title: Starvation for a specific amino acid induces high frequencies of rho- mutants in Saccharomyces cerevisiae.
abstract: Auxotrophic yeast cells were starved on solid media for their respective essential amino acid in the course of "adaptive mutation" experiments. Thereby, high proportions of mitochondrially respiratory deficient (rho-) mutants accumulated among the cells stressed on selective plates. Using a strain with a plus-four frameshift mutation in a chromosomal gene involved in lysine biosynthesis, we observed that many of the revertant colonies which arose late under the selective pressure were composed of mixtures of rho+ and rho- cells, indicating that they originated from founder cells containing intact as well as defective mitochondrial genomes. We show that in spite of the slower growth of rho- cells the late-appearing colonies cannot be interpreted as descending from rho- revertants present before selective plating.
authors.affiliation: Department of Molecular Genetics, Institute of Tumor Biology and Cancer Research, University of Vienna, Borschkegasse 8a, A-1090 Vienna, Austria.
authors.forename: E
authors.initials: E
authors.lastname: Heidenreich
authors.forename: U
authors.initials: U
authors.lastname: Wintersberger
mesh_terms: D000222:Adaptation, Physiological; D019069:Cell Respiration / Q000502:physiology*; D002470:Cell Survival / Q000502:physiology; D016368:Frameshift Mutation; D008239:Lysine / Q000096:biosynthesis*; D012441:Saccharomyces cerevisiae / Q000235:genetics*; D013217:Starvation
chemical_list: D008239:Lysine