Nucleotide excision repair.
Nucleotide excision repair is the major DNA repair mechanism in all species tested. This repair system is the sole mechanism for removing bulky adducts from DNA, but it repairs essentially all DNA lesions, and thus, in addition to its main function, it plays a back-up role for other repair systems. In both pro- and eukaryotes nucleotide excision is accomplished by a multisubunit ATP-dependent nuclease. The excision nuclease of prokaryotes incises the eighth phosphodiester bond 5' and the fourth or fifth phosphodiester bond 3' to the modified nucleotide and thus excises a 12-13-mer. The excision nuclease of eukaryotes incises the 22nd, 23rd, or 24th phosphodiester bond 5' and the fifth phosphodiester bond 3' to the lesion and thus removes the adduct in a 27-29-mer. A transcription repair coupling factor encoded by the mfd gene in Escherichia coli and the ERCC6 gene in humans directs the excision nuclease to RNA polymerase stalled at a lesion in the transcribed strand and thus ensures preferential repair of this strand compared to the nontranscribed strand.
Department of Biochemistry and Biophysics, University of North Carolina School of Medicine, Chapel Hill 27599.
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D000818:Animals; D001419:Bacteria / Q000235:genetics / Q000528:radiation effects; D004249:DNA Damage; D004265:DNA Helicases / Q000235:genetics / Q000378:metabolism; D004260:DNA Repair; D045643:DNA Repair Enzymes; D012321:DNA-Directed RNA Polymerases / Q000378:metabolism; D004926:Escherichia coli / Q000235:genetics / Q000528:radiation effects; D005798:Genes, Bacterial; D005800:Genes, Fungal; D006801:Humans; D000075223:Poly-ADP-Ribose Binding Proteins; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000528:radiation effects; D014466:Ultraviolet Rays
D000075223:Poly-ADP-Ribose Binding Proteins; D012321:DNA-Directed RNA Polymerases; D004265:DNA Helicases; C078673:ERCC6 protein, human; D045643:DNA Repair Enzymes