ID:CD81_HUMAN 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.
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.
ModBase Predicted Comparative 3D Structure on P60033
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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.
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
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Sequence and Links to Tools and Databases 
Common Gene Haplotype Alleles 
