The function of CALM2 (calmodulin 2, ENSG00000143933) is as follows. Calmodulin acts as part of a calcium signal transduction pathway by mediating the control of a large number of enzymes, ion channels, aquaporins and other proteins through calcium-binding (PubMed:16760425, PubMed:26969752, PubMed:27165696). Calcium-binding is required for the activation of calmodulin (PubMed:16760425, PubMed:26969752, PubMed:27165696, PubMed:35568036). Among the enzymes to be stimulated by the calmodulin-calcium complex are a number of protein kinases, such as myosin light-chain kinases and calmodulin- dependent protein kinase type II (CaMK2), and phosphatases (PubMed:16760425, PubMed:26969752, PubMed:27165696, PubMed:35568036). Together with CCP110 and centrin, is involved in a genetic pathway that regulates the centrosome cycle and progression through cytokinesis (PubMed:16760425). Mediates calcium-dependent inactivation of CACNA1C (PubMed:26969752). Positively regulates calcium-activated potassium channel activity of KCNN2 (PubMed:27165696). {ECO:0000269|PubMed:16760425, ECO:0000269|PubMed:26969752, ECO:0000269|PubMed:27165696, ECO:0000269|PubMed:35568036}. (Microbial infection) Required for C.violaceum CopC and S.flexneri OspC3 arginine ADP-riboxanase activity. {ECO:0000269|PubMed:35338844, ECO:0000269|PubMed:35446120, ECO:0000269|PubMed:36423631, ECO:0000269|PubMed:36624349}.