|CD84||GR6, p75, SLAMF5, Hly9-β|
|Molecule Type||Antigen Expression||Molecular Weight|
Min / Max
|Non-lineage Restricted Molecule|
Type 1 glycoprotein
|64 / 64|
82 / 82
|CD84 is expressed on virtually all thymocytes. CD4- and CD8- immature thymocytes express the highest levels of CD84. Expression in human and mouse is restricted to hematopoietic tissues and cells. It is expressed at high levels on B cells, NK cells, CD45R0+ T cells and monocytes and at low levels on other cells such as granulocytes, platelets, polymorphs and T cells. It is highly expressed on tissue macrophages but is not expressed on plasma cells.|
|MOLECULAR FAMILY NAME: Belongs to the immunoglobulin supergene family.|
CD84 is a single-pass type 1 glycoprotein. It contains a 21 signal sequence, an 189 aa extracellular domain which contains an Ig-like V-type NH-2 terminal domain that lacks the disulphide bond between the β sheets, an Ig-like C2-type domain with 2 putatuve disulphide bonds and has 4 N-linked and 29 O linked glycosylation sites, a 25 aa hydrophic transmembrane region and a 83 aa cytoplasmic domain containing 5 tyrosines and Src homology 2 (SH2) domain binding motifs (TxYxxV/I) common to the cytoplasmic domains of CD2 family members. The extracellular Ig-like domains show structural and sequence homology with a group of members of the Ig superfamily that include CD2, CD48, CD58, CD150 (SLAM), 2B4 and Ly-9. The members of this family have shown to act as adhesion and co-stimulatory molecules.
MOLECULAR MASS OF CD84
Alternative splicing yields 7 different isoforms.
CD84 is highly N-glycosylated and has 4 potential N-linked glycosylation sites and 29 O-linked glycosylatiuon sites in the extracellular domain.
| LIGANDS AND MOLECULES ASSOCIATED WITH CD84: No information.|
|The CD84 function is unknown but the structural similarties to other adhesion molecules such as CD2 and CD48 suggest a function of intracellular interaction and signaling. CD84 functions as a homotypic adhesion molecule and as a lymphocytic costimulatory molecule. Ligation of CD84 by mAb enchances proliferation of anti-CD3 mAb stimulated human T cells and enhances IFN-γ secretion by lymphocytes. CD84 associates with cytoplasmic, SH2 domain-containing peptides SAP and EAT-2. The cytoplasmic tail contains 2 tyrosine based motifs also found in the cytoplasmic domain of CD150 (SLAM), CD244 (2B4) and CD229 (Ly-9). This motif is critical for binding CD150 and CD244 to a protein SLAM-associated protein (SAP) or SH2D1a that is mutated in the immunodeficiency X-linked lymphoproliferative syndrome. It has been proposed that impaired signaling via this receptor is responsible for immunodeficiency. |
BIOCHEMICAL ACTIVITY: No information.
DISEASE RELEVANCE AND FUNCTION OF CD84 IN INTACT ANIMAL: No information.
|MOLECULAR INTERACTIONS -|
PROTEINS AND DNA ELEMENTS WHICH REGULATE TRANSCRIPTION OF CD84: No information.
SUBSTRATES: No information.
ENZYMES WHICH MODIFY CD84: No information.
Treatment of CD84 causes phosphorylation of tryosine residues. Indications suggest that the tyrosine phosphatase SHP-2 binds to cytoplasmic tail.
Database accession numbers
Revised June 25, 2008