    1. Reviewer #2 (Public Review):

      Microtubules are regarded as dynamic tracks for kinesin and dynein motors that generate force for moving cargoes through cells, but microtubules also act as motors themselves by generating force from outward splaying protofilaments at depolymerizing ends. Force from depolymerization has been demonstrated in vitro and is thought to contribute to chromosome movement and other contexts in cells. Although this model has been in the field for many years, key questions have remained unanswered, including the mechanism of force generation, how force generated might be regulated in cells, and how this system might be tuned across cellular contexts or organisms. The barrier is that we lack an understanding of experimental conditions that can be used to control protofilament shape and energetics. This study by Murray and colleagues makes an important advance towards overcoming that barrier.

      This study builds on previous work from the authors where they developed a system to directly measure forces generated by outward curling protofilaments at depolymerizing microtubule ends. That study showed for the first time that protofilaments act like elastic springs and related the generated force to the estimated energy contained in the microtubule lattice. Furthermore, they showed that slowing polymerization rate did not diminish force generation. That study used recombinant yeast tubulin, including a 6x histidine tag on beta tubulin that created attachment points for the bead on the microtubule lattice. The current study extends that system to show that work output is related to the length of protofilament curls.

      Murray and colleagues show this by manipulating curls in two ways - using bovine brain tubulin instead of yeast tubulin and altering magnesium concentration. Previous EM studies indicated that protofilaments on depolymerizing bovine microtubules have similar curvature but are shorter. The authors here use a blend of bovine brain tubulin and bead-linked recombinant yeast tubulin with the 6x histidine tag in their in vitro system and find smaller deflections of the laser-trapped bead than previously observed with pure yeast tubulin. A concern with comparing this heterogeneous bovine/yeast system to the previous work with homogeneous yeast tubulin is that density of 6x histidine-tagged tubulin subunits is likely to be different between the two systems. Also, the rate of incorporation of 6x histidine yeast tubulin into bovine microtubules in the current study may be different from the rate of incorporation into yeast microtubules in the previous study. These differences could lead to changes in the strength of bead attachment to the microtubule lattice and alter the compliance of the bead to deflection by curling protofilaments. These possibilities and lattice attachment strength are not explored in this study, raising concerns about comparing the two systems.

      The authors go on to show that magnesium increases bead deflection and work output from the system. The use of magnesium was motivated by earlier studies which showed that increasing magnesium speeds up depolymerization and increases the lengths of protofilament curls. The use of magnesium here provides the first evidence that work output can be tuned biochemically. This is an important finding. The authors then go on to show that the effect of magnesium on bead deflection can be separated from its effect on depolymerization speed. They do this by proteolytically removing the beta tubulin tail domain, which previous studies had shown to be necessary to mediate the magnesium effect on depolymerization rate. The authors arrive at a conclusion that magnesium must promote protofilament work output by increasing their lengths. How magnesium might do this remains unanswered. The mechanistic insight from the magnesium experiments ends there, but the authors discuss possible roles for magnesium in strengthening longitudinal interactions within protofilaments or perhaps complexing with the GDP nucleotide at the exchangeable site, although that seems less likely at the concentrations in these experiments.

      The major conclusion of the study is the finding that work output from curling protofilaments is a tunable system. The examples here demonstrate tuning by tubulin composition and by divalent cations. Whether these examples relate to tuning in biological systems will be an important next question and could expand our appreciation for the versatility of depolymerizing microtubules as a motor.

    1. Reviewer #2 (Public Review):

      This paper has collected an impressive data set of the visual response properties of neurons in the visual layers of the mouse superior colliculus. There are 3 main findings of the study. First, the authors identify 24 functional classes of neurons based on the clustering of each neuron's visual response properties. Second, unlike in the retina where each cell type is regularly spaced, functional classes in the superior colliculus appear to cluster near each other. Third, visual representation has a lower dimensionality in the superior colliculus compared to the retina. The dataset has the potential to support the conclusions of the paper, but further analysis is required to make the claims convincing.


      The main strength of the paper is its impressive dataset of more than 5000 neurons from the visual layers of the superior colliculus. This data set includes recordings from both an interesting set of genetically labelled classes of cells and from a reasonably large portion of the superior colliculus. This dataset offers the opportunity to support the major claims of the paper. This includes i) the identification of 24 functional classes of neurons, ii) the intriguing possibility that functional classes form local patches within the superior colliculus and iii) that the representation of visual information in the superior colliculus has a lower dimensionality compared to the retina.


      The weakness of the paper is that its main claims are not adequately supported by the presented data or analysis. First, support for the existence of 24 functional classes is not clear enough. Our major concern is that it is not clear that each class of neurons was distributed across different mice. Are certain cell types overrepresented in individual animals, or do you find examples of each cell type in most animals? In addition, it should be made explicit how the responses of each genetically labeled class of neurons are distributed among the 24 functional clusters. Second, the analysis of the spatial clustering of functional cell types is not complete. Do the same functional clusters sample the same retinotopic locations in different mice? How are clusters of the functional type distributed in visual space? Third, the lower dimensionality of representation in the superior colliculus may be the result of selective projections of retinal ganglion cells, not all retinal ganglion cell types project to the superior colliculus. Please estimate the dimensionality of the visual representation of those retinal ganglion cell types that projects to the superior colliculus.

    1. Reviewer #2 (Public Review):

      The data presented in this manuscript are sound but rather descriptive. The contribution - as presented - is mostly of a technical nature. The authors correctly state that anti-GFP nanobodies, while used extensively across many model organisms, have limited utility for in vivo applications when the GFP-tagged protein in question displays abnormal behavior or is non-functional. The creation of nanobodies that are uniquely specific for the protein(s) of interest is therefore a significant improvement, especially since the Sallimus and Projectin-specific reagents reported here react with PFA-fixed material. At least one of these nanobodies, when expressed in vivo, decorates the appropriate target. The source of antigens used for the construction of the nanobody library is Drosophila-derived. The extent of homology of Drosophila Sallimus and Projectin with related proteins in other species is not discussed. Whether the nanobodies reported here would be useful in other (closely related?) species, therefore, remains to be established. For those studying muscle biology in Drosophila, the nanobodies described here will be publicly available as cDNAs. Ease of production implies a readily shared and standardized resource for the field.

      Further characterization of these nanobodies by biochemical methods such as immunoblotting would be challenging, given the size of the target proteins. In view of the technical nature of this manuscript, the authors should perhaps critically discuss the distinction between bulky GFP tags versus the much smaller epitope tags and the nanobodies that recognize them, although this was covered in a recent eLife paper from the Perrimon lab. Insertion of small tags, in conjunction with nanobodies that recognize them, would be less perturbing than the much bulkier GFP tag and lend itself to genome-wide applications. Creating nanobodies uniquely specific for each protein encoded in the Drosophila genome is not realistic, and the targeted approach deployed here is obviously valuable.

      The authors apply two different approaches to characterize the newly generated Nanobodies: more or less conventional immunohistochemistry with fluorescently labeled nanobodies, and in vivo expression of nanobodies fused to the fluorescent neongreen protein. The superiority of nanobodies in terms of tissue penetration has been shown by others in a direct comparison of intact fluorescently labeled immunoglobulins versus nanobodies. The authors state that in vivo labeling with nanobody fusions "thus far was done only with nanobodies against GFP, mCherry or short epitope tags." There is no fundamental difference between these recognition events and what the authors report for their Sallimus and Projectin-specific reagents. The section that starts at line 304 is thus a little bit of a 'straw man'. There is no reason to assume that a nanobody that recognizes a muscle protein would behave differently than a nanobody that would recognize that same protein (or another) when epitope- or GFP-tagged. What might be interesting is to examine the behavior of these muscle-specific nanobodies in the course of muscle contraction/relaxation: are there conformational alterations that promote dissociation of bound nanobodies? Do different nanobodies display discrete behavior in this regard? The manuscript is silent on how muscles behave in live L3 larvae. The FRAP experiment seems to suggest that not much is happening, but the text refers to the contraction of larval sarcomeres from 8.5 µM to 4.5 µM. Does the in vivo expressed nanobody remain stably bound during this contraction/relaxation cycle? What about the other nanobodies reported in this manuscript? Since the larval motion was reduced by exposure to diethylether, have the authors considered imaging the contractive cycle in the absence of such exposure?

    1. Reviewer #2 (Public Review):

      This is a very interesting paper that described how multiple kinases regulate the phase separation of Cdc15 and thus impact its localization and function during cytokinesis. The authors build upon their prior research to show that Cdc15 is phosphorylated in its intrinsically disordered region at multiple sites by different kinases. Molecular simulations suggest that phosphorylation of Cdc15 impacts its F-BAR domain's ability to interact with the membrane. Indeed, the authors show that non-phosphorylatable Cdc15 mutants appear in larger dynamic clusters in the cells and also increase the recruitment of cytokinetic proteins to the actomyosin ring. Furthermore, the authors show that the purified Cdc15 intrinsically disordered region undergoes phase separation when treated with a phosphatase. Also, the phase-separated region can recruit cytokinetic proteins that are known interacting partners of Cdc15. Overall, this is a very well-designed study that provides a deep mechanistic insight into how the Cdc15 scaffold conformation is regulated so that it can bind other proteins and interact with the plasma membrane to facilitate cytokinesis. However, the authors do not show if the sites identified here are specifically involved in phase separation. The authors provide evidence that Cdc15 undergoes phase separation when dephosphorylated by a phosphatase. However, it is not shown if dephosphorylation at the sites identified is indeed responsible for the phase separation. It would be helpful to show whether the purified cdc15-31A mutant protein also undergoes phase separation and increased interaction with cytokinetic proteins even in the absence of phosphatase treatment. This would provide strong evidence that indeed the kinases phosphorylate the identified sites to prevent phase separation.

