View source for 1ktd


==CRYSTAL STRUCTURE OF CLASS II MHC MOLECULE IEK BOUND TO PIGEON CYTOCHROME C PEPTIDE==
<StructureSection load='1ktd' size='340' side='right'caption='[[1ktd]], [[Resolution|resolution]] 2.40&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[1ktd]] is a 4 chain structure with sequence from [https://en.wikipedia.org/wiki/Columba_livia Columba livia] and [https://en.wikipedia.org/wiki/Mus_musculus Mus musculus]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1KTD OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1KTD FirstGlance]. <br>
</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 2.4&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=NAG:N-ACETYL-D-GLUCOSAMINE'>NAG</scene>, <scene name='pdbligand=SO4:SULFATE+ION'>SO4</scene></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=1ktd FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1ktd OCA], [https://pdbe.org/1ktd PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1ktd RCSB], [https://www.ebi.ac.uk/pdbsum/1ktd PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1ktd ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/HA21_MOUSE HA21_MOUSE] 
== Evolutionary Conservation ==
[[Image:Consurf_key_small.gif|200px|right]]
Check<jmol>
  <jmolCheckbox>
    <scriptWhenChecked>; select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/kt/1ktd_consurf.spt"</scriptWhenChecked>
    <scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview03.spt</scriptWhenUnchecked>
    <text>to colour the structure by Evolutionary Conservation</text>
  </jmolCheckbox>
</jmol>, as determined by [http://consurfdb.tau.ac.il/ ConSurfDB]. You may read the [[Conservation%2C_Evolutionary|explanation]] of the method and the full data available from [http://bental.tau.ac.il/new_ConSurfDB/main_output.php?pdb_ID=1ktd ConSurf].
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== Publication Abstract from PubMed ==
The COOH-terminal peptides of pigeon and moth cytochrome c, bound to mouse IE(k), are two of the most thoroughly studied T cell antigens. We have solved the crystal structures of the moth peptide and a weak agonist-antagonist variant of the pigeon peptide bound to IE(k). The moth peptide and all other peptides whose structures have been solved bound to IE(k), have a lysine filling the p9 pocket of IE(k). However, the pigeon peptide has an alanine at p9 shifting the lysine to p10. Rather than kinking to place the lysine in the anchor pocket, the pigeon peptide takes the extended course through the binding groove, which is characteristic of all other peptides bound to major histocompatibility complex (MHC) class II. Thus, unlike MHC class I, in which peptides often kink to place optimally anchoring side chains, MHC class II imposes an extended peptide conformation even at the cost of a highly conserved anchor residue. The substitution of Ser for Thr at p8 in the variant pigeon peptide induces no detectable surface change other than the loss of the side chain methyl group, despite the dramatic change in recognition by T cells. Finally, these structures can be used to interpret the many published mutational studies of these ligands and the T cell receptors that recognize them.

Structural basis of cytochrome c presentation by IE(k).,Fremont DH, Dai S, Chiang H, Crawford F, Marrack P, Kappler J J Exp Med. 2002 Apr 15;195(8):1043-52. PMID:11956295<ref>PMID:11956295</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
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<div class="pdbe-citations 1ktd" style="background-color:#fffaf0;"></div>

==See Also==
*[[MHC 3D structures|MHC 3D structures]]
*[[MHC II 3D structures|MHC II 3D structures]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Columba livia]]
[[Category: Large Structures]]
[[Category: Mus musculus]]
[[Category: Chiang H]]
[[Category: Crawford F]]
[[Category: Dai S]]
[[Category: Fremont DH]]
[[Category: Kappler J]]
[[Category: Marrack P]]