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転写活性DNAにおける再結合率の上昇
1Department of Genetics and Development, Columbia University College of Physicians and Surgeons, New York, New York 10032.
Cell
|February 24, 1989
まとめ
GAL10遺伝子の重複の構成的転写は,酵母におけるプラズミド損失を大幅に増加させる. しかし,この転写は変換イベントを強化しないため,繰り返しの内での転写開始が再結合を誘発することを示唆しています.
科学分野:
- 分子生物学は分子生物学である.
- イースト遺伝学 イースト遺伝学
- DNA再組み合わせ DNA再組み合わせ
背景:
- 繰り返されたDNA配列間の再結合は,ゲノム安定性における重要なプロセスである.
- 転写,特にRNAポリメラーゼII依存は,DNA再結合に影響することが知られている.
- Saccharomyces cerevisiae の GAL10 遺伝子は,転写-再結合相互作用を研究するためのモデルシステムを提供します.
研究 の 目的:
- GAL10遺伝子内の直接的な再結合に対するRNAポリメラーゼII依存転写の影響を調査する.
- GAL10遺伝子繰り返しの構成発現がプラズミド喪失と変換イベントに影響するかどうかを決定する.
- この再結合の調節における転写活性化剤 (GAL4) と抑制剤 (GAL80) の役割を特定する.
主な方法:
- GAL4またはGAL80のヌル変異を有する同位酵母菌株を使用した.
- リコンビネーション分析のために,統合された GAL10 遺伝子リピートを持つ構築株.
- 構成的および非構成的表現条件下で測定された再結合率 (プラズミド損失および変換).
- 転写開始部位の役割を評価するために,Northern blot分析を使用した.
主要な成果:
- GAL10遺伝子構造の構成的発現は,プラズミド喪失の割合を15倍に増加させた.
- 統合されたプラズミドの保持につながった変換イベントは,繰り返し表現によって刺激されませんでした.
- プロモーター変異の分析は,統合されたプラズミド配列内の転写開始が,観察された再結合刺激を媒介することを示した.
結論:
- RNAポリメラーゼII依存転写は,直接の繰り返しの間のプラズミド損失につながる再結合を大幅に強化します.
- 再結合に対する刺激効果は,繰り返された配列の中で発生する転写開始に依存しています.
- プラズミドの損失と変換の差異的な影響は,これらの再結合結果に異なるメカニズムが関与することを示唆しています.
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