View source for 9e65


==Cryo-EM structure of mechanosensitive channel YnaI A155V mutant in conformation 1==
<StructureSection load='9e65' size='340' side='right'caption='[[9e65]], [[Resolution|resolution]] 2.80&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[9e65]] is a 7 chain structure with sequence from [https://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=9E65 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=9E65 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]] 2.8&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=PTY:PHOSPHATIDYLETHANOLAMINE'>PTY</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=9e65 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=9e65 OCA], [https://pdbe.org/9e65 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=9e65 RCSB], [https://www.ebi.ac.uk/pdbsum/9e65 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=9e65 ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/YNAI_ECOLI YNAI_ECOLI] Mechanosensitive channel that protects cells against hypoosmotic stress when highly overexpressed.<ref>PMID:22874652</ref> 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
YnaI is a member of the family of bacterial MscS (mechanosensitive channel of small conductance)-like channels. Channel gating upon hypoosmotic stress and the role of lipids in this process have been extensively studied for MscS, but are less well understood for YnaI, which features two additional transmembrane helices. Here, we combined cryogenic electron microscopy, molecular dynamics simulations and patch-clamp electrophysiology to advance our understanding of YnaI. The two additional helices move the lipid-filled hydrophobic pockets in YnaI further away from the lipid bilayer and change the function of the pocket lipids from being a critical gating element in MscS to being more of a structural element in YnaI. Unlike MscS, YnaI shows pronounced gating hysteresis and remains open to a substantially lower membrane tension than is needed to initially open the channel. Thus, at near-lytic membrane tension, both MscL and YnaI will open, but while MscL has a large pore and must close quickly to minimize loss of essential metabolites, YnaI only conducts ions and can thus remain open for longer to continue to facilitate pressure equilibration across the membrane.

Lipid interactions and gating hysteresis suggest a physiological role for mechanosensitive channel YnaI.,Will N, Hiotis G, Nakayama Y, Angiulli G, Zhou Z, Cox CD, Martinac B, Walz T Nat Commun. 2025 Aug 12;16(1):7472. doi: 10.1038/s41467-025-62805-8. PMID:40796571<ref>PMID:40796571</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 9e65" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Escherichia coli]]
[[Category: Large Structures]]
[[Category: Hiotis G]]
[[Category: Walz T]]
[[Category: Will N]]