細胞のインターフェーズにおいて,陰性細胞サイクル制御遺伝子の変異によってブロックされた細胞におけるスパインドル形成とクロマチンの凝縮
S A Osmani1, D B Engle, J H Doonan
1Department of Pharmacology, Robert Wood Johnson Medical School, UMDNJ, Piscataway 08854.
Cell
|January 29, 1988
まとめ
Aspergillus nidulans bimE7の変異は,早期ミトーシスを誘発し,SまたはG2段階で染色体の凝縮とスパインドル形成を引き起こします. この機能喪失変異は細胞周期制御を覆し,bimEがミトスのエントリーを否定的に調節することを示唆しています.
科学分野:
- 細胞生物学 細胞生物学
- 分子遺伝学 分子遺伝学
- 菌類の遺伝学 菌類の遺伝学
背景:
- 細胞循環は,DNA複製とミトーシスを通して秩序ある進行を保証します.
- Aspergillus nidulans の bimE7 のような温度感受性変異は,研究者が特定の条件下で重要な遺伝子を研究することを可能にします.
- 早期にミトーシスに突入すると,ゲノムの完全性が破壊されます.
研究 の 目的:
- 細胞周期調節におけるビムE遺伝子の機能を調査する.
- bimE7変異が正常な細胞周期のチェックポイントを回避するかどうかを判断する.
- ミトーシスの開始を制御するビムEの役割を明らかにする.
主な方法:
- bimE7とS/G2フェーズミュータントの間のダブルミュータントの構築.
- DNA複製を阻止するためにヒドロキシ尿素を用いた細胞周期の同期.
- アスペルギルス・ニドゥランスの染色体凝縮とスパインドル形成の顕微鏡分析.
主要な成果:
- bimE7変異は,SまたはG2フェーズで停止した細胞の染色体凝縮とスパインドル形成を誘発した.
- この早期のミトーシスイベントは,DNA複製がブロックされた場合でも発生しました.
- bimE7は機能喪失変異として確認されました.
結論:
- bimE7変異は,通常,早発ミトーシスを防ぐ細胞サイクル制御システムを覆す.
- bimE遺伝子は,潜在的に nimA遺伝子である陽性ミトシス誘発体の負の調節体として作用する可能性があります.
- bimEの機能を理解することで,DNA複製または修復中にミト菌の侵入を防ぐメカニズムについての洞察が得られます.
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