Department of Molecular Biology and Genetics, Cornell University, Ithaca, New York 14850; email:
Annu Rev Genet. 2020 Nov 23;54:539-561. doi: 10.1146/annurev-genet-040620-022145. Epub 2020 Sep 21.
Transposable elements (TEs) are mobile DNA sequences that propagate within genomes. Through diverse invasion strategies, TEs have come to occupy a substantial fraction of nearly all eukaryotic genomes, and they represent a major source of genetic variation and novelty. Here we review the defining features of each major group of eukaryotic TEs and explore their evolutionary origins and relationships. We discuss how the unique biology of different TEs influences their propagation and distribution within and across genomes. Environmental and genetic factors acting at the level of the host species further modulate the activity, diversification, and fate of TEs, producing the dramatic variation in TE content observed across eukaryotes. We argue that cataloging TE diversity and dissecting the idiosyncratic behavior of individual elements are crucial to expanding our comprehension of their impact on the biology of genomes and the evolution of species.
转座元件 (TEs) 是在基因组内进行自我复制的可移动 DNA 序列。通过不同的入侵策略，TEs 已经占据了几乎所有真核生物基因组的很大一部分，它们是遗传变异和新颖性的主要来源。在这里，我们回顾了每一大类真核 TEs 的定义特征，并探讨了它们的进化起源和关系。我们讨论了不同 TEs 的独特生物学如何影响它们在基因组内和跨基因组中的传播和分布。宿主物种层面的环境和遗传因素进一步调节 TEs 的活性、多样化和命运，从而产生了在真核生物中观察到的 TE 含量的巨大差异。我们认为，对 TE 多样性进行编目并剖析各个元件的特有行为，对于扩展我们对它们对基因组生物学和物种进化的影响的理解至关重要。
