Download MendeleyThe carboxy-terminal coiled-coil of the RNA polymerase beta'-subunit is the main binding site for Gre factors.
Vassylyeva, M.N., Svetlov, V., Dearborn, A.D., Klyuyev, S., Artsimovitch, I., Vassylyev, D.G.(2007) EMBO Rep 8: 1038-1043
- PubMed: 17917675
- DOI: https://doi.org/10.1038/sj.embor.7401079
- Primary Citation of Related Structures:
2P4V - PubMed Abstract:
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.
Organizational Affiliation:
Department of Biochemistry and Molecular Genetics, Schools of Medicine and Dentistry, University of Alabama at Birmingham, Birmingham, Alabama 35294, USA.
