Spontaneous Mitotic Recombination in the MMS8-1 Mutant of Saccharomyces Cerevisiae

摘要

The MMS sensitive mutation mms8-1 increases the rate of spontaneous mitotic intragenic recombination at five heteroallelic loci on three chromosomes. Complementation, segregation, and mapping studies indicate that mms8-1 is allelic to cdc9, known to be defective in DNA ligase. Both mms8-1 and cdc9 mutants are lethal in combination with the recombination defective mutant rad52-1. Genetic analysis of spontaneous red/white sectors in an ade2-1/ade2-1 ade5/+ mms8-1/mms8-1 strain shows non-reciprocal recombinational events involving long chromosome segments. We also observe increased rates of simultaneous recombination at loci on different chromosomes in both wild type and mms8-1 mutants. (ERA citation 06:016160)