Regulation of NMDA glutamate receptor functions by the GluN2 subunits

• Published in: Journal of neurochemistry 2020-07, Vol.154 (2), p.121-143
• Main Authors: Vieira, Marta, Yong, Xuan Ling Hilary, Roche, Katherine W., Anggono, Victor
• Format: Article
• Language: English
• Subjects: Animals; Calcium; Calcium influx; Calcium ions; Calcium sequestration; Central nervous system; Dendritic Spines - metabolism; endocytosis; endosomal recycling; exocytosis; Functional plasticity; Glutamic acid receptors; Glutamic acid receptors (ionotropic); Humans; Intracellular; Intracellular signalling; Ion channels; Membrane trafficking; Molecular modelling; N-Methyl-D-aspartic acid receptors; NMDA receptors; Protein Subunits - metabolism; Protein Transport - physiology; Proteins; protein–protein interactions; receptor trafficking; Receptors; Receptors, N-Methyl-D-Aspartate - metabolism; Regulatory proteins; Signal transduction; Synapses; Synaptic plasticity
• ISSN: 0022-3042; 1471-4159
• DOI: 10.1111/jnc.14970

The N‐methyl‐D‐aspartate receptors (NMDARs) are ionotropic glutamate receptors that mediate the flux of calcium (Ca2+) into the post‐synaptic compartment. Ca2+ influx subsequently triggers the activation of various intracellular signalling cascades that underpin multiple forms of synaptic plasticity. Functional NMDARs are assembled as heterotetramers composed of two obligatory GluN1 subunits and two GluN2 or GluN3 subunits. Four different GluN2 subunits (GluN2A‐D) are present throughout the central nervous system; however, they are differentially expressed, both developmentally and spatially, in a cell‐ and synapse‐specific manner. Each GluN2 subunit confers NMDARs with distinct ion channel properties and intracellular trafficking pathways. Regulated membrane trafficking of NMDARs is a dynamic process that ultimately determines the number of NMDARs at synapses, and is controlled by subunit‐specific interactions with various intracellular regulatory proteins. Here we review recent progress made towards understanding the molecular mechanisms that regulate the trafficking of GluN2‐containing NMDARs, focusing on the roles of several key synaptic proteins that interact with NMDARs via their carboxyl termini. The N‐methyl‐D‐aspartate glutamate receptors (NMDARs) mediate calcium‐dependent signalling that underpins multiple forms of synaptic plasticity. Different GluN2 (GluN2A‐D) subunits confer NMDARs with distinct ion channel properties and intracellular trafficking pathways. This review article summarizes the current knowledge of the molecular mechanisms that regulate the trafficking of GluN2‐containing NMDARs, focusing on the roles of several key‐binding partners.