[New mutation in Saccharomyces cerevisiae SRM genes and some features of their phenotypic effects].

The effects of the previously identified mutations in nuclear genes SRM8, SRM12, SRM15, and SRM17 on the maintenance of chromosomes and recombinant plasmids in Saccharomyces cerevisiae cells and on cell sensitivity to ionizing radiation were studied. The srm8 mutation caused instability of chromosome maintenance in diploid cells. In yeast cells with the intact mitochondrial genome, all examined srm mutations decreased the mitotic stability of a centromeric recombinant plasmid with the chromosomal ARS element. Mutations srm12, srm15, and srm17 also decreased the mitotic stability of a centromereless plasmid containing the same ARS element, whereas the srm8 mutation did not markedly affect the maintenance of this plasmid. Mutations srm8, srm12, and srm17 were shown to increase cell sensitivity to gamma-ray irradiation. The SRM8 gene was mapped, cloned, and found to correspond to the open reading frame YJLO76w in chromosome X.