An epithelial mucin (MUC-1 glycoprotein) found on the surface of bladder epithelium and in the urine. Also found on the surface of some tumour cells (CA antigen). Like other mucins, it is a transmembrane protein with the extracellular N-terminal subunit having variable numbers of 20 aa tandem repeats that are extensively O-glycosylated. Probably normally exists as aggregates of three or four monomers, each of 350–400 kDa. See episialin.
Subjects: Medicine and Health.