| Title: | Mutations affecting ligand specificity of the G-protein-coupled receptor for the Saccharomyces cerevisiae tridecapeptide pheromone |
| Author(s): | Abel MG; Lee BK; Naider F; Becker JM; |
| Address: | "Department of Microbiology, University of Tennessee, Knoxville, TN 37996, USA" |
| DOI: | 10.1016/s0167-4889(98)00109-8 |
| ISSN/ISBN: | 0006-3002 (Print) 0006-3002 (Linking) |
| Abstract: | "Random mutations were generated in the G-protein-coupled receptor (Ste2p) for the tridecapeptide pheromone (alpha-factor) of Saccharomyces cerevisiae. These mutants were screened for variants that responded to antagonists. Because multiple mutations were detected in each mutant receptor recovered from the screen, site-directed mutagenesis was used to create single-site mutant receptors. Three receptors containing mutations F55V, S219P, and S259P were analyzed for their biological responses to various alpha-factor analogs and for their ligand binding profiles. Cells expressing each of the mutant receptors responded to alpha-factor as well as or better than wild-type cells in a growth arrest assay. In contrast, the binding of alpha-factor to the F55V and S219P mutant receptors was at least 10-fold reduced in comparison to wild-type receptor indicating a complex non-linear correlation between binding affinity and biological activity. Cells expressing mutant receptors responded to some normally inactive analogs in biological assays, despite the fact that these analogs had a low affinity for Ste2p. The analysis of these mutant receptors confirms previous findings that the first and sixth transmembrane regions of Ste2p are important for ligand interaction, ligand specificity, and/or receptor activation to initiate the signal transduction pathway. Changes in binding affinity of pheromone analogs to wild-type and mutant receptors indicate that residue 55 of Ste2p is involved with both ligand binding and signal transduction" |
| Keywords: | "Binding Sites Binding, Competitive Dose-Response Relationship, Drug GTP-Binding Proteins/*metabolism Mating Factor Mutagenesis Peptides/chemistry/*metabolism Pheromones/*metabolism Protein Binding Receptors, Mating Factor Receptors, Peptide/agonists/antag;" |
| Notes: | "MedlineAbel, M G Lee, B K Naider, F Becker, J M eng GM-22086/GM/NIGMS NIH HHS/ GM-22087/GM/NIGMS NIH HHS/ Research Support, U.S. Gov't, P.H.S. Netherlands 1998/11/24 Biochim Biophys Acta. 1998 Nov 19; 1448(1):12-26. doi: 10.1016/s0167-4889(98)00109-8" |
