View source for 6pd3


==Crystal Structure of a H5N1 influenza virus hemagglutinin at pH 5.5==
<StructureSection load='6pd3' size='340' side='right'caption='[[6pd3]], [[Resolution|resolution]] 2.30&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[6pd3]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Influenza_A_virus_(A/chicken/Vietnam/4/2003(H5N1)) Influenza A virus (A/chicken/Vietnam/4/2003(H5N1))]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=6PD3 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=6PD3 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]] 2.3&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=GOL:GLYCEROL'>GOL</scene>, <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=6pd3 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=6pd3 OCA], [https://pdbe.org/6pd3 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=6pd3 RCSB], [https://www.ebi.ac.uk/pdbsum/6pd3 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=6pd3 ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/Q1KHJ8_9INFA Q1KHJ8_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 either through clathrin-dependent endocytosis or through 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.[SAAS:SAAS01039674]  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.[RuleBase:RU003324]
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== Publication Abstract from PubMed ==
Hemagglutnin (HA) mediates entry of influenza virus through a series of conformational changes triggered by the low pH of the endosome. The residue or combination of residues acting as pH sensors has not yet been fully elucidated. In this work, we assay pH effects on the structure of H5 HA by soaking HA crystallized at pH 6.5 in a series of buffers with lower pH, mimicking the conditions of the endosome. We find that HA1-H38, which is conserved in Group 1 HA, undergoes a striking change in side chain conformation, which we attribute to its protonation and cation-cation repulsion with conserved HA1-H18. This work suggests that x-ray crystallography can be applied for studying small-scale pH-induced conformational changes providing valuable information on the location of pH sensors in HA. Importantly, the observed change in HA1-H38 conformation is further evidence that the pH-induced conformational changes of HA are the result of a series of protonation events to conserved and non-conserved pH sensors.

Identification of a pH sensor in Influenza hemagglutinin using X-ray crystallography.,Antanasijevic A, Durst MA, Lavie A, Caffrey M J Struct Biol. 2019 Nov 2:107412. doi: 10.1016/j.jsb.2019.107412. PMID:31689502<ref>PMID:31689502</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 6pd3" style="background-color:#fffaf0;"></div>

==See Also==
*[[Hemagglutinin 3D structures|Hemagglutinin 3D structures]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Large Structures]]
[[Category: Antanasijevic A]]
[[Category: Caffrey M]]
[[Category: Durst MA]]
[[Category: Lavie A]]