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Shah SB, Li Y, Li S, Hu Q, Wu T, Shi Y, Nguyen T, Ive I, Shi L, Wang H, Wu X. 53BP1 deficiency leads to hyperrecombination using break-induced replication (BIR). Nat Commun 2024; 15:8648. [PMID: 39368985 PMCID: PMC11455893 DOI: 10.1038/s41467-024-52916-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: 04/18/2024] [Accepted: 09/19/2024] [Indexed: 10/07/2024] Open
Abstract
Break-induced replication (BIR) is mutagenic, and thus its use requires tight regulation, yet the underlying mechanisms remain elusive. Here we uncover an important role of 53BP1 in suppressing BIR after end resection at double strand breaks (DSBs), distinct from its end protection activity, providing insight into the mechanisms governing BIR regulation and DSB repair pathway selection. We demonstrate that loss of 53BP1 induces BIR-like hyperrecombination, in a manner dependent on Polα-primase-mediated end fill-in DNA synthesis on single-stranded DNA (ssDNA) overhangs at DSBs, leading to PCNA ubiquitination and PIF1 recruitment to activate BIR. On broken replication forks, where BIR is required for repairing single-ended DSBs (seDSBs), SMARCAD1 displaces 53BP1 to facilitate the localization of ubiquitinated PCNA and PIF1 to DSBs for BIR activation. Hyper BIR associated with 53BP1 deficiency manifests template switching and large deletions, underscoring another aspect of 53BP1 in suppressing genome instability. The synthetic lethal interaction between the 53BP1 and BIR pathways provides opportunities for targeted cancer treatment.
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Affiliation(s)
- Sameer Bikram Shah
- Department of Molecular and Cell Biology, The Scripps Research Institute, La Jolla, CA, 92037, USA
| | - Youhang Li
- Department of Molecular and Cell Biology, The Scripps Research Institute, La Jolla, CA, 92037, USA
- College of Life Science, Capital Normal University, Beijing, 100037, China
| | - Shibo Li
- Department of Molecular and Cell Biology, The Scripps Research Institute, La Jolla, CA, 92037, USA
- College of Life Sciences, Tianjin Normal University, Tianjin, 300387, China
| | - Qing Hu
- Department of Molecular and Cell Biology, The Scripps Research Institute, La Jolla, CA, 92037, USA
| | - Tong Wu
- Department of Molecular and Cell Biology, The Scripps Research Institute, La Jolla, CA, 92037, USA
| | - Yanmeng Shi
- Department of Molecular and Cell Biology, The Scripps Research Institute, La Jolla, CA, 92037, USA
| | - Tran Nguyen
- Department of Molecular and Cell Biology, The Scripps Research Institute, La Jolla, CA, 92037, USA
| | - Isaac Ive
- Department of Molecular and Cell Biology, The Scripps Research Institute, La Jolla, CA, 92037, USA
| | - Linda Shi
- The Institute of Engineering in Medicine, University of California, San Diego, California, 92093, USA
| | - Hailong Wang
- College of Life Science, Capital Normal University, Beijing, 100037, China
| | - Xiaohua Wu
- Department of Molecular and Cell Biology, The Scripps Research Institute, La Jolla, CA, 92037, USA.
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2
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Shah SB, Li Y, Li S, Hu Q, Wu T, Shi Y, Nguyen T, Ive I, Shi L, Wang H, Wu X. 53BP1 deficiency leads to hyperrecombination using break-induced replication (BIR). BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.09.11.612483. [PMID: 39314326 PMCID: PMC11419065 DOI: 10.1101/2024.09.11.612483] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/25/2024]
Abstract
Break-induced replication (BIR) is mutagenic, and thus its use requires tight regulation, yet the underlying mechanisms remain elusive. Here we uncover an important role of 53BP1 in suppressing BIR after end resection at double strand breaks (DSBs), distinct from its end protection activity, providing insight into the mechanisms governing BIR regulation and DSB repair pathway selection. We demonstrate that loss of 53BP1 induces BIR-like hyperrecombination, in a manner dependent on Polα-primase-mediated end fill-in DNA synthesis on single-stranded DNA (ssDNA) overhangs at DSBs, leading to PCNA ubiquitination and PIF1 recruitment to activate BIR. On broken replication forks, where BIR is required for repairing single-ended DSBs (seDSBs), SMARCAD1 displaces 53BP1 to facilitate the localization of ubiquitinated PCNA and PIF1 to DSBs for BIR activation. Hyper BIR associated with 53BP1 deficiency manifests template switching and large deletions, underscoring another aspect of 53BP1 in suppressing genome instability. The synthetic lethal interaction between the 53BP1 and BIR pathways provides opportunities for targeted cancer treatment.
