制御DNAのヒト特異的喪失とヒト特異的な特徴の進化
Cory Y McLean1, Philip L Reno, Alex A Pollen
1Department of Computer Science, Stanford University, Stanford, California 94305, USA.
Nature
|March 11, 2011
まとめ
人間の進化には,保存された非コーディングDNAの削除を含む特定の遺伝的変化が含まれていました. 重要な遺伝子の近くのこれらの削除は,脳の発達の変化や特定の解剖学的特徴の喪失などのヒト特有の特徴と相関しています.
科学分野:
- 進化生物学の進化生物学について
- ゲノミクスゲノミクスとは
- ヒューマン・ジェネティクス ヒューマン・ジェネティックス
背景:
- 人間特有の特徴の遺伝的基礎を理解することは,進化論の研究にとって極めて重要です.
- 非コーディングDNAの規制要素は,表型進化において重要な役割を果たします.
- 以前の研究では,加速された配列変化とヒトの異なった遺伝子発現を特定しました.
研究 の 目的:
- ヒト特有の規制変更を促す可能性のある特定の分子イベント,特に保存された非コーディング領域の削除を特定する.
- これらの削除と人間の進化的適応の間の相関を調査する.
主な方法:
- 比較ゲノミクス:人間と他の哺乳類 (チンパンジーなど) の全ゲノム比較.
- 他の哺乳類で高度に保存されているヒトの削除された配列の識別.
- これらの削除の位置と潜在的な規制機能を分析し,遺伝子の近くの非コーディング領域に焦点を当てます.
主要な成果:
- 哺乳類全体で保存されている配列の510の完全な削除をヒトで特定し,主に非コーディング領域で.
- 削除は,ステロイドホルモンシグナル伝達と神経機能に関与する遺伝子の近くで濃縮された.
- 特定の欠損は,アンドロゲン依存の感受性ビブリスアおよびペニル脊椎の喪失 (アンドロゲン受容体遺伝子の近く) および脳の領域の拡張の変化 (GADD45G遺伝子の近く) と関連付けられました.
結論:
- 保存された強化剤の完全な削除は,ヒトの進化に貢献する重要な分子イベントです.
- これらの削除は,先祖の特徴の喪失と新しい特徴の獲得の両方に繋がる可能性があります.
- この研究は,人間の分岐を形作る規制不活性化イベントの具体的な例を提供します.
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