partial proteolysis by trypsin and the effect of 20 microm la2+ on the formation of phosphoproteins before and after trypsinization support the conclusion that the 135 kda protein can be identified with the plasma membrane calcium pump , whereas the 115 kda phosphoprotein is the phosphorylated intermediate of a different type of calcium pump probably originating from the endoplasmic reticulum .
C0300252
plasma membrane calcium pump
C0001476
calcium pump