Cyclic GMP regulation of the plasma membrane (Ca2+-Mg2+)ATPase in vascular smooth muscle.
Plasma membrane (Ca2+-Mg2+)ATPase purified from bovine aortic microsomes by calmodulin affinity chromatography was incorporated into soybean phospholipid liposomes. In the reconstituted proteoliposomes, a protein corresponding to the ATPase was phosphorylated by [gamma-32P]ATP in the presence of cGMP and cGMP-dependent protein kinase. Both the affinity for Ca2+ and the maximum Ca2+ uptake activity by the proteoliposomes were increased by the cGMP-dependent phosphorylation, and there was good parallelism between the Ca2+-uptake rate and the extent of phosphorylation. These results strongly suggest that the Ca2+-transport ATPase of the vascular smooth muscle plasma membrane is regulated through its cGMP-dependent phosphorylation.
D000818:Animals; D001013:Aorta, Thoracic / Q000201:enzymology; D017301:Ca(2+) Mg(2+)-ATPase / Q000378:metabolism*; D000252:Calcium-Transporting ATPases / Q000378:metabolism*; D002417:Cattle; D002462:Cell Membrane / Q000201:enzymology*; D006152:Cyclic GMP / Q000378:metabolism / Q000502:physiology*; D066298:In Vitro Techniques; D007700:Kinetics; D008861:Microsomes / Q000201:enzymology; D009131:Muscle, Smooth, Vascular / Q000201:enzymology*; D010766:Phosphorylation
D017301:Ca(2+) Mg(2+)-ATPase; D000252:Calcium-Transporting ATPases; D006152:Cyclic GMP