Modulator binding protein antagonizes activation of (Ca2+ + Mg2+)-ATPase and Ca2+ transport of red blood cell membranes.
Red blood cells contain a protein that activates membrane-bound (Ca2+ + Mg2+)-ATPase and Ca2+ transport. The red blood cell activator protein is similar to a modulator protein that stimulates cyclic AMP phosphodiesterase. Wang and Desai [Journal of Biological Chemistry 252:4175--4184, 1977] described a modulator-binding protein that antagonizes the activation of cyclic AMP phosphodiesterase by modulator protein. In the present work, modulator-binding protein was shown to antagonize the activation of (Ca2+ + Mg2+)-ATPase and Ca2+ transport by red blood cell activator protein. The results further demonstrate the similarity between the activator protein from human red blood cells and the modulator protein from bovine brain.
D001693:Biological Transport, Active / Q000187:drug effects; D002118:Calcium / Q000097:blood; D000252:Calcium-Transporting ATPases / Q000097:blood* / Q000378:metabolism; D002147:Calmodulin / Q000097:blood* / Q000494:pharmacology; D002352:Carrier Proteins / Q000097:blood*; D004789:Enzyme Activation / Q000187:drug effects; D004910:Erythrocyte Membrane / Q000201:enzymology*; D004912:Erythrocytes / Q000201:enzymology*; D006801:Humans
D002147:Calmodulin; D002352:Carrier Proteins; D000252:Calcium-Transporting ATPases; D002118:Calcium