Specific Cleavage of Model Recombination and Repair Intermediates by the Yeast Rad1-Rad10 DNA Endonuclease

The RAD1 and RADIO genes of Saccharomyces cerevisiae are required for both nucleotide excision repair and certain mitotic recombination events. Here, model recombination and repair intermediates were used to show that Rad1 -Rad10-mediated cleavage occurs at duplex-single-strand junctions. Moreover, cleavage occurs only on the strand containing the 3' single-stranded tail. Thus, both biochemical and genetic evidence indicate a role for the Rad1-Rad10 complex in the cleavage of specific recombination intermediates. Furthermore, these data suggest that Rad1-Rad10 endonuclease incises DNA 5' to damaged bases during nucleotide excision repair.