Glycoproteins (chemical combinations of complex carbohydrate and protein) that form mucous gels coating the interior surfaces of the digestive tract. This gel acts to prevent digestion of the intestinal wall by digestive enzymes, water loss through the intestinal wall, bacteria from adhering to the intestinal cells, and toxins from being absorbed into the body, as well as facilitating the movement of food through the system. Mucins then are a first line of defence for all muscosal surfaces including not only the digestive system, but also the tear ducts and vocal apparatus. Mutations of mucins can serve as tumour markers for stomach, large bowel and laryngeal cancer.
See Cell adhesion molecules (CAMs), Carbohydrates, Cadherins, Enzyme, Glycoproteins, Integrins, Mutation (biology), Proteins, Selectins