Project/Area Number |
13480270
|
Research Category |
Grant-in-Aid for Scientific Research (B)
|
Allocation Type | Single-year Grants |
Section | 一般 |
Research Field |
Neuroscience in general
|
Research Institution | Okazaki National Research Institutes |
Principal Investigator |
IKENAKA Kazuhiro Okazaki National Research Institutes, National Institute for Physiological Sciences, Department of Molecular Physiology, Professor, 生理学研究所, 教授 (00144527)
|
Co-Investigator(Kenkyū-buntansha) |
NAKAHIRA Kensuke Saitama Medical School, Department of Physiology, Lecturer, 医学部, 講師 (10260043)
BABA Hiroko Tokyo University of Pharmacy and Life Science, Department of Molecular Neurobiology, Professor=, 薬学部, 教授 (40271499)
ONO Katsuhiko Okazaki National Research Institutes, National Institute for Physiological Sciences, Department of Molecular Physiology, Associate Professor, 生理学研究所, 助教授 (30152523)
藤本 一朗 岡崎国立共同研究機構, 統合バイオサイエンスセンター, 助手 (70264710)
|
Project Period (FY) |
2001 – 2003
|
Project Status |
Completed (Fiscal Year 2003)
|
Budget Amount *help |
¥15,000,000 (Direct Cost: ¥15,000,000)
Fiscal Year 2003: ¥4,400,000 (Direct Cost: ¥4,400,000)
Fiscal Year 2002: ¥4,400,000 (Direct Cost: ¥4,400,000)
Fiscal Year 2001: ¥6,200,000 (Direct Cost: ¥6,200,000)
|
Keywords | Voltage-gated K channel / Voltage-gated Na channel / Synapse formation / node of Ranvier / paranodal junction / myelination / cerebellar granule neuron / paranodal junction / Ca<2+>センサータンパク / GFP |
Research Abstract |
Compartmentalization of neuronal function is achieved by highly localized clustering of ion channels in discrete subcellular membrane domains. Voltage-gated potassium (Ky) and sodium (Nay) channels exhibit highly variable cellular and subcellular patterns of expression. To understand how they are regulated, we focused on the two distinct subcellular domains: localization at synapses/dendrites and nodes of Ranvier. Kv4.2, a voltage-gated K channel, shows somatodendritic localization in cerebellar granule cells. We found that its subcellular localization changes from soma to the dendrites and synapses during synaptogenesis, and the neuronal activity plays a key role in this change. This induction of localization was mediated by either NMDA or AMPA receptors. Nav and Kv in myelinated axons show striking segregation at nodes of Ranvier. The axoglial paranodal junction is essential for the proper localization of these ion channels. We showed that sulfatide, a myeline glycolipid, and CD9,a member of the tetraspanin family, play an important role on the regulation of ion-channel localization through the formation of paranodal junction.
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