Nedd4 is a specific E3 ubiquitin ligase for the NMDA receptor subunit GluN2D

Neuropharmacology. 2013 Nov:74:96-107. doi: 10.1016/j.neuropharm.2013.04.035. Epub 2013 Apr 29.


NMDA receptors are a family of glutamate-gated ion channels that regulate various CNS functions such as synaptic plasticity and learning. However hypo- or hyper-activation of NMDA receptors is critically involved in many neurological and psychiatric conditions such as pain, stroke, epilepsy, neurodegeneration, schizophrenia, and depression. Thus, it is important to identify mechanisms (such as by targeted ubiquitination) that regulate the levels of individual subtypes of NMDA receptors. In this study, we used a series of tagged, carboxy terminal constructs of GluN2D to identify associating proteins from rat brain. Of seven different GluN2D C-terminal fragments used as bait, only the construct containing amino acids 983-1097 associated with an E3 ubiquitin ligase, Nedd4. A direct interaction between GluN2D and Nedd4 was confirmed both in vivo and in vitro. This association is mediated by an interaction between GluN2D's C-terminal PPXY motif and the 2nd and 3rd WW domains of Nedd4. Of the four GluN2 subunits, Nedd4 directly interacted with GluN2D and also weakly with GluN2A. Nedd4 coexpression with GluN2D enhances GluN2D ubiquitination and reduces GluN1/GluN2D NMDA receptor responses. These results identify Nedd4 as a novel binding partner for GluN2D and suggest a mechanism for the regulation of NMDA receptors that contain GluN2D subunits through ubiquitination-dependent downregulation. This article is part of the Special Issue entitled 'Glutamate Receptor-Dependent Synaptic Plasticity'.

Keywords: Excitotoxicity; GluN2D subunit; Glutamate; Mass spectrometry; NMDA receptors; Nedd4; Proteomics; Ubiquitin ligase; Ubiquitination.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Down-Regulation
  • Endosomal Sorting Complexes Required for Transport / metabolism*
  • Endosomal Sorting Complexes Required for Transport / physiology
  • HEK293 Cells
  • Humans
  • Membrane Potentials / physiology
  • Mice
  • Nedd4 Ubiquitin Protein Ligases
  • Oocytes / physiology
  • Protein Interaction Domains and Motifs / physiology
  • Protein Subunits / metabolism
  • Protein Subunits / physiology
  • Rats
  • Receptors, N-Methyl-D-Aspartate / metabolism*
  • Receptors, N-Methyl-D-Aspartate / physiology
  • Ubiquitin-Protein Ligases / metabolism*
  • Ubiquitin-Protein Ligases / physiology
  • Ubiquitination
  • Xenopus Proteins
  • Xenopus laevis


  • Endosomal Sorting Complexes Required for Transport
  • NR2D NMDA receptor
  • Protein Subunits
  • Receptors, N-Methyl-D-Aspartate
  • Xenopus Proteins
  • NEDD4L protein, rat
  • Nedd4 Ubiquitin Protein Ligases
  • Nedd4 protein, Xenopus
  • Nedd4 protein, human
  • Nedd4 protein, rat
  • Nedd4l protein, mouse
  • nedd4l protein, Xenopus
  • Ubiquitin-Protein Ligases