タイロシンキナーゼの負の調節体c-Cblは,RING型,E2依存のユビキチンタンパク質リガゼとして作用する
C A Joazeiro1, S S Wing, H Huang
1The Salk Institute, Molecular Biology and Virology Laboratory, La Jolla, CA 92037, USA.
Science (New York, N.Y.)
|October 9, 1999
まとめ
c-Cblタンパク質は,ユビキチン-タンパク質リガゼとして作用し,受容体タンパク質-チロシンキナーゼ (RPTKs) を対象に分解する. この発見は,細胞の信号伝達経路を制御するための新しいメカニズムを明らかにしています.
科学分野:
- セルラー・シグナリング
- タンパク質のユビキチン化
- 分子生物学は分子生物学である.
背景:
- 受容体タンパク質チロシンキナーゼ (RPTKs) の信号終結は,ユビキチン化と分解を伴う.
- c-Cblアダプタータンパク質は,そのSH2およびRINGドメインを通じてRPTKのユビキチネーションに影響を与えます.
研究 の 目的:
- RPTKの信号終止におけるc-Cblの役割を明らかにする.
- ubiquitin-protein ligaseとしてc-Cblがどのように機能するかを決定する.
主な方法:
- c-Cbl,RPTKs,およびユビキチン結合酵素の相互作用を調査する.
- ユビキチネーションプロセスにおけるc-Cbl (SH2とRING) の機能領域を分析する.
主要な成果:
- c-Cblは,ユビキチンタンパク質リガゼ (E3) として機能する.
- c-CblのSH2ドメインは,活性化された血小板由来成長因子受容体のようなチロシン・リン酸化基板を認識する.
- c-CblのRINGドメインは,E2ユビキチン結合酵素を募集し,活性化する.
結論:
- c-Cblは,ユビキチン系における基板標的化のための明確なメカニズムを提供します.
- この発見は,ユビキチネーションがRPTKシグナル伝達をどのように調節するかの理解を広げています.
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