Human Gene CD81 (ENST00000263645.9) Description and Page Index
  Description: Homo sapiens CD81 molecule (CD81), transcript variant 1, mRNA. (from RefSeq NM_004356)
RefSeq Summary (NM_004356): 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. This protein appears to promote muscle cell fusion and support myotube maintenance. Also it may be involved in signal transduction. This gene is localized in the tumor-suppressor gene region and thus it is a candidate gene for malignancies. Two transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Jul 2014].
Gencode Transcript: ENST00000263645.9
Gencode Gene: ENSG00000110651.11
Transcript (Including UTRs)
   Position: hg38 chr11:2,377,294-2,397,419 Size: 20,126 Total Exon Count: 8 Strand: +
Coding Region
   Position: hg38 chr11:2,377,550-2,396,866 Size: 19,317 Coding Exon Count: 8 

Page IndexSequence and LinksUniProtKB CommentsMalaCardsCTDRNA-Seq Expression
Microarray ExpressionRNA StructureProtein StructureOther SpeciesGO AnnotationsmRNA Descriptions
PathwaysOther NamesMethods
Data last updated: 2019-09-04

-  Sequence and Links to Tools and Databases
Genomic Sequence (chr11:2,377,294-2,397,419)mRNA (may differ from genome)Protein (236 aa)
Gene SorterGenome BrowserOther Species FASTAGene interactionsTable SchemaBioGPS
CGAPEnsemblEntrez GeneExonPrimerGeneCardsHGNC
ReactomeStanford SOURCEUniProtKBWikipedia

-  Comments and Description Text from UniProtKB
DESCRIPTION: RecName: Full=CD81 antigen; AltName: Full=26 kDa cell surface protein TAPA-1; AltName: Full=Target of the antiproliferative antibody 1; AltName: Full=Tetraspanin-28; Short=Tspan-28; AltName: CD_antigen=CD81;
FUNCTION: May play an important role in the regulation of lymphoma cell growth. Interacts with a 16-kDa Leu-13 protein to form a complex possibly involved in signal transduction. May act as the viral receptor for HCV.
SUBUNIT: Plays a critical role in HCV attachment and/or cell entry by interacting with HCV E1/E2 glycoproteins heterodimer. Interacts directly with IGSF8. Interacts with CD53 and SCIMP. Interacts with IFITM2 and IFITM3 (By similarity). Interacts with IFITM1.
SUBCELLULAR LOCATION: Membrane; Multi-pass membrane protein.
TISSUE SPECIFICITY: Hematolymphoid, neuroectodermal and mesenchymal tumor cell lines.
PTM: Not glycosylated (Probable).
DISEASE: Defects in CD81 are the cause of immunodeficiency common variable type 6 (CVID6) [MIM:613496]; also called antibody deficiency due to CD81 defect. CVID6 is a primary immunodeficiency characterized by antibody deficiency, hypogammaglobulinemia, recurrent bacterial infections and an inability to mount an antibody response to antigen. The defect results from a failure of B-cell differentiation and impaired secretion of immunoglobulins; the numbers of circulating B-cells is usually in the normal range, but can be low.
SIMILARITY: Belongs to the tetraspanin (TM4SF) family.

-  MalaCards Disease Associations
  MalaCards Gene Search: CD81
Diseases sorted by gene-association score: immunodeficiency, common variable, 6* (919), cd81-related common variable immune deficiency* (400), common variable immunodeficiency* (118), hepatitis c (45), hepatitis (13), cryoglobulinemia (10), hepatitis c virus (8), pediatric lymphoma (7), atrial septal defect 1 (7), malaria (4), viral infectious disease (2), hepatocellular carcinoma (2)
* = Manually curated disease association

-  Comparative Toxicogenomics Database (CTD)
  The following chemicals interact with this gene           more ... click here to view the complete list

-  RNA-Seq Expression Data from GTEx (53 Tissues, 570 Donors)
  Highest median expression: 384.40 RPKM in Uterus
Total median expression: 8481.78 RPKM

View in GTEx track of Genome Browser    View at GTEx portal     View GTEx Body Map

+  Microarray Expression Data
  Press "+" in the title bar above to open this section.

-  mRNA Secondary Structure of 3' and 5' UTRs
RegionFold EnergyBasesEnergy/Base
Display As
5' UTR -118.10256-0.461 Picture PostScript Text
3' UTR -209.20553-0.378 Picture PostScript Text

The RNAfold program from the Vienna RNA Package is used to perform the secondary structure predictions and folding calculations. The estimated folding energy is in kcal/mol. The more negative the energy, the more secondary structure the RNA is likely to have.

