ATP-binding on fibroblast growth factor 2 partially overlaps with the heparin-binding domain.
Fibroblast growth factor 2 (FGF2), an intensively studied heparin-binding cytokine, is an important modulator of cell growth and differentiation under both physiological and pathophysiological conditions. It has been shown recently that ATP binds to FGF2 and that this binding is crucial for its biological function. In this study we demonstrated that divalent cations were not necessary for binding of ATP to FGF2, but it could be demonstrated that heparin blocked the labelling of FGF2 with ATP indicating an involvement of the heparin-binding domain (aa 128-144) in ATP-binding. FGF2, bound to Heparin Sepharose, could be eluted with ATP and GTP, but not with cAMP, AMP or ADP. Successive mutation of positively charged amino acid residues located in the heparin-binding domain drastically reduced the signal intensity of [gamma-(32)P]ATP labelled FGF2 indicating that this domain is not only important for heparin binding to FGF2 but also for ATP-binding.
Institut für Pharmazeutische und Medizinische Chemie, Westfälische Wilhelms-Universität Münster, Hittorfstr. 58-62, 48149 Münster, Germany.
Karsten
K
Rose
Stefanie
S
Pallast
Susanne
S
Klumpp
Josef
J
Krieglstein
D000255:Adenosine Triphosphate / Q000737:chemistry*; D053477:Apoptotic Protease-Activating Factor 1 / Q000737:chemistry; D001665:Binding Sites; D002454:Cell Differentiation; D049109:Cell Proliferation; D002845:Chromatography / Q000379:methods; D016222:Fibroblast Growth Factor 2 / Q000737:chemistry*; D018841:HSP90 Heat-Shock Proteins / Q000737:chemistry; D006493:Heparin / Q000737:chemistry*; D006801:Humans; D015233:Models, Statistical; D016297:Mutagenesis, Site-Directed; D009154:Mutation; D011485:Protein Binding; D017434:Protein Structure, Tertiary
C506592:APAF1 protein, human; D053477:Apoptotic Protease-Activating Factor 1; D018841:HSP90 Heat-Shock Proteins; D016222:Fibroblast Growth Factor 2; D000255:Adenosine Triphosphate; D006493:Heparin