ミトコンドリア経由のカスパース-3活性化は,長期的なうつ病およびAMPA受容体の内部化のために必要である
Zheng Li1, Jihoon Jo, Jie-Min Jia
1The Picower Institute for Learning and Memory, Massachusetts Institute of Technology, Cambridge, MA 02139, USA. lizheng2@mail.nih.gov
Cell
|June 1, 2010
まとめ
ミトコンドリアのカスパース-3の活性化は,長期うつ病 (LTD) とニューロン内のAMPA受容体除去に不可欠です. このアポトーシス経路は,細胞死を引き起こすことなく,シナプス性可塑性にとって不可欠です.
科学分野:
- 神経科学は神経科学である.
- 分子生物学は分子生物学である.
- 細胞生物学 細胞生物学
背景:
- 長期うつ病 (LTD) を含むシナプス可塑性は,脳の機能にとって不可欠です.
- LTDはAMPA受容体の除去を伴うが,その分子ドライバは完全に理解されていない.
研究 の 目的:
- LTD.中のAMPA受容体の内部化に伴う分子メカニズムを調査する.
- シナプス性可塑性におけるアポトーシス関連タンパク質の役割を決定する.
主な方法:
- カスパーゼ3と9のペプチド阻害剤を使用した.
- カスパース-3ノックアウトマウスを生成し,研究した.
- 過剰発現した抗アポプトシスタンパク質 (XIAP,Bcl-xL) と変異したAkt1タンパク質.
- ヒポキャンパスのニューロンとスライスにおけるNMDA受容体の刺激を調べた.
主要な成果:
- ミトコンドリアによって開始されるカスパース-3の活性化は,LTDとAMPA受容体の内部化に必須です.
- カスパース3または -9を阻害すると,LTDと受容体除去が阻害されます.
- LTDはカスパゼ-3ノックアウトマウスで廃止され,LTPは影響を受けなかった.
- XIAP,Bcl-xL,またはカスパースに抵抗するAkt1の過剰発現は,LTD.Ltd.を予防しました.
- NMDA受容体刺激は,アポトーシスを誘導することなく,デンドライトのカスパース-3を活性化します.
結論:
- ミトコンドリアのカスパース-3活性化は,LTD.を駆動する重要な分子メカニズムです.
- アポプトシス経路の分子機構は,突如,シナプス性可塑性に関与している.
- カスパース3は,LTD.期間中のAMPA受容体密輸を規制する上で重要な役割を果たします.
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