ミュアンのBub1のキネトコア局所化は,正常なミトスのタイミングと,スパインドルの損傷に対するチェックポイント応答のために必要である
1Department of Cell Biology, Harvard Medical School, Boston, Massachusetts 02115, USA.
Cell
|May 30, 1997
まとめ
キネトコアにおけるミトーシスチェックポイントタンパク質 mBub1は,正常なミトーシスタイミングと,スパインドル損傷後の細胞死亡を防ぐために不可欠です. その破壊により,細胞はミトーシスをエラーで退去し,アポトーシスを回避することができます.
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.
- 遺伝学 遺伝学とは
背景:
- ミトスのチェックポイントは,すべての染色体が並べられるまで,早期のアナフェーズ発症を防ぐ.
- 細胞は通常,長時間スピンドル損傷とチェックポイント応答の失敗の後,アポトーシスを経験します.
研究 の 目的:
- ミトーシスと細胞運命におけるマウリンBUB1ホモログ (mBub1) の役割を調査する.
- チェックポイント応答とミトーシスタイミングにおけるmBub1の機能を決定する.
主な方法:
- ミトーシス中のキネトコアでmBub1の局所化研究.
- その機能を評価するために,支配的な負のmBub1変異体の発現.
- mBub1抑制後の細胞サイクル進行とアポトーシスの分析.
主要な成果:
- ミトーシス過程でマウリンBUB1 (mBub1) がキネトコアに局所化する.
- mBub1は,スパインドルの損傷チェックポイントと正常なミトシスタイミングに不可欠です.
- mBub1の機能が損なわれると,ミトスの脱出が,スパインドルの欠陥とアポトーシスの回避につながります.
結論:
- キネトコアに関連したmBub1はミトスの退去を調節する.
- ミトシスチェックポイントとG1アポプトシス経路の間には機能的なリンクが存在します.
関連する概念動画
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02:27The Mitotic Spindle
The mitotic spindle—or spindle apparatus—is a eukaryotic, cytoskeletal structure made up of long protein fibers called microtubules. Formed during cell division, the spindle separates sister chromatids and moves them to opposite ends of a parental cell, where the now individual chromosomes are distributed to two daughter cell nuclei.
The bipolar configuration of the mitotic spindle facilitates chromosomal segregation, preparing the cell for division. One mechanism that ensures bipolar mitotic...
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