Fibronectin (FN1) Human Active Protein

This gene encodes fibronectin, a glycoprotein present in a soluble dimeric form in plasma, and in a dimeric or multimeric form at the cell surface and in extracellular matrix. The encoded preproprotein is proteolytically processed to generate the mature protein. Fibronectin is involved in cell adhesion and migration processes including embryogenesis, wound healing, blood coagulation, host defense, and metastasis. The gene has three regions subject to alternative splicing, with the potential to produce 20 different transcript variants, at least one of which encodes an isoform that undergoes proteolytic processing. The full-length nature of some variants has not been determined. [provided by RefSeq, Jan 2016]

FN1: Fibronectins bind cell surfaces and various compounds including collagen, fibrin, heparin, DNA, and actin. Fibronectins are involved in cell adhesion, cell motility, opsonization, wound healing, and maintenance of cell shape. Defects in FN1 are the cause of glomerulopathy with fibronectin deposits type 2 (GFND2); also known as familial glomerular nephritis with fibronectin deposits or fibronectin glomerulopathy. GFND is a genetically heterogeneous autosomal dominant disorder characterized clinically by proteinuria, microscopic hematuria, and hypertension that leads to end-stage renal failure in the second to fifth decade of life. 15 isoforms of the human protein are produced by alternative splicing.

Protein type: Secreted; Secreted, signal peptide; Motility/polarity/chemotaxis; Cell adhesion

Chromosomal Location of Human Ortholog: 2q34

Cellular Component: extracellular matrix; extracellular space; apical plasma membrane; fibrinogen complex; extracellular region; ER-Golgi intermediate compartment; basal lamina

Molecular Function: heparin binding; collagen binding; integrin binding; protein binding; protease activator activity; protease binding

Biological Process: integrin activation; platelet activation; extracellular matrix organization and biogenesis; positive regulation of axon extension; extracellular matrix disassembly; regulation of cell shape; platelet degranulation; acute-phase response; calcium-independent cell-matrix adhesion; cell-substrate junction assembly; response to wounding; peptide cross-linking; angiogenesis; cell adhesion; blood coagulation; leukocyte migration

Disease: Glomerulopathy With Fibronectin Deposits 2; Plasma Fibronectin Deficiency