Structural basis of a protein partner switch that regulates the general stress response of a-proteobacteria

摘要

Organisms regulate their gene expression in response to physical and chemical changes in their environment. The first- step of gene expression is transcription of DNA into Mrna by RNA polymerase. Bacteria use a diverse set of sensory and regulatory strategies to control transcription in response to environmental perturbations. The PhyR protein of the a-proteobacteria uniquely links two distinct modes of transcriptional control: (ⅰ) two-component signal transduction and (ⅱ) regulation of the sigma (σ) subunit of RNA polymerase. Here, we define the structural basis by which Caulobacter crescentus PhyR functions to bridge these regulatory systems to control transcription in response to environmental stress.