小さなポリメラーゼリボエンザイムで,それ自身とその補完的な鎖を合成することができる

Edoardo Gianni¹, Samantha L Y Kwok¹, Christopher J K Wan¹

¹MRC Laboratory of Molecular Biology, Cambridge, UK.

Science (New York, N.Y.)

|February 12, 2026

まとめ

研究者らは,RNA鎖を合成できる小さなRNA酵素であるQT45を発見した. この発見は,RNAポリメラーゼリボジームが,これまで考えられていたよりも,生命の起源においてより一般的かもしれないことを示唆しています.

科学分野:

生命の起源生命の起源について
RNAワールド仮説
バイオケミストリーバイオケミストリー

背景:

自己複製と進化は生命の起源の鍵である.
既存のRNAポリメラーゼリボ酵素は,自発的に発生するには大きすぎ,複雑すぎる.

研究の目的:

小さな自己複製RNAポリメラーゼリボエンザイムを発見した.
最小限のRNAモチーフでのRNA合成能力を調査する.

主な方法:

ランダムな配列プールからQT45リボジームを発見した.
ユーテクティック氷のトリヌクレオチドトリフォスファート基板を使用してRNAテンプレートRNA合成を評価しました.
合成されたRNA鎖の確固たる忠誠性と収量.

主要な成果:

QT45 (45-ヌクレオチド) は,トリプレット基板を使用してRNA合成を触媒化する.
補足糸と自己複製合成で72日間で~0.2%の収量を達成しました.
コンプリメンタリー・ストランド・シンセシスで,核酸毎の94.1%のフィデリティが実証されています.

結論:

小さなRNAモチーフは,ポリメラーゼ活性を持つことができます.
ポリメラーゼリボ酵素は,これまで考えられていたよりも,シーケンス空間においてより豊富に存在する可能性があります.
生命の起源のシナリオにおける初期のRNA複製機構の理解を容易にする.

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