Structural and molecular basis for transcription-replication collisions

2026-07-22

One of the sources of genome instability is the occurrence of transcription-replication collisions (TRCs). These collisions occur when the replication machinery collides with the transcription complex due to the presence of obstacles in the DNA template, such as DNA-bound proteins or structures known as R-loops, which are three-stranded nucleic acid structures that inhibit the normal progression of both systems. These R-loops are often formed during transcription, but their assembly is regulated by several cellular mechanisms that prevent the accumulation of TRCs. TRCs can potentially cause deletions, chromosomal rearrangements, and loss of genetic information due to DNA double-strand breaks generated by the collision. High levels of TRCs have been found in several types of cancer, which is a growing global health concern. Although many studies have investigated the role of TRCs in normal and cancer cells, the detailed molecular mechanism behind TRCs remains to be elucidated. The ReTraCol project aims to bring together the fields of transcription and replication to gain a deeper molecular and structural understanding of R-loop-dependent TRCs using biochemical and cryo-EM techniques. The expected results will reveal how the replication and transcription systems behave during a collision and describe the stepwise formation of TRCs. This project could lead to an understanding of the impact of TRCs in both normal and cancer cells, and potentially open new future investigations to use TRCs as a cancer target.

Germany

2026-01-01