The effects of mismatch repair and RAD1 genes on interchromosomal crossover recombination in Saccharomyces cerevisiae.

We have previously shown that recombination between 400-bp substrates containing only 4-bp differences, when present in an inverted repeat orientation, is suppressed by >20-fold in wild-type strains of S. cerevisiae. Among the genes involved in this suppression were three genes involved in mismatch repair--MSH2, MSH3, and MSH6--and one in nucleotide excision repair, RAD1.

A new reversion assay for measuring all possible base pair substitutions in Saccharomyces cerevisiae.

A TRP5-based reversion system that allows the rates of all possible base pair substitutions to be measured when the TRP5 locus is in both orientations relative to a defined origin of replication has been developed. This system should be useful for a wide variety of mutation and repair studies in yeast.