Biémont Christian, Nardon Christiane, Deceliere Grégory, Lepetit David, Loevenbruck Catherine, Vieira Cristina
Laboratoire de Biométrie et Biologie Evolutive, UMR Centre National de la Recherche Scientifique 5558, Université Lyon 1, 69622 Villeurbanne Cedex, France.
Evolution. 2003 Jan;57(1):159-67. doi: 10.1111/j.0014-3820.2003.tb00225.x.
Transposable elements (TEs), which promote various kinds of mutations, constitute a large fraction of the genome. How they invade natural populations and species is therefore of fundamental importance for understanding the dynamics of genetic diversity and genome composition. On the basis of 85 samples of natural populations of Drosophila simulans, we report the distributions of the genome insertion site numbers of nine TEs that were chosen because they have a low average number of sites. Most populations were found to have 0-3 insertion sites, but some of them had a significantly higher number of sites for a given TE. The populations located in regions outside Africa had the highest number of sites for all elements except HMS Beagle and Coral, suggesting a recent increase in the activity of some TEs associated with the colonization patterns of Drosophila simulans. The element Tirant had a very distinctive pattern of distribution: it was identified mainly in populations from East Africa and some islands in the Indian Ocean, and its insertion site number was low in all these populations. The data suggest that the genome of the entire species of Drosophila simulans may be being invaded by TEs from populations in which they are present in high copy number.
转座元件（TEs）可引发各种突变，在基因组中占很大比例。因此，它们如何侵入自然种群和物种对于理解遗传多样性和基因组组成的动态变化至关重要。基于85个拟暗果蝇自然种群的样本，我们报告了9种TEs的基因组插入位点数量分布情况，这些TEs因平均位点数量较低而被选中。大多数种群被发现有0至3个插入位点，但其中一些种群对于特定的TEs具有显著更多的位点。位于非洲以外地区的种群对于除HMS Beagle和Coral之外的所有元件都有最高的位点数量，这表明与拟暗果蝇的定殖模式相关的一些TEs的活性近期有所增加。元件Tirant具有非常独特的分布模式：它主要在东非和印度洋一些岛屿的种群中被鉴定出来，并且在所有这些种群中其插入位点数量都很低。数据表明，拟暗果蝇整个物种的基因组可能正受到来自那些TEs高拷贝数种群的TEs的侵入。
