View source for 7umm


==H1 Solomon Islands 2006 hemagglutinin in complex with Ab109==
<StructureSection load='7umm' size='340' side='right'caption='[[7umm]], [[Resolution|resolution]] 3.36&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[7umm]] is a 9 chain structure with sequence from [https://en.wikipedia.org/wiki/Influenza_A_virus_(A/Solomon_Islands/3/2006(H1N1)) Influenza A virus (A/Solomon Islands/3/2006(H1N1))] and [https://en.wikipedia.org/wiki/Mus_musculus Mus musculus]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=7UMM OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=7UMM FirstGlance]. <br>
</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">Electron Microscopy, [[Resolution|Resolution]] 3.36&#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=7umm FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=7umm OCA], [https://pdbe.org/7umm PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=7umm RCSB], [https://www.ebi.ac.uk/pdbsum/7umm PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=7umm ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/A7Y8I1_9INFA A7Y8I1_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.[HAMAP-Rule:MF_04072][SAAS:SAAS01039073]  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]
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Pathogens evade host humoral responses by accumulating mutations in surface antigens. While variable, there are conserved regions that cannot mutate without compromising fitness. Antibodies targeting these conserved epitopes are often broadly protective but remain minor components of the repertoire. Rational immunogen design leverages a structural understanding of viral antigens to modulate humoral responses to favor these responses. Here, we report an epitope-enriched immunogen presenting a higher copy number of the influenza hemagglutinin (HA) receptor-binding site (RBS) epitope relative to other B cell epitopes. Immunization in a partially humanized murine model imprinted with an H1 influenza shows H1-specific serum and &gt;99% H1-specific B cells being RBS-directed. Single B cell analyses show a genetically restricted response that structural analysis defines as RBS-directed antibodies engaging the RBS with germline-encoded contacts. These data show how epitope enrichment expands B cell responses toward conserved epitopes and advances immunogen design approaches for next-generation viral vaccines.

An epitope-enriched immunogen expands responses to a conserved viral site.,Caradonna TM, Ronsard L, Yousif AS, Windsor IW, Hecht R, Bracamonte-Moreno T, Roffler AA, Maron MJ, Maurer DP, Feldman J, Marchiori E, Barnes RM, Rohrer D, Lonberg N, Oguin TH 3rd, Sempowski GD, Kepler TB, Kuraoka M, Lingwood D, Schmidt AG Cell Rep. 2022 Nov 8;41(6):111628. doi: 10.1016/j.celrep.2022.111628. PMID:36351401<ref>PMID:36351401</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 7umm" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Large Structures]]
[[Category: Mus musculus]]
[[Category: Caradonna TM]]
[[Category: Schmidt AG]]
[[Category: Windsor IW]]