閉じたミトーシスには,核包膜の局所的な解体が必要である
Gautam Dey1, Siân Culley2, Scott Curran3
1MRC Laboratory for Molecular Cell Biology, London, UK. g.dey@ucl.ac.uk.
Nature
|August 28, 2020
まとめ
研究者達は 細胞が閉じたミトーシスで 核を分割する方法を発見しました Les1と呼ばれるタンパク質は 核膜の分解を制御することで 漏れを防ぎます
科学分野:
- 細胞生物学
- 分子生物学
- 遺伝学
背景:
- ユカリオット細胞はミトーシス中に複製されたゲノムを2つの新しい核に分割する.
- ミトーシスは"開いたミトーシス" (核包膜の分解/再組み) または"閉じたミトーシス" (核の再構成/分裂) のいずれかとして発生します.
- 閉じたミトーシス中の核封筒分裂のメカニズムは,ほとんど不明である.
研究 の 目的:
- 閉じたミトーシス中の核封筒分裂のメカニズムを解明する.
- 閉じたミトーシスにおける核分裂に関与する重要なタンパク質を特定する.
主な方法:
- 分裂酵母シゾサカロミセス・ポンベをモデル生物として利用した.
- 生体細胞の画像と 電子トモグラフィーを使った
- 核膜のダイナミクスにおけるLES1タンパク質の役割を研究した.
主要な成果:
- 閉じたミトーシスの核分裂は,子核をつなぐ橋の核毛穴の局所的な解体によって達成される.
- 核内膜に局限したタンパク質で 核内膜の分解をミッドゾーンに制限しています
- Les1は子核の分離から核の漏れを防ぐ.
結論:
- 閉じたミトーシスの局所的な核包膜分解のメカニズムは,開いたミトーシスと類似している.
- これは様々な真核生物の核再構成の保存メカニズムを示唆している.
- Les1は,閉じたミトーシス中の子核の整合性を確保する上で重要な役割を果たします.
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