TRPC5 channel instability induced by depalmitoylation protects striatal neurons against oxidative stress in Huntington's disease

Biochim Biophys Acta Mol Cell Res. 2020 Feb;1867(2):118620. doi: 10.1016/j.bbamcr.2019.118620. Epub 2019 Dec 6.

Abstract

Protein S-palmitoylation, the covalent lipid modification of the side chain of Cys residues with the 16‑carbon fatty acid palmitate, is the most common acylation, and it enhances the membrane stability of ion channels. This post-translational modification (PTM) determines a functional mechanism of ion channel life cycle from maturation and membrane trafficking to localization. Especially, neurodevelopment is regulated by balancing the level of synaptic protein palmitoylation/depalmitoylation. Recently, we revealed the pathological role of the transient receptor potential canonical type 5 (TRPC5) channel in striatal neuronal loss during Huntington's disease (HD), which is abnormally activated by oxidative stress. Here, we report a mechanism of TRPC5 palmitoylation at a conserved cysteine residue, that is critical for intrinsic channel activity. Furthermore, we identified the therapeutic effect of TRPC5 depalmitoylation by enhancing the TRPC5 membrane instability on HD striatal cells in order to lower TRPC5 toxicity. Collectively, these findings suggest that controlling S-palmitoylation of the TRPC5 channel as a potential risk factor can modulate TRPC5 channel expression and activity, providing new insights into a therapeutic strategy for neurodegenerative diseases.

Keywords: Depalmitoylation; HD; Palmitoylation; TRPC; Trafficking.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Motifs
  • Animals
  • Antineoplastic Agents, Alkylating / toxicity
  • Apoptosis / drug effects
  • Carmustine / toxicity
  • Golgi Apparatus / metabolism
  • HEK293 Cells
  • Humans
  • Huntingtin Protein / genetics
  • Huntington Disease / metabolism
  • Huntington Disease / pathology
  • Lipoylation / drug effects
  • Mice
  • Mice, Transgenic
  • Mutagenesis, Site-Directed
  • Neurons / metabolism*
  • Oxidative Stress* / drug effects
  • Palmitates / pharmacology
  • Protein Stability
  • Protein Subunits / chemistry
  • Protein Subunits / genetics
  • Protein Subunits / metabolism
  • TRPC Cation Channels / chemistry
  • TRPC Cation Channels / genetics
  • TRPC Cation Channels / metabolism*

Substances

  • Antineoplastic Agents, Alkylating
  • HTT protein, human
  • Huntingtin Protein
  • Palmitates
  • Protein Subunits
  • TRPC Cation Channels
  • TRPC5 protein, human
  • 2-bromopalmitate
  • Carmustine