N-Methyl-d-aspartate Receptor Mechanosensitivity Is Governed by C Terminus of NR2B Subunit
| Autor: | Shachee Doshi, David A. Lynch, Tapan P. Patel, Adam J. Hockenberry, Jennifer M. Spaethling, David F. Meaney, Donna M. Geddes-Klein, Pallab Singh |
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| Rok vydání: | 2012 |
| Předmět: |
Protein subunit
PKC Phosphorylation Site Biology Transfection Mechanotransduction Cellular Receptors N-Methyl-D-Aspartate Biochemistry Neurobiology Neurotransmitter receptor Animals Humans Point Mutation Mechanotransduction Receptor Molecular Biology Protein Kinase C Protein kinase C Neurons musculoskeletal neural and ocular physiology HEK 293 cells Cell Biology Molecular biology Rats Cell biology HEK293 Cells nervous system Brain Injuries Mechanosensitive channels psychological phenomena and processes |
| Zdroj: | Journal of Biological Chemistry. 287:4348-4359 |
| ISSN: | 0021-9258 |
| Popis: | N-methyl-D-aspartate receptors (NMDARs), critical mediators of both physiologic and pathologic neurological signaling, have previously been shown to be sensitive to mechanical stretch through the loss of its native Mg(2+) block. However, the regulation of this mechanosensitivity has yet to be further explored. Furthermore, as it has become apparent that NMDAR-mediated signaling is dependent on specific NMDAR subtypes, as governed by the identity of the NR2 subunit, a crucial unanswered question is the role of subunit composition in observed NMDAR mechanosensitivity. Here, we used a recombinant system to assess the mechanosensitivity of specific subtypes and demonstrate that the mechanosensitive property is uniquely governed by the NR2B subunit. NR1/NR2B NMDARs displayed significant stretch sensitivity, whereas NR1/NR2A NMDARs did not respond to stretch. Furthermore, NR2B mechanosensitivity was regulated by PKC activity, because PKC inhibition reduced stretch responses in transfected HEK 293 cells and primary cortical neurons. Finally, using NR2B point mutations, we identified a PKC phosphorylation site, Ser-1323 on NR2B, as a unique critical regulator of stretch sensitivity. These data suggest that the selective mechanosensitivity of NR2B can significantly impact neuronal response to traumatic brain injury and illustrate that the mechanical tone of the neuron can be dynamically regulated by PKC activity. |
| Databáze: | OpenAIRE |
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