Regulation of purified type I and type II adenylylcyclases by G protein beta gamma subunits.
Type I and type II adenylylcyclases have been purified after expression in Sf9 cells, each by application of a two-step purification protocol. The specific activities of the essentially homogeneous enzymes are approximately 7 and 2 mumol.min-1.mg-1, respectively. Each purified enzyme preparation is activated by Gs alpha, but they are regulated in an opposite fashion by G protein beta gamma subunits. Purified beta gamma inhibits Gs alpha-stimulated type I adenylylcyclase directly, while beta gamma activates type II adenylylcyclase and potentiates the Gs alpha-mediated stimulation of the enzyme. This is the first demonstration of the activation of a purified effector molecule by G protein beta gamma subunits.
Taussig
R
R
Department of Pharmacology, University of Texas Southwestern Medical Center, Dallas 75235.
Quarmby
L M
LM
Gilman
A G
AG
D000262:Adenylyl Cyclases / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D000595:Amino Acid Sequence; D000818:Animals; D016367:Baculoviridae / Q000235:genetics; D001483:Base Sequence; D001921:Brain / Q000378:metabolism; D002417:Cattle; D002460:Cell Line; D002462:Cell Membrane / Q000201:enzymology; D002852:Chromatography, Ion Exchange; D003001:Cloning, Molecular; D004591:Electrophoresis, Polyacrylamide Gel; D004789:Enzyme Activation; D019204:GTP-Binding Proteins / Q000378:metabolism*; D016244:Guanosine 5'-O-(3-Thiotriphosphate) / Q000494:pharmacology; D007313:Insecta; D007527:Isoenzymes / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D007700:Kinetics; D046911:Macromolecular Substances; D008969:Molecular Sequence Data; D008970:Molecular Weight; D009838:Oligodeoxyribonucleotides; D010957:Plasmids; D011994:Recombinant Proteins / Q000302:isolation & purification / Q000378:metabolism; D014162:Transfection
D007527:Isoenzymes; D046911:Macromolecular Substances; D009838:Oligodeoxyribonucleotides; D011994:Recombinant Proteins; D016244:Guanosine 5'-O-(3-Thiotriphosphate); D019204:GTP-Binding Proteins; D000262:Adenylyl Cyclases