エンドプラズマ網膜におけるタンパク質の折りたたみにおけるATPと二硫化結合の役割
I Braakman1, J Helenius, A Helenius
1Department of Cell Biology, Yale University School of Medicine, New Haven, Connecticut 06510-8002.
Nature
|March 19, 1992
まとめ
エンドプラズマ網膜 (ER) のタンパク質の折り畳みには代謝エネルギーが必要です. このエネルギーは,正しい折りたたみ,二硫化物結合形成,そして酸化するER環境における誤った折りたたみのタンパク質の救済をサポートします.
科学分野:
- 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
- タンパク質の折りたたみ
背景:
- エンドプラズマ網膜 (ER) の光は細胞外環境を模倣し,タンパク質合成のためのユニークな酸化環境を提供します.
- 他の細胞区画と異なり,ERの酸化性質は,タンパク質の構造と機能に不可欠な二硫化結合の形成を促進します.
研究 の 目的:
- ER内のタンパク質の折り畳みのエネルギー依存性を調査する.
- モデルとしてインフルエンザのヘマグルチニンを用いて,二硫化結合形成とタンパク質成熟における代謝エネルギーの役割を明らかにする.
主な方法:
- 還元剤ディチオトリトールを活体細胞における二硫化物結合形成を抑制するために使用した.
- 阻害されたジスルファイド結合形成と変化する代謝エネルギーレベルの下でのインフルエンザヘマグルーチニンの折り畳みプロセスを研究した.
主要な成果:
- インフルエンザ・ヘマグルチニンの正しい折りたたみと二硫化結合形成はエネルギーに依存するプロセスであることを実証した.
- 代謝エネルギーが,二硫化物結合集積物から,誤った折りたたまれたタンパク質を救うために必要であることを示した.
- ウイルスのグリコプロテインの酸化,折りたたみ,およびオリゴメリゼーションに適した状態を維持するためにエネルギーが不可欠であることを確認しました.
結論:
- エンドプラズマ網膜におけるタンパク質の折り畳みと成熟は,細胞の代謝エネルギーに極めて依存しています.
- 代謝エネルギーは,タンパク質の折り畳みストレス管理と,ER内のタンパク質ホメオスタシスの維持において重要な役割を果たします.
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