    1. Reviewer #2 (Public Review):

      This manuscript addresses the broad question of when humans use different learning and memory systems in the service of decision-making. Previous studies have shown that, even in tasks that can be performed well using incremental trial-and-error learning, choices can sometimes be based on memories of individual past episodes. This manuscript asks what determines the balance between incremental learning and episodic memory, and specifically tests the idea that the uncertainty associated with each alters the balance between them in a rational way. Using a task that can separate the influence of incremental learning and episodic memory on choice in two large online samples, several lines of evidence supporting this hypothesis are reported. People are more likely to rely on episodic memory in more volatile environments when incremental learning is more uncertain and during periods of increased uncertainty within a given environment. Individuals with more accurate episodic memories are also more likely to rely on episodic memory and less likely to rely on incremental learning. These data are compelling, even more so because all of the main findings are directly replicated in a second sample. These data extend the notion of uncertainty-based arbitration between different forms of learning/memory, which has been proposed and evaluated in other contexts, to the case of episodic memory versus incremental learning.

      The weaknesses in the paper are mostly minor. One potential weakness is the nature of the online sample. Many participants apparently did not respond to the volatility manipulation, making it impossible to test whether this altered their choices. It is unclear whether this is a feature of online samples (where people can be distracted, unmotivated, etc.) or of human performance more generally.

    1. Reviewer #2 (Public Review):

      Humans learn about the world both directly, by interacting with it, and indirectly, by gathering information from others. There has been a longstanding debate about the extent to which social learning relies on specialized mechanisms that are distinct from those that support learning through direct interaction with the environment. In this work, the authors approach this question using an elegant within-subjects design that enables direct comparisons between how participants use information from social and non-social sources. Although the information presented in both conditions had the same underlying structure, participants tracked the performance of the social cue more accurately and changed their estimates less as a function of prediction error. Further, univariate activity in two regions-dmPFC and pTPJ-tracked participants' confidence judgments more closely in the social than in the non-social condition, and multivariate patterns of activation in these regions contained information about the identity of the social cues.

      Overall, the experimental approach and model used in this paper are very promising. However, after reading the paper, I found myself wanting additional insight into what these condition differences mean, and how to place this work in the context of prior literature on this debate. In addition, some additional analyses would be useful to support the key claims of the paper.

      (1) The framing should be reworked to place this work in the context of prior computational work on social learning. Some potentially relevant examples:

      - Shafto, Goodman & Frank (2012) provide a computational account of the domain-specific inductive biases that support social learning. In brief, what makes social learning special is that we have an intuitive theory of how other people's unobservable mental states lead to their observable actions, and we use this intuitive theory to actively interpret social information. (There is also a wealth of behavioral evidence in children to support this account; for a review, see Gweon, 2021).<br /> - Heyes (2012) provides a leaner account, arguing that social and non-social learning are supported by a common associative learning mechanism, and what distinguishes social from non-social learning is the input mechanism. Social learning becomes distinctively "social" to the extent that organisms are biased or attuned to social information.

      I highlight these papers because they go a step beyond asking whether there is any difference between mechanisms that support social and nonsocial learning-they also provide concrete proposals about what that difference might be, and what might be shared. I would like to see this work move in a similar direction.

      (2) The results imply that dmPFC and pTPJ differentiate between learning from social and non-social sources. However, more work needs to be done to rule out simpler, deflationary accounts. In particular, the condition differences observed in dmPFC and pTPJ might reflect low-level differences between the two conditions. For example, the social task could simply have been more engaging to participants, or the social predictors may have been more visually distinct from one another than the fruits.

      References<br /> (In the interest of transparency: I am not an author on these papers.)

      Gweon, H. (2021). Inferential social learning: how humans learn from others and help others learn. PsyArXiv. https://doi.org/10.31234/osf.io/8n34t

      Heyes, C. (2012). What's social about social learning?. Journal of Comparative Psychology, 126(2), 193.

      Shafto, P., Goodman, N. D., & Frank, M. C. (2012). Learning from others: The consequences of psychological reasoning for human learning. Perspectives on Psychological Science, 7(4), 341-351.

    1. Reviewer #2 (Public Review):

      This study by Nguyen and Voeltz uses proximity biotinylation and advanced imaging to elucidate roles for a lipid-metabolizing enzyme in controlling sites of mitochondrial fusion and fission. Using proximity biotinylation, they identify ABHD16A, which they propose to rename Aphyd, as an ER-resident protein close to mitochondrial fusion and fission sites. They find that knockdown and overexpression of this protein affects mitochondrial morphology and rates of mitochondrial constriction and subsequent fusion and fission. They also find that mutation of two different catalytic domains within ABHD16A have similar but non-identical effects in rescue experiments of siRNA-induced phenotypes. Broadly speaking, the hydrolase domain, known to deacylate phospholipids to form lysophospholipids (primarily phosphatidylserine to lysoPS), was more important for the phenotypes, but roles were also required for the acyltransferase domain. Perturbation of lipid transfer protein activity implicated the PS/PI4P transporter ORP8 in this pathway, strongly suggesting a specific role for ABHD16A in modulating PS metabolism at these sites to promote the mitochondrial constriction, fission, and fusion machineries. This focused study builds a rigorous and compelling story centered around the role a lipid-modifying enzyme in an interesting and important cellular behavior, namely how sites of mitochondrial fission and fusion are defined. Overall, this important study presents a compelling new model for understanding how specific local lipid metabolism at ER-mitochondria contact sites could facilitate mitochondrial fission and fusion events.

    1. Reviewer #2 (Public Review):

      The data presented support the conclusions of the paper, and my concerns are largely conceptional in how we understand this data in the context of malaria infection in vaccination in endemic areas

      1) The data is presented based on the idea that antigen uptake and presentation differ between particle and soluble antigens, and that during malaria infection particle uptake is more important due to circulating iRBCs. However, during parasite invasion of RBCs, the parasite sheds large amounts of antigen into the circulation, at least some of which would then be found in a soluble form in the circulation. Can the authors comment on this aspect of infection and if/how this may impact the interpretation of results? Do authors assume that any soluble antigen taken up and presented (via DCs?) during infection would be impacted as for GP66 soluble antigen? Or could an interaction on immune responses where the antigen is presented via both particle and soluble pathways?

      2) Impact of particle antigen opsonisation on antigen uptake and presentation. The authors use parasites isolated from mice who have been infected for 6-7 days to investigate the ability of different subsets to update particle antigens. At this time point, have mice developed antibody responses that opsonise these parasites, or are antibody levels low and parasites opsonised? Would opsonised parasites, such as those coated with sera from children in a setting of chronic infection, have a different pattern/ability to be opsonised by different immune cell subsets? And/or would opsonisation change how the DC and other cell types are processing/presenting antigens? While these issues could be addressed experimentally either now or in the future, the manuscript should at least consider this issue because, during a human infection in areas of high exposure, individuals are likely to have reasonable levels of antibodies with opsonised parasites circulating.

      3) While authors show that malaria infection disrupts the response to soluble antigens, the relevance directly to vaccination should be considered carefully, specifically because vaccines of soluble antigens are largely given alongside adjuvants which also will modulate DC function. Again, this could be addressed experimentally now or in the future, but definitely should be mentioned and considered when interpreting the results.

    1. Reviewer #2 (Public Review):

      In this manuscript, Najer et al., perform a comprehensive bioinformatic analysis of SARS-CoV-2 sequences available from public repositories. Through a comparison with the genome sequence of the original Wuhan 2020 strain, they identify the total accumulation of non-synonymous mutations as a predictor of the evolution of new strains. The manuscript provides data for three structural proteins - spike (S), membrane (M), and envelope (E) proteins, as well as data for the non-structural RNA-dependent RNA polymerase (RDRp) protein that serves as a negative control. However, the predictivity of this approach is most marked only for the Omicron variant, with considerable variation in the predictive power of SARS-CoV-2 proteins for other variants. Focusing on a spike, the method does not detect the alpha variant or delta variant surges, which were mostly driven by changes in spike protein, although the level of sequencing data available for the delta variant might have been less. Notably, although the authors conclude that other parameters such as the ratio of non-synonymous to synonymous mutations or the rate of accumulation of non-synonymous mutations are not predictive, they appear to have similar success in predicting the omicron surge.

    1. Reviewer #2 (Public Review):

      Goto and Miyamachi aimed to use fiber photometry to chronically record the activity of arcuate kisspeptin neurons, widely accepted as the GnRH pulse generator responsible for reproductive potential, to determine whether changes in their activity occur during the transition to reproductive senescence in female mice. The authors report that reduced estrous cycle regularity in aging mice is accompanied by changes in the amplitude, but not the frequency, of kisspeptin events. They conclude that the reduction in kisspeptin event amplitude may explain prior results showing reduced LH pulse amplitude in aged rats, potentially due to a reduction in kisspeptin expression. The following is a description of the strengths and weaknesses of this study.

      Strengths: Fiber photometry recordings of kisspeptin cells in unanesthetized, freely moving mice at multiple time points over a period of months are technically impressive and a strong approach for interrogating changes in kisspeptin cell physiology that may control the reproductive lifespan of mice.

