PMID: 17481658 , Related PDB ids: 2O8K, 2O9L

Authors:

Doucleff M, Pelton JG, Lee PS, Nixon BT, Wemmer DE

Title:

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

Journal:

J Mol Biol. 2007 Jun 15;369(4):1070-8. Epub 2007 Apr 12.

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.