哺乳动物和鸟类核基因组中线型编码DNA的不同进化轨迹
Yu-Chi Chen1,2, David L J Vendrami3,4,5,6, Maximilian L Huber2
1Computational Systems Biology, Faculty of Biochemical and Chemical Engineering, TU Dortmund University, 44227 Dortmund, Germany.
Genome research
|March 31, 2025
概括
带有完整基因的线粒体起源核DNA (NUMT) 在鸟类和哺乳动物中普遍存在. 证据表明这些NUMT的长期选择和潜在功能,挑战了关于它们进化命运的先前假设.
科学领域:
- 基因组学就是基因组学.
- 进化生物学 进化生物学
- 分子生物学分子生物学
背景情况:
- 来自有机体基因组的遗传物质,如线粒体,可以整合到核基因组中,形成线粒体起源的核DNA (NUMTs).
- 对于这些NUMT集成的进化维护机制,特别是保留功能基因的那些,仍然不太了解.
- 线粒体起源的核基因 (线粒体编码核基因) 持续存在的两个主要假设包括最近的物种间基因流 (内进) 和持续的自然选择.
研究的目的:
- 调查线粒体起源核DNA (NUMT) 的流行率和进化机制,这些核DNA在各种物种中含有完整的线粒体基因.
- 测试最近内向与长期选择在功能性NUMT的维护中的假设.
- 探索NUMT插入的潜在功能意义和进化动态.
主要方法:
- 对1000多种鸟类和哺乳动物的全基因组扫描,以识别线粒体起源的核DNA (NUMTs).
- 对比基因组分析以评估跨物种NUMT的序列相似性和分歧.
- 遗传学和进化分析以检测NUMT基因内的选择特征,包括适应性进化.
主要成果:
- 在哺乳动物和鸟类中发现了具有完整的线粒体基因的线粒体起源 (NUMT) 的分离核DNA的一个广泛的子类.
- 其中一些NUMT表现出跨物种的相似性,表明保存的进化过程.
- 许多线粒体编码NUMT显示了长期选择的证据,其中一个子集显示了与适应性进化一致的信号,例如在七种猿类中发现的人类NUMT.
结论:
- 线粒体起源的核DNA (NUMT) 含有完整的,潜在的功能性线粒体基因,在脊椎动物中比以前认为的更为常见.
- 长期选择,而不是仅仅是最近的内进,似乎在某些NUMT的进化维护中发挥了重要作用.
- 这些发现表明,NUMT插入偶尔可以是功能性的,并受到适应性的进化压力.
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