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性染色体异态化和快速X效应在类动物中
Iulia Darolti1,2, Lydia J M Fong1, Benjamin A Sandkam3
1Department of Zoology and Biodiversity Research Centre, University of British Columbia, Vancouver, British Columbia, Canada.
Molecular ecology
|June 13, 2023
概括
半双相性驱动鱼类性染色体进化中的快速X效应. 这发生在性别染色体分化早期,在具有更大的男性半双性质的物种中观察到更高的X链基因分歧.
科学领域:
- 进化遗传学的进化遗传学
- 进行比较的基因组学.
- 性染色体的进化性染色体的进化
背景情况:
- 快速X效应,以加速X染色体进化为特征,在各种异形性染色体中观察到.
- 在性染色体分化过程中,快速X效应的检测时间尚不清楚.
- 波西里鱼在性染色体异构中表现出极端的变异,为研究X染色体进化提供了一个模型.
研究的目的:
- 为了研究X染色体进化在poeciliid鱼作为一个函数的半双相性.
- 为了确定这个群体中Fast-X效应的原因.
- 为了确定性染色体起源的进化时间,在poeciliid clade.
主要方法:
- 在多种鱼类鱼类中对序列分歧和多态度数据的比较分析.
- 对X染色体相对于自体基因的演变进行评估.
- 评估X染色体异构和男性半双性水平.
主要成果:
- 在具有高雄半双体性 (P. picta,P. parae) 的物种中检测到更高的X链接基因分歧率 (快速X效应).
- 在P. reticulata中没有观察到X链接基因进化速率的显著变化,P. reticulata具有同型性染色体和低半双相性.
- 具有中间性染色体差异化的P. wingei在较旧的分歧层上显示出非同义替代的增加率.
结论:
- 半双相性在性染色体进化过程中推动快速X效应起着至关重要的作用.
- 快速X效应在性别染色体分化早期变得可检测,与Y染色体退化程度和男性半双相相关.
- 对比基因组方法对于研究性染色体进化和起源是有效的.
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