Purification of three forms of lipocortin from bovine lung.
Experimental conditions are described for simultaneous purification of three forms of lipocortin (lipocortin I, lipocortin II and lipocortin-85) from bovine lung. The procedure yields milligram quantities of all three lipocortins. Using antisera against lipocortin I and lipocortin II, purified proteins show no cross contaminations. All forms of lipocortin exhibit equal potency as in vitro bovine pancreatic phospholipase A2 inhibitors. Protein kinase C catalyzes the in vivo incorporation of about 1.0, 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.
D000818:Animals; D017302:Annexins; D002417:Cattle; D002848:Chromatography, DEAE-Cellulose; D004533:Egtazic Acid; D004591:Electrophoresis, Polyacrylamide Gel; D006023:Glycoproteins / Q000302:isolation & purification*; D007120:Immunochemistry; D008168:Lung / Q000032:analysis*; D010740:Phospholipases / Q000037:antagonists & inhibitors*; D010741:Phospholipases A / Q000037:antagonists & inhibitors*; D054467:Phospholipases A2; D010766:Phosphorylation; D011493:Protein Kinase C / Q000378:metabolism
D017302:Annexins; D006023:Glycoproteins; D004533:Egtazic Acid; D011493:Protein Kinase C; D010740:Phospholipases; D010741:Phospholipases A; D054467:Phospholipases A2