MUTATION OF THE GENE ENCODING PROTEIN-KINASE C1 STIMULATES MITOTIC RECOMBINATION IN SACCHAROMYCES-CEREVISIAE

We have isolated a recessive allele of the yeast protein kinase C gene (PKC1) which promotes an elevated rate of mitotic recombination and c onfers a temperature-sensitive growth defect. The rate of recombinatio n was increased between genes in direct repeat and at a series of hete roalleles and was dependent upon the RAD52 gene product. The mutant pk c1 allele was sequenced and found to encode a single amino acid change within the catalytic domain. Osmotic stabilizing agents rescued the t emperature-sensitive growth defect but not the hyperrecombination phen otype, indicating that the two traits are separable. This separability suggests that the PKC1 gene product (Pkc1p) regulates DNA metabolism by an alternate pathway to that used in the regulation of cell lysis. The regulation of recombination is a previously unidentified role for Pkc1p.