      Weaknesses: Although the approach to use chronic imaging of kisspeptin cells from the same animal from 6 months to 15-18 months is impactful; this has only been conducted in two animals. The correlation between LH pulsatile secretion and kisspeptin activity has been well characterized in mice of reproductive ages in prior reports, however, no accompanying LH pulse measurements have been included in this study, and it is possible that the relationship between kisspeptin activity and LH secretion changes during the transition to acyclicity. The paper lacks a clear description of the parameters used to define acyclicity and to affirm that mice have reached reproductive senescence. Finally, the paper lacks histological analysis of the recorded kisspeptin cells, and although the viral vector used in this study has been well characterized, there is a potential for cytotoxicity from repeated imaging and long-term transfection of the vector.

    1. Reviewer #2 (Public Review):

      In this manuscript the authors build upon their previous work describing the structure of the iron efflux pump ferroportin. Here they examine ferroportin's capacity to bind and transport calcium ions. Previous studies indicated a binding site for calcium in Fpn and suggested that calcium binding was needed for iron efflux, while other studies found no requirement for calcium in iron efflux. Here the authors use cryo-EM to structurally characterize a calcium-bound form of Fpn and compare this form to iron- and hepcicin-bound Fpn structures. Using site directed mutagenesis, they functionally characterized the calcium binding site and kinetics of calcium transport and its effects on Fe(II) and Co(II) transport. They report that Ca2+ is transported by Fpn proteoliposomes and Fpn-overexpressing HEK cells, that Ca2+ uptake has little effect on Fe/Co transport, and that Fe/Co efflux inhibits Ca transport.

      The data reported here appear to be of high quality and are convincing; the experimental design is excellent and the necessary controls are appropriately employed. A couple of issues need clarification in the text. FPN is clearly an iron efflux pump and these studies make clear that Fpn can also import Ca2+, although it does not appear to function as an Fe2+-Ca2+ antiporter. What is less clear is whether Fpn will transport calcium bi-directionally. A further question that needs explaining is why bind and transport calcium? Cells have a high capacity for calcium flux independent of Fpn. Is there a physiological importance to this activity?

    1. Reviewer #2 (Public Review):

      In this study, the authors used an audiobook listening paradigm and encoding analysis of MEG to examine the independent contributions to MEG responses of putative acoustic and phoneme-level linguistic features in speech and their modulation by higher-level sentence/discourse constraints and language proficiency. The results indicate that:

      1) Acoustic and phoneme features do indeed make independent contributions to MEG responses in frontotemporal language regions (with a left-hemisphere bias for phoneme features).<br /> 2) Brain responses to acoustic and phoneme features are enhanced when sentence/discourse constraints are low (i.e. when word entropy is high).<br /> 3) While brain responses to phoneme features are enhanced when the language is comprehended (or word entropy is high), the opposite is observed for acoustic features.

      These results are taken to support widely held views on the nature of information flow during language processing. On the one hand, processing is hierarchical, consistent with finding 1 above. On the other hand, information flow between lower and high-levels of language processing is also flexible and interactive (finding 2) and modulated by behavioural goals (finding 3).

      This is a methodologically sophisticated study with useful findings that I think will be of interest to the burgeoning community investigating 'neural speech tracking' and also to the wider community interested in language processing and predictive coding. Moreover, the evidence appears convincing.

      I thought the impact was somewhat limited by the results presentation, which I think missed some key details and made the study somewhat hard to follow (but this issue can be addressed).

      Perhaps more major, I do wonder about the novelty of the study as each of the main findings has precedent in the literature. Finding 1 (e.g. Brodbeck, Simon et al.), Finding 2 (e.g. Broderick, Lalor et al.; Molinaro et al.), Finding 3 (e.g. Brodbeck, Simon et al. although here the manipulation of behavioural goals was through a cocktail party listening manipulation and there were was no opposing modulation of acoustic vs phoneme level representations). Thus, while the study appears well executed, overall I am unsure how significant the advance is. Related to this point, the study's findings and theoretical interpretations (e.g. the brain as a hierarchical 'filter') are consistent with widely held views of language processing (at least within cognitive neuroscience) and so again I question the potential advance of the study.

    1. Reviewer #2 (Public Review):

      This study contains a huge amount of data and the images are of high quality. However, the conclusions are not really well supported. The authors may have reached too far from their results. The roles of SHR, SCR and SCL23 in the shoot apex are not really clarified.

      The manuscript by Bahafid et al., reports a study of the functions of SHORTROOT (SHR), a well-established root development regulator in the shoot apical meristem (SAM) development with focus on lateral organ initiation. A large amount of data is included in this paper. This study highly depends on imaging, and the images are in general of very good quality. The authors show reciprocal interactions between SHR and SCR with auxin/MP. There are also a large amount of genetic interactions among several genes, including WUS and CLV3. Although the study provides a vast amount of data, the conclusions are not so well supported. There seem to be many interactions, at the protein level, and at the transcriptional regulation level, but the conclusion is nevertheless ambiguous.

    1. Reviewer #2 (Public Review):

      Sørensen and colleagues performed a comprehensive analysis aiming to find how DNA repair genes shape mutational patterns. They take advantage of the Hartwig Medical Foundation (HMF) and TCGA/ICGC databases which have germline and somatic molecular data. These molecular data layers are used as input features for the predictive models of DNA damage response (DDR) gene deficiency.

      Of note, the project is of interest to oncology in the sense of unveiling new genes to be further investigated as a therapeutic candidate target in cancer.

      This paper brings statistical modelling based on LASSO regression coupled with appropriate metrics for unbalanced data sets. Their finds recapitulate known DDR-associate genes but novel genes that can be explored in animal models or functional assays with cell lines.

    1. Reviewer #2 (Public Review):

      The paper describes the participation in CRC screening in Denmark and compliance to colonoscopy in FIT positive screened people during pandemic.

      There are interesting data, particularly in the breakdown by age socioeconomic status and immigrant status. Nevertheless, the study remains very descriptive. When a pandemic occurs and different strategies are put in place in different countries to afford this emergency, probably we also need simple descriptions of what happened, considering anything as a natural experiment to be reported. Furthermore, Denmark is one of the few (or the only) European countries that did not stop CRC screening even during the lockdown. Thus it is worth documenting what happened, with a scientific paper. The consequence is that the paper is not very gripping.

      The paper is very well written and the report is rigorous, the methods well documented, tables and figure clear.

    1. Reviewer #2 (Public Review):

      Previous studies have shown that lhx1 progenitors proliferate upon AKI in adult zebrafish mesonephros. However, these studies have focused primarily on renal progenitor cells (RPCs). This study uses single-cell mRNA sequencing to identify a novel cell type (RICs) in the zebrafish mesonephros that is marked by fabp10a expression within a previously generated GFP transgenic zebrafish line. The authors show that RICs express cox2 to synthesize PGE2 upon gentamicin-mediated AKI, which correlates with PRC proliferation. They demonstrate that PGE2 stimulates RPC proliferation through EP4b receptor activation of PKA, which in turn stabilizes beta-catenin through phosphorylation of both beta-catenin and GSK3beta. They also indicate that beta-catenin stabilization and RPC proliferation is dependent upon wnt4 expression by the RPC itself. The topic of the paper is significant in that it identifies an interstitial in the zebrafish kidney and suggests several mechanisms by which it supports nephron regeneration.

    1. Reviewer #2 (Public Review):

      Tan et al. have used state-of-the-art methodology (mouse genetics, superresolution microscopy and synaptic electrophysiology) to further delineate the role of Munc13 proteins by investigating their function within a scenario in which the presynaptic active zone is deprived of major protein scaffolds. The authors have transduced Cre-expressing lentiviruses into hippocampal neuronal cultures from mice with floxed alleles to remove six fundamental components of the presynaptic active zone: RIM1, RIM2, ELKS1, ELKS2, Munc13-1, Munc13-2 and Munc13-3. The first part of the study comprises a comparison between neurons lacking RIM1, RIM2, ELKS1, ELKS2, on one side, and neurons lacking Munc13-1 and Munc13-2 on the other. Within the first group of neurons the levels of Munc13-1 at the nerve terminals are already reduced (assessed by confocal and STED microscopy and western blots) and the residual amount left is located far away from the active zone. Remarkably synapse formation occurs normally upon the hextuple knock-out of active zone proteins, however, vesicle docking is disrupted and single-action potential evoked and spontaneous release is reduced at glutamatergic and GABAergic synapses. A key finding is that the single-action potential evoked release still detected in the RIM/ELS cuadruple knock-out is almost completely abolished upon the additional knock-out of Munc13-1 and Munc13-2. This is a major observation of the study that support, as the authors concluded, that Munc13 promotes the fusogenicity of synaptic vesicles even when Munc13 is not properly located at the active zone. Careful electrophysiological measurements show that in the absence of Munc13 the size of the readily releasable pool (RRP) of synaptic vesicles is further reduced without specific changes in the vesicular release probability. Overall, the electrophysiological data support well the notion that Munc13 is specifically responsible for the remaining RRP and therefore reinforce the notion that Munc13 acts at the priming stage and can do it in part independently of RIMs and ELSs. Importantly, the results further support the notion that synapse formation is a remarkably resilient process that occurs even under strong perturbation of presynaptic function.

      As a secondary conclusion, the authors point out that postsynaptic response is intact, this specific point should be further discussed and analyzed.

      The study is very clearly written and presents very relevant findings of interest for readers in the field of the molecular mechanisms of synaptic operation.

    1. Reviewer #2 (Public Review):

      In this article, Iyer et al discuss the mechanics of reprogramming challenges encountered by supporting cells towards their potential pathway of dedifferentiating into hair cell types. Previous literature has shown the ability of ATOH-1, GFl-1, and POU4F3 to transform supporting cells into hair-like cell types. Here authors suggest that the combinatorial expression of these TFs can enhance the efficiency of the transcriptional remodeling of supporting cells to initiate the reprogramming toward hair-like cell lineage. It is a well-conducted study. Please see my comments/concerns below.

