Download MendeleyHigh-affinity agonism at the P2X 7 receptor is mediated by three residues outside the orthosteric pocket.
Oken, A.C., Lisi, N.E., Krishnamurthy, I., McCarthy, A.E., Godsey, M.H., Glasfeld, A., Mansoor, S.E.(2024) Nat Commun 15: 6662-6662
- PubMed: 39107314
- DOI: https://doi.org/10.1038/s41467-024-50771-6
- Primary Citation of Related Structures:
8TR5, 8TRJ, 8V4S - 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 7 is a potential experimental tool and therapeutic approach in cancer biology. However, mechanisms of high-affinity P2X 7 activation have not been defined. We report high-resolution cryo-EM structures of wild-type rat P2X 7 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.
Organizational Affiliation:
Department of Chemical Physiology & Biochemistry, Oregon Health & Science University, Portland, OR, 97239, USA.
