Ligand-binding specificity of human fibroblast growth factor receptor-3 IIIc

Earlier studies indicated that human fibroblast growth factor receptor (FGFR)-3 me was activated equally well by both FGF-1 and FGF-2, In contrast, murine FGFR-3 IIIc was preferentially activated by FGF-1. To address this issue, we determined the ligand-binding specificity of human FGFR-3 IIIc in comparison with human FGFR-1 me. By equilibrium binding human FGFR-3 IIIc preferentially bound FGF-1 with high affinity, whereas FGFR-1 me bound both FGF-1 and -2 with high affinity, By competition binding using FGF-1, -2, -4, or 6, FGF-1 competed more efficiently than the other FGFs. These results suggest that like the murine FGFR-3 III, FGF-1 is a preferred ligand far human FGFR-3 IIIc. (C) 1997 Federation of European Biochemical Societies.