Structural basis for bacterial transcription-coupled DNA repair.
Coupling of transcription and DNA repair in bacteria is mediated by transcription-repair coupling factor (TRCF, the product of the mfd gene), which removes transcription elongation complexes stalled at DNA lesions and recruits the nucleotide excision repair machinery to the site. Here we describe the 3.2 A-resolution X-ray crystal structure of Escherichia coli TRCF. The structure consists of a compact arrangement of eight domains, including a translocation module similar to the SF2 ATPase RecG, and a region of structural similarity to UvrB. Biochemical and genetic experiments establish that another domain with structural similarity to the Tudor-like domain of the transcription elongation factor NusG plays a critical role in TRCF/RNA polymerase interactions. Comparison with the translocation module of RecG as well as other structural features indicate that TRCF function involves large-scale conformational changes. These data, along with a structural model for the interaction of TRCF with the transcription elongation complex, provide mechanistic insights into TRCF function.
The Rockefeller University, 1230 York Avenue, New York, NY 10021, USA.
Alexandra M
AM
Deaconescu
Anna L
AL
Chambers
Abigail J
AJ
Smith
Bryce E
BE
Nickels
Ann
A
Hochschild
Nigel J
NJ
Savery
Seth A
SA
Darst
D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D018360:Crystallography, X-Ray; D004265:DNA Helicases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D004260:DNA Repair; D004926:Escherichia coli / Q000235:genetics* / Q000378:metabolism*; D029968:Escherichia coli Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D008958:Models, Molecular; D008969:Molecular Sequence Data; D011487:Protein Conformation; D017434:Protein Structure, Tertiary; D017386:Sequence Homology, Amino Acid; D014157:Transcription Factors / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D014158:Transcription, Genetic
D001426:Bacterial Proteins; D029968:Escherichia coli Proteins; D014157:Transcription Factors; C058093:UvrB protein, E coli; C072103:transcription repair coupling factor protein, Bacteria; D004265:DNA Helicases