Mechanisms for Hfq-Independent Activation of rpoS by DsrA, a Small RNA, in Escherichia coli.

ABSTRACT: Many small RNAs (sRNAs) regulate gene expression by base pairing to their target messenger RNAs (mRNAs) with the help of Hfq in Escherichia coli. The sRNA DsrA activates translation of the rpoS mRNA in an Hfq-dependent manner, but this activation ability was found to partially bypass Hfq when DsrA is overproduced. The precise mechanism by which DsrA bypasses Hfq is unknown. In this study, we constructed strains lacking all three rpoS-activating sRNAs (i.e., ArcZ, DsrA, and RprA) in hfq⁺ and Hfq^- backgrounds, and then artificially regulated the cellular DsrA concentration in these strains by controlling its ectopic expression. We then examined how the expression level of rpoS was altered by a change in the concentration of DsrA

SUBMITTER: Kim W 

PROVIDER: S-EPMC6537650 | biostudies-literature | 2019 May

REPOSITORIES: biostudies-literature