CaMKPase is a member of the PP2C family of Ser/Thr protein phosphatases that dephosphorylate and regulate the multifunctional Ca2+/calmodulin-dependent protein kinases (CaMKs). The multifunctional CaMKs mediate cellular responses induced by increases in second messenger Ca2+ and have been implicated in the control of synaptic transmission, gene transcription, cell growth and contraction of cardiac and smooth muscles. Overexpression of CaMKPase has been shown to mediate caspase-dependent apoptosis. CaMKPase can also interact with the Rho guanine nucleotide exchange factors (PIX) thereby blocking the effects of p21-activated kinase 1 (PAK1).