May have a role in glial cell growth and differentiation during development, gliosis during repair and regeneration of brain tissue after damage, differentiation and survival of neuronal cells, and growth stimulation of glial tumors.

Glial cells.

Defects in FGF9 are the cause of multiple synostoses syndrome type 3 (SYNS3) [MIM:612961]. Multiple synostoses syndrome is an autosomal dominant condition characterized by progressive joint fusions of the fingers, wrists, ankles and cervical spine, characteristic facies and progressive conductive deafness.

Belongs to the heparin-binding growth factors family.

Three molecular species were found (30 kDa, 29 kDa and 25 kDa), cleaved at Leu-4, Val-13 and Ser-34 respectively. The smaller ones might be products of proteolytic digestion. Furthermore, there may be a functional signal sequence in the 30 kDa species which is uncleavable in the secretion step.
N-glycosylated.

Secreted.