Plays an important role in the regulation of cell proliferation and cell differentiation. Required for normal regulation of the hair growth cycle. Functions as an inhibitor of hair elongation by promoting progression from anagen, the growth phase of the hair follicle, into catagen the apoptosis-induced regression phase (By similarity). Interacts with FGFR1 and FGFR2. Affinity between fibroblast growth factors (FGFs) and their receptors is increased by heparan sulfate glycosaminoglycans that function as coreceptors. Expressed in neonatal brain. Can transform NIH 3T3 cells. The disease is caused by variants affecting the gene represented in this entry. Seems to have an antagonistic effect compared to that of the isoform Long. Belongs to the heparin-binding growth factors family.