      1. In the representative images, the effect of GFl-1 seems to be less efficient or has no effect on reprogramming the lineage of supporting cells to hair cell-like cells in comparison to two other groups ATOH-1 alone or ATOH-1, GFl-1, and Pou4F3 combined (Figure 1, 1- S2, 2B, 4A) and even the single-cell RNA seq can be interpreted similarly (Figure 3C, 6C. According to authors and previous literature, GFl1 is supposed to be acting in concert to enhance the efficiency of this lineage conversion at least in older animals. The representative images and single-cell UMAPs show that either GFl-1 is not efficient or less efficient than ATOH-1 alone or ATOH-1, GFl-1, and Pou4F3 combined. Hence, why authors chose not to explore ATOH-1 and Pou4F3 without GFl-1.

      2. In Figure 3C, the authors find the most reduction in cell numbers in lateral GER during transcriptional reprogramming. Can authors comment on why the cells in this region are more susceptible to lineage reprogramming into hair cell-like cells?

      3. In figure 5A, how can the existing hair cells be distinguished from newly formed hair cell-like cells.

      4. Authors cited previous literature showing that existing hair cells can affect lineage reprogramming of supporting cells through Notch signaling. So would it not be a better experimental design when the hair cells were depleted prior to transcriptional reprogramming.

      5. Genetic mutations that lead to functional disruptions in supporting cells are also linked to hearing loss. Can authors predict how feasible would be the idea of in vivo conversion of one important cell type to another important cell type?

      6. Are reprogrammed hair cell-like cells transcriptionally similar to outer hair cells, inner hair cells, or none?

    1. Reviewer #2 (Public Review):

      The manuscript entitled "Fixation Can Change the Appearance of Phase Separation in Living Cells" discussed the different fixation artefacts that can change the appearance of LLPS. The manuscript points out a fundamental question in the field of phase separation which is rarely discussed. The authors found that PFA fixation can both enhance and diminish putative LLPS behaviors; in some cases, it can also create condensates that did not exist in living cells. Using a simple but elegant model, they found that protein localization in fixed cells depends on an intricate balance of protein-protein interaction dynamics, the overall rate of fixation, and notably, the difference between fixation rates of different proteins. They conclude that less dynamic interactions are better captured by PFA fixation. The text is clearly written, the experiments are well designed and the simulations give an interesting explanation of the different artefacts observed after fixation.

      To describe LLPS or to distinguish between polymer-polymer phase separation and LLPS, recent studies have used single particle tracking, a technique allowing to follow the dynamics of individual proteins in living cells (https://doi.org/10.7554/eLife.60577; https://doi.org/10.7554/eLife.69181; https://doi.org/10.7554/eLife.47098). The authors should mention that such an approach can be a good alternative to avoid the artefact of fixation.<br /> Using techniques such as single particle tracking or FCS, it is possible to estimate the effective diffusion coefficient of protein-living cells. When a liquid phase separation is formed, it is also possible to estimate the diffusion coefficient of the protein of interest (POI) inside versus outside of the LLPS. The authors say that less dynamic interactions are better captured by PFA fixation. In the simulation part, would it be possible to predict from the diffusion coefficients of the POI inside a condensate the effect of the PAF fixation?

      Finally, the authors propose that in the future, it will be important to design novel fixatives with significantly faster cross-linking rates than biomolecular interactions to eliminate fixation artifacts in the cell. It would be even more interesting if the authors could propose some ideas of potential novel fixatives. Did they test several concentrations of PFA, for example? Did they test different times of PFA incubation? Did they test cryofixation and do they know what would be their effect on LLPS? Do they have novel fixatives in mind?

      Adding some precisions about these points in the simulation and in the fixation protocol would increase the impact of the manuscript. Otherwise, the study is interesting and thought-provoking.

    1. Reviewer #2 (Public Review):

      This paper reports the results of optical imaging experiments on areas V4, V2, and V1 in anesthetised macaque monkeys. The experiments were designed to reveal details of the representation of spatial frequency (SF), orientation (OR), and color in these areas. Evidence for gradients of SF selectivity across the areas is presented. It is also shown that SF and OR maps in V2 and V4 have iso-parameter contours that intersect at right angles, in agreement with, and extending, observations made in V1 and visual areas in cats and other species. Color domains tend to be located in low-SF domains and avoid the higher SF regions. Relationships between V2 stripes and SF preference are also established.

      These findings are a potentially valuable contribution to understanding the maps that exist in V4, which have received less attention than those in areas V1 and V2. However, I have some serious concerns about the validity of the results.

    1. Reviewer #2 (Public Review):

      Auwerx et al. present a framework for the integration of results from expression quantitative trait loci (eQTL), metabolite QTL (mQTL) and genome-wide association (GWA) studies based on the use of summary statistics and Mendelian Randomization (MR). The aim of their study is to provide the field with a method that allows for the detection of causal relationships between transcript levels and phenotypes by integrating information about the effect of transcripts on metabolites and the downstream effect of these metabolites on phenotypes reported by GWA studies. The method requires the mapping of identical SNPs in disconnected mQTL and eQTL studies, which allows MR-based inference of a causal effect from a transcript to a metabolite. The effect of both transcripts and metabolites on phenotypes is evaluated in the same MR-based manner by overlaying eQTL and mQTL SNPs with SNPs present in phenotypic GWA studies.

      The aim of the presented approach is two-fold: (1) to allow identification of additional causal relationships between transcript levels and phenotypes as compared to an approach limited to the evaluation of transcript-to-phenotype associations (transcriptome-wide MR, TWMR) and (2) to provide information about the mechanism of effects originating from causally linked transcripts via the metabolite layer to a phenotype.

      The study is presented in a very clear and concise way. In the part based on empirical study results, the approach leads to the identification of a set of potential causal triplets between transcripts, metabolites and phenotypes. Several examples of such causal links are presented, which are in agreement with literature but also contain testable hypotheses about novel functional relationships. The simulation study is well documented and addresses an important question pertaining to the approach taken: Does the integration of mQTL data at the level of a mediator allow for higher power to detect causal transcript to phenotype associations?

      Major Concerns<br /> 1. Our most salient concern regarding the presented approach is the presence of multiple testing problems. In the analysis of empirical datasets (p. 4), the rational for setting FDR thresholds is not clearly stated. While this appears to be a Bonferroni-type correction (p-value threshold divided by number of transcripts or metabolites tested), the thresholds do not reflect the actual number of tests performed (7883 transcripts times 453 metabolites for transcript-metabolite associations, 87 metabolites or 10435 transcripts times 28 complex phenotypes). The correct and more stringent thresholds certainly decrease the overlap between causal relationships and thus reduce the identifiable number of causal triplets. Furthermore, we believe that multiple testing has to be considered for correct interpretation of the power analysis. The study compares the power of a TWMR-only approach to the power of mediation-based MR by comparing "power(TP)" against "power(TM) * power(MP)" (p. 12). This comparison is useful in a hypothetical situation given data on a single transcript affecting a single phenotype, and with potential mediation via a single metabolite. However, in an actual empirical situation, the number of non-causal transcript-metabolite-phenotype triplets will exceed the number of non-causal transcript-phenotype associations due to the multiplication with the number of metabolites that have to be evaluated. This creates a tremendous burden of multiple testing, which will very likely outweigh the increase in power afforded by the mediation-based approach in the hypothetical "single transcript-metabolite-phenotype" situation described here. Thus, for explorative detection of causal transcript-phenotype relationships, the TWMR-only method might even outperform the mediation-based method described by the authors, simply because the former requires a smaller number of hypotheses to be tested compared to the latter. The presented simulation would only hold in cases where a single path of causality with a known potential mediator is to be tested.

      2. A second concern regards the interpretation of the results based on the empirical datasets. For the identified 206 transcript-metabolite-phenotype causal triplets, the authors show a comparison between TWMR-based total effect of transcripts on phenotypes and the calculated direct effect based on a multivariable MR (MVMR) test (Figure 2B), which corrects for the indirect effect mediated by the metabolite in the causal triplet. The comparison shows a strong correlation between direct and total effect. A thorough discussion of the potential reasons for deviation (in both negative and positive directions) from the identity line is missing. Furthermore, no test of significance for potential cases of mediation is presented. Due to the issues of multiple testing discussed above, the significance of the inferred cases of mediation is drawn into question. The examples presented for causal triplets (involving the ANKH and SLC6A12 transcripts) feature transcripts with low total effects and a small ratio between direct and total effect, in line with the power analysis. However, in these examples, the total effects are also quite low. Its significance has to be tested with an appropriate statistical test, incorporating multiple testing correction. Furthermore, the analysis of the empirical data indicates that the ratio between direct and indirect effect of a transcript on a phenotype is in most cases close to identity, except for triplets with low total effects. This fact should be considered in the power analysis, which assigned the highest gain in power by the mediation analysis to cases of low direct to total effect ratio. The empirical data indicate that these cases might be rare or of minor relevance for the tested phenotypes.

      3. Related to the interpretation of causal links: horizontal pleiotropy needs to be considered. The authors report the identification of causal links between TMEM258, FADS1 and FADS2, arachidonic acid-derived lipids and complex phenotypes. However, they also mention the high degree of pleiotropy due to linkage disequilibrium at the underlying eQTL and mQTL region as well as the network of over 50 complex lipids known to be associated with the expression of the above transcripts. Thus, it seems possible that the levels of undetected lipid species may be more important for the phenotypic effect of variation in these transcripts and that the reported "mediators" are rather covariates. Such horizontal pleiotropy would violate a basic assumption of the MR approach. While we think that this does not invalidate the approach altogether, it does affect the interpretation of specific metabolites as mediators. This is aggravated by the fact that metabolic networks are more tightly interconnected than macromolecular interaction networks (assortative nature of metabolic networks) and that single point-measurements of metabolites may not be generally informative about the flux through a specific metabolic pathway.

