StpA and H-NS ChIP-chip analysis
Ontology highlight
ABSTRACT:
ORGANISM(S): Escherichia coli
SUBMITTER: Naotake Ogasawara
PROVIDER: E-MEXP-1880 | biostudies-arrayexpress |
REPOSITORIES: biostudies-arrayexpress
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Project description:Bacterial Gre factors associate with RNA polymerase (RNAP) and stimulate intrinsic cleavage of the nascent transcript at the active site of RNAP. Biochemical and genetic studies to date have shown that E. coli Gre factors prevent transcriptional arrest during elongation and enhance transcription fidelity. Furthermore, Gre factors participate in stimulation of promoter escape and suppression of promoter-proximal pausing during beginning of RNA synthesis in E. coli. Although Gre factors are conserved in general bacteria, limited functional studies have been performed in bacteria other than E. coli. In this investigation, ChAP-chip analysis was conducted to visualize the distribution of B. subtilis GreA on the chromosome and determine the effects of GreA inactivation on core RNAP trafficking. Our data show that GreA is uniformly distributed in the transcribed region from the promoter to coding region with core RNAP, and its inactivation induces RNAP accumulation at many promoter or promoter-proximal regions. Based on these findings, we propose that GreA would constantly associate with core RNAP during transcriptional initiation and elongation, and resolves its stalling at promoter or promoter-proximal regions, thus contributing to the even distribution of RNAP along the promoter and coding regions in B. subtilis cells.
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