Download MendeleyInteraction of Tarantula Venom Peptide ProTx-II with Lipid Membranes Is a Prerequisite for Its Inhibition of Human Voltage-gated Sodium Channel NaV1.7.
Henriques, S.T., Deplazes, E., Lawrence, N., Cheneval, O., Chaousis, S., Inserra, M., Thongyoo, P., King, G.F., Mark, A.E., Vetter, I., Craik, D.J., Schroeder, C.I.(2016) J Biol Chem 291: 17049-17065
- PubMed: 27311819
- DOI: https://doi.org/10.1074/jbc.M116.729095
- Primary Citation of Related Structures:
2N9T - PubMed Abstract:
ProTx-II is a disulfide-rich peptide toxin from tarantula venom able to inhibit the human voltage-gated sodium channel 1.7 (hNaV1.7), a channel reported to be involved in nociception, and thus it might have potential as a pain therapeutic. ProTx-II acts by binding to the membrane-embedded voltage sensor domain of hNaV1.7, but the precise peptide channel-binding site and the importance of membrane binding on the inhibitory activity of ProTx-II remain unknown. In this study, we examined the structure and membrane-binding properties of ProTx-II and several analogues using NMR spectroscopy, surface plasmon resonance, fluorescence spectroscopy, and molecular dynamics simulations. Our results show a direct correlation between ProTx-II membrane binding affinity and its potency as an hNaV1.7 channel inhibitor. The data support a model whereby a hydrophobic patch on the ProTx-II surface anchors the molecule at the cell surface in a position that optimizes interaction of the peptide with the binding site on the voltage sensor domain. This is the first study to demonstrate that binding of ProTx-II to the lipid membrane is directly linked to its potency as an hNaV1.7 channel inhibitor.
Organizational Affiliation:
From the Institute for Molecular Bioscience and s.henriques@uq.edu.au.
