FGF8 Active Protein

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 is known to be a factor that supports androgen and anchorage independent growth of mammary tumor cells. Overexpression of this gene has been shown to increase tumor growth and angiogensis. The adult expression of this gene is restricted to testes and ovaries. Temporal and spatial pattern of this gene expression suggests its function as an embryonic epithelial factor. Studies of the mouse and chick homologs revealed roles in midbrain and limb development, organogenesis, embryo gastrulation and left-right axis determination. The alternative splicing of this gene results in four transcript variants. [provided by RefSeq, Jul 2008]

FGF8: Plays an important role in the regulation of embryonic development, cell proliferation, cell differentiation and cell migration. Required for normal brain, eye, ear and limb development during embryogenesis. Required for normal development of the gonadotropin-releasing hormone (GnRH) neuronal system. Defects in FGF8 are the cause of Kallmann syndrome type 6 (KAL6). Kallmann syndrome is a disorder that associates hypogonadotropic hypogonadism and anosmia. Anosmia or hyposmia is related to the absence or hypoplasia of the olfactory bulbs and tracts. Hypogonadism is due to deficiency in gonadotropin-releasing hormone and probably results from a failure of embryonic migration of gonadotropin-releasing hormone- synthesizing neurons. In some patients other developmental anomalies can be present, which include renal agenesis, cleft lip and/or palate, selective tooth agenesis, and bimanual synkinesis. In some cases anosmia may be absent or inconspicuous. Defects in FGF8 are a cause of idiopathic hypogonadotropic hypogonadism (IHH). IHH is defined as a deficiency of the pituitary secretion of follicle-stimulating hormone and luteinizing hormone, which results in the impairment of pubertal maturation and of reproductive function. Belongs to the heparin-binding growth factors family. 4 isoforms of the human protein are produced by alternative splicing.

Protein type: Cytokine; Secreted, signal peptide; Secreted

Chromosomal Location of Human Ortholog: 10q24

Cellular Component: extracellular space; extracellular region; external side of plasma membrane

Molecular Function: growth factor activity; type 2 fibroblast growth factor receptor binding; type 1 fibroblast growth factor receptor binding; chemoattractant activity; fibroblast growth factor receptor binding

Biological Process: gonad development; nerve growth factor receptor signaling pathway; apoptosis; cell proliferation in forebrain; adrenocorticotropin hormone secreting cell differentiation; thyroid stimulating hormone secreting cell differentiation; motor axon guidance; gastrulation; forebrain dorsal/ventral pattern formation; Wnt receptor signaling pathway through beta-catenin; mesodermal cell migration; embryonic hindlimb morphogenesis; response to organic cyclic substance; odontogenesis; BMP signaling pathway; positive chemotaxis; induction of an organ; positive regulation of cell proliferation; male genitalia development; thyroid gland development; pallium development; mesonephros development; heart looping; negative regulation of neuron apoptosis; otic vesicle formation; regulation of odontogenesis of dentine-containing teeth; epidermal growth factor receptor signaling pathway; response to drug; negative regulation of cardiac muscle development; anatomical structure morphogenesis; pharyngeal system development; fibroblast growth factor receptor signaling pathway; phosphoinositide-mediated signaling; positive regulation of mitosis; neural plate morphogenesis; MAPKKK cascade; subpallium development; forebrain morphogenesis; dorsal/ventral axon guidance; positive regulation of organ growth; patterning of blood vessels; forebrain neuron development; ureteric bud branching; midbrain-hindbrain boundary development; insulin receptor signaling pathway; innate immune response; blood vessel remodeling; response to oxidative stress; metanephros development

Disease: Hypogonadotropic Hypogonadism 6 With Or Without Anosmia