Phosphorylation of type II (beta) protein kinase C by casein kinase II.
Rat brain type II (beta) protein kinase C (PKC) was phosphorylated by rat lung casein kinase II (CK-II). Neither type I (gamma) nor type III (alpha) PKC was significantly phosphorylated by CK-II. CK-II incorporated 0.2-0.3 mol of phosphate into 1 mol of type II PKC. This phosphate was located at the single seryl residue (Ser-11) in the V1-variable region of the regulatory domain of the PKC molecule. A glutamic acid cluster was located at the carboxyl-terminal side of Ser-11, showing the consensus sequence for phosphorylation by CK-II. The velocity of this phosphorylation was enhanced by the addition of Ca2+, diolein, and phosphatidylserine, which are all required for the activation of PKC. Phosphorylation of casein or synthetic oligopeptides by CK-II was not affected by Ca2+, diolein, or phosphatidylserine. Available evidence suggests that CK-II phosphorylates preferentially the activated form of type II PKC. It remains unknown, however, whether this reaction has a physiological significance.
Tominaga
M
M
Department of Biochemistry, Kobe University School of Medicine, Hyogo.
Kitagawa
Y
Y
Tanaka
S
S
Kishimoto
A
A
D000595:Amino Acid Sequence; D000818:Animals; D001921:Brain / Q000201:enzymology; D047388:Casein Kinases; D006493:Heparin / Q000494:pharmacology; D007527:Isoenzymes / Q000302:isolation & purification / Q000378:metabolism*; D007700:Kinetics; D008168:Lung / Q000201:enzymology; D008969:Molecular Sequence Data; D008970:Molecular Weight; D010748:Phosphopeptides / Q000302:isolation & purification; D010766:Phosphorylation; D011107:Polylysine / Q000494:pharmacology; D011493:Protein Kinase C / Q000302:isolation & purification / Q000378:metabolism*; D011494:Protein Kinases / Q000378:metabolism*; D051381:Rats
D007527:Isoenzymes; D010748:Phosphopeptides; D011107:Polylysine; D006493:Heparin; D011494:Protein Kinases; D047388:Casein Kinases; D011493:Protein Kinase C