Limiting homologous recombination at stalled replication forks is essential for cell viability: DNA2 to the rescue.

Curr Genet

Genome Damage and Stability Centre, School of Life Sciences, University of Sussex, Falmer, Brighton, BN1 9RQ, UK.

Published: December 2020


Category Ranking

98%

Total Visits

921

Avg Visit Duration

2 minutes

Citations

20

Article Abstract

The disease-associated nuclease-helicase DNA2 has been implicated in DNA end-resection during DNA double-strand break repair, Okazaki fragment processing, and the recovery of stalled DNA replication forks (RFs). Its role in Okazaki fragment processing has been proposed to explain why DNA2 is indispensable for cell survival across organisms. Unexpectedly, we found that DNA2 has an essential role in suppressing homologous recombination (HR)-dependent replication restart at stalled RFs. In the absence of DNA2-mediated RF recovery, excessive HR-restart of stalled RFs results in toxic levels of abortive recombination intermediates that lead to DNA damage-checkpoint activation and terminal cell-cycle arrest. While HR proteins protect and restart stalled RFs to promote faithful genome replication, these findings show how HR-dependent replication restart is actively constrained by DNA2 to ensure cell survival. These new insights disambiguate the effects of DNA2 dysfunction on cell survival, and provide a framework to rationalize the association of DNA2 with cancer and the primordial dwarfism disorder Seckel syndrome based on its role in RF recovery.

Download full-text PDF

Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7599155PMC
http://dx.doi.org/10.1007/s00294-020-01106-7DOI Listing

Publication Analysis

Top Keywords

cell survival
12
stalled rfs
12
homologous recombination
8
replication forks
8
okazaki fragment
8
fragment processing
8
hr-dependent replication
8
replication restart
8
restart stalled
8
dna2
7

Similar Publications

Concomitant Comedications and Survival With First-Line Pembrolizumab in Advanced Non-Small-Cell Lung Cancer.

JAMA Netw Open

September 2025

Oncostat U1018, Institut National de la Santé et de la Recherche Médicale (INSERM), Ligue Contre le Cancer, Paris-Saclay University, Villejuif, France.

Importance: Antibiotics, steroids, and proton pump inhibitors (PPIs) are suspected to decrease the efficacy of immunotherapy.

Objective: To explore the association of comedications with overall survival (OS) in patients with advanced non-small-cell lung cancer (NSCLC).

Design, Setting, And Participants: This nationwide retrospective cohort study used target trial emulations of patients newly diagnosed with NSCLC from January 2015 to December 2022, identified from the French national health care database.

View Article and Find Full Text PDF

Background And Aims: Liver metastasis significantly contributes to poor survival in patients with colorectal cancer (CRC), posing therapeutic challenges due to limited understanding of its mechanisms. We aimed to identify a potential target critical for CRC liver metastasis.

Methods: We analyzed the Gene Expression Omnibus (GEO) and the Cancer Genome Atlas (TCGA) databases and identified EphrinA3 (EFNA3) as a potential clinically relevant target.

View Article and Find Full Text PDF

Background: Lung cancer (LC) is the leading cause of cancer-related deaths globally. Genetic variants in mismatch repair (MMR) genes, such as MutS homolog 2 (MSH2), MutS homolog 6 (MSH6) and MutL homolog 1 (MLH1), may influence individual susceptibility and clinical outcomes in LC.

Objective: This study investigated the associations of genetic polymorphisms in MSH2, MSH6, and MLH1 with susceptibility and survival outcomes in lung cancer patients in the Guangxi Zhuang population.

View Article and Find Full Text PDF

Deciphering the molecular landscape of acute myeloid leukemia initiation and relapse: a systems biology approach.

Med Oncol

September 2025

Division of Hematology and Blood Bank, Department of Medical Laboratory Sciences, School of Paramedical Sciences, Shiraz University of Medical Sciences, Shiraz, Iran.

Acute Myeloid Leukemia (AML) patient-derived Mesenchymal Stem Cells (MSCs) behave differently than normal ones, creating a more protective environment for leukemia cells, making relapse harder to prevent. This study aimed to identify prognostic biomarkers and elucidate relevant biological pathways in AML by leveraging microarray data and advanced bioinformatics techniques. We retrieved the GSE122917 dataset from the NCBI Gene Expression Omnibus and performed differential expression analysis (DEA) within R Studio to identify differentially expressed genes (DEGs) among healthy donors, newly diagnosed AML patients, and relapsed AML patients.

View Article and Find Full Text PDF

IL12-based phototherapeutic nanoparticles through remodeling tumor-associated macrophages combined with immunogenic tumor cell death for synergistic cancer immunotherapy.

Biomater Sci

September 2025

Key Laboratory of Biomaterials and Nanotechnology for Cancer Immunotherapy, The Tianjin Key Laboratory of Biomaterials, Institute of Biomedical Engineering, Peking Union Medical College & Chinese Academy of Medical Sciences, Tianjin, 300192, China.

Various cancer therapeutic strategies have been designed for targeting tumor-associated macrophages (TAMs), but TAM reprogramming-based monotherapy is often clinically hindered, likely due to the lack of a coordinated platform to initiate T cell-mediated immunity. Herein, we fabricated reactive oxygen species (ROS)-responsive human serum albumin (HSA)-based nanoparticles (PEG/IL12-IA NPs) consisting of indocyanine green (ICG), arginine (Arg), and interleukin 12 (IL12). Upon laser irradiation, the nanoparticles were found to be able to dissociate, thus facilitating the release of IL12.

View Article and Find Full Text PDF