The multifunctional CaMKII beta, or Ca2+/calmodulin-dependent protein kinase II, is a well known effector of calcium- and calmodulin- mediated functions. It is present in many tissues but is most abundant in the brain. CaMKII is composed of four different chains: alpha, beta, gamma, and delta. The different isoforms assemble into homo- or heteromultimeric holoenzymes composed of 8 to 12 subunits. Autophosphorylation plays an important role in the regulation of the kinase activity. CaMKII is r