Palazzo Antonio, Caizzi Ruggiero, Viggiano Luigi, Marsano René Massimiliano
Department of Biology, University of Bari "Aldo Moro," Italy.
Genome Biol Evol. 2017 Jun 1;9(6):1637-1645. doi: 10.1093/gbe/evx122.
The contribution of the transposons' promoter in the horizontal transfer process is quite overlooked in the scientific literature. To shed light on this aspect we have mimicked the horizontal transfer process in laboratory and assayed in a wide range of hosts (fly, human, yeast and bacteria) the promoter activity of the 5' terminal sequences in Bari1 and Bari3, two Drosophila transposons belonging to the Tc1-mariner superfamily. These sequences are able to drive the transcription of a reporter gene even in distantly related organisms at least at the episomal level. By combining bioinformatics and experimental approaches, we define two distinct promoter sequences for each terminal sequence analyzed, which allow transcriptional activity in prokaryotes and eukaryotes, respectively. We propose that the Bari family of transposons, and possibly other members of the Tc1-mariner superfamily, might have evolved "blurry promoters," which have facilitated their diffusion in many living organisms through horizontal transfer.
转座子启动子在水平转移过程中的作用在科学文献中相当被忽视。为了阐明这一方面，我们在实验室中模拟了水平转移过程，并在广泛的宿主（果蝇、人类、酵母和细菌）中检测了属于Tc1-水手超家族的两个果蝇转座子Bari1和Bari3的5'末端序列的启动子活性。这些序列即使在远缘相关的生物体中至少在游离体水平上也能够驱动报告基因的转录。通过结合生物信息学和实验方法，我们为每个分析的末端序列定义了两个不同的启动子序列，分别允许在原核生物和真核生物中进行转录活性。我们提出，Bari转座子家族，以及可能的Tc1-水手超家族的其他成员，可能已经进化出了“模糊启动子”，这通过水平转移促进了它们在许多生物体中的扩散。
