Kejnovsky Eduard, Tokan Viktor, Lexa Matej
Department of Plant Developmental Genetics, Institute of Biophysics, Academy of Sciences of the Czech Republic, Brno, Czech Republic.
Faculty of Informatics, Masaryk University Brno, Brno, Czech Republic.
Chromosome Res. 2015 Sep;23(3):615-23. doi: 10.1007/s10577-015-9491-7.
A significant part of eukaryotic genomes is formed by transposable elements (TEs) containing not only genes but also regulatory sequences. Some of the regulatory sequences located within TEs can form secondary structures like hairpins or three-stranded (triplex DNA) and four-stranded (quadruplex DNA) conformations. This review focuses on recent evidence showing that G-quadruplex-forming sequences in particular are often present in specific parts of TEs in plants and humans. We discuss the potential role of these structures in the TE life cycle as well as the impact of G-quadruplexes on replication, transcription, translation, chromatin status, and recombination. The aim of this review is to emphasize that TEs may serve as vehicles for the genomic spread of G-quadruplexes. These non-canonical DNA structures and their conformational switches may constitute another regulatory system that, together with small and long non-coding RNA molecules and proteins, contribute to the complex cellular network resulting in the large diversity of eukaryotes.
真核生物基因组的很大一部分是由转座元件（TEs）构成的，这些转座元件不仅包含基因，还包含调控序列。位于TEs内的一些调控序列可以形成二级结构，如发夹结构或三链（三链DNA）和四链（四链DNA）构象。本综述重点关注最近的证据，这些证据表明，特别是形成G-四链体的序列经常存在于植物和人类TEs的特定部位。我们讨论了这些结构在TE生命周期中的潜在作用，以及G-四链体对复制、转录、翻译、染色质状态和重组的影响。本综述的目的是强调TEs可能作为G-四链体基因组传播的载体。这些非经典DNA结构及其构象转换可能构成另一种调控系统，该系统与小的和长的非编码RNA分子以及蛋白质一起，促成了复杂的细胞网络，从而导致了真核生物的巨大多样性。
