通过一个短暂的无差别电的RNA-tethered酸光交叉连接
Karen L Buchmueller1, Brian T Hill, Matthew S Platz
1Department of Chemistry, University of North Carolina, Chapel Hill, North Carolina 27599-3290, USA.
Journal of the American Chemical Society
|September 4, 2003
概括
在RNA中的阿里拉酸光交叉连接揭示了一种胺胺中间体,而不是烯,负责 adduct 形成. 这种反应性物种有效地交叉链接RNA,使动态相互作用的结构映射成为可能.
科学领域:
- 生物化学 生物化学
- 分子生物学分子生物学
- 化学生物学 化学生物学
背景情况:
- 亚里化物光交联是检测RNA结构的关键技术.
- 在水溶液中的光交联过程中产生的确切的活性物种仍然不太清楚.
研究的目的:
- 阐明光激活的3-基乙酸和RNA之间 adduct 形成的机制.
- 描述负责RNA中光交联的反应性中间体.
主要方法:
- 用RNA结合的3-基烯酸的光解.
- 使用具有诊断反应性的试剂分析交叉链形成.
- 时间解析的光谱实验 (阿贡矩阵和溶液).
主要成果:
- 光解产生胺或阿泽皮中间体,而不是烯,形成跨链交叉链接.
- 这种中间体与RNA核酸 (腺素,尿素,瓜诺素) 广泛反应.
- 交叉链的形成是独立于局部RNA结构 (双重或单链).
- 介质的寿命 (60-160微秒) 比大规模的RNA折叠事件要短.
结论:
- 这项研究建立了阿里拉齐德介导的RNA光交联的机制框架.
- 鉴定到的胺胺中间体允许对RNA结构邻居和动态相互作用进行可靠的映射.
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