プラスエンド方向のマイクロチューブルモーターによるミトティック・スピンドルの組織化
K E Sawin1, K LeGuellec, M Philippe
1Department of Biochemistry and Biophysics, University of California, San Francisco 94143.
Nature
|October 8, 1992
まとめ
キネシン状のタンパク質Eg5は,クセノプスの卵抽出物におけるミトーシス・スパインドルの組み立てに不可欠である. Eg5を枯渇させることは,スパインドル形成を阻害し,細胞分裂に不可欠なプラスエンド方向のマイクロチューブルモーターとしての役割を明らかにします.
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:
- キネシンのようなタンパク質を含む微小管のモータータンパク質は,ミトスのスパインドル機能に関与しています.
- ユカリオット細胞分裂,特にミトーシスにおけるキネシン関連タンパク質の特定の役割は,大部分が特徴づけられていない.
研究 の 目的:
- 顕微鏡検査を用いてミトーシス・スパインドル・アセンブリにおけるキネシン型のタンパク質Eg5の機能を調査する.
- クセノプスの卵抽出物におけるEg5の局所化と運動活性を決定する.
主な方法:
- Xenopusの卵エキスを使った in vitro スピンドルアセンブリアッセイを用いた.
- Eg5の免疫低下を施し,その役割を評価するために,anti-Eg5抗体を用いた.
- Eg5の微小管の運動活性を in vitro で測定した.
主要な成果:
- Eg5は,スパインドルのマイクロチューブルに局所化し,スパインドルのポールで濃縮されます.
- Eg5の免疫低下や,Anti-Eg5抗体の追加により,スパインドル形成が著しく低下した.
- Eg5はプラスエンド向けマイクロチューブルモーターとして機能します.
結論:
- Eg5はミトーシス中のスパインドル極のダイナミックな自己組織化に不可欠です.
- Eg5がスパインドルポール組織と機能を調節する新しいメカニズムを示唆しています.
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