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Affiliation(s)
- Sameer Bikram Shah
- Department of Molecular and Cell Biology, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Youhang Li
- Department of Molecular and Cell Biology, The Scripps Research Institute, La Jolla, CA 92037, USA
- College of Life Science, Capital Normal University, Beijing 100037, China
| | - Shibo Li
- Department of Molecular and Cell Biology, The Scripps Research Institute, La Jolla, CA 92037, USA
- College of Life Sciences, Tianjin Normal University, Tianjin, 300387, China
| | - Qing Hu
- Department of Molecular and Cell Biology, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Tong Wu
- Department of Molecular and Cell Biology, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Yanmeng Shi
- Department of Molecular and Cell Biology, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Tran Nguyen
- Department of Molecular and Cell Biology, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Isaac Ive
- Department of Molecular and Cell Biology, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Linda Shi
- The Institute of Engineering in Medicine, University of California, San Diego, California 92093, USA
| | - Hailong Wang
- College of Life Science, Capital Normal University, Beijing 100037, China
| | - Xiaohua Wu
- Department of Molecular and Cell Biology, The Scripps Research Institute, La Jolla, CA 92037, USA
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3
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Paul Chowdhuri S, Das BB. TDP1 phosphorylation by CDK1 in mitosis promotes MUS81-dependent repair of trapped Top1-DNA covalent complexes. EMBO J 2024; 43:3710-3732. [PMID: 39014228 PMCID: PMC11377750 DOI: 10.1038/s44318-024-00169-3] [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: 11/15/2023] [Revised: 06/26/2024] [Accepted: 06/28/2024] [Indexed: 07/18/2024] Open
Abstract
Topoisomerase 1 (Top1) controls DNA topology, relieves DNA supercoiling during replication and transcription, and is critical for mitotic progression to the G1 phase. Tyrosyl-DNA phosphodiesterase 1 (TDP1) mediates the removal of trapped Top1-DNA covalent complexes (Top1cc). Here, we identify CDK1-dependent phosphorylation of TDP1 at residue S61 during mitosis. A TDP1 variant defective for S61 phosphorylation (TDP1-S61A) is trapped on the mitotic chromosomes, triggering DNA damage and mitotic defects. Moreover, we show that Top1cc repair in mitosis occurs via a MUS81-dependent DNA repair mechanism. Replication stress induced by camptothecin or aphidicolin leads to TDP1-S61A enrichment at common fragile sites, which over-stimulates MUS81-dependent chromatid breaks, anaphase bridges, and micronuclei, ultimately culminating in the formation of 53BP1 nuclear bodies during G1 phase. Our findings provide new insights into the cell cycle-dependent regulation of TDP1 dynamics for the repair of trapped Top1-DNA covalent complexes during mitosis that prevents genomic instability following replication stress.
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Affiliation(s)
- Srijita Paul Chowdhuri
- Laboratory of Molecular Biology, School of Biological Sciences, Indian Association for the Cultivation of Science, 2A & B, Raja S. C. Mullick Road, Jadavpur, Kolkata, West Bengal, 700032, India
| | - Benu Brata Das
- Laboratory of Molecular Biology, School of Biological Sciences, Indian Association for the Cultivation of Science, 2A & B, Raja S. C. Mullick Road, Jadavpur, Kolkata, West Bengal, 700032, India.
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4
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Kawale AS, Zou L. Regulation, functional impact, and therapeutic targeting of APOBEC3A in cancer. DNA Repair (Amst) 2024; 141:103734. [PMID: 39047499 PMCID: PMC11330346 DOI: 10.1016/j.dnarep.2024.103734] [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: 05/02/2024] [Revised: 07/16/2024] [Accepted: 07/19/2024] [Indexed: 07/27/2024]
Abstract
Enzymes of the apolipoprotein B mRNA editing catalytic polypeptide like (APOBEC) family are cytosine deaminases that convert cytosine to uracil in DNA and RNA. Among these proteins, APOBEC3 sub-family members, APOBEC3A (A3A) and APOBEC3B (A3B), are prominent sources of mutagenesis in cancer cells. The aberrant expression of A3A and A3B in cancer cells leads to accumulation of mutations with specific single-base substitution (SBS) signatures, characterized by C→T and C→G changes, in a number of tumor types. In addition to fueling mutagenesis, A3A and A3B, particularly A3A, induce DNA replication stress, DNA damage, and chromosomal instability through their catalytic activities, triggering a range of cellular responses. Thus, A3A/B have emerged as key drivers of genome evolution during cancer development, contributing to tumorigenesis, tumor heterogeneity, and therapeutic resistance. Yet, the expression of A3A/B in cancer cells presents a cancer vulnerability that can be exploited therapeutically. In this review, we discuss the recent studies that shed light on the mechanisms regulating A3A expression and the impact of A3A in cancer. We also review recent advances in the development of A3A inhibitors and provide perspectives on the future directions of A3A research.
