タイロシンリン酸化によるフォスフォリファーゼC-ガンマ1の触媒活性増加
S Nishibe1, M I Wahl, S M Hernández-Sotomayor
1Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN 37232-0146.
まとめ
皮質成長因子 (EGF) 受容体によるフォスフォリファーゼC-ガンマ1 (PLC-ガンマ1) のチロシンリン酸化により,その触媒活性が活性化されます. この活性化により,信号伝導が強化され,イノシトール三酸塩とダイアシルグリセロールの生産が増加します.
科学分野:
- バイオケミストリー バイオケミストリー
- 細胞シグナル伝達 細胞信号伝達
- 分子生物学は分子生物学である.
背景:
- フォスフォリファーゼC-ガンマ1 (PLC-ガンマ1) は,ホルモン信号伝達における重要な酵素である.
- Epidermal Growth Factor (EGF) レセプターチロシンキナーゼリン酸化物 PLC-ガンマ 1. エピダーマルの成長因子 (EGF) レセプターチロシンキナーゼリン酸化物 PLC-ガンマ 1.
- EGFの刺激により,フォスファディチルニノシトール4,5-ビスホスファートの水解が起こります.
研究 の 目的:
- タイロシンリン酸化がPLC-ガンマ1の触媒活性を活性化するかどうかを調査する.
- EGF媒介のシグナル伝達におけるチロシンリン酸化の役割を決定する.
主な方法:
- タイロシンリン酸化が,PLC-ガンマ1の触媒活性に及ぼす影響を,無傷の細胞およびインビトロで試験する.
- EGFが活性化するPLC-ガンマ1の活性化を逆転させるため,チロシン特異のフォスファターゼを利用する.
主要な成果:
- チロシンリン酸化により,PLC-ガンマ1の触媒活性が有意に増加した.
- ティロシン特異のフォスファターゼによる脱酸化により,EGFが活性化するPLC-gamma 1の触媒活性が低下した.
結論:
- タイロシンリン酸化は,EGF媒介によるPLC-ガンマ1の触媒活性化のメカニズムである.
- この活性化は,EGFが刺激したイノシトール1,4,5-トリスホスファートおよびダイアシルグリセロールの産生に寄与する.
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