1
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Uhrig ME, Sharma N, Maxwell P, Selemenakis P, Mazin AV, Wiese C. Disparate requirements for RAD54L in replication fork reversal. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.07.26.550704. [PMID: 37546955 PMCID: PMC10402051 DOI: 10.1101/2023.07.26.550704] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/08/2023]
Abstract
RAD54L is a DNA motor protein with multiple roles in homologous recombination DNA repair (HR). In vitro , RAD54L was shown to also catalyze the reversal and restoration of model replication forks. In cells, however, little is known about how RAD54L may regulate the dynamics of DNA replication. Here, we show that RAD54L restrains the progression of replication forks and functions as a fork remodeler in human cells. Analogous to HLTF, SMARCAL1, and FBH1, and consistent with a role in fork reversal, RAD54L decelerates fork progression in response to replication stress and suppresses the formation of replication-associated ssDNA gaps. Interestingly, loss of RAD54L prevents nascent strand DNA degradation in both BRCA1/2- and 53BP1-deficient cells, suggesting that RAD54L functions in both pathways of RAD51-mediated replication fork reversal. In the HLTF/SMARCAL1 pathway, RAD54L is critical, but its ability to catalyze branch migration is dispensable, indicative of its function downstream of HLTF/SMARCAL1. Conversely, in the FBH1 pathway, branch migration activity of RAD54L is essential, and FBH1 engagement is dependent on its concerted action with RAD54L. Collectively, our results reveal disparate requirements for RAD54L in two distinct RAD51-mediated fork reversal pathways, positing its potential as a future therapeutic target.
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2
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Ubieto-Capella P, Ximénez-Embún P, Giménez-Llorente D, Losada A, Muñoz J, Méndez J. A rewiring of DNA replication mediated by MRE11 exonuclease underlies primed-to-naive cell de-differentiation. Cell Rep 2024; 43:114024. [PMID: 38581679 DOI: 10.1016/j.celrep.2024.114024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2023] [Revised: 02/01/2024] [Accepted: 03/15/2024] [Indexed: 04/08/2024] Open
Abstract
Mouse embryonic stem cells (mESCs) in the primed pluripotency state, which resembles the post-implantation epiblast, can be de-differentiated in culture to a naive state that resembles the pre-implantation inner cell mass. We report that primed-to-naive mESC transition entails a significant slowdown of DNA replication forks and the compensatory activation of dormant origins. Using isolation of proteins on nascent DNA coupled to mass spectrometry, we identify key changes in replisome composition that are responsible for these effects. Naive mESC forks are enriched in MRE11 nuclease and other DNA repair proteins. MRE11 is recruited to newly synthesized DNA in response to transcription-replication conflicts, and its inhibition or genetic downregulation in naive mESCs is sufficient to restore the fork rate of primed cells. Transcriptomic analyses indicate that MRE11 exonuclease activity is required for the complete primed-to-naive mESC transition, demonstrating a direct link between DNA replication dynamics and the mESC de-differentiation process.
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Affiliation(s)
- Patricia Ubieto-Capella
- DNA Replication Group, Molecular Oncology Programme, Spanish National Cancer Research Centre (CNIO), 28029 Madrid, Spain
| | - Pilar Ximénez-Embún
- Proteomics Unit-ProteoRed-ISCIII, Biotechnology Programme, Spanish National Cancer Research Centre (CNIO), 28029 Madrid, Spain
| | - Daniel Giménez-Llorente
- Chromosome Dynamics Group, Molecular Oncology Programme, Spanish National Cancer Research Centre (CNIO), 28029 Madrid, Spain
| | - Ana Losada
- Chromosome Dynamics Group, Molecular Oncology Programme, Spanish National Cancer Research Centre (CNIO), 28029 Madrid, Spain
| | - Javier Muñoz
- Proteomics Unit-ProteoRed-ISCIII, Biotechnology Programme, Spanish National Cancer Research Centre (CNIO), 28029 Madrid, Spain
| | - Juan Méndez
- DNA Replication Group, Molecular Oncology Programme, Spanish National Cancer Research Centre (CNIO), 28029 Madrid, Spain.
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3
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Georgieva D, Wang N, Taglialatela A, Jerabek S, Reczek CR, Lim PX, Sung J, Du Q, Horiguchi M, Jasin M, Ciccia A, Baer R, Egli D. BRCA1 and 53BP1 regulate reprogramming efficiency by mediating DNA repair pathway choice at replication-associated double-strand breaks. Cell Rep 2024; 43:114006. [PMID: 38554279 DOI: 10.1016/j.celrep.2024.114006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2023] [Revised: 11/26/2023] [Accepted: 03/11/2024] [Indexed: 04/01/2024] Open
Abstract
Reprogramming to pluripotency is associated with DNA damage and requires the functions of the BRCA1 tumor suppressor. Here, we leverage separation-of-function mutations in BRCA1/2 as well as the physical and/or genetic interactions between BRCA1 and its associated repair proteins to ascertain the relevance of homology-directed repair (HDR), stalled fork protection (SFP), and replication gap suppression (RGS) in somatic cell reprogramming. Surprisingly, loss of SFP and RGS is inconsequential for the transition to pluripotency. In contrast, cells deficient in HDR, but proficient in SFP and RGS, reprogram with reduced efficiency. Conversely, the restoration of HDR function through inactivation of 53bp1 rescues reprogramming in Brca1-deficient cells, and 53bp1 loss leads to elevated HDR and enhanced reprogramming in mouse and human cells. These results demonstrate that somatic cell reprogramming is especially dependent on repair of replication-associated double-strand breaks (DSBs) by the HDR activity of BRCA1 and BRCA2 and can be improved in the absence of 53BP1.
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Affiliation(s)
- Daniela Georgieva
- Department of Pediatrics and Naomi Berrie Diabetes Center, Columbia University Irving Medical Center, New York, NY 10032, USA; Columbia University Stem Cell Initiative, New York, NY 10032, USA
| | - Ning Wang
- Department of Pediatrics and Naomi Berrie Diabetes Center, Columbia University Irving Medical Center, New York, NY 10032, USA; Columbia University Stem Cell Initiative, New York, NY 10032, USA
| | - Angelo Taglialatela
- Columbia University Stem Cell Initiative, New York, NY 10032, USA; Department of Genetics and Development, Herbert Irving Comprehensive Cancer Center, Columbia University Irving Medical Center, New York, NY 10032, USA
| | - Stepan Jerabek
- Department of Pediatrics and Naomi Berrie Diabetes Center, Columbia University Irving Medical Center, New York, NY 10032, USA; Columbia University Stem Cell Initiative, New York, NY 10032, USA; Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Flemingovo namesti 542/2, 160 00 Praha 6, Czech Republic
| | - Colleen R Reczek
- Department of Pathology & Cell Biology, Institute for Cancer Genetics, Columbia University Irving Medical Center, New York, NY 10032, USA
| | - Pei Xin Lim
- Developmental Biology Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
| | - Julie Sung
- Department of Pediatrics and Naomi Berrie Diabetes Center, Columbia University Irving Medical Center, New York, NY 10032, USA
| | - Qian Du
- Department of Pediatrics and Naomi Berrie Diabetes Center, Columbia University Irving Medical Center, New York, NY 10032, USA
| | - Michiko Horiguchi
- Department of Pathology & Cell Biology, Institute for Cancer Genetics, Columbia University Irving Medical Center, New York, NY 10032, USA
| | - Maria Jasin
- Developmental Biology Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
| | - Alberto Ciccia
- Columbia University Stem Cell Initiative, New York, NY 10032, USA; Department of Genetics and Development, Herbert Irving Comprehensive Cancer Center, Columbia University Irving Medical Center, New York, NY 10032, USA
| | - Richard Baer
- Department of Pathology & Cell Biology, Institute for Cancer Genetics, Columbia University Irving Medical Center, New York, NY 10032, USA
| | - Dieter Egli
- Department of Pediatrics and Naomi Berrie Diabetes Center, Columbia University Irving Medical Center, New York, NY 10032, USA; Columbia University Stem Cell Initiative, New York, NY 10032, USA; Department of Obstetrics and Gynecology, Columbia University Irving Medical Center, New York, NY 10032, USA.
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4
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Muñoz S, Blanco-Romero E, González-Acosta D, Rodriguez-Acebes S, Megías D, Lopes M, Méndez J. RAD51 restricts DNA over-replication from re-activated origins. EMBO J 2024; 43:1043-1064. [PMID: 38360996 PMCID: PMC10942984 DOI: 10.1038/s44318-024-00038-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2023] [Revised: 01/11/2024] [Accepted: 01/12/2024] [Indexed: 02/17/2024] Open
Abstract
Eukaryotic cells rely on several mechanisms to ensure that the genome is duplicated precisely once in each cell division cycle, preventing DNA over-replication and genomic instability. Most of these mechanisms limit the activity of origin licensing proteins to prevent the reactivation of origins that have already been used. Here, we have investigated whether additional controls restrict the extension of re-replicated DNA in the event of origin re-activation. In a genetic screening in cells forced to re-activate origins, we found that re-replication is limited by RAD51 and enhanced by FBH1, a RAD51 antagonist. In the presence of chromatin-bound RAD51, forks stemming from re-fired origins are slowed down, leading to frequent events of fork reversal. Eventual re-initiation of DNA synthesis mediated by PRIMPOL creates ssDNA gaps that facilitate the partial elimination of re-duplicated DNA by MRE11 exonuclease. In the absence of RAD51, these controls are abrogated and re-replication forks progress much longer than in normal conditions. Our study uncovers a safeguard mechanism to protect genome stability in the event of origin reactivation.
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Affiliation(s)
- Sergio Muñoz
- DNA Replication Group, Molecular Oncology Programme, Spanish National Cancer Research Centre (CNIO), Melchor Fernández Almagro 3, 28029, Madrid, Spain
| | - Elena Blanco-Romero
- DNA Replication Group, Molecular Oncology Programme, Spanish National Cancer Research Centre (CNIO), Melchor Fernández Almagro 3, 28029, Madrid, Spain
| | - Daniel González-Acosta
- DNA Replication Group, Molecular Oncology Programme, Spanish National Cancer Research Centre (CNIO), Melchor Fernández Almagro 3, 28029, Madrid, Spain
- Institute of Molecular Cancer Research, University of Zurich, Winterthurerstrasse 190, 8057, Zurich, Switzerland
| | - Sara Rodriguez-Acebes
- DNA Replication Group, Molecular Oncology Programme, Spanish National Cancer Research Centre (CNIO), Melchor Fernández Almagro 3, 28029, Madrid, Spain
| | - Diego Megías
- Confocal Microscopy Unit, Biotechnology Programme, Spanish National Cancer Research Centre (CNIO), Melchor Fernández Almagro 3, 28029, Madrid, Spain
- Advanced Optical Microscopy Unit, Central Core Facilities, Instituto de Salud Carlos III, Madrid, Spain
| | - Massimo Lopes
- Institute of Molecular Cancer Research, University of Zurich, Winterthurerstrasse 190, 8057, Zurich, Switzerland
| | - Juan Méndez
- DNA Replication Group, Molecular Oncology Programme, Spanish National Cancer Research Centre (CNIO), Melchor Fernández Almagro 3, 28029, Madrid, Spain.
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5
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Wu W, Wu W, Zhou Y, Yang Q, Zhuang S, Zhong C, Li W, Li A, Zhao W, Yin X, Zu X, Chak-Lui Wong C, Yin D, Hu K, Cai M. The dePARylase NUDT16 promotes radiation resistance of cancer cells by blocking SETD3 for degradation via reversing its ADP-ribosylation. J Biol Chem 2024; 300:105671. [PMID: 38272222 PMCID: PMC10926213 DOI: 10.1016/j.jbc.2024.105671] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2023] [Revised: 12/30/2023] [Accepted: 01/02/2024] [Indexed: 01/27/2024] Open
Abstract
Poly(ADP-ribosyl)ation (PARylation) is a critical posttranslational modification that plays a vital role in maintaining genomic stability via a variety of molecular mechanisms, including activation of replication stress and the DNA damage response. The nudix hydrolase NUDT16 was recently identified as a phosphodiesterase that is responsible for removing ADP-ribose units and that plays an important role in DNA repair. However, the roles of NUDT16 in coordinating replication stress and cell cycle progression remain elusive. Here, we report that SETD3, which is a member of the SET-domain containing protein (SETD) family, is a novel substrate for NUDT16, that its protein levels fluctuate during cell cycle progression, and that its stability is strictly regulated by NUDT16-mediated dePARylation. Moreover, our data indicated that the E3 ligase CHFR is responsible for the recognition and degradation of endogenous SETD3 in a PARP1-mediated PARylation-dependent manner. Mechanistically, we revealed that SETD3 associates with BRCA2 and promotes its recruitment to stalled replication fork and DNA damage sites upon replication stress or DNA double-strand breaks, respectively. Importantly, depletion of SETD3 in NUDT16-deficient cells did not further exacerbate DNA breaks or enhance the sensitivity of cancer cells to IR exposure, suggesting that the NUDT16-SETD3 pathway may play critical roles in the induction of tolerance to radiotherapy. Collectively, these data showed that NUDT16 functions as a key upstream regulator of SETD3 protein stability by reversing the ADP-ribosylation of SETD3, and NUDT16 participates in the resolution of replication stress and facilitates HR repair.
