RNA ピリミジンとDNA ピューリン核酸の選択的な前生物学的形成
Jianfeng Xu1, Václav Chmela1, Nicholas J Green1
1MRC Laboratory of Molecular Biology, Cambridge Biomedical Campus, Cambridge, UK.
Nature
|June 5, 2020
まとめ
研究者は RNAとDNAの両方のビルディングブロックを プリバイオティックな条件下で合成しました これは RNAとDNAが混ざり合って 生命が誕生する前に 潜在的に共存していたという説を裏付けている.
科学分野:
- 生命 研究 の 起源
- 前生物化学
- 分子 進化
背景:
- 最初の遺伝子ポリマーの起源は議論されており",RNA世界"理論では,RNAが最初の複製可能な分子であると主張されている.
- 代替理論は,RNAとDNAの両方を含む異質な遺伝系が生命に先行した可能性があることを示唆しています.
- 混合システムでは,RNAとDNAの両方の構成要素を同時に合成する必要があります.
研究 の 目的:
- ピューリンデオキシリボヌクレオシド (デオキシアデノシンとデオキシニノシン) の選択的プレバイオティック合成を実証する.
- 既存のピリミジンリボヌクレオシドとピューリンデオキシリボヌクレオシドの共合成を調査する.
- プリバイオティクスの時代の 混合RNA-DNA遺伝システムを 支持する証拠を提供すること
主な方法:
- 標準的なピリミジンリボヌクレオシド合成の主要中間物質を使用した.
- 高収量,ステレオ選択,および地域選択のプリバイオティック合成経路を開発した.
- ニュクレオシドの混合物を分析して,ピューリン・デオキシリボヌクレオシドとピリミジン・リボヌクレオシドの両方の存在を確認した.
主要な成果:
- デオキシアデノシンとデオキシニノシンを合成した
- ピリミジンリボヌクレオシド (シチジン,ウリジン) が,ピューリンデオキシリボヌクレオシド合成中に持続することを実証した.
- 単一の合成プロセスから,ピューリンデオキシリボヌクレオシドとピリミジンリボヌクレオシドの両方を含んだ混合物を得ました.
結論:
- この発見は,生命の出現前に purin deoxyribonucleosidesと pyrimidine ribonucleosidesが共存していた可能性を支持する.
- この研究は,DNAとRNAの前駆体の両方の非生物的合成のための妥当な経路を提供します.
- この結果は 生命の起源の初期段階として 異質な遺伝子システムという仮説を 強化している.
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