Structural basis for the bacterial transcription-repair coupling factor/RNA polymerase interaction.
Publication Type:Journal Article
Source:Nucleic Acids Res, Volume 38, Issue 22, p.8357-69 (2010)
Keywords:Amino Acid Sequence, Amino Acid Substitution, Bacterial Proteins, Crystallography, X-Ray, DNA-Directed RNA Polymerases, Models, Molecular, Molecular Sequence Data, Protein Interaction Domains and Motifs, Transcription Factors, Two-Hybrid System Techniques
<p>The transcription-repair coupling factor (TRCF, the product of the mfd gene) is a widely conserved bacterial protein that mediates transcription-coupled DNA repair. TRCF uses its ATP-dependent DNA translocase activity to remove transcription complexes stalled at sites of DNA damage, and stimulates repair by recruiting components of the nucleotide excision repair pathway to the site. A protein/protein interaction between TRCF and the β-subunit of RNA polymerase (RNAP) is essential for TRCF function. CarD (also called CdnL), an essential regulator of rRNA transcription in Mycobacterium tuberculosis, shares a homologous RNAP interacting domain with TRCF and also interacts with the RNAP β-subunit. We determined the 2.9-Å resolution X-ray crystal structure of the RNAP interacting domain of TRCF complexed with the RNAP-β1 domain, which harbors the TRCF interaction determinants. The structure reveals details of the TRCF/RNAP protein/protein interface, providing a basis for the design and interpretation of experiments probing TRCF, and by homology CarD, function and interactions with the RNAP.</p>