2p4v
From Proteopedia
| |||||||
| , resolution 2.6Å | |||||||
|---|---|---|---|---|---|---|---|
| Gene: | greB (Escherichia coli) | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
Crystal structure of the transcript cleavage factor, GreB at 2.6A resolution
Overview
Bacterial Gre transcript cleavage factors stimulate the intrinsic endonucleolytic activity of RNA polymerase (RNAP) to rescue stalled transcription complexes. They bind to RNAP and extend their coiled-coil (CC) domains to the catalytic centre through the secondary channel. Three existing models for the Gre-RNAP complex postulate congruent mechanisms of Gre-assisted catalysis, while offering conflicting views of the Gre-RNAP interactions. Here, we report the GreB structure of Escherichia coli. The GreB monomers form a triangle with the tip of the amino-terminal CC of one molecule trapped within the hydrophobic cavity of the carboxy-terminal domain of a second molecule. This arrangement suggests an analogous model for recruitment to RNAP. Indeed, the beta'-subunit CC located at the rim of the secondary channel has conserved hydrophobic residues at its tip. We show that substitutions of these residues and those in the GreB C-terminal domain cavity confer defects in GreB activity and binding to RNAP, and present a plausible model for the RNAP-GreB complex.
About this Structure
2P4V is a Single protein structure of sequence from Escherichia coli. Full crystallographic information is available from OCA.
Reference
The carboxy-terminal coiled-coil of the RNA polymerase beta'-subunit is the main binding site for Gre factors., Vassylyeva MN, Svetlov V, Dearborn AD, Klyuyev S, Artsimovitch I, Vassylyev DG, EMBO Rep. 2007 Nov;8(11):1038-43. Epub 2007 Oct 5. PMID:17917675
Page seeded by OCA on Thu Mar 20 18:08:38 2008
