Growth factor-dependent trafficking of cerebellar NMDA receptors via protein kinase B/Akt phosphorylation of NR2C.
NMDA receptor subunit composition varies throughout the brain, providing molecular diversity in NMDA receptor function. The NR2 subunits (NR2A-D) in large part dictate the distinct functional properties of NMDA receptors and differentially regulate receptor trafficking. Although the NR2C subunit is highly enriched in cerebellar granule cells and plays a unique role in cerebellar function, little is known about NR2C-specific regulation of NMDA receptors. Here, we demonstrate that PKB/Akt directly phosphorylates NR2C on serine 1096 (S1096). In addition, we identify 14-3-3epsilon as an NR2C interactor, whose binding is dependent on S1096 phosphorylation. Both growth factor stimulation and NMDA receptor activity lead to a robust increase in both phosphorylation of NR2C on S1096 and surface expression of cerebellar NMDA receptors. Finally, we find that NR2C expression, unlike NR2A and NR2B, supports neuronal survival. Thus, our data provide a direct mechanistic link between growth factor stimulation and regulation of cerebellar NMDA receptors.
Chen
Bo-Shiun
BS
National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892, USA. chenbos@ninds.nih.gov
Roche
Katherine W
KW
D048948:14-3-3 Proteins / Q000378:metabolism; D000409:Alanine / Q000235:genetics; D000818:Animals; D019921:Biotinylation / Q000379:methods; D002461:Cell Line, Transformed; D002478:Cells, Cultured; D002531:Cerebellum / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D003712:Dendrites / Q000187:drug effects / Q000502:physiology; D018691:Excitatory Amino Acid Antagonists / Q000494:pharmacology; D015870:Gene Expression / Q000187:drug effects / Q000235:genetics; D049452:Green Fluorescent Proteins / Q000235:genetics; D006624:Hippocampus / Q000187:drug effects / Q000378:metabolism; D006801:Humans; D047468:Immunoprecipitation / Q000379:methods; D066298:In Vitro Techniques; D007334:Insulin-Like Growth Factor I / Q000494:pharmacology*; D008164:Luminescent Proteins / Q000378:metabolism; D051379:Mice; D009154:Mutation / Q000235:genetics; D016202:N-Methylaspartate / Q000494:pharmacology; D009474:Neurons / Q000166:cytology / Q000187:drug effects / Q000502:physiology; D051058:Oncogene Protein v-akt / Q000378:metabolism*; D010766:Phosphorylation / Q000187:drug effects; D017434:Protein Structure, Tertiary / Q000235:genetics; D021381:Protein Transport / Q000187:drug effects / Q000502:physiology; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism*; D051381:Rats; D016194:Receptors, N-Methyl-D-Aspartate / Q000235:genetics / Q000378:metabolism*; D012694:Serine / Q000235:genetics / Q000378:metabolism; D015398:Signal Transduction / Q000187:drug effects / Q000502:physiology; D014162:Transfection / Q000379:methods; D014633:Valine / Q000031:analogs & derivatives / Q000494:pharmacology
D048948:14-3-3 Proteins; D018691:Excitatory Amino Acid Antagonists; D008164:Luminescent Proteins; C120997:NR2A NMDA receptor; C432823:NR2C NMDA receptor; D016194:Receptors, N-Methyl-D-Aspartate; C413663:fluorescent protein 583; D049452:Green Fluorescent Proteins; D012694:Serine; D016202:N-Methylaspartate; D007334:Insulin-Like Growth Factor I; C056639:2-amino-5-phosphopentanoic acid; D051058:Oncogene Protein v-akt; D051057:Proto-Oncogene Proteins c-akt; D014633:Valine; D000409:Alanine