Ca2+/calmodulin-dependent protein kinase phosphatase (CaMKPase) is a protein phosphatase which dephosphorylates autophosphorylated Ca2+/calmodulin-dependent protein kinase II (CaMKII) and deactivates the enzyme (Ishida, A., Kameshita, I, and Fujisawa, H, (1998) J, Biol, Chem, 273, 1904-1910), In this study, a phosphorylation-dephosphorylation relationship between CaMKII and CaMKPase was examined. CaMKPase was not significantly phosphorylated by CaMKII under the standard phosphorylation conditions but was phosphorylated in the presence of poly-L-lysine, which is a potent activator of CaMKPase. The maximal extent of the phosphorylation was about 1 mol of phosphate per mol of the enzyme and the phosphorylation resulted in an about 2-fold increase in the enzyme activity. Thus, the activity of CaMKPase appears to be regulated through phosphorylation by its target enzyme, CaMKII, (C) 1999 Federation of European Biochemical Societies.
Isamu Kameshita, Atsuhiko Ishida, & Hitoshi Fujisawa. (1999). Phosphorylation and activation of Ca2+/calmodulin-dependent protein kinase phosphatase by Ca2+/calmodulin-dependent protein kinase II. FEBS Letters, 456(C), 249–252. https://doi.org/10.1016/0008-6215(87)80155-6