Phosphorylation of lipocortins in vitro by protein kinase C.
Protein kinase C catalyzes the incorporation of about 1.1, 0.7 and 0.4 mole of phosphate per mole of Lipocortin-I (P35), Lipocortin-II (P36) and Lipocortin-85 (P36 oligomer) respectively. The phosphorylation is specific for protein kinase C and is dependent on the presence of both calcium and phospholipids. While Lipocortin-I is phosphorylated on threonine residues, Lipocortin-II and Lipocortin-85 are phosphorylated on serine residues. The substoichiometric phosphorylation of Lipocortin-85 appears to preclude the potential regulation of this protein by protein kinase C. The phosphorylation of Lipocortin-I on threonine residues and Lipocortin-II on serine residues suggests these proteins may be regulated by distinct phosphorylation-dephosphorylation reactions.
D000818:Animals; D017302:Annexins; D002417:Cattle; D006023:Glycoproteins / Q000302:isolation & purification / Q000378:metabolism*; D066298:In Vitro Techniques; D007700:Kinetics; D008168:Lung / Q000378:metabolism; D010750:Phosphoproteins / Q000378:metabolism*; D010766:Phosphorylation; D011493:Protein Kinase C / Q000378:metabolism*; D011494:Protein Kinases / Q000378:metabolism; D013379:Substrate Specificity
D017302:Annexins; D006023:Glycoproteins; D010750:Phosphoproteins; D011494:Protein Kinases; D011493:Protein Kinase C