CD81
entrez
975
canonical
uniprot
P60033
canonical
ensembl
ENSG00000110651
resolver
ensp
ENSP00000263645
resolver
ensp
ENSP00000370424
resolver
ensp
ENSP00000431780
resolver
ensp
ENSP00000433178
resolver
ensp
ENSP00000433767
resolver
ensp
ENSP00000435633
resolver
ensp
ENSP00000437242
resolver
ensp
ENSP00000575103
resolver
ensp
ENSP00000575108
resolver
enst
ENST00000263645
resolver
enst
ENST00000381036
resolver
enst
ENST00000475945
resolver
enst
ENST00000492627
resolver
enst
ENST00000526072
resolver
enst
ENST00000533417
resolver
enst
ENST00000905044
resolver
genesymbol
CD81
resolver
genesymbol_syn
TAPA1
resolver
genesymbol_syn
TSPAN28
resolver
hgnc
HGNC:1701
resolver
uniprot
A6NMH8
resolver
uniprot
E9PJK1
resolver
uniprot
E9PM31
resolver
uniprot
H0YEE2
resolver
uniprot
P18582
resolver
uniprot
Q5U0J6
resolver
uniprot_entry
A6NMH8_HUMAN
resolver
uniprot_entry
CD81_HUMAN
resolver
uniprot_entry
E9PJK1_HUMAN
resolver
uniprot_entry
H0YEE2_HUMAN
resolver
uniprot_sec
E9PM31
resolver
uniprot_sec
P18582
resolver
uniprot_sec
Q5U0J6
resolver
amino_acid_sequence
MGVEGCTKCIKYLLFVFNFVFWLAGGVILGVALWLRHDPQTTNLLYLELGDKPAPNTFYVGIYILIAVGAVMMFVGFLGCYGAIQESQCLLGTFFTCLVILFACEVAAGIWGFVNKDQIAKDVKQFYDQALQQAVVDDDANNAKAVVKTFHETLDCCGSSTLTALTTSVLKNNLCPSGSNIISNLFKEDCHQKIDDLFSGKLYLIGIAAIVVAVIMIFEMILSMVLCCGIRNSSVY
uniprot
proteins
disease_involvement
DISEASE: Immunodeficiency, common variable, 6 (CVID6) [MIM:613496]: 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. {ECO:0000269|PubMed:20237408}. Note=The disease is caused by variants affecting the gene represented in this entry.
uniprot
proteins
function
FUNCTION: Structural component of specialized membrane microdomains known as tetraspanin-enriched microdomains (TERMs), which act as platforms for receptor clustering and signaling. Essential for trafficking and compartmentalization of CD19 receptor on the surface of activated B cells (PubMed:16449649, PubMed:20237408, PubMed:27881302). Upon initial encounter with microbial pathogens, enables the assembly of CD19-CR2/CD21 and B cell receptor (BCR) complexes at signaling TERMs, lowering the threshold dose of antigen required to trigger B cell clonal expansion and antibody production (PubMed:15161911, PubMed:20237408). In T cells, facilitates the localization of CD247/CD3 zeta at antigen-induced synapses with B cells, providing for costimulation and polarization toward T helper type 2 phenotype (PubMed:22307619, PubMed:23858057, PubMed:8766544). Present in MHC class II compartments, may also play a role in antigen presentation (PubMed:8409388, PubMed:8766544). Can act both as positive and negative regulator of homotypic or heterotypic cell-cell fusion processes. Positively regulates sperm-egg fusion and may be involved in acrosome reaction (By similarity). In myoblasts, associates with CD9 and PTGFRN and inhibits myotube fusion during muscle regeneration (By similarity). In macrophages, associates with CD9 and beta-1 and beta-2 integrins, and prevents macrophage fusion into multinucleated giant cells specialized in ingesting complement-opsonized large particles (PubMed:12796480). Also prevents the fusion of mononuclear cell progenitors into osteoclasts in charge of bone resorption (By similarity). May regulate the compartmentalization of enzymatic activities. In T cells, defines the subcellular localization of dNTPase SAMHD1 and permits its degradation by the proteasome, thereby controlling intracellular dNTP levels (PubMed:28871089). Also involved in cell adhesion and motility. Positively regulates integrin-mediated adhesion of macrophages, particularly relevant for the inflammatory response in the lung (By similarity). {ECO:0000250|UniProtKB:P35762, ECO:0000269|PubMed:12796480, ECO:0000269|PubMed:15161911, ECO:0000269|PubMed:16449649, ECO:0000269|PubMed:20237408, ECO:0000269|PubMed:22307619, ECO:0000269|PubMed:23858057, ECO:0000269|PubMed:27881302, ECO:0000269|PubMed:28871089, ECO:0000269|PubMed:8409388, ECO:0000269|PubMed:8766544}.; FUNCTION: (Microbial infection) Acts as a receptor for hepatitis C virus (HCV) in hepatocytes. Association with CLDN1 and the CLDN1-CD81 receptor complex is essential for HCV entry into host cell. {ECO:0000269|PubMed:20375010, ECO:0000269|PubMed:21516087, ECO:0000269|PubMed:26116703, ECO:0000269|PubMed:26354436}.; FUNCTION: (Microbial infection) Involved in SAMHD1-dependent restriction of HIV-1 replication. May support early replication of both R5- and X4-tropic HIV-1 viruses in T cells, likely via proteasome-dependent degradation of SAMHD1. {ECO:0000269|PubMed:28871089}.; FUNCTION: (Microbial infection) Specifically required for Plasmodium falciparum infectivity of hepatocytes, controlling sporozoite entry into hepatocytes via the parasitophorous vacuole and subsequent parasite differentiation to exoerythrocytic forms. {ECO:0000269|PubMed:12483205}.
