| IED ID | IndEnz0002019163 |
| Enzyme Type ID | protease019163 |
| Protein Name |
CD81 antigen 26 kDa cell surface protein TAPA-1 Target of the antiproliferative antibody 1 CD antigen CD81 |
| Gene Name | Cd81 Tapa1 |
| Organism | Mus musculus (Mouse) |
| Taxonomic Lineage | cellular organisms Eukaryota Opisthokonta Metazoa Eumetazoa Bilateria Deuterostomia Chordata Craniata Vertebrata Gnathostomata (jawed vertebrates) Teleostomi Euteleostomi Sarcopterygii Dipnotetrapodomorpha Tetrapoda Amniota Mammalia Theria Eutheria Boreoeutheria Euarchontoglires Glires (Rodents and rabbits) Rodentia Myomorpha (mice and others) Muroidea Muridae Murinae Mus Mus Mus musculus (Mouse) |
| Enzyme Sequence | MGVEGCTKCIKYLLFVFNFVFWLAGGVILGVALWLRHDPQTTSLLYLELGNKPAPNTFYVGIYILIAVGAVMMFVGFLGCYGAIQESQCLLGTFFTCLVILFACEVAAGIWGFVNKDQIAKDVKQFYDQALQQAVMDDDANNAKAVVKTFHETLNCCGSNALTTLTTTILRNSLCPSGGNILTPLLQQDCHQKIDELFSGKLYLIGIAAIVVAVIMIFEMILSMVLCCGIRNSSVY |
| Enzyme Length | 236 |
| Uniprot Accession Number | P35762 |
| Absorption | |
| Active Site | |
| Activity Regulation | |
| Binding Site | BINDING 219; /note=Cholesterol; /evidence=ECO:0000250|UniProtKB:P60033 |
| Calcium Binding | |
| catalytic Activity | |
| DNA Binding | |
| EC Number | |
| Enzyme 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 cell surface of activated B cells (PubMed:23499492). Upon initial encounter with a microbial pathogen, enables the assembly of CD19-CR2 and B cell receptor complexes at signaling TERMs, lowering the threshold dose of antigen required to trigger B cell clonal expansion and humoral immune response (By similarity). In T cells, associates with CD4 or CD8 coreceptors and defines the maturation state of antigen-induced synapses with B cells (By similarity). Facilitates localization of CD3 in these immune synapses, required for costimulation and sustained activation of T cells, preferentially triggering T helper type 2 immune response (PubMed:11046035). Can act both as positive and negative regulator of homotypic or heterotypic cell-cell fusion processes. In myoblasts, associates with another tetraspanin CD9 in complex with PTGFRN and inhibits myotube fusion during muscle regeneration (PubMed:23575678). 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. Also prevents the fusion between mononuclear cell progenitors into osteoclasts in charge of bone resorption. Positively regulates sperm-egg fusion and may be involved in the acrosome reaction (PubMed:16380109, PubMed:17290409). Regulates protein trafficking in intracellular compartments. In T cells, associates with dNTPase SAMHD1 and defines its subcellular location, enabling its degradation by the proteasome and thereby controlling intracellular dNTP levels (By similarity). Also regulates integrin-dependent migration of macrophages, particularly relevant for inflammatory response in the lung (PubMed:18662991). {ECO:0000250|UniProtKB:P60033, ECO:0000269|PubMed:11046035, ECO:0000269|PubMed:16380109, ECO:0000269|PubMed:17290409, ECO:0000269|PubMed:18662991, ECO:0000269|PubMed:23499492, ECO:0000269|PubMed:23575678}.; FUNCTION: (Microbial infection) Specifically required for Plasmodium yoelii infectivity of hepatocytes, controlling sporozoite entry in hepatocytes via the parasitophorous vacuole and subsequent parasite differentiation to exoerythrocytic forms. {ECO:0000269|PubMed:12483205}. |
| Temperature Dependency | |
| PH Dependency | |
| Pathway | |
| nucleotide Binding | |
| Features | Binding site (1); Chain (1); Disulfide bond (2); Helix (6); Sequence conflict (1); Site (3); Topological domain (5); Transmembrane (4) |
| Keywords | 3D-structure;Adaptive immunity;Cell membrane;Direct protein sequencing;Disulfide bond;Immunity;Lipid-binding;Membrane;Reference proteome;Transmembrane;Transmembrane helix |
| Interact With | |
| Induction | INDUCTION: Up-regulated in response to notexin-induced acute myoinjury. {ECO:0000269|PubMed:23575678}. |
| Subcellular Location | SUBCELLULAR LOCATION: Cell membrane {ECO:0000269|PubMed:23213457}; Multi-pass membrane protein {ECO:0000255}. Basolateral cell membrane {ECO:0000250|UniProtKB:P60033}; Multi-pass membrane protein {ECO:0000255}. Note=Associates with CLDN1 and the CLDN1-CD81 complex localizes to the basolateral cell membrane. {ECO:0000250|UniProtKB:P60033}. |
| Modified Residue | |
| 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:0000250|UniProtKB:P60033}. |
| Signal Peptide | |
| Structure 3D | X-ray crystallography (1) |
| Cross Reference PDB | 3X0F; |
| Mapped Pubmed ID | 10036981; 10512203; 10691133; 10903843; 10907850; 11063728; 11076855; 11167010; 11226150; 11376857; 11504738; 11668390; 11978781; 12086470; 12357429; 12410230; 12473685; 12504561; 12520002; 12904583; 1380797; 14530327; 14532283; 14610273; 14676841; 14681479; 14688345; 14966136; 15226823; 15284116; 15516931; 15516932; 15840001; 15890332; 16054021; 16418227; 16449649; 16615898; 16641285; 16687736; 17021040; 17245608; 17684062; 17967808; 18039842; 18079696; 18163532; 18586096; 18713730; 18799693; 19030166; 19184252; 1971786; 19737782; 20168089; 20459838; 20573698; 20579434; 20882409; 21267068; 21677313; 21931533; 22079629; 22424930; 22564057; 23223239; 23226274; 23395392; 24154525; 24798694; 24803591; 25972472; 26045162; 26329536; 27729526; 27928007; 29572511; 29671763; 32024956; 32150249; 32615086; 32974937; 7590978; 9126932; 9250665; 9380722; 9482907; 9584186; 9618174; 9922400; |
| Motif | |
| Gene Encoded By | |
| Mass | 25,815 |
| Kinetics | |
| Metal Binding | |
| Rhea ID | |
| Cross Reference Brenda |