Family of integral membrane proteins which serve as receptors for fibronectin, laminin, and other adhesive extracellular glycoproteins.

Integrins are transmembrane glycoprotein receptors that mediate cell-matrix or cell-cell adhesion, and transduce signals that regulate gene expression and cell growth. They are heterodimeric molecules consisting of noncovalently linked alpha and beta subunits. Different combinations of alpha and beta polypeptides form complexes that vary in their ligand-binding specificities. Both alpha and beta subunits display a cytoplasmic domain that interacts with the cytoskeleton (and possibly signaling molecules), a transmembrane region, and a large extracellular domain that interacts with the extracellular matrix. (from OMIM 147557)

A family of transmembrane glycoproteins (MEMBRANE GLYCOPROTEINS) consisting of noncovalent heterodimers. They interact with a wide variety of ligands including EXTRACELLULAR MATRIX PROTEINS; COMPLEMENT, and other cells, while their intracellular domains interact with the CYTOSKELETON. The integrins consist of at least three identified families: the cytoadhesin receptors (RECEPTORS, CYTOADHESIN), the leukocyte adhesion receptors (RECEPTORS, LEUKOCYTE ADHESION), and the VERY LATE ANTIGEN RECEPTORS. Each family contains a common beta-subunit (INTEGRIN BETA CHAINS) combined with one or more distinct alpha-subunits (INTEGRIN ALPHA CHAINS). These receptors participate in cell-matrix and cell-cell adhesion in many physiologically important processes, including embryological development; HEMOSTASIS; THROMBOSIS; WOUND HEALING; immune and nonimmune defense mechanisms; and oncogenic transformation.