Functional significance of input pathway- and cell type-dependent accumulation of non-synaptic NR3A

2019 Fiscal Year Final Research Report

• Project/Area Number: 17K08503
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: General anatomy (including histology/embryology)
• Research Institution: Hokkaido University
• Principal Investigator: Yamasaki Miwako 北海道大学, 医学研究院, 准教授 (10431305)
• Project Period (FY): 2017-04-01 – 2020-03-31
• Keywords: NMDA受容体 / シナプス

Outline of Final Research Achievements

The localization and physiological function of NMDA receptor subunit NR3A remain largely unexplored. In the present study, we found that NR3A was selectively localized to non-synaptic contacts between climbing fiber to cerebellar stellate cells, and those between glutamatergic terminals and somatostatin-positive GABAergic interneurons in the cerebral cortex. At such contacts, NR3A colocalized with NR1 and Kv4.3. To identify molecular partners that constitute biochemical complex, we immunopurified biochemical complex containing NR3A. We found that NR1 but not Kv4.3 was included in the complex. NR3A knockout mouse showed no evident motor discoordination or histological abnormality.

Free Research Field

神経組織学

Academic Significance and Societal Importance of the Research Achievements

脳機能を担う神経回路の発達においてNMDA型グルタミン酸受容体NR3Aは重要な役割を持つが、発現部位やその機能に不明な点が多く解明が期待されている。本研究では、NR3A受容体は他の受容体とは全く異なり、グルタミン酸作動性神経終末の作る非シナプス性結合選択的に、NR1や早期不活性化Kチャネルkv4.3と共に集積することを見出した。このユニークな知見は今後の脳回路研究の発展に貢献することが期待される。