αv β3 and αv β5

Integrins are heterodimeric cell surface receptors composed of non-covalently associated transmembrane glycoproteins, a and b, which connect adhesive proteins in the extracellular matrix to the cytoskeleton. Integrins not only mediate attachment of cells to their substratum, but are also involved in intracellular signal transduction. Excluding splice variants, at present 16 different α- and 8 different β-subunits have been identified which associate to form more than 20 receptors each recognizing one or more extracellular ligands.