小事在哪里:一项泛真核的调查表明,中性过程可能解释了小的内核进化中的大部分
Graham E Larue1, Scott W Roy2,3
1Quantitative and Systems Biology Graduate Program, University of California Merced, Merced, CA 95343, USA.
Nucleic acids research
|October 11, 2023
概括
通过小结合体处理的小内子已经存在了15亿年. 它们的进化似乎是由中性过程驱动的,而不是功能或有害的压力,挑战了以前的假设.
科学领域:
- 遗传学 遗传学 是一个
- 进化生物学 进化生物学
- 分子生物学分子生物学
背景情况:
- 结合体内核对于真核生物中的RNA处理至关重要.
- 一个小的spliceosome处理一个小部分的内子,但在进化过程中一直存在.
- 了解小内核进化是理解真核生物基因组动态的关键.
研究的目的:
- 为了研究微型内子在真核生物中的进化历史和分布.
- 确定轻微拼接长期存在的驱动力.
- 为了提供一个全面的概述小的内部进化.
主要方法:
- 在3000多个真核生物基因组中识别小内子.
- 对内部分布和进化模式的比较基因组分析.
- 统计分析以对比进化模型和基因年龄偏差.
主要成果:
- 较小的内部体表现出多样化的进化轨迹,包括一些真菌和藻类的高流行率,以及损失的情况.
- 据估计,祖先的小内部密度与脊椎动物相似,表明长期静止.
- 小和大内突进化表现出类似的模式,主要由基因年龄而不是功能性或有害的选择来解释.
结论:
- 中性进化过程显著影响小内突动力学.
- 含有内基因的小基因的功能偏差可以归因于基因年龄.
- 轻微拼接的持续性并不能通过普遍的调节作用来解释,这表明了谱系特定的功能.
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