ミトコンドリアのチャペロニンhsp60は,自体の組み立てのために必要です
M Y Cheng1, F U Hartl, A L Horwich
1Howard Hughes Medical Institute, Department of Human Genetics, Yale School of Medicine, New Haven, Connecticut 06510.
Nature
|November 29, 1990
まとめ
ミトコンドリアにおける熱ショックタンパク質60 (hsp60) の組み立てには,既存の複合体が必要です. これは,タンパク質の折りたたみ機構自体が,細胞内の適切な形成のために指導を必要としていることを示唆しています.
科学分野:
- ミトコンドリア生物学 ミトコンドリア生物学
- タンパク質の折りたたみ
- 分子チャペロンは,分子チャペローンである.
背景:
- ヒートショックタンパク質60 (hsp60) は,ミトコンドリア内のタンパク質の折り畳みに不可欠です.
- Hsp60はチャペロニンとして機能し,タンパク質組成に不可欠な14メルの複合体を形成します.
- hsp60複合アセンブリのメカニズムそのものは不明でした.
研究 の 目的:
- 熱ショックタンパク質60 (hsp60) 複合体の組立機構を調査する.
- hsp60サブユニットの自己組み立てが可能か,既存の構造が必要かどうかを判断する.
主な方法:
- hsp60.0に欠陥がある酵母変異体 (mif4) のhsp60アセンブリを研究した.
- 健全な細胞と孤立したミトコンドリアの両方で,野生型のhsp60サブユニットの組み立てを観察しました.
- 輸入されたhsp60サブユニットのインビトロ組立運動を分析した.
主要な成果:
- 新たに輸入されたhsp60サブユニットは,hsp60欠陥の酵母変異体で自己組み立てができませんでした.
- 新しい14-mer複合体の組み立てには,機能する,既存のhsp60複合体が必要です.
- hsp60サブユニットのインビトロ組立は,迅速に (5〜10分間の半減期) 発生し,触媒化されたプロセスを示した.
結論:
- 機能的な熱ショックタンパク質60 (hsp60) 複合体の組み立ては,自発的な自己組み立てプロセスではありません.
- 既存のhsp60構造は,新たに輸入されたサブユニットの組み立てを促進するために必要です.
- これは,タンパク質の構成を in vivo で達成するための主要なメカニズムとして単純な自己組み立てという概念に挑戦しています.
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