Mucin-6 (MUC6)

Mucin-6 (MUC6) is a high-molecular-weight, gel-forming glycoprotein primarily expressed in the mucous neck cells of the gastric body and the pyloric glands of the antrum (UniProt P35080). It is a major component of the gastric mucus layer, where it functions alongside MUC5AC to protect the stomach lining from the harsh acidic environment and digestive enzymes (NCBI Gene: 4588). A distinctive feature of MUC6 is its unique O-glycosylation, specifically the presence of terminal alpha-1,4-linked N-acetylglucosamine residues, which act as a natural antibiotic against Helicobacter pylori by inhibiting the synthesis of its cell wall (Kawakubo et al., Science, 2004). In clinical contexts, MUC6 is often used as a biomarker; its expression is frequently downregulated in gastric carcinomas but can be aberrantly expressed in other conditions like pancreatic mucinous cystic neoplasms (Ho et al., Cancer Research, 1995). Research into MUC6 focuses on its protective role in the gut and its potential as a target for glycan-mimetic therapies or diagnostic imaging in oncology.

Other names

Gastric mucin-6MUC-6Secreted gel-forming mucin 6

MUC6 acts as a physical barrier and a biochemical inhibitor of bacterial growth; specifically, its terminal alpha-1,4-GlcNAc residues inhibit the biosynthesis of cholesteryl-alpha-D-glucopyranoside in H. pylori (Kawakubo et al., Science, 2004).