CsrA
- Editor's Pick Research Article | Molecular Biology and PhysiologyCsrA-Mediated Translational Activation of ymdA Expression in Escherichia coli
The Csr system of E. coli controls gene expression and physiology on a global scale. CsrA protein, the central component of this system, represses translation initiation of numerous genes by binding to target transcripts, thereby competing with ribosome binding. Variations of this mechanism are so common that CsrA is sometimes called a translational repressor....
- Research Article | Host-Microbe BiologyControl of Type III Secretion System Effector/Chaperone Ratio Fosters Pathogen Adaptation to Host-Adherent Lifestyle
Host colonization by extracellular pathogens often entails the transition from a planktonic lifestyle to a host-attached state. Enteropathogenic E. coli (EPEC), a Gram-negative pathogen, attaches to the intestinal epithelium of the host and employs a type III secretion system (T3SS) to inject effector proteins into the cytoplasm of infected cells. The most abundant...
- Research Article | Molecular Biology and PhysiologyRegulation of Iron Storage by CsrA Supports Exponential Growth of Escherichia coli
Iron is an essential micronutrient for nearly all living organisms but is toxic in excess. Consequently, the maintenance of iron homeostasis is a critical biological process, and the genes involved in this function are tightly regulated. Here, we explored a new role for the bacterial RNA binding protein CsrA in the regulation of iron homeostasis. CsrA was shown to be a key regulator of iron storage genes in...
- Research Article | Molecular Biology and PhysiologyVibrio cholerae CsrA Directly Regulates varA To Increase Expression of the Three Nonredundant Csr Small RNAs
Vibrio cholerae is a major human pathogen, causing epidemics and pandemics of cholera. V. cholerae persists in the aquatic environment, providing a constant source for human infection. Success in transitioning from the environment to the human host and back requires the bacterium to rapidly respond...
- Research ArticleTranslational Repression of the RpoS Antiadapter IraD by CsrA Is Mediated via Translational Coupling to a Short Upstream Open Reading Frame
CsrA posttranscriptionally represses gene expression associated with stationary-phase bacterial growth, often in opposition to the transcriptional effects of the stationary-phase sigma factor RpoS. We show that CsrA employs a novel regulatory mechanism to repress translation of iraD, which encodes an antiadapter protein that protects RpoS against proteolysis. CsrA binds to four sites in the iraD leader transcript but...