Calmodulin is a highly conserved regulatory protein found in all eukaryotic cells.This protein is involved in many cellular processes such as glycogen metabolism,cytoskeletal control, neurotransmission, phosphate activity and control of NAD₊/NADP₊ Calmodulin binds proteins principally through their interactions with hydrophobic sites on its surface. These sites are exposed after a conformational change induced by the action of Ca₂₊ on separate Ca₂₊-binding sites. The binding of enzymes may be enhanced if the enzyme substrate is present and enzyme-substratecalmoldulin-Ca₂₊ complexes are particularly stable