7WSW

Cryo-EM structure of the Potassium channel AKT1 from Arabidopsis thaliana

7WSW の概要

• エントリーDOI: 10.2210/pdb7wsw/pdb
• EMDBエントリー: 32769
• 分子名称: Potassium channel AKT1, PHOSPHATIDYLETHANOLAMINE, POTASSIUM ION (3 entities in total)
• 機能のキーワード: complex, potassium channel, membrane protein
• 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: 400709.20

構造登録者

Yang, G.H.,Lu, Y.M.,Zhang, Y.M.,Jia, Y.T.,Li, X.M.,Lei, J.L. (登録日: 2022-02-02, 公開日: 2022-11-09)

主引用文献

Lu, Y.,Yu, M.,Jia, Y.,Yang, F.,Zhang, Y.,Xu, X.,Li, X.,Yang, F.,Lei, J.,Wang, Y.,Yang, G.
Structural basis for the activity regulation of a potassium channel AKT1 from Arabidopsis.
Nat Commun, 13:5682-5682, 2022

PubMed Abstract: The voltage-gated potassium channel AKT1 is responsible for primary K uptake in Arabidopsis roots. AKT1 is functionally activated through phosphorylation and negatively regulated by a potassium channel α-subunit AtKC1. However, the molecular basis for the modulation mechanism remains unclear. Here we report the structures of AKT1, phosphorylated-AKT1, a constitutively-active variant, and AKT1-AtKC1 complex. AKT1 is assembled in 2-fold symmetry at the cytoplasmic domain. Such organization appears to sterically hinder the reorientation of C-linkers during ion permeation. Phosphorylated-AKT1 adopts an alternate 4-fold symmetric conformation at cytoplasmic domain, which indicates conformational changes associated with symmetry switch during channel activation. To corroborate this finding, we perform structure-guided mutagenesis to disrupt the dimeric interface and identify a constitutively-active variant Asp379Ala mediates K permeation independently of phosphorylation. This variant predominantly adopts a 4-fold symmetric conformation. Furthermore, the AKT1-AtKC1 complex assembles in 2-fold symmetry. Together, our work reveals structural insight into the regulatory mechanism for AKT1.

PubMed: 36167696
DOI: 10.1038/s41467-022-33420-8

実験手法

ELECTRON MICROSCOPY (3.4 Å)