继宿主后的基因组进化在爱尔兰马饥荒病原体血统中跳跃
Sylvain Raffaele1, Rhys A Farrer, Liliana M Cano
1The Sainsbury Laboratory, Norwich Research Park, Norwich NR4 7UH, UK.
概括
宿主跳跃在植物病原体中,如Phytophthora infestans驱动着快速的基因组进化. 富含重复的区域和表观遗传基因加速了适应,揭示了病原体进化的关键机制.
科学领域:
- 基因组学就是基因组学.
- 进化生物学 进化生物学
- 植物病理学 植物病理学
背景情况:
- 植物病原体经常通过宿主跳跃进化,导致专业化.
- 宿主跳跃对诸如Phytophthora infestans之类的病原体基因组进化的影响尚不清楚.
研究的目的:
- 在宿主跳跃后的Phytophthora infestans血统中调查序列变异和基因组进化的模式.
- 确定与加速进化和宿主适应相关的基因组区域和基因.
主要方法:
- 从P. infestans血统中的四个姐妹物种重新测序了六个基因组.
- 对序列变异,结构多态性和跨基因组的积极选择的分析.
- 在重复丰富和基因稀疏区域中识别基因,包括在植物中诱导和参与表观遗传过程的基因.
主要成果:
- 在基因组中观察到不均的进化速率,在重复丰富的区域中出现更高的速率.
- 复制丰富区域的基因显示结构多态度增加和积极选择,特别是植物中诱导的基因.
- 参与表观遗传过程的基因被确定为在基因稀疏区域快速演变的基因.
结论:
- 动态的,重复丰富的基因组区块在宿主跳跃后加速基因进化中起着至关重要的作用 P. infestans.
- 主体适应似乎是这种病原体血统中基因组进化的重要驱动因素.
- 表观遗传基因代表了另一类快速进化的元素,有助于病原体的适应.
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