2つの異なる染色体構造が,細胞周期を通してリボソームRNA遺伝子の中で共存しています
A Conconi1, R M Widmer, T Koller
1Institute for Cell Biology, Swiss Federal Institute of Technology, Zürich.
Cell
|June 2, 1989
まとめ
フレンド細胞は,2つの異なるリボソームクロマチンの構造を示します:ヌクレオソームを含む不活性コピーと非ヌクレオソーム活性遺伝子. これらの状態は,転写とは無関係に維持され,細胞サイクルを通じて伝播します.
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:
- リボソームクロマチンの構造は,遺伝子調節に極めて重要です.
- 細胞周期の異なる段階におけるクロマチンの状態を理解することは不可欠です.
研究 の 目的:
- フレンド細胞におけるリボソームクロマチンの構造的組織を調査する.
- 異なったクロマチンの構造が転写活動と相関するかどうかを判断する.
- 細胞サイクルを通してこれらの構造の安定性を評価する.
主な方法:
- プソラレン・フォトクロスリンクリングは,リボソームクロマチンの構造を分析するために使用されました.
- クロマチンは,指数関数的に成長する細胞,静止細胞,およびメタフェーズ染色体で調べられました.
主要な成果:
- 2つの異なるリボソームクロマチンのタイプが特定されました:ニュクレオソームを含む (不活性) と重複構造がない (転写).
- 個々の遺伝子コピーは,活性状態または非活性状態のいずれかに存在します.
- これらの状態の相対的な割合は,インターフェーズとメタフェーズで一貫性がありますが,それらの転写活動は異なります.
結論:
- リボソームクロマチンは,進行中の転写から独立して,少なくとも2つの安定した状態に存在する.
- これらのクロマチンの状態は安定して維持され,細胞サイクルを通して伝播されます.
- これは,遺伝子発現レベルに関係なく,異なる染色体構成を維持するメカニズムを示唆しています.
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