From Wikipedia, the free encyclopedia
Jump to: navigation, search
Fibroblast growth factor 9
Protein FGF9 PDB 1g82.png
PDB rendering based on 1g82.
Available structures
PDB Ortholog search: PDBe, RCSB
Symbols FGF9 ; FGF-9; GAF; HBFG-9; HBGF-9; SYNS3
External IDs OMIM600921 MGI104723 HomoloGene1523 GeneCards: FGF9 Gene
RNA expression pattern
PBB GE FGF9 206404 at tn.png
More reference expression data
Species Human Mouse
Entrez 2254 14180
Ensembl ENSG00000102678 ENSMUSG00000021974
UniProt P31371 P54130
RefSeq (mRNA) NM_002010 NM_013518
RefSeq (protein) NP_002001 NP_038546
Location (UCSC) Chr 13:
22.25 – 22.28 Mb
Chr 14:
58.07 – 58.11 Mb
PubMed search [1] [2]

Glia-activating factor is a protein that in humans is encoded by the FGF9 gene.[1][2]

The protein encoded by this gene is a member of the fibroblast growth factor (FGF) family. FGF family members possess broad mitogenic and cell survival activities, and are involved in a variety of biological processes, including embryonic development, cell growth, morphogenesis, tissue repair, tumor growth and invasion. This protein was isolated as a secreted factor that exhibits a growth-stimulating effect on cultured glial cells. In nervous system, this protein is produced mainly by neurons and may be important for glial cell development. Expression of the mouse homolog of this gene was found to be dependent on Sonic hedgehog (Shh) signaling. Mice lacking the homolog gene displayed a male-to-female sex reversal phenotype, which suggested a role in testicular embryogenesis.[2]


FGF9 has been shown to interact with Fibroblast growth factor receptor 3.[3][4]

Role in sex determination[edit]

FGF9 has also been shown to play a vital role in male development. Once activated by SOX9, it is responsible for forming a feedforward loop with Sox9, increasing the levels of both genes. The absence of Fgf9 causes an individual, even an individual with X and Y chromosomes, to develop into a female, as it’s needed to carry out important masculinizing developmental functions such as the multiplication of Sertoli cells and creation of the testis cords.[5]


  1. ^ Miyamoto M, Naruo K, Seko C, Matsumoto S, Kondo T, Kurokawa T (Jul 1993). "Molecular cloning of a novel cytokine cDNA encoding the ninth member of the fibroblast growth factor family, which has a unique secretion property". Mol Cell Biol 13 (7): 4251–9. PMC 359975. PMID 8321227. 
  2. ^ a b "Entrez Gene: FGF9 fibroblast growth factor 9 (glia-activating factor)". 
  3. ^ Santos-Ocampo S, Colvin JS, Chellaiah A, Ornitz DM (January 1996). "Expression and biological activity of mouse fibroblast growth factor-9". J. Biol. Chem. 271 (3): 1726–31. doi:10.1074/jbc.271.3.1726. PMID 8576175. 
  4. ^ Chellaiah A, Yuan W, Chellaiah M, Ornitz DM (December 1999). "Mapping ligand binding domains in chimeric fibroblast growth factor receptor molecules. Multiple regions determine ligand binding specificity". J. Biol. Chem. 274 (49): 34785–94. doi:10.1074/jbc.274.49.34785. PMID 10574949. 
  5. ^ Kim Y, Kobayashi A, Sekido R, DiNapoli L, Brennan J, Chaboissier MC, Poulat F, Behringer RR, Lovell-Badge R, Capel B (June 2006). "Fgf9 and Wnt4 act as antagonistic signals to regulate mammalian sex determination". PLoS Biol. 4 (6): e187. doi:10.1371/journal.pbio.0040187. PMC 1463023. PMID 16700629. 

Further reading[edit]