Mucin-15 is a single-pass type I membrane protein member of the Mucin family. Mucins are a family of high molecular weight, heavily glycosylated proteins (glycoconjugates) produced by epithelial tissues in most metazoans. A key characteristic of Mucins is their ability to form gels. Therefore they are a key component in most gel-like secretions, serving functions from lubrication to cell signalling to forming chemical barriers. Mucin-15 is expressed in many tissues. Mucin-15 is highly glycosylated (N- and O-linked carbohydrates). Mucin-15 may play a role in the cell adhesion to the extracellular matrix.