This gene encodes an alpha integrin. Integrins are heterodimeric integral membrane glycoproteins composed of an alpha chain and a beta chain that mediate cell-cell and cell-matrix adhesion. The protein encoded by this gene, when bound to the beta 1 chain, forms an integrin that is a receptor for VCAM1, cytotactin and osteopontin. Expression of this gene has been found to be upregulated in small cell lung cancers. [provided by RefSeq, Jul 2008].