Specificity of fibrinogen and FGF-2 in promoting the association of FGFR1 with αvβ3. ECs were incubated with 10 μg/mL fibrinogen or 10 μg/mL vitronectin in the presence or absence of 100 ng/mL FGF-2 for 1 hour. Cells were then lysed and incubated with 5 μg/mL anti-αvβ3. Protein A–Sepharose beads were then added and incubated further for 30 minutes. Following washing, beads were boiled in electrophoresis diluent for 5 minutes and samples were electrophoresed on 10% gels. Western blotting (WB) was performed with anti-FGFR1. Lane 1, medium alone; lane 2, FGF-2; lane 3, fibrinogen; lane 4, FGF-2 plus fibrinogen; lane 5, vitronectin; lane 6, FGF-2 plus vitronectin; arrow indicates the location of FGFR1 (Mr ∼ 100 kDa). IP indicates immunopurification.
