The MUS81-EME1 endonuclease cleaves late replication intermediates at common fragile sites (CFSs) during early mitosis to trigger DNA-repair synthesis that ensures faithful chromosome segregation. Here, we show that these DNA transactions are promoted by RECQ5 DNA helicase in a manner dependent on its Ser727 phosphorylation by CDK1. Upon replication stress, RECQ5 associates with CFSs in early mitosis through its physical interaction with MUS81 and promotes MUS81-dependent mitotic DNA synthesis. RECQ5 depletion or mutational inactivation of its ATP-binding site, RAD51-interacting domain, or phosphorylation site causes excessive binding of RAD51 to CFS loci and impairs CFS expression. This leads to defective chromosome segregation and accumulation of CFS-associated DNA damage in G1 cells. Biochemically, RECQ5 alleviates the inhibitory effect of RAD51 on 3'-flap DNA cleavage by MUS81-EME1 through its RAD51 filament disruption activity. These data suggest that RECQ5 removes RAD51 filaments stabilizing stalled replication forks at CFSs and hence facilitates CFS cleavage by MUS81-EME1.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1016/j.molcel.2017.05.006 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Replication-Poison Treatment in BRCA1-Deficient Breast Cancer Causes MRE11 Over-Resection that Induces Single-Stranded DNA Accumulation and Mitotic Catastrophe.
Cancer Res
January 2025
INSERM U1194, Montpellier Cedex 05, Occitanie, France.
BRCA1 deficiency is observed in approximately 25% of triple-negative breast cancer (TNBC). BRCA1, a key player of homologous recombination (HR) repair, is also involved in stalled DNA replication fork protection and repair. Here, we investigated the sensitivity of BRCA1-deficient TNBC models to the frequently used replication chain terminator gemcitabine, which does not directly induce DNA breaks.
View Article and Find Full Text PDFPhosphorylation-dependent WRN-RPA interaction promotes recovery of stalled forks at secondary DNA structure.
Nat Commun
January 2025
Mechanisms, Biomarkers and Models Section - Genome Stability Group, Department of Environment and Health, Istituto Superiore di Sanità, Viale Regina Elena, 299 - 00161, Rome, Italy.
The WRN protein is vital for managing perturbed replication forks. Replication Protein A strongly enhances WRN helicase activity in specific in vitro assays. However, the in vivo significance of RPA binding to WRN has largely remained unexplored.
View Article and Find Full Text PDFIn and out of Replication Stress: PCNA/RPA1-Based Dynamics of Fork Stalling and Restart in the Same Cell.
Int J Mol Sci
January 2025
Institute of Molecular Biology, Bulgarian Academy of Sciences, Acad. G. Bonchev Str. Bl. 21, 1113 Sofia, Bulgaria.
Replication forks encounter various impediments, which induce fork stalling and threaten genome stability, yet the precise dynamics of fork stalling and restart at the single-cell level remain elusive. Herein, we devise a live-cell microscopy-based approach to follow hydroxyurea-induced fork stalling and subsequent restart at 30 s resolution. We measure two distinct processes during fork stalling.
View Article and Find Full Text PDFAbasic sites are one of the most frequent forms of DNA damage that interfere with DNA replication. However, abasic sites exhibit complex effects because they can be processed into other types of DNA damage. Thus, it remains poorly understood how abasic sites affect replisome progression, which replication-coupled repair pathways they elicit, and whether this is affected by the template strand that is damaged.
View Article and Find Full Text PDFThe replicative polymerase delta is inefficient copying repetitive DNA sequences. Error-prone translesion polymerases have been shown to switch with high-fidelity replicative polymerases to help navigate repetitive DNA. We and others have demonstrated the importance of one such translesion polymerase, polymerase Eta (pol eta), in facilitating replication at genomic regions called common fragile sites (CFS), which are difficult-to-replicate genomic regions that are hypersensitive to replication stress.
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!