InnateDB: Systems Biology of the Innate Immune Response

Homo sapiens Protein: MUC4

Summary

InnateDB Protein

IDBP-70701.6

Last Modified

2014-10-13 [Report errors or provide feedback]

Gene Symbol

MUC4

Protein Name

mucin 4, cell surface associated

Synonyms

ASGP; HSA276359; MUC-4;

Species

Homo sapiens

Ensembl Protein

ENSP00000304207

InnateDB Gene

IDBG-70699 (MUC4)

Protein Structure

UniProt Annotation

Function

May play a role in tumor progression. Ability to promote tumor growth may be mainly due to repression of apoptosis as opposed to proliferation. Has anti-adhesive properties. Seems to alter cellular behavior through both anti-adhesive effects on cell-cell and cell-extracellular matrix interactions and in its ability to act as an intramembrane ligand for ERBB2. Plays an important role in cell proliferation and differentiation of epithelial cells by inducing specific phosphorylation of ERBB2. The MUC4-ERBB2 complex causes site-specific phosphorylation of the ERBB2 'Tyr-1248'. In polarized epithelilal cells segragates ERBB2 and other ERBB receptors and prevents ERBB2 from acting as a coreceptor. The interaction with ERBB2 leads to enhanced expression of CDKN1B. The formation of a MUC4-ERBB2-ERBB3-NRG1 complex leads to down-regulation of CDKN1B, resulting in repression of apoptosis and stimulation of proliferation. {ECO:0000269PubMed:12102554, ECO:0000269PubMed:16049287, ECO:0000269PubMed:16814944, ECO:0000269PubMed:16914178}.

Subcellular Localization

Membrane {ECO:0000305}; Single-pass membrane protein {ECO:0000305}. Secreted {ECO:0000269PubMed:12102554}. Note=Isoforms lacking the Cys-rich region, EGF-like domains and transmembrane region are secreted. Secretion occurs by splicing or proteolytic processing.Mucin-4 beta chain: Cell membrane; Single- pass membrane protein.Mucin-4 alpha chain: Secreted.Isoform 3: Cell membrane; Single-pass membrane protein.Isoform 11: Secreted.Isoform 15: Secreted.Isoform 17: Cell membrane; Single-pass membrane protein.

Disease Associations

Tissue Specificity

Expressed in the thymus, thyroid, lung, trachea, esophagus, stomach, small intestine, colon, testis, prostate, ovary, uterus, placenta, and mammary and salivary glands. Expressed in carcinomas arising from some of these epithelia, such as lung cancers, squamous cell carcinomas of the upper aerodigestive tract, mammary carcinomas, biliary tract, colon, and cervix cancers. Minimally or not expressed in the normal pancreas or chronic pancreatitis, but is highly expressed in pancreatic tumors and pancreatic tumor cell lines. {ECO:0000269PubMed:10024507, ECO:0000269PubMed:10880978, ECO:0000269PubMed:10920259, ECO:0000269PubMed:16814944}.

Comments

Interactions

Number of Interactions

This gene and/or its encoded proteins are associated with 1 experimentally validated interaction(s) in this database.

Experimentally validated
Total	1 [view]
Protein-Protein	0
Protein-DNA	0
Protein-RNA	0
DNA-DNA	1 [view]
RNA-RNA	0
DNA-RNA	0

Gene Ontology

Molecular Function

Accession	GO Term
GO:0005176	ErbB-2 class receptor binding
GO:0005515	protein binding
GO:0030197	extracellular matrix constituent, lubricant activity

Biological Process

GO:0007160	cell-matrix adhesion
GO:0016266	O-glycan processing
GO:0030277	maintenance of gastrointestinal epithelium
GO:0043687	post-translational protein modification
GO:0044267	cellular protein metabolic process

Cellular Component

GO:0005578	proteinaceous extracellular matrix
GO:0005615	extracellular space
GO:0005796	Golgi lumen
GO:0005887	integral component of plasma membrane
GO:0016020	membrane
GO:0070062	extracellular vesicular exosome