SH2とSH3ドメイン: 細胞質シグナル伝達タンパク質の相互作用を制御する要素
C A Koch1, D Anderson, M F Moran
1Division of Molecular and Developmental Biology, Samuel Lunenfeld Research Institute, Mount Sinai Hospital, Toronto, Ontario, Canada.
Science (New York, N.Y.)
|May 3, 1991
まとめ
Srcホモロジー (SH) ドメイン2と3は,チロシンキナーゼを標的タンパク質に結合することによって,細胞シグナル伝達に不可欠です. これらの非触媒ドメインは,タンパク質複合体の形成を媒介し,成長因子に対する細胞内反応を制御します.
科学分野:
- セルラー・シグナリング
- 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:
- Srcホモロジー (SH) 領域2と3は,細胞質シグナル伝達タンパク質の保存された非触媒ドメインである.
- これらのドメインは受容体タンパク質-チロシンキナーゼによって調節され,フォスフォリファーゼC-ガンマとRas GTPase活性化などの経路に関与しています.
- SH2ドメインは,正常なシグナル伝達と細胞変容に不可欠なチロシンリン酸化ポリペプチドに結合します.
研究 の 目的:
- タンパク質-チロシンキナーゼシグナル伝達経路におけるSH2およびSH3ドメインの役割を明らかにする.
- これらのドメインがタンパク質複合体の形成を媒介し,細胞内反応を制御する方法を理解する.
- SH2およびSH3ドメインを含む非触媒タンパク質の機能をアダプタとして探求する.
主な方法:
- 細胞質シグナル伝達タンパク質における保存されたタンパク質ドメイン (SH2およびSH3) の分析.
- SH2ドメイン結合のスイッチとしてのチロシンリン酸化の研究.
- プラズマ膜におけるヘテロメアタンパク質複合体の形成の検査.
主要な成果:
- SH2ドメインはチロシンリン酸化ポリペプチドに結合し,ヘテロメア複合体の形成を媒介する.
- SH3ドメインは,SH2と共に,細胞骨格と膜との相互作用を調節する.
- SH2およびSH3ドメインを持つ非触媒性タンパク質は,アダプタとして作用し,チロシンキナーゼを標的タンパク質に結合させます.
結論:
- SH2とSH3ドメインは,成長因子刺激に対する細胞内反応の重要な調節体である.
- SH2ドメインによって介されるタンパク質複合体の形成は,信号伝達経路を制御する.
- 非触媒的アダプタータンパク質は,チロシンキナーゼによる信号伝達において重要な役割を果たします.
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