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| <StructureSection load='2ipk' size='340' side='right'caption='[[2ipk]], [[Resolution|resolution]] 2.30Å' scene=''> | | <StructureSection load='2ipk' size='340' side='right'caption='[[2ipk]], [[Resolution|resolution]] 2.30Å' scene=''> |
| == Structural highlights == | | == Structural highlights == |
- | <table><tr><td colspan='2'>[[2ipk]] is a 4 chain structure with sequence from [https://en.wikipedia.org/wiki/Human Human] and [https://en.wikipedia.org/wiki/Staam Staam]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2IPK OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=2IPK FirstGlance]. <br> | + | <table><tr><td colspan='2'>[[2ipk]] is a 4 chain structure with sequence from [https://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens], [https://en.wikipedia.org/wiki/Influenza_A_virus Influenza A virus] and [https://en.wikipedia.org/wiki/Staphylococcus_aureus_subsp._aureus_Mu50 Staphylococcus aureus subsp. aureus Mu50]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2IPK OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=2IPK FirstGlance]. <br> |
- | </td></tr><tr id='NonStdRes'><td class="sblockLbl"><b>[[Non-Standard_Residue|NonStd Res:]]</b></td><td class="sblockDat"><scene name='pdbligand=4DP:3-[5-(DIMETHYLAMINO)-1,3-DIOXO-1,3-DIHYDRO-2H-ISOINDOL-2-YL]-L-ALANINE'>4DP</scene>, <scene name='pdbligand=ACE:ACETYL+GROUP'>ACE</scene></td></tr> | + | </td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 2.3Å</td></tr> |
- | <tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat"><div style='overflow: auto; max-height: 3em;'>[[1jwu|1jwu]], [[1dlh|1dlh]]</div></td></tr> | + | <tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=4DP:3-[5-(DIMETHYLAMINO)-1,3-DIOXO-1,3-DIHYDRO-2H-ISOINDOL-2-YL]-L-ALANINE'>4DP</scene>, <scene name='pdbligand=ACE:ACETYL+GROUP'>ACE</scene></td></tr> |
- | <tr id='gene'><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">HLA-DRA ([https://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=9606 HUMAN]), HLA-DRB1 ([https://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=9606 HUMAN]), entC3 ([https://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=158878 STAAM])</td></tr>
| + | |
| <tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=2ipk FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2ipk OCA], [https://pdbe.org/2ipk PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=2ipk RCSB], [https://www.ebi.ac.uk/pdbsum/2ipk PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=2ipk ProSAT]</span></td></tr> | | <tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=2ipk FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2ipk OCA], [https://pdbe.org/2ipk PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=2ipk RCSB], [https://www.ebi.ac.uk/pdbsum/2ipk PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=2ipk ProSAT]</span></td></tr> |
| </table> | | </table> |
- | == Disease == | |
- | [[https://www.uniprot.org/uniprot/2B11_HUMAN 2B11_HUMAN]] Genetic variation in HLA-DRB1 is a cause of susceptibility to sarcoidosis type 1 (SS1) [MIM:[https://omim.org/entry/181000 181000]]. Sarcoidosis is an idiopathic, systemic, inflammatory disease characterized by the formation of immune granulomas in involved organs. Granulomas predominantly invade the lungs and the lymphatic system, but also skin, liver, spleen, eyes and other organs may be involved.<ref>PMID:14508706</ref> | |
| == Function == | | == Function == |
- | [[https://www.uniprot.org/uniprot/ENTC3_STAAM ENTC3_STAAM]] Staphylococcal enterotoxins cause the intoxication staphylococcal food poisoning syndrome. The illness is characterized by high fever, hypotension, diarrhea, shock, and in some cases death. [[https://www.uniprot.org/uniprot/DRA_HUMAN DRA_HUMAN]] 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 loading compartments. In addition to APCs, other cells of the gastrointestinal tract, such as epithelial cells, express MHC class II molecules and CD74 and act as APCs, which is an unusual trait of the GI tract. To produce a MHC class II molecule that presents an antigen, three MHC class II molecules (heterodimers of an alpha and a beta