Translational regulation of the N-methyl-D-aspartate receptor subunit NR1.

Formation of functional N-methyl-D-aspartate (NMDA) receptor channels requires the essential NMDA receptor subunit NR1 and one or more of the modulatory subunits NR2A-D and in some cases an additional subunit NR3A or NR3B. Recent studies indicate that NR1 expression is regulated at translation under both physiological and pathological conditions. The rat pheochromocytoma cell line (PC12) has been used as a model system for NR1 gene expression studies. Characterization of the posttranscriptional regulatory mechanisms suggested the posttranslational degradation and translational regulation of NR1 protein in PC12 cells. In addition a recent study on the translational regulation of NR1 mRNA in intact brain identified two translationally distinct pools of NR1 mRNA. In this review we summarize the evidence for translational regulation of NR1 expression in PC12 cells and the brain.