CAAXモチーフに加えて,p21rasをプラズマ膜に局所化させるには,多塩基ドメインまたはパルミトイロ化が必要です
J F Hancock1, H Paterson, C J Marshall
1Department of Haematology, Royal Free Hospital School of Medicine, London, England.
Cell
|October 5, 1990
まとめ
Rasタンパク質は,膜結合のために,翻訳後の修正を必要とします. 異なる超変性ドメインは,特定のプラズマ膜ターゲティングのために,パルミトイレーションまたはポリベースドメインのような明確な信号を提供します.
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:
- Rasタンパク質は,細胞シグナル伝達の主要な調節因子である.
- C端末のCAAXモチーフを含む翻訳後の改変は,rasタンパク質の機能にとって極めて重要です.
- ハイパー変性ドメインは,異なるras isoformsを区別し,その局所化に影響を与える.
研究 の 目的:
- ラスタンパク質の超変性ドメインが,プラズマ膜の局所化を媒介する明確なメカニズムを解明する.
- ras超変域内の新しいプラズマ膜ターゲティング信号を特定する.
主な方法:
- ラスタンパク質の翻訳後の改変の分析.
- 膜結合における超変性ドメインの役割を調査する.
- 新しいターゲティング信号の識別と特徴付け.
主要な成果:
- CAAXモチーフと組み合わせた,超変性ドメイン内のパルミトイレーション部位は,p21H-ras,p21N-ras,およびp21K-ras (A) の特定のプラズマ膜局所化をターゲットにします.
- パルミトイロ化が欠けているp21K-ras(Bの超変性ドメイン内の新しい多塩基ドメインも,プラズマ膜ターゲティングのためのCAAXモチーフと連携しています.
- 超変性ドメインが,rasタンパク質のプラズマ膜の局所化に明確なシグナルを提供することを実証した.
結論:
- ラスタンパク質の超変性ドメインには,同位体特異の信号が含まれており,それがプラズマ膜のターゲティングを決定する.
- これらの独特の標的付け信号は,異なるrasタンパク質の適切な局所化と機能を保証します.
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