Evidence for short-patch mismatch repair in $Saccharomyces\ cerevisiae$

International audienceRecombination events between non-identical sequences most often involve heteroduplex DNA intermediates that are subjected to mismatch repair. The well-characterized long-patch mismatch repair process, controlled in eukaryotes by bacterial MutS and MutL orthologs, is the major system involved in repair of mispaired bases. Here we present evidence for an alternative short-patch mismatch repair pathway that operates on a broad spectrum of mismatches. In msh2 mutants lacking the long-patch repair system, sequence analysis of recombination tracts resulting from exchanges between similar but non-identical (homeologous) parental DNAs showed the occurrence of short-patch repair events that can involve