TableEdit

Apone, F, Alyeshmerni, N, Wiens, K, Chalmers, D, Chrispeels, MJ and Colucci, G (2003) The G-protein-coupled receptor GCR1 regulates DNA synthesis through activation of phosphatidylinositol-specific phospholipase C. Plant Physiol. 133:571-9

Different lines of evidence suggest that specific events during the cell cycle may be mediated by a heterotrimeric G-protein activated by a cognate G-protein coupled receptor. However, coupling between the only known Galpha-subunit of the heterotrimeric G-protein (GPA1) and the only putative G-protein coupled receptor (GCR1) of plants has never been shown. Using a variety of approaches, we show here that GCR1-enhanced thymidine incorporation into DNA depends on an increase in phosphatidylinositol-specific phospholipase C activity and an elevation of inositol 1,4,5-trisphosphate levels in the cells. Tobacco (Nicotiana tabacum) cells that overexpress either Arabidopsis GCR1 or GPA1 display this phenomenon. We suggest on the basis of these results that GCR1-controlled events during the cell cycle involve phosphatidylinositol-specific phospholipase C as an effector of GCR1 and inositol 1,4,5-trisphosphate as a second messenger, and that GCR1 and GPA1 are both involved in this particular signaling pathway.

PubMed PMC219033 Online version:10.1104/pp.103.026005

Arabidopsis Proteins/metabolism; Cloning, Molecular; DNA Replication/genetics; DNA, Plant/biosynthesis; Enzyme Activation; Enzyme Inhibitors/pharmacology; Estrenes/pharmacology; Inositol 1,4,5-Trisphosphate/metabolism; Models, Biological; Phosphatidylinositol Diacylglycerol-Lyase/antagonists & inhibitors; Phosphatidylinositol Diacylglycerol-Lyase/metabolism; Phosphoinositide Phospholipase C; Phosphorylation; Protein Kinase C/metabolism; Pyrrolidinones/pharmacology; Receptors, G-Protein-Coupled/metabolism; Recombinant Proteins/metabolism; Signal Transduction; Thymidine/metabolism; Tobacco/metabolism; Transcription Factors/metabolism