キナーゼ媒介のRAS信号は,膜のない細胞質タンパク質粒子を介して伝達される
Asmin Tulpule1, Juan Guan2, Dana S Neel3
1Division of Pediatric Hematology/Oncology, UCSF, San Francisco, CA 94143, USA.
Cell
|April 13, 2021
まとめ
癌細胞は,レセプターチロシンキナーゼ (RTK) とRAS/MAPKのシグナリングを組織するために新しい膜のないタンパク質の粒子を利用します. この発見は,従来の脂質膜から独立した腫瘍性信号伝達の新しい経路を明らかにしています.
科学分野:
- 細胞生物学
- 分子腫瘍学
- 生物化学
背景:
- レセプターチロシンキナーゼ (RTK) 信号は通常,脂質膜で発生する.
- RAS GTPase/MAP キナーゼ (MAPK) 経路の活性化は癌において極めて重要です.
研究 の 目的:
- 癌におけるRTK/RAS/MAPKシグナル伝達のための代替サブセルラープラットフォームを調査する.
- 腫瘍性信号の新たなメカニズムを特定する.
主な方法:
- 癌細胞におけるキメリックRTKオンコタンパク質 (ALK,RET) の分析
- 新しいタンパク質の粒子の形成の特徴
- RASの活性化とシグナリング複合体の構成を評価するための生化学的測定
主要な成果:
- RTKオンコタンパク質は膜のない細胞質タンパク質の粒子を形成する.
- これらの粒子はRAS活性化複合体 (GRB2/SOS1) を濃縮しています.
- RASの活性化とMAPKのシグナリングは,これらの粒子の内の脂質膜とは独立して発生する.
結論:
- 膜のないタンパク質粒子は,腫瘍性RTKとRASシグナル伝達のための明確なプラットフォームとして機能する.
- 粒子の形成は腫瘍的シグナル出力に不可欠です.
- 特定されたタンパク質粒子の成分とRTKオンコタンパク質の形成規則
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