chain) associate with a CD74 trimer in the ER to form a heterononamer. Soon after the entry of this complex into the endosomal/lysosomal system where antigen processing occurs, CD74 undergoes a sequential degradation by various proteases, including CTSS and CTSL, leaving a small fragment termed CLIP (class-II-associated invariant chain peptide). The removal of CLIP is facilitated by HLA-DM via direct binding to the alpha-beta-CLIP complex so that CLIP is released. HLA-DM stabilizes MHC class II molecules until primary high affinity antigenic peptides are bound. The MHC II molecule bound to a peptide is then transported to the cell membrane surface. In B-cells, the interaction between HLA-DM and MHC class II molecules is regulated by HLA-DO. Primary dendritic cells (DCs) also to express HLA-DO. Lysosomal miroenvironment has been implicated in the regulation of antigen loading into MHC II molecules, increased acidification produces increased proteolysis and efficient peptide loading. [[https://www.uniprot.org/uniprot/2B11_HUMAN 2B11_HUMAN]] 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 loading compartments. In addition to APCs; other cells of the gastrointestinal tract; such as epithelial cells; express MHC class II molecules and CD74 and act as APCs; which is an unusual trait of the GI tract. To produce a MHC class II molecule that presents an antigen; three MHC class II molecules (heterodimers of an alpha and a beta chain) associate with a CD74 trimer in the ER to form a heterononamer. Soon after the entry of this complex into the endosomal/lysosomal system where antigen processing occurs; CD74 undergoes a sequential degradation by various proteases; including CTSS and CTSL; leaving a small fragment termed CLIP (class-II-associated invariant chain peptide). The removal of CLIP is facilitated by HLA-DM via direct binding to the alpha-beta-CLIP complex so that CLIP is released. HLA-DM stabilizes MHC class II molecules until primary high affinity antigenic peptides are bound. The MHC II molecule bound to a peptide is then transported to the cell membrane surface. In B-cells; the interaction between HLA-DM and MHC class II molecules is regulated by HLA-DO. Primary dendritic cells (DCs) also to express HLA-DO. Lysosomal miroenvironment has been implicated in the regulation of antigen loading into MHC II molecules; increased acidification produces increased proteolysis and efficient peptide loading.
| + | [https://www.uniprot.org/uniprot/DRA_HUMAN DRA_HUMAN] 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 loading compartments. In addition to APCs, other cells of the gastrointestinal tract, such as epithelial cells, express MHC class II molecules and CD74 and act as APCs, which is an unusual trait of the GI tract. To produce a MHC class II molecule that presents an antigen, three MHC class II molecules (heterodimers of an alpha and a beta chain) associate with a CD74 trimer in the ER to form a heterononamer. Soon after the entry of this complex into the endosomal/lysosomal system where antigen processing occurs, CD74 undergoes a sequential degradation by various proteases, including CTSS and CTSL, leaving a small fragment termed CLIP (class-II-associated invariant chain peptide). The removal of CLIP is facilitated by HLA-DM via direct binding to the alpha-beta-CLIP complex so that CLIP is released. HLA-DM stabilizes MHC class II molecules until primary high affinity antigenic peptides are bound. The MHC II molecule bound to a peptide is then transported to the cell membrane surface. In B-cells, the interaction between HLA-DM and MHC class II molecules is regulated by HLA-DO. Primary dendritic cells (DCs) also to express HLA-DO. Lysosomal miroenvironment has been implicated in the regulation of antigen loading into MHC II molecules, increased acidification produces increased proteolysis and efficient peptide loading. |
| == Evolutionary Conservation == | | == Evolutionary Conservation == |
| [[Image:Consurf_key_small.gif|200px|right]] | | [[Image:Consurf_key_small.gif|200px|right]] |
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| ==See Also== | | ==See Also== |
| *[[MHC 3D structures|MHC 3D structures]] | | *[[MHC 3D structures|MHC 3D structures]] |
