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PubMed · 2068102

Phosphatidate-dependent protein phosphorylation.

S B Bocckino·P B Wilson·J H Exton
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Abstract

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).

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Adenosine TriphosphateAnimalsBrainCytosolElectrophoresis, Polyacrylamide GelKineticsLiverLungMaleMolecular WeightMyocardiumOrgan SpecificityPhosphatidic AcidsPhosphoproteinsPhosphorylationProteinsRatsRats, Inbred StrainsTestisJournal ArticleResearch Support, U.S. Gov't, P.H.S.

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S B Bocckino, P B Wilson, J H Exton. 1991-07-15. Phosphatidate-dependent protein phosphorylation.. https://doi.org/10.1073/pnas.88.14.6210

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