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Updated: Jul 17, 2026
05:39
Determination of the Mating Efficiency of Haploids in Saccharomyces cerevisiae
Published on: December 2, 2022
Two Different h Mating Types in SCHIZOSACCHAROMYCES POMBE.
1Institute for Molecular Biology, The University of Texas at Dallas, Dallas, Texas 75230.
Genetics
|August 1, 1973
Summary
Two mating types exist in Schizosaccharomyces pombe: a stable heterothallic (h(-S)) and an unstable heterothallic (h(-U)) type. The unstable type can mutate, prompting a revision of the established two-gene mating type scheme.
Area of Science:
- * Yeast genetics
- * Molecular biology
- * Evolutionary genetics
Background:
- * The fission yeast Schizosaccharomyces pombe is a model organism in genetic research.
- * Leupold's work established heterothallic and homothallic mating types in S. pombe.
- * Mating type determination in S. pombe involves two closely linked genes.
Purpose of the Study:
- * To identify and characterize distinct heterothallic mating types in Schizosaccharomyces pombe.
- * To investigate the mutational behavior of these mating types.
- * To propose an updated genetic model for mating type determination.
Main Methods:
- * Genetic analysis of Schizosaccharomyces pombe strains.
- * Observation and documentation of mating type stability and mutation.
- * Comparative analysis with existing genetic models.
Main Results:
- * Identification of two distinct heterothallic mating types: stable (h(-S)) and unstable (h(-U)).
- * Demonstration that the unstable h(-U) mating type can mutate to heterothallic (+) and homothallic states.
- * Evidence supporting the instability and mutability of a specific heterothallic mating type.
Conclusions:
- * The discovery of the unstable h(-U) mating type necessitates a re-evaluation of S. pombe mating type genetics.
- * A revised two-gene scheme incorporating the h(-U) mating type is proposed.
- * This finding has implications for understanding mating system evolution in yeasts.
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