Plays an important role in the regulation of embryonic development, cell proliferation, and cell differentiation. Required for normal limb and cardiac valve development during embryogenesis (By similarity). Interacts with FGFR1, FGFR2, FGFR3 and FGFR4. Affinity between fibroblast growth factors (FGFs) and their receptors is increased by heparan sulfate glycosaminoglycans that function as coreceptors (By similarity). Belongs to the heparin-binding growth factors family.