alternative products: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,disease:Defects in ITGA6 are a cause of epidermolysis bullosa with pyloric atresia (EB-PA) [MIM:226730]; also known as aplasia cutis congenita with gastrointestinal atresia. EB-PA is an autosomal recessive disease characterized by mucocutaneous fragility and gastrointestinal atresia, which most commonly affects the pylorus.,function:Integrin alpha-6/beta-1 is a receptor for laminin on platelets. Integrin alpha-6/beta-4 is a receptor for laminin in epithelial cells and it plays a critical structural role in the hemidesmosome.,PTM: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.,similarity:Belongs to the integrin alpha chain family.,similarity:Contains 7 FG-GAP repeats.,subunit:Heterodimer of an alpha and a beta subunit. The alpha subunit is composed of an heavy and a light chain linked by a disulfide bond. Alpha-6 associates with either beta-1 or beta-4. Interacts with HPS5. Interacts with RAB21.,tissue specificity: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).,