サッカロマイセス・セレヴィシアのアナフェーズ前の姉妹ミニクロモソームDNAの構造
1Department of Genetics, University of Washington, Seattle 98195.
Science (New York, N.Y.)
|December 18, 1987
まとめ
DNAトポロジーは姉妹染色体を一緒に持たない. 研究によると,姉妹ミニクロモソームはアナフェーズ前に相互に繋がっていないが,それでも適切に分離し,以前の仮定に異議を唱えている.
科学分野:
- 分子生物学は分子生物学である.
- 細胞生物学 細胞生物学
- 遺伝学 遺伝学とは
背景:
- 姉妹染色体凝結は,細胞分裂中の正確な染色体分離に不可欠です.
- この結合を維持する上で,DNAトポロジー,特に相互接続の役割は議論されてきた.
- これらのメカニズムを理解することは,細胞循環の調節を理解し,アヌプロイド症の予防に不可欠です.
研究 の 目的:
- アナフェーズ前の姉妹染色体凝結のためのトポロジカル・インターロッキングの必要性を調査する.
- DNAトポロジーは姉妹染色体を一緒に保持する主要な力であるかどうかを判断する.
- 酵母細胞サイクル変異体における姉妹染色体分離を分析する.
主な方法:
- Saccharomyces cerevisiaeの細胞サイクル (cdc) 変異体におけるミニクロモソーム構造の分析.
- 停止した細胞における姉妹ミニクロモソームの相互鎖状態の顕微鏡検査.
- ミニクロモソームが細胞サイクル停止から解放されたときのプロイド分析.
主要な成果:
- 姉妹ミニクロモソーム分子は,S段階後のおよびアナフェーズ前の細胞で,大部分が相互に繋がっていないことが判明しました.
- 細胞サイクル停止から解放されると,これらの姉妹ミニクロモソームは正確に分離した.
- トポロジカル・インターロッキングの程度は,適切なセグレゲーションと相関しなかった.
結論:
- 姉妹DNA分子のトポロジカルな相互接続は,アナフェーズ前の適切な分離のために必要ありません.
- DNAのトポロジーは,姉妹染色体を一緒に保持する主なメカニズムである可能性は低い.
- 代替メカニズムは,アナフェーゼまで姉妹染色体の結束に責任がある必要があります.
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