Title: | Two types of alpha-factor receptor determinants for pheromone specificity in the mating-incompatible yeasts S. cerevisiae and S. kluyveri |
Address: | "Department of Cell Biology, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, NY 10461, USA" |
ISSN/ISBN: | 0172-8083 (Print) 0172-8083 (Linking) |
Abstract: | "The specificity of mating-pheromone systems helps prevent mating between different species of yeast. The mechanism of specificity of G protein-coupled receptors in other organisms may be similar. To determine the structural basis of species discrimination between alpha-factor variants, small extracellular segments of the Saccharomyces cerevisiae alpha-factor receptor were substituted with residues from the Saccharomyces kluyveri alpha-factor receptor. Three substitutions altered specificity towards S. cerevisiae and S. kluyveri alpha-factor pheromone peptides. A substitution at residues 47-49 affected specificity for pheromone binding but not for pheromone activation of response. Substitution of residues 267-269 affected pheromone specificity for activation of cellular responses, but not for pheromone binding (under the assay conditions used). Substitution of residues 104-123 modestly affected both types of specificity. These results suggest two distinct types of receptor/ligand specificity (perhaps corresponding to ligand binding to G protein-coupled or uncoupled conformational states of the receptor) that evolved independently as S. cerevisiae and S. kluyveri diverged as species" |
Keywords: | "Binding Sites Fungal Proteins/*metabolism Mating Factor Peptides/metabolism Receptors, Mating Factor Receptors, Peptide/*metabolism Recombinant Fusion Proteins/metabolism Saccharomyces/*chemistry/classification Saccharomyces cerevisiae/*chemistry Species;" |
Notes: | "MedlineSen, M Shah, A Marsh, L eng GM43365/GM/NIGMS NIH HHS/ P30 CA13330/CA/NCI NIH HHS/ Comparative Study Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, P.H.S. 1997/03/01 Curr Genet. 1997 Mar; 31(3):235-40. doi: 10.1007/s002940050200" |