View source for 6icw


==Crystal structure of H7 hemagglutinin mutant AH-SGTQ (A138S, V186G, P221T and L226Q) from the influenza virus A/Anhui/1/2013 (H7N9)==
<StructureSection load='6icw' size='340' side='right'caption='[[6icw]], [[Resolution|resolution]] 2.60&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[6icw]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Influenza_A_virus Influenza A virus]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=6ICW OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=6ICW 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]] 2.6&#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></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=6icw FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=6icw OCA], [https://pdbe.org/6icw PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=6icw RCSB], [https://www.ebi.ac.uk/pdbsum/6icw PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=6icw 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 ==
Since 2013, H7N9 avian influenza viruses (AIVs) have caused more than 1,600 human infections, posing a threat to public health. An emerging concern is whether H7N9 AIVs will cause pandemics among humans. Molecular analysis of hemagglutinin (HA), which is a critical determinant of interspecies transmission, shows that the current H7N9 AIVs are still dual-receptor tropic, indicating limited human-to-human transmission potency. Mutagenesis and structural studies reveal that a G186V substitution is sufficient for H7N9 AIVs to acquire human receptor-binding capacity, and a Q226L substitution would favor binding to both avian and human receptors only when paired with A138/V186/P221 hydrophobic residues. These data suggest a different evolutionary route of H7N9 viruses compared to other AIV-subtype HAs.

Avian-to-Human Receptor-Binding Adaptation of Avian H7N9 Influenza Virus Hemagglutinin.,Xu Y, Peng R, Zhang W, Qi J, Song H, Liu S, Wang H, Wang M, Xiao H, Fu L, Fan Z, Bi Y, Yan J, Shi Y, Gao GF Cell Rep. 2019 Nov 19;29(8):2217-2228.e5. doi: 10.1016/j.celrep.2019.10.047. PMID:31747596<ref>PMID:31747596</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 6icw" style="background-color:#fffaf0;"></div>

==See Also==
*[[Hemagglutinin 3D structures|Hemagglutinin 3D structures]]
== References ==
<references/>
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</StructureSection>
[[Category: Influenza A virus]]
[[Category: Large Structures]]
[[Category: Gao GF]]
[[Category: Xu Y]]