RT Journal Article SR Electronic T1 Replication protein A binds RNA and promotes R-loop formation JF bioRxiv FD Cold Spring Harbor Laboratory SP 2020.02.11.943977 DO 10.1101/2020.02.11.943977 A1 Olga M. Mazina A1 Srinivas Somarowthu A1 Lyudmila Y. Kadyrova A1 Andrey G. Baranovskiy A1 Tahir H. Tahirov A1 Farid A. Kadyrov A1 Alexander V. Mazin YR 2020 UL http://biorxiv.org/content/early/2020/02/12/2020.02.11.943977.abstract AB Replication protein A (RPA), a major eukaryotic ssDNA-binding protein, is essential for all metabolic processes that involve ssDNA including DNA replication, repair, and damage signaling. Surprisingly, we found here that RPA binds RNA in vitro with high affinity. Using native RIP method, we isolated RNA-RPA complexes from human cells. Furthermore, RPA promotes R-loop formation between RNA and homologous dsDNA. R-loops, the three-stranded nucleic acid structure consisting of an RNA-DNA hybrid and the displaced ssDNA strand, are common in human genome. R-loops may play an important role in transcription-coupled homologous recombination and DNA replication restart. We reconstituted the process of replication restart in vitro using RPA-generated R-loops and human DNA polymerases. These findings indicate that RPA may play a role in RNA metabolism and suggest a mechanism of genome maintenance that depends on RPA and RNA.