Nucleolin binds to FGF1 and FGF2.

<p>A) Proteins from cleared cell lysates (BJ or NIH3T3 cells) were pulled down by SBP-FGF1, Biot-FGF2, His-FGF1, GST-FGF1, GST-FGF2, GST protein, or no protein (–), and respective resins (Streptavidin-coated Dynabeads, Ni-NTA Superflow or Glutathione Sepharose™ 4 Fast Flow). Protein complexes were subjected to SDS-PAGE and immunoblotting (IB) with an anti-nucleolin antibody. B) HEK 293 cells transiently transfected with myc-FGF1 were lysed and then subjected to immunoprecipitation followed by SDS-PAGE and immunoblotting (IB) with an anti-nucleolin antibody. Non-transfected cells were used as controls. C) Recombinant nucleolin-C was incubated with recombinant SBP-FGF1 or Biot-FGF2 and Streptavidin-coated Dynabeads, then washed and analyzed by IB with an anti-nucleolin antibody. D) SPR analysis was performed using nucleolin-C immobilized on a CM4 sensor chip at the level of ∼540 RU and recombinant FGF1 or FGF2 were injected as analyte on the chip at increasing concentrations (10 nM to 320 nM) in duplicates (solid lines). Running buffer was injected in duplicates as a control (dashed lines). E) Interaction Maps from kinetic SPR data obtained for FGF1 and FGF2 binding to nucleolin-C. The contribution of a particular k_a or k_d in the overall binding event is shown by colors, from black (no contribution) to red (strong contribution).