4P1A

Thallium-bound inward-facing state of the glutamate transporter homologue GltPh

4P1A の概要

• エントリーDOI: 10.2210/pdb4p1a/pdb
• 関連するPDBエントリー: 1XZH 2NWL 2NWW 2NWX 3KBC 3V8F 3V8G 4IZM 4P19
• 分子名称: GltPh, THALLIUM (I) ION, MERCURY (II) ION (3 entities in total)
• 機能のキーワード: membrane protein, sodium-couple, asparate transporter, inward-facing state, thallium binding sites, transport protein
• 由来する生物種: Pyrococcus horikoshii
• タンパク質・核酸の鎖数: 3
• 化学式量合計: 135675.80

構造登録者

Verdon, G.,Boudker, O. (登録日: 2014-02-25, 公開日: 2014-06-04, 最終更新日: 2023-12-20)

主引用文献

Verdon, G.,Oh, S.,Serio, R.N.,Boudker, O.
Coupled ion binding and structural transitions along the transport cycle of glutamate transporters.
Elife, 3:e02283-e02283, 2014

PubMed Abstract: Membrane transporters that clear the neurotransmitter glutamate from synapses are driven by symport of sodium ions and counter-transport of a potassium ion. Previous crystal structures of a homologous archaeal sodium and aspartate symporter showed that a dedicated transport domain carries the substrate and ions across the membrane. Here, we report new crystal structures of this homologue in ligand-free and ions-only bound outward- and inward-facing conformations. We show that after ligand release, the apo transport domain adopts a compact and occluded conformation that can traverse the membrane, completing the transport cycle. Sodium binding primes the transport domain to accept its substrate and triggers extracellular gate opening, which prevents inward domain translocation until substrate binding takes place. Furthermore, we describe a new cation-binding site ideally suited to bind a counter-transported ion. We suggest that potassium binding at this site stabilizes the translocation-competent conformation of the unloaded transport domain in mammalian homologues.DOI: http://dx.doi.org/10.7554/eLife.02283.001.

PubMed: 24842876
DOI: 10.7554/eLife.02283

実験手法

X-RAY DIFFRACTION (3.75 Å)