9QSZ

Cryo-EM structure of aquaporin 3 at pH 8.0 with hydrogen peroxide

9QSZ の概要

• エントリーDOI: 10.2210/pdb9qsz/pdb
• EMDBエントリー: 53345
• 分子名称: Aquaporin-3, HYDROGEN PEROXIDE (3 entities in total)
• 機能のキーワード: membrane protein, glycerol channel, hydrogen peroxide transport, tetramer
• 由来する生物種: Homo sapiens (human)
• タンパク質・核酸の鎖数: 4
• 化学式量合計: 130130.44

構造登録者

Huang, P.,Venskutonyte, R.,Lindkvist-Petersson, K. (登録日: 2025-04-07, 公開日: 2026-02-18)

主引用文献

Huang, P.,Venskutonyte, R.,Wilson, C.J.,Bsharat, S.,Prasad, R.B.,Gourdon, P.,Artner, I.,de Groot, B.L.,Lindkvist-Petersson, K.
Structural insights into AQP3 channel closure upon pH and redox changes reveal an autoregulatory molecular mechanism.
Nat Commun, 16:10997-10997, 2025

PubMed Abstract: Regulation of intracellular levels of reactive oxygen species (ROS) remains poorly understood. Aquaporin 3 (AQP3) facilitates the membrane transport of hydrogen peroxide (HO), a key ROS signaling molecule. Here we elucidate the molecular mechanism of AQP3 and show that its regulatory properties are both pH dependent and autoregulated by HO. Using single particle cryo-electron microscopy, we present open and closed conformations of human AQP3. At pH 8.0, the channel adopts an open state, while acidic pH or exposure to HO promotes closure via a large conformational rearrangement of extracellular loop E. These findings reveal a mechanism for autoregulation of HO transport and establish AQP3 as a key modulator of redox homeostasis in human pancreatic β-cells.

PubMed: 41429774
DOI: 10.1038/s41467-025-67144-2

実験手法

ELECTRON MICROSCOPY (3 Å)