Alterations in the physical characteristics of mitochondrial DNA accompanied increased spontaneous mutability to cytoplasmic respiratory-deficiency in yeast. Two systems were used to modify mutation rates, one physiological, the other genetic. Cells in log phase were shown to be more mutable than cells in stationary phase, and glucose-repressed cells were shown to be more mutable than unrepressed cells. A nuclear gene which acts as a mitochondrial mutator was found to increase spontaneous mutation rate by a factor of ten. An increase in endogenous formation of G+C-rich fragments of mt-DNA accompanied a physiological state conducive to higher mutability, and it is proposed that increasedin vivo digestion of A+T-rich regions is involved in these alterations. Greater nuclease(s) activity accompanied the presence of the mutator gene, and it is proposed that this gene is concerned with the regulation of nuclease activity or with repair mechanisms.
Stationary Phase Physiological State Mutator Gene Physical Characteristic Mutation Rate
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.
This is a preview of subscription content, log in to check access.
Bernardi, G., Faures, M., Piperno, G., Slonimski, P.P.: Mitochondrial DNA's from respiratory-sufficient and cytoplasmic respiratory-deficient mutant yeast. J. molec. Biol.48, 23–42 (1970)PubMedCrossRefGoogle Scholar
Dujon, B., Slonimski, P.P., Weill, L.: Mitochondrial genetics IX: A model for recombinations and segregation of mitochondrial genomes inSaccharomyces cerevisiae. Genetics78, 415–437 (1974)PubMedGoogle Scholar
Ephrussi, B., Hottinguer, H.: On an unstable cell state in yeast. Cold Spr. Harb. Symp. quant. Biol.16, 75–85 (1951)Google Scholar
Goldthwaite, C.D., Cryer, D.R., Marmur, J.: Effect of carbon source on the replication and transmission of yeast mitochondrial genomes. Molec. Gen. Genet.133, 87–104 (1974)PubMedCrossRefGoogle Scholar
James, A.P., Johnson, B.F., Inhaber, E.R., Gridgeman, N.T.: A kinetic analysis of spontaneousρ− mutations in yeast. Mutation Res.30, 199–208 (1975)PubMedCrossRefGoogle Scholar
Michaelis, G., Douglass, S., Tsai, M., Criddle, R.S.: Mitochondrial DNA and suppressiveness of petite mutants inSaccharomyces cerevisiae. Biochem. Genet.5, 487–495 (1971)PubMedCrossRefGoogle Scholar
Prunell, A., Bernardi, G.: The mitochondrial genome of wild-type yeast cells IV. Genes and Spacers. J. molec. Biol.86, 825–841 (1974)PubMedCrossRefGoogle Scholar
Storti, R.V., Sinclair, J.H.: Sequence homology between mitochondrial DNA and nuclear DNA in years. Biochemistry13, 4447–4455 (1974)PubMedCrossRefGoogle Scholar
Williamson, D.H., Fenell, D.J.: Apparent dispersive replication of yeast mitochondrial DNA as revealed by density labelling experiments. Molec. gen. Genet.131, 193–207 (1974)PubMedCrossRefGoogle Scholar
Zeman, L., Lusena, C.V.: DNA synthesis in isolated yeast mitochondria. Canad. J. Biochem.52, 941–949 (1974)Google Scholar
Zeman, L., Lusena, C.V.: Preferential digestion of A+T-rich stretches of yeast mitochondrial DNA in isolated mitochondria. Europ. J. Biochem.57, 561–567 (1975)PubMedCrossRefGoogle Scholar