カスパス3と7:アポトーシスのミトコンドリアイベントの主要な媒介者
Saquib A Lakhani1, Ali Masud, Keisuke Kuida
1Section of Immunobiology, Yale University School of Medicine, New Haven, CT 06520, USA.
Science (New York, N.Y.)
|February 14, 2006
まとめ
カスパス3と7は,プログラム細胞死 (アポトーシス) に不可欠です. これらのエフェクターカスパスを欠いたマウスは,重度の心不全とアポトーシスに対する抵抗を示し,細胞生存における彼らの重要な役割を強調した.
科学分野:
- 細胞生物学 細胞生物学
- バイオケミストリー バイオケミストリー
- 遺伝学 遺伝学とは
背景:
- アポトーシスは,上流信号が下流エフェクターカスパスを活性化することを含む,厳格に規制されたプロセスです.
- カスパース3とカスパース7は,アポプトシス経路における重要な処刑酵素である.
研究 の 目的:
- アポトーシスにおけるエフェクターカスペス3と7のインビボおよびインビトロの役割を調査する.
- 心臓発育とミトコンドリアのアポプトシスイベントに対するカスパス3と7の必要性を決定する.
主な方法:
- カスパース3とカスパース7の両方が欠乏するマウスの世代.
- ノックアウトマウスにおける心臓発達の分析.
- カスパース欠乏性線維芽細胞におけるアポトーシス抵抗性とミトコンドリア機能の評価.
主要な成果:
- カスパゼ3と7欠乏したマウスは,重度の心不全で胚の死亡率を示した.
- 両方のカスパスを欠いた線維芽細胞は,様々な刺激によって誘発されたアポトーシスに抵抗していた.
- ミトコンドリア膜の潜在力は保たれ,アポトーシス誘発因子 (AIF) の核転位はこれらの細胞で低下した.
- バックスの転位とシトクロームcの放出を含む早期のアポプトティックイベントは遅れた.
結論:
- カスパス3と7は,ミトコンドリアと死亡受容体媒介によるアポトーシスの重要な媒介である.
- これらのエフェクターカスパスは,アポトーシス中の重要なミトコンドリアイベントを開始する上で重要な役割を果たします.
- カスパゼ3と7の欠如は発達障害につながり,その生理学的重要性を強調する.
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