title: The induction of rho- mutants by UV or gamma-rays is independent of the nuclear recombinational repair pathway in Saccharomyces cerevisiae.
abstract: In order to discover whether the nuclear recombinational repair pathway also acts on lesions induced in mitochondrial DNA (mtDNA), the possible role of the RAD50, -51, -52, -55 and -56 genes on the induction of rho- mutants by radiations was studied. Such induction appeared to be independent of this pathway. Nevertheless, an efficient induction of respiration-deficient mutants was observed in gamma-irradiated rad52 diploids. We demonstrate that these mutants do not result from a lack of mtDNA repair, but from chromosome losses induced by gamma-rays. Such an impairment of the respiratory ability of diploids by chromosome losses was effectively observed in the aneuploid progeny of unirradiated RAD+ cdc6 diploids incubated at the restrictive temperature.
mesh_terms: D002875:Chromosomes / Q000528:radiation effects; D004260:DNA Repair; D004272:DNA, Mitochondrial / Q000235:genetics / Q000528:radiation effects; D004307:Dose-Response Relationship, Radiation; D005720:Gamma Rays; D005838:Genotype; D009154:Mutation; D011995:Recombination, Genetic / Q000528:radiation effects*; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000254:growth & development / Q000528:radiation effects*; D014466:Ultraviolet Rays
chemical_list: D004272:DNA, Mitochondrial