Title: | Characterization of a novel mammalian RGS protein that binds to Galpha proteins and inhibits pheromone signaling in yeast |
Author(s): | Chen C; Zheng B; Han J; Lin SC; |
Address: | "Regulatory Biology Laboratory, Institute of Molecular and Cell Biology, National University of Singapore, 10 Kent Ridge Crescent, Singapore 119260, Republic of Singapore" |
ISSN/ISBN: | 0021-9258 (Print) 0021-9258 (Linking) |
Abstract: | "Genetic studies of molecules that negatively regulate G-coupled receptor functions have led to the identification of a large gene family with an evolutionarily conserved domain, termed the RGS domain. It is now understood that RGS proteins serve as GTPase-activating proteins for subfamilies of the heterotrimeric G-proteins. We have isolated from mouse pituitary a full-length cDNA clone encoding a novel member of the RGS protein family, termed RGS16, as well as the full-length cDNA of mRGS5 and mRGS2. Tissue distribution analysis shows that the novel RGS16 is predominantly expressed in liver and pituitary, and that RGS5 is preferentially expressed in heart and skeletal muscle. In contrast, RGS2 is widely expressed. Genetic analysis using the pheromone response halo assay and FUS1 gene induction assay show that overexpression of the RGS16 gene dramatically inhibits yeast response to alpha-factor, whereas neither RGS2 nor RGS5 has any discernible effect on pheromone sensitivity, pointing to a possible functional diversity among RGS proteins. In vitro binding assays reveal that RGS5 and RGS16 bind to Galphai and Galphao subunits of heterotrimeric G-proteins, but not to Galphas. Based on mutational analysis of the conserved residues in the RGS domain, we suggest that the G-protein binding and GTPase-activating protein activity may involve distinct functional structures of the RGS proteins, indicating that RGS proteins may exert a dual function in the attenuation of signaling via G-coupled receptors" |
Keywords: | Amino Acid Sequence Animals Caenorhabditis elegans Conserved Sequence Humans Mice Molecular Sequence Data Pheromones/*metabolism Phosphoproteins/*metabolism Pituitary Gland/chemistry Polymerase Chain Reaction Proteins/chemistry/*metabolism *RGS Proteins S; |
Notes: | "MedlineChen, C Zheng, B Han, J Lin, S C eng Research Support, Non-U.S. Gov't 1997/03/28 J Biol Chem. 1997 Mar 28; 272(13):8679-85. doi: 10.1074/jbc.272.13.8679" |