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Affiliation(s)
- Ajinkya S Kawale
- Massachusetts General Hospital Cancer Center and Harvard Medical School, Boston, MA, USA
| | - Lee Zou
- Department of Pharmacology and Cancer Biology, Duke University, Durham, NC, USA.
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5
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Benamar M, Eki R, Du KP, Abbas T. Break-induced replication drives large-scale genomic amplifications in cancer cells. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.08.27.609980. [PMID: 39253455 PMCID: PMC11383296 DOI: 10.1101/2024.08.27.609980] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/11/2024]
Abstract
DNA double-strand breaks (DSBs) are highly toxic lesions that underly the efficacy of ionizing radiation (IR) and a large number of cytotoxic chemotherapies 1-3 . Yet, abnormal repair of DSBs is associated with genomic instability and may contribute to cancer heterogeneity and tumour evolution. Here, we show that DSBs induced by IR, by DSB-inducing chemotherapeutics, or by the expression of a rare-cutting restriction endonuclease induce large-scale genomic amplification in human cancer cells. Importantly, the extent of DSB-induced genomic amplification (DIGA) in a panel of melanoma cell lines correlated with the degree of cytotoxicity elicited by IR, suggesting that DIGA contributes significantly to DSB-induced cancer cell lethality. DIGA, which is mediated through conservative DNA synthesis, does not require origin re-licensing, and is enhanced by the depletion or deletion of the methyltransferases SET8 and SUV4-20H1, which function sequentially to mono- and di-methylate histone H4 lysine 20 (H4K20) at DSBs to facilitate the recruitment of 53BP1-RIF1 and its downstream effector shieldin complex to DSBs to prevent hyper-resection 4-11 . Consistently, DIGA was enhanced in cells lacking 53BP1 or RIF1, or in cells that lacked components of the shieldin complex or of other factors that help recruit 53BP1 to DSBs. Mechanistically, DIGA requires MRE11/CtIP and EXO1, factors that promote resection and hyper-resection at DSBs, and is dependent on the catalytic activity of the RAD51 recombinase. Furthermore, deletion or depletion of POLD3, POLD4, or RAD52, proteins involved in break-induced replication (BIR), significantly inhibited DIGA, suggesting that DIGA is mediated through a RAD51-dependent BIR-like process. DIGA induction was maximal if the cells encountered DSBs in early and mid S-phase, whereas cells competent for homologous recombination (in late S and G2) exhibited less DIGA induction. We propose that unshielded, hyper-resected ends of DSBs may nucleate a replication-like intermediate that enables cytotoxic long-range genomic DNA amplification mediated through BIR.
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Bedir M, Outwin E, Colnaghi R, Bassett L, Abramowicz I, O'Driscoll M. A novel role for the peptidyl-prolyl cis-trans isomerase Cyclophilin A in DNA-repair following replication fork stalling via the MRE11-RAD50-NBS1 complex. EMBO Rep 2024; 25:3432-3455. [PMID: 38943005 PMCID: PMC11315929 DOI: 10.1038/s44319-024-00184-9] [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: 02/02/2024] [Revised: 05/28/2024] [Accepted: 06/05/2024] [Indexed: 06/30/2024] Open
Abstract
Cyclosporin A (CsA) induces DNA double-strand breaks in LIG4 syndrome fibroblasts, specifically upon transit through S-phase. The basis underlying this has not been described. CsA-induced genomic instability may reflect a direct role of Cyclophilin A (CYPA) in DNA repair. CYPA is a peptidyl-prolyl cis-trans isomerase (PPI). CsA inhibits the PPI activity of CYPA. Using an integrated approach involving CRISPR/Cas9-engineering, siRNA, BioID, co-immunoprecipitation, pathway-specific DNA repair investigations as well as protein expression interaction analysis, we describe novel impacts of CYPA loss and inhibition on DNA repair. We characterise a direct CYPA interaction with the NBS1 component of the MRE11-RAD50-NBS1 complex, providing evidence that CYPA influences DNA repair at the level of DNA end resection. We define a set of genetic vulnerabilities associated with CYPA loss and inhibition, identifying DNA replication fork protection as an important determinant of viability. We explore examples of how CYPA inhibition may be exploited to selectively kill cancers sharing characteristic genomic instability profiles, including MYCN-driven Neuroblastoma, Multiple Myeloma and Chronic Myelogenous Leukaemia. These findings propose a repurposing strategy for Cyclophilin inhibitors.