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Affiliation(s)
- Weijun Wu
- Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Guangdong-Hong Kong Joint Laboratory for RNA Medicine, Medical Research Center, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, China; Department of Oncology Radiotherapy, The First Affiliated Hospital, Hengyang Medical School, University of South China, Hengyang, Hunan, China
| | - Wenjing Wu
- Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Guangdong-Hong Kong Joint Laboratory for RNA Medicine, Medical Research Center, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, China; Department of Breast Oncology, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, China
| | - Yingshi Zhou
- Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Guangdong-Hong Kong Joint Laboratory for RNA Medicine, Medical Research Center, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, China; Department of Ultrasound, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, China
| | - Qiao Yang
- Department of Oncology Radiotherapy, The First Affiliated Hospital, Hengyang Medical School, University of South China, Hengyang, Hunan, China
| | - Shuting Zhuang
- Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Guangdong-Hong Kong Joint Laboratory for RNA Medicine, Medical Research Center, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, China
| | - Caixia Zhong
- Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Guangdong-Hong Kong Joint Laboratory for RNA Medicine, Medical Research Center, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, China
| | - Wenjia Li
- Department of Pathology, The First Affiliated Hospital, Zhengzhou University, Zhengzhou, China
| | - Aixin Li
- Department of Oncology Radiotherapy, The First Affiliated Hospital, Hengyang Medical School, University of South China, Hengyang, Hunan, China
| | - Wanzhen Zhao
- Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Guangdong-Hong Kong Joint Laboratory for RNA Medicine, Medical Research Center, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, China; Department of Oncology Radiotherapy, The First Affiliated Hospital, Hengyang Medical School, University of South China, Hengyang, Hunan, China
| | - Xiaomin Yin
- Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Guangdong-Hong Kong Joint Laboratory for RNA Medicine, Medical Research Center, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, China; Department of Oncology Radiotherapy, The First Affiliated Hospital, Hengyang Medical School, University of South China, Hengyang, Hunan, China
| | - Xuyu Zu
- Cancer Research Institute, The First Affiliated Hospital, Hengyang Medical School, University of South China, Hengyang, Hunan, China
| | - Carmen Chak-Lui Wong
- Li Ka Shing Faculty of Medicine, Department of Pathology, The University of Hong Kong, Hong Kong, Guangdong, China
| | - Dong Yin
- Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Guangdong-Hong Kong Joint Laboratory for RNA Medicine, Medical Research Center, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, China.
| | - Kaishun Hu
- Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Guangdong-Hong Kong Joint Laboratory for RNA Medicine, Medical Research Center, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, China.
| | - Manbo Cai
- Department of Oncology Radiotherapy, The First Affiliated Hospital, Hengyang Medical School, University of South China, Hengyang, Hunan, China.
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6
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Ito M, Fujita Y, Shinohara A. Positive and negative regulators of RAD51/DMC1 in homologous recombination and DNA replication. DNA Repair (Amst) 2024; 134:103613. [PMID: 38142595 DOI: 10.1016/j.dnarep.2023.103613] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2023] [Revised: 12/10/2023] [Accepted: 12/10/2023] [Indexed: 12/26/2023]
Abstract
RAD51 recombinase plays a central role in homologous recombination (HR) by forming a nucleoprotein filament on single-stranded DNA (ssDNA) to catalyze homology search and strand exchange between the ssDNA and a homologous double-stranded DNA (dsDNA). The catalytic activity of RAD51 assembled on ssDNA is critical for the DNA-homology-mediated repair of DNA double-strand breaks in somatic and meiotic cells and restarting stalled replication forks during DNA replication. The RAD51-ssDNA complex also plays a structural role in protecting the regressed/reversed replication fork. Two types of regulators control RAD51 filament formation, stability, and dynamics, namely positive regulators, including mediators, and negative regulators, so-called remodelers. The appropriate balance of action by the two regulators assures genome stability. This review describes the roles of positive and negative RAD51 regulators in HR and DNA replication and its meiosis-specific homolog DMC1 in meiotic recombination. We also provide future study directions for a comprehensive understanding of RAD51/DMC1-mediated regulation in maintaining and inheriting genome integrity.
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Affiliation(s)
- Masaru Ito
- Institute for Protein Research, Osaka University, Yamadaoka 3-2, Suita, Osaka 565-0871, Japan.
| | - Yurika Fujita
- Institute for Protein Research, Osaka University, Yamadaoka 3-2, Suita, Osaka 565-0871, Japan.
| | - Akira Shinohara
- Institute for Protein Research, Osaka University, Yamadaoka 3-2, Suita, Osaka 565-0871, Japan.
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7
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Ellison V, Polotskaia A, Xiao G, Leybengrub P, Qiu W, Lee R, Hendrickson R, Hu W, Bargonetti J. A CANCER PERSISTENT DNA REPAIR CIRCUIT DRIVEN BY MDM2, MDM4 (MDMX), AND MUTANT P53 FOR RECRUITMENT OF MDC1 AND 53BP1 TO CHROMATIN. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.01.20.576487. [PMID: 38328189 PMCID: PMC10849484 DOI: 10.1101/2024.01.20.576487] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/09/2024]
Abstract
The influence of the metastasis promoting proteins mutant p53 (mtp53) and MDM2 on Cancer Persistent Repair (CPR) to promote cancer cell survival is understudied. Interactions between the DNA repair choice protein 53BP1 and wild type tumor suppressor protein p53 (wtp53) regulates cell cycle control. Cancer cells often express elevated levels of transcriptionally inactive missense mutant p53 (mtp53) that interacts with MDM2 and MDM4/MDMX (herein called MDMX). The ability of mtp53 to maintain a 53BP1 interaction while in the context of interactions with MDM2 and MDMX has not been described. We asked if MDM2 regulates chromatin-based phosphorylation events in the context of mtp53 by comparing the chromatin of T47D breast cancer cells with and without MDM2 in a phospho-peptide stable isotope labeling in cell culture (SILAC) screen. We found reduced phospho-53BP1 chromatin association, which we confirmed by chromatin fractionation and immunofluorescence in multiple breast cancer cell lines. We used the Proximity Ligation Assay (PLA) in breast cancer cell lines and detected 53BP1 in close proximity to mtp53, MDM2, and the DNA repair protein MDC1. Through disruption of the mtp53-MDM2 interaction, by either Nutlin 3a or a mtp53 R273H C-terminal deletion, we uncovered that mtp53 was required for MDM2-53BP1 interaction foci. Our data suggests that mtp53 works with MDM2 and 53BP1 to promote CPR and cell survival.
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Affiliation(s)
- Viola Ellison
- Hunter College, The Department of Biological Sciences, Belfer Research Building, New York, NY
| | - Alla Polotskaia
- Hunter College, The Department of Biological Sciences, Belfer Research Building, New York, NY
| | - Gu Xiao
- Hunter College, The Department of Biological Sciences, Belfer Research Building, New York, NY
| | - Pamella Leybengrub
- Hunter College, The Department of Biological Sciences, Belfer Research Building, New York, NY
| | - Weigang Qiu
- Hunter College, The Department of Biological Sciences, Belfer Research Building, New York, NY
| | - Rusia Lee
- Hunter College, The Department of Biological Sciences, Belfer Research Building, New York, NY
- The Graduate Center City University of New York, Departments of Biology and Biochemistry, New York, NY
| | | | - Wenwei Hu
- Rutgers Cancer Institute of New Jersey, Rutgers University, New Brunswick, NJ
| | - Jill Bargonetti
- Hunter College, The Department of Biological Sciences, Belfer Research Building, New York, NY
- The Graduate Center City University of New York, Departments of Biology and Biochemistry, New York, NY
- Weill Cornell Medical College, Department of Cell and Developmental Biology, New York, NY
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8
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Xu MJ, Jordan PW. SMC5/6 Promotes Replication Fork Stability via Negative Regulation of the COP9 Signalosome. Int J Mol Sci 2024; 25:952. [PMID: 38256025 PMCID: PMC10815603 DOI: 10.3390/ijms25020952] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2023] [Revised: 01/06/2024] [Accepted: 01/10/2024] [Indexed: 01/24/2024] Open
Abstract
It is widely accepted that DNA replication fork stalling is a common occurrence during cell proliferation, but there are robust mechanisms to alleviate this and ensure DNA replication is completed prior to chromosome segregation. The SMC5/6 complex has consistently been implicated in the maintenance of replication fork integrity. However, the essential role of the SMC5/6 complex during DNA replication in mammalian cells has not been elucidated. In this study, we investigate the molecular consequences of SMC5/6 loss at the replication fork in mouse embryonic stem cells (mESCs), employing the auxin-inducible degron (AID) system to deplete SMC5 acutely and reversibly in the defined cellular contexts of replication fork stall and restart. In SMC5-depleted cells, we identify a defect in the restart of stalled replication forks, underpinned by excess MRE11-mediated fork resection and a perturbed localization of fork protection factors to the stalled fork. Previously, we demonstrated a physical and functional interaction of SMC5/6 with the COP9 signalosome (CSN), a cullin deneddylase that enzymatically regulates cullin ring ligase (CRL) activity. Employing a combination of DNA fiber techniques, the AID system, small-molecule inhibition assays, and immunofluorescence microscopy analyses, we show that SMC5/6 promotes the localization of fork protection factors to stalled replication forks by negatively modulating the COP9 signalosome (CSN). We propose that the SMC5/6-mediated modulation of the CSN ensures that CRL activity and their roles in DNA replication fork stabilization are maintained to allow for efficient replication fork restart when a replication fork stall is alleviated.
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Affiliation(s)
- Michelle J. Xu
- Department of Biochemistry and Molecular Biology, Johns Hopkins University Bloomberg School of Public Health, Baltimore, MD 21205, USA
| | - Philip W. Jordan
- Department of Biochemistry and Molecular Biology, Johns Hopkins University Bloomberg School of Public Health, Baltimore, MD 21205, USA
- Department of Biochemistry and Molecular Biology, Uniformed Services University of the Health Sciences, Bethesda, MD 20814, USA
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9
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Tirado-Class N, Hathaway C, Nelligan A, Nguyen T, Dungrawala H. DCAF14 regulates CDT2 to promote SET8-dependent replication fork protection. Life Sci Alliance 2024; 7:e202302230. [PMID: 37940188 PMCID: PMC10631547 DOI: 10.26508/lsa.202302230] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Revised: 10/24/2023] [Accepted: 10/26/2023] [Indexed: 11/10/2023] Open
Abstract
DDB1- and CUL4-associated factors (DCAFs) CDT2 and DCAF14 are substrate receptors for Cullin4-RING E3 ubiquitin ligase (CRL4) complexes. CDT2 is responsible for PCNA-coupled proteolysis of substrates CDT1, p21, and SET8 during S-phase of cell cycle. DCAF14 functions at stalled replication forks to promote genome stability, but the mechanism is unknown. We find that DCAF14 mediates replication fork protection by regulating CRL4CDT2 activity. Absence of DCAF14 causes increased proteasomal degradation of CDT2 substrates. When forks are challenged with replication stress, increased CDT2 function causes stalled fork collapse and impairs fork recovery in DCAF14-deficient conditions. We further show that stalled fork protection is dependent on CDT2 substrate SET8 and does not involve p21 and CDT1. Like DCAF14, SET8 blocks nuclease-mediated digestion of nascent DNA at remodeled replication forks. Thus, unregulated CDT2-mediated turnover of SET8 triggers nascent strand degradation when DCAF14 is absent. We propose that DCAF14 controls CDT2 activity at stalled replication forks to facilitate SET8 function in safeguarding genomic integrity.
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Affiliation(s)
- Neysha Tirado-Class
- Department of Molecular Biosciences, University of South Florida, Tampa, FL, USA
| | - Caitlin Hathaway
- Department of Molecular Biosciences, University of South Florida, Tampa, FL, USA
| | - Anthony Nelligan
- Department of Molecular Biosciences, University of South Florida, Tampa, FL, USA
| | - Thuan Nguyen
- Department of Molecular Biosciences, University of South Florida, Tampa, FL, USA
| | - Huzefa Dungrawala
- Department of Molecular Biosciences, University of South Florida, Tampa, FL, USA
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10
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González-Acosta D, Lopes M. DNA replication and replication stress response in the context of nuclear architecture. Chromosoma 2024; 133:57-75. [PMID: 38055079 PMCID: PMC10904558 DOI: 10.1007/s00412-023-00813-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2023] [Revised: 10/23/2023] [Accepted: 10/24/2023] [Indexed: 12/07/2023]
Abstract
The DNA replication process needs to be coordinated with other DNA metabolism transactions and must eventually extend to the full genome, regardless of chromatin status, gene expression, secondary structures and DNA lesions. Completeness and accuracy of DNA replication are crucial to maintain genome integrity, limiting transformation in normal cells and offering targeting opportunities for proliferating cancer cells. DNA replication is thus tightly coordinated with chromatin dynamics and 3D genome architecture, and we are only beginning to understand the underlying molecular mechanisms. While much has recently been discovered on how DNA replication initiation is organised and modulated in different genomic regions and nuclear territories-the so-called "DNA replication program"-we know much less on how the elongation of ongoing replication forks and particularly the response to replication obstacles is affected by the local nuclear organisation. Also, it is still elusive how specific components of nuclear architecture participate in the replication stress response. Here, we review known mechanisms and factors orchestrating replication initiation, and replication fork progression upon stress, focusing on recent evidence linking genome organisation and nuclear architecture with the cellular responses to replication interference, and highlighting open questions and future challenges to explore this exciting new avenue of research.
