エピスタティック・ドリフトは,タンパク質の進化の予測性を徐々に低下させる
Yeonwoo Park1, Brian P H Metzger2, Joseph W Thornton1,2,3
1Committee on Genetics, Genomics, and Systems Biology, University of Chicago, Chicago, IL, USA.
Science (New York, N.Y.)
|May 19, 2022
まとめ
進化のエピスタシスは タンパク質の配列の変化を 予測不可能にします ほとんどの変異効果は,目に見えるランダム性にもかかわらず,多くの弱い相互作用のために,徐々に予測可能に変化します.
科学分野:
- 進化生物学
- 分子生物学
- バイオ物理学
背景:
- エピスタティック相互作用は進化の予測を複雑にする.
- タンパク質の進化の過程で突然変異の効果がどのように変化するかに関するデータは限られている.
研究 の 目的:
- 進化するタンパク質の配列における変異効果の変化の範囲と時間的動態を調査する.
- 進化の軌道を形作る エピスタシスの役割を理解する
主な方法:
- フィロゲネティック・ディープ・ミューテーション・スキャニングが採用された.
- すべての可能なアミノ酸変異の機能的効果は,祖先と既存のステロイド受容体DNA結合領域で測定された.
主要な成果:
- 7億年以上,エピスタシスは突然変異の影響を解消し,その進化的アクセシビリティを変えた.
- ほとんどの変異効果は,多くの弱い表皮の相互作用によって,徐々に中性的に変化した.
- 予測不可能な状況にもかかわらず 進化過程は 十分なデータで 統計的に予測可能であることが示されました
結論:
- タンパク質配列の進化は,エピスタシスによる偶然性や予測不能性によって特徴づけられる.
- 進化の過程は複雑ですが 統計的に予測できます
- これらのダイナミクスを理解するには,遺伝学と実験データを統合する必要があります.
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