8J7U

Cryo-EM structure of hZnT7-Fab complex in zinc-bound state, determined in outward-facing conformation

8J7U の概要

• エントリーDOI: 10.2210/pdb8j7u/pdb
• EMDBエントリー: 36049
• 分子名称: Zinc transporter 7, Heavy chain of YN7114-08 Fab, Light chain of YN7114-08 Fab, ... (4 entities in total)
• 機能のキーワード: zinc, proton, transporter, golgi apparatus, metal transporter, histidine-rich loop, metal transport
• 由来する生物種: Homo sapiens (human); 詳細
• タンパク質・核酸の鎖数: 6
• 化学式量合計: 184368.72

構造登録者

Han, B.B.,Inaba, K.,Watanabe, S. (登録日: 2023-04-28, 公開日: 2023-09-20)

主引用文献

Bui, H.B.,Watanabe, S.,Nomura, N.,Liu, K.,Uemura, T.,Inoue, M.,Tsutsumi, A.,Fujita, H.,Kinoshita, K.,Kato, Y.,Iwata, S.,Kikkawa, M.,Inaba, K.
Cryo-EM structures of human zinc transporter ZnT7 reveal the mechanism of Zn 2+ uptake into the Golgi apparatus.
Nat Commun, 14:4770-4770, 2023

PubMed Abstract: Zinc ions (Zn) are vital to most cells, with the intracellular concentrations of Zn being tightly regulated by multiple zinc transporters located at the plasma and organelle membranes. We herein present the 2.2-3.1 Å-resolution cryo-EM structures of a Golgi-localized human Zn/H antiporter ZnT7 (hZnT7) in Zn-bound and unbound forms. Cryo-EM analyses show that hZnT7 exists as a dimer via tight interactions in both the cytosolic and transmembrane (TM) domains of two protomers, each of which contains a single Zn-binding site in its TM domain. hZnT7 undergoes a TM-helix rearrangement to create a negatively charged cytosolic cavity for Zn entry in the inward-facing conformation and widens the luminal cavity for Zn release in the outward-facing conformation. An exceptionally long cytosolic histidine-rich loop characteristic of hZnT7 binds two Zn ions, seemingly facilitating Zn recruitment to the TM metal transport pathway. These structures permit mechanisms of hZnT7-mediated Zn uptake into the Golgi to be proposed.

PubMed: 37553324
DOI: 10.1038/s41467-023-40521-5

実験手法

ELECTRON MICROSCOPY (3.12 Å)