CHARACTERIZATION OF 2 PROTEIN-KINASES FROM SCHIZOSACCHAROMYCES-POMBE INVOLVED IN THE REGULATION OF DNA-REPAIR

We have identified two novel genes designated hhpl(+) and hhp2(+) in the fission yeast Schizosaccharomyces pombe. The hhpl(+) and hhp2(+) genes encode two closely related protein kinases that share significant sequence identities with Hrr25p from Saccharomyces cerevisiae. Characterization of strains harboring single and double mutations in the hhp(+) genes reveals DNA repair defects in these cells. Schizosaccharomyces pombe strains lacking either or both Hhp activities reveal differences in their ability to withstand DNA lesions caused by either methyl methanesulfonate (MMS) or gamma-rays which correlate with their ability to repair DNA strand breaks caused by these agents. We suggest that Hhpl and Hhp2 are involved in the regulation of distinct and overlapping DNA repair pathways in S.pombe.