Interactions of pure beta gamma-subunits of G-proteins with purified beta 1-adrenoceptor.
The role of the beta gamma-subunits in the interaction of G-proteins was examined with beta 1-adrenoceptors purified from turkey erythrocytes and pure beta gamma-subunits prepared from turkey erythrocytes and bovine brain. On a non-denaturing polyacrylamide gel, the mobility of beta gamma-subunits was increased when incubated with beta 1-adrenoceptor and the beta 1-adrenergic agonist 1-(-)-isoproterenol, whereas on incubation with the antagonist 1-alprenolol the mobility was unchanged. Furthermore, the beta 1-adrenoceptor was retarded on a Sephadex G-50 column equilibrated with beta gamma-subunits and agonist. No retardation occurred in the presence of antagonist. These data suggest a direct interaction of activated beta 1-adrenoceptors with isolated beta gamma-subunits of G-proteins.
Im
M J
MJ
Department of Physiological Chemistry, University of Würzburg, Medical School, FRG.
Holzhöfer
A
A
Böttinger
H
H
Pfeuffer
T
T
Helmreich
E J
EJ
D000818:Animals; D001921:Brain / Q000378:metabolism*; D002417:Cattle; D004591:Electrophoresis, Polyacrylamide Gel; D004910:Erythrocyte Membrane / Q000378:metabolism*; D019204:GTP-Binding Proteins / Q000378:metabolism*; D046911:Macromolecular Substances; D011943:Receptors, Adrenergic, beta / Q000302:isolation & purification / Q000378:metabolism*; D014422:Turkeys
D046911:Macromolecular Substances; D011943:Receptors, Adrenergic, beta; D019204:GTP-Binding Proteins