-  Protein Domain and Structure Information
  InterPro Domains: Graphical view of domain structure
IPR023396 - CD81_extracellular
IPR000301 - Tetraspanin
IPR018499 - Tetraspanin/Peripherin
IPR018503 - Tetraspanin_CS
IPR008952 - Tetraspanin_EC2

Pfam Domains:
PF00335 - Tetraspanin family

Protein Data Bank (PDB) 3-D Structure
MuPIT help

- X-ray MuPIT

- X-ray MuPIT

- Model

ModBase Predicted Comparative 3D Structure on P60033
The pictures above may be empty if there is no ModBase structure for the protein. The ModBase structure frequently covers just a fragment of the protein. You may be asked to log onto ModBase the first time you click on the pictures. It is simplest after logging in to just click on the picture again to get to the specific info on that model.

-  Orthologous Genes in Other Species
  Orthologies between human, mouse, and rat are computed by taking the best BLASTP hit, and filtering out non-syntenic hits. For more distant species reciprocal-best BLASTP hits are used. Note that the absence of an ortholog in the table below may reflect incomplete annotations in the other species rather than a true absence of the orthologous gene.
MouseRatZebrafishD. melanogasterC. elegansS. cerevisiae
Genome BrowserGenome BrowserNo orthologGenome BrowserNo orthologNo ortholog
Gene Details     
Gene Sorter     
Protein SequenceProtein Sequence Protein Sequence  
AlignmentAlignment Alignment  

-  Gene Ontology (GO) Annotations with Structured Vocabulary
  Molecular Function:
GO:0001618 virus receptor activity
GO:0005178 integrin binding
GO:0005515 protein binding
GO:0023026 MHC class II protein complex binding
GO:1990459 transferrin receptor binding

Biological Process:
GO:0000187 activation of MAPK activity
GO:0007166 cell surface receptor signaling pathway
GO:0008104 protein localization
GO:0008283 cell proliferation
GO:0008284 positive regulation of cell proliferation
GO:0016032 viral process
GO:0030449 regulation of complement activation
GO:0030890 positive regulation of B cell proliferation
GO:0031623 receptor internalization
GO:0031647 regulation of protein stability
GO:0043128 positive regulation of 1-phosphatidylinositol 4-kinase activity
GO:0045944 positive regulation of transcription from RNA polymerase II promoter
GO:0046718 viral entry into host cell
GO:0046813 receptor-mediated virion attachment to host cell
GO:0050731 positive regulation of peptidyl-tyrosine phosphorylation
GO:0050776 regulation of immune response
GO:0061462 protein localization to lysosome
GO:0071404 cellular response to low-density lipoprotein particle stimulus
GO:1904352 positive regulation of protein catabolic process in the vacuole
GO:2000145 regulation of cell motility

Cellular Component:
GO:0001772 immunological synapse
GO:0005886 plasma membrane
GO:0005887 integral component of plasma membrane
GO:0005925 focal adhesion
GO:0016020 membrane
GO:0016021 integral component of membrane
GO:0016323 basolateral plasma membrane
GO:0031982 vesicle
GO:0070062 extracellular exosome

