MUC1 is a glycoprotein that has large O-linked glycosylation in its extracellular region. Mucins line the apical layer of epithelial cells within the stomach, lungs, eyes, intestines, and a variety of other organs. You can know more about anti-MUC1 antibody picoband via Bosterbio.
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Mucins shield the body from infections by binding pathogens to oligosaccharides that are located in the extracellular region, stopping pathogens from reaching the cell's surface.
MUC1 belongs to the mucin family. It encodes glycosylated, membrane-bound proteins. MUC1's protein has a central mass of 120-225 kDa that can increase to 250-500kDa through glycosylation. It extends from 200-500nm to the cell's surface.
The protein is fixed to the apical layer of many epithelia through transmembrane-like domains. Beyond the transmembrane is the SEA domain which has an area for cleavage to release the vast extracellular domain.
The release of mucins can be carried out by sheddases. The extracellular domain contains an amino acid VNTR (VNTR) domain with repeated repeats that range between 20 and 120 in various individuals. They are rich in serine, threonine, and proline residues that allow the use of o-glycosylation in a large amount.
MUC1 is cut within the endoplasmic-reticulum into two parts, the cytoplasmic tail, which includes the transmembrane and extracellular domain.
The domains are closely linked in a non-covalent way. This non-covalent, tight association cannot be broken by treatment with urea in the low-pH range, high salt, or boiling. Treating sodium dodecyl sulfate causes dissociation of the subunits.
The cell's cytoplasmic tail of MUC1 has a length of 72 amino acids and has many phosphorylation locations.