メッセンジャーRNAは,エンドプラズマ網膜のストレスシグナルサイトをターゲットにします
Tomás Aragón1, Eelco van Anken, David Pincus
1Department of Biochemistry and Biophysics, University of California at San Francisco, San Francisco, California 94158-2517, USA. Tomas.Aragon@ucsf.edu
Nature
|December 17, 2008
まとめ
エンドプラズマ網膜 (ER) のストレスが展開タンパク質応答 (UPR) を引き起こす. Ire1の活性化により,ER-bound mRNAがクラスタ化され,UPRシグナル伝達とタンパク質折り畳み調節が可能になります.
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,タンパク質の誤折れから生じ,展開タンパク質応答 (UPR) を活性化します.
- UPRは,HAC1 mRNA (酵母) またはXBP1 (メタゾーン) をスプレイスするIre1のようなセンサーによって媒介され,ERホメオスタシスを回復します.
- HAC1 mRNAのイントロンと5' UTRによる翻訳制御は,Hac1の合成を調節する.
研究 の 目的:
- UPR中のIre1活性化とHAC1 mRNAスプライシングの分子メカニズムを調査する.
- Ire1クラスタリングとmRNAリクルートメントが,UPRシグナル伝達にどのように貢献するか解明する.
- HAC1 mRNAターゲティングにおける保存元素の役割を特定する.
主な方法:
- イースト遺伝学と分子生物学技術.
- 顕微鏡を用いたIre1のオリゴメリゼーションと局所化の分析.
- mRNAとタンパク質の相互作用の研究と機能分析.
主要な成果:
- Ire1の活性化により,分離されたER膜焦点にクラスタ化され,高階オリゴーマーが形成されます.
- 未配列のHAC1mRNAは,その3'UTRの2部分の要素を通じて,これらのIre1焦点に採用されます.
- Ire1クラスタリングやmRNAリクルートメントの障害は,UPRシグナリングを著しく損なう.
- HAC1 3' UTR 要素は,他の抑圧されたmRNAを Ire1 焦点に標的にすることができます.
結論:
- Ire1シグナリングセンターへのmRNAの徴募は,真核生物の遺伝子発現を制御するための新しいメカニズムです.
- このプロセスは,効率的なUPR活性化とERストレスへの細胞適応に不可欠です.
- この発見は,ER膜における遺伝子発現調節の新たなパラダイムを示しています.
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