RNA transcripts serve as a template for double-strand break repair in human cells.

Publication Type	Academic Article
Authors	Jalan M, Brambati A, Shah H, McDermott N, Patel J, Zhu Y, Doymaz A, Wu J, Anderson K, Gazzo A, Pareja F, Yamaguchi T, Vougiouklakis T, Ahmed-Seghir S, Steinberg P, Neiman-Golden A, Azeroglu B, Gomez-Aguilar J, da Silva E, Hussain S, Higginson D, Boutros P, Riaz N, Reis-Filho J, Powell S, Sfeir A
Journal	Nat Commun
Volume	16
Issue	1
Pagination	4349
Date Published	05/10/2025
ISSN	2041-1723
Keywords	DNA Breaks, Double-Stranded, DNA Repair, RNA, Messenger, RNA
Abstract	Double-strand breaks (DSBs) are toxic lesions that lead to genome instability. While canonical DSB repair pathways typically operate independently of RNA, growing evidence suggests that RNA:DNA hybrids and nearby transcripts can influence repair outcomes. However, whether transcript RNA can directly serve as a template for DSB repair in human cells remains unclear. In this study, we develop fluorescence and sequencing-based assays to show that RNA-containing oligonucleotides and messenger RNA can serve as templates during DSB repair. We conduct a CRISPR/Cas9-based genetic screen to identify factors that promote RNA-templated DSB repair (RT-DSBR). Of the candidate polymerases, we identify DNA polymerase zeta (Polζ) as a potential reverse transcriptase that facilitates RT-DSBR. Furthermore, analysis of cancer genome sequencing data reveals whole intron deletions - a distinct genomic signature of RT-DSBR that occurs when spliced mRNA guides repair. Altogether, our findings highlight RT-DSBR as an alternative pathway for repairing DSBs in transcribed genes, with potential mutagenic consequences.
DOI	10.1038/s41467-025-59510-x
PubMed ID	40348775
PubMed Central ID	PMC12065846