Expression of endogenous NMDAR1 transcripts without receptor protein suggests post-transcriptional control in PC12 cells.
Expression of RNA for the NMDAR1 subunit of the N-methyl-D-aspartate receptor was detected by Northern hybridization in both nerve growth factor-differentiated and undifferentiated rat pheochromocytoma (PC12) cells. The NMDA receptor type 1 (NMDAR1) message in PC12 cells was similar in size to that expressed in hippocampal neurons. PC12 cell cDNAs that were amplified by polymerase chain reaction with primers flanking the coding region of NMDAR1 corresponded to the NMDAR1 splice variant NMDA receptor type 1 isoform C (NMDAR1C). Using calcium imaging or patch-clamp recording, no functional NMDA-gated ion channels were found in PC12 cells. A monoclonal antibody against NMDAR1 was developed in order to investigate whether or not NMDAR1 protein was present in PC12 cells. Only trace amounts of NMDAR1 protein were found in native PC12 cells. However, expression of NMDAR1 protein was detected in PC12 cells that were transfected with an expression vector containing an NMDAR1C clone under control of a cytomegalovirus promoter. These findings suggest that the expression of NMDAR1 protein in PC12 cells may be controlled by post-transcriptional mechanisms. The PC12 cell line may serve as a model system for the study of the transcriptional, post-transcriptional, and translational regulation of NMDAR1. Furthermore, the presence of NMDAR1 RNA in a particular cell type may not necessarily indicate expression of NMDAR1 protein.
Sucher
N J
NJ
Laboratory of Cellular and Molecular Neuroscience, Department of Neurology, Children's Hospital, Boston, Massachusetts 02115
Brose
N
N
Molecular Neurobiology Laboratory, the Salk Institute, La Jolla, California 92037
Deitcher
D L
DL
Department of Genetics, Boston, Massachusetts 02115
Awobuluyi
M
M
Laboratory of Cellular and Molecular Neuroscience, Department of Neurology, Children's Hospital, Boston, Massachusetts 02115|Program in Neuroscience, Boston, Massachusetts 02115
Gasic
G P
GP
Molecular Neurobiology Laboratory, the Salk Institute, La Jolla, California 92037
Bading
H
H
Department of Microbiology and Molecular Genetics, Boston, Massachusetts 02115
Cepko
C L
CL
Department of Genetics, Boston, Massachusetts 02115|Program in Neuroscience, Boston, Massachusetts 02115
Greenberg
M E
ME
Department of Microbiology and Molecular Genetics, Boston, Massachusetts 02115|Howard Hughes Medical Institute, Boyer Center for Molecular Medicine, Yale University School of Medicine, New Haven, Connecticut 06510|Departments of Neurology, Beth Israel Hospital, Brigham and Women's Hospital, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts 02115
Jahn
R
R
Departments of Neurology, Beth Israel Hospital, Brigham and Women's Hospital, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts 02115
Heinemann
S F
SF
Molecular Neurobiology Laboratory, the Salk Institute, La Jolla, California 92037
Lipton
S A
SA
Laboratory of Cellular and Molecular Neuroscience, Department of Neurology, Children's Hospital, Boston, Massachusetts 02115|Program in Neuroscience, Boston, Massachusetts 02115|Departments of Neurology, Beth Israel Hospital, Brigham and Women's Hospital, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts 02115
D017398:Alternative Splicing; D000818:Animals; D001253:Astrocytes / Q000378:metabolism; D001483:Base Sequence; D002454:Cell Differentiation / Q000187:drug effects; D002460:Cell Line; D002478:Cells, Cultured; D017931:DNA Primers; D004246:Dimethylphenylpiperazinium Iodide / Q000494:pharmacology; D015870:Gene Expression; D015972:Gene Expression Regulation, Neoplastic; D014644:Genetic Variation; D006624:Hippocampus / Q000378:metabolism; D006801:Humans; D007668:Kidney; D046911:Macromolecular Substances; D008564:Membrane Potentials / Q000187:drug effects; D008969:Molecular Sequence Data; D008970:Molecular Weight; D016202:N-Methylaspartate / Q000494:pharmacology; D009414:Nerve Growth Factors / Q000494:pharmacology; D016716:PC12 Cells; D016133:Polymerase Chain Reaction; D012333:RNA, Messenger / Q000302:isolation & purification / Q000378:metabolism; D016194:Receptors, N-Methyl-D-Aspartate / Q000096:biosynthesis* / Q000235:genetics*; D013570:Synaptic Membranes / Q000378:metabolism; D014158:Transcription, Genetic; D014162:Transfection
D017931:DNA Primers; D046911:Macromolecular Substances; D009414:Nerve Growth Factors; D012333:RNA, Messenger; D016194:Receptors, N-Methyl-D-Aspartate; D004246:Dimethylphenylpiperazinium Iodide; D016202:N-Methylaspartate