(Ca2+ + Mg2+)-ATPase activator: its presence in human red blood cells and rabbit skeletal muscle.
We find that both human red blood cells and rabbit skeletal muscle contain a soluble activator which can stimulate (Ca2+ + Mg2+)-ATPase activity. The activator protein from either source can enhance the (Ca2+ + Mg2+)-ATPase of both the red blood cell membrane and the microsomal fraction from skeletal muscle. The data suggest that they are members of the class of Ca2+-binding modulator proteins. A possible physiological role for the skeletal muscle activator protein in the contractile process is discussed.
D000818:Animals; D000252:Calcium-Transporting ATPases / Q000097:blood / Q000378:metabolism*; D002462:Cell Membrane / Q000201:enzymology; D004789:Enzyme Activation; D004912:Erythrocytes; D006801:Humans; D008274:Magnesium / Q000494:pharmacology*; D009132:Muscles / Q000201:enzymology; D011506:Proteins / Q000302:isolation & purification / Q000494:pharmacology*; D011817:Rabbits
D011506:Proteins; D000252:Calcium-Transporting ATPases; D008274:Magnesium