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Affiliation(s)
- Marisa Bedir
- Human DNA Damage Response Disorders Group, Genome Damage & Stability Centre, University of Sussex, Brighton, BN1 9RQ, UK
| | - Emily Outwin
- Human DNA Damage Response Disorders Group, Genome Damage & Stability Centre, University of Sussex, Brighton, BN1 9RQ, UK
| | - Rita Colnaghi
- Human DNA Damage Response Disorders Group, Genome Damage & Stability Centre, University of Sussex, Brighton, BN1 9RQ, UK
| | - Lydia Bassett
- Human DNA Damage Response Disorders Group, Genome Damage & Stability Centre, University of Sussex, Brighton, BN1 9RQ, UK
| | - Iga Abramowicz
- Human DNA Damage Response Disorders Group, Genome Damage & Stability Centre, University of Sussex, Brighton, BN1 9RQ, UK
| | - Mark O'Driscoll
- Human DNA Damage Response Disorders Group, Genome Damage & Stability Centre, University of Sussex, Brighton, BN1 9RQ, UK.
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7
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Carreira R, Lama-Diaz T, Crugeiras M, Aguado F, Sebesta M, Krejci L, Blanco M. Concurrent D-loop cleavage by Mus81 and Yen1 yields half-crossover precursors. Nucleic Acids Res 2024; 52:7012-7030. [PMID: 38832625 PMCID: PMC11229367 DOI: 10.1093/nar/gkae453] [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: 09/22/2023] [Revised: 05/05/2024] [Accepted: 05/14/2024] [Indexed: 06/05/2024] Open
Abstract
Homologous recombination involves the formation of branched DNA molecules that may interfere with chromosome segregation. To resolve these persistent joint molecules, cells rely on the activation of structure-selective endonucleases (SSEs) during the late stages of the cell cycle. However, the premature activation of SSEs compromises genome integrity, due to untimely processing of replication and/or recombination intermediates. Here, we used a biochemical approach to show that the budding yeast SSEs Mus81 and Yen1 possess the ability to cleave the central recombination intermediate known as the displacement loop or D-loop. Moreover, we demonstrate that, consistently with previous genetic data, the simultaneous action of Mus81 and Yen1, followed by ligation, is sufficient to recreate the formation of a half-crossover precursor in vitro. Our results provide not only mechanistic explanation for the formation of a half-crossover, but also highlight the critical importance for precise regulation of these SSEs to prevent chromosomal rearrangements.
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Affiliation(s)
- Raquel Carreira
- Department of Biochemistry and Molecular Biology, CIMUS, Universidade de Santiago de Compostela-Instituto de Investigación Sanitaria (IDIS), Santiago de Compostela, A Coruña 15782, Spain
| | - Tomas Lama-Diaz
- Department of Biochemistry and Molecular Biology, CIMUS, Universidade de Santiago de Compostela-Instituto de Investigación Sanitaria (IDIS), Santiago de Compostela, A Coruña 15782, Spain
| | - Maria Crugeiras
- Department of Biochemistry and Molecular Biology, CIMUS, Universidade de Santiago de Compostela-Instituto de Investigación Sanitaria (IDIS), Santiago de Compostela, A Coruña 15782, Spain
| | - F Javier Aguado
- Department of Biochemistry and Molecular Biology, CIMUS, Universidade de Santiago de Compostela-Instituto de Investigación Sanitaria (IDIS), Santiago de Compostela, A Coruña 15782, Spain
| | - Marek Sebesta
- Department of Biology and National Centre for Biomolecular Research, Masaryk University, Brno 62500, Czech Republic
| | - Lumir Krejci
- Department of Biology and National Centre for Biomolecular Research, Masaryk University, Brno 62500, Czech Republic
| | - Miguel G Blanco
- Department of Biochemistry and Molecular Biology, CIMUS, Universidade de Santiago de Compostela-Instituto de Investigación Sanitaria (IDIS), Santiago de Compostela, A Coruña 15782, Spain
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8
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Hernández Sánchez-Rebato M, Schubert V, White CI. Meiotic double-strand break repair DNA synthesis tracts in Arabidopsis thaliana. PLoS Genet 2024; 20:e1011197. [PMID: 39012914 PMCID: PMC11280534 DOI: 10.1371/journal.pgen.1011197] [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: 02/25/2024] [Revised: 07/26/2024] [Accepted: 06/27/2024] [Indexed: 07/18/2024] Open
