Calphobindin I (annexin V) inhibits protein kinase C.
We investigated the inhibitory effect of calphobindin I (CPB I) on protein kinase C activity. CPB I inhibited protein kinase C activity in a concentration-dependent manner with an IC50 value of 70 nM. The inhibition of protein kinase C by CPB I was Ca(2+)-dependent, and was partially overcome by increasing the concentration of phosphatidylserine. Since CPB I is widely distributed in various organs and cells, it is presumed that CPB I is an endogenous inhibitor of protein kinase C.
Shibata
S
S
Department of Obstetrics and Gynecology, Akita University School of Medicine.
Sato
H
H
Maki
M
M
D000818:Animals; D017304:Annexin A5; D001921:Brain / Q000201:enzymology; D002118:Calcium / Q000494:pharmacology; D002135:Calcium-Binding Proteins / Q000494:pharmacology*; D066298:In Vitro Techniques; D010718:Phosphatidylserines / Q000494:pharmacology; D011257:Pregnancy Proteins / Q000494:pharmacology*; D011493:Protein Kinase C / Q000037:antagonists & inhibitors*; D051381:Rats
D017304:Annexin A5; D002135:Calcium-Binding Proteins; D010718:Phosphatidylserines; D011257:Pregnancy Proteins; D011493:Protein Kinase C; D002118:Calcium