| + | *[[MHC II 3D structures|MHC II 3D structures]] |
| == References == | | == References == |
| <references/> | | <references/> |
| __TOC__ | | __TOC__ |
| </StructureSection> | | </StructureSection> |
- | [[Category: Human]] | + | [[Category: Homo sapiens]] |
| + | [[Category: Influenza A virus]] |
| [[Category: Large Structures]] | | [[Category: Large Structures]] |
- | [[Category: Staam]] | + | [[Category: Staphylococcus aureus subsp. aureus Mu50]] |
- | [[Category: Nguyen, T T]] | + | [[Category: Nguyen TT]] |
- | [[Category: Stern, L J]] | + | [[Category: Stern LJ]] |
- | [[Category: Dapa]]
| + | |
- | [[Category: Dr1]]
| + | |
- | [[Category: Fluorogenic probe]]
| + | |
- | [[Category: Hla]]
| + | |
- | [[Category: Immune system]]
| + | |
- | [[Category: Major histocompatibility complex]]
| + | |
- | [[Category: Mhc]]
| + | |
- | [[Category: Sec3]]
| + | |
| Structural highlights
Function
DRA_HUMAN 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 loading compartments. In addition to APCs, other cells of the gastrointestinal tract, such as epithelial cells, express MHC class II molecules and CD74 and act as APCs, which is an unusual trait of the GI tract. To produce a MHC class II molecule that presents an antigen, three MHC class II molecules (heterodimers of an alpha and a beta chain) associate with a CD74 trimer in the ER to form a heterononamer. Soon after the entry of this complex into the endosomal/lysosomal system where antigen processing occurs, CD74 undergoes a sequential degradation by various proteases, including CTSS and CTSL, leaving a small fragment termed CLIP (class-II-associated invariant chain peptide). The removal of CLIP is facilitated by HLA-DM via direct binding to the alpha-beta-CLIP complex so that CLIP is released. HLA-DM stabilizes MHC class II molecules until primary high affinity antigenic peptides are bound. The MHC II molecule bound to a peptide is then transported to the cell membrane surface. In B-cells, the interaction between HLA-DM and MHC class II molecules is regulated by HLA-DO. Primary dendritic cells (DCs) also to express HLA-DO. Lysosomal miroenvironment has been implicated in the regulation of antigen loading into MHC II molecules, increased acidification produces increased proteolysis and efficient peptide loading.
Evolutionary Conservation
Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.
Publication Abstract from PubMed
A crucial step in the immune response is the binding of antigenic peptides to major histocompatibility complex (MHC) proteins. Class II MHC proteins present their bound peptides to CD4(+) T cells, thereby helping to activate both the humoral and the cellular arms of the adaptive immune response. Peptide loading onto class II MHC proteins is regulated temporally, spatially and developmentally in antigen-presenting cells. To help visualize these processes, we have developed a series of novel fluorogenic probes that incorporate the environment-sensitive amino acid analogs 6-N,N-dimethylamino-2-3-naphthalimidoalanine and 4-N,N-dimethylaminophthalimidoalanine. Upon binding to class II MHC proteins these fluorophores show large changes in emission spectra, quantum yield and fluorescence lifetime. Peptides incorporating these fluorophores bind specifically to class II MHC proteins on antigen-presenting cells and can be used to follow peptide binding in vivo. Using these probes we have tracked a developmentally regulated cell-surface peptide-binding activity in primary human monocyte-derived dendritic cells.
Fluorogenic probes for monitoring peptide binding to class II MHC proteins in living cells.,Venkatraman P, Nguyen TT, Sainlos M, Bilsel O, Chitta S, Imperiali B, Stern LJ Nat Chem Biol. 2007 Apr;3(4):222-8. Epub 2007 Mar 11. PMID:17351628[1]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
See Also
References
- ↑ Venkatraman P, Nguyen TT, Sainlos M, Bilsel O, Chitta S, Imperiali B, Stern LJ. Fluorogenic probes for monitoring peptide binding to class II MHC proteins in living cells. Nat Chem Biol. 2007 Apr;3(4):222-8. Epub 2007 Mar 11. PMID:17351628 doi:10.1038/nchembio868
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