在Cryptococcus neoformans中失去RNA干扰后,不同的进化轨迹
Jun Huang1, Connor J Larmore1, Shelby J Priest1
1Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC 27710, USA.
bioRxiv : the preprint server for biology
|August 26, 2024
概括
在Cryptococcus neoformans中RNAi损失可能导致超突变和快速适应,通常涉及转子子活动. 这项研究揭示了RNAi损失后的独特进化路径,有或没有超变异.
科学领域:
- 微生物学 微生物学
- 遗传学 遗传学 是一个
- 进化生物学 进化生物学
背景情况:
- 微生物的高突变可能是适应性的,与多细胞生物不同.
- 之前的研究已经在*Cryptococcus neoformans*中发现了具有Cnl1逆转移素活性的超变异体,与影响RNAi的Znf3突变有关.
- 在微生物适应中RNAi损失的作用需要进一步阐明.
研究的目的:
- 为了识别和描述C. neoformans*中的RNAi功能丧失突变.
- 为了研究RNAi损失,转子子积累和超变异之间的联系.
- 探索RNAi缺陷在C. neoformans*中的进化后果.
主要方法:
- 开发两条生物信息管道,以检测387个*C. neoformans*分离物中的RNAi功能丧失突变.
- 将已识别的RNAi功能丧失突变引入非超突变菌株.
- *在体外*传递RNAi损失菌株和遗传交叉.
主要成果:
- 确定了几种具有RNAi功能丧失突变的*C.neoformans*分离物,但它们不是超级突变物.
- 这些突变的实验引入导致了高转子子负荷的菌株的超变异.
- 过渡实验显示,C. deneoformans*具有增强的转子子负荷的超变异,而来自交叉的F1后代由于Cnl1和KDZ1转子插入而表现出超变异.
结论:
- 在C. neoformans中,RNAi损失相对普遍 (~1.8%),为不同的进化轨迹提供了基础.
- RNAi损失可以通过转子子积累实现超变异或允许在不增加突变率的情况下生存.
- 这项研究强调了RNAi缺乏在微生物进化中的适应潜力.
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