STRUCTURAL MECHANISM OF IONIC CONDUCTIVITY OF THE TRPV1 CHANNEL

Yu. A. Trofimov; Трофимов Ю. А.; A. S. Minakov; Минаков А. С.; N. A. Krylov; Крылов Н. А.; R. G. Efremov; Ефремов Р. Г.

doi:10.31857/S2686738923700221

STRUCTURAL MECHANISM OF IONIC CONDUCTIVITY OF THE TRPV1 CHANNEL

Authors: Trofimov Y.A.¹^,2, Minakov A.S.³, Krylov N.A.¹^,4, Efremov R.G.¹^,4^,5
Affiliations:
1. Shemyakin & Ovchinnikov Institute of Bioorganic Chemistry of the Russian Academy of Sciences
2. National Research Nuclear University MEPhI (Moscow Engineering Physics Institute)
3. Lomonosov Moscow State University
4. National Research University Higher School of Economics
5. Moscow Institute of Physics and Technology
Issue: Vol 510, No 1 (2023)
Pages: 247-251
Section: Articles
URL: https://journals.rcsi.science/2686-7389/article/view/135691
DOI: https://doi.org/10.31857/S2686738923700221
EDN: https://elibrary.ru/QIDHBZ
ID: 135691

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Abstract

The so-called “hydrophobic gating” is widely discussed as a putative mechanism to control water and ion conduction via ion channels. This effect can occur in narrow areas of the channels pore lined by non-polar residues. In the closed state of the channel, such regions may spontaneously transit to a dehydrated state to block water and ions transport without full pore occlusion. In the open state, the hydrophobic gate is wide enough to provide sustainable hydration and conduction. Apparently, the transport through the open hydrophobic gate may by facilitated by some polar residues that assist polar/charged substances to overcome the energy barrier created by nonpolar environment. In this work, we investigated the behavior of Na⁺ ions and their hydration shells in the open pore of the rat TRPV1 ion channel by molecular dynamics simulations. We show that polar protein groups coordinate water molecules in such a way as to restore the hydration shell of ions in the hydrophobic gate that ensures ion transport through the gate in a fully hydrated state.

Keywords

TRPV1, ion channels, hydrophobic gate, ionic conductivity

References

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