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Affiliation(s)
| | - Massimo Lopes
- Institute of Molecular Cancer Research, University of Zurich, Zurich, Switzerland.
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11
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Nickoloff JA, Jaiswal AS, Sharma N, Williamson EA, Tran MT, Arris D, Yang M, Hromas R. Cellular Responses to Widespread DNA Replication Stress. Int J Mol Sci 2023; 24:16903. [PMID: 38069223 PMCID: PMC10707325 DOI: 10.3390/ijms242316903] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Revised: 11/22/2023] [Accepted: 11/27/2023] [Indexed: 12/18/2023] Open
Abstract
Replicative DNA polymerases are blocked by nearly all types of DNA damage. The resulting DNA replication stress threatens genome stability. DNA replication stress is also caused by depletion of nucleotide pools, DNA polymerase inhibitors, and DNA sequences or structures that are difficult to replicate. Replication stress triggers complex cellular responses that include cell cycle arrest, replication fork collapse to one-ended DNA double-strand breaks, induction of DNA repair, and programmed cell death after excessive damage. Replication stress caused by specific structures (e.g., G-rich sequences that form G-quadruplexes) is localized but occurs during the S phase of every cell division. This review focuses on cellular responses to widespread stress such as that caused by random DNA damage, DNA polymerase inhibition/nucleotide pool depletion, and R-loops. Another form of global replication stress is seen in cancer cells and is termed oncogenic stress, reflecting dysregulated replication origin firing and/or replication fork progression. Replication stress responses are often dysregulated in cancer cells, and this too contributes to ongoing genome instability that can drive cancer progression. Nucleases play critical roles in replication stress responses, including MUS81, EEPD1, Metnase, CtIP, MRE11, EXO1, DNA2-BLM, SLX1-SLX4, XPF-ERCC1-SLX4, Artemis, XPG, FEN1, and TATDN2. Several of these nucleases cleave branched DNA structures at stressed replication forks to promote repair and restart of these forks. We recently defined roles for EEPD1 in restarting stressed replication forks after oxidative DNA damage, and for TATDN2 in mitigating replication stress caused by R-loop accumulation in BRCA1-defective cells. We also discuss how insights into biological responses to genome-wide replication stress can inform novel cancer treatment strategies that exploit synthetic lethal relationships among replication stress response factors.
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Affiliation(s)
- Jac A. Nickoloff
- Department of Environmental and Radiological Health Sciences, Colorado State University, Ft. Collins, CO 80523, USA
| | - Aruna S. Jaiswal
- Department of Medicine and the Mays Cancer Center, The University of Texas Health Science Center San Antonio, San Antonio, TX 78229, USA; (A.S.J.); (M.T.T.); (R.H.)
| | - Neelam Sharma
- Department of Environmental and Radiological Health Sciences, Colorado State University, Ft. Collins, CO 80523, USA
| | - Elizabeth A. Williamson
- Department of Medicine and the Mays Cancer Center, The University of Texas Health Science Center San Antonio, San Antonio, TX 78229, USA; (A.S.J.); (M.T.T.); (R.H.)
| | - Manh T. Tran
- Department of Medicine and the Mays Cancer Center, The University of Texas Health Science Center San Antonio, San Antonio, TX 78229, USA; (A.S.J.); (M.T.T.); (R.H.)
| | - Dominic Arris
- Department of Medicine and the Mays Cancer Center, The University of Texas Health Science Center San Antonio, San Antonio, TX 78229, USA; (A.S.J.); (M.T.T.); (R.H.)
| | - Ming Yang
- Department of Medicine and the Mays Cancer Center, The University of Texas Health Science Center San Antonio, San Antonio, TX 78229, USA; (A.S.J.); (M.T.T.); (R.H.)
| | - Robert Hromas
- Department of Medicine and the Mays Cancer Center, The University of Texas Health Science Center San Antonio, San Antonio, TX 78229, USA; (A.S.J.); (M.T.T.); (R.H.)
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12
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Rosso I, Jones-Weinert C, Rossiello F, Cabrini M, Brambillasca S, Munoz-Sagredo L, Lavagnino Z, Martini E, Tedone E, Garre' M, Aguado J, Parazzoli D, Mione M, Shay JW, Mercurio C, d'Adda di Fagagna F. Alternative lengthening of telomeres (ALT) cells viability is dependent on C-rich telomeric RNAs. Nat Commun 2023; 14:7086. [PMID: 37925537 PMCID: PMC10625592 DOI: 10.1038/s41467-023-42831-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2022] [Accepted: 10/23/2023] [Indexed: 11/06/2023] Open
Abstract
Alternative lengthening of telomeres (ALT) is a telomere maintenance mechanism activated in ~10-15% of cancers, characterized by telomeric damage. Telomeric damage-induced long non-coding RNAs (dilncRNAs) are transcribed at dysfunctional telomeres and contribute to telomeric DNA damage response (DDR) activation and repair. Here we observed that telomeric dilncRNAs are preferentially elevated in ALT cells. Inhibition of C-rich (teloC) dilncRNAs with antisense oligonucleotides leads to DNA replication stress responses, increased genomic instability, and apoptosis induction selectively in ALT cells. Cell death is dependent on DNA replication and is increased by DNA replication stress. Mechanistically, teloC dilncRNA inhibition reduces RAD51 and 53BP1 recruitment to telomeres, boosts the engagement of BIR machinery, and increases C-circles and telomeric sister chromatid exchanges, without increasing telomeric non-S phase synthesis. These results indicate that teloC dilncRNA is necessary for a coordinated recruitment of DDR factors to ALT telomeres and it is essential for ALT cancer cells survival.
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Affiliation(s)
- Ilaria Rosso
- IFOM ETS - The AIRC Institute of Molecular Oncology, Milan, Italy
| | - Corey Jones-Weinert
- IFOM ETS - The AIRC Institute of Molecular Oncology, Milan, Italy
- The Salk Institute for Biological Studies, La Jolla, CA, USA
| | | | - Matteo Cabrini
- IFOM ETS - The AIRC Institute of Molecular Oncology, Milan, Italy
| | - Silvia Brambillasca
- IFOM ETS - The AIRC Institute of Molecular Oncology (Experimental Therapeutics Program), Milan, Italy
| | - Leonel Munoz-Sagredo
- Institute of Biological and Chemical Systems - Functional Molecular Systems (IBCS-FMS), Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany
- School of Medicine, Universidad de Valparaiso, Valparaiso, Chile
| | - Zeno Lavagnino
- IFOM ETS - The AIRC Institute of Molecular Oncology, Milan, Italy
| | - Emanuele Martini
- IFOM ETS - The AIRC Institute of Molecular Oncology, Milan, Italy
- Dipartimento di Oncologia ed Emato-Oncologia, Università degli Studi di Milano, Milan, Italy
| | - Enzo Tedone
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Massimiliano Garre'
- IFOM ETS - The AIRC Institute of Molecular Oncology, Milan, Italy
- RCSI, Royal College of Surgeons in Ireland, Department of Chemistry, Dublin, Ireland
| | - Julio Aguado
- IFOM ETS - The AIRC Institute of Molecular Oncology, Milan, Italy
- Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, St Lucia, QLD, Australia
| | - Dario Parazzoli
- IFOM ETS - The AIRC Institute of Molecular Oncology, Milan, Italy
| | - Marina Mione
- Department of Cellular, Computational and Integrative Biology - CIBIO, University of Trento, Trento, Italy
| | - Jerry W Shay
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Ciro Mercurio
- IFOM ETS - The AIRC Institute of Molecular Oncology (Experimental Therapeutics Program), Milan, Italy
| | - Fabrizio d'Adda di Fagagna
- IFOM ETS - The AIRC Institute of Molecular Oncology, Milan, Italy.
- Institute of Molecular Genetics IGM-CNR "Luigi Luca Cavalli-Sforza", Pavia, Italy.
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13
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Adolph MB, Garje AS, Balakrishnan S, Morati F, Modesti M, Chazin WJ, Cortez D. CRISPR-dependent Base Editing Screens Identify Separation of Function Mutants of RADX with Altered RAD51 Regulatory Activity. J Mol Biol 2023; 435:168236. [PMID: 37572935 PMCID: PMC10530557 DOI: 10.1016/j.jmb.2023.168236] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2023] [Revised: 08/01/2023] [Accepted: 08/04/2023] [Indexed: 08/14/2023]
Abstract
RAD51 forms nucleoprotein filaments to promote homologous recombination, replication fork reversal, and fork protection. Numerous factors regulate the stability of these filaments and improper regulation leads to genomic instability and ultimately disease including cancer. RADX is a single stranded DNA binding protein that modulates RAD51 filament stability. Here, we utilize a CRISPR-dependent base editing screen to tile mutations across RADX to delineate motifs required for RADX function. We identified separation of function mutants of RADX that bind DNA and RAD51 but have a reduced ability to stimulate its ATP hydrolysis activity. Cells expressing these RADX mutants accumulate RAD51 on chromatin, exhibit replication defects, have reduced growth, accumulate DNA damage, and are hypersensitive to DNA damage and replication stress. These results indicate that RADX must promote RAD51 ATP turnover to regulate RAD51 and genome stability during DNA replication.
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Affiliation(s)
- Madison B Adolph
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Atharv S Garje
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Swati Balakrishnan
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN, USA; Center for Structural Biology, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Florian Morati
- Cancer Research Center of Marseille, Department of Genome Integrity, CNRS UMR7258, Inserm U1068, Institut Paoli-Calmettes, Aix Marseille Univ, Marseille, France
| | - Mauro Modesti
- Cancer Research Center of Marseille, Department of Genome Integrity, CNRS UMR7258, Inserm U1068, Institut Paoli-Calmettes, Aix Marseille Univ, Marseille, France
| | - Walter J Chazin
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN, USA; Center for Structural Biology, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - David Cortez
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN, USA.
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14
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Liu W, Polaczek P, Roubal I, Meng Y, Choe WC, Caron MC, Sedgeman C, Xi Y, Liu C, Wu Q, Zheng L, Masson JY, Shen B, Campbell J. FANCD2 and RAD51 recombinase directly inhibit DNA2 nuclease at stalled replication forks and FANCD2 acts as a novel RAD51 mediator in strand exchange to promote genome stability. Nucleic Acids Res 2023; 51:9144-9165. [PMID: 37526271 PMCID: PMC10516637 DOI: 10.1093/nar/gkad624] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2022] [Revised: 06/17/2023] [Accepted: 07/28/2023] [Indexed: 08/02/2023] Open
Abstract
FANCD2 protein, a key coordinator and effector of the interstrand crosslink repair pathway, is also required to prevent excessive nascent strand degradation at hydroxyurea-induced stalled forks. The RAD51 recombinase has also been implicated in regulation of resection at stalled replication forks. The mechanistic contributions of these proteins to fork protection are not well understood. Here, we used purified FANCD2 and RAD51 to study how each protein regulates DNA resection at stalled forks. We characterized three mechanisms of FANCD2-mediated fork protection: (1) The N-terminal domain of FANCD2 inhibits the essential DNA2 nuclease activity by directly binding to DNA2 accounting for over-resection in FANCD2 defective cells. (2) Independent of dimerization with FANCI, FANCD2 itself stabilizes RAD51 filaments to inhibit multiple nucleases, including DNA2, MRE11 and EXO1. (3) Unexpectedly, we uncovered a new FANCD2 function: by stabilizing RAD51 filaments, FANCD2 acts to stimulate the strand exchange activity of RAD51. Our work biochemically explains non-canonical mechanisms by which FANCD2 and RAD51 protect stalled forks. We propose a model in which the strand exchange activity of FANCD2 provides a simple molecular explanation for genetic interactions between FANCD2 and BRCA2 in the FA/BRCA fork protection pathway.
