适应性辐射的基因组基板在非洲鱼鱼的基因组基板
David Brawand1,2, Catherine E Wagner3,4, Yang I Li2
1Broad Institute of MIT and Harvard, Cambridge, Massachusetts 02142, USA.
Nature
|September 5, 2014
概括
非洲鱼基因组揭示了快速进化和基因重复驱动适应性辐射. 这些分子机制,包括新型的microRNA和转子子插入,促进了东非类动物的快速多样化.
科学领域:
- 进化生物学 进化生物学
- 基因组学就是基因组学.
- 分子生物学分子生物学
背景情况:
- 东非大湖中的鱼表现出了显著的适应性辐射,展示了显著的表型多样性.
- 了解这种多样性的分子基础对于进化研究至关重要.
研究的目的:
- 调查类表型多样性的基因组和转录基因组基础.
- 为了比较不同非洲鱼系的分子进化,包括祖先和快速多样化的物种.
主要方法:
- 五个非洲鱼系的基因组和转录组测序:尼罗河鱼,Neolamprologus brichardi/pulcher,Metriaclima斑马,Pundamilia nyererei,和Astatotilapia burtoni. 这五个非洲鱼系的基因组和转录组测序.
- 对基因重复,非编码元素分歧,编码序列演变和可转换元素活动的分析.
- 在6个密切相关的维多利亚湖物种中的60个个体上进行了全基因组关联研究.
主要成果:
- 与尼罗河鱼相比,在东非鱼系中观察到过多的基因重复和丰富的非编码元素分歧.
- 确定了加快编码序列演变,与可转移元素插入相关的表达分歧,以及新型微RNAs的调节.
- 在维多利亚湖鱼中检测到包括古代多态性在内的编码和调节变体的全基因组多样化选择.
结论:
- 多种分子机制,包括基因重复和调控变化,已经塑造了东非鱼基因组.
- 在放松的净化选择过程中,静止基因变异的积累可能促进了类动物随后的进化多样化.
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