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Structural basis of DNA recognition by the alternative sigma-factor, sigma54.

ABSTRACT: The sigma subunit of bacterial RNA polymerase (RNAP) regulates gene expression by directing RNAP to specific promoters. Unlike sigma(70)-type proteins, the alternative sigma factor, sigma(54), requires interaction with an ATPase to open DNA. We present the solution structure of the C-terminal domain of sigma(54) bound to the -24 promoter element, in which the conserved RpoN box motif inserts into the major groove of the DNA. This structure elucidates the basis for sequence specific recognition of the -24 element, orients sigma(54) on the promoter, and suggests how the C-terminal domain of sigma(54) interacts with RNAP.

SUBMITTER: Doucleff M

PROVIDER: S-EPMC2680387 | biostudies-literature | 2007 Jun

REPOSITORIES: biostudies-literature

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Structural basis of DNA recognition by the alternative sigma-factor, sigma54.

Doucleff Michaeleen M Pelton Jeffrey G JG Lee Peter S PS Nixon B Tracy BT Wemmer David E DE

Journal of molecular biology 20070412 4

The sigma subunit of bacterial RNA polymerase (RNAP) regulates gene expression by directing RNAP to specific promoters. Unlike sigma(70)-type proteins, the alternative sigma factor, sigma(54), requires interaction with an ATPase to open DNA. We present the solution structure of the C-terminal domain of sigma(54) bound to the -24 promoter element, in which the conserved RpoN box motif inserts into the major groove of the DNA. This structure elucidates the basis for sequence specific recognition o ...[more]

PMID: 17481658

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