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展開されたタンパク質応答を制御する転写因子の活動を調節する新しいメカニズム
1Department of Biochemistry and Biophysics, University of California, School of Medicine, San Francisco 94143-0448, USA.
Cell
|November 1, 1996
まとめ
細胞は,Hac1pレベルを制御することによって,展開されたタンパク質応答 (UPR) を活性化します. 調節されたmRNAスプライシングは,重要な転写因子であるHac1pを安定させ,UPR遺伝子の活性化を可能にします.
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.
- 遺伝学 遺伝学とは
背景:
- 細胞は,展開されたタンパク質によって引き起こされるエンドプラズマ網膜 (ER) のストレスを管理するメカニズムを持っています.
- 展開タンパク質応答 (UPR) は,ERストレス情報を核に伝達する重要な細胞内信号経路です.
研究 の 目的:
- UPRの主要な規制当局を特定する.
- 転写因子Hac1p.を制御する規制メカニズムを解明する.
主な方法:
- UPRに関与する転写因子の特定.
- Hac1p発現と調節の分析.
- mRNAのスプライシングとタンパク質の分解経路の研究.
主要な成果:
- 基本的なルシンのジッパー転写因子であるHac1pは,UPRにとって不可欠です.
- Hac1pは,UPR調節遺伝子プロモーターのUPR要素と結合する.
- Hac1pは,UPR活性化された細胞にのみ存在し,そのレベルは制御されたmRNAスプライシングによって制御されます.
- スプライシングはHac1pを修正し,迅速なユビキチン依存性分解に対する耐性を高めます.
結論:
- Hac1p発現の複雑な調節は,UPRのための複数の制御ポイントを提供します.
- Hac1p mRNAの調節されたスプライシングは,UPRの活性化における重要なステップです.
- スプライシングによるHac1pの安定化は,UPR経路におけるその機能の鍵です.
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