セパラーゼ誘発のアポトーシスはミトーシスの最小の長さを強制する
Susanne Hellmuth1, Olaf Stemmann2
1Chair of Genetics, University of Bayreuth, Bayreuth, Germany.
Nature
|April 24, 2020
まとめ
セパラーゼは,抗アポプトシスタンパク質MCL1とBCL- XLを直接分裂させ,ミトーシス中の細胞死を引き起こします. このメカニズムは,NEK2Aによって制御され,スピンデルの組み立てチェックポイントの適切な機能を保証し,エラーのあるセルを排除します.
科学分野:
- 細胞生物学
- 分子生物学
- 生物化学
背景:
- 長期間のミトーシスはアポトーシスに,短縮されたミトーシスはアヌプロイドに繋がる.
- 縮小したミトーシスのアポプトシス経路の活性化における役割は十分に理解されていません.
- アナフェーズの重要な調節体であるセパラーゼは,カスパースのようなドメインを有しているが,細胞死におけるその役割は不明であった.
研究 の 目的:
- ミトーシス中の細胞死におけるセパラーゼの役割を調査する.
- セパラーゼが抗アポプトシスタンパク質を直接分裂するかどうかを判断する.
- 加速されたミトーシスが細胞死につながるメカニズムを解明する.
主な方法:
- ヒトの細胞培養と 生細胞画像
- タンパク質の分裂を検知するためのウェスタン・ブラッティングと免疫プレシピテーション
- 細胞活性の分析とアポトーシスマーカー
- NEK2Aとセパラーゼの抑制とノックダウン
主要な成果:
- セパラーゼは,ヒト細胞内の抗アポプトシスタンパク質 MCL1 と BCL- XL を直接分裂させます.
- MCL1とBCL-XLの分離は,BAKを放出しミトコンドリアの毛穴を形成することによってアポトーシスを促進する.
- MCL1とBCL-XLを分離するには,NEK2Aのリン酸化が必要です.
- スピンドルアセンブリチェックポイントの廃止による加速したミトーシスは,NEK2A分離酵素の相互作用によって細胞死につながる.
結論:
- セパラーゼはミトーシス中のアポトーシスの直接的なトリガーとして,主要な抗アポトーシスタンパク質を分裂させます.
- NEK2A媒介のリン酸化はセパレーズのプロアポプトシス活性を調節する.
- NEK2A分離酵素軸は,ミトスの欠陥を持つ細胞を排除し,アヌプロイドを防ぐためのチェックポイントとして機能する.
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