人間の胚の肢体における系統特有の規制活動の進化
Justin Cotney1, Jing Leng, Jun Yin
1Department of Genetics, Yale University School of Medicine, New Haven, CT 06520, USA.
Cell
|July 6, 2013
まとめ
人間の四肢の発達は,ヒトに特有の遺伝子調節活動が得られたことを示しています. プロモーターとエンハンスターの活動におけるこれらの変化は,おそらく人間の形態学的進化を駆動する.
科学分野:
- 進化生物学の進化生物学について
- 発達生物学 発達生物学とは
- ゲノミクスゲノミクスとは
背景:
- 人間の解剖学的進化は,発達の遺伝子調節の変化と関連しています.
- 人間が進化した特定の規制機能は十分に理解されていません.
研究 の 目的:
- ヒトの胚性肢体の発達における全ゲノム規模のシス調節進化を調査する.
- 遺伝子調節要素の活性におけるヒト特有の変化を特定する.
主な方法:
- ヒストンの改変H3K27ac (活性プロモーターおよび強化剤のマーカー) をヒト,レサス,マウスの胚性肢体の発達と比較した.
- H3K27acの変化を分析し,ヒトの血統におけるプロモーターおよび強化剤の活性増加を定量化しました.
主要な成果:
- ヒトの血統系におけるプロモーターの13%,エンハンスターの11%の活性向上が,レサス猿からの分岐以来,確認された.
- これらの獲得は,改変された祖先の活動または他の組織からのコオプションから生じたことを観察しました.
- ヒトが獲得した強化剤のほとんどは哺乳類内で発生したことが判明しました.
- リンクされたプロモーターと強化剤は,ヒトの肢体における遺伝子発現を増加させる.
結論:
- 重要なシス調節進化は,獲得されたプロモーターとエンハンサーの活動によって特徴付けられ,ヒトの肢体で発生しました.
- これらの調節の変化は,遺伝子発現の増加と関連しており,ヒトの形態学的進化の重要な分子駆動因子を代表する可能性があります.
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