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. Activates MPK8 through direct binding and in an calcium-dependent manner. Interacts with KCBP. Interacts with MPK8 in an calcium-dependent manner. A number of isoforms are produced. According to EST sequences. This protein has four functional calcium-binding sites. Belongs to the calmodulin family.