The protein kinase homologue Ste20p is required to link the yeast pheromone response G-protein beta gamma subunits to downstream signalling components

EMBO J. 1992 Dec;11(13):4815-24.


In the yeast Saccharomyces cerevisiae the G-protein beta gamma subunits have been shown to trigger downstream events of the pheromone response pathway. We have identified a new gene, designated STE20, which encodes a protein kinase homologue with sequence similarity to protein kinase C, which is required to transmit the pheromone signal from G beta gamma to downstream components of the signalling pathway. Overproduction of the kinase suppresses the mating defect of dominant-negative G beta mutations providing genetic evidence for an interaction with G beta, and epistasis experiments show that this kinase functions after or at the same point as G beta gamma, but before any of the other currently identified components of the signalling pathway. This points to a potentially new mechanism of G-protein mediated signal transduction, the activation of a protein kinase through G beta gamma.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Base Sequence
  • Blotting, Northern
  • Chromosome Mapping
  • DNA, Fungal / metabolism
  • Fungal Proteins / genetics
  • Fungal Proteins / metabolism*
  • GTP-Binding Proteins / metabolism*
  • Intracellular Signaling Peptides and Proteins
  • MAP Kinase Kinase Kinases
  • Molecular Sequence Data
  • Phenotype
  • Pheromones / metabolism*
  • Plasmids
  • Protein-Serine-Threonine Kinases / genetics
  • Protein-Serine-Threonine Kinases / metabolism*
  • RNA, Fungal / metabolism
  • Restriction Mapping
  • Saccharomyces cerevisiae / genetics
  • Saccharomyces cerevisiae / metabolism*
  • Saccharomyces cerevisiae Proteins*
  • Sequence Homology, Amino Acid
  • Signal Transduction*


  • DNA, Fungal
  • Fungal Proteins
  • Intracellular Signaling Peptides and Proteins
  • Pheromones
  • RNA, Fungal
  • Saccharomyces cerevisiae Proteins
  • Protein-Serine-Threonine Kinases
  • MAP Kinase Kinase Kinases
  • STE20 protein, S cerevisiae
  • GTP-Binding Proteins

Associated data

  • GENBANK/M94719
  • GENBANK/M94779
  • GENBANK/M94780
  • GENBANK/M94781
  • GENBANK/M94782
  • GENBANK/M94783
  • GENBANK/M94784
  • GENBANK/M94785
  • GENBANK/X67816
  • GENBANK/X67817