Title: | Cell cycle-dependent phosphorylation and ubiquitination of a G protein alpha subunit |
Author(s): | Torres MP; Clement ST; Cappell SD; Dohlman HG; |
Address: | "Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599-7260, USA" |
ISSN/ISBN: | 1083-351X (Electronic) 0021-9258 (Print) 0021-9258 (Linking) |
Abstract: | "A diverse array of external stimuli, including most hormones and neurotransmitters, bind to cell surface receptors that activate G proteins. Mating pheromones in yeast Saccharomyces cerevisiae activate G protein-coupled receptors and initiate events leading to cell cycle arrest in G(1) phase. Here, we show that the Galpha subunit (Gpa1) is phosphorylated and ubiquitinated in response to changes in the cell cycle. We systematically screened 109 gene deletion strains representing the non-essential yeast kinome and identified a single kinase gene, ELM1, as necessary and sufficient for Gpa1 phosphorylation. Elm1 is expressed in a cell cycle-dependent manner, primarily at S and G(2)/M. Accordingly, phosphorylation of Gpa1 in G(2)/M phase leads to polyubiquitination in G(1) phase. These findings demonstrate that Gpa1 is dynamically regulated. More broadly, they reveal how G proteins can simultaneously regulate, and become regulated by, progression through the cell cycle" |
Keywords: | "Cell Cycle/*physiology GTP-Binding Protein alpha Subunits, Gq-G11/genetics/*metabolism Phosphorylation/physiology Protein Kinases/genetics/*metabolism Saccharomyces cerevisiae/*enzymology/genetics Saccharomyces cerevisiae Proteins/genetics/*metabolism Ubi;" |
Notes: | "MedlineTorres, Matthew P Clement, Sarah T Cappell, Steven D Dohlman, Henrik G eng R01 GM080739/GM/NIGMS NIH HHS/ R01 GM059167/GM/NIGMS NIH HHS/ K99 GM094533-01/GM/NIGMS NIH HHS/ K99 GM094533/GM/NIGMS NIH HHS/ R01GM080739-S1/GM/NIGMS NIH HHS/ Research Support, N.I.H., Extramural 2011/04/28 J Biol Chem. 2011 Jun 10; 286(23):20208-16. doi: 10.1074/jbc.M111.239343. Epub 2011 Apr 26" |