Abstract
We report here the successful labelling of meiotic prophase I DNA synthesis in the flowering plant, Arabidopsis thaliana. Incorporation of the thymidine analogue, EdU, enables visualisation of the footprints of recombinational repair of programmed meiotic DNA double-strand breaks (DSB), with ~400 discrete, SPO11-dependent, EdU-labelled chromosomal foci clearly visible at pachytene and later stages of meiosis. This number equates well with previous estimations of 200-300 DNA double-strand breaks per meiosis in Arabidopsis, confirming the power of this approach to detect the repair of most or all SPO11-dependent meiotic DSB repair events. The chromosomal distribution of these DNA-synthesis foci accords with that of early recombination markers and MLH1, which marks Class I crossover sites. Approximately 10 inter-homologue cross-overs (CO) have been shown to occur in each Arabidopsis male meiosis and, athough very probably under-estimated, an equivalent number of inter-homologue gene conversions (GC) have been described. Thus, at least 90% of meiotic recombination events, and very probably more, have not previously been accessible for analysis. Visual examination of the patterns of the foci on the synapsed pachytene chromosomes corresponds well with expectations from the different mechanisms of meiotic recombination and notably, no evidence for long Break-Induced Replication DNA synthesis tracts was found. Labelling of meiotic prophase I, SPO11-dependent DNA synthesis holds great promise for further understanding of the molecular mechanisms of meiotic recombination, at the heart of reproduction and evolution of eukaryotes.
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Affiliation(s)
- Miguel Hernández Sánchez-Rebato
- Institut de Génétique, Reproduction et Développement, CNRS UMR 6293, INSERM U1103, Université Clermont Auvergne, Clermont-Ferrand, France
| | - Veit Schubert
- Leibniz Institute of Plant Genetics and Crop Plant Research (IPK) Gatersleben, Seeland, Germany
| | - Charles I. White
- Institut de Génétique, Reproduction et Développement, CNRS UMR 6293, INSERM U1103, Université Clermont Auvergne, Clermont-Ferrand, France
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9
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Gadgil RY, Rider SD, Shrestha R, Alhawach V, Hitch D, Leffak M. Microsatellite break-induced replication generates highly mutagenized extrachromosomal circular DNAs. NAR Cancer 2024; 6:zcae027. [PMID: 38854437 PMCID: PMC11161834 DOI: 10.1093/narcan/zcae027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2024] [Revised: 05/17/2024] [Accepted: 05/24/2024] [Indexed: 06/11/2024] Open
Abstract
Extrachromosomal circular DNAs (eccDNAs) are produced from all regions of the eucaryotic genome. We used inverse PCR of non-B microsatellites capable of forming hairpin, triplex, quadruplex and AT-rich structures integrated at a common ectopic chromosomal site to show that these non-B DNAs generate highly mutagenized eccDNAs by replication-dependent mechanisms. Mutagenesis occurs within the non-B DNAs and extends several kilobases bidirectionally into flanking and nonallelic DNA. Each non-B DNA exhibits a different pattern of mutagenesis, while sister clones containing the same non-B DNA also display distinct patterns of recombination, microhomology-mediated template switching and base substitutions. Mutations include mismatches, short duplications, long nontemplated insertions, large deletions and template switches to sister chromatids and nonallelic chromosomes. Drug-induced replication stress or the depletion of DNA repair factors Rad51, the COPS2 signalosome subunit or POLη change the pattern of template switching and alter the eccDNA mutagenic profiles. We propose an asynchronous capture model based on break-induced replication from microsatellite-induced DNA double strand breaks to account for the generation and circularization of mutagenized eccDNAs and the appearance of genomic homologous recombination deficiency (HRD) scars. These results may help to explain the appearance of tumor eccDNAS and their roles in neoantigen production, oncogenesis and resistance to chemotherapy.
