Concerted action of RAS and G proteins in the sexual response pathways of Schizosaccharomyces pombe

Hao Peng Xu, Michael White, Stevan Marcus, Michael Wigler

Research output: Contribution to journalArticle

58 Scopus citations


We have shown that the expression of mam2, the gene encoding the Schizosaccharomyces pombe P-factor pheromone receptor, is dependent upon components of the pheromone signal transduction pathway, including Ras1, Gpa1, Byr1 and Byr2, each of which is required for both conjugation and sporulation. Studies of the expression of mam2 in mutant S. pombe cells confirm previous conclusions, based on the ability of cells to sporulate, that the Byr1 protein kinase acts downstream of the Byr2 protein kinase and that both act downstream of Ras1, the S. pombe RAS homolog, and Gpa1, the G(α) component that mediates the occupancy of the mam2 receptor. In addition, our present studies show that Ras1 and Gpa1 each act downstream from the other and hence act in concert. The Spk1 kinase, which is required for conjugation and sporulation and which is a structural and functional homolog of the vertebrate MAP kinases, is not required for mam2 expression.

Original languageEnglish (US)
Pages (from-to)50-58
Number of pages9
JournalMolecular and cellular biology
Issue number1
StatePublished - Jan 1 1994


ASJC Scopus subject areas

  • Molecular Biology
  • Cell Biology

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