title: Contribution of Src and Ras pathways in FGF-2 induced endothelial cell differentiation.
abstract: We have examined fibroblast growth factor (FGF) receptor-1 mediated signal transduction in differentiation of endothelial cells (EC). The activated FGFR-1 couples to Ras through two adaptor proteins, FRS2 and Shc. In FGF-2 treated proliferating EC, FRS2 as well as Shc are tyrosine phosphorylated and interact with Grb2. In contrast, in FGF-2 treated differentiating cells, Shc, but not FRS2, is engaged in Grb2-interactions. Sustained MAP kinase activity has previously been implicated in differentiation. In FGF stimulated proliferating and differentiating endothelial cells, the MAP kinase Erk2 is activated in a sustained manner. Inhibition of MEK and MAP kinase activity by PD98059 treatment of cells, still allows EC tube formation. The FGFR-1 mediates activation of protein kinase C (PKC) through direct binding and activation of phospholipase C-gamma (PLC-gamma), and has also been shown to activate the cytoplasmic tyrosine kinase Src. Treatment of the cells with the PKC inhibitor bisindolylmaleimide does not prevent tube formation. In contrast, Src kinase activity is a prerequisite for EC differentiation, since treatment of the cells with PP1, a Src family specific inhibitor, abrogates tube formation. In differentiating EC, FGF-2 induces complex formation between Src and focal adhesion kinase (FAK). These data indicate that the Ras pathway is initiated via Shc or FRS2, dependent on the cellular program. Blocking the function of Src family kinases, attenuates differentiation.
authors.affiliation: Department of Medical Biochemistry and Microbiology, BMC, Uppsala, Sweden.
authors.forename: P
authors.initials: P
authors.lastname: Klint
authors.forename: S
authors.initials: S
authors.lastname: Kanda
authors.forename: Y
authors.initials: Y
authors.lastname: Kloog
authors.forename: L
authors.initials: L
authors.lastname: Claesson-Welsh
mesh_terms: D048868:Adaptor Proteins, Signal Transducing; D000818:Animals; D000077214:Becaplermin; D017871:Calcium-Calmodulin-Dependent Protein Kinases / Q000187:drug effects / Q000378:metabolism; D015815:Cell Adhesion Molecules / Q000187:drug effects / Q000378:metabolism; D002454:Cell Differentiation / Q000187:drug effects / Q000502:physiology; D002455:Cell Division / Q000502:physiology; D002460:Cell Line; D004730:Endothelium, Vascular / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D004791:Enzyme Inhibitors / Q000494:pharmacology; D016222:Fibroblast Growth Factor 2 / Q000378:metabolism* / Q000494:pharmacology; D005419:Flavonoids / Q000494:pharmacology; D051417:Focal Adhesion Kinase 1; D051416:Focal Adhesion Protein-Tyrosine Kinases; D051380:GRB2 Adaptor Protein; D011905:Genes, ras; D007211:Indoles / Q000494:pharmacology; D007527:Isoenzymes / Q000187:drug effects / Q000378:metabolism; D008301:Maleimides / Q000494:pharmacology; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism; D051379:Mice; D008822:Mice, Transgenic; D051966:Phospholipase C gamma; D010750:Phosphoproteins / Q000235:genetics / Q000378:metabolism; D010982:Platelet-Derived Growth Factor / Q000378:metabolism / Q000494:pharmacology; D011493:Protein Kinase C / Q000037:antagonists & inhibitors / Q000187:drug effects / Q000378:metabolism; D011505:Protein-Tyrosine Kinases / Q000187:drug effects / Q000378:metabolism; D011506:Proteins / Q000235:genetics / Q000378:metabolism; D020574:Proto-Oncogene Proteins c-sis; D020794:Receptor Protein-Tyrosine Kinases / Q000235:genetics / Q000378:metabolism; D051496:Receptor, Fibroblast Growth Factor, Type 1; D017468:Receptors, Fibroblast Growth Factor / Q000235:genetics / Q000378:metabolism; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism; D015398:Signal Transduction; D010738:Type C Phospholipases / Q000187:drug effects / Q000378:metabolism; D018631:ras Proteins / Q000235:genetics / Q000378:metabolism; D018909:src Homology Domains
chemical_list: D048868:Adaptor Proteins, Signal Transducing; D015815:Cell Adhesion Molecules; D004791:Enzyme Inhibitors; C106534:FRS2 protein, human; D005419:Flavonoids; D051380:GRB2 Adaptor Protein; C495949:Grb2 protein, mouse; D007211:Indoles; D007527:Isoenzymes; D008301:Maleimides; D008565:Membrane Proteins; D010750:Phosphoproteins; D010982:Platelet-Derived Growth Factor; D011506:Proteins; D020574:Proto-Oncogene Proteins c-sis; D017468:Receptors, Fibroblast Growth Factor; D011994:Recombinant Proteins; D016222:Fibroblast Growth Factor 2; D000077214:Becaplermin; C496349:Fgfr1 protein, mouse; D011505:Protein-Tyrosine Kinases; D020794:Receptor Protein-Tyrosine Kinases; D051496:Receptor, Fibroblast Growth Factor, Type 1; D051417:Focal Adhesion Kinase 1; D051416:Focal Adhesion Protein-Tyrosine Kinases; C496051:Ptk2 protein, mouse; D011493:Protein Kinase C; D017871:Calcium-Calmodulin-Dependent Protein Kinases; D010738:Type C Phospholipases; D051966:Phospholipase C gamma; D018631:ras Proteins; C070515:bisindolylmaleimide I; C093973:2-(2-amino-3-methoxyphenyl)-4H-1-benzopyran-4-one