+Search query
-Structure paper
Title | High-affinity agonism at the P2X receptor is mediated by three residues outside the orthosteric pocket. |
---|---|
Journal, issue, pages | Nat Commun, Vol. 15, Issue 1, Page 6662, Year 2024 |
Publish date | Aug 6, 2024 |
Authors | Adam C Oken / Nicolas E Lisi / Ipsita Krishnamurthy / Alanna E McCarthy / Michael H Godsey / Arthur Glasfeld / Steven E Mansoor / |
PubMed Abstract | P2X receptors are trimeric ATP-gated ion channels that activate diverse signaling cascades. Due to its role in apoptotic pathways, selective activation of P2X is a potential experimental tool and ...P2X receptors are trimeric ATP-gated ion channels that activate diverse signaling cascades. Due to its role in apoptotic pathways, selective activation of P2X is a potential experimental tool and therapeutic approach in cancer biology. However, mechanisms of high-affinity P2X activation have not been defined. We report high-resolution cryo-EM structures of wild-type rat P2X bound to the high-affinity agonist BzATP as well as significantly improved apo receptor structures in the presence and absence of sodium. Apo structures define molecular details of pore architecture and reveal how a partially hydrated Na ion interacts with the conductance pathway in the closed state. Structural, electrophysiological, and direct binding data of BzATP reveal that three residues just outside the orthosteric ATP-binding site are responsible for its high-affinity agonism. This work provides insights into high-affinity agonism for any P2X receptor and lays the groundwork for development of subtype-specific agonists applicable to cancer therapeutics. |
External links | Nat Commun / PubMed:39107314 / PubMed Central |
Methods | EM (single particle) |
Resolution | 2.49 - 2.78 Å |
Structure data | EMDB-41570, PDB-8tr5: EMDB-41581, PDB-8trj: EMDB-42976, PDB-8v4s: |
Chemicals | ChemComp-GDP: ChemComp-ZN: ChemComp-NAG: ChemComp-PLM: ChemComp-NA: ChemComp-HOH:
ChemComp-KD9: |
Source |
|
Keywords | MEMBRANE PROTEIN / Ion Channel / Ligand-gate Ion Channel / P2X Receptor / Allosteric Antagonist / High-Affinity Agonist |