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6a2b
From Proteopedia
(Difference between revisions)
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<StructureSection load='6a2b' size='340' side='right'caption='[[6a2b]], [[Resolution|resolution]] 2.80Å' scene=''> | <StructureSection load='6a2b' size='340' side='right'caption='[[6a2b]], [[Resolution|resolution]] 2.80Å' scene=''> | ||
== Structural highlights == | == Structural highlights == | ||
| - | <table><tr><td colspan='2'>[[6a2b]] is a 3 chain structure. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=6A2B OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=6A2B FirstGlance]. <br> | + | <table><tr><td colspan='2'>[[6a2b]] is a 3 chain structure with sequence from [http://en.wikipedia.org/wiki/African_clawed_frog African clawed frog]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=6A2B OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=6A2B FirstGlance]. <br> |
| - | </td></tr><tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=6a2b FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=6a2b OCA], [http://pdbe.org/6a2b PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=6a2b RCSB], [http://www.ebi.ac.uk/pdbsum/6a2b PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=6a2b ProSAT]</span></td></tr> | + | </td></tr><tr id='gene'><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">b2m ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=8355 African clawed frog])</td></tr> |
| + | <tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=6a2b FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=6a2b OCA], [http://pdbe.org/6a2b PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=6a2b RCSB], [http://www.ebi.ac.uk/pdbsum/6a2b PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=6a2b ProSAT]</span></td></tr> | ||
</table> | </table> | ||
== Function == | == Function == | ||
[[http://www.uniprot.org/uniprot/B2MG_XENLA B2MG_XENLA]] Component of the class I major histocompatibility complex (MHC). Involved in the presentation of peptide antigens to the immune system (By similarity). | [[http://www.uniprot.org/uniprot/B2MG_XENLA B2MG_XENLA]] Component of the class I major histocompatibility complex (MHC). Involved in the presentation of peptide antigens to the immune system (By similarity). | ||
| + | <div style="background-color:#fffaf0;"> | ||
| + | == Publication Abstract from PubMed == | ||
| + | The African clawed frog, Xenopus laevis, is a model species for amphibians. Before metamorphosis, tadpoles do not efficiently express the single classical MHC class I (MHC-I) molecule Xela-UAA, but after metamorphosis, adults express this molecule in abundance. To elucidate the Ag-presenting mechanism of Xela-UAA, in this study, the Xela-UAA structure complex (pXela-UAAg) bound with a peptide from a synthetic random peptide library was determined. The amino acid homology between the Xela-UAA and MHC-I sequences of different species is <45%, and these differences are fully reflected in the three-dimensional structure of pXela-UAAg. Because of polymorphisms and interspecific differences in amino acid sequences, pXela-UAAg forms a distinct peptide-binding groove and presents a unique peptide profile. The most important feature of pXela-UAAg is the two-amino acid insertion in the alpha2-helical region, which forms a protrusion of approximately 3.8 A that is involved in TCR docking. Comparison of peptide-MHC-I complex (pMHC-I) structures showed that only four amino acids in beta2-microglobulin that were bound to MHC-I are conserved in almost all jawed vertebrates, and the most unique feature in nonmammalian pMHC-I molecules is that the AB loop bound beta2-microglobulin. Additionally, the binding distance between pMHC-I and CD8 molecules in nonmammals is different from that in mammals. These unique features of pXela-UAAg provide enhanced knowledge of T cell immunity and bridge the knowledge gap regarding the coevolutionary progression of the MHC-I complex from aquatic to terrestrial species. | ||
| + | |||
| + | A Glimpse of the Peptide Profile Presentation by Xenopus laevis MHC Class I: Crystal Structure of pXela-UAA Reveals a Distinct Peptide-Binding Groove.,Ma L, Zhang N, Qu Z, Liang R, Zhang L, Zhang B, Meng G, Dijkstra JM, Li S, Xia MC J Immunol. 2019 Nov 27. pii: jimmunol.1900865. doi: 10.4049/jimmunol.1900865. PMID:31776204<ref>PMID:31776204</ref> | ||
| + | |||
| + | From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | ||
| + | </div> | ||
| + | <div class="pdbe-citations 6a2b" style="background-color:#fffaf0;"></div> | ||
| + | == References == | ||
| + | <references/> | ||
__TOC__ | __TOC__ | ||
</StructureSection> | </StructureSection> | ||
| + | [[Category: African clawed frog]] | ||
[[Category: Large Structures]] | [[Category: Large Structures]] | ||
[[Category: Ma, L Z]] | [[Category: Ma, L Z]] | ||
Revision as of 17:37, 11 December 2019
Crystal Structure of Xenopus laevis MHC I complex
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