CA15-3
CA15-3 is the name commonly used for mucin-1 (MUC1, CD227), a membrane-bound, O-glycosylated mucin found on the apical surface of epithelial cells. It helps form protective mucous barriers and also takes part in intracellular signalling. Browse Assay Genie's current range of CA15-3 research reagents below, or read on for the biology behind the target.
CA15-3 corresponds to mucin-1, encoded by the MUC1 gene. Mucins are O-glycosylated proteins that form protective mucous barriers on epithelial surfaces, and mucin-1 is a membrane-bound member of the family. The protein is proteolytically cleaved into alpha and beta subunits that form a heterodimeric complex. The N-terminal alpha subunit functions in cell adhesion, while the C-terminal beta subunit is involved in cell signalling through phosphorylation and protein-protein interactions.
Through the beta subunit, mucin-1 modulates signalling in the ERK, SRC and NF-kappa-B pathways, and in activated T-cells it influences the Ras/MAPK pathway directly or indirectly. It also regulates TP53-mediated transcription and helps determine cell fate in the genotoxic stress response: together with KLF4 it binds the PE21 promoter element of TP53 and represses TP53 activity. Mucin-1 is reported to promote tumour progression. Its subcellular locations include the apical cell membrane, the cell membrane, the cytoplasm and the nucleus, and it is also found in a secreted form.
The protein is expressed on the apical surface of epithelial cells lining mucosal surfaces in tissues such as lung, breast, stomach and pancreas. Overexpression, aberrant intracellular localisation and altered glycosylation have been associated with carcinomas, which is why the CA15-3 designation is used in cancer research. The gene contains a highly polymorphic variable number tandem repeats (VNTR) domain, and alternative splicing gives multiple transcript variants. Aliases include KL-6, EMA, PEM and CD227; earlier names linked the locus to medullary cystic kidney disease 1. The mouse ortholog is Muc1.
Overexpression, mislocalisation and altered glycosylation of mucin-1 are associated with carcinomas, and the protein is reported to promote tumour progression.
As an O-glycosylated mucin on apical epithelial surfaces, it contributes to the protective mucous barrier of tissues such as lung, breast, stomach and pancreas.
The beta subunit modulates ERK, SRC and NF-kappa-B pathways, and influences Ras/MAPK signalling in activated T-cells.
Mucin-1 regulates TP53-mediated transcription and, with KLF4, represses TP53 activity at the PE21 promoter element, influencing cell fate after genotoxic stress.
Mucin-1 is a membrane-bound mucin that helps form protective mucous barriers on epithelial surfaces. Its alpha subunit functions in cell adhesion, and its beta subunit mediates signalling, modulating ERK, SRC and NF-kappa-B pathways and regulating TP53-mediated transcription.
CA15-3 is the name for mucin-1, gene symbol MUC1. Aliases include CD227, PEM, EMA, KL-6, PUM, MCKD and ADMCKD. The protein is cleaved into alpha and beta subunits, and alternative splicing of the gene produces multiple transcript variants.
Overexpression, aberrant intracellular localisation and altered glycosylation of mucin-1 are associated with carcinomas. The mouse ortholog is Muc1. Check the datasheet of any product for its validated reactivity.
Other mucin family members and membrane-bound or secreted mucins with products at Assay Genie.
Gene and protein annotations from HGNC, NCBI Gene and UniProt P15941; product specifications from Assay Genie datasheets.