膜横断フォスフォタンパク質Cbpは,Src族のチロシンキナーゼの活動を調節する
M Kawabuchi1, Y Satomi, T Takao
1Division of Protein Metabolism, Institute for Protein Research, Osaka University, Suita, Japan.
Nature
|May 9, 2000
まとめ
新しく発見されたタンパク質Cbpは,細胞質Cskと膜関連Src-PTKsの相互作用を促進する. この相互作用は,Src-PTKの活動を制御することによって,細胞の成長と分化を調節するために重要である.
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:
- Src族のタンパク質チロシンキナーゼ (Src-PTKs) は,真核細胞の成長と分化を調節する.
- Cskは,特定のチロシン残基をリン酸化することによって,Src-PTKの活性を否定的に制御する.
- 細胞質Cskと膜関連Src-PTKの間には局所化ギャップが存在する.
研究 の 目的:
- CskとSrc-PTKsの相互作用のメカニズムを調査する.
- Src-PTKの活性調節に関与する新しいタンパク質を特定する.
主な方法:
- SH2ドメイン結合アッセイを用いたタンパク質相互作用の研究.
- プラズマ膜領域におけるCbpの局所化に関する研究.
- Csk媒介によるc-Srcの抑制をCbpの存在で分析する.
主要な成果:
- Csk.のSH2ドメインと結合するトランスメブランフォスフォタンパク質であるCbpを特定しました.
- Csk.の膜局所化におけるCbpの役割を実証した.
- 示されたCbpは,c-Src活動のCsk依存的阻害を媒介する.
- 局所化されたCbpは,信号伝達に関与するGM1のギャングリオシド濃縮膜ドメインに.
結論:
- Cbpは,細胞質Cskを膜関連Src-PTKと結びつける新しい成分である.
- Cbpは,Src-PTKsに関するCSKの規制機能を容易にしています.
- Cbpは,シグナル伝達に関連する膜マイクロドメイン内の Src-PTK 活動を制御する役割を果たします.
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