    1. Reviewer #2 (Public Review):

      In the manuscript, Mijnheer et al mainly exploited CyTOF Helios mass cytometer and TCRβ repertoire sequencing to investigate the T cell composition and distribution in peripheral blood and synovial fluid, and further explored the temporal and spatial dynamics of regulatory T cells (Tregs) and non-Tregs in the inflamed joints of Juvenile Idiopathic Arthritis (JIA) patients. Their results indicate that the activated effector T cells and hyper-expanded Treg TCRβ clones found at the inflamed joints are highly persistent in the circulation, and the dominant of high degree of sequence similarity of Treg clones could serve as the novel therapeutic targets for the JIA treatment. Overall, the research design is appropriate, and the methods are adequately described in the study. However, several issues are required to be addressed.

      (1) The criteria for the JIA patient's recruitment should be clearly presented in the method section. For example, what is the specific included criteria and excluded criteria? Or did the patients take medicines for the treatment during the study?<br /> (2) As for the correlation analysis of the entire spectrum of node frequencies, the SFMCs and PBMCs isolated from 3 patients were conducted in the study. The sample size is too limited to obtain robust results and to make a convincing conclusion from the correlation analysis. And it is shown that a total of 9 JIA patients have been involved in the study. Could the author clarify it?<br /> (3) The results of the study indicate that the hyper-expanded T cell clones are shared between left and right knee joints. Since JIA may affect one or more joints, did the author check other joints to see if the same expanded T cell clones infiltrate multiple joints, such as hand or wrist?<br /> (4) For Fig.2B, the Treg CD25+FOXP3+ population was significantly enriched in synovial fluid (SF). Is it from the left knee joints or the right knee joints?<br /> And in the context of Line 144-148, it indicated the SF, however, the title of axis in Fig.2B indicated Synovial Fluid Mononuclear Cells (SFMCs). Please keep consistent.<br /> (5) For the longitudinal sampling timelines of JIA patients shown in Supplementary Fig.3, the interval of PB and SF sample collection is not consistent. And only 1 patient completed 4 visits and the sample collection. It is hard to make any conclusion from 1 patient.

    1. Reviewer #2 (Public Review):

      The current treatment for the radical cure of Plasmodium vivax malaria is primaquine, it was first made available in the 1950s and there is a need for better treatments. Recently a new drug was licensed, tafenoquine. Tafenoquine is a single-dose treatment due to the drug's long half-life. The expected increase in treatment adherence is an important advantage, however, the drug's slow elimination has also a drawback. Patients must be tested for a ubiquitous enzyme (glucose-6-phosphate dehydrogenase) deficiency prior to treatment, as the use of this drug in the G6DP deficient population could lead to life-threatening haemolysis. Implementing accurate quantitative testing in remote malaria-endemic areas is challenging. Providing point-of-care test equipment, supplies and training may not be cost-effective as the efficacy of tafenoquine has not been proven non-inferior to primaquine.

      Thus strategies to increase tafenoquine efficacy are of paramount importance to raise the public health relevance of the first new drug developed for the radical cure of vivax malaria in the last 70 years. This paper polled together and analysed the clinical information of participants of the tafenoquine clinical trials, and using models they evaluated the influence of dose per weight on the recurrence rate of the disease. They predict that the tafenoquine efficacy would surpass the primaquine one if the tafenoquine dose was increased. They also correlated the levels of methaemoglobin production and the reduction of relapses, implying that methaemoglobin can be a surrogate marker of efficacy.

      As with any model prediction, these results should be confirmed in clinical trials, especially the safety profile of the suggested regimen. The surrogate marker of oxidative drug activity is a very interesting indirect efficacy measurement, although it is limited to any indirect outcome. Even the vivax recurrence rate itself has limitations as vivax relapse and reinfection cannot be differentiated. Still, these results provide a solid support for future clinical trials that might reinforce the public health relevance of tafenoquine.

    1. Reviewer #2 (Public Review):

      In this manuscript, the authors use tandem mass spectrometry to identify peptides from the eggshell protein struthiocalcin-1 preserved in a fossilized eggshell ~6.5 Ma years old. They report multiple peptide spectral matches (peptide identifications) to a small section of the struthiocalcin-1 protein. The high-resolution, well-annotated spectral matches provided by the authors show that that region of struthiocalcin-1 may be preferentially preserved in ancient ostrich shell tissue.

      These findings are important because Cenozoic tissues greater than 1 Ma in age are drastically unexplored in terms of protein preservation. Thus, these data represent a big step forward in the investigation of proteomic preservation throughout the Cenozoic.

    1. Reviewer #2 (Public Review):

      The authors report a series of genetic experiments that allow for the rigorous evaluation of the role of pre-synaptic contact and activity on dendrite morphogenesis and/or stabilization between a model pair of connected sensory and interneurons in the Drosophila larval CNS. Experiments to mis-position the presynaptic arbors of the DBD neuron reveal contact-dependent effects on post-synaptic dendrite growth. Ablation, silencing and activation experiments support the interesting model that neuronal activity in the sensory afferents act to globally constrain post-synaptic dendrite growth. Thus, coordination of presynaptic contact and activity act in opposition to sculpt post-synaptic dendrites. One weakness/limitation of the study is the inability of the authors to evaluate whether the observed effects are due to changes in the initiation of dendrite growth as opposed to maintenance or stabilization effects. The authors adequately acknowledge and discuss this limitation. Overall, this is a beautifully conducted study that adds new insights into synaptic partner matching.

    1. Privatisation can cause serious problems, even in developing countries, due to a lack in institutional development and to corruption.

      Because of poor institutional development and excessive corruption, privatization causes serious problems

    2. Simply converting a public sector monopoly to a private one is not a solution, especially if the profit is only in the water supply of large municipal areas and then is of interest to a TNC not present in the irrigation or water supply of dense populated areas.

      Claim 2: Water distribution is a business not a human right Evidence f/ Claim 2: The privatization of water sources is in the pursuit of profits and not distribution

    1. Reviewer #2 (Public Review):

      The study included all women aged 23-64 years invited for cervical cancer screening in Denmark in 2015-2021 (n=2,220,00). The Danish registries provide an ideal setting for the study. Classification of explanatory covariates followed Danish and international standards. The authors estimated the prevalence ratios using a generalised linear model with a log link for the Poisson family. Material and statistical methods are appropriate for the study's aims.

      As the authors write, several studies have demonstrated lower participation among immigrants and women with lower socioeconomic status. However, the authors wanted to evaluate whether divergence may have been exacerbated during the pandemic. Unfortunately, they do not provide any justification for why they would hypothesize that to happen.

      The authors write that women who unregistered from the screening programme within 1 year since invitation (n=56,920) were excluded. If those who are at higher risk of cancer and with lower participation rates unregister themselves, the compliance to screening could be overestimated.

      The authors find that some age groups i.e. women aged 40-49 and those aged 60-64 years had a lower participation rate and conclude that it could indicate that the restrictions within a society affect different age groups disproportionally. The authors do not try to explain the finding and it should be scrutinized to rule out a chance. Comorbidity is strongly associated with age so if this is attributed to self-isolation, there should be a gradient. Why 50-59 years old would be different from 60-64 years?

      In general, study results support the conclusions. The authors consider the inconsistent health messages as a reason for women not to participate. What about fear? In several countries, there was a clear decrease in emergency admissions to the hospital which suggest that people were avoiding hospital because they were nervous about catching COVID-19.

    1. Reviewer #2 (Public Review):

      The present manuscript provides a mechanistic explanation for an event in adrenal endocrinology: the resistance which develops during excessive inflammation relative to acute inflammation. The authors identify disturbances in adrenal mitochondria function that differentiate excessive inflammation. During severe inflammation the TCA in the adrenal is disrupted at the level of succinate production producing an accumulation of succinate in the adrenal cortex. The authors also provide a mechanistic explanation for the accumulation of succinate, they demonstrate that IL1b decreases expression of SDH the enzyme that degrades succinate through a methylation event in the SDH promoter. This work presents a solid explanation for an important phenomenon. Below are a few questions that should be resolved experimentally.

      The authors should confirm through direct biochemical assays of enzymatic activity that steroidogenesis enzyme activity is not impaired. Many of these enzymes are located in the mitochondria and their activity may be diminished due to the disturbed, high succinate environment of the cortical cell as opposed to the low ATP production.

      What is the effect of high ROS production. Is steroidogenesis resolved if ROS is pharmacologically decreased even if the reduction of ATP is not resolved?

      Does increased intracellular succinate (through cell permeable succinate treatment) inhibit steroidogenesis even if there is not a blockage of OXPHOS?

      It should be demonstrated the genetic loss of IL1 signaling in adrenal cortical cells results in a loss of the effect of LPS on reduced steroidogenesis and increased succinate accumulation.

      It should be demonstrated the genetic loss of IL1 signaling in adrenal cortical cells results in a loss of the effect of LPS on SDH activity and ATP production and SDH promoter methylation

      It should be shown that the silencing of DNMT eliminates or diminishes the effect of LPS on reduced steroidogenesis and increased succinate accumulation.

      Does silencing of DNMT reduce OXPHOS in adrenal cortical cells?

