The protein encoded by this gene is a membrane-bound mucin that provides protection to gut epithelial cells. The encoded protein contains about 60 tandem repeats, with each repeat being around 60 aa. N-glycosylation enables the encoded protein to localize on the cell surface, while the C-terminus interacts with the scaffold protein PDZ domain containing 1 (PDZK1). Two transcript variants, one protein-coding and the other non-protein coding, have been found for this gene. [provided by RefSeq, Nov 2015].