UV and chemical mutagenesis in rev7 mutants of yeast

✍ Scribed by Lawrence, Christopher W. ;Nisson, Paul E. ;Christensen, Roshan B.

• Publisher: Springer
• Year: 1985
• Tongue: English
• Weight: 601 KB
• Volume: 200
• Category: Article
• ISSN: 0026-8925
• DOI: 10.1007/bf00383317

✦ Synopsis

We have examined induced mutagenesis in rev7-1 mutants of Baker's yeast' Saccharomyces cerevisiae, using a variety of contrasting test systems and several different mutagens. UV-induced reversion frequencies of the ochre allele arg4-17, the putative missense allele ilvl-92 and the frameshift allele his4-38 were 10 to 200 fold lower in haploid and diploid rev7-1 mutants compared with wild type strains, but UV-induced reversion frequencies of the frameshift allele leu2-3 and the proline missense allele cyc1-115 were reduced only a few fold. Ilvl-92 reversion frequencies induced by methyl methane sulfonate or by N-methyl-N'nitro-N-nitrosoguanidine were 10 to 20 times lower in rev7-1 mutants, but normal frequencies of these revertants were induced with ethyl methane sulfonate, even though rev7-1 strains are slightly sensitive to this mutagen as well as to the others tested. We conclude that the rev7 mutants, like the rev3 mutants they closely resemble, have a substantial but not total deficiency concerning induced mutagenesis.