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ERのストレスは,BH3のみのタンパク質Bimを活性化することで,アポトーシスを引き起こす
Hamsa Puthalakath1, Lorraine A O'Reilly, Priscilla Gunn
1The Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia.
Cell
|July 3, 2007
まとめ
エンドプラズマ網膜 (ER) のストレスは,Bimタンパク質を活性化することによって細胞死を誘発する. デフォスフォリレーションとトランスクリプション誘導を含む新しい経路は,ERのストレス誘発のアポトーシスメカニズムを明らかにします.
科学分野:
- 細胞生物学 細胞生物学
- 分子生物学は分子生物学である.
- バイオケミストリー バイオケミストリー
背景:
- エンドプラズマ網膜 (ER) のストレスは,誤った折りたたまれたタンパク質や薬によって引き起こされ,細胞死につながる可能性があります.
- ERストレスとアポトーシスを関連付ける正確なメカニズムは,特に退行性疾患では,完全に理解されていません.
- Bimはプロアポプトティックなタンパク質で,ストレスによる細胞死において重要な役割を果たし,様々なメカニズムによって調節されます.
研究 の 目的:
- ERストレスがアポトーシスを誘発する分子メカニズムを解明する.
- ERにおけるBimの役割と調節を調査する. ストレス誘発細胞死.
- ERのストレス関連疾患の潜在的治療標的を特定する.
主な方法:
- ERストレス誘発アポトーシスを研究するために,細胞培養と全動物モデルを使用しました.
- ERのストレス条件下でのBimタンパク質のレベルと活動の調節を調査しました.
- Bim活性化におけるタンパク質フォスファタゼ2A (PP2A) とCHOP-C/EBPalphaの関与を分析した.
主要な成果:
- Bimは,ERのストレス誘発性アポトーシスにおいて,様々な細胞タイプおよびin vivoにおいて不可欠である.
- ERのストレスは,2つの新しい経路を通じてBimを活性化させる:PP2A媒介による脱酸化 (分解を阻害する) とCHOP-C/EBPalpha媒介の転写誘導.
- PP2Aによる脱酸化はBimのユビキチン化とプロテアソマル分解を防止し,CHOP-C/EBPalphaはBimの転写を直接増加させる.
結論:
- この研究は,ERのストレスがBim.経由でアポトーシスを引き起こす分子経路を定義しています.
- これらの発見は,PP2AとCHOP-C/EBPalphaが,ERストレスにおけるBimの主要な調節体であることを明らかにしています.
- 特定されたメカニズムは,ERストレスに関連した疾患に対する潜在的な治療目標を提供します.
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