title: Regulation and rate enhancement during transcription-coupled DNA repair.
abstract: Transcription-coupled DNA repair (TCR) is a subpathway of nucleotide excision repair (NER) that is triggered when RNA polymerase is stalled by DNA damage. Lesions targeted by TCR are repaired more quickly than lesions repaired by the transcription-independent "global" NER pathway, but the mechanism underlying this rate enhancement is not understood. Damage recognition during bacterial NER depends upon UvrA, which binds to the damage and loads UvrB onto the DNA. Bacterial TCR additionally requires the Mfd protein, a DNA translocase that removes the stalled transcription complexes. We have determined the properties of Mfd, UvrA, and UvrB that are required for the elevated rate of repair observed during TCR. We show that TCR and global NER differ in their requirements for damage recognition by UvrA, indicating that Mfd acts at the very earliest stage of the repair process and extending the functional similarities between TCR in bacteria and eukaryotes.
authors.affiliation: DNA-Protein Interactions Unit, School of Biochemistry, University of Bristol, Bristol BS8 1TD, UK.
authors.forename: Laura
authors.initials: L
authors.lastname: Manelyte
authors.forename: Young-In T
authors.initials: YI
authors.lastname: Kim
authors.forename: Abigail J
authors.initials: AJ
authors.lastname: Smith
authors.forename: Rachel M
authors.initials: RM
authors.lastname: Smith
authors.forename: Nigel J
authors.initials: NJ
authors.lastname: Savery
mesh_terms: D000251:Adenosine Triphosphatases / Q000235:genetics / Q000378:metabolism; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D004265:DNA Helicases / Q000235:genetics / Q000378:metabolism; D004260:DNA Repair; D004269:DNA, Bacterial / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism; D029968:Escherichia coli Proteins / Q000235:genetics / Q000378:metabolism; D008954:Models, Biological; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism; D014158:Transcription, Genetic / Q000235:genetics*
chemical_list: D001426:Bacterial Proteins; D004269:DNA, Bacterial; D004268:DNA-Binding Proteins; D029968:Escherichia coli Proteins; D014157:Transcription Factors; C058093:UvrB protein, E coli; C072103:transcription repair coupling factor protein, Bacteria; C068631:UvrA protein, E coli; D000251:Adenosine Triphosphatases; D004265:DNA Helicases