rakuvälise maatriksi valk, millele kaudu saavad rakud maatriksile kinnituda ja sellele liikuda, 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.