トポイソメラーゼI活性によって調節されるリガンド依存増強剤の活性化
Janusz Puc1, Piotr Kozbial1, Wenbo Li1
1Howard Hughes Medical Institute, Department of Medicine, School of Medicine, University of California, San Diego, La Jolla, CA 92093-0648, USA.
Cell
|January 27, 2015
まとめ
研究者らは,DNAトポイソメラーゼI (TOP1) によってDNAをニッキングすることが,エンハンサーを活性化させ,エンハンサーRNA (eRNA) を合成するために不可欠であることを発見しました. このプロセスは,ダイヒドロテストステロン (DHT) とアンドロゲン受容体 (AR) によって誘発され,DNA修復機構の採用を伴う.
科学分野:
- 分子生物学は分子生物学である.
- エピジェネティクス エピジェネティクス
- がん生物学 がん生物学
背景:
- 増強剤は,遺伝子発現を制御する規制性DNA要素である.
- 増強剤は転写単位として機能し,増強剤RNA (eRNA) を生成する.
- リンガンド依存増強剤の活性化のメカニズムは,まだ完全に理解されていません.
研究 の 目的:
- リンガンド依存増強剤活性化の分子メカニズムを解明する.
- eRNA合成と強化機能におけるDNAトポイソメラーゼI (TOP1) の役割を調査する.
- デヒドロテストステロン (DHT) 誘発されたアンドロゲン受容体 (AR) が前立腺がん細胞に結合することを用いてこのメカニズムをモデル化します.
主な方法:
- 使用されたダイヒドロテストステロン (DHT) は,前立腺がん細胞のエンハンサーにアンドロゲン受容体 (AR) 結合を誘導する.
- DNAトポイソメラーゼI (TOP1),ATR,MRN複合体のAR調節強化剤への誘導をモニターした.
- トップ1のDNAニッキング活動がeRNA合成とエンハンサー活性化に与える影響を評価した.
主要な成果:
- DHT誘導から数分以内に,AR調節強化剤にTOP1の急速なリクルートが実証されています.
- TOP1のDNAニッキング活動は,堅固なeRNA合成とエンハンサー活性化のための前提条件であることを確認した.
- TOP1の募集に続いてATR,MRN複合体,DNA損傷修復装置の調整された募集が観察されました.
結論:
- eRNA合成中のトルションストレスを軽減するためにTOP1媒介のDNAニッキングを含むリガンド依存エンハンサー活性化の新しいメカニズムを明らかにしました.
- ERNA合成とAR-bound強化剤依存転写の調節におけるTOP1活動との直接的な関連性を強調した.
- このニッキング戦略が,AR駆動がんにおける eRNA発現と転写プログラムに定量的に影響を及ぼすことを示唆している.
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