Glutamate ionotropic receptor NMDA type subunit 2D (GRIN2D) (GRIN2D)

Glutamate ionotropic receptor NMDA type subunit 2D (GRIN2D) is a critical component of the N-methyl-D-aspartate (NMDA) receptor, a ligand-gated ion channel that mediates excitatory neurotransmission in the brain [1, 3]. These receptors are heterotetramers typically composed of two GluN1 and two GluN2 subunits, with the GluN2D subunit providing unique kinetic properties such as slow deactivation and high sensitivity to glutamate [6, 10]. GRIN2D is predominantly expressed during early neurodevelopment and remains in specific adult brain regions, including the thalamus, basal ganglia, and brainstem, where it regulates synaptic plasticity and neuronal excitability [15, 17]. Pathogenic mutations in the GRIN2D gene are a known cause of developmental and epileptic encephalopathy 46 (DEE46), characterized by severe early-onset seizures, intellectual disability, and movement disorders [14, 17]. Gain-of-function variants in this subunit can lead to excessive calcium influx and excitotoxicity, contributing to neuronal damage and the progression of neurological symptoms [2, 12]. Therapeutic interventions often utilize NMDA receptor antagonists like memantine or ketamine to block overactive channels, though these drugs are often non-selective across different NMDA receptor subtypes [2, 12]. Emerging research aims to develop subunit-selective negative allosteric modulators to provide more precise treatment for GRIN-related disorders while minimizing off-target effects [8, 13]. Beyond neurodevelopmental conditions, GRIN2D has also been implicated in the pathophysiology of schizophrenia, Parkinson's disease, and certain types of cancer [1, 3, 17].

Other names

GluN2DNR2DNMDAR2DEB11DEE46EIEE46Glutamate [NMDA] receptor subunit epsilon-4

NMDA receptor antagonist, channel blocker, negative allosteric modulator, and positive allosteric modulator.