      The effects of LPS on reduced adrenal steroidogenesis are not elaborated at the physiological level. The manuscript should demonstrate the ramifications of the adrenal function decreasing after LPS. Does CORT release become less pronounced after subsequent challenges? Does baseline CORT decrease at some point? No physiological consequences are shown. Similarly, these physiological consequences of decreased adrenal function should be dependent on decreased SDH activity and OXPHOS in adrenal cells and this should be demonstrated experimentally.

    1. Reviewer #2 (Public Review):

      The authors use the phylogeny of SARS-CoV-2 to find signals of functional interactions among the evolving amino acids of the spike protein. They do this by looking for pairs of substitutions that either tend to appear consecutively on branches, indicating positive interactions, or to appear on separate branches, indicating negative interactions. Although a massive number of SARS-CoV-2 sequences have been collected, many of these sequences have errors in them or are similar to each other. This affects the accuracy of the reconstructed phylogeny and the placement of mutations on it, creating difficulties for this approach. Still, the authors are able to identify several sets of sites with clear signals of interaction, and where the interaction makes sense given the structure of the protein. Some of these sites are carried by the Omicron variant, indicating that positive epistasis likely played a role in its evolution.

    1. Reviewer #2 (Public Review):

      The authors examined the neural activity of the ventral hippocampus (vH) during exploration of anxiogenic environments. They first recorded vH neuronal activity when animals explored the elevated plus maze (EPM). Although they observed that peak firing activity increased when rats explored anxiogenic locations, this effect was difficult to quantify since rats did not often explore these locations. In order to resolve this issue, they developed a novel type of elevated linear maze (ELM). In the anxiogenic location of the ELM, they observed anxiety-related neuronal activity and demonstrated that the direction-dependent activity of vH neurons became homogenized. Additionally, the authors demonstrated that the activity of the vH neurons reflected and predicted, using a support vector machine (SVM), the exploration of an anxiogenic location, suggesting that vH neurons do not only code for anxiogenic environments, but also may reflect the intention to explore anxiogenic locations.

      Strength:<br /> S1. In their study, the authors introduced a modified ELM task that can instantly reconfigure side walls in the anxiogenic environment while rats are being recorded on the maze. This method was intended to overcome the low-sampling issue observed in the anxiogenic environments where animals usually avoid entering. In fact, this modification allowed them to study between non-anxiogenic and anxiogenic conditions within the same maze and in a single recording session.

      S2. Also, it is known that recording large number of cells from vH has been quite challenging in the field. The authors successfully examined more than 130 neurons from the vH area across six rats and determined remapping effect when animals were exposed to the anxiogenic environment.

      S3. The authors tried to examine the neural population carefully to exclude any other factors to focus solely on the effect of anxiety, although it has been shown that abrupt changes in the environment can cause the hippocampus to remap.

      Weakness:<br /> Despite the fact that the authors are trying to answer potentially important and intriguing questions in the anxiety field, some important details are missing from their description of the data.

      W1. It is remarkable and impactful that the authors found that the vH neurons overrepresent, remap, and lose directionality under anxiogenic conditions. Conceptually, such dramatic changes as well as prospective biased memory 'replays' have been reported in the dorsal hippocampus under anxiogenic task settings, such as using electrical foot shocks, for example, Wu et al, Nat.Neuro, 2017. Also, another paper (Girardeau et al.., 2017, Nat Neuro) reported that an aversive trajectory is more reactivated in the dorsal hippocampus.

      W2. Technically, they used tetrodes in vH and were able to collect more than 130 units, with histological data indicating that recording sites ranged from CA1 to CA3 of vH (Figure 1B). They used a semi-automated clustering method to isolate individual units but did not subdivide them into CA1, CA3 and/or pyramidal cells or interneurons. It appears that the representative examples in Figure 1C contain both pyramidal cells and interneurons, which are well characterized in terms of remapping in the dorsal area.

      W3. Readers may find Figure 5 difficult to follow. They are not intuitive to understand how to read/interpret the figure panels.

    1. Reviewer #2 (Public Review):

      Differences between the infection environment and in vitro model systems likely contribute to disconnects between the antimicrobial susceptibility profile of bacterial isolates and the clinical response of patients. The authors of this paper focus on a specific aspect of the infection environment, the polymicrobial nature of some chronic infections like those in people with Cystic Fibrosis (CF), as a factor that could impact antibiotic tolerance. They first use published genomic datasets and computational techniques to identify a clinically relevant, four-member polymicrobial community composed of Pseudomonas aeruginosa, Staphylococcus aureus, Streptococcus spp., and Prevotella spp. They then develop a high throughput methodology in which this community grows and persists in a CF-like environment and in which antibiotic susceptibility can be tested. The authors determine that living as a member of this community decreases the antibiotic tolerance of some strains of biofilm-associated P. aeruginosa and increases the tolerance of most strains of planktonic and biofilm-associated S. aureus and planktonic and biofilm-associated Streptococcus. They focus on the decreased tolerance of P. aeruginosa and determine that a ΔlasR mutant of P. aeruginosa does not display increased tobramycin susceptibility in the mixed community. One of the phenotypes associated with a ΔlasR mutant is an overproduction of phenazines. The authors find that by deleting the phenazine biosynthesis genes from ΔlasR, they can restore community-acquired susceptibility. They further investigate this phenomenon by showing that a specific type of phenazine, PCA, is significantly increased in mixed communities with the ΔlasR mutant compared to WT. Finally, they demonstrate that adding a specific phenazine, pyocyanin, to mixed communities can restore the tolerance of WT P. aeruginosa.


      With this study the authors address a very important problem in infectious disease microbiology - our in vitro drug susceptibility assays do a poor job of mimicking the infection environment and therefore do a poor job of predicting how effective particular drugs will be for a particular patient. By demonstrating how an infection-relevant community modifies tolerance to a clinically relevant drug, tobramycin, the authors identify specific interactions that could be targeted with therapeutics to improve our ability to treat the chronic infections associated with CF. In addition, this study provides a framework for how to effectively model polymicrobial infections in vitro.

      The experiments in the paper are very rigorous and well-controlled. Statistical analysis is appropriate. The paper is very well-written and clear.

      The authors do an admirable job of using in silico analysis to inform their in vitro studies. Specifically, they provide a comprehensive rationale for why they chose and studied the specific community they did.

      The authors provide a very robust dataset which includes determining how strain differences of each of their four community members affect community dynamics and antibiotic tolerance. These types of analyses are laborious but very important for understanding how broadly applicable any given result is.


      The authors very clearly and convincingly demonstrate that WT P. aeruginosa becomes more susceptible to tobramycin in their mixed community. Our ability to turn these types of observations into therapeutic development depends on mechanistic insight. That said, it is unclear if the authors can make any solid conclusions about what specific aspects of the polymicrobial environment cause WT P. aeruginosa to become more susceptible. The authors make a compelling case that increased phenazine production by the ΔlasR mutant restores tolerance in the mixed community and that exogenous phenazine addition increases the survival of WT P. aeruginosa in the mixed community. However, it remains a plausible explanation that the effects of phenazines on tobramycin susceptibility are independent of the initial observation that WT. P. aeruginosa becomes susceptible to tobramycin in the mixed community.

      Some aspects of the methodology are unclear. Specifically, the authors note that they use a specific sealed container system to grow their strains in anoxic conditions, which mimic portions of CF sputum. However, it is unclear how the authors change medium over the course of their experiments, or how they test susceptibility to tobramycin, without exposing the cells to oxygen. It is well understood that oxygen exposure impacts the susceptibility of P. aeruginosa to tobramycin, so it is very important that the methodology involving oxygen deprivation and exposure is described in detail.

    1. Reviewer #2 (Public Review):

      Millar et al. have used multimodal brain magnetic resonance imaging (MRI) data from subjects with preclinical AD (cognitively normal with amyloid pathology), cognitive impairment, and matched cognitively normal (CN) subjects to predict the subject's age (i.e. brain age). To do so they have trained a Gaussian Process Regression (GPR) model using data from 3 datasets. The predicted age was then compared to the chronological age to calculate the brain age gap (BAG). Using resting-state functional MRI (rsfMRI) they calculated functional connectivity across 300 brain regions. Similarly, T1w MRI images have been used to calculate volumetric measures across 68 cortical and 33 subcortical regions. The results were then used as features in two separate models resulting in FC-BAG and Vol-BAG measures, respectively. A third model is then devised by "stacking" the previous model's predictions as features in a new model resulting in Vol+FC-BAG. The models were then applied to the test dataset and BAG measures were calculated for subjects in CN, preclinical AD, and cognitively impaired (CI) groups. All models show significantly higher BAGs for subjects with cognitive impairments. Finally, the authors have examined the relationship between BAGs measures and Amyloid Markers, Tau Markers, Neurodegeneration Markers, and Cognition.


      The manuscript is very clearly written. The study is well designed and for the most parts the method section contains all the necessary information to replicate the steps. The sample size is comparable to similar studies investigating brain age in clinical populations and the inclusion and exclusion criteria are clearly stated. In order to avoid bias and overfitting in the predictive models the authors have (1) used a separate training (+validation) set and test set and (2) removed any subjects with potential pathology or impairment from the training set. Using data points on the plots as well as a combination of boxplot+violin plots makes the results clear and data distributions are provided when necessary. Furthermore, chronological age has been used as a covariate to correct the relationship between BAG and age, making the results more interpretable and reliable. Focusing on the stronger section of the results, the study shows a higher Vol-BAG (or Vol+FC-BAG) in subjects with CI, which is significantly related to higher Amyloid PET, higher PET and CSF-related Tau measures, and lower global cognition. In conclusion, the Vol-BAG results are clear and clinically relevant, based on a model with a reasonable prediction performance.


