Ubiquitylation of voltage-gated sodium channels

Handb Exp Pharmacol. 2014:221:231-50. doi: 10.1007/978-3-642-41588-3_11.

Abstract

Ion channel proteins are regulated by different types of posttranslational modifications. The focus of this review is the regulation of voltage-gated sodium channels (Navs) upon their ubiquitylation. The amiloride-sensitive epithelial sodium channel (ENaC) was the first ion channel shown to be regulated upon ubiquitylation. This modification results from the binding of ubiquitin ligase from the Nedd4 family to a protein-protein interaction domain, known as the PY motif, in the ENaC subunits. Many of the Navs have similar PY motifs, which have been demonstrated to be targets of Nedd4-dependent ubiquitylation, tagging them for internalization from the cell surface. The role of Nedd4-dependent regulation of the Nav membrane density in physiology and disease remains poorly understood. Two recent studies have provided evidence that Nedd4-2 is downregulated in dorsal root ganglion (DRG) neurons in both rat and mouse models of nerve injury-induced neuropathic pain. Using two different mouse models, one with a specific knockout of Nedd4-2 in sensory neurons and another where Nedd4-2 was overexpressed with the use of viral vectors, it was demonstrated that the neuropathy-linked neuronal hyperexcitability was the result of Nav1.7 and Nav1.8 overexpression due to Nedd4-2 downregulation. These studies provided the first in vivo evidence of the role of Nedd4-2-dependent regulation of Nav channels in a disease state. This ubiquitylation pathway may be involved in the development of symptoms and diseases linked to Nav-dependent hyperexcitability, such as pain, cardiac arrhythmias, epilepsy, migraine, and myotonias.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Action Potentials
  • Animals
  • Endosomal Sorting Complexes Required for Transport / chemistry
  • Endosomal Sorting Complexes Required for Transport / metabolism*
  • Epithelial Sodium Channels / chemistry
  • Epithelial Sodium Channels / metabolism*
  • Humans
  • Ion Channel Gating*
  • Nedd4 Ubiquitin Protein Ligases
  • Protein Binding
  • Protein Interaction Domains and Motifs
  • Protein Isoforms
  • Signal Transduction
  • Sodium / metabolism*
  • Ubiquitin-Protein Ligases / chemistry
  • Ubiquitin-Protein Ligases / metabolism*
  • Ubiquitination
  • Voltage-Gated Sodium Channels / chemistry
  • Voltage-Gated Sodium Channels / metabolism*

Substances

  • Endosomal Sorting Complexes Required for Transport
  • Epithelial Sodium Channels
  • Protein Isoforms
  • Voltage-Gated Sodium Channels
  • Sodium
  • NEDD4L protein, rat
  • Nedd4 Ubiquitin Protein Ligases
  • Nedd4 protein, human
  • Nedd4 protein, rat
  • Nedd4L protein, human
  • Nedd4l protein, mouse
  • Ubiquitin-Protein Ligases