クレオソームの枯渇にもかかわらずミトスの染色体組み立て
Keishi Shintomi1, Fukashi Inoue2,3, Hiroshi Watanabe2
1Chromosome Dynamics Laboratory, RIKEN, Wako, Saitama 351-0198, Japan.
Science (New York, N.Y.)
|May 20, 2017
まとめ
ミトスの染色体組み立ては 核分裂体なしで起こり,以前の仮定に異議を唱えます クロマチド構造の形成に重要な役割を果たすコンデンシンは,核細胞組成が損なわれても,
科学分野:
- 細胞生物学
- 分子生物学
- 遺伝学
背景:
- 核細胞は真核染色体の基本単位である.
- ミトーシス過程で,クロマチンの繊維はミトーシス染色体内で棒状のクロマチドを形成する.
- ミトスの染色体形成のための核細胞組成の必要性は完全に理解されていません.
研究 の 目的:
- 核染色体の組み立てがミトの染色体の組み立ての前提条件であるかどうかを調査する.
- この過程におけるヒストンチャペロン Asf1の役割を調べる.
- 染色体形成における核細胞と凝縮体の相互作用を解明する.
主な方法:
- ヒストンチャペロンAsf1が欠乏した,細胞のない*Xenopus*卵のエキスを使用した.
- クロマチドのような構造を組み立てるためにマウス精子核と組み合わせたエキス.
- 主要なタンパク質の役割を評価するために,結合的な枯渇実験を行いました.
主要な成果:
- クロマチドのような構造は ニュクレオソームがほとんど存在しない状態で組み立てられました
- これらの"核素が枯渇した"染色体は,コンデンシンに富んだ中央軸を持っていた.
- 組み立てられた構造は,正常な,核細胞を含む染色体と比較して,より脆弱でした.
結論:
- 核染色体の組み立ては,ミトスの染色体と染色体の形成に厳格に不可欠ではありません.
- コンデンシンは核細胞から独立してミトクロモソームの構造的整合性にとって重要です.
- ミトの染色体組み立ての過程で 核細胞と凝縮体の間で 機能的な交信が起こります
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