STABLE TRANSFECTION OF THE NR1 SUBUNIT IN CHINESE-HAMSTER OVARY CELLSFAILS TO PRODUCE A FUNCTIONAL N-METHYL-D-ASPARTATE RECEPTOR

The NR1 subunit of the N-methyl-D-aspartate (NMDA) receptor cDNA was s tably transfected into Chinese hamster ovary (CHO) cells. Northern ana lysis revealed 3 clonal cell lines expressing high levels of NMDAR1 mR NA (BA1, BA2 and BA3). NMDAR1 protein was readily detected by Western analysis in only one of the clonal populations, BA1. Whole-cell patch clamp analysis revealed a lack of functional NMDA receptors in all of the cell lines, including BA1. NMDA-mediated responses were obtained o nly after a second subunit, NMDAR2A, was transiently expressed in BAI cells. Therefore, the NR1 subunit alone may not be sufficient to form functional NMDA receptors in CHO cells.