Laminins are heterotrimeric, noncollagenous glycoproteins composed of alpha, beta, and gamma chains. Through interactions with integrins, dystroglycan and other receptors, laminins contribute to cell differentiation, cell shape and migration, and maintenance of tissue phenotypes and survival. Laminin alpha 3/Laminin-5, also known as epiligrin, includes alpha 3, beta 3, and gamma 2 subunits. It is abundant in transitional epithelium, stratified squamous epithelia, lung mucosa and other epithelial glands and contributes to initiation and maintenance of epithelial cell anchorage to the underlying connective tissue. Within aa 21?1713 of the alpha 3 subunit, human and mouse share 77% amino acid sequence identity.