title: Fc gamma receptor II stimulated formation of inositol phosphates in human platelets is blocked by tyrosine kinase inhibitors and associated with tyrosine phosphorylation of the receptor.
abstract: We report that activation of phospholipase C (PLC) by cross-linking of the platelet low-affinity Fc gamma receptor II (Fc gamma RII) is inhibited by two structurally distinct tyrosine kinase inhibitors, staurosporine and ST271. This contrasts with PLC activation induced by thrombin and U46619, a thromboxane mimetic, whose receptors have seven transmembrane domains characteristic of G-protein coupled receptors. Several proteins undergo phosphorylation on tyrosine on Fc gamma RII cross-linking upstream of protein kinase C (PKC), Ca2+ and aggregation, including the Fc gamma RII itself. The role of Fc gamma RII phosphorylation in the regulation of PLC is discussed.
authors.affiliation: Department of Biochemistry, University of Dundee, Scotland.
authors.forename: R A
authors.initials: RA
authors.lastname: Blake
authors.forename: J
authors.initials: J
authors.lastname: Asselin
authors.forename: T
authors.initials: T
authors.lastname: Walker
authors.forename: S P
authors.initials: SP
authors.lastname: Watson
mesh_terms: D019796:15-Hydroxy-11 alpha,9 alpha-(epoxymethano)prosta-5,13-dienoic Acid; D000470:Alkaloids / Q000494:pharmacology; D001792:Blood Platelets / Q000378:metabolism*; D004533:Egtazic Acid / Q000031:analogs & derivatives / Q000494:pharmacology; D006801:Humans; D007211:Indoles / Q000494:pharmacology; D007295:Inositol Phosphates / Q000097:blood*; D010766:Phosphorylation; D011450:Prostaglandin Endoperoxides, Synthetic / Q000494:pharmacology; D011493:Protein Kinase C / Q000037:antagonists & inhibitors; D011505:Protein-Tyrosine Kinases / Q000037:antagonists & inhibitors*; D017452:Receptors, IgG / Q000378:metabolism*; D019311:Staurosporine; D013343:Styrenes / Q000494:pharmacology; D013917:Thrombin / Q000494:pharmacology; D013928:Thromboxane A2 / Q000031:analogs & derivatives / Q000494:pharmacology; D010738:Type C Phospholipases / Q000378:metabolism*; D014443:Tyrosine / Q000378:metabolism*
chemical_list: D000470:Alkaloids; D007211:Indoles; D007295:Inositol Phosphates; D011450:Prostaglandin Endoperoxides, Synthetic; D017452:Receptors, IgG; D013343:Styrenes; C086531:ST 271; C070379:1,2-bis(2-aminophenoxy)ethane N,N,N',N'-tetraacetic acid acetoxymethyl ester; D014443:Tyrosine; D004533:Egtazic Acid; D013928:Thromboxane A2; D019796:15-Hydroxy-11 alpha,9 alpha-(epoxymethano)prosta-5,13-dienoic Acid; D011505:Protein-Tyrosine Kinases; D011493:Protein Kinase C; D010738:Type C Phospholipases; D013917:Thrombin; D019311:Staurosporine; C064758:Ro 31-8220