チャペロニン補助折り畳みの経路に沿ったタンパク質構成のモニタリング
Shruti Sharma1, Kausik Chakraborty, Barbara K Müller
1Department of Cellular Biochemistry, Max Planck Institute of Biochemistry, Am Klopferspitz 18, D-82152 Martinsried, Germany.
Cell
|April 9, 2008
まとめ
バクテリアのGroEL/GroESチャペロンシステムと上流のDnaK/DnaJ (Hsp70) は,タンパク質の折り畳みを支援する. この研究では,GroEL/GroESがどのように展開され,その後の形状の変化によってタンパク質を再折り曲げ,誤った折り曲げを防止するかを明らかにしています.
科学分野:
- 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
- タンパク質の折りたたみ
背景:
- GroEL/GroESのチャペロニン系は,細菌のタンパク質折り畳みに極めて重要です.
- 新しく合成されたタンパク質は,GroELに到達する前に,DnaK/DnaJ (Hsp70) のような上流チャペロンと相互作用します.
研究 の 目的:
- シングル分子およびアンサンブルFRETを使用して,DnaK/DnaJに沿ってGroEL/GroESのチャペロン経路に沿ったモデル基板の構成的移行をモニタリングする.
- GroEL/GroESがタンパク質の折り畳みを促進するメカニズムを解明する.
主な方法:
- 単一分子フォースター共振エネルギー転送 (smFRET)
- アンサンブル FRETETのアンサンブル
- モデル基板タンパク質の構成変化のモニタリング
主要な成果:
- DnaK/DnaJ (Hsp70) は,ゆっくりと折り畳み,崩壊したタンパク質状態を安定させます.
- GroELは展開と局所的な膨張を誘導し,その後はATP依存の動員と適度な水害性のセグメントの部分的な圧縮が続きます.
- GroESの封装は,完全な圧縮と急速な折りたたみをもたらし,特に水害性の高い地域には特に効果的です.
結論:
- GroEL/GroESシステムは,セグメンタルチェーンの解放と圧縮を活用して,タンパク質を積極的に展開し,再折りたたむ.
- このメカニズムは,特に自発的な水性崩壊によって効率的に折りたたまれないタンパク質の場合,誤った折り畳みを防止します.
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