Structural mechanism of ionic conductivity of the TRPV1 channel

Doklady Biochemistry and Biophysics. 2023. Vol. 508. No. 1. P. 1–5.

Trofimov Y. A., Minakov A. S., Krylov N. A., Efremov R.

In many types of ion channels, certain internal surface areas of their transmembrane pores are lined with non-polar residues forming a kind of "belts" of hydrophobicity. When a channel resides in a closed/inactivated state, this prevents spontaneous diffusion of water and ions through the membrane. At the same time, when a channel is activated and, consequently, the pore radius increases, especially in the narrowest places (the so-called " activation gates"), effective transport of water molecules and ions across the membrane is observed. Such effect is known as “hydrophobic gating”, and it can block water and ion transport without full occlusion of the pore (typically with a radius of Cα atoms ≤ 4 Å) [1]. Apparently, the transport through the hydrophobic gates may by facilitated by some polar "helper groups" of amino acid residues that assist polar/charged substances (like water and ions) to overcome the energy barrier created by non-polar environment.

Keywords: Ионные каналы, TRPV1, ion channels, Ионная проводимость, ionic conductivity, hydrophobic gate, TRPV1, гидрофобный затвор