6X3E

hEAAT3-Asymmetric-1o2i

6X3E の概要

• エントリーDOI: 10.2210/pdb6x3e/pdb
• EMDBエントリー: 22020
• 分子名称: Excitatory amino acid transporter 3, ASPARTIC ACID, SODIUM ION (3 entities in total)
• 機能のキーワード: asymmetric, outward-facing bound, inward-facing open, transport protein
• 由来する生物種: Homo sapiens (Human)
• タンパク質・核酸の鎖数: 3
• 化学式量合計: 172105.58

構造登録者

Qiu, B.,Matthies, D.,Boudker, O. (登録日: 2020-05-21, 公開日: 2021-03-17, 最終更新日: 2025-05-21)

主引用文献

Qiu, B.,Matthies, D.,Fortea, E.,Yu, Z.,Boudker, O.
Cryo-EM structures of excitatory amino acid transporter 3 visualize coupled substrate, sodium, and proton binding and transport.
Sci Adv, 7:-, 2021

PubMed Abstract: Human excitatory amino acid transporter 3 (hEAAT3) mediates glutamate uptake in neurons, intestine, and kidney. Here, we report cryo-EM structures of hEAAT3 in several functional states where the transporter is empty, bound to coupled sodium ions only, or fully loaded with three sodium ions, a proton, and the substrate aspartate. The structures suggest that hEAAT3 operates by an elevator mechanism involving three functionally independent subunits. When the substrate-binding site is near the cytoplasm, it has a remarkably low affinity for the substrate, perhaps facilitating its release and allowing the rapid transport turnover. The mechanism of the coupled uptake of the sodium ions and the substrate is conserved across evolutionarily distant families and is augmented by coupling to protons in EAATs. The structures further suggest a mechanism by which a conserved glutamate residue mediates proton symport.

PubMed: 33658209
DOI: 10.1126/sciadv.abf5814

実験手法

ELECTRON MICROSCOPY (3.42 Å)