View source for 4n63


==Crystal structure of hemagglutinin from an H7N9 influenza virus in complex with an O-linked glycan receptor==
<StructureSection load='4n63' size='340' side='right'caption='[[4n63]], [[Resolution|resolution]] 2.75&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[4n63]] is a 4 chain structure with sequence from [https://en.wikipedia.org/wiki/Influenza_A_virus_(A/Shanghai/02/2013(H7N9)) Influenza A virus (A/Shanghai/02/2013(H7N9))]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4N63 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=4N63 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]] 2.7522&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=GAL:BETA-D-GALACTOSE'>GAL</scene>, <scene name='pdbligand=NAG:N-ACETYL-D-GLUCOSAMINE'>NAG</scene>, <scene name='pdbligand=NGA:N-ACETYL-D-GALACTOSAMINE'>NGA</scene>, <scene name='pdbligand=SIA:O-SIALIC+ACID'>SIA</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=4n63 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4n63 OCA], [https://pdbe.org/4n63 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=4n63 RCSB], [https://www.ebi.ac.uk/pdbsum/4n63 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=4n63 ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/R4NN21_9INFA R4NN21_9INFA] Binds to sialic acid-containing receptors on the cell surface, bringing about the attachment of the virus particle to the cell. This attachment induces virion internalization of about two third of the virus particles through clathrin-dependent endocytosis and about one third through a clathrin- and caveolin-independent pathway. Plays a major role in the determination of host range restriction and virulence. Class I viral fusion protein. Responsible for penetration of the virus into the cell cytoplasm by mediating the fusion of the membrane of the endocytosed virus particle with the endosomal membrane. Low pH in endosomes induces an irreversible conformational change in HA2, releasing the fusion hydrophobic peptide. Several trimers are required to form a competent fusion pore (By similarity).[RuleBase:RU003324][SAAS:SAAS008980_004_327643]
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== Publication Abstract from PubMed ==
The 2013 outbreak of avian-origin H7N9 influenza in eastern China has raised concerns about its ability to transmit in the human population. The hemagglutinin glycoprotein of most human H7N9 viruses carries Leu(226), a residue linked to adaptation of H2N2 and H3N2 pandemic viruses to human receptors. However, glycan array analysis of the H7 hemagglutinin reveals negligible binding to humanlike alpha2-6-linked receptors and strong preference for a subset of avian-like alpha2-3-linked glycans recognized by all avian H7 viruses. Crystal structures of H7N9 hemagglutinin and six hemagglutinin-glycan complexes have elucidated the structural basis for preferential recognition of avian-like receptors. These findings suggest that the current human H7N9 viruses are poorly adapted for efficient human-to-human transmission.

Preferential recognition of avian-like receptors in human influenza A H7N9 viruses.,Xu R, de Vries RP, Zhu X, Nycholat CM, McBride R, Yu W, Paulson JC, Wilson IA Science. 2013 Dec 6;342(6163):1230-5. doi: 10.1126/science.1243761. PMID:24311689<ref>PMID:24311689</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 4n63" style="background-color:#fffaf0;"></div>

==See Also==
*[[Hemagglutinin 3D structures|Hemagglutinin 3D structures]]
== References ==
<references/>
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</StructureSection>
[[Category: Large Structures]]
[[Category: Wilson IA]]
[[Category: Xu R]]