| Title: | Mutations leading to expression of the cryptic HMRa locus in the yeast Saccharomyces cerevisiae |
| DOI: | 10.1093/genetics/109.3.481 |
| ISSN/ISBN: | 0016-6731 (Print) 0016-6731 (Linking) |
| Abstract: | "Mutations leading to expression of the silent HMRa information in Saccharomyces cerevisiae result in sporulation proficiency in mata1/MAT alpha diploids. An example of such a mutation is sir5-2, a recessive mutation in the gene SIR5. As expected, haploids carrying the sir5-2 mutation are nonmaters due to the simultaneous expression of HMRa and HML alpha, resulting in the nonmating phenotype of an a/alpha diploid. However, sir5-2/sir5-2 mata1/MAT alpha diploids mate as alpha yet are capable of sporulation. The sir5-2 mutation is unlinked to sir1-1, yet the two mutations do not complement each other: mata1/MAT alpha sir5-2/SIR5 SIR1/sir1-1 diploids are capable of sporulation. In this case, recessive mutations in two unlinked genes form a mutant phenotype, in spite of the presence of the normal wild-type alleles. The PAS1-1 mutation, Provider of a Sporulation function, is a dominant mutation tightly linked to HMRa. PAS1-1 does not affect the mating ability of a strain, yet it allows diploids lacking a functional MATa locus to sporulate. It is proposed that PAS1-1 leads to partial expression of the otherwise cryptic a1 information at HMRa" |
| Keywords: | "Animals Gene Expression Regulation *Genes, Fungal Mating Factor Mutation Peptides/genetics Pheromones/genetics Saccharomyces cerevisiae/*genetics Spores, Fungal;" |
| Notes: | "MedlineKassir, Y Simchen, G eng Research Support, Non-U.S. Gov't 1985/03/01 Genetics. 1985 Mar; 109(3):481-92. doi: 10.1093/genetics/109.3.481" |
