細胞移動におけるシグナル伝達の空間的制限のために,Racの内細胞的トラフィックは必要である
Andrea Palamidessi1, Emanuela Frittoli, Massimiliano Garré
1IFOM, Fondazione Istituto FIRC di Oncologia Molecolare, Via Adamello 16, 20139 Milan, Italy.
Cell
|July 11, 2008
まとめ
Rab5媒介のエンドサイトーシスとRac GTPaseシグナル伝達は,細胞移動と関連しています. この研究では,Rab5が初期エンドソームにおけるRacの活性化を制御し,細胞の動きと形態学を制御する方法を明らかにしました.
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.
- 発達生物学 発達生物学とは
背景:
- 小型GTPases Rab5とRacは,エンドサイトーシスとアクチンの改造に不可欠です.
- 細胞内信号伝達の空間的制御は,分極化された細胞機能に不可欠である.
研究 の 目的:
- Rab5媒介のエンドサイトーシスと,モトジェニック刺激への反応としてRacの活性化との関連を調査する.
- Rac依存シグナル伝達と細胞移動の調節における膜トラフィックの役割を明らかにする.
主な方法:
- クラスリン媒介性エンドサイトーシスとRab5依存性経路を利用した.
- RacGEF Tiam1の初期エンドソームへの勧誘を調査した.
- プラズマ膜へのRacのリサイクルと,その後のアクチンの改造が観察されました.
- 哺乳類の腫瘍細胞と斑馬魚の原始生殖細胞におけるRab5-to-Rac回路を調べました.
主要な成果:
- クラトリンとRab5媒介のエンドサイトーシスは,モトジェニック刺激によるRacの活性化に必要である.
- Racの活性化とTiam1のリクルートメントは,初期のエンドソームで起こります.
- プラズマ膜へのRacの循環は,局所的なシグナル伝達とアクチンベースの突起を促進します.
- Rab5-to-Rac経路は,運動性腫瘍と生殖細胞の細胞形態を調節する.
結論:
- Racの膜取引は,Rac依存のモトジェニック信号の空間解像度にとって不可欠である.
- Rab5-to-Rac回路は,多様な細胞タイプと生物の移住プログラムを調節する上で重要な役割を果たしています.
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