Institut Jacques Monod, Université de Paris, CNRS, F-75006 Paris, France.
Department of Genetics & Development, Columbia University Irving Medical Center, New York, NY 10032, USA.
Cells. 2021 Jun 8;10(6):1433. doi: 10.3390/cells10061433.
RNA-containing structures, including ribonucleotide insertions, DNA:RNA hybrids and R-loops, have recently emerged as critical players in the maintenance of genome integrity. Strikingly, different enzymatic activities classically involved in genome maintenance contribute to their generation, their processing into genotoxic or repair intermediates, or their removal. Here we review how this substrate promiscuity can account for the detrimental and beneficial impacts of RNA insertions during genome metabolism. We summarize how in vivo and in vitro experiments support the contribution of DNA polymerases and homologous recombination proteins in the formation of RNA-containing structures, and we discuss the role of DNA repair enzymes in their removal. The diversity of pathways that are thus affected by RNA insertions likely reflects the ancestral function of RNA molecules in genome maintenance and transmission.
含有 RNA 的结构，包括核苷酸插入物、DNA:RNA 杂交体和 R 环，最近已成为维持基因组完整性的关键因素。引人注目的是，不同的酶活性通常涉及基因组的维持，有助于它们的产生、将其加工成遗传毒性或修复中间体，或清除它们。在这里，我们回顾了这种底物的混杂性如何解释 RNA 插入在基因组代谢过程中的有害和有益影响。我们总结了体内和体外实验如何支持 DNA 聚合酶和同源重组蛋白在形成含有 RNA 的结构中的作用，并讨论了 DNA 修复酶在其去除中的作用。受 RNA 插入影响的途径的多样性可能反映了 RNA 分子在基因组维持和传递中的古老功能。
