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Genetic Screen for Identification of Multicopy Suppressors in Schizosaccharomyces pombe
13:22

Genetic Screen for Identification of Multicopy Suppressors in Schizosaccharomyces pombe

Published on: September 13, 2022

A novel gene, msa1, inhibits sexual differentiation in Schizosaccharomyces pombe

Hee Tae Jeong1, Fumiyo Ozoe, Katsunori Tanaka

  • 1Department of Life Science and Biotechnology, Faculty of Life and Environmental Science, Shimane University, Matsue 690-8504, Japan.

Genetics
|May 29, 2004
PubMed

Insights

A novel gene, msa1, inhibits sexual differentiation in fission yeast by negatively regulating key genes. Its disruption leads to hypersporulation, suggesting a crucial role in controlling yeast reproductive processes.

Area of Science:

  • Molecular Biology
  • Yeast Genetics
  • Cellular Differentiation

Background:

  • Sexual differentiation in fission yeast (Schizosaccharomyces pombe) is a complex process initiated by nutrient starvation or mating pheromones.
  • Understanding the regulatory mechanisms governing this transition is crucial for comprehending yeast development and reproduction.

Purpose of the Study:

  • To identify and characterize novel genes involved in the regulation of sexual differentiation in Schizosaccharomyces pombe.
  • To elucidate the function of the newly identified gene, msa1, in controlling sexual differentiation.

Main Methods:

  • Gene disruption and overexpression in Schizosaccharomyces pombe.
  • Genetic analysis involving deletion mutants (ras1, rad24, msa2/nrd1) and phenotypic assessment.
  • Analysis of gene expression for pheromone-induced genes (mei2, mam2, ste11, rep1).

Main Results:

  • A novel gene, msa1, encoding a putative RNA-binding protein, was identified as an inhibitor of sexual differentiation.
  • Disruption of msa1 resulted in hypersporulation, while its expression diminished under nitrogen starvation.
  • Msa1 function is independent of cAMP and stress pathways; it negatively regulates Ste11-regulated genes, potentially via the pheromone-signaling pathway, and interacts with Ras1 and other regulatory proteins.

Conclusions:

  • Msa1 acts as a key negative regulator of sexual differentiation in fission yeast.
  • The Msa1 protein likely controls sexual differentiation by modulating the expression of genes within the Ste11 regulatory network, possibly through the pheromone-signaling pathway.

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