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Affiliation(s)
- Wenpeng Liu
- Braun Laboratories, California Institute of Technology, Pasadena, CA 91125, USA
- Colleges of Life Sciences, Zhejiang University, Hangzhou, Zhejiang 310027, China
| | - Piotr Polaczek
- Braun Laboratories, California Institute of Technology, Pasadena, CA 91125, USA
| | - Ivan Roubal
- Braun Laboratories, California Institute of Technology, Pasadena, CA 91125, USA
| | - Yuan Meng
- Department of Cancer Genetics and Epigenetics, Beckman Research Institute, City of Hope, 1500 East Duarte Road, Duarte, CA 91010-3000, USA
- Colleges of Life Sciences, Zhejiang University, Hangzhou, Zhejiang 310027, China
| | - Won-chae Choe
- Braun Laboratories, California Institute of Technology, Pasadena, CA 91125, USA
| | - Marie-Christine Caron
- Genome Stability Laboratory, CHU de Québec Research Center, HDQ Pavilion, Oncology Division, 9 McMahon, Québec City, QC G1R 3S3, Canada
| | - Carl A Sedgeman
- Braun Laboratories, California Institute of Technology, Pasadena, CA 91125, USA
| | - Yu Xi
- Colleges of Life Sciences, Zhejiang University, Hangzhou, Zhejiang 310027, China
| | - Changwei Liu
- Department of Cancer Genetics and Epigenetics, Beckman Research Institute, City of Hope, 1500 East Duarte Road, Duarte, CA 91010-3000, USA
- Colleges of Life Sciences, Zhejiang University, Hangzhou, Zhejiang 310027, China
| | - Qiong Wu
- Department of Cancer Genetics and Epigenetics, Beckman Research Institute, City of Hope, 1500 East Duarte Road, Duarte, CA 91010-3000, USA
| | - Li Zheng
- Department of Cancer Genetics and Epigenetics, Beckman Research Institute, City of Hope, 1500 East Duarte Road, Duarte, CA 91010-3000, USA
| | - Jean-Yves Masson
- Genome Stability Laboratory, CHU de Québec Research Center, HDQ Pavilion, Oncology Division, 9 McMahon, Québec City, QC G1R 3S3, Canada
- Department of Molecular Biology, Medical Biochemistry and Pathology; Laval University Cancer Research Center, Québec City, QC G1V 0A6, Canada
| | - Binghui Shen
- Department of Cancer Genetics and Epigenetics, Beckman Research Institute, City of Hope, 1500 East Duarte Road, Duarte, CA 91010-3000, USA
| | - Judith L Campbell
- Braun Laboratories, California Institute of Technology, Pasadena, CA 91125, USA
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15
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Hawks AL, Bergmann A, McCraw TJ, Mason JM. UBC13-mediated template switching promotes replication stress resistance in FBH1-deficient cells. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.09.04.556280. [PMID: 37732269 PMCID: PMC10508767 DOI: 10.1101/2023.09.04.556280] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/22/2023]
Abstract
The proper resolution of DNA damage during replication is essential for genome stability. FBH1, a UvrD, helicase plays crucial roles in the DNA damage response. FBH1 promotes double strand break formation and signaling in response to prolonged replication stress to initiate apoptosis. Human FBH1 regulates RAD51 to inhibit homologous recombination. A previous study suggested that mis-regulation of RAD51 may contribute to replication stress resistance in FBH1-deficient cells, but the underlying mechanism remains unknown. Here, we provide direct evidence that RAD51 promotes replication stress resistance in FBH1-deficient cells. We demonstrate inhibition of RAD51 using the small molecule, B02, partially rescues double strand break signaling in FBH1-deficient cells. We show that inhibition of only the strand exchange activity of RAD51 rescues double strand break signaling in FBH1 knockout cells. Finally, we show that depletion of UBC13, a E2 protein that promotes RAD51-dependent template switching, rescues double strand break formation and signaling sensitizing FBH1-deficient cells to replication stress. Our results suggest FBH1 regulates template switching to promote replication stress sensitivity.
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Affiliation(s)
- Alexandra L. Hawks
- Department of Genetics and Biochemistry, Clemson University, Clemson University
| | - Amy Bergmann
- Department of Genetics and Biochemistry, Clemson University, Clemson University
| | - Tyler J. McCraw
- Department of Genetics and Biochemistry, Clemson University, Clemson University
| | - Jennifer M. Mason
- Department of Genetics and Biochemistry, Clemson University, Clemson University
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16
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Liu W, Saito Y, Jackson J, Bhowmick R, Kanemaki MT, Vindigni A, Cortez D. RAD51 bypasses the CMG helicase to promote replication fork reversal. Science 2023; 380:382-387. [PMID: 37104614 PMCID: PMC10302453 DOI: 10.1126/science.add7328] [Citation(s) in RCA: 19] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Accepted: 03/25/2023] [Indexed: 04/29/2023]
Abstract
Replication fork reversal safeguards genome integrity as a replication stress response. DNA translocases and the RAD51 recombinase catalyze reversal. However, it remains unknown why RAD51 is required and what happens to the replication machinery during reversal. We find that RAD51 uses its strand exchange activity to circumvent the replicative helicase, which remains bound to the stalled fork. RAD51 is not required for fork reversal if the helicase is unloaded. Thus, we propose that RAD51 creates a parental DNA duplex behind the helicase that is used as a substrate by the DNA translocases for branch migration to create a reversed fork structure. Our data explain how fork reversal happens while maintaining the helicase in a position poised to restart DNA synthesis and complete genome duplication.
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Affiliation(s)
- Wenpeng Liu
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN, 37237 USA
| | - Yuichiro Saito
- Department of Chromosome Science, National Institute of Genetics, Research Organization of Information and Systems (ROIS), Yata 1111, Mishima, Shizuoka, 411-8540, Japan
| | - Jessica Jackson
- Division of Oncology, Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Rahul Bhowmick
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN, 37237 USA
| | - Masato T. Kanemaki
- Division of Oncology, Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110, USA
- Department of Genetics, The Graduate University for Advanced Studies (SOKENDAI), Yata 1111, Mishima, Shizuoka, 411-8540, Japan
- Department of Biological Science, The University of Tokyo, Tokyo, 113-0033, Japan
| | - Alessandro Vindigni
- Division of Oncology, Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - David Cortez
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN, 37237 USA
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17
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Carnie CJ, Armstrong L, Sebesta M, Ariza A, Wang X, Graham E, Zhu K, Ahel D. ERCC6L2 mitigates replication stress and promotes centromere stability. Cell Rep 2023; 42:112329. [PMID: 37014751 DOI: 10.1016/j.celrep.2023.112329] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Revised: 01/26/2023] [Accepted: 03/20/2023] [Indexed: 04/05/2023] Open
Abstract
Structurally complex genomic regions, such as centromeres, are inherently difficult to duplicate. The mechanism behind centromere inheritance is not well understood, and one of the key questions relates to the reassembly of centromeric chromatin following DNA replication. Here, we define ERCC6L2 as a key regulator of this process. ERCC6L2 accumulates at centromeres and promotes deposition of core centromeric factors. Interestingly, ERCC6L2-/- cells show unrestrained replication of centromeric DNA, likely caused by the erosion of centromeric chromatin. Beyond centromeres, ERCC6L2 facilitates replication at genomic repeats and non-canonical DNA structures. Notably, ERCC6L2 interacts with the DNA-clamp PCNA through an atypical peptide, presented here in a co-crystal structure. Finally, ERCC6L2 also restricts DNA end resection, acting independently of the 53BP1-REV7-Shieldin complex. We propose a mechanistic model, which reconciles seemingly distinct functions of ERCC6L2 in DNA repair and DNA replication. These findings provide a molecular context for studies linking ERCC6L2 to human disease.
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Affiliation(s)
| | - Lucy Armstrong
- Sir William Dunn School of Pathology, University of Oxford, Oxford OX1 3RE, UK
| | - Marek Sebesta
- Sir William Dunn School of Pathology, University of Oxford, Oxford OX1 3RE, UK
| | - Antonio Ariza
- Sir William Dunn School of Pathology, University of Oxford, Oxford OX1 3RE, UK
| | - Xiaomeng Wang
- Sir William Dunn School of Pathology, University of Oxford, Oxford OX1 3RE, UK
| | - Emily Graham
- Sir William Dunn School of Pathology, University of Oxford, Oxford OX1 3RE, UK
| | - Kang Zhu
- Sir William Dunn School of Pathology, University of Oxford, Oxford OX1 3RE, UK
| | - Dragana Ahel
- Sir William Dunn School of Pathology, University of Oxford, Oxford OX1 3RE, UK.
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18
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RNA:DNA hybrids from Okazaki fragments contribute to establish the Ku-mediated barrier to replication-fork degradation. Mol Cell 2023; 83:1061-1074.e6. [PMID: 36868227 DOI: 10.1016/j.molcel.2023.02.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Revised: 12/09/2022] [Accepted: 02/04/2023] [Indexed: 03/05/2023]
Abstract
Nonhomologous end-joining (NHEJ) factors act in replication-fork protection, restart, and repair. Here, we identified a mechanism related to RNA:DNA hybrids to establish the NHEJ factor Ku-mediated barrier to nascent strand degradation in fission yeast. RNase H activities promote nascent strand degradation and replication restart, with a prominent role of RNase H2 in processing RNA:DNA hybrids to overcome the Ku barrier to nascent strand degradation. RNase H2 cooperates with the MRN-Ctp1 axis to sustain cell resistance to replication stress in a Ku-dependent manner. Mechanistically, the need of RNaseH2 in nascent strand degradation requires the primase activity that allows establishing the Ku barrier to Exo1, whereas impairing Okazaki fragment maturation reinforces the Ku barrier. Finally, replication stress induces Ku foci in a primase-dependent manner and favors Ku binding to RNA:DNA hybrids. We propose a function for the RNA:DNA hybrid originating from Okazaki fragments in controlling the Ku barrier specifying nuclease requirement to engage fork resection.
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19
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Herrera LR, McGlynn K, Gibbs ZA, Davis AJ, Whitehurst AW. The Cancer Testes Antigen, HORMAD1, is a Tumor-Specific Replication Fork Protection Factor. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.01.31.526348. [PMID: 36778501 PMCID: PMC9915569 DOI: 10.1101/2023.01.31.526348] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Tumors frequently activate the expression of genes that are only otherwise required for meiosis. HORMAD1, which is essential for meiotic recombination in multiple species, is expressed in over 50% of human lung adenocarcinoma cells (LUAD). We previously found that HORMAD1 promotes DNA double strand break (DSB) repair in LUAD. Here, we report that HORMAD1 takes on an additional role in protecting genomic integrity. Specifically, we find HORMAD1 is critical for protecting stalled DNA replication forks in LUAD. Loss of HORMAD1 leads to nascent DNA degradation, an event which is mediated by the MRE11-DNA2-BLM pathway. Moreover, following exogenous induction of DNA replication stress, HORMAD1 deleted cells accumulate single stranded DNA (ssDNA). We find that these phenotypes are the result of a lack of RAD51 and BRCA2 loading onto stalled replication forks. Ultimately, loss of HORMAD1 leads to increased DSBs and chromosomal aberrations in response to replication stress. Collectively, our data support a model where HORMAD1 expression is selected to mitigate DNA replication stress, which would otherwise induce deleterious genomic instability.
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20
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Kavlashvili T, Liu W, Mohamed TM, Cortez D, Dewar JM. Replication fork uncoupling causes nascent strand degradation and fork reversal. Nat Struct Mol Biol 2023; 30:115-124. [PMID: 36593312 PMCID: PMC9868089 DOI: 10.1038/s41594-022-00871-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Accepted: 10/14/2022] [Indexed: 01/03/2023]
Abstract
Genotoxins cause nascent strand degradation (NSD) and fork reversal during DNA replication. NSD and fork reversal are crucial for genome stability and are exploited by chemotherapeutic approaches. However, it is unclear how NSD and fork reversal are triggered. Additionally, the fate of the replicative helicase during these processes is unknown. We developed a biochemical approach to study synchronous, localized NSD and fork reversal using Xenopus egg extracts and validated this approach with experiments in human cells. We show that replication fork uncoupling stimulates NSD of both nascent strands and progressive conversion of uncoupled forks to reversed forks. Notably, the replicative helicase remains bound during NSD and fork reversal. Unexpectedly, NSD occurs before and after fork reversal, indicating that multiple degradation steps take place. Overall, our data show that uncoupling causes NSD and fork reversal and elucidate key events that precede fork reversal.
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Affiliation(s)
- Tamar Kavlashvili
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Wenpeng Liu
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Taha M Mohamed
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - David Cortez
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - James M Dewar
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN, USA.
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21
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Temporal phosphoproteomics reveals WEE1-dependent control of 53BP1 pathway. iScience 2022; 26:105806. [PMID: 36632060 PMCID: PMC9827073 DOI: 10.1016/j.isci.2022.105806] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2022] [Revised: 08/29/2022] [Accepted: 12/09/2022] [Indexed: 12/15/2022] Open
Abstract
Wee1-like protein kinase (WEE1) restrains activities of cyclin-dependent kinases (CDKs) in S and G2 phase. Inhibition of WEE1 evokes drastic increase in CDK activity, which perturbs replication dynamics and compromises cell cycle checkpoints. Notably, WEE1 inhibitors such as adavosertib are tested in cancer treatment trials; however, WEE1-regulated phosphoproteomes and their dynamics have not been systematically investigated. In this study, we identified acute time-resolved alterations in the cellular phosphoproteome following WEE1 inhibition with adavosertib. These treatments acutely elevated CDK activities with distinct phosphorylation dynamics revealing more than 600 potential uncharacterized CDK sites. Moreover, we identified a major role for WEE1 in controlling CDK-dependent phosphorylation of multiple clustered sites in the key DNA repair factors MDC1, 53BP1, and RIF1. Functional analysis revealed that WEE1 fine-tunes CDK activities to permit recruitment of 53BP1 to chromatin. Thus, our findings uncover WEE1-controlled targets and pathways with translational potential for the clinical application of WEE1 inhibitors.
