Ranz José María, González Josefa, Casals Ferran, Ruiz Alfredo
Department de Genètica i de Microbiologia, Facultat de Ciències, Edifici C, Universitat Autònoma de Barcelona, 08193 Bellaterra, Barcelona, Spain.
Evolution. 2003 Jun;57(6):1325-35. doi: 10.1111/j.0014-3820.2003.tb00340.x.
The role played by gene transpositions during the evolution of eukaryotic genomes is still poorly understood and indeed has been analyzed in detail only in nematodes. In Drosophila, a limited number of transpositions have been detected by comparing the chromosomal location of genes between different species. The relative importance of gene transposition versus other types of chromosomal rearrangements, for example, inversions, has not yet been evaluated. Here, we use physical mapping to perform an extensive search for long-distance gene transpositions and assess their impact during the evolution of the Drosophila genome. We compare the relative order of 297 molecular markers that cover 60% of the euchromatic fraction of the genome between two related Drosophila species and conclude that the frequency of gene transpositions is very low, namely one order of magnitude lower than that of nematodes. In addition, gene transpositions seem to be events almost exclusively associated with genes of repetitive nature such as the Histone gene complex (HIS-C).
基因转座在真核生物基因组进化过程中所起的作用仍未得到充分理解，实际上仅在线虫中得到了详细分析。在果蝇中，通过比较不同物种间基因的染色体定位，检测到了有限数量的转座。基因转座相对于其他类型的染色体重排（例如倒位）的相对重要性尚未得到评估。在此，我们利用物理图谱对远距离基因转座进行广泛搜索，并评估它们在果蝇基因组进化过程中的影响。我们比较了覆盖两个相关果蝇物种基因组常染色质部分60%的297个分子标记的相对顺序，得出基因转座频率非常低的结论，即比线虫低一个数量级。此外，基因转座似乎几乎完全是与具有重复性质的基因（如组蛋白基因复合体（HIS-C））相关的事件。
