Laminin structure

Laminin consists of three long polypeptides α, β, and γ; several types of each can combine to form many types of laminin. Disulfide bonds hold the polypeptides together in the shape of a cross. Laminins have several domains, including binding sites for components of the ECM proteins including type IV collagen and other accessory proteins and a distinct domain which enables binding to integrin receptors on cell surfaces. Since integrins are transmembrane receptors this association tethers the basal lamina to the cell membrane.