XPF interacts with TOP2B for R-loop processing and DNA looping on actively transcribed genes.

Chatzinikolaou G, Stratigi K, Siametis A, Goulielmaki E, Akalestou-Clocher A, Tsamardinos I, Topalis P, Austin C, Bouwman BAM, Crosetto N, Altmüller J, Garinis GA

Sci Adv 9 (45) eadi2095 [2023-11-10; online 2023-11-08]

Co-transcriptional RNA-DNA hybrids can not only cause DNA damage threatening genome integrity but also regulate gene activity in a mechanism that remains unclear. Here, we show that the nucleotide excision repair factor XPF interacts with the insulator binding protein CTCF and the cohesin subunits SMC1A and SMC3, leading to R-loop-dependent DNA looping upon transcription activation. To facilitate R-loop processing, XPF interacts and recruits with TOP2B on active gene promoters, leading to double-strand break accumulation and the activation of a DNA damage response. Abrogation of TOP2B leads to the diminished recruitment of XPF, CTCF, and the cohesin subunits to promoters of actively transcribed genes and R-loops and the concurrent impairment of CTCF-mediated DNA looping. Together, our findings disclose an essential role for XPF with TOP2B and the CTCF/cohesin complex in R-loop processing for transcription activation with important ramifications for DNA repair-deficient syndromes associated with transcription-associated DNA damage.

PubMed 37939182

DOI 10.1126/sciadv.adi2095

Crossref 10.1126/sciadv.adi2095

pmc: PMC10631727


Publications 9.5.1