レトロトランスポゾン膨張の波は,複数の哺乳類の系統におけるゲノム組織とCTCF結合を改造する
Dominic Schmidt1, Petra C Schwalie, Michael D Wilson
1Cancer Research UK, Cambridge Research Institute, Li Ka Shing Centre, Robinson Way, Cambridge CB2 0RE, UK.
Cell
|January 17, 2012
まとめ
この研究では,哺乳類の間で保存されたCTCF結合部位を特定し,古代のレトロエレメントがこれらの規制DNA要素の拡散を促し,ゲノム進化を形作っていることを明らかにしました.
科学分野:
- ゲノミクスゲノミクスとは
- 進化生物学の進化生物学について
- 分子生物学は分子生物学である.
背景:
- CTCF結合部位は,進化的に制約されている重要な規制DNA要素です.
- その保存とゲノム拡散を理解することは,ゲノム進化の解読の鍵です.
研究 の 目的:
- 特定のモチーフを含むCTCF結合サイトの全スペクトルを定義します.
- 複数の哺乳類の種間で保存されたCTCF結合場所を特定する.
- CTCFのバインディングの拡大と進化におけるレトロエレメントの役割を調査する.
主な方法:
- 6種の哺乳類のCHIP-seqデータによる比較分析.
- 堅固なモチーフを使用して保存されたCTCF結合部位の識別.
- CTCFのサイトに関連する繰り返し要素を検出するためのバイオ情報分析.
主要な成果:
- 5千以上の高度に保存され,頑丈で,組織独立のCTCF結合部位が特定されました.
- レトロエレメントの活性化により,ネズミ,犬,オポッサムにおけるCTCF結合の種特有の拡張が生じることが判明した.
- これらの拡張されたCTCF結合部位は,しばしばクロマチンと転写の絶縁体として機能する.
- 化石化した重複元素は,深く保存されたCTCF結合領域の側面で発見され,古代のレトロトランスポゾン活性を示しています.
結論:
- 繰り返しの駆動による分散は,哺乳類のゲノム進化における根本的な,古代の,そして活発なメカニズムである.
- レトロトランスポゾン活動は,哺乳類の進化を通して,CTCF結合部位の分布と機能を形作っています.
- CTCF結合部位は,ゲノム構造を維持し,進化の過程で遺伝子発現を調節する上で重要な役割を果たします.
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