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Affiliation(s)
- Rujuta Yashodhan Gadgil
- Department of Biochemistry and Molecular Biology, Boonshoft School of Medicine, Wright State University, Dayton, OH 45435, USA
| | - S Dean Rider
- Department of Biochemistry and Molecular Biology, Boonshoft School of Medicine, Wright State University, Dayton, OH 45435, USA
| | - Resha Shrestha
- Department of Biochemistry and Molecular Biology, Boonshoft School of Medicine, Wright State University, Dayton, OH 45435, USA
| | - Venicia Alhawach
- Department of Biochemistry and Molecular Biology, Boonshoft School of Medicine, Wright State University, Dayton, OH 45435, USA
| | - David C Hitch
- Department of Biochemistry and Molecular Biology, Boonshoft School of Medicine, Wright State University, Dayton, OH 45435, USA
| | - Michael Leffak
- Department of Biochemistry and Molecular Biology, Boonshoft School of Medicine, Wright State University, Dayton, OH 45435, USA
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10
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Theofilatos D, Ho T, Waitt G, Äijö T, Schiapparelli LM, Soderblom EJ, Tsagaratou A. Deciphering the TET3 interactome in primary thymic developing T cells. iScience 2024; 27:109782. [PMID: 38711449 PMCID: PMC11070343 DOI: 10.1016/j.isci.2024.109782] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2023] [Revised: 03/04/2024] [Accepted: 04/15/2024] [Indexed: 05/08/2024] Open
Abstract
Ten-eleven translocation (TET) proteins are DNA dioxygenases that mediate active DNA demethylation. TET3 is the most highly expressed TET protein in thymic developing T cells. TET3, either independently or in cooperation with TET1 or TET2, has been implicated in T cell lineage specification by regulating DNA demethylation. However, TET-deficient mice exhibit complex phenotypes, suggesting that TET3 exerts multifaceted roles, potentially by interacting with other proteins. We performed liquid chromatography with tandem mass spectrometry in primary developing T cells to identify TET3 interacting partners in endogenous, in vivo conditions. We discover TET3 interacting partners. Our data establish that TET3 participates in a plethora of fundamental biological processes, such as transcriptional regulation, RNA polymerase elongation, splicing, DNA repair, and DNA replication. This resource brings in the spotlight emerging functions of TET3 and sets the stage for systematic studies to dissect the precise mechanistic contributions of TET3 in shaping T cell biology.
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Affiliation(s)
- Dimitris Theofilatos
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Tricia Ho
- Duke Proteomics and Metabolomics Core Facility, Duke Center for Genomic and Computational Biology, Duke University, Durham, NC, USA
| | - Greg Waitt
- Duke Proteomics and Metabolomics Core Facility, Duke Center for Genomic and Computational Biology, Duke University, Durham, NC, USA
| | - Tarmo Äijö
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | | | - Erik J. Soderblom
- Duke Proteomics and Metabolomics Core Facility, Duke Center for Genomic and Computational Biology, Duke University, Durham, NC, USA
- Department of Cell Biology, Duke University, Durham, NC, USA
| | - Ageliki Tsagaratou
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
- Department of Genetics, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
- Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
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11
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Carrothers E, Appleby M, Lai V, Kozbenko T, Alomar D, Smith BJ, Hamada N, Hinton P, Ainsbury EA, Hocking R, Yauk C, Wilkins RC, Chauhan V. AOP report: Development of an adverse outcome pathway for deposition of energy leading to cataracts. ENVIRONMENTAL AND MOLECULAR MUTAGENESIS 2024. [PMID: 38644659 DOI: 10.1002/em.22594] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2024] [Accepted: 03/21/2024] [Indexed: 04/23/2024]
Abstract
Cataracts are one of the leading causes of blindness, with an estimated 95 million people affected worldwide. A hallmark of cataract development is lens opacification, typically associated not only with aging but also radiation exposure as encountered by interventional radiologists and astronauts during the long-term space mission. To better understand radiation-induced cataracts, the adverse outcome pathway (AOP) framework was used to structure and evaluate knowledge across biological levels of organization (e.g., macromolecular, cell, tissue, organ, organism and population). AOPs identify a sequence of key events (KEs) causally connected by key event relationships (KERs) beginning with a molecular initiating event to an adverse outcome (AO) of relevance to regulatory decision-making. To construct the cataract AO and retrieve evidence to support it, a scoping review methodology was used to filter, screen, and review studies based on the modified Bradford Hill criteria. Eight KEs were identified that were moderately supported by empirical evidence (e.g., dose-, time-, incidence-concordance) across the adjacent (directly linked) relationships using well-established endpoints. Over half of the evidence to justify the KER linkages was derived from the evidence stream of biological plausibility. Early KEs of oxidative stress and protein modifications had strong linkages to downstream KEs and could be the focus of countermeasure development. Several identified knowledge gaps and inconsistencies related to the quantitative understanding of KERs which could be the basis of future research, most notably directed to experiments in the range of low or moderate doses and dose-rates, relevant to radiation workers and other occupational exposures.
