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SRNA-Mediated Control of Transcription Termination in E. coli.

ABSTRACT: Bacterial small RNAs (sRNAs) have been implicated in various aspects of post-transcriptional gene regulation. Here, we demonstrate that sRNAs also act at the level of transcription termination. We use the rpoS gene, which encodes a general stress sigma factor ?(S), as a model system, and show that sRNAs DsrA, ArcZ, and RprA bind the rpoS 5'UTR to suppress premature Rho-dependent transcription termination, both in vitro and in vivo. sRNA-mediated antitermination markedly stimulates transcription of rpoS during the transition to the stationary phase of growth, thereby facilitating a rapid adjustment of bacteria to global metabolic changes. Next generation RNA sequencing and bioinformatic analysis indicate that Rho functions as a global "attenuator" of transcription, acting at the 5'UTR of hundreds of bacterial genes, and that its suppression by sRNAs is a widespread mode of bacterial gene regulation.

SUBMITTER: Sedlyarova N

PROVIDER: S-EPMC5040353 | biostudies-literature | 2016 Sep

REPOSITORIES: biostudies-literature

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sRNA-Mediated Control of Transcription Termination in E. coli.

Sedlyarova Nadezda N Shamovsky Ilya I Bharati Binod K BK Epshtein Vitaly V Chen Jiandong J Gottesman Susan S Schroeder Renée R Nudler Evgeny E

Cell 20160901 1

Bacterial small RNAs (sRNAs) have been implicated in various aspects of post-transcriptional gene regulation. Here, we demonstrate that sRNAs also act at the level of transcription termination. We use the rpoS gene, which encodes a general stress sigma factor σ(S), as a model system, and show that sRNAs DsrA, ArcZ, and RprA bind the rpoS 5'UTR to suppress premature Rho-dependent transcription termination, both in vitro and in vivo. sRNA-mediated antitermination markedly stimulates transcription ...[more]

PMID: 27662085

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