展開されたタンパク質反応:ストレス経路からホメオスタティック調節まで
1Howard Hughes Medical Institute and Department of Biochemistry and Biophysics, University of California, San Francisco, CA 94158, USA. peter@walterlab.ucsf.edu
Science (New York, N.Y.)
|November 26, 2011
まとめ
細胞は,展開タンパク質応答 (UPR) を通して,エンドプラズマ網膜 (ER) のタンパク質の折り畳みを制御する. このストレス反応経路は,ERホメオスタシスを維持するか,展開されたタンパク質が蓄積されたときに細胞死を引き起こす.
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:
- 分泌または細胞表面に表示されるためのタンパク質は,エンドプラズマ網膜 (ER) の内部に正しく折りたたまれなければなりません.
- 適切なタンパク質の折り畳みは,細胞の機能と生存に不可欠です.
- ERには,タンパク質の折りたたみ精度を保証するメカニズムがあります.
研究 の 目的:
- ERで展開されたタンパク質に対する細胞の反応を要約します.
- ERホメオスタシスの維持における展開タンパク質応答 (UPR) の役割を明らかにする.
- UPRメカニズムと疾患の関連性に関する理解における最近の進歩を強調する.
主な方法:
- 概要では,方法が明記されていないが,細胞経路と遺伝子調節について論じている.
- 細胞内信号伝達経路に焦点を当てています.
- 遺伝子発現の調節について説明します.
主要な成果:
- ERは,未折たタンパク質 (ERストレス) でオーバーロードされたときに,未折たタンパク質応答 (UPR) を活性化します.
- UPRは,少なくとも3つの異なるシグナルブランチで構成されています.
- これらのUPR分岐は,ERバランスを維持するために遺伝子を調節するか,ストレスが持続した場合にアポトーシスを誘導します.
結論:
- UPRは,ERのストレスに対する重要な細胞防衛機構です.
- UPRの調節不良は,様々な疾患に起因しています.
- 最近の研究では,UPRシグナル伝達とその病理学的役割の新たな複雑性が明らかになりました.
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