CD63
Identifiers
Aliases	CD63, LAMP-3, ME491, MLA1, OMA81H, TSPAN30, CD63 molecule
External IDs	OMIM: 155740 MGI: 99529 HomoloGene: 37526 GeneCards: CD63
Gene location (Human) Chr. Chromosome 12 (human)[1] Band 12q13.2 Start 55,725,323 bp[1] End 55,729,707 bp[1]
Gene location (Mouse) Chr. Chromosome 10 (mouse)[2] Band 10 D3|10 77.19 cM Start 128,736,858 bp[2] End 128,748,691 bp[2]
RNA expression pattern Bgee Human Mouse (ortholog) Top expressed in stromal cell of endometrium lower lobe of lung upper lobe of lung left adrenal gland olfactory bulb upper lobe of left lung ascending aorta smooth muscle tissue corpus epididymis right adrenal gland Top expressed in proximal tubule kidney islet of Langerhans morula blastocyst yolk sac stomach urinary bladder adrenal gland lung More reference expression data BioGPS More reference expression data
Gene ontology Molecular function protein binding Cellular component integral component of membrane multivesicular body endosome multivesicular body membrane membrane late endosome membrane intrinsic component of plasma membrane melanosome plasma membrane integral component of plasma membrane endosome lumen multivesicular body, internal vesicle lysosomal membrane extracellular region platelet dense granule membrane lysosome endosome membrane extracellular exosome extracellular space cell surface azurophil granule membrane late endosome Biological process positive regulation of receptor internalization platelet degranulation pigment granule maturation endosome to melanosome transport protein transport positive regulation of integrin-mediated signaling pathway cell-matrix adhesion cell migration neutrophil degranulation transport pigmentation pigment cell differentiation regulation of vascular endothelial growth factor signaling pathway cell surface receptor signaling pathway positive regulation of endocytosis regulation of potassium ion transmembrane transport Sources:Amigo / QuickGO
Orthologs Species Human Mouse Entrez 967 12512 Ensembl ENSG00000135404 ENSMUSG00000025351 UniProt P08962 P41731 RefSeq (mRNA) NM_001780 NM_001040034 NM_001257389 NM_001257390 NM_001257391 NM_001257392 NM_001257400 NM_001257401 NM_001267698 NM_001042580 NM_001282966 NM_007653 RefSeq (protein) NP_001244318 NP_001244319 NP_001244320 NP_001244321 NP_001244329 NP_001244330 NP_001254627 NP_001771 NP_001036045 NP_001269895 NP_031679 Location (UCSC) Chr 12: 55.73 – 55.73 Mb Chr 10: 128.74 – 128.75 Mb PubMed search [3] [4]
Wikidata
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CD63 antigen is a protein that, in humans, is encoded by the CD63 gene.^[5] CD63 is mainly associated with membranes of intracellular vesicles, although cell surface expression may be induced.

Function

The protein encoded by this gene is a member of the transmembrane 4 superfamily, also known as the tetraspanin family. Most of these members are cell-surface proteins that are characterized by the presence of four hydrophobic domains. The proteins mediate signal transduction events that play a role in the regulation of cell development, activation, growth, and motility. This encoded protein is a cell surface glycoprotein that is known to complex with integrins. It may function as a blood platelet activation marker. Deficiency of this protein is associated with Hermansky-Pudlak Syndrome . Also this gene has been associated with tumor progression. The use of alternate polyadenylation sites has been found for this gene. Alternative splicing results in multiple transcript variants encoding different proteins.^[5]

Allergy diagnosis

CD63 is a good marker for flow cytometric quantification of in vitro activated basophils for diagnosis of IgE-mediated allergy. The test is commonly designated as basophil activation test (BAT).

Research

Initially, deletion and point mutants were used to investigate the role of the C-terminus, which contains a putative lysosomal-targeting/internalisation motif (GYEVM). C-terminal mutants showed increased surface expression and decreased intracellular localisation relative to CD63Wt. Antibody induced internalisation was reduced in C-terminal deletion mutants and abolished in G→A and Y→A mutants, showing the crucial role of these residues in internalisation.

CD63 is extensively and variably glycosylated and the EC2 region contain three potential N-linked glycosylation sites (N130, N150, and N172). Mutants N130A and N150A were similar to hCD63Wt with respect to intracellular localisation and internalisation. However, the hCD63N172A mutant showed a mainly cell surface localisation and low internalisation. Expression of a mutant lacking all three glycosylation sites was very unstable. It was speculated that the reduced internalisation of CD63N172A might be due to changes in its interaction with cell surface molecules. Immunoprecipitation experiments showed some evidence of a protein (100kDa) associating with CD63N172A, but this was not consistent. However, an association between CD63Wt and β2 integrin (CD18) was shown by co-internalisation of these proteins. Interactions with CD63 may therefore affect the trafficking and function of β2 integrins.

In cell biology, CD63 is often used as a marker for multivesicular bodies, which in some cells are enriched with CD63,^[6] as well as for extracellular vesicles released from either the multivesicular body or the plasma membrane.^[7]

Interactions

CD63 has been shown to interact with CD117^[8] and CD82.^[9]

See also

• Cluster of differentiation

References

Further reading

External links

• CD63+protein,+human at the U.S. National Library of Medicine Medical Subject Headings (MeSH)
• Human CD63 genome location and CD63 gene details page in the UCSC Genome Browser.

This article incorporates text from the United States National Library of Medicine, which is in the public domain.