KRAB 亜鉛指タンパク質は,遺伝子制御ネットワークの進化に寄与する
Michaël Imbeault1, Pierre-Yves Helleboid1, Didier Trono1
1School of Life Sciences, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland.
Nature
|March 9, 2017
まとめ
クリュッペル関連ボックス (KRAB) ドメインを含む亜鉛指タンパク質 (KZFPs) は,移植可能な要素と共に進化し,種特有の表遺伝子調節を形成した. これらのKZFPは 進化の軍拡競争が終わった後も 遺伝子を制御するために 古代の侵入者を利用しています
科学分野:
- 進化的ゲノミクス
- エピジェネティクス
- 遺伝子調節
背景:
- クリュッペル関連ボックス (KRAB) ドメインを含む亜鉛指タンパク質 (KZFPs) は,ヒトゲノムで急速に進化する遺伝子ファミリーによって暗号化されています.
- KZFPは,TRIM28とH3K9me3依存のヘテロクロマチン形成を通じて,胚性幹細胞 (ES) の移植可能な要素を抑制することが知られている.
- 宿主と移植可能な要素の間の進化的軍拡競争が,KZFP遺伝子の選択を誘導すると仮定されている.
研究 の 目的:
- 脊椎動物におけるKZFP遺伝子の進化的出現を,系統遺伝学およびゲノム学的アプローチを用いて調査する.
- ヒトゲノムのKZFP標的を特定し,その機能的役割を理解する.
- KZFP,トランスポーザブル要素,および表遺伝子調節の相互作用を解明する.
主な方法:
- KZFP遺伝子の進化史を追跡する 系統遺伝分析
- ヒトゲノムにおけるKZFP結合標的を特定するためのゲノム研究
- KZFPsと他の転写変調剤の相互作用の分析
主要な成果:
- KZFPファミリーのルーツは,コエラカンタとテトラポッドの共通の祖先に再割り当てられました.
- ほとんどのKZFPは,トランスポーザブルな要素に結合し,一部は進行中の共同進化を示していますが,多くのターゲットはトランスポーザブルな可能性を失っています.
- KZFPは,管理プラットフォームとして保存されたトランスポーザブル要素の断片を使用し,最初のホスト-侵入者紛争を超えた役割を果たしています.
結論:
- KZFPsとトランスポーザブル要素は,長期的な進化的パートナーシップを結んでいます.
- KZFPは,主に種に限定された表遺伝子調節層を確立するのに寄与する.
- この研究は古代の遺伝子要素を含む 遺伝子調節の新たなメカニズムを明らかにしています
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