uniprot
proteins
mass_dalton
25809
uniprot
proteins
mutagenesis
MUTAGEN 116; /note="K->E: Reduces binding to integrin."; /evidence="ECO:0000269|PubMed:27993971"; MUTAGEN 119; /note="I->A: No effect on integrin binding."; /evidence="ECO:0000269|PubMed:27993971"; MUTAGEN 121; /note="K->E: No effect on integrin binding."; /evidence="ECO:0000269|PubMed:27993971"; MUTAGEN 124; /note="K->E: No effect on integrin binding."; /evidence="ECO:0000269|PubMed:27993971"; MUTAGEN 126; /note="F->A: No effect on integrin binding."; /evidence="ECO:0000269|PubMed:27993971"; MUTAGEN 144; /note="K->E: Reduces binding to integrin; when associated with E-148."; /evidence="ECO:0000269|PubMed:27993971"; MUTAGEN 148; /note="K->E: Reduces binding to integrin; when associated with E-144."; /evidence="ECO:0000269|PubMed:27993971"; MUTAGEN 186; /note="F->A: No effect on integrin binding."; /evidence="ECO:0000269|PubMed:27993971"; MUTAGEN 187; /note="K->E: No effect on integrin binding."; /evidence="ECO:0000269|PubMed:27993971"; MUTAGEN 188; /note="E->K,Q: Strongly reduced affinity for HCV protein E2; when associated with E-196."; /evidence="ECO:0000269|PubMed:26116703"; MUTAGEN 188; /note="E->K: Mildly reduced affinity for HCV protein E2."; /evidence="ECO:0000269|PubMed:26116703"; MUTAGEN 196; /note="D->E: Strongly reduced affinity for HCV protein E2; when associated with K-188 or Q-188."; /evidence="ECO:0000269|PubMed:26116703"; MUTAGEN 196; /note="D->K,Q,R: Strongly reduced affinity for HCV protein E2."; /evidence="ECO:0000269|PubMed:26116703"; MUTAGEN 219; /note="E->A,Q: Reduced affinity for cholesterol binding."; /evidence="ECO:0000269|PubMed:27881302
uniprot
proteins
post_translational_modification
PTM: Not glycosylated. {ECO:0000305}.; PTM: Likely constitutively palmitoylated at low levels. Protein palmitoylation is up-regulated upon coligation of BCR and CD9-C2R-CD81 complexes in lipid rafts. {ECO:0000269|PubMed:15161911}.
uniprot
proteins
protein_family
Tetraspanin (TM4SF) family
uniprot
proteins
pubmed
11226150
uniprot
proteins
pubmed
11504738
uniprot
proteins
pubmed
12437138
uniprot
proteins
pubmed
12483205
uniprot
proteins
pubmed
12796480
uniprot
proteins
pubmed
12913001
uniprot
proteins
pubmed
12970454
uniprot
proteins
pubmed
1383329
uniprot
proteins
pubmed
15004227
uniprot
proteins
pubmed
15161911
uniprot
proteins
pubmed
15489334
uniprot
proteins
pubmed
16449649
uniprot
proteins
pubmed
16554811
uniprot
proteins
pubmed
1695320
uniprot
proteins
pubmed
1860863
uniprot
proteins
pubmed
20237408
uniprot
proteins
pubmed
20375010
uniprot
proteins
pubmed
21269460
uniprot
proteins
pubmed
21516087
uniprot
proteins
pubmed
21930792
uniprot
proteins
pubmed
22307619
uniprot
proteins
pubmed
23858057
uniprot
proteins
pubmed
2398277
uniprot
proteins
pubmed
26116703
uniprot
proteins
pubmed
26354436
uniprot
proteins
pubmed
27881302
uniprot
proteins
pubmed
27916518
uniprot
proteins
pubmed
27993971
uniprot
proteins
pubmed
28871089
uniprot
proteins
pubmed
8409388
uniprot
proteins
pubmed
8766544
uniprot
proteins
sequence_length
236
uniprot
proteins
subcellular_location
SUBCELLULAR LOCATION: Cell membrane {ECO:0000269|PubMed:1383329, ECO:0000269|PubMed:1695320, ECO:0000269|PubMed:20237408, ECO:0000269|PubMed:22307619, ECO:0000269|PubMed:2398277, ECO:0000269|PubMed:26354436}; Multi-pass membrane protein {ECO:0000255}. Basolateral cell membrane {ECO:0000269|PubMed:20375010}; Multi-pass membrane protein {ECO:0000255}. Note=Associates with CLDN1 and the CLDN1-CD81 complex localizes to the basolateral cell membrane. {ECO:0000269|PubMed:20375010}.
uniprot
proteins
transmembrane_region
TRANSMEM 13..33; /note="Helical"; /evidence="ECO:0000269|PubMed:27881302"; TRANSMEM 64..84; /note="Helical"; /evidence="ECO:0000269|PubMed:27881302"; TRANSMEM 90..112; /note="Helical"; /evidence="ECO:0000269|PubMed:27881302"; TRANSMEM 202..224; /note="Helical"; /evidence="ECO:0000269|PubMed:27881302
uniprot
proteins