Aim:N-methyl-D-aspartate receptors(NMDAR)are heteromeric complexes pri-marily assembled from NR1 and NR2 subunits.In normal conditions,NR2 sub-units assemble into homodimers in the endoplasmic reticulum(ER).Thesehomodimers remain in the ER until they coassemble with NR1 dimers and aretrafficked to the cell surface.However,it still remains unclear whether functionalhomomeric NMDAR exist in physiological or pathological conditions.Methods:We transfected GFP-NR2A alone into HEK293 cells,treated the cells with PKCactivator 12-myristate-13 acetate(PMA),and then detected surface NR2A sub-units with a live cell immunostaining method.We also used a series of NR2Amutants with a partial deletion of its C-terminus to identify the regions that areinvolved in the PMA-mediated surface expression of NR2A subunits.Results:NR2A subunits were expressed on the cell membrane after incubation with PMA(200 nmol/L,30 min),although no functional NMDA channels were detected afterPMA-induced membrane trafficking.Immunostaining with an ER marker alsorevealed that NR2A subunits were exported from the ER after PMA treatment.Furthermore,the deletion of amino acids between 1149-1347 or 1354-1464 ofNR2A inhibited PMA-induced surface expression ofNR2A subunits.Conclusion:First,our data suggests that PMA treatment can induce the surface expression ofhomomeric NR2A subunits.Furthermore,this process is probably mediated bythe NR2A C-terminal region between positions 1149 and 1464. Aim: N-methyl-D-aspartate receptors (NMDAR) are heteromeric complexes pri-marily assembled from NR1 and NR2 subunits.In normal conditions, NR2 sub-units assemble into homodimers in the endoplasmic reticulum (ER). The homomodimers remain in the ER until they coassemble with NR1 dimers and aretrafficked to the cell surface. Even, it still remains unclear whether functionalhomomeric NMDAR exist in physiological or pathological conditions. Methods: We transfected GFP-NR2A alone into HEK293 cells, treated the cells with PKCactivator 12-myristate- 13 acetate (PMA), and then detected surface NR2A sub-units with a live cell immunostaining method. We also used a series of NR2A mutants with a partial deletion of its C-terminus to identify the regions that are in resolved in the PMA-mediated surface expression of NR2A subunits. Results: NR2A subunits were expressed on the cell membrane after incubation with PMA (200 nmol / L, 30 min), although no functional NMDA channels were detected after PMA-induced membrane traffickin Immunostaining with an ER marker alsorevealed that NR2A subunits were exported from the ER after PMA treatment. Still further, the deletion of amino acids between 1149-1347 or 1354-1464 of NR2A inhibited PMA-induced surface expression of NR2A subunits. Conlusion: First, our data suggests that PMA treatment can induce the surface expression of homomeric NR2A subunits. Future and this process is probably mediated by the NR2A C-terminal region between 1149 and 1464.