      The manuscript follows authors' recently published work on FC-BAG in symptomatic and preclinical Alzheimer disease (Millar et al, Neuroimage 2022) by adding T1w volumetric measures from Freesurfer. Based on the results the additional value of rsfMRI connectivity is at best marginal. The FC-BAG model has a weak performance and is outperformed by Vol-BAG. The marginal benefit of adding FC-BAG to the Vol-BAG model is around 10% which comes with the additional cost of a new and more computationally demanding modality as well as making the biological relevance of the model almost untraceable. The preclinical findings reported as "Specifically, FC-BAG may capture a unique biphasic response to preclinical AD pathology" while potentially interesting are based on an unreliable model (FC-BAG) and can be a spurious finding. These results need further validation both robustness analysis within the current sample and in independent datasets. The other findings related to preclinical AD are based on the hippocampal volume which as the authors have mentioned in the discussion limitation is part of the features included in the Vol-BAG model and absent from FC-BAG.

      In conclusion, the manuscript has clear findings based on the Vol-BAG model differentiating the cognitively impaired subjects from other groups and these results relate to the clinical severity of the disease as measured by Amyloid Markers, Tau Markers, and Cognition.

    1. Reviewer #2 (Public Review):

      Here the authors used viral expression and two-photon imaging, a very demanding approach, to explore the transport dynamics of three membrane markers (Neuropeptide Y-dense core vesicles, LAMP1-endolysosomes and RAB7-late endosomes) in vivo in the mouse brain. This allowed deciphering for the first time anterograde and retrograde velocities in vivo rather than in cultured neurons. The authors showed that the different vesicular compartments have different anterograde and retrograde velocities, pausing at synapses. They further used brain slices to explore the effect of increased calcium levels.

      Major strengths reside in the novelty of the approach (in vivo!).

      The main weakness relates to the lack of novel mechanisms and the difficulty of using such a sophisticated setup on a routine basis.

      This is a technical 'tour-de-force', a clear reference article for future studies addressing vesicular transport in vivo.

      Of course, one would be curious to see many more markers studied in this setup. Also, the same study in mouse mutants would be extremely interesting.

    1. Reviewer #2 (Public Review):

      Hebart et al., present a large-scale multi-model dataset consisting of fMRI, EEG, and behavioral similarity measures towards the study of object representation in the mind and brain. The effort is immense, the methods are rigorous, and the data are of reasonable quality, the demonstrative analyses are extensive and provocative. (One small note regarding one leg of this multi-modal dataset is that the fMRI design consisted of a single image presentation for 0.5s without repetitions for most of the images; this design choice has particular analysis implications, e.g. the dataset will have more power when leveraging a priori grouping of images. However, unlike other datasets of this kind, here the number of images and how they were selected does support this analysis mode, e.g. multiple exemplars per object concept, and rich accompanying meta-data and behavioral data.)

      The manuscript is well-written, and the THINGs website that lets you explore the datasets is easy to navigate, delivering on the promise of making this an integrated, expanding worldwide initiative. Further, the datasets have clear complementary strengths to recent other large-scale datasets, in terms of the ways that the images were sampled (not to mention being multi-modal)-thus I suspect that the THINGs dataset will be heavily used by the cognitive/computational/neuroscience research community going forward.

    1. Reviewer #2 (Public Review):

      I found the study and findings important and largely convincing. While some of these observations might continue to refine with further sampling, the value of these data for what they already are, the novelty in the comparison, and the strength and importance of these results for our understanding of deep-sea marine ecosystems and variation thereof, are all exemplary.

      My primary critique is the near-absence of statistical analyses in the current version of the manuscript that are necessary to support the many descriptive observations made with a more formal hypothesis testing framework, as well. Developing an appropriate framework for such analyses throughout the paper, including consideration of the multiple tests that will be performed. This is important for many reasons, including by providing a more formal sense of uncertainty in the conclusions to readers, given the understandable sampling limitations. Planning and conducting these analyses will require considerable work.

    1. Reviewer #2 (Public Review):

      This manuscript builds on previous work from the Pearson lab showing that one aspect of the trisomy 21 phenotype could be caused by an increase in the amount of pericentrin (PCNT), a component of the centrosome. The earlier work showed that the increase in PCNT is sufficient to reduce the frequency of ciliation in trisomy 21 cells and that the increased PCNT is often in the form of protein aggregates along microtubules proximal to the centrosome (in a preprint). Here they use several models with 3 or 4 copies of human chromosome 21 or the mouse equivalent to examine the defect in cilium formation at the level of specific proteins and the signaling function of the cilium. This is a substantial contribution that furthers the evidence for the authors' favored model of excess PCNT causing some form of pericentrosomal crowding that hinders the ability of other molecules, complexes, and/or vesicles to get to the right place at the right time. The work makes excellent use of cell lines and mice previously generated for the study of trisomy 21, making for well-controlled experiments in a situation where this is particularly important (only 1.5 x increased expression). One does wish that it were possible to do the PCNT depletion in more of the experiments than the single one shown, but that is understandable given the amount of work required and the uncertainty associated with RNAi depletion.

    1. Reviewer #2 (Public Review):

      Here, McKay, et al. describe a new automated system to feed killifish, and use it to explore dietary restriction effects on killifish lifespan and to develop an associative learning assay, two important goals in the KF/longevity field.

      Fig. 1-2- The first figures focus on the design and evaluation of the feeding system. It appears that the feeding system works well and achieves what the authors set out to do.<br /> Fig. 3 explains the DR and overfeeding setup, and effects on growth and reproduction; demonstrates that the automated feeding system does achieve DR.<br /> Fig. 4 explains the DR setup and results on male and female KF, highlighting the fact that DR only extends the lifespan of males. This sex-specific effect seems somewhat surprising, and warrants further follow-up studies.<br /> Fig. 5 describes the associative learning assay, which is based on the ability of the fish to sense a red light and learn that it is associated with feeding. It is great that the authors have been able to develop a learning assay, which will no doubt become an important tool in the killifish researcher's arsenal, but additional experiments are necessary to increase the general impact of the work.

      Overall, while the results seem sound, the current version of the manuscript may be pitched to a small audience (killifish researchers) who will benefit from the development of this methodology. Perhaps the paper could be re-structured to focus less on the methodology and more on the results, fleshing out the associative learning results even more (are there mutants that extend the length of associative learning? Does it require conserved genes? etc). Further exploration of the sex-specific effects of DR on lifespan (why does this only affect males) would also raise the general interest of the work, but both the DR and associative learning aspects of the paper would need to be studied quite a bit more to move this beyond a methods paper.

    1. Reviewer #2 (Public Review):

      In the current manuscript, Feng et al. investigate the mechanisms used by acute leukemia to get an advantage for the access to the hematopoietic niches at the expense of normal hematopoietic cells. They propose that B-ALLs hijack the niche by inducing the downmodulation of IL7 and CXCL12 by stimulating LepR+ MSCs through LTab/LTbR signaling. In order to prove the importance of LTab expression in B-ALL growth, they block LTab/LTbR signaling either through ligand/receptor inactivation or by using a LTbR-Ig decoy. They also show that CXCL12 and the DNA damage response induce LTab expression by B-ALL. They finally propose that similar mechanisms also favor the growth of acute myeloid leukemia.

      Although the proposed mechanism is of particular interest, further experiments and controls are needed to strongly support the conclusions.

      1/ Globally, statistics have to be revised. The authors have to include a "statistical analysis" section in the Material and Methods to explain how they proceeded and specify for each panel in the figure legend which tests they used according to the general rules of statistics.

      2/ The setup of each experiment is confusing and needs to be detailed. Cell numbers are not coherent from one experiment to the other. As an example, there are discrepancies between Fig1 and Fig2. Based on the setup of the experiment in Fig.2 (Injection of B-ALL to mice followed by 2 injections of treatment every 5 days), mice have probably been sacrificed 12-14 days post leukemic cell injection. However, according to Fig.1, B cells and erythroid cells at this time point should be decreased >10 times while they are only decreased 2-4 times in Fig.2. This is also the case in Fig.4B-J or Fig.5D with even a lower decrease in B cells and erythroid cells despite a high number of leukemic cells. Please explain and give the end point for each experiment in each figure (main and supplemental).

      3/ To formally prove that the observed effect is really due to LTab/LTbR signaling, the authors must perform further control experiments. LTbR signaling is better known for its positive role on lymphocyte migration. They cannot rule out by blocking LTbR signaling, that they inhibit homing of leukemic cells into the bone marrow through a systemic/peripheral effect, more than through an impaired crosstalk with BM LepR+ cells. They must confirm for inhibited/deficient LTbR signaling conditions, as compared to control, that similar B-ALL numbers home to the BM parenchyma at an early time point after injection. Furthermore, they cannot exclude that the effect on the expression of IL7 (and other genes), and consequently the effect on B cell numbers, is not simply due to the tumor burden. Indeed, B-ALL numbers/frequencies are different between control and inhibited/deficient signaling conditions at the time of analysis. The analyses should thus be performed at similar low and high tumor burden in the BM for both control and inhibited/deficient LTbR signaling conditions.

      4/ LT/LTbR signaling is particularly known for its capacity to stimulate Cxcl12 expression. How do the authors explain that they see the opposite?

