IRE1αキナーゼの活性化モードは,異なった細胞運命を決定するために,代替のエンドロビヌクレアゼ出力を制御します
Dan Han1, Alana G Lerner, Lieselotte Vande Walle
1Department of Medicine, University of California, San Francisco, San Francisco, CA 94143-2520, USA.
Cell
|August 12, 2009
まとめ
展開されたタンパク質応答 (UPR) は,エンドプラズマ網膜 (ER) ストレス中に細胞死を引き起こす可能性があります. キナーゼ阻害剤は,IRE1alpha RNaseの活動を変化させ,細胞生存を促進することによって,このアポプトーシスをブロックすることができます.
科学分野:
- 分子生物学は分子生物学である.
- 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
背景:
- エンドプラズマの網膜 (ER) のストレスが展開タンパク質応答 (UPR) を活性化し,ホメオスタシスを回復させます.
- ホメオスタシスが達成されない場合,UPRはアポトーシス,またはプログラム細胞死を引き起こす可能性があります.
- IRE1alphaは,このアポプトシススイッチにおいて重要な役割を果たすERトランスメブランキナーゼ/エンドリボヌクレアゼ (RNase) である.
研究 の 目的:
- ERストレス中にアポトーシスを媒介するIRE1alphaの役割を調査する.
- 細胞生存を促進するためにIRE1alpha活性を調節するメカニズムを探求する.
主な方法:
- IRE1alpha機能を研究するために化学遺伝学を使用しました.
- 実施された in vitro 溶解試験.
- mRNAのスプライシングと崩壊経路を分析した.
主要な成果:
- ERのストレスは,IRE1alphaの自己リン酸化を誘発し,そのRNaseを活性化し,XBP1mRNAをスプレイスし,他のER局所化されたmRNAを劣化させます.
- キナーゼ阻害剤は,IRE1αの自己リン酸化をバイパスし,RNaseを代替モードで活性化します.
- この代替活性化により,XBP1のスプライシングが促進され,mRNAの崩壊が防止され,アポトーシスが回避されます.
結論:
- IRE1alphaの二重キナーゼとRNaseの活動は,ERストレス中の細胞運命を決定するために不可欠です.
- IRE1alpha RNaseの活性をキナーゼ阻害剤で調節すると,細胞生存へのバランスが変化します.
- IRE1alphaのターゲティングは,ERストレスを伴う状態のための潜在的な治療戦略を提供します.
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