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22
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Li X, Wang L, Liu X, Zheng Z, Kong D. Cellular regulation and stability of DNA replication forks in eukaryotic cells. DNA Repair (Amst) 2022; 120:103418. [DOI: 10.1016/j.dnarep.2022.103418] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2022] [Revised: 10/03/2022] [Accepted: 10/07/2022] [Indexed: 11/03/2022]
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23
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Zhu C, Iwase M, Li Z, Wang F, Quinet A, Vindigni A, Shao J. Profilin-1 regulates DNA replication forks in a context-dependent fashion by interacting with SNF2H and BOD1L. Nat Commun 2022; 13:6531. [PMID: 36319634 PMCID: PMC9626489 DOI: 10.1038/s41467-022-34310-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2022] [Accepted: 10/21/2022] [Indexed: 12/04/2022] Open
Abstract
DNA replication forks are tightly controlled by a large protein network consisting of well-known core regulators and many accessory factors which remain functionally undefined. In this study, we report previously unknown nuclear functions of the actin-binding factor profilin-1 (PFN1) in DNA replication, which occur in a context-dependent fashion and require its binding to poly-L-proline (PLP)-containing proteins instead of actin. In unperturbed cells, PFN1 increases DNA replication initiation and accelerates fork progression by binding and stimulating the PLP-containing nucleosome remodeler SNF2H. Under replication stress, PFN1/SNF2H increases fork stalling and functionally collaborates with fork reversal enzymes to enable the over-resection of unprotected forks. In addition, PFN1 binds and functionally attenuates the PLP-containing fork protector BODL1 to increase the resection of a subset of stressed forks. Accordingly, raising nuclear PFN1 level decreases genome stability and cell survival during replication stress. Thus, PFN1 is a multi-functional regulator of DNA replication with exploitable anticancer potential.
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Affiliation(s)
- Cuige Zhu
- Divison of Oncology, Department of Medicine, Washington University School of Medicine, St. Louis, MO, USA
| | - Mari Iwase
- Divison of Oncology, Department of Medicine, Washington University School of Medicine, St. Louis, MO, USA
| | - Ziqian Li
- Divison of Oncology, Department of Medicine, Washington University School of Medicine, St. Louis, MO, USA
- Department of Microbial and Biochemical Pharmacy, School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou, China
| | - Faliang Wang
- Divison of Oncology, Department of Medicine, Washington University School of Medicine, St. Louis, MO, USA
| | - Annabel Quinet
- Divison of Oncology, Department of Medicine, Washington University School of Medicine, St. Louis, MO, USA
- UMR Genetic Stability Stem Cells and Radiation, University of Paris and University of Paris-Saclay, INSERM, iRCM/IBFJ CEA, Fontenay-aux-Roses, France
| | - Alessandro Vindigni
- Divison of Oncology, Department of Medicine, Washington University School of Medicine, St. Louis, MO, USA
- Siteman Cancer Center, Washington University School of Medicine, St. Louis, MO, 63110, USA
| | - Jieya Shao
- Divison of Oncology, Department of Medicine, Washington University School of Medicine, St. Louis, MO, USA.
- Siteman Cancer Center, Washington University School of Medicine, St. Louis, MO, 63110, USA.
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24
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Zhang J, Chan DW, Lin SY. Exploiting DNA Replication Stress as a Therapeutic Strategy for Breast Cancer. Biomedicines 2022; 10:2775. [PMID: 36359297 PMCID: PMC9687274 DOI: 10.3390/biomedicines10112775] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2022] [Revised: 10/19/2022] [Accepted: 10/27/2022] [Indexed: 09/19/2023] Open
Abstract
Proliferating cells rely on DNA replication to ensure accurate genome duplication. Cancer cells, including breast cancer cells, exhibit elevated replication stress (RS) due to the uncontrolled oncogenic activation, loss of key tumor suppressors, and defects in the DNA repair machinery. This intrinsic vulnerability provides a great opportunity for therapeutic exploitation. An increasing number of drug candidates targeting RS in breast cancer are demonstrating promising efficacy in preclinical and early clinical trials. However, unresolved challenges lie in balancing the toxicity of these drugs while maintaining clinical efficacy. Furthermore, biomarkers of RS are urgently required to guide patient selection. In this review, we introduce the concept of targeting RS, detail the current therapies that target RS, and highlight the integration of RS with immunotherapies for breast cancer treatment. Additionally, we discuss the potential biomarkers to optimizing the efficacy of these therapies. Together, the continuous advances in our knowledge of targeting RS would benefit more patients with breast cancer.
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Affiliation(s)
- Jing Zhang
- Department of Systems Biology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | | | - Shiaw-Yih Lin
- Department of Systems Biology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
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25
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Thakar T, Dhoonmoon A, Straka J, Schleicher EM, Nicolae CM, Moldovan GL. Lagging strand gap suppression connects BRCA-mediated fork protection to nucleosome assembly through PCNA-dependent CAF-1 recycling. Nat Commun 2022; 13:5323. [PMID: 36085347 PMCID: PMC9463168 DOI: 10.1038/s41467-022-33028-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Accepted: 08/29/2022] [Indexed: 11/17/2022] Open
Abstract
The inability to protect stalled replication forks from nucleolytic degradation drives genome instability and underlies chemosensitivity in BRCA-deficient tumors. An emerging hallmark of BRCA-deficiency is the inability to suppress replication-associated single-stranded DNA (ssDNA) gaps. Here, we report that lagging strand ssDNA gaps interfere with the ASF1-CAF-1 nucleosome assembly pathway, and drive fork degradation in BRCA-deficient cells. We show that CAF-1 function at replication forks is lost in BRCA-deficient cells, due to defects in its recycling during replication stress. This CAF-1 recycling defect is caused by lagging strand gaps which preclude PCNA unloading, causing sequestration of PCNA-CAF-1 complexes on chromatin. Importantly, correcting PCNA unloading defects in BRCA-deficient cells restores CAF-1-dependent fork stability. We further show that the activation of a HIRA-dependent compensatory histone deposition pathway restores fork stability to BRCA-deficient cells. We thus define lagging strand gap suppression and nucleosome assembly as critical enablers of BRCA-mediated fork stability. Efficient DNA replication is crucial for genome stability. Here, Thakar et al. report that accumulation of lagging strand ssDNA gaps during replication interferes with nucleosome assembly and drives replication fork degradation in BRCA-deficient cells.
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Affiliation(s)
- Tanay Thakar
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University College of Medicine, Hershey, PA, 17033, USA
| | - Ashna Dhoonmoon
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University College of Medicine, Hershey, PA, 17033, USA
| | - Joshua Straka
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University College of Medicine, Hershey, PA, 17033, USA
| | - Emily M Schleicher
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University College of Medicine, Hershey, PA, 17033, USA
| | - Claudia M Nicolae
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University College of Medicine, Hershey, PA, 17033, USA
| | - George-Lucian Moldovan
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University College of Medicine, Hershey, PA, 17033, USA.
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26
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Paniagua I, Tayeh Z, Falcone M, Hernández Pérez S, Cerutti A, Jacobs JJL. MAD2L2 promotes replication fork protection and recovery in a shieldin-independent and REV3L-dependent manner. Nat Commun 2022; 13:5167. [PMID: 36075897 PMCID: PMC9458726 DOI: 10.1038/s41467-022-32861-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Accepted: 08/18/2022] [Indexed: 11/10/2022] Open
Abstract
Protection of stalled replication forks is essential to prevent genome instability, a major driving force of tumorigenesis. Several key regulators of DNA double-stranded break (DSB) repair, including 53BP1 and RIF1, have been implicated in fork protection. MAD2L2, also known as REV7, plays an important role downstream of 53BP1/RIF1 by counteracting resection at DSBs in the recently discovered shieldin complex. The ability to bind and counteract resection at exposed DNA ends at DSBs makes MAD2L2/shieldin a prime candidate for also suppressing nucleolytic processing at stalled replication forks. However, the function of MAD2L2/shieldin outside of DNA repair is unknown. Here we address this by using genetic and single-molecule analyses and find that MAD2L2 is required for protecting and restarting stalled replication forks. MAD2L2 loss leads to uncontrolled MRE11-dependent resection of stalled forks and single-stranded DNA accumulation, which causes irreparable genomic damage. Unexpectedly, MAD2L2 limits resection at stalled forks independently of shieldin, since fork protection remained unaffected by shieldin loss. Instead, MAD2L2 cooperates with the DNA polymerases REV3L and REV1 to promote fork stability. Thus, MAD2L2 suppresses aberrant nucleolytic processing both at DSBs and stalled replication forks by differentially engaging shieldin and REV1/REV3L, respectively. MAD2L2 – as a member of the shieldin complex - counteracts resection during DNA repair. Here the authors demonstrate that MAD2L2 protects stalled replication forks from excessive resection, in a shieldin-independent and REV3L-dependent manner.
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Affiliation(s)
- Inés Paniagua
- Division of Oncogenomics, The Netherlands Cancer Institute, Plesmanlaan 121, 1066 CX, Amsterdam, The Netherlands
| | - Zainab Tayeh
- Division of Oncogenomics, The Netherlands Cancer Institute, Plesmanlaan 121, 1066 CX, Amsterdam, The Netherlands
| | - Mattia Falcone
- Division of Oncogenomics, The Netherlands Cancer Institute, Plesmanlaan 121, 1066 CX, Amsterdam, The Netherlands
| | - Santiago Hernández Pérez
- Division of Oncogenomics, The Netherlands Cancer Institute, Plesmanlaan 121, 1066 CX, Amsterdam, The Netherlands
| | - Aurora Cerutti
- Division of Oncogenomics, The Netherlands Cancer Institute, Plesmanlaan 121, 1066 CX, Amsterdam, The Netherlands
| | - Jacqueline J L Jacobs
- Division of Oncogenomics, The Netherlands Cancer Institute, Plesmanlaan 121, 1066 CX, Amsterdam, The Netherlands.
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27
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Feu S, Unzueta F, Ercilla A, Pérez-Venteo A, Jaumot M, Agell N. RAD51 is a druggable target that sustains replication fork progression upon DNA replication stress. PLoS One 2022; 17:e0266645. [PMID: 35969531 PMCID: PMC9377619 DOI: 10.1371/journal.pone.0266645] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2022] [Accepted: 07/19/2022] [Indexed: 11/18/2022] Open
Abstract
Solving the problems that replication forks encounter when synthesizing DNA is essential to prevent genomic instability. Besides their role in DNA repair in the G2 phase, several homologous recombination proteins, specifically RAD51, have prominent roles in the S phase. Using different cellular models, RAD51 has been shown not only to be present at ongoing and arrested replication forks but also to be involved in nascent DNA protection and replication fork restart. Through pharmacological inhibition, here we study the specific role of RAD51 in the S phase. RAD51 inhibition in non-transformed cell lines did not have a significant effect on replication fork progression under non-perturbed conditions, but when the same cells were subjected to replication stress, RAD51 became necessary to maintain replication fork progression. Notably, the inhibition or depletion of RAD51 did not compromise fork integrity when subjected to hydroxyurea treatment. RAD51 inhibition also did not decrease the ability to restart, but rather compromised fork progression during reinitiation. In agreement with the presence of basal replication stress in human colorectal cancer cells, RAD51 inhibition reduced replication fork speed in these cells and increased γH2Ax foci under control conditions. These alterations could have resulted from the reduced association of DNA polymerase α to chromatin, as observed when inhibiting RAD51. It may be possible to exploit the differential dependence of non-transformed cells versus colorectal cancer cells on RAD51 activity under basal conditions to design new therapies that specifically target cancer cells.
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Affiliation(s)
- Sonia Feu
- Dept. Biomedicina, Universitat de Barcelona, Barcelona, Spain
- Institut d’Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain
| | - Fernando Unzueta
- Dept. Biomedicina, Universitat de Barcelona, Barcelona, Spain
- Institut d’Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain
| | - Amaia Ercilla
- CIC bioGUNE, Basque Research and Technology Alliance (BRTA), Derio, Spain
| | | | - Montserrat Jaumot
- Dept. Biomedicina, Universitat de Barcelona, Barcelona, Spain
- Institut d’Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain
| | - Neus Agell
- Dept. Biomedicina, Universitat de Barcelona, Barcelona, Spain
- Institut d’Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain
- * E-mail:
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28
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Nickoloff JA. Targeting Replication Stress Response Pathways to Enhance Genotoxic Chemo- and Radiotherapy. MOLECULES (BASEL, SWITZERLAND) 2022; 27:molecules27154736. [PMID: 35897913 PMCID: PMC9330692 DOI: 10.3390/molecules27154736] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/01/2022] [Revised: 07/20/2022] [Accepted: 07/22/2022] [Indexed: 12/12/2022]
Abstract
Proliferating cells regularly experience replication stress caused by spontaneous DNA damage that results from endogenous reactive oxygen species (ROS), DNA sequences that can assume secondary and tertiary structures, and collisions between opposing transcription and replication machineries. Cancer cells face additional replication stress, including oncogenic stress that results from the dysregulation of fork progression and origin firing, and from DNA damage induced by radiotherapy and most cancer chemotherapeutic agents. Cells respond to such stress by activating a complex network of sensor, signaling and effector pathways that protect genome integrity. These responses include slowing or stopping active replication forks, protecting stalled replication forks from collapse, preventing late origin replication firing, stimulating DNA repair pathways that promote the repair and restart of stalled or collapsed replication forks, and activating dormant origins to rescue adjacent stressed forks. Currently, most cancer patients are treated with genotoxic chemotherapeutics and/or ionizing radiation, and cancer cells can gain resistance to the resulting replication stress by activating pro-survival replication stress pathways. Thus, there has been substantial effort to develop small molecule inhibitors of key replication stress proteins to enhance tumor cell killing by these agents. Replication stress targets include ATR, the master kinase that regulates both normal replication and replication stress responses; the downstream signaling kinase Chk1; nucleases that process stressed replication forks (MUS81, EEPD1, Metnase); the homologous recombination catalyst RAD51; and other factors including ATM, DNA-PKcs, and PARP1. This review provides an overview of replication stress response pathways and discusses recent pre-clinical studies and clinical trials aimed at improving cancer therapy by targeting replication stress response factors.
