View source for 1efx


==STRUCTURE OF A COMPLEX BETWEEN THE HUMAN NATURAL KILLER CELL RECEPTOR KIR2DL2 AND A CLASS I MHC LIGAND HLA-CW3==
<StructureSection load='1efx' size='340' side='right'caption='[[1efx]], [[Resolution|resolution]] 3.00&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[1efx]] is a 5 chain structure with sequence from [https://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1EFX OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1EFX 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]] 3&#8491;</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=1efx FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1efx OCA], [https://pdbe.org/1efx PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1efx RCSB], [https://www.ebi.ac.uk/pdbsum/1efx PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1efx ProSAT]</span></td></tr>
</table>
== Disease ==
[https://www.uniprot.org/uniprot/HLAC_HUMAN HLAC_HUMAN] B-lymphoblastic leukemia/lymphoma with t(9;22)(q34.1;q11.2). Disease susceptibility is associated with variants affecting the gene represented in this entry. Allele C*06:02 presents a melanocyte autoantigen ADAMTSL5 (VRSRRCLRL) to Valpha3S1/Vbeta13S1 TCR on CD8-positive T cells, and may trigger an autoimmune response against melanocytes.<ref>PMID:26621454</ref> 
== Function ==
[https://www.uniprot.org/uniprot/HLAC_HUMAN HLAC_HUMAN] Antigen-presenting major histocompatibility complex class I (MHCI) molecule with an important role in reproduction and antiviral immunity (PubMed:20972337, PubMed:24091323, PubMed:20439706, PubMed:11172028, PubMed:20104487, PubMed:28649982, PubMed:29312307). In complex with B2M/beta 2 microglobulin displays a restricted repertoire of self and viral peptides and acts as a dominant ligand for inhibitory and activating killer immunoglobulin receptors (KIRs) expressed on NK cells (PubMed:16141329). In an allogeneic setting, such as during pregnancy, mediates interaction of extravillous trophoblasts with KIR on uterine NK cells and regulate trophoblast invasion necessary for placentation and overall fetal growth (PubMed:20972337, PubMed:24091323). During viral infection, may present viral peptides with low affinity for KIRs, impeding KIR-mediated inhibition through peptide antagonism and favoring lysis of infected cells (PubMed:20439706). Presents a restricted repertoire of viral peptides on antigen-presenting cells for recognition by alpha-beta T cell receptor (TCR) on HLA-C-restricted CD8-positive T cells, guiding antigen-specific T cell immune response to eliminate infected cells, particularly in chronic viral infection settings such as HIV-1 or CMV infection (PubMed:11172028, PubMed:20104487, PubMed:28649982). Both the peptide and the MHC molecule are recognized by TCR, the peptide is responsible for the fine specificity of antigen recognition and MHC residues account for the MHC restriction of T cells (By similarity). Typically presents intracellular peptide antigens of 9 amino acids that arise from cytosolic proteolysis via proteasome. Can bind different peptides containing allele-specific binding motifs, which are mainly defined by anchor residues at position 2 and 9. Preferentially displays peptides having a restricted repertoire of hydrophobic or aromatic amino acids (Phe, Ile, Leu, Met, Val and Tyr) at the C-terminal anchor (PubMed:8265661, PubMed:25311805).[UniProtKB:P04439]<ref>PMID:11172028</ref> <ref>PMID:16141329</ref> <ref>PMID:20104487</ref> <ref>PMID:20439706</ref> <ref>PMID:20972337</ref> <ref>PMID:24091323</ref> <ref>PMID:25311805</ref> <ref>PMID:28649982</ref> <ref>PMID:29312307</ref> <ref>PMID:8265661</ref>   ALLELE C*01:02: The peptide-bound form interacts with KIR2DL2 and KIR2DL3 inhibitory receptors on NK cells. The low affinity peptides compete with the high affinity peptides impeding KIR-mediated inhibition and favoring lysis of infected cells (PubMed:20439706). Presents to CD8-positive T cells a CMV epitope derived from UL83/pp65 (RCPEMISVL), an immediate-early antigen necessary for initiating viral replication (PubMed:12947002).