-  Descriptions from all associated GenBank mRNAs
  LF205116 - JP 2014500723-A/12619: Polycomb-Associated Non-Coding RNAs.
MA440693 - JP 2018138019-A/12619: Polycomb-Associated Non-Coding RNAs.
LF207989 - JP 2014500723-A/15492: Polycomb-Associated Non-Coding RNAs.
MA443566 - JP 2018138019-A/15492: Polycomb-Associated Non-Coding RNAs.
LF213931 - JP 2014500723-A/21434: Polycomb-Associated Non-Coding RNAs.
MA449508 - JP 2018138019-A/21434: Polycomb-Associated Non-Coding RNAs.
BC093047 - Homo sapiens CD81 molecule, mRNA (cDNA clone MGC:111086 IMAGE:30398483), complete cds.
M33680 - Human 26-kDa cell surface protein TAPA-1 mRNA, complete cds.
LF370743 - JP 2014500723-A/178246: Polycomb-Associated Non-Coding RNAs.
MA606320 - JP 2018138019-A/178246: Polycomb-Associated Non-Coding RNAs.
BC002978 - Homo sapiens CD81 molecule, mRNA (cDNA clone MGC:2221 IMAGE:3510634), complete cds.
DQ891836 - Synthetic construct clone IMAGE:100004466; FLH180429.01X; RZPDo839C02134D CD81 molecule (CD81) gene, encodes complete protein.
DQ891849 - Synthetic construct Homo sapiens clone IMAGE:100004479; FLH263553.01X; RZPDo839D11134D CD81 molecule (CD81) gene, encodes complete protein.
DQ895022 - Synthetic construct Homo sapiens clone IMAGE:100009482; FLH180425.01L; RZPDo839C02133D CD81 molecule (CD81) gene, encodes complete protein.
KJ890874 - Synthetic construct Homo sapiens clone ccsbBroadEn_00268 CD81 gene, encodes complete protein.
BT019507 - Homo sapiens CD81 antigen (target of antiproliferative antibody 1) mRNA, complete cds.
BT019508 - Homo sapiens CD81 antigen (target of antiproliferative antibody 1) mRNA, complete cds.
LF205118 - JP 2014500723-A/12621: Polycomb-Associated Non-Coding RNAs.
MA440695 - JP 2018138019-A/12621: Polycomb-Associated Non-Coding RNAs.
LF205120 - JP 2014500723-A/12623: Polycomb-Associated Non-Coding RNAs.
MA440697 - JP 2018138019-A/12623: Polycomb-Associated Non-Coding RNAs.
LF370754 - JP 2014500723-A/178257: Polycomb-Associated Non-Coding RNAs.
MA606331 - JP 2018138019-A/178257: Polycomb-Associated Non-Coding RNAs.
AB209380 - Homo sapiens mRNA for CD81 antigen variant protein.
LF370759 - JP 2014500723-A/178262: Polycomb-Associated Non-Coding RNAs.
MA606336 - JP 2018138019-A/178262: Polycomb-Associated Non-Coding RNAs.
LF370760 - JP 2014500723-A/178263: Polycomb-Associated Non-Coding RNAs.
MA606337 - JP 2018138019-A/178263: Polycomb-Associated Non-Coding RNAs.
LF370763 - JP 2014500723-A/178266: Polycomb-Associated Non-Coding RNAs.
MA606340 - JP 2018138019-A/178266: Polycomb-Associated Non-Coding RNAs.
KM576715 - Homo sapiens clone CD81-TSSC4_C8middle-T1 mRNA sequence.
LF370765 - JP 2014500723-A/178268: Polycomb-Associated Non-Coding RNAs.
MA606342 - JP 2018138019-A/178268: Polycomb-Associated Non-Coding RNAs.
LF370766 - JP 2014500723-A/178269: Polycomb-Associated Non-Coding RNAs.
MA606343 - JP 2018138019-A/178269: Polycomb-Associated Non-Coding RNAs.
LF370767 - JP 2014500723-A/178270: Polycomb-Associated Non-Coding RNAs.
MA606344 - JP 2018138019-A/178270: Polycomb-Associated Non-Coding RNAs.
LF370768 - JP 2014500723-A/178271: Polycomb-Associated Non-Coding RNAs.
MA606345 - JP 2018138019-A/178271: Polycomb-Associated Non-Coding RNAs.
JD384432 - Sequence 365456 from Patent EP1572962.
LF370769 - JP 2014500723-A/178272: Polycomb-Associated Non-Coding RNAs.
MA606346 - JP 2018138019-A/178272: Polycomb-Associated Non-Coding RNAs.
JD246589 - Sequence 227613 from Patent EP1572962.
JD474115 - Sequence 455139 from Patent EP1572962.
JD261087 - Sequence 242111 from Patent EP1572962.
LF370770 - JP 2014500723-A/178273: Polycomb-Associated Non-Coding RNAs.
MA606347 - JP 2018138019-A/178273: Polycomb-Associated Non-Coding RNAs.
JD111717 - Sequence 92741 from Patent EP1572962.

-  Biochemical and Signaling Pathways
  KEGG - Kyoto Encyclopedia of Genes and Genomes
hsa04662 - B cell receptor signaling pathway

Reactome (by CSHL, EBI, and GO)

Protein P60033 (Reactome details) participates in the following event(s):

R-HSA-199518 C3d-complexed antigen binds to complement receptor
R-HSA-8853252 CR2:C3d,C3dg,iC3b binds CD19:CD81
R-HSA-198933 Immunoregulatory interactions between a Lymphoid and a non-Lymphoid cell
R-HSA-977606 Regulation of Complement cascade
R-HSA-1280218 Adaptive Immune System
R-HSA-166658 Complement cascade
R-HSA-168256 Immune System
R-HSA-168249 Innate Immune System

-  Other Names for This Gene
  Alternate Gene Symbols: CD81_HUMAN, NM_004356, P18582, P60033, Q5U0J6, TAPA1, TSPAN28, uc001lwf.1, uc001lwf.2
UCSC ID: uc001lwf.2
RefSeq Accession: NM_004356
Protein: P60033 (aka CD81_HUMAN)
CCDS: CCDS7734.1

-  Methods, Credits, and Use Restrictions
  Click here for details on how this gene model was made and data restrictions if any.