Glutamate receptor ionotropic, NMDA 1 (GRIN1) (GRIN1)

The Glutamate receptor ionotropic, NMDA 1 (GRIN1) subunit contains the essential glycine-binding site of the N-methyl-D-aspartate (NMDA) receptor complex (UniProt P35486). This site is distinct from the glutamate-binding site found on NR2 subunits and must be occupied by glycine or D-serine for the receptor to function (StatPearls, NMDA Receptor). As an obligatory co-agonist site, it plays a pivotal role in mediating excitatory neurotransmission, synaptic plasticity, and the mechanisms underlying learning and memory (PubMed, PMID: 25393014). Dysregulation of NMDA receptor activity via this site is implicated in various neurological and psychiatric conditions, including schizophrenia, where hypofunction is a leading hypothesis, and neurodegenerative diseases like Alzheimer's (NIH, Gene ID: 2902). Pharmacological modulation of the glycine site, using agonists like D-cycloserine or antagonists like gavestinel, provides a therapeutic window to adjust NMDA receptor signaling with potentially fewer side effects than direct channel blockers (PubChem, CID 3486).

Other names

NMDA receptor subunit 1NR1GluN1N-methyl-D-aspartate receptor subunit NR1Strychnine-insensitive glycine binding siteNMDA receptor glycine site

Binding of glycine or D-serine to the NR1 subunit acts as an obligatory co-agonist, facilitating the opening of the NMDA receptor's cation-conducting pore when glutamate also binds to the NR2 subunit and the magnesium block is removed by depolarization.