<ref>PMID:12947002</ref> <ref>PMID:20439706</ref>   ALLELE C*04:01: Presents a conserved HIV-1 epitope derived from env (SFNCGGEFF) to memory CD8-positive T cells, eliciting very strong IFNG responses (PubMed:20104487). Presents CMV epitope derived from UL83/pp65 (QYDPVAALF) to CD8-positive T cells, triggering T cell cytotoxic response (PubMed:12947002).<ref>PMID:12947002</ref> <ref>PMID:20104487</ref>   ALLELE C*05:01: Presents HIV-1 epitope derived from rev (SAEPVPLQL) to CD8-positive T cells, triggering T cell cytotoxic response.<ref>PMID:11172028</ref>   ALLELE C*06:02: In trophoblasts, interacts with KIR2DS2 on uterine NK cells and triggers NK cell activation, including secretion of cytokines such as GMCSF that enhances trophoblast migration.<ref>PMID:24091323</ref>   ALLELE C*07:02: Plays an important role in the control of chronic CMV infection. Presents immunodominant CMV epitopes derived from IE1 (LSEFCRVL and CRVLCCYVL) and UL28 (FRCPRRFCF), both antigens synthesized during immediate-early period of viral replication. Elicits a strong anti-viral CD8-positive T cell immune response that increases markedly with age.<ref>PMID:29312307</ref>   ALLELE C*08:01: Presents viral epitopes derived from CMV UL83 (VVCAHELVC) and IAV M1 (GILGFVFTL), triggering CD8-positive T cell cytotoxic response.<ref>PMID:12947002</ref> <ref>PMID:24990997</ref>   ALLELE C*12:02: Presents CMV epitope derived from UL83 (VAFTSHEHF) to CD8-positive T cells.<ref>PMID:12947002</ref>   ALLELE C*15:02: Presents CMV epitope derived from UL83 CC (VVCAHELVC) to CD8-positive T cells, triggering T cell cytotoxic response.<ref>PMID:12947002</ref> 
== 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/ef/1efx_consurf.spt"</scriptWhenChecked>
    <scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview01.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=1efx ConSurf].
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== Publication Abstract from PubMed ==
Target cell lysis is regulated by natural killer (NK) cell receptors that recognize class I MHC molecules. Here we report the crystal structure of the human immunoglobulin-like NK cell receptor KIR2DL2 in complex with its class I ligand HLA-Cw3 and peptide. KIR binds in a nearly orthogonal orientation across the alpha1 and alpha2 helices of Cw3 and directly contacts positions 7 and 8 of the peptide. No significant conformational changes in KIR occur on complex formation. The receptor footprint on HLA overlaps with but is distinct from that of the T-cell receptor. Charge complementarity dominates the KIR/HLA interface and mutations that disrupt interface salt bridges substantially diminish binding. Most contacts in the complex are between KIR and conserved HLA-C residues, but a hydrogen bond between Lys 44 of KIR2DL2 and Asn 80 of Cw3 confers the allotype specificity. KIR contact requires position 8 of the peptide to be a residue smaller than valine. A second KIR/HLA interface produced an ordered receptor-ligand aggregation in the crystal which may resemble receptor clustering during immune synapse formation.

Crystal structure of an NK cell immunoglobulin-like receptor in complex with its class I MHC ligand.,Boyington JC, Motyka SA, Schuck P, Brooks AG, Sun PD Nature. 2000 Jun 1;405(6786):537-43. PMID:10850706<ref>PMID:10850706</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 1efx" style="background-color:#fffaf0;"></div>

==See Also==
*[[Beta-2 microglobulin 3D structures|Beta-2 microglobulin 3D structures]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Homo sapiens]]
[[Category: Large Structures]]
[[Category: Boyington JC]]
[[Category: Brooks AG]]
[[Category: Motyka SA]]
[[Category: Schuck P]]
[[Category: Sun PD]]