Mutations Leading to Expression of the Cryptic HMR a Locus in the Yeast SACCHAROMYCES CEREVISIAE
AUTOR(ES)
Kassir, Yona
RESUMO
Mutations leading to expression of the silent HMR a information in Saccharomyces cerevisiae result in sporulation proficiency in mata1/MATα 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 HMLα, resulting in the nonmating phenotype of an a/α diploid. However, sir5-2/sir5-2 mata1/MATα diploids mate as α yet are capable of sporulation. The sir5-2 mutation is unlinked to sir1-1, yet the two mutations do not complement each other: mata1/MATα 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.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=1216283Documentos Relacionados
- Alpha mating type-specific expression of mutations leading to constitutive agglutinability in Saccharomyces cerevisiae.
- A Suppressor of Mating-Type Locus Mutations in SACCHAROMYCES CEREVISIAE: Evidence for and Identification of Cryptic Mating-Type Loci
- Dominant and semidominant mutations leading to thermosensitivity of ribonucleic acid biosynthesis in Saccharomyces cerevisiae.
- Expression of Radiation-Induced Mutations at the Arginine Permease (CAN1) Locus in SACCHAROMYCES CEREVISIAE
- Nonsense mutations in the can1 locus of Saccharomyces cerevisiae.
