title: Cell signalling through guanine-nucleotide-binding regulatory proteins (G proteins) and phospholipases.
abstract: Phospholipases are important enzymes in cell signal transduction since they hydrolyze membrane phospholipids to generate signalling molecules. Heterotrimeric guanine-nucleotide-binding regulatory proteins (G proteins) play a major role in their regulation by a variety of agonists that activate receptors with seven membrane-spanning domains. Phospholipases of the C type, which hydrolyze inositol phospholipids to yield inositol trisphosphate and diacylglycerol, are regulated by the alpha and betagamma subunits of certain heterotrimeric G proteins as well as by receptor-associated and non-receptor-associated tyrosine kinases. Phospholipases of the D type, which hydrolyze phosphatidylcholine to phosphatidic acid, are regulated by members of the ADP-ribosylation factor and Rho subfamilies of small G proteins, and by protein kinase C and other factors. This review presents recent information concerning the molecular details of G protein regulation of these phospholipases.
authors.affiliation: Howard Hughes Medical Institute, Department of Molecular Physiology, Vanderbilt University School of Medicine, Nashville, TN 37295, USA.
authors.forename: J H
authors.initials: JH
authors.lastname: Exton
mesh_terms: D020727:ADP-Ribosylation Factors; D000818:Animals; D004789:Enzyme Activation; D019204:GTP-Binding Proteins / Q000502:physiology*; D006801:Humans; D007527:Isoenzymes / Q000502:physiology; D010740:Phospholipases / Q000502:physiology*; D011493:Protein Kinase C / Q000502:physiology; D011956:Receptors, Cell Surface / Q000502:physiology; D015398:Signal Transduction; D020744:rac GTP-Binding Proteins; D020741:rho GTP-Binding Proteins
chemical_list: D007527:Isoenzymes; D011956:Receptors, Cell Surface; D011493:Protein Kinase C; D010740:Phospholipases; D019204:GTP-Binding Proteins; D020727:ADP-Ribosylation Factors; D020744:rac GTP-Binding Proteins; D020741:rho GTP-Binding Proteins