MUC1 [M10G4]

M10G4

Full length protein (Human). A high molecular weight more than 300 kDa glycoprotein from human milk-fat globule molecule.

Repeat of VNTR extracellular portion of MUC1 molecule. Reacts with VNTR5 and VNTR20?recombinant unglycosylated fragments of MUC1 protein and underglycosylated MUC1. Does not recognize natural MUC1 protein isolated from human milk by affinity purification on carbohydrate. Belongs to Mab cluster 1-4 according to ISOMB TD-4 classification . No cross-reactivity with egg white avidin.

Cell Membrane and Cytoplasmic

From mouse ascitic fluid Storage

ELISA: Use at an assay dependent dilution. Not tested in other applications. Optimal dilutions/concentrations should be determined by the end user. Cellular

The alpha subunit has cell adhesive properties. Can act both as an adhesion and an anti-adhesion protein. May provide a protective layer on epithelial cells against bacterial and enzyme attack.

The alpha subunit forms a tight non-covalent heterodimeric complex with the proteolytically-released beta-subunit. Interaction via the tandem repeat region with domain 1 of ICAM1 is implicated in cell migration and metastases. Isoform 1 binds directly the SH2 domain of GRB2 and forms a MUC1/GRB2/SOS1 complex involved in RAS signaling. The cytoplasmic tail (MUC1CT) interacts with several proteins such as SRC CTNNB1 and ERBs. Interaction with the SH2 domain of CSK decreases interaction with GSK3B. Interacts with CTNNB1/beta-catenin and JUP/gamma-catenin and promotes cell adhesion. Interaction with JUP/gamma-catenin is induced by heregulin. Binds PRKCD ERBB2 ERBB3 and ERBB4. Heregulin (HRG) stimulates the interaction with ERBB2 and to a much lesser extent the interaction with ERBB3 and ERBB4. Interacts with P53 in response to DNA damage. Interacts with KLF4. Interacts with estrogen receptor alpha/ESR1 through its DNA-binding domain and stimulates its transcription activity. Binds ADAM17.

Isoform 5: Secreted.

Isoform 9: Secreted.

Expressed on the apical surface of epithelial cells especially of airway passages breast and uterus. Also expressed in activated and unactivated T-cells. Overexpressed in epithelial tumors such as breast or ovarian cancer and also in non-epithelial tumor cells. Isoform 7 expressed in tumor cells only. Developmental Stage: During fetal development expressed at low levels in the colonic epithelium from 13 weeks of gestation.

Proteolytic cleavage in the SEA domain occurs in the endoplasmic reticulum by an autoproteolytic mechanism and requires the full-length SEA domain as well as requiring a Ser Thr or Cys residue at the P + 1 site. Cleavage at this site also occurs on isoform MUC1/X but not on isoform MUC1/Y. Ectodomain shedding is mediated by ADAM17.

Phosphorylated on tyrosines and serine residues in the C-terminal. Phosphorylation on tyrosines in the C-terminal increases the nuclear location of MUC1 and beta-catenin. Phosphorylation by PKC delta induces binding of MUC1 to beta-catenin/CTNNB1 and thus decreases the formation of the beta-catenin/E-cadherin complex. Src-mediated phosphorylation inhibits interaction with GSK3B. Src- and EGFR-mediated phosphorylation on Tyr-1229 increases binding to beta-catenin/CTNNB1. GSK3beta-mediated phosphorylation on Ser-1227 decreases this interaction but restores the formation of the beta-cadherin/E-cadherin complex. On T-cell receptor activation phosphorylated by LCK. PDGFR-mediated phosphorylation increases nuclear colocalization of MUC1CT and CTNNB1.

Contains 1 SEA domain.