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A regulatory protein that interferes with activator-stimulated transcription in bacteria.

ABSTRACT: Transcriptional activator proteins in bacteria often operate by interaction with the C-terminal domain of the alpha-subunit of RNA polymerase (RNAP). Here we report the discovery of an "anti-alpha" factor Spx in Bacillus subtilis that blocks transcriptional activation by binding to the alpha-C-terminal domain, thereby interfering with the capacity of RNAP to respond to certain activator proteins. Spx disrupts complex formation between the activator proteins ResD and ComA and promoter-bound RNAP, and it does so by direct interaction with the alpha-subunit. ResD- and ComA-stimulated transcription requires the proteolytic elimination of Spx by the ATP-dependent protease ClpXP. Spx represents a class of transcriptional regulators that inhibit activator-stimulated transcription by interaction with alpha.

SUBMITTER: Nakano S

PROVIDER: S-EPMC153076 | biostudies-literature | 2003 Apr

REPOSITORIES: biostudies-literature

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A regulatory protein that interferes with activator-stimulated transcription in bacteria.

Nakano Shunji S Nakano Michiko M MM Zhang Ying Y Leelakriangsak Montira M Zuber Peter P

Proceedings of the National Academy of Sciences of the United States of America 20030317 7

Transcriptional activator proteins in bacteria often operate by interaction with the C-terminal domain of the alpha-subunit of RNA polymerase (RNAP). Here we report the discovery of an "anti-alpha" factor Spx in Bacillus subtilis that blocks transcriptional activation by binding to the alpha-C-terminal domain, thereby interfering with the capacity of RNAP to respond to certain activator proteins. Spx disrupts complex formation between the activator proteins ResD and ComA and promoter-bound RNAP, ...[more]

PMID: 12642660

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