Download MendeleyDiverse binding poses of agonistic neurotoxins on human Na v 1.6.
Fan, X., Huang, J., Yang, L., Chen, J., Wang, H., Huang, X., Geng, J., Wu, Q., Xie, Y., Lu, F., Guo, Q., Shen, Z., Jin, X., Yan, N.(2026) Nature
- PubMed: 42271061 Search on PubMedSearch on PubMed Central
- DOI: https://doi.org/10.1038/s41586-026-10661-x
- Primary Citation Related Structures:
25IH, 25II, 25IJ - PubMed Abstract:
Voltage-gated sodium (Na v ) channels are key targets of various venomous toxins. Deciphering the binding poses and mechanisms of action of representative toxins will help to dissect the functional mechanism of the channels and facilitate therapeutic development targeting Na v channels 1,2 . Here we present cryo-electron microscopy (cryo-EM) structures of distinct binding poses of three agonistic peptide toxins on the human Na v 1.6-β1 channel complex. The globular β-scorpion toxin Cn2 nestles between the extracellular segment of voltage-sensing domain (VSD) in the second repeat of the Na v 1.6 core α-unit (VSD II ) and the pore extracellular loops in the third repeat of the Na v 1.6 core α-unit (ECL III ), where it is stabilized by interactions with both protein regions and the branched N1372-glycan. Cone snail ι-conotoxin RXIA adopts an elongated conformation, spanning VSD I and VSD IV to wrap around the shoulder of the pore domain (PD). The bullet ant-derived toxin δ-paraponeritoxin-Pc1a exists as a transmembrane helix that stands between VSD II and PD III . Our findings, corroborated by functional characterizations, illustrate the diversity in peptide toxin binding poses and mechanisms of action, link stabilization of the up state of VSD I or VSD II to channel activation, and provide clues to the rational design of selective Na v channel modulators.
- Institute of Bio-Architecture and Bio-Interactions (IBABI), Shenzhen Medical Academy of Research and Translation, Shenzhen, China.
Organizational Affiliation:
