The active site of the DNA repair endonuclease XPF-ERCC1 forms a highly conserved nuclease motif

摘要: XPF-ERCC1 is a structure-specific endonuclease involved in nucleotide excision repair, interstrand crosslink repair and homologous recombination. So far, it has not been shown experimentally which subunit of the heterodimer harbors nuclease activity amino acids contribute to catalysis. We used an affinity cleavage assay located active site 670-740 XPF. Point mutations generated this region were analyzed for their role activity, metal coordination DNA binding. Several acidic basic residues turned out be required but The separation substrate binding catalysis by will invaluable studying protein various processes. Alignment XPF with proteins belonging Mus81 family putative archaeal RNA helicase reveals that seven are absolutely conserved three families, indicating they share common motif.