8HIW

AtALMT9 in the apo state

8HIW の概要

• エントリーDOI: 10.2210/pdb8hiw/pdb
• EMDBエントリー: 34828
• 分子名称: Aluminum-activated malate transporter 9, CITRIC ACID (2 entities in total)
• 機能のキーワード: channel, transport protein
• 由来する生物種: Arabidopsis thaliana (thale cress)
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 134434.14

構造登録者

Gong, D.S. (登録日: 2022-11-22, 公開日: 2024-03-06, 最終更新日: 2024-09-25)

主引用文献

Qian, D.,Chai, Y.,Li, W.,Cui, B.,Lin, S.,Wang, Z.,Wang, C.,Qu, L.Q.,Gong, D.
Structural insight into the Arabidopsis vacuolar anion channel ALMT9 shows clade specificity.
Cell Rep, 43:114731-114731, 2024

PubMed Abstract: The Arabidopsis thaliana aluminum-activated malate transporter 9 (AtALMT9) functions as a vacuolar chloride channel that regulates the stomatal aperture. Here, we present the cryoelectron microscopy (cryo-EM) structures of AtALMT9 in three distinct states. AtALMT9 forms a dimer, and the pore is lined with four positively charged rings. The apo-AtALMT9 state shows a putative endogenous citrate obstructing the pore, where two W120 constriction residues enclose a gate with a pore radius of approximately 1.8 Å, representing an open state. Interestingly, channel closure is solely controlled by W120. Compared to wild-type plants, the W120A mutant exhibits more sensitivity to drought stress and is unable to restore the visual phenotype on leaves upon water recovery, reflecting persistent stomatal opening. Furthermore, notable variations are noted in channel gating and substrate recognition of Glycine max ALMT12, AtALMT9, and AtALMT1. In summary, our investigation enhances comprehension of the interplay between structure and function within the ALMT family.

PubMed: 39269901
DOI: 10.1016/j.celrep.2024.114731

実験手法

ELECTRON MICROSCOPY (3.34 Å)