选择性前生物的RNA胺和DNA纯核酸的形成
Jianfeng Xu1, Václav Chmela1, Nicholas J Green1
1MRC Laboratory of Molecular Biology, Cambridge Biomedical Campus, Cambridge, UK.
Nature
|June 5, 2020
概括
研究人员在前生物条件下合成了RNA和DNA构建块. 这支持混合RNA-DNA早期遗传系统的理论,在生命出现之前可能共存.
科学领域:
- 生命研究的起源
- 前生物化学
- 分子进化
背景情况:
- 第一个遗传聚合物的起源是有争议的",RNA世界"理论认为RNA是最初的可复制分子.
- 其他理论认为,涉及RNA和DNA的异质遗传系统可能是生命的先驱.
- 混合系统需要RNA和DNA构建块的同时非生物合成.
研究的目的:
- 为了证明精氨酸脱氧核化物 (deoxyadenosine和deoxyinosine) 的选择性益生菌合成.
- 研究与现有的胺核酸合合成的精氨酸脱氧核酸.
- 在前生物时代提供支持潜在混合RNA-DNA遗传系统的证据.
主要方法:
- 使用了正规胺核酸合成的关键中间体.
- 开发了一种高产量,立体选择性和区域选择性的前生物合成途径.
- 分析了核酸的混合物,以确认氨酸脱氧核酸和氨酸核酸的存在.
主要成果:
- 实现了脱氧腺和脱氧氨的高产益生菌合成.
- 已经证明,在纯氨酸脱氧核酸合成过程中,氨酸核酸 (cytidine,uridine) 仍存在.
- 从单一的合成过程中获得含有纯氨酸脱氧核酸和胺核酸的混合物.
结论:
- 这些发现支持了在生命出现之前素脱氧核化物和胺核化物共存的可能性.
- 这项研究为DNA和RNA前体的非生物合成提供了可信的途径.
- 结果强化了异质遗传系统作为生命起源的早期阶段的假设.
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