Mapping DNA sequence to transcription factor binding energy in vivo

“Mapping DNA sequence to transcription factor binding energy in vivo” by Stephanie L Barnes, Nathan M Belliveau, William T Ireland, Justin B Kinney and Robert Phillips https://doi.org/10.1101/331124 In this article, Barnes and colleagues constructed a libraries of strains in which GFP expression is controlled by a transcription factor, and the transcription factor (TF) binding sites were randomly mutated. Libraries were sorted by GFP fluorescence and sequenced to determine the likelihood that a given binding site corresponds to a range of fluroescence. »

Active degradation of a regulator controls coordination of downstream genes

“Active degradation of a regulator controls coordination of downstream genes” by Nicholas A. Rossi, Thierry Mora, Aleksandra M. Walczak, and Mary J. Dunlop https://doi.org/10.1101/272120 In this article, Rossi and colleagues observed how noise develops in the expression of genes downstream of stress response activator gene MarA by manipulating MarA degradation and expression levels and then measuring variability in downstream gene expression in single cells. As the authors note, active degradation is rare in rapidly growing bacterial cells and imposes a significant fitness cost. »