Title: | Functional and physical interactions among Saccharomyces cerevisiae alpha-factor receptors |
Author(s): | Gehret AU; Connelly SM; Dumont ME; |
Address: | "Department of Biochemistry and Biophysics, University of Rochester School of Medicine and Dentistry, Rochester, New York, USA" |
ISSN/ISBN: | 1535-9786 (Electronic) 1535-9778 (Print) 1535-9786 (Linking) |
Abstract: | "The alpha-factor receptor Ste2p is a G protein-coupled receptor (GPCR) expressed on the surface of MATa haploid cells of the yeast Saccharomyces cerevisiae. Binding of alpha-factor to Ste2p results in activation of a heterotrimeric G protein and of the pheromone response pathway. Functional interactions between alpha-factor receptors, such as dominant-negative effects and recessive behavior of constitutive and hypersensitive mutant receptors, have been reported previously. We show here that dominant-negative effects of mutant receptors persist over a wide range of ratios of the abundances of G protein to receptor and that such effects are not blocked by covalent fusion of G protein alpha subunits to normal receptors. In addition, we detected dominant effects of mutant C-terminally truncated receptors, which had not been previously reported to act in a dominant manner. Furthermore, coexpression of C-terminally truncated receptors with constitutively active mutant receptors results in enhancement of constitutive signaling. Together with previous evidence for oligomerization of Ste2p receptors, these results are consistent with the idea that functional interactions between coexpressed receptors arise from physical interactions between them rather than from competition for limiting downstream components, such as G proteins" |
Keywords: | "GTP-Binding Protein alpha Subunits/metabolism Genes, Dominant Genes, Recessive Mutation Protein Interaction Domains and Motifs Protein Multimerization Receptors, Mating Factor/chemistry/genetics/*metabolism Recombinant Fusion Proteins/genetics/metabolism;" |
Notes: | "MedlineGehret, Austin U Connelly, Sara M Dumont, Mark E eng R01 GM059357/GM/NIGMS NIH HHS/ R01 GM084083/GM/NIGMS NIH HHS/ GM59357/GM/NIGMS NIH HHS/ GM084083/GM/NIGMS NIH HHS/ Research Support, N.I.H., Extramural Research Support, Non-U.S. Gov't 2012/08/28 Eukaryot Cell. 2012 Oct; 11(10):1276-88. doi: 10.1128/EC.00172-12. Epub 2012 Aug 24" |