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在Amoebozoa中微RNA的演变以及多细胞性起源的含义
Bart Edelbroek1, Jonas Kjellin1, Inna Biryukova2
1Department of Cell and Molecular Biology, Uppsala Biomedical Centre, Uppsala University, 75124 Uppsala, Sweden.
Nucleic acids research
|February 20, 2024
概括
微RNA (miRNA) 存在于多种类型的虫中,这表明它们的起源很古老. 它们的快速进化和在多细胞发育中不重要的作用挑战了以前的假设.
科学领域:
- 进化生物学是进化的生物学.
- 分子生物学分子生物学
- 基因组学就是基因组学.
背景情况:
- 微RNA (miRNA) 是植物和动物的关键基因调节者,可能影响多细胞性.
- 之前的研究在有限的单细胞真核生物中确定了miRNA,使其在其他血统中的进化历史未被探索.
研究的目的:
- 为了调查miRNA在各种Amoebozoa物种中的存在和进化模式.
- 评估miRNAs在从单细胞生命过渡到多细胞生命中的作用.
主要方法:
- 来自Acanthamoeba,Physarum和dictyostelids的小RNA测序数据的生物信息分析.
- 比较基因组学以确定跨物种的保存和独特的miRNAs.
- 在Dictyostelium discoideum中对miRNA缺乏突变的表型分析.
主要成果:
- 在所有检查的虫中,确定了符合植物和动物标准的miRNA,使已知的miRNA载原体从7个增加到15个.
- 在Amoebozoa中观察到miRNAs的快速增加和/或损失,每种物种大多具有独特的miRNAs.
- 证明Dictyostelium discoideum突变体中的miRNA损失不会阻碍多细胞发育.
结论:
- 微RNA在阿米博动物中广泛存在,这表明它们具有古老的进化起源.
- 在Amoebozoa中miRNAs的快速周转表明了高的进化可塑性.
- 在这些生物体中,miRNAs的存在并不是多细胞性进化的严格前提.
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