Integrins are heterodimeric proteins made up of alpha and beta subunits. At least 18 alpha and 8 beta subunits have been described in mammals. Integrin family members are membrane receptors involved in cell adhesion and recognition in a variety of processes including embryogenesis, hemostasis, tissue repair, immune response and metastatic diffusion of tumor cells. Integrin alpha 5 belongs to the integrin alpha chain family. It contains seven FG-GAP repeats. Integrin beta 1 belongs to the integrin beta chain family. It contains one VWFA domain. Integrin alpha-5/beta-1 is a receptor for fibronectin and fibrinogen. It recognizes the sequence R-G-D in its ligands. In case of HIV-1 infection, the interaction with extracellular viral Tat protein seems to enhance angiogenesis in Kaposi's sarcoma lesions.

Integrin alpha 5: Membrane; Single-pass type I membrane protein. Integrin beta 1: Cell membrane; Single-pass type I membrane protein. Melanosome.