- Sep 2016
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scienceintheclassroom.org scienceintheclassroom.org
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Bmp4 is also shown for lizard. Red double-headed arrows indicate the body region processed for sectioning.
the authors have also managed to demonstrate the expression of Bmp4 in lizard, which strongly suggests a developmental evolutionary link between all reptiles, and birds and mammals.
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immunohistochemistry
The process for detecting antigens in tissues by using the principle that antibodies binding specifically to antigens.
And this method is used in the recognition of abnormal cells, and for visualising the distribution and localization of specific cellular components.
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Hematoxylin and eosin (H&E)
Histologists- those who study tissues- dye different parts of cells prior to studying them under microscope.
H&E is a widely used staining, which makes nuclei blue and the plasma pink, respectively.
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whole-mount in situ hybridization (WMISH) with species-specific probes, we show that crocodile, lizard, and snake placodes all exhibit spatial expression of Shh
The WMISH experiments (used to detect gene expression) show that Shh, a morphogen needed in development, was expressed in the placode.
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Finally, similar in situ hybridization analyses indicate the presence and total absence of Bmp4 dermal expression in wild-type and scaleless dragons, respectively
ISH (in situ hybridisation) was used to show that the expression of the BMP4 gene.
It was found that it was expressed in the wild type but not the mutant.
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The most marked and derived macropatterning of skin in reptiles is observed in snakes
The features of snake skin developed was visualised with WMISH, showing that snakes have a unique pattern of development of scales.
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Our WMISH experiments, with early developmental scale markers, such as Shh and Ctnnb1, on developmental series of Nile crocodiles and bearded dragon lizards clearly indicate
WMISH (Whole-mount in situ hybridization) was the experiment technique used. This is a technique which labels RNA using fluorescence etc.
RNA is produced by genes that are being expressed so by seeing what RNA there is, we can see what genes are being used.
In this study, WMISH was used to detect RNA of developmental genes (e.g. Shh, Ctnnb1) in crocodiles and bearded dragon lizards.
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proliferating cell nuclear antigen (PCNA) analyses indicate a reduced proliferation rate of the placode epidermal cells
proliferating cell nuclear antigen (PCNA) is a protein which is necessarry in replication, and therefore if it is detected, this means the cells will be reproducing.
this analysis showed that the cells of the placode were reproducing very slowly.
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Our serial sectioning and histological analyses of skin developmental series (Fig. 1A) in crocodiles (Crocodylus niloticus), bearded dragon lizards (P. vitticeps), and corn snakes
Serial sectioning is successive microscopic images of histological- which means tissues. Here, microscopic images were taken of different body parts of the lizard and and snakes, focussing on where scales form.
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