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Affiliation(s)
- Jac A Nickoloff
- Department of Environmental and Radiological Health Sciences, Colorado State University, Fort Collins, CO 80523, USA
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29
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Yang Z, Lemacon DS, Li S, Cheruiyot A, Kong L, Tan K, Cheng C, Turkay E, He D, You Z. Context-dependent pro- and anti-resection roles of ZKSCAN3 in the regulation of fork processing during replication stress. J Biol Chem 2022; 298:102215. [PMID: 35779634 PMCID: PMC9352557 DOI: 10.1016/j.jbc.2022.102215] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2022] [Revised: 06/20/2022] [Accepted: 06/21/2022] [Indexed: 11/26/2022] Open
Abstract
Uncontrolled resection of replication forks under stress can cause genomic instability and influence cancer formation. Extensive fork resection has also been implicated in the chemosensitivity of “BReast CAncer gene” BRCA-deficient cancers. However, how fork resection is controlled in different genetic contexts and how it affects chromosomal stability and cell survival remains incompletely understood. Here, we report a novel function of the transcription repressor ZKSCAN3 in fork protection and chromosomal stability maintenance under replication stress. We show disruption of ZKSCAN3 function causes excessive resection of replication forks by the exonuclease Exo1 and homologous DNA recombination/repair protein Mre11 following fork reversal. Interestingly, in BRCA1-deficient cells, we found ZKSCAN3 actually promotes fork resection upon replication stress. We demonstrate these anti- and pro-resection roles of ZKSCAN3, consisting of a SCAN box, Kruppel-associated box, and zinc finger domain, are mediated by its SCAN box domain and do not require the Kruppel-associated box or zinc finger domains, suggesting that the transcriptional function of ZKSCAN3 is not involved. Furthermore, despite the severe impact on fork structure and chromosomal stability, depletion of ZKSCAN3 did not affect the short-term survival of BRCA1-proficient or BRCA1-deficient cells after treatment with cancer drugs hydroxyurea, PARPi, or cisplatin. Our findings reveal a unique relationship between ZKSCAN3 and BRCA1 in fork protection and add to our understanding of the relationships between replication fork protection, chromosomal instability, and chemosensitivity.
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Affiliation(s)
- Zheng Yang
- Department of Urology, First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi 710061 China; Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Delphine Sangotokun Lemacon
- Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Shan Li
- Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Abigael Cheruiyot
- Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Lingzhen Kong
- Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Ke Tan
- Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Chen Cheng
- Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Ecenur Turkay
- Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Dalin He
- Department of Urology, First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi 710061 China
| | - Zhongsheng You
- Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, MO 63110, USA.
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30
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Selemenakis P, Sharma N, Uhrig ME, Katz J, Kwon Y, Sung P, Wiese C. RAD51AP1 and RAD54L Can Underpin Two Distinct RAD51-Dependent Routes of DNA Damage Repair via Homologous Recombination. Front Cell Dev Biol 2022; 10:866601. [PMID: 35652094 PMCID: PMC9149245 DOI: 10.3389/fcell.2022.866601] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Accepted: 04/20/2022] [Indexed: 11/17/2022] Open
Abstract
Homologous recombination DNA repair (HR) is a complex DNA damage repair pathway and an attractive target of inhibition in anti-cancer therapy. To help guide the development of efficient HR inhibitors, it is critical to identify compensatory HR sub-pathways. In this study, we describe a novel synthetic interaction between RAD51AP1 and RAD54L, two structurally unrelated proteins that function downstream of the RAD51 recombinase in HR. We show that concomitant deletion of RAD51AP1 and RAD54L further sensitizes human cancer cell lines to treatment with olaparib, a Poly (adenosine 5′-diphosphate-ribose) polymerase inhibitor, to the DNA inter-strand crosslinking agent mitomycin C, and to hydroxyurea, which induces DNA replication stress. We also show that the RAD54L paralog RAD54B compensates for RAD54L deficiency, although, surprisingly, less extensively than RAD51AP1. These results, for the first time, delineate RAD51AP1- and RAD54L-dependent sub-pathways and will guide the development of inhibitors that target HR stimulators of strand invasion.
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Affiliation(s)
- Platon Selemenakis
- Department of Environmental and Radiological Health Sciences, Colorado State University, Fort Collins, CO, United States.,Cell and Molecular Biology Graduate Program, Colorado State University, Fort Collins, CO, United States
| | - Neelam Sharma
- Department of Environmental and Radiological Health Sciences, Colorado State University, Fort Collins, CO, United States
| | - Mollie E Uhrig
- Department of Environmental and Radiological Health Sciences, Colorado State University, Fort Collins, CO, United States
| | - Jeffrey Katz
- Department of Biochemistry and Structural Biology, University of Texas Health Science Center at San Antonio, San Antonio, TX, United States
| | - Youngho Kwon
- Department of Biochemistry and Structural Biology, University of Texas Health Science Center at San Antonio, San Antonio, TX, United States
| | - Patrick Sung
- Department of Biochemistry and Structural Biology, University of Texas Health Science Center at San Antonio, San Antonio, TX, United States
| | - Claudia Wiese
- Department of Environmental and Radiological Health Sciences, Colorado State University, Fort Collins, CO, United States
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Abstract
Although hematopoietic stem cells (HSCs) in the bone marrow are in a state of quiescence, they harbor the self-renewal capacity and the pluripotency to differentiate into mature blood cells when needed, which is key to maintain hematopoietic homeostasis. Importantly, HSCs are characterized by their long lifespan ( e. g., up to 60 months for mice), display characteristics of aging, and are vulnerable to various endogenous and exogenous genotoxic stresses. Generally, DNA damage in HSCs is endogenous, which is typically induced by reactive oxygen species (ROS), aldehydes, and replication stress. Mammalian cells have evolved a complex and efficient DNA repair system to cope with various DNA lesions to maintain genomic stability. The repair machinery for DNA damage in HSCs has its own characteristics. For instance, the Fanconi anemia (FA)/BRCA pathway is particularly important for the hematopoietic system, as it can limit the damage caused by DNA inter-strand crosslinks, oxidative stress, and replication stress to HSCs to prevent FA occurrence. In addition, HSCs prefer to utilize the classical non-homologous end-joining pathway, which is essential for the V(D)J rearrangement in developing lymphocytes and is involved in double-strand break repair to maintain genomic stability in the long-term quiescent state. In contrast, the base excision repair pathway is less involved in the hematopoietic system. In this review, we summarize the impact of various types of DNA damage on HSC function and review our knowledge of the corresponding repair mechanisms and related human genetic diseases.
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32
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Zhang J, Chen M, Pang Y, Cheng M, Huang B, Xu S, Liu M, Lian H, Zhong C. Flap endonuclease 1 and DNA-PKcs synergistically participate in stabilizing replication fork to encounter replication stress in glioma cells. JOURNAL OF EXPERIMENTAL & CLINICAL CANCER RESEARCH : CR 2022; 41:140. [PMID: 35414100 PMCID: PMC9006432 DOI: 10.1186/s13046-022-02334-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/17/2022] [Accepted: 03/17/2022] [Indexed: 12/15/2022]
Abstract
Background Selectively utilizing alternative mechanisms to repair damaged DNA in essential factors deficient cancer facilitates tumor genetic evolution and contributes to treatment resistance. Synthetic lethality strategies provide a novel scenario to anticancer therapy with DNA repair protein mutation, such as glioma with DNA-PKcs-deficiency, a core factor crucial for non-homologous end joining (NHEJ) mediated DNA damage repair. Nevertheless, the clinical significance and molecular mechanisms of synthetic lethality function by interfering tumor DNA replication remain largely unexplored. Methods Cancer clinic treatment resistance-related replication core factors were identified through bioinformatics analysis and RNA-sequencing and verified in clinical specimens by immunoblotting and in situ Proximity Ligation Analysis (PLA). Then, in vitro and in vivo experiments, including visible single molecular tracking system were performed to determine functional roles, the molecular mechanisms and clinical significance of synthetic lethality on glioma tumors. Results Hyperactive DNA replication and regulator Flap endonuclease 1 (FEN1) provides high efficiency DNA double strand breaks (DSB) repair abilities preventing replication forks collapse during DNA replication which facilitate adaptation to selective pressures. DNA-PKcs deficient glioma cells are highly dependent on FEN1/BRCA1/RAD51 to survival and counteract replication stress. FEN1 protects perturbed forks from erroneous over-resection by MRE11 through regulating of BRCA1-RAD51 and WRN helicase, uncovering an essential genetic interaction between FEN1 and DNA-PKcs in mitigating replication-stress induced tumor genomic instability. Therapeutically, genetic depletion or molecular inhibition of FEN1 and DNA-PKcs perturb glioma progression. Conclusions Our findings highlight an unanticipated synthetic interaction between FEN1/BRCA1/RAD51 and DNA-PKcs when dysfunction leads to incompatible with cell survival under conditions of interrupted replication progression by disrupting addictive alternative tumor evolution and demonstrate the applicability of combined FEN1 and DNA-PKcs targeting in the treatment of glioma. Supplementary Information The online version contains supplementary material available at 10.1186/s13046-022-02334-0.
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Affiliation(s)
- Jing Zhang
- Department of Neurosurgery, Shanghai East Hospital, Tongji University School of Medicine, 150 Jimo Road, Shanghai, 200120, China. .,Institute for Advanced Study, Tongji University, 1239 Siping Road, Shanghai, 200092, China.
| | - Mu Chen
- Department of Neurosurgery, Shanghai East Hospital, Tongji University School of Medicine, 150 Jimo Road, Shanghai, 200120, China
| | - Ying Pang
- Department of Neurosurgery, Shanghai East Hospital, Tongji University School of Medicine, 150 Jimo Road, Shanghai, 200120, China
| | - Meng Cheng
- Department of Neurosurgery, Shanghai East Hospital, Tongji University School of Medicine, 150 Jimo Road, Shanghai, 200120, China
| | - Bingsong Huang
- Department of Neurosurgery, Shanghai East Hospital, Tongji University School of Medicine, 150 Jimo Road, Shanghai, 200120, China
| | - Siyi Xu
- Department of Neurosurgery, Shanghai East Hospital, Tongji University School of Medicine, 150 Jimo Road, Shanghai, 200120, China
| | - Min Liu
- Department of Neurosurgery, Shanghai East Hospital, Tongji University School of Medicine, 150 Jimo Road, Shanghai, 200120, China
| | - Hao Lian
- Department of Neurosurgery, Shanghai East Hospital, Tongji University School of Medicine, 150 Jimo Road, Shanghai, 200120, China
| | - Chunlong Zhong
- Department of Neurosurgery, Shanghai East Hospital, Tongji University School of Medicine, 150 Jimo Road, Shanghai, 200120, China.
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33
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Mohamed T, Adolph MB, Cortez D. Oligomerization of DNA replication regulatory protein RADX is essential to maintain replication fork stability. J Biol Chem 2022; 298:101672. [PMID: 35120927 PMCID: PMC8902620 DOI: 10.1016/j.jbc.2022.101672] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2021] [Revised: 01/25/2022] [Accepted: 01/27/2022] [Indexed: 11/23/2022] Open
Abstract
Genome integrity requires complete and accurate DNA replication once per cell division cycle. Replication stress poses obstacles to this process that must be overcome to prevent replication fork collapse. An important regulator of replication fork stability is the RAD51 protein, which promotes replication fork reversal and protects nascent DNA strands from nuclease-mediated degradation. Many regulatory proteins control these RAD51 activities, including RADX, which binds both ssDNA and RAD51 at replication forks to ensure that fork reversal is confined to stalled forks. Many ssDNA-binding proteins function as hetero- or homo-oligomers. In this study, we addressed whether this is also the case for RADX. Using biochemical and genetic approaches, we found that RADX acts as a homo-oligomer to control replication fork stability. RADX oligomerizes using at least two different interaction surfaces, including one mapped to a C-terminal region. We demonstrate that mutations in this region prevent oligomerization and prevent RADX function in cells, and that addition of a heterologous dimerization domain to the oligomerization mutants restored their ability to regulate replication. Taken together, our results demonstrate that like many ssDNA-binding proteins, oligomerization is essential for RADX-mediated regulation of genome stability.
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Affiliation(s)
- Taha Mohamed
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Madison B Adolph
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - David Cortez
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN, USA.
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34
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Temporally distinct post-replicative repair mechanisms fill PRIMPOL-dependent ssDNA gaps in human cells. Mol Cell 2021; 81:4026-4040.e8. [PMID: 34624216 DOI: 10.1016/j.molcel.2021.09.013] [Citation(s) in RCA: 78] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2021] [Revised: 07/20/2021] [Accepted: 09/10/2021] [Indexed: 12/11/2022]
Abstract
PRIMPOL repriming allows DNA replication to skip DNA lesions, leading to ssDNA gaps. These gaps must be filled to preserve genome stability. Using a DNA fiber approach to directly monitor gap filling, we studied the post-replicative mechanisms that fill the ssDNA gaps generated in cisplatin-treated cells upon increased PRIMPOL expression or when replication fork reversal is defective because of SMARCAL1 inactivation or PARP inhibition. We found that a mechanism dependent on the E3 ubiquitin ligase RAD18, PCNA monoubiquitination, and the REV1 and POLζ translesion synthesis polymerases promotes gap filling in G2. The E2-conjugating enzyme UBC13, the RAD51 recombinase, and REV1-POLζ are instead responsible for gap filling in S, suggesting that temporally distinct pathways of gap filling operate throughout the cell cycle. Furthermore, we found that BRCA1 and BRCA2 promote gap filling by limiting MRE11 activity and that simultaneously targeting fork reversal and gap filling enhances chemosensitivity in BRCA-deficient cells.
