Skip to main content
Genetics logoLink to Genetics
. 1977 Mar;85(3):395–405. doi: 10.1093/genetics/85.3.395

Interconversion of Yeast Mating Types III. Action of the Homothallism (HO) Gene in Cells Homozygous for the Mating Type Locus

James B Hicks 1, Jeffrey N Strathern 1, Ira Herskowitz 1
PMCID: PMC1224575  PMID: 17248736

Abstract

Mating type interconversion in homothallic Saccharomyces cerevisiae has been studied in diploids homozygous for the mating type locus produced by sporulation of a/a/a/α and a/a/α/α tetraploid strains. Mating type switches have been analyzed by techniques including direct observation of cells for changes in α-factor sensitivity. Another method of following mating type switching exploits the observation that a/α cells exhibit polar budding and a/a and α/α cells exhibit medial budding.—These studies indicate the following: (1) The allele conferring the homothallic life cycle (HO) is dominant to the allele conferring the heterothallic life cycle (ho). (2) The action of the HO gene is controlled by the mating type locus—active in a/a and α/α cells but not in a/α cells. (3) The HO (or HO-controlled) gene product can act independently on two mating type alleles located on separate chromosomes in the same nucleus. (4) A switch in mating type is observed in pairs of cells, each of which has the same change.

Full Text

The Full Text of this article is available as a PDF (1.0 MB).

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Hicks J. B., Herskowitz I. Interconversion of Yeast Mating Types II. Restoration of Mating Ability to Sterile Mutants in Homothallic and Heterothallic Strains. Genetics. 1977 Mar;85(3):373–393. doi: 10.1093/genetics/85.3.373b. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Roman H, Phillips M M, Sands S M. Studies of Polyploid Saccharomyces. I. Tetraploid Segregation. Genetics. 1955 Jul;40(4):546–561. doi: 10.1093/genetics/40.4.546. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Takano I., Oshima Y. An allele specific and a complementary determinant controlling homothallism in Saccharomyces oviformis. Genetics. 1967 Dec;57(4):875–885. doi: 10.1093/genetics/57.4.875. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Takano I., Oshima Y. Mutational nature of an allele-specific conversion of the mating type by the homothallic gene HO alpha in Saccharomyces. Genetics. 1970 Jul;65(3):421–427. doi: 10.1093/genetics/65.3.421. [DOI] [PMC free article] [PubMed] [Google Scholar]

Articles from Genetics are provided here courtesy of Oxford University Press

RESOURCES