Calmodulin mediates the control of a large number of enzymes, ion channels and other proteins by Ca(2+). Among the enzymes to be stimulated by the calmodulin-Ca(2+) complex are a number of protein kinases and phosphatases. Two calmodulins are synthesized during differentiation of Naegleria gruberi from amoebae to flagellates; one remains in the cell body and the other becomes localized in the flagella. Flagellar calmodulin first appears during early stages of differentiation, is maximally expressed at the time that flagella first appear and then levels rapidly decline. This protein has four functional calcium-binding sites. Belongs to the calmodulin family.