SH3ドメインは,シグナル伝達分子の直接的な細胞局所化を誘導する
D Bar-Sagi1, D Rotin, A Batzer
1Cold Spring Harbor Laboratory, New York 11724.
Cell
|July 16, 1993
まとめ
SH3ドメインは,SH2ドメインではなく,フォスフォリファーゼC-ガンマ (PLC-ガンマ) やGRB2のようなシグナル伝達タンパク質を,アクチン細胞骨格や膜ラッフルなどの特定の細胞部位に誘導する.
科学分野:
- 細胞生物学 細胞生物学
- 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
背景:
- 信号伝達経路は,機能のためにタンパク質の局所化に依存しています.
- フォスフォリファーズC-ガンマ (PLC-ガンマ) とGRB2は,重要なシグナル伝達アダプタである.
- タンパク質の局所化におけるSH2およびSH3ドメインの役割は完全に理解されていません.
研究 の 目的:
- PLC-ガンマとGRB2ドメインの細胞分布を調査する.
- サブセルラーターゲティングに責任を負う特定のドメインを決定する.
主な方法:
- PLC-ガンマおよびGRB2タンパク質をラット胚の線維芽細胞に微量注入する.
- タンパク質の局所化を視覚化するための免疫光顕微鏡.
- SH2またはSH3ドメインで機能喪失変異を有するタンパク質の分析.
主要な成果:
- PLC-ガンマ SH2/SH3およびSH3ドメインは,アクチン細胞骨格に局所されています.
- PLC-gamma SH2ドメインは,拡散した細胞質分布を示した.
- GRB2は,SH2ドメインの相互作用から独立して,膜ラッフルに局所化しています.
- SH3変異を持つGRB2は,拡散した細胞質分布を示した.
結論:
- SH3ドメインは,特定のサブセルラー部位にシグナル伝達分子をターゲットにするために重要です.
- SH2ドメインは,アクチン細胞骨格への局所化には不十分である.
- 膜ラッフルへのGRB2の局所化は,そのSH3ドメインによって媒介されます.
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