9KHF

AtGORK Full length 1

9KHF の概要

• エントリーDOI: 10.2210/pdb9khf/pdb
• EMDBエントリー: 62338
• 分子名称: Potassium channel GORK, POTASSIUM ION (2 entities in total)
• 機能のキーワード: complex, transport protein, proton transport
• 由来する生物種: Arabidopsis thaliana (thale cress)
• タンパク質・核酸の鎖数: 4
• 化学式量合計: 350693.88

構造登録者

Chen, Y.H.,Li, Q.Y.,Zhang, C.R.,Tang, L.H. (登録日: 2024-11-10, 公開日: 2025-10-29, 最終更新日: 2026-01-07)

主引用文献

Li, Q.Y.,Qin, L.,Tang, L.H.,Zhang, C.R.,Huang, S.,Wang, K.,Zhang, G.H.,Hao, N.J.,Xiao, Q.,Niu, T.,Su, M.,Hedrich, R.,Chen, Y.H.
Structural and mechanistic insights into symmetry conversion in plant GORK K+ channel regulation.
Protein Cell, 16:1035-1047, 2025

PubMed Abstract: GORK is a shaker-like potassium channel in plants that contains ankyrin (ANK) repeats. In guard cells, activation of GORK causes K+ efflux, reducing turgor pressure and closing stomata. However, how GORK is regulated remains largely elusive. Here, we solved the cryo-EM structure of Arabidopsis GORK, revealing an unusual symmetry reduction (from C4 to C2) feature within its tetrameric assembly. This symmetry reduction in GORK channel is driven by ANK dimerization, which disrupts the coupling between transmembrane helices and cytoplasmic domains, thus maintaining GORK in an autoinhibited state. Electrophysiological and structural analyses further confirmed that ANK dimerization inhibits GORK, and its removal restores C4 symmetry, converting GORK to an activatable state. This dynamic switching between C2 and C4 symmetry, mediated by ANK dimerization, presents a GORK target site that guard cells regulate to switch the plant K+ channel between inhibited and activatable states, thus controlling stomatal movement in response to environmental stimuli.

PubMed: 40996076
DOI: 10.1093/procel/pwaf067

実験手法

ELECTRON MICROSCOPY (3.4 Å)