eIF2αは刺激性およびソマトスタチンニューロンによる記憶の統合を制御する
Vijendra Sharma1,2, Rapita Sood3,4, Abdessattar Khlaifia5
1Department of Biochemistry, McGill University, Montréal, Québec, Canada. vijendra.sharma@mcgill.ca.
Nature
|October 8, 2020
まとめ
統合ストレス反応 (ISR) 経路を阻害することで,eIF2αのリン酸化が促進され,長期記憶形成が促進されます. これはヒポカンプスの刺激性ニューロンと 特定の抑制性ニューロンの両方の 分子メカニズムによって起こります
科学分野:
- 神経科学
- 分子生物学
- 認知科学
背景:
- 長期記憶の形成は 分子スイッチと タンパク質合成の調節に依存しています
- 統合ストレス反応 (ISR) は,eIF2αリン酸化 (p-eIF2α) によって調節され,記憶の統合における重要な要因である.
- ISRを阻害すると記憶が強化されますが,特定の神経回路は完全に理解されていません.
研究 の 目的:
- 認知処理を制御する神経回路におけるISRとeIF2αの役割を調査する.
- ISR活動が記憶形成に影響を与える特定のタイプのヒポカンプスニューロンを特定する.
主な方法:
- 分子遺伝学を使って 神経回路を解剖した
- 学習中の海馬の神経細胞における eIF2α リン酸化の変化を調べた.
- 特定のニューロンの集団 (刺激性,ソマトスタチン阻害性,パルバルブミン阻害性) で p- eIF2αを消去した.
主要な成果:
- 学習により,海馬の刺激性およびソマトスタチン発現抑制性ニューロンにおけるeIF2αのリン酸化が低下した.
- これらのニューロンのp-eIF2αを消去すると,mRNA翻訳とシナプス可塑性が増加した.
- これらの特定の神経型において,p-eIF2αの消去後に長期記憶の強化が観察された.
結論:
- hippocampal excitatoryおよび somatostatin発現抑制ニューロンのeIF2α依存mRNA翻訳は,記憶の統合に不可欠である.
- これらの発見は,異なるニューロン集団内の自律的なメカニズムを明らかにし,ISR経由で認知処理をゲートします.
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