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Morati F, Modesti M. Insights into the control of RAD51 nucleoprotein filament dynamics from single-molecule studies. Curr Opin Genet Dev 2021; 71:182-187. [PMID: 34571340 DOI: 10.1016/j.gde.2021.09.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2021] [Revised: 09/05/2021] [Accepted: 09/10/2021] [Indexed: 11/26/2022]
Abstract
Genomic integrity depends on the RecA/RAD51 protein family. Discovered over five decades ago with the founder bacterial RecA protein, eukaryotic RAD51 is an ATP-dependent DNA strand transferase implicated in DNA double-strand break and single-strand gap repair, and in dealing with stressed DNA replication forks. RAD51 assembles as a nucleoprotein filament around single-stranded DNA to promote homology recognition in a duplex DNA and subsequent strand exchange. While the intrinsic dynamics of the RAD51 nucleoprotein filament has been extensively studied, a plethora of accessory factors control its dynamics. Understanding how modulators control filament dynamics is at the heart of current research efforts. Here, we describe recent advances in RAD51 control mechanisms obtained specifically using fluorescence-based single-molecule techniques.
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Affiliation(s)
- Florian Morati
- Cancer Research Center of Marseille, CNRS UMR7258, Inserm U1068, Institut Paoli-Calmettes, Aix-Marseille Université UM105, Marseille, France
| | - Mauro Modesti
- Cancer Research Center of Marseille, CNRS UMR7258, Inserm U1068, Institut Paoli-Calmettes, Aix-Marseille Université UM105, Marseille, France.
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Scully R, Elango R, Panday A, Willis NA. Recombination and restart at blocked replication forks. Curr Opin Genet Dev 2021; 71:154-162. [PMID: 34464818 DOI: 10.1016/j.gde.2021.08.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2021] [Revised: 07/28/2021] [Accepted: 08/06/2021] [Indexed: 01/07/2023]
Abstract
Replication fork stalling occurs when the replisome encounters a barrier to normal fork progression. Replisome stalling events are common during scheduled DNA synthesis, but vary in their severity. At one extreme, a lesion may induce only temporary pausing of a DNA polymerase; at the other, it may present a near-absolute barrier to the replicative helicase and effectively block fork progression. Many alternative pathways have evolved to respond to these different types of replication stress. Among these, the homologous recombination (HR) pathway plays an important role, protecting the stalled fork and processing it for repair. Here, we review recent advances in our understanding of how blocked replication forks in vertebrate cells can be processed for recombination and for replication restart.
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Affiliation(s)
- Ralph Scully
- Department of Medicine, Division of Hematology-Oncology and Cancer Research Institute, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA 02215, USA.
| | - Rajula Elango
- Department of Medicine, Division of Hematology-Oncology and Cancer Research Institute, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA 02215, USA
| | - Arvind Panday
- Department of Medicine, Division of Hematology-Oncology and Cancer Research Institute, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA 02215, USA
| | - Nicholas A Willis
- Department of Medicine, Division of Hematology-Oncology and Cancer Research Institute, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA 02215, USA
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37
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Replication stress: from chromatin to immunity and beyond. Curr Opin Genet Dev 2021; 71:136-142. [PMID: 34455237 DOI: 10.1016/j.gde.2021.08.004] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2021] [Revised: 08/08/2021] [Accepted: 08/12/2021] [Indexed: 12/25/2022]
Abstract
Replication stress (RS) is a hallmark of cancer cells that is associated with increased genomic instability. RS occurs when replication forks encounter obstacles along the DNA. Stalled forks are signaled by checkpoint kinases that prevent fork collapse and coordinate fork repair pathways. Fork restart also depends on chromatin remodelers to increase the accessibility of nascent chromatin to recombination and repair factors. In this review, we discuss recent findings on the causes and consequences of RS, with a focus on endogenous replication impediments and their impact on fork velocity. We also discuss recent studies on the interplay between stalled forks and innate immunity, which extends the RS response beyond cell boundaries and opens new avenues for cancer therapy.
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38
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Le HP, Heyer WD, Liu J. Guardians of the Genome: BRCA2 and Its Partners. Genes (Basel) 2021; 12:genes12081229. [PMID: 34440403 PMCID: PMC8394001 DOI: 10.3390/genes12081229] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2021] [Revised: 08/04/2021] [Accepted: 08/06/2021] [Indexed: 12/28/2022] Open
Abstract
The tumor suppressor BRCA2 functions as a central caretaker of genome stability, and individuals who carry BRCA2 mutations are predisposed to breast, ovarian, and other cancers. Recent research advanced our mechanistic understanding of BRCA2 and its various interaction partners in DNA repair, DNA replication support, and DNA double-strand break repair pathway choice. In this review, we discuss the biochemical and structural properties of BRCA2 and examine how these fundamental properties contribute to DNA repair and replication fork stabilization in living cells. We highlight selected BRCA2 binding partners and discuss their role in BRCA2-mediated homologous recombination and fork protection. Improved mechanistic understanding of how BRCA2 functions in genome stability maintenance can enable experimental evidence-based evaluation of pathogenic BRCA2 mutations and BRCA2 pseudo-revertants to support targeted therapy.
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Affiliation(s)
- Hang Phuong Le
- Department of Microbiology and Molecular Genetics, University of California, Davis, CA 95616, USA; (H.P.L.); (W.-D.H.)
| | - Wolf-Dietrich Heyer
- Department of Microbiology and Molecular Genetics, University of California, Davis, CA 95616, USA; (H.P.L.); (W.-D.H.)
- Department of Molecular and Cellular Biology, University of California, Davis, CA 95616, USA
| | - Jie Liu
- Department of Microbiology and Molecular Genetics, University of California, Davis, CA 95616, USA; (H.P.L.); (W.-D.H.)
- Correspondence: ; Tel.: +1-530-752-3016
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Ihle M, Biber S, Schroeder IS, Blattner C, Deniz M, Damia G, Gottifredi V, Wiesmüller L. Impact of the interplay between stemness features, p53 and pol iota on replication pathway choices. Nucleic Acids Res 2021; 49:7457-7475. [PMID: 34165573 PMCID: PMC8287946 DOI: 10.1093/nar/gkab526] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Revised: 06/02/2021] [Accepted: 06/09/2021] [Indexed: 12/12/2022] Open
Abstract
Using human embryonic, adult and cancer stem cells/stem cell-like cells (SCs), we demonstrate that DNA replication speed differs in SCs and their differentiated counterparts. While SCs decelerate DNA replication, differentiated cells synthesize DNA faster and accumulate DNA damage. Notably, both replication phenotypes depend on p53 and polymerase iota (POLι). By exploring protein interactions and newly synthesized DNA, we show that SCs promote complex formation of p53 and POLι at replication sites. Intriguingly, in SCs the translocase ZRANB3 is recruited to POLι and required for slow-down of DNA replication. The known role of ZRANB3 in fork reversal suggests that the p53–POLι complex mediates slow but safe bypass of replication barriers in SCs. In differentiated cells, POLι localizes more transiently to sites of DNA synthesis and no longer interacts with p53 facilitating fast POLι-dependent DNA replication. In this alternative scenario, POLι associates with the p53 target p21, which antagonizes PCNA poly-ubiquitination and, thereby potentially disfavors the recruitment of translocases. Altogether, we provide evidence for diametrically opposed DNA replication phenotypes in SCs and their differentiated counterparts putting DNA replication-based strategies in the spotlight for the creation of therapeutic opportunities targeting SCs.
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Affiliation(s)
- Michaela Ihle
- Department of Obstetrics and Gynecology, Ulm University, Ulm 89075, Germany
| | - Stephanie Biber
- Department of Obstetrics and Gynecology, Ulm University, Ulm 89075, Germany
| | - Insa S Schroeder
- Department of Biophysics, GSI Helmholtz Center for Heavy Ion Research, Darmstadt 64291, Germany
| | - Christine Blattner
- Institute for Biological and Chemical Systems - Biological Information Processing, Karlsruhe Institute of Technology, Karlsruhe 76021, Germany
| | - Miriam Deniz
- Department of Obstetrics and Gynecology, Ulm University, Ulm 89075, Germany
| | - Giovanna Damia
- Department of Oncology, Istituto di Ricerche Farmacologiche Mario Negri-IRCCS Milan, Milan 20156, Italy
| | - Vanesa Gottifredi
- Cell cycle and Genomic Stability Laboratory, Fundación Instituto Leloir, Buenos Aires C1405BWE, Argentina
| | - Lisa Wiesmüller
- Department of Obstetrics and Gynecology, Ulm University, Ulm 89075, Germany
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Thakar T, Moldovan GL. The emerging determinants of replication fork stability. Nucleic Acids Res 2021; 49:7224-7238. [PMID: 33978751 PMCID: PMC8287955 DOI: 10.1093/nar/gkab344] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2021] [Revised: 04/18/2021] [Accepted: 04/20/2021] [Indexed: 12/21/2022] Open
Abstract
A universal response to replication stress is replication fork reversal, where the nascent complementary DNA strands are annealed to form a protective four-way junction allowing forks to avert DNA damage while replication stress is resolved. However, reversed forks are in turn susceptible to nucleolytic digestion of the regressed nascent DNA arms and rely on dedicated mechanisms to protect their integrity. The most well studied fork protection mechanism involves the BRCA pathway and its ability to catalyze RAD51 nucleofilament formation on the reversed arms of stalled replication forks. Importantly, the inability to prevent the degradation of reversed forks has emerged as a hallmark of BRCA deficiency and underlies genome instability and chemosensitivity in BRCA-deficient cells. In the past decade, multiple factors underlying fork stability have been discovered. These factors either cooperate with the BRCA pathway, operate independently from it to augment fork stability in its absence, or act as enablers of fork degradation. In this review, we examine these novel determinants of fork stability, explore the emergent conceptual underpinnings underlying fork protection, as well as the impact of fork protection on cellular viability and cancer therapy.
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Affiliation(s)
- Tanay Thakar
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University College of Medicine, Hershey, PA 17033, USA
| | - George-Lucian Moldovan
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University College of Medicine, Hershey, PA 17033, USA
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41
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Audoynaud C, Vagner S, Lambert S. Non-homologous end-joining at challenged replication forks: an RNA connection? Trends Genet 2021; 37:973-985. [PMID: 34238592 DOI: 10.1016/j.tig.2021.06.010] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2021] [Revised: 05/20/2021] [Accepted: 06/11/2021] [Indexed: 12/29/2022]
Abstract
Defective DNA replication, known as 'replication stress', is a source of DNA damage, a hallmark of numerous human diseases, including cancer, developmental defect, neurological disorders, and premature aging. Recent work indicates that non-homologous end-joining (NHEJ) is unexpectedly active during DNA replication to repair replication-born DNA lesions and to safeguard replication fork integrity. However, erroneous NHEJ events are deleterious to genome stability. RNAs are novel regulators of NHEJ activity through their ability to modulate the assembly of repair complexes in trans. At DNA damage sites, RNAs and DNA-embedded ribonucleotides modulate repair efficiency and fidelity. We discuss here how RNAs and associated proteins, including RNA binding proteins, may regulate NHEJ to sustain genome stability during DNA replication.
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Affiliation(s)
- Charlotte Audoynaud
- Institut Curie, Université PSL, CNRS UMR3348, INSERM U1278, 91400 Orsay, France; Université Paris-Saclay, CNRS UMR3348, INSERM U1278, 91400 Orsay, France; Equipes Labélisées Ligue Nationale Contre Le Cancer, 91400 Orsay, France
| | - Stéphan Vagner
- Institut Curie, Université PSL, CNRS UMR3348, INSERM U1278, 91400 Orsay, France; Université Paris-Saclay, CNRS UMR3348, INSERM U1278, 91400 Orsay, France; Equipes Labélisées Ligue Nationale Contre Le Cancer, 91400 Orsay, France
| | - Sarah Lambert
- Institut Curie, Université PSL, CNRS UMR3348, INSERM U1278, 91400 Orsay, France; Université Paris-Saclay, CNRS UMR3348, INSERM U1278, 91400 Orsay, France; Equipes Labélisées Ligue Nationale Contre Le Cancer, 91400 Orsay, France.
