C2'-水素原子抽象化後の急速なRNA鎖分裂
Rakesh Paul1, Marc M Greenberg
1Department of Chemistry, Johns Hopkins University , 3400 North Charles Street, Baltimore, Maryland 21218, United States.
Journal of the American Chemical Society
|January 13, 2015
まとめ
C2'-ヌクレオチド・ラジカルは,放射線被曝後にRNAの直接鎖断裂を引き起こします. これは,DNAと比較して,RNAの電離放射線損傷に対するより高い感受性を説明します.
科学分野:
- バイオケミストリー バイオケミストリー
- 放射線化学 放射線化学
- 分子生物学は分子生物学である.
背景:
- C2 eal-cdot-ヌクレオチドラジカルは,RNA鎖の断裂形成の中間物質として関与しています.
- RNAはDNAよりも電離放射線に対して脆弱であることが知られている.
研究 の 目的:
- C2 eal-cdot-ヌクレオチドラジカルによって媒介されるRNAにおける直接鎖断裂形成のメカニズムを調査する.
- RNAの鎖分裂化学をDNAの鎖分裂化学と比較する.
主な方法:
- ケトン前駆体の光分解を用いた単一および二重鎖RNAにおけるウリジン-2 eal-cdot-yl 根元 (1) の生成.
- C3 eal-cdot-carbon-oxygen bondのヘテロリチク割れによる鎖断裂形成の調査.
- O2またはβ-メルカプトエタノールによってラジカル1を捕まえる競争実験.
主要な成果:
- RNAの直接鎖の断裂は,C3 eal-cdot-carbon-oxygen bondのヘテロリティックな割れから生じる.
- リン酸の除去とウラシルの喪失は,鎖分裂と競合しないため,急速な割れ動力学 (>10(6) s(-1)) を示す.
- 発生したウリジン-2 eal-cdot-yl 基質の化学反応は,RNAの鎖分裂に対する感受性がDNAよりも高いことを説明する.
結論:
- C2 eal-cdot-ヌクレオチドラジカルは,電離放射線によって誘発される直接的なRNA鎖の断裂における重要な中間物質である.
- C3 eal-cdot-carbon-oxygen bondの急速な断裂は,鎖分裂の主要な経路である.
- このメカニズムは,RNAとDNAの間の観測された異なる放射性感受性を説明する.
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