NMDA receptor subtype of glutamate-gated ion channels with high calcium permeability and voltage-dependent sensitivity to magnesium. Mediated by glycine. This protein plays a key role in synaptic plasticity, synaptogenesis, excitotoxicity, memory acquisition and learning. It mediates neuronal functions in glutamate neurotransmission. Is involved in the cell surface targeting of NMDA receptors. Plays a role in associative learning and in long-term memory consolidation. Forms a heteromeric NMDA channel with Nmdar2. Highly expressed in adult heads: in the brain and ring gland. Low expression throughout the entire brain is also seen. Higher expression levels were observed in some scattered cell bodies and part of their fibers, including those from several pairs of DPM (dorsal-posterior-medial) neurons surrounding the calyx, DAL (dorsal-anterior-lateral) and DPL (dorsal-posterior-lateral) neurons in the lateral protocerebrum (LP), VAL (ventral-anterior-lateral) neurons in the anterior protocerebrum, and two pairs of VP (ventral-posterior) neurons in the posterior protocerebrum. Many cell bodies in the optic lobes show preferential expression. Punctuate expression is notably detected in many brain regions including the superior medial protocerebrum. Weakly expressed in the antennal lobes and central complex. Expression first seen in late embryos. Levels are low during larval development and increase in late pupae to persist through to adulthood. Flies exhibit disruption of olfactory learning. Belongs to the glutamate-gated ion channel (TC 1.A.10.1) family.