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42
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Malka MM, Eberle J, Niedermayer K, Zlotos DP, Wiesmüller L. Dual PARP and RAD51 Inhibitory Drug Conjugates Show Synergistic and Selective Effects on Breast Cancer Cells. Biomolecules 2021; 11:biom11070981. [PMID: 34356606 PMCID: PMC8301877 DOI: 10.3390/biom11070981] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2021] [Revised: 06/25/2021] [Accepted: 06/29/2021] [Indexed: 01/04/2023] Open
Abstract
The genetic principle of synthetic lethality has most successfully been exploited in therapies engaging Poly-ADP-ribose-polymerase (PARP) inhibitors to treat patients with homologous recombination (HR)-defective tumors. In this work, we went a step further following the idea of a local molecular cooperation and designed hybrid compounds M1–M3. The drug conjugates M1–M3 combine Olaparib, the first PARP inhibitor approved for clinical use, with Cpd 1, an inhibitor of RAD51 that blocks its HR functions and yet permits RAD51 nucleoprotein filament formation on single-stranded DNA. While in M2 and M3, the parental drugs are linked by -CO-(CH2)n-CO-spacers (n = 2 and 4, respectively), they are directly merged omitting the piperazine ring of Olaparib in M1. Monitoring anti-survival effects of M1–M3 in six breast cancer cell lines of different molecular subtypes showed that in each cell line, at least one of the drug conjugates decreased viability by one to two orders of magnitude compared with parental drugs. While triple-negative breast cancer (TNBC) cells with frequent BRCA1 pathway dysfunction were sensitive to spacer-linked hybrid compounds M1 and M2 regardless of their HR capacities, non-TNBC cells were responsive to the merged drug conjugate M1 only, suggesting different spatial requirements for dual inhibition in these two groups of cell lines. These results demonstrate that, depending on chemical linkage, dual PARP1-RAD51 inhibitory drugs can either sensitize non-TNBC and re-sensitize TNBC cells, or discriminate between these groups of cells.
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Affiliation(s)
- Matthews M. Malka
- Department of Pharmaceutical Chemistry, The German University in Cairo, New Cairo City, Main Entrance of Al Tagamoa Al Khames, Cairo 11835, Egypt;
| | - Julia Eberle
- Department of Obstetrics and Gynecology, Ulm University, Prittwitzstrasse 43, 89075 Ulm, Germany; (J.E.); (K.N.)
| | - Kathrin Niedermayer
- Department of Obstetrics and Gynecology, Ulm University, Prittwitzstrasse 43, 89075 Ulm, Germany; (J.E.); (K.N.)
| | - Darius P. Zlotos
- Department of Pharmaceutical Chemistry, The German University in Cairo, New Cairo City, Main Entrance of Al Tagamoa Al Khames, Cairo 11835, Egypt;
- Correspondence: (D.P.Z.); (L.W.)
| | - Lisa Wiesmüller
- Department of Obstetrics and Gynecology, Ulm University, Prittwitzstrasse 43, 89075 Ulm, Germany; (J.E.); (K.N.)
- Correspondence: (D.P.Z.); (L.W.)
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43
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Técher H, Pasero P. The Replication Stress Response on a Narrow Path Between Genomic Instability and Inflammation. Front Cell Dev Biol 2021; 9:702584. [PMID: 34249949 PMCID: PMC8270677 DOI: 10.3389/fcell.2021.702584] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2021] [Accepted: 06/03/2021] [Indexed: 02/06/2023] Open
Abstract
The genome of eukaryotic cells is particularly at risk during the S phase of the cell cycle, when megabases of chromosomal DNA are unwound to generate two identical copies of the genome. This daunting task is executed by thousands of micro-machines called replisomes, acting at fragile structures called replication forks. The correct execution of this replication program depends on the coordinated action of hundreds of different enzymes, from the licensing of replication origins to the termination of DNA replication. This review focuses on the mechanisms that ensure the completion of DNA replication under challenging conditions of endogenous or exogenous origin. It also covers new findings connecting the processing of stalled forks to the release of small DNA fragments into the cytoplasm, activating the cGAS-STING pathway. DNA damage and fork repair comes therefore at a price, which is the activation of an inflammatory response that has both positive and negative impacts on the fate of stressed cells. These new findings have broad implications for the etiology of interferonopathies and for cancer treatment.
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Affiliation(s)
- Hervé Técher
- Institut de Génétique Humaine, CNRS, Université de Montpellier, Equipe Labellisée Ligue Contre le Cancer, Montpellier, France
| | - Philippe Pasero
- Institut de Génétique Humaine, CNRS, Université de Montpellier, Equipe Labellisée Ligue Contre le Cancer, Montpellier, France
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Krishnamoorthy A, Jackson J, Mohamed T, Adolph M, Vindigni A, Cortez D. RADX prevents genome instability by confining replication fork reversal to stalled forks. Mol Cell 2021; 81:3007-3017.e5. [PMID: 34107305 DOI: 10.1016/j.molcel.2021.05.014] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2020] [Revised: 04/02/2021] [Accepted: 05/10/2021] [Indexed: 12/16/2022]
Abstract
RAD51 facilitates replication fork reversal and protects reversed forks from nuclease degradation. Although potentially a useful replication stress response mechanism, unregulated fork reversal can cause genome instability. Here we show that RADX, a single-strand DNA binding protein that binds to and destabilizes RAD51 nucleofilaments, can either inhibit or promote fork reversal depending on replication stress levels. RADX inhibits fork reversal at elongating forks, thereby preventing fork slowing and collapse. Paradoxically, in the presence of persistent replication stress, RADX localizes to stalled forks to generate reversed fork structures. Consequently, inactivating RADX prevents fork-reversal-dependent telomere dysfunction in the absence of RTEL1 and blocks nascent strand degradation when fork protection factors are inactivated. Addition of RADX increases SMARCAL1-dependent fork reversal in conditions in which pre-binding RAD51 to a model fork substrate is inhibitory. Thus, RADX directly interacts with RAD51 and single-strand DNA to confine fork reversal to persistently stalled forks.
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Affiliation(s)
- Archana Krishnamoorthy
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN 37237, USA
| | - Jessica Jackson
- Division of Oncology, Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Taha Mohamed
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN 37237, USA
| | - Madison Adolph
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN 37237, USA
| | - Alessandro Vindigni
- Division of Oncology, Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - David Cortez
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN 37237, USA.
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Ellison V, Annor GK, Freedman C, Xiao G, Lundine D, Freulich E, Prives C, Bargonetti J. Frame-shift mediated reduction of gain-of-function p53 R273H and deletion of the R273H C-terminus in breast cancer cells result in replication-stress sensitivity. Oncotarget 2021; 12:1128-1146. [PMID: 34136083 PMCID: PMC8202772 DOI: 10.18632/oncotarget.27975] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2021] [Accepted: 05/15/2021] [Indexed: 11/25/2022] Open
Abstract
We recently documented that gain-of-function (GOF) mutant p53 (mtp53) R273H in triple negative breast cancer (TNBC) cells interacts with replicating DNA and PARP1. The missense R273H GOF mtp53 has a mutated central DNA binding domain that renders it unable to bind specifically to DNA, but maintains the capacity to interact tightly with chromatin. Both the C-terminal domain (CTD) and oligomerization domain (OD) of GOF mtp53 proteins are intact and it is unclear whether these regions of mtp53 are responsible for chromatin-based DNA replication activities. We generated MDA-MB-468 cells with CRISPR-Cas9 edited versions of the CTD and OD regions of mtp53 R273H. These included a frame-shift mtp53 R273Hfs387, which depleted mtp53 protein expression; mtp53 R273HΔ381-388, which had a small deletion within the CTD; and mtp53 R273HΔ347-393, which had both the OD and CTD regions truncated. The mtp53 R273HΔ347-393 existed exclusively as monomers and disrupted the chromatin interaction of mtp53 R273H. The CRISPR variants proliferated more slowly than the parental cells and mt53 R273Hfs387 showed the most extreme phenotype. We uncovered that after thymidine-induced G1/S synchronization, but not hydroxyurea or aphidicholin, R273Hfs387 cells displayed impairment of S-phase progression while both R273HΔ347-393 and R273HΔ381-388 displayed only moderate impairment. Moreover, reduced chromatin interaction of MCM2 and PCNA in mtp53 depleted R273Hfs387 cells post thymidine-synchronization revealed delayed kinetics of replisome assembly underscoring the slow S-phase progression. Taken together our findings show that the CTD and OD domains of mtp53 R273H play critical roles in mutant p53 GOF that pertain to processes associated with DNA replication.
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Affiliation(s)
- Viola Ellison
- The Department of Biological Sciences, Hunter College, City University of New York, New York, NY, USA
| | - George K. Annor
- The Department of Biological Sciences, Hunter College, City University of New York, New York, NY, USA
- The Graduate Center Biology and Biochemistry Programs, City University of New York, New York, NY, USA
| | - Clara Freedman
- The Department of Biological Sciences, Hunter College, City University of New York, New York, NY, USA
| | - Gu Xiao
- The Department of Biological Sciences, Hunter College, City University of New York, New York, NY, USA
| | - Devon Lundine
- The Department of Biological Sciences, Hunter College, City University of New York, New York, NY, USA
- The Graduate Center Biology and Biochemistry Programs, City University of New York, New York, NY, USA
| | - Elzbieta Freulich
- Department of Biological Sciences, Columbia University, New York, NY, USA
| | - Carol Prives
- Department of Biological Sciences, Columbia University, New York, NY, USA
| | - Jill Bargonetti
- The Department of Biological Sciences, Hunter College, City University of New York, New York, NY, USA
- The Graduate Center Biology and Biochemistry Programs, City University of New York, New York, NY, USA
- Department of Cell and Developmental Biology, Weill Cornell Medical College, New York, NY, USA
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Ashour ME, Mosammaparast N. Mechanisms of damage tolerance and repair during DNA replication. Nucleic Acids Res 2021; 49:3033-3047. [PMID: 33693881 PMCID: PMC8034635 DOI: 10.1093/nar/gkab101] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2020] [Revised: 01/28/2021] [Accepted: 03/02/2021] [Indexed: 01/05/2023] Open
Abstract
Accurate duplication of chromosomal DNA is essential for the transmission of genetic information. The DNA replication fork encounters template lesions, physical barriers, transcriptional machinery, and topological barriers that challenge the faithful completion of the replication process. The flexibility of replisomes coupled with tolerance and repair mechanisms counteract these replication fork obstacles. The cell possesses several universal mechanisms that may be activated in response to various replication fork impediments, but it has also evolved ways to counter specific obstacles. In this review, we will discuss these general and specific strategies to counteract different forms of replication associated damage to maintain genomic stability.
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Affiliation(s)
- Mohamed Elsaid Ashour
- Department of Pathology & Immunology, Washington University in St. Louis School of Medicine, St. Louis, MO 63110, USA
| | - Nima Mosammaparast
- Department of Pathology & Immunology, Washington University in St. Louis School of Medicine, St. Louis, MO 63110, USA
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47
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DNA2 in Chromosome Stability and Cell Survival-Is It All about Replication Forks? Int J Mol Sci 2021; 22:ijms22083984. [PMID: 33924313 PMCID: PMC8069077 DOI: 10.3390/ijms22083984] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Revised: 04/08/2021] [Accepted: 04/10/2021] [Indexed: 01/16/2023] Open
Abstract
The conserved nuclease-helicase DNA2 has been linked to mitochondrial myopathy, Seckel syndrome, and cancer. Across species, the protein is indispensable for cell proliferation. On the molecular level, DNA2 has been implicated in DNA double-strand break (DSB) repair, checkpoint activation, Okazaki fragment processing (OFP), and telomere homeostasis. More recently, a critical contribution of DNA2 to the replication stress response and recovery of stalled DNA replication forks (RFs) has emerged. Here, we review the available functional and phenotypic data and propose that the major cellular defects associated with DNA2 dysfunction, and the links that exist with human disease, can be rationalized through the fundamental importance of DNA2-dependent RF recovery to genome duplication. Being a crucial player at stalled RFs, DNA2 is a promising target for anti-cancer therapy aimed at eliminating cancer cells by replication-stress overload.
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48
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Mirsanaye AS, Typas D, Mailand N. Ubiquitylation at Stressed Replication Forks: Mechanisms and Functions. Trends Cell Biol 2021; 31:584-597. [PMID: 33612353 DOI: 10.1016/j.tcb.2021.01.008] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2020] [Revised: 01/18/2021] [Accepted: 01/21/2021] [Indexed: 11/17/2022]
Abstract
Accurate duplication of chromosomal DNA is vital for faithful transmission of the genome during cell division. However, DNA replication integrity is frequently challenged by genotoxic insults that compromise the progression and stability of replication forks, posing a threat to genome stability. It is becoming clear that the organization of the replisome displays remarkable flexibility in responding to and overcoming a wide spectrum of fork-stalling insults, and that these transactions are dynamically orchestrated and regulated by protein post-translational modifications (PTMs) including ubiquitylation. In this review, we highlight and discuss important recent advances on how ubiquitin-mediated signaling at the replication fork plays a crucial multifaceted role in regulating replisome composition and remodeling its configuration upon replication stress, thereby ensuring high-fidelity duplication of the genome.
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Affiliation(s)
- Ann Schirin Mirsanaye
- Protein Signaling Program, Novo Nordisk Foundation Center for Protein Research, University of Copenhagen, DK-2200 Copenhagen, Denmark
| | - Dimitris Typas
- Protein Signaling Program, Novo Nordisk Foundation Center for Protein Research, University of Copenhagen, DK-2200 Copenhagen, Denmark
| | - Niels Mailand
- Protein Signaling Program, Novo Nordisk Foundation Center for Protein Research, University of Copenhagen, DK-2200 Copenhagen, Denmark; Center for Chromosome Stability, Department of Cellular and Molecular Medicine, University of Copenhagen, DK-2200 Copenhagen, Denmark.
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Liu W. Single Molecular Resolution to Monitor DNA Replication Fork Dynamics upon Stress by DNA Fiber Assay. Bio Protoc 2021; 11:e4269. [DOI: 10.21769/bioprotoc.4269] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2021] [Revised: 10/11/2021] [Accepted: 10/14/2021] [Indexed: 11/02/2022] Open
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