sRNAs that repress transcription have been engineered to create orthogonal and composable regulators that can be used to construct RNA-only transcriptional networks

The basal level of T7-dependent tran-scription in this strain can be reduced by constitutive produc-tion of T7 lyzozyme, a natural inhibitor of T7 RNAP, usingplasmids pLysS and pLysE

genetic devices have been designed for suppressing leaky basal expression levels through the engineering of super‐repressors (Ruegg et al, 2018), exploitation of antisense RNAs (O'Connor & Timmis, 1987), or physical decoupling of regulatory elements along with conditional proteolysis

the leakiness and inducibility of the ligand-inducible LacI repressor mutants have been quantified and classified

Consequently, the plasmid donor cells do not express gfp

We have demonstrated that small RNAs can tightly repress their target genes when their synthesis rate is smaller than some threshold, but have little or no effect when the synthesis rate is much larger than that threshold

In particular, small RNAs are shown to establish a threshold for the expression of their target, providing safety mechanism against random fluctuations and transient signals. The threshold level is set by the transcription rate of the small RNA and can thus be modulated dynamically to reflect changing environmental conditions.

in the absence of tamoxifen, it exhibits some activity

strong promoters capable of driving expression of microbial opsins or fluorescent proteins in specific populations can exhibit leaky expression elsewhere. This low-level leak may be virtually undetectable as light responsiveness or fluorescence but can be a serious issue when expressing Cre recombinase.

it can be useful for reducing leaky expression of toxic proteins

We report the construction of a family of vectors that contain a reengineered lacIq-lac promoter-operator complex in which cloned genes are strongly repressed in the absence of inducer.