Mucin

Mucins (Mucin, MUC) are high molecular weight glycoproteins produced and secreted by epithelial cells, with mucus as their main component. Based on their functions, mucins can be divided into two categories: membrane-bound mucins and secreted mucins. Membrane-bound mucins include MUC1, MUC3A, MUC3B, MUC4, MUC12, MUC13, MUC14, MUC15, MUC16, MUC17, MUC20, MUC21, and MUC22, while secreted mucins include MUC2, MUC5AC, MUC5B, MUC6, MUC7, MUC8, MUC9, and MUC19. Abnormal mucin expression or function can lead to various diseases, including respiratory and gastrointestinal disorders, as well as certain types of cancer.