| Title: | Ste5 RING-H2 domain: role in Ste4-promoted oligomerization for yeast pheromone signaling |
| Author(s): | Inouye C; Dhillon N; Thorner J; |
| Address: | "Department of Molecular and Cell Biology, Division of Biochemistry and Molecular Biology, University of California, Berkeley, CA 94720-3202, USA" |
| DOI: | 10.1126/science.278.5335.103 |
| ISSN/ISBN: | 0036-8075 (Print) 0036-8075 (Linking) |
| Abstract: | "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" |
| Keywords: | "*Adaptor Proteins, Signal Transducing Amino Acid Sequence Binding Sites Calcium-Calmodulin-Dependent Protein Kinases/metabolism *Carrier Proteins Dimerization Fungal Proteins/*chemistry/genetics/*metabolism *GTP-Binding Protein beta Subunits GTP-Binding P;" |
| Notes: | "MedlineInouye, C Dhillon, N Thorner, J eng CA09041/CA/NCI NIH HHS/ GM21841/GM/NIGMS NIH HHS/ Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, P.H.S. 1997/10/06 Science. 1997 Oct 3; 278(5335):103-6. doi: 10.1126/science.278.5335.103" |
