通过改变分子进化的动态性来加速适应性
Michael J McDonald1,2, Daniel P Rice1,2, Michael M Desai1,2,3
1Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, Massachusetts 02138, USA.
Nature
|February 25, 2016
概括
性繁殖和重组通过提高自然选择的效率来加速适应. 这一过程有助于更快地修复有益的突变,并防止有害的突变积累,与无性种群不同.
科学领域:
- 进化生物学
- 种群遗传学
背景情况:
- 性和重组是广泛的,尽管他们的成本,对进化理解构成挑战.
- 一个关键的假设是, 通过像"费舍尔-穆勒效应"和"垃圾中的红宝石"这样的机制,
研究的目的:
- 为了比较性和无性酵母种群的序列级适应动态.
- 通过性别加速适应的特定基因组机制.
主要方法:
- 使用Saccharomyces cerevisiae (酵母) 的实验进化.
- 在性和无性种群之间的序列级别适应的分子特征的比较分析.
主要成果:
- 性改变了固定突变的频谱, 减轻了理论预测的克隆干扰.
- 在无性种群中,有害突变会被固定,但在性种群中被重组阻止.
结论:
- 通过增强自然选择分离有益与有害突变的能力,
- 重组对于在适应过程中防止有害突变的固定至关重要.
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