Integrin alpha-6/beta-1 (ITGA6:ITGB1) is a receptor for laminin on platelets (By similarity). Integrin alpha-6/beta-1 (ITGA6:ITGB1) is present in oocytes and is involved in sperm-egg fusion (By similarity). Integrin alpha-6/beta-4 (ITGA6:ITGB4) is a receptor for laminin in epithelial cells and it plays a critical structural role in the hemidesmosome (By similarity). ITGA6:ITGB4 binds to NRG1 (via EGF domain) and this binding is essential for NRG1-ERBB signaling (PubMed:20682778). ITGA6:ITGB4 binds to IGF1 and this binding is essential for IGF1 signaling (PubMed:22351760). ITGA6:ITGB4 binds to IGF2 and this binding is essential for IGF2 signaling (PubMed:28873464). Heterodimer of an alpha and a beta subunit. The alpha subunit is composed of a heavy and a light chain linked by a disulfide bond (By similarity). Alpha-6 associates with either beta-1 (ITGB1) or beta-4 (ITGB4) to form ITGA6:ITGB1 and ITGA6:ITGB4, respectively (By similarity). ITGA6:ITGB1 is found in a complex with CD9; interaction takes place in oocytes and is involved in sperm-egg fusion (By similarity). ITGA6:ITGB4 is found in a ternary complex with NRG1 and ERBB3 (PubMed:20682778). ITGA6:ITGB4 is found in a ternary complex with IGF1 and IGF1R (PubMed:22351760). ITGA6:ITGB4 interacts with IGF2 (PubMed:28873464). Interacts with ADAM9 (By similarity). Interacts with RAB21 (PubMed:16754960). Interacts with MDK (PubMed:15466886). ITGA6:ITGB1 interacts with MDK; this interaction mediates MDK-induced neurite outgrowth (PubMed:15466886). Additional isoforms seem to exist. There is a combination of at least four alternatively spliced domains, two extracellular (X1 and X2) and two cytoplasmic (A and B). So far detected are isoform Alpha-6X1A, isoform Alpha-6X1B and isoform Alpha-6X1X2A (minor). Experimental confirmation may be lacking for some isoforms. Integrin alpha-6/beta-4 is predominantly expressed by epithelia. Isoforms containing segment X1 are ubiquitously expressed. Isoforms containing segment X1X2 are expressed in heart, kidney, placenta, colon, duodenum, myoblasts and myotubes, and in a limited number of cell lines; they are always coexpressed with the ubiquitous isoform containing segment X1. In some tissues (e.g. Salivary gland), isoforms containing cytoplasmic segment A and isoforms containing segment B are detected while in others, only isoforms containing one cytoplasmic segment are found (segment A in epidermis and segment B in kidney). Processed integrin alpha-6: Expressed at low levels in normal prostate tissue with elevated levels in prostate cancer tissue (at protein level) (PubMed:15023541). Isoforms containing segment A, but not segment B, are the major targets for PMA-induced phosphorylation. Phosphorylation occurs on 'Ser-1103' of isoform alpha-6X1X2A. Phosphorylation is not required for the induction of integrin alpha-6A/beta-1 high affinity but may reduce the affinity for ligand. Undergoes PLAU-mediated cleavage at residues Arg-634-635-Arg in a time-dependent manner to produce processed integrin alpha-6 (alpha6p) (PubMed:11359780, PubMed:15023541, PubMed:17303120). Production of alpha6p enhances prostate cancer cell invasion and migration (PubMed:17303120). Palmitoylation by DHHC3 enhances stability and cell surface expression. The disease is caused by variants affecting the gene represented in this entry. Belongs to the integrin alpha chain family. Truncated N-terminus.