在Cyberlindnera酵母中rDNA基因的多态性表明出生和死亡进化事件的发生
Rodolfo Bizarria1,2, Tatiane de Castro Pietrobon1,2, Henrique Ferreira1
1Department of General and Applied Biology, São Paulo State University (UNESP), Rio Claro, SP 13.506-900, Brazil.
FEMS yeast research
|June 8, 2023
概括
一种新的酵母物种中的核糖体DNA (rDNA) 显示出高度的多样性,挑战了协同进化的想法. 这表明了这些重要的基因的替代进化模型,如出生和死亡.
科学领域:
- 微生物学 微生物学
- 分子进化分子进化
- 遗传学 遗传学 是一个
背景情况:
- 单核核核糖核糖核糖核糖核糖核糖核酸 (rRNA) 基因存在于串联阵列中,并且通常通过协同进化同质化,形成物种条形码.
- 在rDNA中观察到高异质性,特别是在Saccharomycotina酵母中,质疑协同进化的普遍性.
研究的目的:
- 在与Cyberlindnera相关的新酵母物种中研究26SrRNA D1/D2域和基因间转录间隔器的多态性和异质性.
- 探索驱动这种酵母物种rDNA多样性的进化机制.
主要方法:
- 克隆核糖体DNA (rDNA) 序列的遗传学网络分析.
- 预测rRNA二次结构的分析.
主要成果:
- 研究的rDNA区域 (26S rRNA D1/D2和ITS) 没有均质化,这与协调进化模型相矛盾.
- 遗传学网络分析揭示了网状细胞的进化,而不是简单的分叉树.
- 预测的rRNA二次结构显示出显著的差异,保留了针头环.
结论:
- 这种新的酵母物种中的rDNA是通过网联和潜在的出生和死亡而进化的,而不是协同进化的.
- 这些发现表明,一些rDNA单元可能不活跃,导致非同质化的进化.
- 这项研究促使进一步研究酵母菌中rDNA基因的多样化进化路径.
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