一个神秘色彩的基因复合体进化中的大规模突变
Romain Villoutreix1,2, Clarissa F de Carvalho1, Víctor Soria-Carrasco1
1Department of Animal and Plant Sciences, University of Sheffield, Sheffield S10 2TN, UK.
Science (New York, N.Y.)
|July 25, 2020
概括
结构性突变,如大缺失,可以通过包装有益的基因复合体来驱动适应. 这项研究揭示了这些"超级突变"是如何产生独特的昆虫颜色变异的, 挑战了以前的超级基因理论.
科学领域:
- 进化生物学
- 遗传学
- 分子进化
背景情况:
- 了解野生种群适应的遗传基础至关重要.
- 重组抑制和新突变在塑造适应性特征中的作用仍在争论中.
- 人们越来越认识到结构突变及其对适应的影响.
研究的目的:
- 为了研究底层的遗传结构神秘的颜色变形在*Timema chumash*棒虫.
- 确定驱动这些形态的进化机制 (重组抑制与大规模突变).
- 评估平衡选择和内进的相对贡献,以维持这些适应变异.
主要方法:
- 与颜色变异相关的遗传位置的分析.
- 进行比较基因组学以确定抑制的重组和大规模突变的区域.
- 人口遗传分析以推断选择和基因流动的作用.
主要成果:
- 多个相互关联的位置, 而不是单一的超基因,
- 在七种*Timema*物种的绿色形态中发现了大基量删除 ("超级突变").
- 在维持这些突变方面,平衡选择似乎比内进更强大.
结论:
- 大规模的突变,如删除,可以有效地包装基因复合体,促进适应.
- 抑制的重组 (超基因) 和大突变都会导致像形态体这样的离散适应单元的形成.
- 这项研究强调了生物多样性产生和维持的各种进化途径.
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