Protein-mediated stabilization and nicking of the nontemplate DNA strand dramatically affect R-loop formation in vitro.

ABSTRACT: R-loops are an important class of non-B DNA structures that form co-transcriptionally. Using in vitro transcription and unbiased quantitative sequencing readouts, we show that the addition of single-strand DNA binding proteins co-transcriptionally can drive a 3- to 5-fold increase of R-loop frequency without significant changes to R-loop distribution. We propose that this is caused by stabilizing and preventing the collapse of short nascent R-loops. This suggests that R-loop formation is highly dynamic and highlights single strand binding proteins as players in cellular R-loop regulation. We further show that nontemplate strand DNA nicks are powerful initiators of R-loop formation, increasing R-loop frequencies by up to two orders of magnitude. Atomic force microscopy revealed that the non

SUBMITTER: Holleman E 

PROVIDER: S-EPMC12478114 | biostudies-literature | 2025 Sep

REPOSITORIES: biostudies-literature