E. coli RNAポリメラーゼによる転写停止と停止の単分子研究

R J Davenport¹, G J Wuite, R Landick

¹Department of Molecular and Cell Biology, University of California, Berkeley, CA 94720, USA.

Science (New York, N.Y.)

|March 31, 2000

まとめ

単一分子の研究は,RNAポリメラーゼが多様な転写率と一時停止行動を示すことを明らかにしています. リバーシブルな休止は,重要な中間状態として作用し,細菌と真核生物の遺伝子調節に影響を与えます.

科学分野:

分子生物学は分子生物学である.
バイオフィジックス生物物理学
遺伝学遺伝学とは

背景:

遺伝子調節は,RNAポリメラーゼによる転写の正確な制御に依存しています.
単一のRNAポリメラーゼ分子のダイナミックな振る舞いを理解することは,転写機構の解明に不可欠です.

研究の目的:

転写中の単一のRNAポリメラーゼ分子のリアルタイムダイナミクスを調査する.
個々のRNAポリメラーゼ分子の内在の転写率,一時停止傾向,停止行動を特徴づけること.
転写における運動的中間体としての一時停止の役割を調査する.

主な方法:

先進的な光学トラップ/フローコントロールビデオ顕微鏡技術を使用した.
Escherichia coliのRNAポリメラーゼの単一分子によるトランスクリプションをリアルタイムで拡張されたテンプレート長さで監視します.

主要な成果:

個々のRNAポリメラーゼ分子間の固有の転写率において有意な異質性を示した.
異なるRNAポリメラーゼ分子の間で,一時停止と終了の異なる傾向が観察されました.
活性延長と転写停止の間の重要な運動的中間体として,可逆的な一時停止を特定しました.
転写過程中のRNAポリメラーゼの構成性転移安定性を明らかにした.

結論:

単一分子転写の研究は,RNAポリメラーゼの行動の異質性についての重要な洞察を提供します.
RNAポリメラーゼの形状的柔軟性および停止ダイナミクスは,遺伝子調節に不可欠です.
この発見は,プロカリオット系と真核系の両方の遺伝子調節機構の理解に直接的な影響を及ぼします.

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