Effects of inversions on within- and between-species recombination and divergence.
Effects of inversions on within- and between-species recombination and divergence.
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DOI：
10.1093/gbe/evr081
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发表时间：
2011
影响因子：
3.3
通讯作者：
Noor MA
中科院分区：
文献类型：
--
作者：
Stevison LS;Hoehn KB;Noor MA
染色体倒位通过减少倒位区域内的交换和增加基因组中其他地方的交换来破坏杂合子中的重组。反向区域重组的减少有利于杂交物种的维持，正如染色体物种形成的各种模型所概述的。我们提出了一个全面的比较反转重组率和核苷酸分歧的影响。在一个倒置区分果蝇pseudobscura和果蝇persimilis，我们检测到一个双重组9,739后代F1杂交筛选，与公布的物种内观察到的双交叉频率一致。尽管物种内和物种间的交换率相似，但我们没有发现基于序列的证据表明在这种倒置中物种间正在进行基因交换，但推断物种内存在显著的交换。我们还观察到更大的分化，在地区之间的物种与物种内的反转断点附近。此外，我们观察到强烈的“染色体间效应”（更高的重组倒位杂合子物种之间）与高达9倍的重组率高沿着共线段的染色体2的杂交。此外，我们观察到，最易受重组率变化影响的区域对应于同源核型中重组率较低的区域。最后，我们发现，种间核苷酸的分歧是较低的重组率增加较大的地区，可能导致更大的种间交换。总的来说，我们已经确定了几个相似之处和不同的反转分离内与物种之间的重组和分歧的影响。我们的结论是，这些差异最有可能是由于较低的频率的异核型和健身的后果，从积累的各种物种之间的不相容性。此外，我们已经确定了以前没有考虑过的物种间基因交换的倒位的可能影响。
Chromosomal inversions disrupt recombination in heterozygotes by both reducing crossing-over within inverted regions and increasing it elsewhere in the genome. The reduction of recombination in inverted regions facilitates the maintenance of hybridizing species, as outlined by various models of chromosomal speciation. We present a comprehensive comparison of the effects of inversions on recombination rates and on nucleotide divergence. Within an inversion differentiating Drosophila pseudoobscura and Drosophila persimilis, we detected one double recombinant among 9,739 progeny from F1 hybrids screened, consistent with published double-crossover frequencies observed within species. Despite similar rates of exchange within and between species, we found no sequence-based evidence of ongoing gene exchange between species within this inversion, but significant exchange was inferred within species. We also observed greater differentiation at regions near inversion breakpoints between species versus within species. Moreover, we observed strong “interchromosomal effect” (higher recombination in inversion heterozygotes between species) with up to 9-fold higher recombination rates along collinear segments of chromosome two in hybrids. Further, we observed that regions most susceptible to changes in recombination rates corresponded to regions with lower recombination rates in homokaryotypes. Finally, we showed that interspecies nucleotide divergence is lower in regions with greater increases in recombination rate, potentially resulting from greater interspecies exchange. Overall, we have identified several similarities and differences between inversions segregating within versus between species in their effects on recombination and divergence. We conclude that these differences are most likely due to lower frequency of heterokaryotypes and to fitness consequences from the accumulation of various incompatibilities between species. Additionally, we have identified possible effects of inversions on interspecies gene exchange that had not been considered previously.
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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
DOI：
10.1101/sqb.2003.68.69
发表时间：
2003-01-01
期刊：
COLD SPRING HARBOR SYMPOSIA ON QUANTITATIVE BIOLOGY
影响因子：
--
作者：
Fan, JB;Oliphant, A;Chee, MS
通讯作者：
Chee, MS
影响因子：
3.3
作者：
Carneiro, Miguel;Blanco-Aguiar, Jose A.;Nachman, Michael W.
通讯作者：
Nachman, Michael W.
DOI：
10.1073/pnas.88.1.305
发表时间：
1991-01-01
影响因子：
11.1
作者：
AQUADRO, CF;WEAVER, AL;ANDERSON, WW
通讯作者：
ANDERSON, WW
影响因子：
3.9
作者：
de Proce, Sophie Marion;Halligan, Daniel L.;Charlesworth, Brian
通讯作者：
Charlesworth, Brian