Pianezza Riccardo, Scarpa Almorò, Haider Anna, Signor Sarah, Kofler Robert
Institut für Populationsgenetik, Vetmeduni Vienna, Veterinärplatz 1, Vienna 1210, Austria.
Vienna Graduate School of Population Genetics, Vetmeduni Vienna, Vienna, Austria.
Mol Biol Evol. 2025 Jul 1;42(7). doi: 10.1093/molbev/msaf143.
Transposable elements (TEs) are repetitive sequences capable of mobilizing within genomes, exerting a significant influence on evolution throughout the tree of life. Using a novel approach that does not require prior knowledge of the sequence of repeats, we identified three novel TE invasions in Drosophila melanogaster: McLE spread between 1990-2000, Souslik between 2009-2012, and Transib1 between 2013-2016. We recapitulate previous findings, revealing that a total of 11 TEs invaded D. melanogaster over the past two centuries. These 11 invasions increased the fly genome by ∼1 Mbp. Using data from over 1,400 arthropod genomes, we provide evidence that these TE invasions were triggered by horizontal transfers, with Drosophila simulans and species of the Drosophila willistoni group acting as putative donors. Through the analysis of ∼600 short-read datasets spanning diverse geographic regions, we reveal the rapidity of TE invasions: Transib1 swiftly multiplied from three isolated epicenters in 2014 to all investigated populations in just 2 years. Our findings suggest that anthropogenic activities, which facilitate the range and population expansions of D. melanogaster, could have accelerated the rate of horizontal transposon transfer as well as the spread of the TEs into the worldwide population. Given the significant impact of TEs on evolution and the potential involvement of humans in their dispersal, our research has crucial implications for both evolution and ecology.
转座元件（TEs）是能够在基因组内移动的重复序列，对整个生命之树的进化产生重大影响。我们采用了一种无需重复序列先验知识的新方法，在黑腹果蝇中鉴定出三次新的TE入侵事件：McLE在1990年至2000年间扩散，Souslik在2009年至2012年间扩散，Transib1在2013年至2016年间扩散。我们重现了先前的研究结果，发现在过去两个世纪中，共有11种TE入侵了黑腹果蝇。这11次入侵使果蝇基因组增加了约1兆碱基对。利用来自1400多个节肢动物基因组的数据，我们提供证据表明这些TE入侵是由水平转移引发的，拟暗果蝇和威氏果蝇组的物种可能是供体。通过对跨越不同地理区域的约600个短读数据集的分析，我们揭示了TE入侵的速度：Transib1在2014年从三个孤立的中心迅速繁殖，仅在两年内就扩散到所有调查的种群中。我们的研究结果表明，促进黑腹果蝇范围和种群扩张的人为活动可能加速了转座子水平转移的速度以及TEs向全球种群的传播。鉴于TEs对进化的重大影响以及人类可能参与其传播，我们的研究对进化和生态学都具有至关重要的意义。
