イーストのセントロメア結合タンパク質複合体の微小管運動活性
A A Hyman1, K Middleton, M Centola
1Department of Pharmacology, University of California, San Francisco 94143.
Nature
|October 8, 1992
まとめ
CBF3タンパク質複合体は,細胞分裂時にセントロメアDNAをマイクロチューブルと直接結びつける. この複合体はモーターとして機能し,ミトーシスにおける正確な染色体分離に不可欠です.
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.
- 遺伝学 遺伝学とは
背景:
- 細胞分裂中の染色体分離は,ミトスのスパインドルに依存しています.
- セントロメリックDNAを結合するタンパク質によって形成されたキネトコアは,染色体をスパインドルマイクロチューブルに結合します.
- 発芽酵母セントロメアのCDEIII領域は,染色体分離に不可欠です.
研究 の 目的:
- CBF3タンパク質複合体のインビトロ機能を調査する.
- ミトーシス中にセントロメアがマイクロチューブルにどのように結合するかを決定する.
主な方法:
- CBF3タンパク質複合体を分離するためにアフィニティクロマトグラフィー.
- キネトコア機能と微小管の相互作用を評価するためのインビトロアッセイ.
主要な成果:
- CBF3複合体は,CDEIII DNA配列に特異的に結合する.
- CBF3は,DNAを微小管に結合する能力をin vitroで実証しました.
- CBF3複合体はマイナスエンド向けマイクロチューブルベースのモーターを含んでいることが確認されました.
結論:
- 微小管ベースのモーターは,ミトーシス中の染色体と微小管の間の基本的なリンクである可能性が高い.
- CBF3複合体は,その運動活動を通じて染色体-微小管の結合を媒介する上で重要な役割を果たします.
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