The BarA/UvrY-CsrA regulatory circuitry in Escherichia coli and others γ-proteobacteria

Abstract

The BarA/UvrY two-component system of Escherichia coli directly activates the expression of the small non-coding RNAs CsrB and CsrC. These small RNAs function as antagonist of the CsrA activity, which regulates the translation of numerous target mRNAs. The BarA/UvrY-CsrA circuitry is conserved in the γ-proteobacteria and although the mechanism of action is preserved, there are important functional differences that represent the particular requirements of each bacterial species. In this review we compare the strategies that different bacterial species employ in order to carry out the regulation of the above circuitry in function of their life style.