Ste5 RING-H2 domain: role in Ste4-promoted oligomerization for yeast pheromone signaling.
Ste5 is a scaffold for the mitogen-activated protein kinase (MAPK) cascade components in a yeast pheromone response pathway. Ste5 also associates with Ste4, the beta subunit of a heterotrimeric guanine nucleotide-binding protein, potentially linking receptor activation to stimulation of the MAPK cascade. A RING-H2 motif at the Ste5 amino terminus ... is apparently essential for function because Ste5(C177S) and Ste5(C177A C180A) mutants did not rescue the mating defect of a ste5Delta cell. In vitro Ste5(C177A C180A) bound each component of the MAPK cascade, but not Ste4. Unlike wild-type Ste5, the mutant did not appear to oligomerize; however, when fused to a heterologous dimerization domain (glutathione S-transferase), the chimeric protein restored mating in an ste5Delta cell and an ste4Delta ste5Delta double mutant. Thus, the RING-H2 domain mediates Ste4-Ste5 interaction, which is a prerequisite for Ste5-Ste5 self-association and signaling.
Mesh Terms:
Adaptor Proteins, Signal Transducing, Amino Acid Sequence, Binding Sites, Calcium-Calmodulin-Dependent Protein Kinases, Carrier Proteins, Dimerization, Fungal Proteins, GTP-Binding Protein beta Subunits, GTP-Binding Proteins, Genetic Complementation Test, Glutathione Transferase, Heterotrimeric GTP-Binding Proteins, Molecular Sequence Data, Peptides, Pheromones, Point Mutation, Polymers, Recombinant Fusion Proteins, Saccharomyces cerevisiae, Saccharomyces cerevisiae Proteins, Signal Transduction, Transformation, Genetic
Adaptor Proteins, Signal Transducing, Amino Acid Sequence, Binding Sites, Calcium-Calmodulin-Dependent Protein Kinases, Carrier Proteins, Dimerization, Fungal Proteins, GTP-Binding Protein beta Subunits, GTP-Binding Proteins, Genetic Complementation Test, Glutathione Transferase, Heterotrimeric GTP-Binding Proteins, Molecular Sequence Data, Peptides, Pheromones, Point Mutation, Polymers, Recombinant Fusion Proteins, Saccharomyces cerevisiae, Saccharomyces cerevisiae Proteins, Signal Transduction, Transformation, Genetic
Science
Date: Oct. 03, 1997
PubMed ID: 9311911
View in: Pubmed Google Scholar
Download Curated Data For This Publication
15225
Switch View:
- Interactions 6