Translocating RNA polymerase generates R-loops at DNA double-strand breaks without any additional factors.

ABSTRACT: The R-loops forming around DNA double-strand breaks (DSBs) within actively transcribed genes play a critical role in the DSB repair process. However, the mechanisms underlying R-loop formation at DSBs remain poorly understood, with diverse proposed models involving protein factors associated with RNA polymerase (RNAP) loading, pausing/backtracking or preexisting transcript RNA invasion. In this single-molecule study using Escherichia coli RNAP, we discovered that transcribing RNAP alone acts as a highly effective DSB sensor, responsible for generation of R-loops upon encountering downstream DSBs, without requiring any additional factors. The R-loop formation efficiency is greatly influenced by DNA end structures, ranging here from 2.8% to 73%, and notably higher on sticky ends with 3' or 5

SUBMITTER: Lim G 

PROVIDER: S-EPMC10570047 | biostudies-literature | 2023 Oct

REPOSITORIES: biostudies-literature