A novel Ca2+/calmodulin-dependent protein kinase lacking autophosphorylation activity in the rabbit heart.
We report the discovery, semi-purification and characterization of a novel Ca2+/calmodulin-dependent protein kinase (peak I kinase) using syntide 2 as a substrate from the rabbit heart. In the study of dependence of peak I kinase on the concentration of calmodulin, half-maximal activation was obtained at approx. 2.0 x 10(-7) M calmodulin. Peak I kinase did not undergo autophosphorylation. This kinase phosphorylates the synthetic peptides such as syntide 2, autocamtide-2, site 3 in a Ca2+/CaM-dependent manner, but not myosin light chain-peptide, gamma-peptide, and cAMP Response Element Binding Protein (CREB) peptide. Elongation Factor-2, alpha-casein and histone-IIIs were not phosphorylated. These data indicate that this CaM kinase is different from other identified Ca2+/calmodulin-dependent protein kinases and therefore constitutes a novel protein kinase.
Uemura
A
A
Department of Pharmacology, Nagoya University School of Medicine, Japan.
Okazaki
K
K
Takesue
H
H
Matsubara
T
T
Hidaka
H
H
D000818:Animals; D017871:Calcium-Calmodulin-Dependent Protein Kinases / Q000737:chemistry / Q000302:isolation & purification* / Q000378:metabolism*; D002147:Calmodulin / Q000494:pharmacology; D002846:Chromatography, Affinity; D002848:Chromatography, DEAE-Cellulose; D002850:Chromatography, Gel; D002852:Chromatography, Ion Exchange; D036341:Intercellular Signaling Peptides and Proteins; D008970:Molecular Weight; D009206:Myocardium / Q000201:enzymology*; D010455:Peptides / Q000378:metabolism; D010766:Phosphorylation; D011817:Rabbits; D013379:Substrate Specificity
D002147:Calmodulin; D036341:Intercellular Signaling Peptides and Proteins; D010455:Peptides; C063391:syntide-2; D017871:Calcium-Calmodulin-Dependent Protein Kinases