      5/ The authors show that CXCL12 stimulates LTa expression in their cell line. They then propose that CXCR4 signaling in leukemic cells potentiates ALL lethality by showing that a CXCR4 antagonist reverses the decrease in IL7 and improves survival of the mice. This experiment is difficult to interpret. CXCL12 has been shown to be important for migration/retention of B-ALL in the BM and the decreased tumor burden is probably linked to a decreased migration more than an impaired crosstalk with LepR+ cells (see also point 3). If CXCL12 increases LTab expression, CXCR4 blockade should do the opposite. This result should be presented. The contradiction is that if B-ALLs induce a decrease in CXCL12 in the BM (in addition to IL7) and that CXCL12 regulates LTab levels, leukemic cells should be exhausted. Similarly, IL7 has been previously shown to stimulate LTab expression and B-ALL cells express the IL7R. Again, a decrease in IL7 should be unfavorable to B-ALL. How do they explain these discrepancies?

      6/ In Supp 4A, RAG-/- mice are blocked at the pro-B cell stage and do not have pre-B cells. Please compare LTa and LTb expression by Artemis deficient pre-B cell to wt pre-B cells. In this experiment, the authors show that similarly to B-ALL artemis-/- pre-leukemic pre-B cells express high levels of LTab and induce IL7 downmodulation. Using mice deficient for LTbR in LepR+ cells, they show that IL7 expression is increased. However, in opposition to leukemic cells (see Figure 4F), pre-leukemic cells are increased in absence of LTab/LTbR signaling. Please explain this discrepancy. The authors use only one B-ALL model cell line for their demonstration (BCR-ABL expressing B-ALL). Another model should be used to confirm whether LTab/LTbR signaling does favor leukemic/pre-leukemic B cell growth.

      7/ Pre-B cells are composed of large pre-B cells (pre-BCR+) and small pre-B cells (pre-BCR-). BCR-ABL B-ALL cells express the pre-BCR. What is the level of expression of LTa and LTb by each of these 2 subsets as compared to BCR-ABL B-ALL?

    1. Reviewer #2 (Public Review):

      This modeling paper looks at how single spikes in the cortex are able to evoke patterns of sequential neural response in the surrounding neural network, an effect observed in the visual cortex of turtles, rodents, and the middle temporal cortex of humans, and possibly generalizable across many other species and brain areas. The results are anchored by population recordings from the turtle cortex, recapitulating those data and exploring how single spikes might be able to have such an outsized effect on broad-scale neural activity. The authors aim to show which kinds of network connectivity support this kind of response.

      The results reveal that sparse, but strong connections in a neural network are the necessary ingredient for the reliable triggering of network sequences by single spikes. Dense, but weaker networks can give rise to different sequences when triggered. One of the most intriguing results of the paper is the interaction of sequences triggered by different single spikes that are part of a strong, sparse sub-network. These concurrent sequences appear to be separable and potentially supported a wide repertoire of response states to very targeted and combinatorially expressive inputs.

      The work is careful and well-executed and the work will be of interest to systems and computational neuroscientists. In particular, the work speaks to how to reliably trigger a wide array of broad-scale population sequence patterns. This could be important for signaling salient, complex external stimuli, especially in a dynamic environment. The work will also be of interest to the machine learning community working on recurrent neural networks and their computational capacity.

    1. Reviewer #2 (Public Review):

      Grasses develop morphologically unique stomata for efficient gas exchange. A key feature of stomata is the subsidiary cell (SC), which laterally flanks the guard cell (GC). Although it has been shown that the lateral SC contributes to rapid stomatal opening and closing, little is known about how the SC is generated from the subsidiary mother cell (SMC) and how the SMC acquires its intracellular polarity. The authors identified BdPOLAR as a polarity factor that forms a polarity domain in the SMC in a BdPAN1-dependent manner. They concluded that BdPAN1 and BdPOLAR exhibit mutually exclusive localization patterns within SMCs and that formative SC division requires both. Further mutant analysis showed that BdPAN1 and BdPOLAR act in SMC nuclear migration and the proper placement of the cortical division site marker BdTANGLED1, respectively. This study reveals a unique developmental process of grass stomata, where two opposing polarity factors form domains in the SMC and ensure asymmetric cell division and SC generation.

      The findings of this study, if further validated, are novel and interesting. However, I feel that the data presented in the current manuscript do not fully support some crucial conclusions. The lack of dual-color images is the weakest point of this study. If it is technically impossible to add them, alternative analyses are needed to validate the main conclusions.

      1. Is BdPOLAR-mVenus functional? Although the authors interpret that weak BdPOLAR-mVenus expression partially rescued the bdpolar mutant phenotype in Fig. S4D, the localization pattern visualized by BdPOLAR-mVenus may not be completely reliable with this partial rescue activity.<br /> 2. Regardless of the functionality of the tagged protein, the authors need to provide more information on their localization. For example, is there a difference in polarity pattern depending on expression level? Does overexpressed BdPOLAR-mVenus invade the BdPAN1 zone? In such cases, might the loss of BdPOLAR polarity in the bdpan1 mutant be a side effect of overexpression, not PAN1 exclusion? Does BdPOLAR expression (no tag) show a dose-dependent effect, similar to the mVenus-tagged protein?<br /> 3. A major conclusion of this study was that the polarity domains of BdPOLAR and BdPAN1 are mutually exclusive. However, not all the cells in the figures were consistent with this statement. For example, the BdPOLAR signals at the GMC/SMC interphase appear to match BdPAN1 localization (compare 0:03 s in Video 1 and 0:20 s in Video 2 [top cell]). The 3D rendered image in Fig. 2F shows that BdPOLAR is excluded near the GMC on the front side of the SMC, where BdPAN1 is not localized. Some cells did not exhibit polarization (Fig. 3A, bottom left; Fig. 3E, bottom left). The most convincing data are the dual-color images of these two proteins. Otherwise, a sophisticated image analysis is required to support this conclusion.<br /> 4. Another central conclusion was that BdPOLAR was excluded at the future SC division site, marked with BdTANGLED1. However, these data are also not very convincing, as such specific exclusion cannot be seen in some figure panels (e.g., Fig. 3A, bottom left; Fig. 3E, all three cells on the left). If dual-color imaging is not feasible, a quantitative image analysis is needed to support this conclusion.<br /> 5. I could not find detailed imaging conditions and data processing methods. Are Figs. 2B and 2E max-projection or single-plane images? If they are single-plane images, which planes of the SMC are observed? In addition, how were Figs. 2C and 2F rendered? (e.g., number of images, distance intervals, processing procedures). This information is important for data interpretations.<br /> 6. [Minor point] The authors should clearly describe where BdPAN1 is expressed and localized. Is it expressed in the GMC and localized at the GMC/SMC interface? Alternatively, is it expressed and localized in the SMC?

    1. Reviewer #2 (Public Review):

      In the paper by Chadwick et al., the authors identify the molecular determinants of CO2 tolerance in the human fungal pathogen Cryptococcus neoformans. The authors have screened a collection of deletion mutants to identify the genes that are sensitive at 37oC (host temperature) and elevated CO2 levels. The authors identified that the genes responsible for CO2 sensitivity are involved in the pathways responsible for thermotolerance mechanisms such as Calcineurin, Ras1-Cdc24, cell wall integrity, and the Regulator of Ace2 and Morphogenesis (RAM) pathways. Moreover, they identified that the mutants of the RAM pathway effector kinase Cbk1 were most sensitive to elevated temperature and CO2 levels. This study uncovers the previously unknown role of the RAM pathway in CO2 tolerance. Transcriptome data indicates that the deletion of CBK1 results in an alteration in the expression of CO2-related genes. To identify the potential downstream targets of Cbk1, the authors performed a suppressor screen and obtained the spontaneous suppressor mutants that rescued the sensitivity of cbk1 mutants to elevated temperature and CO2. Through this screen, the authors identified two suppressor groups that showed a modest improvement in growth at 37{degree sign}C and in presence of CO2.<br /> Interestingly, from the suppressor screen, the authors identified a previously known interactor of Cbk1 which is SSD1, and an uncharacterized gene containing a putative Poly(A)-specific ribonuclease (PARN) domain named PSC1 (Partial Suppressor of cbk1Δ) which acts downstream of Cbk1. Deletion of these two genes in cbk1 null mutants rescued the sensitivity to elevated CO2 levels and temperature but did not fully rescue the ability to cause disease in mice.

      This study highlights the underappreciated role of the host CO2 tolerance and its importance in the ability of a fungal pathogen to survive and cause disease in host conditions. The authors claim to gain insight into the genetic components associated with carbon dioxide tolerance. The experimental results including the data presented, and conclusions drawn do justice to this claim. Overall, it is a well-written manuscript. However, some sections need improvement in terms of clarity and experimental design.

      • One major drawback of the study is the virulence assay performed to test the ability of cbk1 mutants to cause the disease in the mouse model. The cbk1 null mutants are thermosensitive in nature. Using these mutants, establishing the virulence attributes in mice would undermine the mutants' ability to infect mice as they won't be able to survive at the host body temperature.

      • The rationale for choosing the genes to test further is not clear in two instances in the study. a) From a list of 96 genes, how do the authors infer the pathways involved? Was any pathway analysis performed that helped them in shortlisting the pathways that they subsequently tested? A GO term analysis of the list of genes identified through the genetic screen would be more helpful to get an overview of the pathways involved in CO2 tolerance. b) The authors do not clearly mention why they chose only four genes to test for the CO2 sensitivity out of 16 downregulated genes identified from the nano string analysis.

      • It would be more useful to the readers if the authors could also include a thorough analysis of the presence of the putative PARN domain-containing protein across various fungal species rather than mentioning that it is only observed in C. neoformans and S. pombe. Also, the authors may want to discuss the known role(s) of SSD1, if any, in pathogenic ascomycetous yeasts so that the proposed functional divergence is supported further.