Phosphatidate-dependent protein phosphorylation.
Phosphatidate-dependent protein phosphorylation was observed in soluble extracts from rat liver, brain, lung, and testis. The phosphorylation was stimulated by free Ca2+ in the range of 360-800 nM. Incubation mixtures containing phosphatidate provided markedly different profiles of protein phosphorylation from those with phosphatidylserine plus 1,2-diolein. Phosphatidate-dependent phosphorylation of a 30-kDa protein in the soluble fraction from heart was also observed. This phosphorylation did not require Ca2+. Soluble fractions from liver, testis, brain, and lung phosphorylated the 30-kDa heart protein in a phosphatidate-dependent Ca(2+)-independent manner. We propose that part of the action of phosphatidate in cells may be mediated by a protein kinase(s).
Bocckino
S B
SB
Howard Hughes Medical Institute Laboratory, Vanderbilt University School of Medicine, Nashville, TN 37232-0295.
Wilson
P B
PB
Exton
J H
JH
D000255:Adenosine Triphosphate / Q000378:metabolism; D000818:Animals; D001921:Brain / Q000378:metabolism*; D003600:Cytosol / Q000378:metabolism; D004591:Electrophoresis, Polyacrylamide Gel; D007700:Kinetics; D008099:Liver / Q000378:metabolism*; D008168:Lung / Q000378:metabolism*; D008297:Male; D008970:Molecular Weight; D009206:Myocardium / Q000378:metabolism; D009928:Organ Specificity; D010712:Phosphatidic Acids / Q000494:pharmacology*; D010750:Phosphoproteins / Q000302:isolation & purification; D010766:Phosphorylation; D011506:Proteins / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains; D013737:Testis / Q000378:metabolism*
D010712:Phosphatidic Acids; D010750:Phosphoproteins; D011506:Proteins; D000255:Adenosine Triphosphate