高 afinityのトポイソメラーゼI結合配列は,テトラヒメナR-クロマチニンのDNAaseI過敏部位にクラスタ化されています

B J Bonven, E Gocke, O Westergaard

Cell

|June 1, 1985

まとめ

トポイソメラーゼI酵素は,テトラヒメナ・サーモフィラにおける特定のDNA断裂を生成する.

科学分野:

分子生物学は分子生物学である.
遺伝学遺伝学とは
バイオケミストリーバイオケミストリー

背景:

トポイソメラーゼI (TOP1) は,DNA複製と転写において重要な役割を果たします.
TOP1は,過敏な部位を含む特定のDNA領域と相互作用することが知られている.

研究の目的:

テトラヒメナ・サーモフィラ (Tetrahymena thermophila) のDNAase I過敏部位とTOP1の関連性を調査する.
rDNAスペーサーでTOP1によって認識される特定のDNA配列を識別する.

主な方法:

浄化されたTOP1と分離されたrDNAを用いた酵素分析.
rDNAスペーサー内のDNA分裂部位の分析.

主要な成果:

TOP1は,rDNAスペーサーにおけるサイトおよびストランド固有の単一ストランド割れ目を導入します.
クリーバージは,過敏性サイト内の保存された六角形配列要素で発生します.
この元素は,r-クロマチンの高親和性TOP1結合部位として作用する.

結論:

繰り返しのシーケンス要素は,TOP1.0の特定の認識サイトとして機能します.
このTOP1認識メカニズムは,多様な真核生物体で保存されており,広範な生物学的役割を示唆しています.

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