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Affiliation(s)
- Emma Carrothers
- Consumer and Clinical Radiation Protection Bureau, Environmental and Radiation Health Sciences Directorate, Health Canada, Ottawa, Ontario, Canada
| | - Meghan Appleby
- Consumer and Clinical Radiation Protection Bureau, Environmental and Radiation Health Sciences Directorate, Health Canada, Ottawa, Ontario, Canada
| | - Vita Lai
- Consumer and Clinical Radiation Protection Bureau, Environmental and Radiation Health Sciences Directorate, Health Canada, Ottawa, Ontario, Canada
| | - Tatiana Kozbenko
- Consumer and Clinical Radiation Protection Bureau, Environmental and Radiation Health Sciences Directorate, Health Canada, Ottawa, Ontario, Canada
| | - Dalya Alomar
- Consumer and Clinical Radiation Protection Bureau, Environmental and Radiation Health Sciences Directorate, Health Canada, Ottawa, Ontario, Canada
| | - Benjamin J Smith
- Consumer and Clinical Radiation Protection Bureau, Environmental and Radiation Health Sciences Directorate, Health Canada, Ottawa, Ontario, Canada
| | - Nobuyuki Hamada
- Biology and Environmental Chemistry Division, Sustainable System Research Laboratory, Central Research Institute of Electric Power Industry (CRIEPI), Chiba, Japan
| | - Patricia Hinton
- Defense Research & Development Canada, Canadian Forces Environmental Medicine Establishment, Toronto, Ontario, Canada
| | - Elizabeth A Ainsbury
- Radiation, Chemical and Environmental Hazards Division, UK Health Security Agency, Birmingham, UK
- Environmental Research Group within the School of Public Health, Faculty of Medicine at Imperial College of Science, Technology and Medicine, London, UK
| | - Robyn Hocking
- Learning and Knowledge and Library Services, Health Canada, Ottawa, Ontario, Canada
| | - Carole Yauk
- Department of Biology, University of Ottawa, Ottawa, Ontario, Canada
| | - Ruth C Wilkins
- Consumer and Clinical Radiation Protection Bureau, Environmental and Radiation Health Sciences Directorate, Health Canada, Ottawa, Ontario, Canada
| | - Vinita Chauhan
- Consumer and Clinical Radiation Protection Bureau, Environmental and Radiation Health Sciences Directorate, Health Canada, Ottawa, Ontario, Canada
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12
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Fragkoulis G, Hangas A, Fekete Z, Michell C, Moraes C, Willcox S, Griffith JD, Goffart S, Pohjoismäki JO. Linear DNA-driven recombination in mammalian mitochondria. Nucleic Acids Res 2024; 52:3088-3105. [PMID: 38300793 PMCID: PMC11014290 DOI: 10.1093/nar/gkae040] [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: 02/01/2023] [Accepted: 01/11/2024] [Indexed: 02/03/2024] Open
Abstract
Mitochondrial DNA (mtDNA) recombination in animals has remained enigmatic due to its uniparental inheritance and subsequent homoplasmic state, which excludes the biological need for genetic recombination, as well as limits tools to study it. However, molecular recombination is an important genome maintenance mechanism for all organisms, most notably being required for double-strand break repair. To demonstrate the existence of mtDNA recombination, we took advantage of a cell model with two different types of mitochondrial genomes and impaired its ability to degrade broken mtDNA. The resulting excess of linear DNA fragments caused increased formation of cruciform mtDNA, appearance of heterodimeric mtDNA complexes and recombinant mtDNA genomes, detectable by Southern blot and by long range PacBio® HiFi sequencing approach. Besides utilizing different electrophoretic methods, we also directly observed molecular complexes between different mtDNA haplotypes and recombination intermediates using transmission electron microscopy. We propose that the known copy-choice recombination by mitochondrial replisome could be sufficient for the needs of the small genome, thus removing the requirement for a specialized mitochondrial recombinase. The error-proneness of this system is likely to contribute to the formation of pathological mtDNA rearrangements.
