View source for 2n54


==Solution structure of a disulfide stabilized XCL1 dimer==
<StructureSection load='2n54' size='340' side='right'caption='[[2n54]]' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[2n54]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens]. Full experimental information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2N54 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=2N54 FirstGlance]. <br>
</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">Solution NMR, 20 models</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=2n54 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2n54 OCA], [https://pdbe.org/2n54 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=2n54 RCSB], [https://www.ebi.ac.uk/pdbsum/2n54 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=2n54 ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/XCL1_HUMAN XCL1_HUMAN] Chemotactic activity for lymphocytes but not for monocytes or neutrophils.
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Unlike other chemokines, XCL1 undergoes a distinct metamorphic interconversion between a canonical monomeric chemokine fold and a unique beta-sandwich dimer. The monomeric conformation binds and activates the receptor XCR1, whereas the dimer binds extracellular matrix glycosaminoglycans and has been associated with anti-human immunodeficiency virus (HIV) activity. Functional studies of WT-XCL1 are complex, as both conformations are populated in solution. To overcome this limitation, we engineered a stabilized dimeric variant of XCL1 designated CC5. This variant features a new disulfide bond (A36C-A49C) that prevents structural interconversion by locking the chemokine into the beta-sandwich dimeric conformation, as demonstrated by NMR structural analysis and hydrogen/deuterium exchange experiments. Functional studies analyzing glycosaminoglycan binding demonstrate that CC5 binds with high affinity to heparin. In addition, CC5 exhibits potent inhibition of HIV-1 activity in primary peripheral blood mononuclear cells (PBMCs), demonstrating the importance of the dimer in blocking viral infection. Conformational variants like CC5 are valuable tools for elucidating the biological relevance of the XCL1 native-state interconversion and will assist in future antiviral and functional studies.

Engineering Metamorphic Chemokine Lymphotactin/XCL1 into the GAG-Binding, HIV-Inhibitory Dimer Conformation.,Fox JC, Tyler RC, Guzzo C, Tuinstra RL, Peterson FC, Lusso P, Volkman BF ACS Chem Biol. 2015 Sep 2. PMID:26302421<ref>PMID:26302421</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 2n54" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Homo sapiens]]
[[Category: Large Structures]]
[[Category: Peterson FF]]
[[Category: Tuinstra RL]]
[[Category: Tyler RC]]
[[Category: Volkman BF]]