Skourti-Stathaki Konstantina, Proudfoot Nicholas J
Sir William Dunn School of Pathology, University of Oxford, Oxford OX1 3RE, United Kingdom.
Genes Dev. 2014 Jul 1;28(13):1384-96. doi: 10.1101/gad.242990.114.
R loops are three-stranded nucleic acid structures that comprise nascent RNA hybridized with the DNA template, leaving the nontemplate DNA single-stranded. R loops form naturally during transcription even though their persistent formation can be a risky outcome with deleterious effects on genome integrity. On the other hand, over the last few years, an increasingly strong case has been built for R loops as potential regulators of gene expression. Therefore, understanding their function and regulation under these opposite situations is essential to fully characterize the mechanisms that control genome integrity and gene expression. Here we review recent findings about these interesting structures that highlight their opposite roles in cellular fitness.
R环是由与DNA模板杂交的新生RNA组成的三链核酸结构，使非模板DNA保持单链状态。尽管R环的持续形成可能是一个对基因组完整性有有害影响的风险结果，但它们在转录过程中会自然形成。另一方面，在过去几年中，越来越多的有力证据表明R环是基因表达的潜在调节因子。因此，了解它们在这些相反情况下的功能和调控对于全面表征控制基因组完整性和基因表达的机制至关重要。在这里，我们回顾了关于这些有趣结构的最新发现，这些发现突出了它们在细胞适应性中的相反作用。
