Analysis of mutagenic DNA repair in a thermoconditional mutant of Saccharomyces cerevisiae. III. Dose-response pattern of mutation induction in UV-irradiated rev2ts cells.
Recent studies regarding the influence of cycloheximide on the temperature-dependent increase in survival and mutation frequencies of a thermoconditional rev2 mutant lead to the suggestion that the REV2-coded mutagenic repair function is UV-inducible. In the present study we show that stationary-phase rev2ts cells are characterized by a biphasic linear-quadratic dose-dependence of mutation induction ("mutation kinetics") of ochre alleles at 23 degrees C (permissive temperature) but linear kinetics at the restrictive temperature of 36 degrees C. Mathematical analysis using a model based on Poisson statistics and a further mathematical procedure, the calculation of "apparent survival", support the assumption that the quadratic component of the reverse mutation kinetics investigated can be attributed to a UV-inducible component of mutagenic DNA repair controlled by the REV2 gene.
D004260:DNA Repair; D004307:Dose-Response Relationship, Radiation; D008433:Mathematics; D008957:Models, Genetic; D009154:Mutation; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000528:radiation effects*; D013045:Species Specificity; D014466:Ultraviolet Rays