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Updated: Jun 22, 2025

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MicroRNA-based Regulation of Picornavirus Tropism
Published on: February 6, 2017
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由阿斯加德考古阿尔戈诺特人进行的RNA引导RNA沉默
Carolien Bastiaanssen1, Pilar Bobadilla Ugarte2, Kijun Kim1
1Department of BioNanoScience, Kavli Institute of Nanoscience, Delft University of Technology, Delft, The Netherlands.
Nature communications
|July 1, 2024
概括
来自Lokiarchaeota的古代考古PIWI蛋白质执行RNA引导的基因沉默,为阿尔戈诺特蛋白质的进化和早期真核生物基因调节机制提供了洞察力.
科学领域:
- 分子生物学分子生物学
- 进化生物学 进化生物学
- 基因组学就是基因组学.
背景情况:
- 阿尔戈纳特蛋白质是真核RNA引导RNA沉默通路的关键作用体,对于基因抑制和防御至关重要.
- 细胞阿尔戈纳特被分为AGOs (miRNA/siRNA) 和PIWIs (piRNA),但它们的进化起源和分歧仍然不清楚.
- 了解基于阿尔戈诺特的沉默机制的早期演变对于破译真核生物的出现至关重要.
研究的目的:
- 调查阿斯加德古生物中的阿尔戈诺特蛋白质的进化历史和功能能力,这是真核生物的最接近的原生生物亲属.
- 来自Lokiarchaeon"Candidatus Harpocratesius repetitus"的深分支PIWI蛋白 (HrAgo1) 的特征及其在RNA沉默中的作用.
- 为了阐明PIWI蛋白质的祖先分子结构,先于真核生物AGO和PIWI类的分歧.
主要方法:
- 对阿斯加德古生物的基因组分析,以确定阿尔戈诺特蛋白扩张.
- 人类细胞中Lokiarchaeon HrAgo1的表达,以评估其与miRNA前体的基因沉默活性.
- 低温电子显微镜 (cryo-EM) 用于确定HrAgo1.1的结构.
- 量化单分子实验分析蛋白质-RNA相互作用和标结合模式.
主要成果:
- 在阿斯加德古生物中发现了阿尔戈诺特蛋白的进化扩张,包括一个与真核生物PIWI有共同起源的PIWI蛋白 (HrAgo1).
- HrAgo1调解RNA引导的RNA分裂,并促进基因沉默,与已知的原生动物阿尔戈纳特不同,这些原生动物通常使用DNA.
- 低温EM和单分子数据显示,HrAgo1具有混合的结构和功能特征,结合了真核细胞AGO和PIWI蛋白的特征.
结论:
- 深度分支的考古PIWI蛋白HrAgo1表现出RNA引导的RNA分裂活动,这表明它在RNA沉默中起到了早期的作用.
- HrAgo1的分子架构似乎代表了一个祖先状态,早于真核生物AGO和PIWI蛋白的功能分歧.
- 这一发现揭示了RNA沉默路径的起源和早期进化,这些路径在导致真核细胞的血统中存在.
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