| Gene Symbol | HLA-DQA2 |
|---|---|
| Entrez Gene | 3118 |
| Alt Symbol | DX-ALPHA, HLA-DXA |
| Species | Human |
| Gene Type | protein-coding |
| Description | major histocompatibility complex, class II, DQ alpha 2 |
| Other Description | DX alpha chain|HLA class II histocompatibility antigen, DQ alpha 2 chain|HLA class II histocompatibility antigen, DQ(6) alpha chain|MHC class II DQA2 |
| Swissprots | O19789 Q5SR04 B0V0E7 Q5SQ94 A2BF37 P01906 |
| Accessions | AAA35772 AAA36249 AAA59605 AAA59761 AAA59834 AAD14077 AFA43495 AKE47356 CAA25142 CAB06493 CEL26596 P01906 M95727 M95728 NM_020056 NP_064440 |
| Function | Binds peptides derived from antigens that access the endocytic route of antigen presenting cells (APC) and presents them on the cell surface for recognition by the CD4 T-cells. The peptide binding cleft accommodates peptides of 10-30 residues. The peptides presented by MHC class II molecules are generated mostly by degradation of proteins that access the endocytic route, where they are processed by lysosomal proteases and other hydrolases. Exogenous antigens that have been endocytosed by the APC are thus readily available for presentation via MHC II molecules, and for this reason this antigen presentation pathway is usually referred to as exogenous. As membrane proteins on their way to degradation in lysosomes as part of their normal turn-over are also contained in the endosomal/lysosomal compartments, exogenous antigens must compete with those derived from endogenous components. Autophagy is also a source of endogenous peptides, autophagosomes constitutively fuse with MHC class II loa |
| Subcellular Location | Cell membrane {ECO:0000269|PubMed:22407913}; Single-pass type I membrane protein {ECO:0000269|PubMed:22407913}. Endoplasmic reticulum membrane {ECO:0000269|PubMed:22407913}; Single-pass type I membrane protein {ECO:0000269|PubMed:22407913}. Golgi apparatus, trans-Golgi network membrane {ECO:0000269|PubMed:22407913}; Single-pass type I membrane protein {ECO:0000269|PubMed:22407913}. Endosome membrane {ECO:0000269|PubMed:22407913}; Single-pass type I membrane protein {ECO:0000269|PubMed:22407913}. Lysosome membrane {ECO:0000269|PubMed:22407913}; Single-pass type I membrane protein {ECO:0000269|PubMed:22407913}. Note=The MHC class II complex transits through a number of intracellular compartments in the endocytic pathway until it reaches the cell membrane for antigen presentation. |
| Tissue Specificity | Restricted to skin Langerhans cells, although some expression at low levels may occur at the surface of B lymphoblastoid cells. {ECO:0000269|PubMed:22407913, ECO:0000269|PubMed:9036956}. |
| Top Pathways | Inflammatory bowel disease (IBD), HTLV-I infection, Influenza A, Tuberculosis, Herpes simplex infection |