The product of CAMK2B (calcium/calmodulin dependent protein kinase II beta) belongs to the serine/threonine protein kinase family and to the Ca (2+) /calmodulin-dependent protein kinase subfamily. Calcium signaling is crucial for several aspects of plasticity at glutamatergic synapses. In mammalian cells, the enzyme is composed of four different chains: alpha, beta, gamma, and delta. The product of CAMK2B is a beta chain. It is possible that distinct isoforms of this chain have different cellular localizations and interact differently with calmodulin. Alternative splicing results in multiple transcript variants.