title: IL-2 binding activates a tyrosine-phosphorylated phosphatidylinositol-3-kinase.
abstract: IL-2 was shown to induce phosphatidylinositol-3-kinase activity in the CTLL-2 murine lymphocyte line. Tyrosine phosphorylation of phosphatidylinositol-3-kinase was demonstrated by immunoabsorption with antiphosphotyrosine antibody and was coincident with activation of an IL-2R-associated tyrosine kinase. Half-maximal activation of this enzyme, and of cell proliferation, occurred at 30 pM IL-2. Incubation of cells with genistein, a selective tyrosine kinase inhibitor, blocked IL-2-dependent activation of receptor-associated tyrosine kinase and phosphatidylinositol-3-kinase activities, suggesting that tyrosine phosphorylation-dependent activation of phosphatidylinositol-3-kinase is a component of the IL-2R signal transduction process.
authors.affiliation: Department of Pathology and Laboratory Medicine, University of Pennsylvania, School of Medicine, Philadelphia.
authors.forename: I
authors.initials: I
authors.lastname: Merida
authors.forename: E
authors.initials: E
authors.lastname: Diez
authors.forename: G N
authors.initials: GN
authors.lastname: Gaulton
mesh_terms: D019870:1-Phosphatidylinositol 4-Kinase; D000818:Animals; D002455:Cell Division; D004789:Enzyme Activation; D007376:Interleukin-2 / Q000378:metabolism / Q000494:pharmacology*; D051379:Mice; D010766:Phosphorylation; D010770:Phosphotransferases / Q000378:metabolism*; D011505:Protein-Tyrosine Kinases / Q000378:metabolism; D015375:Receptors, Interleukin-2 / Q000378:metabolism; D015398:Signal Transduction; D014443:Tyrosine / Q000378:metabolism*
chemical_list: D007376:Interleukin-2; D015375:Receptors, Interleukin-2; D014443:Tyrosine; D010770:Phosphotransferases; D019870:1-Phosphatidylinositol 4-Kinase; D011505:Protein-Tyrosine Kinases