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Updated: Jun 6, 2026
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Proteomics to Identify Proteins Interacting with P2X2 Ligand-Gated Cation Channels
Published on: May 18, 2009
Structural basis for a central permeation pathway in the P2X1 receptor
Heng Zhang1, Pengpeng Wu1,2, Zhiyong Gu1,2
1The State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China.
Cell Discovery
|June 4, 2026
Summary
High-resolution structures of the P2X1 receptor reveal its central ion permeation pathway. A novel inhibitor binding site within this pathway offers potential for designing targeted P2X1 receptor inhibitors.
Area of Science:
- Structural Biology
- Molecular Biophysics
- Pharmacology
Background:
- The P2X1 receptor, an ATP-gated ion channel, is vital for platelet activation, thrombosis, and male infertility.
- Understanding the structural basis of ion permeation in P2X1 receptors is crucial but remains incomplete.
Purpose of the Study:
- To elucidate the high-resolution structure of the P2X1 receptor.
- To characterize the ion permeation pathway and identify key structural features.
- To discover novel inhibitor-binding sites within the P2X1 receptor.
Main Methods:
- High-resolution cryo-electron microscopy (cryo-EM) was employed to determine P2X1 receptor structures.
- Analysis of the cryo-EM structures identified ion coordination sites and a selectivity filter.
- Inhibition assays were performed to assess the effect of 3,5-bis(trifluoromethyl)aniline on cation flux.
Main Results:
- The study reveals a central ion permeation pathway extending through the P2X1 receptor's extracellular domain.
- An aspartate ring was identified as a selectivity filter, coordinating hydrated calcium ions.
- A small molecule, 3,5-bis(trifluoromethyl)aniline, was found to bind in the central vestibule, inhibiting cation flux.
Conclusions:
- The P2X1 receptor possesses a distinct central ion permeation pathway, expanding knowledge of P2X receptor architecture.
- A novel inhibitor-binding site at the top of the central vestibule was discovered.
- These structural insights facilitate the rational design of subtype-specific P2X1 receptor inhibitors.
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