title: Stimulation of the 23-Kd protein cAMP dependent phosphorylation by inositol 1,4,5 trisphosphate in human platelet membrane vesicles.
abstract: The effect of inositol 1,4,5 trisphosphate (IP3) has been investigated on the cAMP-induced phosphorylation of the 23-Kd protein involved in platelet calcium fluxes by isolated membrane vesicles. The studies were conducted using the catalytic subunit of the cAMP-dependent protein kinase (C. Sub.). A dose-dependent stimulation of the 23 Kd protein phosphorylation induced by C. Sub. was initiated by IP3 with a half-maximal effect of 0.5 microM. The maximal effect was observed after 1-2 min. The effect was detected in the absence of Ca2+ and in the presence of phosphatase inhibitors. These results can suggest that the 23 Kd is an associated protein to the IP3 receptor in human platelets.
mesh_terms: D001792:Blood Platelets / Q000378:metabolism*; D002462:Cell Membrane / Q000378:metabolism; D006801:Humans; D015544:Inositol 1,4,5-Trisphosphate; D007295:Inositol Phosphates / Q000097:blood*; D007700:Kinetics; D046911:Macromolecular Substances; D008565:Membrane Proteins / Q000097:blood*; D008970:Molecular Weight; D010766:Phosphorylation; D011494:Protein Kinases / Q000097:blood*; D013403:Sugar Phosphates / Q000097:blood*
chemical_list: D007295:Inositol Phosphates; D046911:Macromolecular Substances; D008565:Membrane Proteins; D013403:Sugar Phosphates; D015544:Inositol 1,4,5-Trisphosphate; D011494:Protein Kinases