Structural basis of subtype-selective competitive antagonism for GluN2C/2D-containing NMDA receptors

Nat Commun. 2020 Jan 22;11(1):423. doi: 10.1038/s41467-020-14321-0.

Abstract

N-Methyl-D-aspartate receptors (NMDARs) play critical roles in the central nervous system. Their heterotetrameric composition generates subtypes with distinct functional properties and spatio-temporal distribution in the brain, raising the possibility for subtype-specific targeting by pharmacological means for treatment of neurological diseases. While specific compounds for GluN2A and GluN2B-containing NMDARs are well established, those that target GluN2C and GluN2D are currently underdeveloped with low potency and uncharacterized binding modes. Here, using electrophysiology and X-ray crystallography, we show that UBP791 ((2S*,3R*)-1-(7-(2-carboxyethyl)phenanthrene-2-carbonyl)piperazine-2,3-dicarboxylic acid) inhibits GluN2C/2D with 40-fold selectivity over GluN2A-containing receptors, and that a methionine and a lysine residue in the ligand binding pocket (GluN2D-Met763/Lys766, GluN2C-Met736/Lys739) are the critical molecular elements for the subtype-specific binding. These findings led to development of UBP1700 ((2S*,3R*)-1-(7-(2-carboxyvinyl)phenanthrene-2-carbonyl)piperazine-2,3-dicarboxylic acid) which shows over 50-fold GluN2C/2D-selectivity over GluN2A with potencies in the low nanomolar range. Our study shows that the L-glutamate binding site can be targeted for GluN2C/2D-specific inhibition.

Publication types

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

MeSH terms

  • Animals
  • Binding Sites
  • Binding, Competitive
  • Glutamic Acid / chemistry
  • Glutamic Acid / metabolism
  • Kinetics
  • Receptors, N-Methyl-D-Aspartate / antagonists & inhibitors*
  • Receptors, N-Methyl-D-Aspartate / chemistry*
  • Receptors, N-Methyl-D-Aspartate / genetics
  • Receptors, N-Methyl-D-Aspartate / metabolism
  • Xenopus laevis

Substances

  • NR2C NMDA receptor
  • NR2D NMDA receptor
  • Receptors, N-Methyl-D-Aspartate
  • Glutamic Acid
  • N-methyl D-aspartate receptor subtype 2A