FGF-9

FGF-9, originally purified as glia-activating factor from rat brain conditioned medium, binds FGFR2c and FGFR3c with preference and is expressed in brain, lung, gonad and synovium. In the developing lung it promotes mesenchymal proliferation and branching morphogenesis; in the gonad it supports testis cord formation; and in the adult joint it contributes to synovial inflammation in rheumatoid arthritis. FGF9 is upregulated in lung adenocarcinoma and in endometriotic lesions. Its survival-promoting action on dopaminergic and motor neurons makes it a candidate neuroprotective factor. Recombinant FGF-9 is used in these disease models and for FGFR3c-selective signaling studies.