Project description
Molecular mechanisms of oxidative stress-induced R-loop formation and genome instability
Conflicts between DNA transcription and replication (TRCs) are one of the major sources of DNA replication stress and are linked to increased genome instability, which accelerates cancer development. TRCs are often associated with the formation of R-loops, three-stranded nucleic acid structures consisting of an RNA:DNA hybrid and displaced single-stranded DNA, which further enhance genome instability. Recent research has shown a connection among oxidative stress, replication speed, and the formation of TRCs and R-loops; however, the exact mechanism remains unclear. The goal of this project is to understand how oxidative stress leads to R-loop formation and to clarify the specific conditions that result in genome instability. The project has three parts: a) studying replication velocity, replication stalling, and R-loop formation at different stages of the S phase using DNA fiber assay and high-throughput microscopy; b) identifying genomic hotspots susceptible to replication stalling caused by R-loops through CUT&Tag and next-generation sequencing; c) correlating the specific stage of S-phase with DNA replication speed, R-loop formation, and consequent defects in chromosome segregation in mitosis under normal and stress conditions.
