Institute for Evolution and Biodiversity (IEB), University of Münster, Münster, Germany.
Institute of Experimental Pathology, University of Münster, Münster, Germany.
Mol Ecol. 2019 Mar;28(6):1537-1549. doi: 10.1111/mec.14794. Epub 2018 Aug 4.
The growing knowledge about the influence of transposable elements (TEs) on (a) long-term genome and transcriptome evolution; (b) genomic, transcriptomic and epigenetic variation within populations; and (c) patterns of somatic genetic differences in individuals continues to spur the interest of evolutionary biologists in the role of TEs in adaptive evolution. As TEs can trigger a broad range of molecular variation in a population with potentially severe fitness and phenotypic consequences for individuals, different mechanisms evolved to keep TE activity in check, allowing for a dynamic interplay between the host, its TEs and the environment in evolution. Here, we review evidence for adaptive phenotypic changes associated with TEs and the basic molecular mechanisms by which the underlying genetic changes arise: (a) domestication, (b) exaptation, (c) host gene regulation, (d) TE-mediated formation of intronless gene copies-so-called retrogenes and (e) overall increased genome plasticity. Furthermore, we review and discuss how the stress-dependent incapacitation of defence mechanisms against the activity of TEs might facilitate adaptive responses to environmental challenges and how such mechanisms might be particularly relevant in species frequently facing novel environments, such as invasive, pathogenic or parasitic species.
转座元件（TEs）对（a）长期基因组和转录组进化；（b）种群内的基因组、转录组和表观遗传变异；以及（c）个体体细胞遗传差异模式的影响的知识不断增加，这继续激发了进化生物学家对 TEs 在适应性进化中的作用的兴趣。由于 TEs 可以在种群中引发广泛的分子变异，对个体的适应性和表型有潜在的严重影响，因此进化出了不同的机制来控制 TEs 的活性，从而允许宿主、其 TEs 和环境在进化中进行动态相互作用。在这里，我们回顾了与 TEs 相关的适应性表型变化的证据，以及潜在遗传变化产生的基本分子机制：（a）驯化；（b）适应辐射；（c）宿主基因调控；（d）TE 介导的无内含子基因拷贝的形成——所谓的返座基因；以及（e）整体基因组可塑性的增加。此外，我们回顾和讨论了依赖于压力的防御机制对 TEs 活性的失能如何促进对环境挑战的适应性反应，以及这种机制在经常面临新环境的物种中如何具有特别重要的意义，例如入侵性、致病性或寄生性物种。
