The relation between recombination rate and patterns of molecular evolution and variation in Drosophila melanogaster.
The relation between recombination rate and patterns of molecular evolution and variation in Drosophila melanogaster.
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DOI：
10.1093/molbev/msu056
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发表时间：
2014-04
影响因子：
10.7
通讯作者：
Charlesworth B
中科院分区：
文献类型：
--
作者：
Campos JL;Halligan DL;Haddrill PR;Charlesworth B
与有性繁殖相关的基因重组通过减少希尔-罗伯逊干扰的强度提高了自然选择的效率。这种干扰可能是通过选择性地扫描阳性选择的等位基因或通过针对有害突变的背景选择(BGS)引起的。它的后果可以通过比较具有不同交叉率的基因组区域的分子进化和变异模式来研究。我们对重组在黑腹果蝇中的益处进行了全面的研究，方法是对比五个独立的基因组区域，这些区域不能与基因组的其他部分交叉，并比较不同交叉率的区域，使用地理上接近该物种祖先种群的非洲种群的DNA序列多态数据，以及与相关物种的序列差异。我们观察到非交叉(NC)区域的序列多样性降低，这与在没有重组的情况下硬选择性扫描的效果不一致。总体而言，观察到的模式表明，基因经历的重组率与正向选择和纯化选择效率的提高呈正相关。结果与BGS模型一致，该模型考虑了NC区域中选定位置之间的干扰，以及BGS、选择性扫描和过去的种群扩张对经历交叉的基因组区域的可变性的联合影响。在这些交叉区，X染色体表现出比常染色体更高的适应性蛋白质序列进化速度，这意味着更快的-X效应。
Genetic recombination associated with sexual reproduction increases the efficiency of natural selection by reducing the strength of Hill–Robertson interference. Such interference can be caused either by selective sweeps of positively selected alleles or by background selection (BGS) against deleterious mutations. Its consequences can be studied by comparing patterns of molecular evolution and variation in genomic regions with different rates of crossing over. We carried out a comprehensive study of the benefits of recombination in Drosophila melanogaster, both by contrasting five independent genomic regions that lack crossing over with the rest of the genome and by comparing regions with different rates of crossing over, using data on DNA sequence polymorphisms from an African population that is geographically close to the putatively ancestral population for the species, and on sequence divergence from a related species. We observed reductions in sequence diversity in noncrossover (NC) regions that are inconsistent with the effects of hard selective sweeps in the absence of recombination. Overall, the observed patterns suggest that the recombination rate experienced by a gene is positively related to an increase in the efficiency of both positive and purifying selection. The results are consistent with a BGS model with interference among selected sites in NC regions, and joint effects of BGS, selective sweeps, and a past population expansion on variability in regions of the genome that experience crossing over. In such crossover regions, the X chromosome exhibits a higher rate of adaptive protein sequence evolution than the autosomes, implying a Faster-X effect.
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影响因子：
64.8
作者：
Clark, Andrew G.;Eisen, Michael B.;MacCallum, Iain
通讯作者：
MacCallum, Iain
影响因子：
10.7
作者：
Arguello, J. Roman;Zhang, Yue;Long, Manyuan
通讯作者：
Long, Manyuan
影响因子：
4.5
作者：
Corbett-Detig, Russell B.;Hartl, Daniel L.
通讯作者：
Hartl, Daniel L.
使用下一代 DNA 测序数据进行变异发现和基因分型的框架。
影响因子：
30.8
作者：
通讯作者：
--
影响因子：
4.5
作者：
Comeron JM;Ratnappan R;Bailin S
通讯作者：
Bailin S