Reduced efficacy of selection in regions of the Drosophila genome that lack crossing over.
Reduced efficacy of selection in regions of the Drosophila genome that lack crossing over.
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DOI：
10.1186/gb-2007-8-2-r18
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发表时间：
2007
期刊：
影响因子：
12.3
通讯作者：
Charlesworth B
中科院分区：
文献类型：
--
作者：
Haddrill PR;Halligan DL;Tomaras D;Charlesworth B
对黑腹果蝇（Drosophila melanogaster）和雅库巴果蝇（Drosophila yakuba）进行的全基因组比较观察结果表明，在没有交换的情况下，选择的效力严重降低，导致这些区域有害突变的积累。重组环境的预测影响模式的蛋白质序列的进化，通过影响的Hill-Robertson干扰之间的链接网站进行选择。在基因组的自由重组区域中，选择应该比在基因重组率低的区域中更有效地结合新的有益突变，并消除有害突变。我们通过对黑腹果蝇（Drosophila melanogaster）和果蝇（D.日本料理。在没有交叉的基因组区域，我们发现在非同义位点和长内含子中的分歧升高，密码子使用偏好的虚拟缺失，以及基因长度的增加。然而，我们几乎没有发现证据表明，高，中，低交叉频率的区域之间的进化模式的差异。此外，第四条染色体上的基因与第四条染色体以外的其他无交叉基因相比，表现出更极端的偏离。观察到的所有模式都与在没有交换的情况下选择效力的严重降低一致，导致这些区域中有害突变的积累。我们的研究结果还表明，即使是非常低的交换频率也足以维持选择的效力。
Observations from a genome-wide comparison of Drosophila melanogaster and Drosophila yakuba are consistent with a severe reduction in the efficacy of selection in the absence of crossing over, resulting in the accumulation of deleterious mutations in these regions. The recombinational environment is predicted to influence patterns of protein sequence evolution through the effects of Hill-Robertson interference among linked sites subject to selection. In freely recombining regions of the genome, selection should more effectively incorporate new beneficial mutations, and eliminate deleterious ones, than in regions with low rates of genetic recombination. We examined the effects of recombinational environment on patterns of evolution using a genome-wide comparison of Drosophila melanogaster and D. yakuba. In regions of the genome with no crossing over, we find elevated divergence at nonsynonymous sites and in long introns, a virtual absence of codon usage bias, and an increase in gene length. However, we find little evidence for differences in patterns of evolution between regions with high, intermediate, and low crossover frequencies. In addition, genes on the fourth chromosome exhibit more extreme deviations from regions with crossing over than do other, no crossover genes outside the fourth chromosome. All of the patterns observed are consistent with a severe reduction in the efficacy of selection in the absence of crossing over, resulting in the accumulation of deleterious mutations in these regions. Our results also suggest that even a very low frequency of crossing over may be enough to maintain the efficacy of selection.
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影响因子：
2
作者：
Kondrashov, Fyodor A.;Ogurtsov, Aleksey Y.;Kondrashov, Alexey S.
通讯作者：
Kondrashov, Alexey S.
DOI：
10.1017/s0016672302006067
发表时间：
2003-04-01
期刊：
GENETICAL RESEARCH
影响因子：
--
作者：
Kliman, RM;Hey, J
通讯作者：
Hey, J
影响因子：
1.5
作者：
Charlesworth, B
通讯作者：
Charlesworth, B
影响因子：
10.7
作者：
Bierne, N;Eyre-Walker, A
通讯作者：
Eyre-Walker, A
影响因子：
7
作者：
Bray, N;Pachter, L
通讯作者：
Pachter, L