Symmetry transitions during gating of the TRPV2 ion channel in lipid membranes

Elife. 2019 May 15:8:e45779. doi: 10.7554/eLife.45779.

Abstract

The Transient Receptor Potential Vanilloid 2 (TRPV2) channel is a member of the temperature-sensing thermoTRPV family. Recent advances in cryo-electronmicroscopy (cryo-EM) and X-ray crystallography have provided many important insights into the gating mechanisms of thermoTRPV channels. Interestingly, crystallographic studies of ligand-dependent TRPV2 gating have shown that the TRPV2 channel adopts two-fold symmetric arrangements during the gating cycle. However, it was unclear if crystal packing forces played a role in stabilizing the two-fold symmetric arrangement of the channel. Here, we employ cryo-EM to elucidate the structure of full-length rabbit TRPV2 in complex with the agonist resiniferatoxin (RTx) in nanodiscs and amphipol. We show that RTx induces two-fold symmetric conformations of TRPV2 in both environments. However, the two-fold symmetry is more pronounced in the native-like lipid environment of the nanodiscs. Our data offers insights into a gating pathway in TRPV2 involving symmetry transitions.

Keywords: Ca2+ permeable channel; Oryctolagus cuniculus; TRP channel; cryo-EM; heat sensing ion channel; ligand gated ion channel; molecular biophysics; structural biology.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Animals
  • Cryoelectron Microscopy
  • Diterpenes / metabolism
  • Membranes / enzymology*
  • Protein Binding
  • Protein Conformation
  • Rabbits
  • TRPV Cation Channels / metabolism*
  • TRPV Cation Channels / ultrastructure*

Substances

  • Diterpenes
  • TRPV Cation Channels
  • resiniferatoxin

Associated data

  • PDB/6OO3
  • PDB/6OO4
  • PDB/6OO5
  • PDB/6OO7