title: The effect of protein kinase C activation on G(z)-mediated regulation of type 2 and 6 adenylyl cyclases.
abstract: Three serine-to-alanine mutants of the alpha subunit of the heterotrimeric G protein G(z) (alpha(z)) were examined for their signaling properties in the presence of phorbol ester treatment. All three alpha(z) mutants resembled wild-type alpha(z) in their abilities to inhibit alpha(s)-stimulated type 6 adenylyl cyclase (AC6) and phorbol ester treatment reduced their magnitudes of inhibition. Depending on the permissive condition, the betagamma-mediated stimulation of type 2 adenylyl cyclase (AC2) was differentially regulated by alpha(z) and the three mutants. Mutation of Ser(27) but not Ser(16) of alpha(z) affected the efficient release of betagamma subunits upon receptor activation and abolished the stimulation of phosphorylated but not alpha(s)-stimulated AC2.
authors.affiliation: Department of Biology and Biotechnology Research Institute, Hong Kong University of Science and Technology, Hong Kong, China.
authors.forename: M K
authors.initials: MK
authors.lastname: Ho
authors.forename: J S
authors.initials: JS
authors.lastname: Chan
authors.forename: L Y
authors.initials: LY
authors.lastname: Yung
authors.forename: Y H
authors.initials: YH
authors.lastname: Wong
mesh_terms: D037361:Adenylate Cyclase Toxin; D000067956:Adenylyl Cyclase Inhibitors; D000262:Adenylyl Cyclases / Q000145:classification / Q000378:metabolism*; D001665:Binding Sites / Q000235:genetics; D002460:Cell Line; D004789:Enzyme Activation / Q000187:drug effects; D044385:GTP-Binding Protein alpha Subunits; D020962:Heterotrimeric GTP-Binding Proteins / Q000235:genetics / Q000378:metabolism* / Q000494:pharmacology; D006801:Humans; D010766:Phosphorylation; D017354:Point Mutation; D011493:Protein Kinase C / Q000378:metabolism*; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism / Q000494:pharmacology; D015398:Signal Transduction; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D014162:Transfection; D010566:Virulence Factors, Bordetella / Q000494:pharmacology
chemical_list: D037361:Adenylate Cyclase Toxin; D000067956:Adenylyl Cyclase Inhibitors; C099387:GNAZ protein, human; D044385:GTP-Binding Protein alpha Subunits; D011994:Recombinant Proteins; D010566:Virulence Factors, Bordetella; D011493:Protein Kinase C; D020962:Heterotrimeric GTP-Binding Proteins; D000262:Adenylyl Cyclases; D013755:Tetradecanoylphorbol Acetate