CTDのチロシンリン酸化は,RNAポリメラーゼIIへの終結因子徴募を阻害する

Andreas Mayer¹, Martin Heidemann, Michael Lidschreiber

¹Gene Center and Department of Biochemistry, Center for Integrated Protein Science Munich, Ludwig-Maximilians-Universität München, Feodor-Lynen-Strasse 25, 81377 Munich, Germany.

Science (New York, N.Y.)

|June 30, 2012

まとめ

RNAポリメラーゼIIによるRNAポリメラーゼII

科学分野:

分子生物学は分子生物学である.
遺伝子発現の表現について
バイオケミストリーバイオケミストリー

背景:

RNAポリメラーゼIIのC端領域 (CTD) は,リクルート因子によって転写を調節する.
CTDには保存されたヘプタペプチドの繰り返しが含まれています.
CTDのリン酸化パターンは,転写サイクルを調整するために極めて重要です.

研究の目的:

イーストRNAポリメラーゼII CTD.の新たなリン酸化部位を調査する.
トランスクリプション中の因子募集に対するTyr(1) リン酸化の機能的影響を決定する.
トランスクリプションサイクル相の調整におけるCTDリン酸化の役割を解明する.

主な方法:

酵母におけるリン酸化RNAポリメラーゼIICTDの分析.
CTDに結合する因子を評価するための生化学分析.
クロマチン免疫プレシピテーションは,生体内のリン酸化パターンをマップする.

主要な成果:

イーストRNAポリメラーゼIICTDは,他の部位に加えて,Tyr(1) でリン酸化される.
Tyr(1) リン酸化は延長因子Spt6結合を強化する.
Tyr(1) リン酸化は,終結因子Nrd1,Pcf11,Rtt103.3の募集を阻害する.
CTD Tyr(1) リン酸化は転写中に空間的に調節され,遺伝子ボディからの終結因子を除く.

結論:

TyrをはじめとするCTDのリン酸化は,重要な規制メカニズムとして作用する.
異なったリン酸化パターンは,因子採用と転写サイクル進行を決定する.
拡張されたCTDコードは,Tyr(1),Ser(2) とSer(5) のリン酸化を基に,転写の調整を説明しています.

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