Adhesive glycoproteins: Fibronectin

Fibronectins are a family of closely related glycoproteins in the ECM that help guide cell movement. Fibronectin has two large subunits linked near the C-terminals by two disulfide bonds. Each of the two Fibronectin subunits is folded into a series of rod-like domains which bind one or more ECM macromolecules, including several types of Collagen. Other domains of Fibronectin recognize cell surface receptors (Integrins) via a RGD (arg-gly-asp) sequence. This enables Fibronectin to act as a bridging molecule between cells and the ECM.