MUC16
This gene encodes a protein that is a member of the mucin family. Mucins are high molecular weight, O-glycosylated proteins that play an important role in forming a protective mucous barrier, and are found on the apical surfaces of the epithelia. The encoded protein is a membrane-tethered mucin that contains an extracellular domain at its amino terminus, a large tandem repeat domain, and a transmembrane domain with a short cytoplasmic domain. The amino terminus is highly glycosylated, while the repeat region contains 156 amino acid repeats unit that are rich in serines, threonines, and prolines. Interspersed within the repeats are Sea urchin sperm protein Enterokinase and Agrin (SEA) modules, leucine-rich repeats and ankyrin (ANK) repeats. These regions together form the ectodomain, and there is a potential cleavage site found near an SEA module close to the transmembrane domain. This protein is thought to play a role in forming a barrier, protecting epithelial cells from pathogens. Products of this gene have been used as a marker for different cancers, with higher expression levels associated with poorer outcomes. [provided by RefSeq, May 2017]
Full Name
Mucin 16, Cell Surface Associated
Function
Thought to provide a protective, lubricating barrier against particles and infectious agents at mucosal surfaces.
Biological Process
Cell adhesion Source: UniProtKB
Cellular Location
Extracellular space
Plasma membrane
Cell membrane
Note: May be liberated into the extracellular space following the phosphorylation of the intracellular C-terminus which induces the proteolytic cleavage and liberation of the extracellular domain.
Topology
Extracellular: 1-14451
Helical: 14452-14472
Cytoplasmic: 14473-14507
PTM
Heavily O-glycosylated; expresses both type 1 and type 2 core glycans.
Heavily N-glycosylated; expresses primarily high mannose and complex bisecting type N-linked glycans.
May be phosphorylated. Phosphorylation of the intracellular C-terminal domain may induce proteolytic cleavage and the liberation of the extracellular domain into the extracellular space.
May contain numerous disulfide bridges. Association of several molecules of the secreted form may occur through interchain disulfide bridges providing an extraordinarily large gel-like matrix in the extracellular space or in the lumen of secretory ducts.