グルココルチコイド受容体の機能は,Hsp90とHsp70のチャペロンサイクルの協調作用によって調節されます
Elaine Kirschke1, Devrishi Goswami2, Daniel Southworth1
1Howard Hughes Medical Institute, University of California, San Francisco, San Francisco, CA 94158, USA; Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, CA 94158, USA.
Cell
|June 21, 2014
まとめ
分子チャペロンであるHsp70とHsp90は,グルココルチコイド受容体 (GR) の機能を調節する. Hsp70はGRを無効化し,コチャペロンを含むHsp90は,その結合結合能力と安定性を回復する.
科学分野:
- 分子チャペロンである分子チャペロン.
- タンパク質の折りたたみと安定性
- セルラー・シグナリング
背景:
- グルココルチコイド受容体 (GR) は,その in vivo 機能のために Hsp90 分子チャペロンを必要とします.
- Hsp90は生体内でリガンド結合に不可欠であるが,浄化されたアポGRは,Hsp90.0なしにリガンドを結合することができる.
- Hsp70は,Hsp90.0へのクライアント配信を容易にすることが知られている.
研究 の 目的:
- GR機能の調節におけるHsp70とHsp90の役割を解明する.
- Hsp70とHsp90が相互作用してGR活動を制御するメカニズムを調査する.
- コチャペロンとATPの水解がGRチャペロン複合体にどのように影響するかを理解するために.
主な方法:
- クリオ電子顕微鏡で,GR:Hsp70:Hsp90:Hop複合体を視覚化しました.
- GRリガンド結合とタンパク質の安定性を評価するための生化学分析.
- ATPの水解とコチャペロンに関する研究 (Hop, p23).
主要な成果:
- Hsp70は部分的に展開してGRを無効化するが,Hsp90はこの無効化を逆転させる.
- GRリガンド結合の完全な回復には,Hsp90 ATPの水解とコチャペロンのホップとp23.
- Hsp90 ATP水解は,Hsp70 ATPサイクルと結合して,クライアント転送を調節する.
- Hsp90からの放出は,GRを集積から保護し,Hsp70.0からの放出とは異なり,リガンド親和性を強化します.
結論:
- Hsp70とHsp90の連携した相互作用は,GRの安定性と機能に不可欠です.
- Hsp90はGRを集積から保護し,そのリガンド結合能力を高めます.
- チャペロンATPサイクルとコチャペロンの相互作用は,GR活動のための規制メカニズムを提供します.
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