Single-strand breaks (SSBs) are one of the most commonly occurring endogenous lesions with the potential to give rise to cytotoxic double-strand breaks (DSBs) during DNA replication. To investigate how replication-dependent DSBs are repaired, we employed Cas9 nickase (nCas9) to generate site- and strand-specific nicks in the budding yeast genome. We found that nCas9-induced nicks are converted to mostly double-ended DSBs during S phase. Repair of replication-associated DSBs requires homologous recombination (HR) and is independent of classical non-homologous end joining. Consistent with a strong bias to repair these lesions using a sister-chromatid template, we observed minimal induction of inter-chromosomal HR by nCas9. In a genome-wide screen to identify factors necessary for the repair of replication-dependent DSBs, we recovered components of the replication-coupled nucleosome assembly (RCNA) pathway. Our findings suggest that the RCNA pathway is especially important to repair DSBs arising from nicks in the leading-strand template through acetylation of histone H3K56.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1016/j.molcel.2024.10.032 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Loss of Fbxo45 in AT2 cells leads to insufficient histone supply and initiates lung adenocarcinoma.
Cell Death Differ
December 2024
Department of Biochemistry and Molecular Cell Biology & Department of Thoracic Surgery Ren Ji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China.
Dysregulation of histone supply is implicated in various cancers, including lung adenocarcinoma (LUAD), although the underlying mechanisms remain poorly understood. Here, we demonstrate that knockout of Fbxo45 in mouse alveolar epithelial type 2 (AT2) cells leads to spontaneous LUAD. Our findings reveal that FBXO45 is a novel cell-cycle-regulated protein that is degraded upon phosphorylation by CDK1 during the S/G2 phase.
View Article and Find Full Text PDFRepair of replication-dependent double-strand breaks differs between the leading and lagging strands.
Mol Cell
November 2024
Department of Microbiology & Immunology, Columbia University Irving Medical Center, New York, NY 10032, USA; Department of Genetics & Development, Columbia University Irving Medical Center, New York, NY 10032, USA. Electronic address:
Single-strand breaks (SSBs) are one of the most commonly occurring endogenous lesions with the potential to give rise to cytotoxic double-strand breaks (DSBs) during DNA replication. To investigate how replication-dependent DSBs are repaired, we employed Cas9 nickase (nCas9) to generate site- and strand-specific nicks in the budding yeast genome. We found that nCas9-induced nicks are converted to mostly double-ended DSBs during S phase.
View Article and Find Full Text PDFSwitch-like phosphorylation of WRN integrates end-resection with RAD51 metabolism at collapsed replication forks.
Nucleic Acids Res
November 2024
Department of Environment and Health, Mechanisms, Biomarkers and Models Section, Genome Stability Group, Istituto Superiore di Sanità, Viale Regina Elena 299, 00161 Rome, Italy.
Replication-dependent DNA double-strand breaks are harmful lesions preferentially repaired by homologous recombination (HR), a process that requires processing of DNA ends to allow RAD51-mediated strand invasion. End resection and subsequent repair are two intertwined processes, but the mechanism underlying their execution is still poorly appreciated. The WRN helicase is one of the crucial factors for end resection and is instrumental in selecting the proper repair pathway.
View Article and Find Full Text PDFWhat makes pan-drug resistant? Integrative insights from genomic, transcriptomic, and phenomic analysis of clinical strains resistant to all four major classes of antifungal drugs.
Antimicrob Agents Chemother
October 2024
Wadsworth Center, New York State Department of Health, Albany, New York, USA.
The global epidemic of drug-resistant continues unabated. The initial report on pan-drug resistant (PDR) strains in a hospitalized patient in New York was unprecedented. PDR showed both known and unique mutations in the prominent gene targets of azoles, amphotericin B, echinocandins, and flucytosine.
View Article and Find Full Text PDFRepair of genomic interstrand crosslinks.
DNA Repair (Amst)
September 2024
Laboratory of Molecular Biology and Immunology, National Institute on Aging, National Institutes of Health, Baltimore, MD 21224, USA. Electronic address:
Genomic interstrand crosslinks (ICLs) are formed by reactive species generated during normal cellular metabolism, produced by the microbiome, and employed in cancer chemotherapy. While there are multiple options for replication dependent and independent ICL repair, the crucial step for each is unhooking one DNA strand from the other. Much of our insight into mechanisms of unhooking comes from powerful model systems based on plasmids with defined ICLs introduced into cells or cell free extracts.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!