トランスクリプション-複製の衝突方向化はRループレベルを調節し,明確なDNA損傷応答を活性化します
Stephan Hamperl1, Michael J Bocek1, Joshua C Saldivar1
1Department of Chemical and Systems Biology, Stanford University School of Medicine, Stanford, CA 94305, USA.
Cell
|August 13, 2017
まとめ
DNAの転写と複製の衝突は DNAの損傷を引き起こします Rループは転写中に形成され,これらの衝突を悪化させ,DNAの断裂とゲノムの不安定性をもたらします.
科学分野:
- 分子生物学
- 遺伝学
- ゲノミクス
背景:
- トランスクリプション-複製の衝突はDNA損傷の主要な原因です.
- 共同転写RNAループ (Rループ) は,複製フォークの進行を阻害することによって,これらの衝突を悪化させる可能性があります.
研究 の 目的:
- 衝突指向とRループ形成がヒト細胞のゲノム安定性にどのように影響するかを調査する.
- 複製ストレス中のRループダイナミクスの調節におけるレプリソームの役割を明らかにする.
主な方法:
- ヒトの細胞で定義されたエピソム系を利用した.
- トランスクリプション-複製の衝突中にDNAの断裂とDNA損傷の反応を分析した.
- コディレクション (CD) とヘッドオン (HO) で評価されたRループ形成.
主要な成果:
- Rループは,通常の転写複合体とは異なり,DNAの断裂と指向特異的なDNA損傷反応を誘発する.
- レプリソームはRループレベルを差異的に調節し,CDのレベルを低下させ,HOのレベルを上昇させます.
- 複製のストレスと異常な発火はHO衝突を増加させ,ゲノム不安定化Rループにつながります.
結論:
- DNA複製はRループホメオスタシスにおいて重要な役割を果たします.
- 複製のストレスは,正面衝突時にRループの蓄積によってゲノム不安定化に寄与する.
- 発見は,癌のような疾患における 規制解除されたDNA複製と ゲノム不安定の間のメカニズム的なリンクを提供します.
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