Fibronectin is a high-molecular weight (~440kDa) glycoprotein of the extracellular matrix that binds to membrane-spanning receptor proteins called integrins.

Similar to integrins, fibronectin binds extracellular matrix components such as collagen, fibrin, and heparan sulfate proteoglycans (e.g. syndecans).

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Alpha-5 beta-1 (α5β1), also known as the fibronectin receptor, is an integrin that binds to matrix macromolecules and proteinases and thereby stimulates angiogenesis.

It is composed of α5 (ITGA5/CD49e) and β1 (ITGB1/CD29) subunits. It is the primary receptor for fibronectin. The interaction of VLA-5 with fibronectin plays an important role in regulating inflammatory cytokine production by human articular chondrocytes (From the Cell Migration Gateway ITGA5 ITGB1).

α5β1-integrin is transported inside the cell by the kinesin KIF1C, a kinesin-3 organelle transporter that walks along microtubules.