9E63

Cryo-EM structure of mechanosensitive channel YnaI in DOPC nanodiscs treated with beta-cyclodextrin

9E63 の概要

• エントリーDOI: 10.2210/pdb9e63/pdb
• 関連するPDBエントリー: 9E62
• EMDBエントリー: 47547 47548
• 分子名称: Low conductance mechanosensitive channel YnaI, PHOSPHATIDYLETHANOLAMINE (2 entities in total)
• 機能のキーワード: mechanosensitive, membrane protein
• 由来する生物種: Escherichia coli
• タンパク質・核酸の鎖数: 7
• 化学式量合計: 304034.96

構造登録者

Hiotis, G.,Will, N.,Walz, T. (登録日: 2024-10-29, 公開日: 2025-08-27)

主引用文献

Will, N.,Hiotis, G.,Nakayama, Y.,Angiulli, G.,Zhou, Z.,Cox, C.D.,Martinac, B.,Walz, T.
Lipid interactions and gating hysteresis suggest a physiological role for mechanosensitive channel YnaI.
Nat Commun, 16:7472-7472, 2025

PubMed Abstract: 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.

PubMed: 40796571
DOI: 10.1038/s41467-025-62805-8

実験手法

ELECTRON MICROSCOPY (2.3 Å)