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Affiliation(s)
- Georgios Fragkoulis
- Department of Environmental and Biological Sciences, University of Eastern Finland, PO Box 111, 80101 Joensuu, Finland
| | - Anu Hangas
- Department of Environmental and Biological Sciences, University of Eastern Finland, PO Box 111, 80101 Joensuu, Finland
| | - Zsófia Fekete
- Department of Environmental and Biological Sciences, University of Eastern Finland, PO Box 111, 80101 Joensuu, Finland
- Department of Genetics and Genomics, Institute of Genetics and Biotechnology, Hungarian University of Agriculture and Life Sciences, Gödöllő, Hungary
- Doctoral School of Animal Biotechnology and Animal Science, Hungarian University of Agriculture and Life Sciences, Gödöllő, Hungary
| | - Craig Michell
- Red Sea Research Center, Division of Biological and Environmental Science and Engineering, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
| | - Carlos T Moraes
- Department of Neurology, University of Miami Miller School of Medicine, Miami,FL, USA
| | - Smaranda Willcox
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, USA
| | - Jack D Griffith
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, USA
| | - Steffi Goffart
- Department of Environmental and Biological Sciences, University of Eastern Finland, PO Box 111, 80101 Joensuu, Finland
| | - Jaakko L O Pohjoismäki
- Department of Environmental and Biological Sciences, University of Eastern Finland, PO Box 111, 80101 Joensuu, Finland
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13
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Muoio D, Laspata N, Dannenberg RL, Curry C, Darkoa-Larbi S, Hedglin M, Uttam S, Fouquerel E. PARP2 promotes Break Induced Replication-mediated telomere fragility in response to replication stress. Nat Commun 2024; 15:2857. [PMID: 38565848 PMCID: PMC10987537 DOI: 10.1038/s41467-024-47222-7] [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: 05/30/2023] [Accepted: 03/22/2024] [Indexed: 04/04/2024] Open
Abstract
PARP2 is a DNA-dependent ADP-ribosyl transferase (ARTs) enzyme with Poly(ADP-ribosyl)ation activity that is triggered by DNA breaks. It plays a role in the Base Excision Repair pathway, where it has overlapping functions with PARP1. However, additional roles for PARP2 have emerged in the response of cells to replication stress. In this study, we demonstrate that PARP2 promotes replication stress-induced telomere fragility and prevents telomere loss following chronic induction of oxidative DNA lesions and BLM helicase depletion. Telomere fragility results from the activity of the break-induced replication pathway (BIR). During this process, PARP2 promotes DNA end resection, strand invasion and BIR-dependent mitotic DNA synthesis by orchestrating POLD3 recruitment and activity. Our study has identified a role for PARP2 in the response to replication stress. This finding may lead to the development of therapeutic approaches that target DNA-dependent ART enzymes, particularly in cancer cells with high levels of replication stress.
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Affiliation(s)
- Daniela Muoio
- UPMC Hillman Cancer Center, University of Pittsburgh Cancer Institute, Department of Pharmacology and Chemical Biology, Pittsburgh, PA, 15213, USA
| | - Natalie Laspata
- UPMC Hillman Cancer Center, University of Pittsburgh Cancer Institute, Department of Pharmacology and Chemical Biology, Pittsburgh, PA, 15213, USA
- Department of Biochemistry and Molecular Biology, Thomas Jefferson University, 233S. 10th street, Philadelphia, PA, 19107, USA
| | - Rachel L Dannenberg
- Department of Chemistry, The Pennsylvania State University, University park, State College, PA, 16802, USA
| | - Caroline Curry
- Department of Biochemistry and Molecular Biology, Thomas Jefferson University, 233S. 10th street, Philadelphia, PA, 19107, USA
| | - Simone Darkoa-Larbi
- Department of Biochemistry and Molecular Biology, Thomas Jefferson University, 233S. 10th street, Philadelphia, PA, 19107, USA
| | - Mark Hedglin
- Department of Chemistry, The Pennsylvania State University, University park, State College, PA, 16802, USA
| | - Shikhar Uttam
- Department of Computational and Systems Biology, UPMC Hillman Cancer Center, University of Pittsburgh, 5117 Centre Avenue, Pittsburgh, PA, 15213, USA
| | - Elise Fouquerel
- UPMC Hillman Cancer Center, University of Pittsburgh Cancer Institute, Department of Pharmacology and Chemical Biology, Pittsburgh, PA, 15213, USA.
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14
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Piguet B, Houseley J. Transcription as source of genetic heterogeneity in budding yeast. Yeast 2024; 41:171-185. [PMID: 38196235 DOI: 10.1002/yea.3926] [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: 10/07/2023] [Revised: 12/10/2023] [Accepted: 12/20/2023] [Indexed: 01/11/2024] Open
Abstract
Transcription presents challenges to genome stability both directly, by altering genome topology and exposing single-stranded DNA to chemical insults and nucleases, and indirectly by introducing obstacles to the DNA replication machinery. Such obstacles include the RNA polymerase holoenzyme itself, DNA-bound regulatory factors, G-quadruplexes and RNA-DNA hybrid structures known as R-loops. Here, we review the detrimental impacts of transcription on genome stability in budding yeast, as well as the mitigating effects of transcription-coupled nucleotide excision repair and of systems that maintain DNA replication fork processivity and integrity. Interactions between DNA replication and transcription have particular potential to induce mutation and structural variation, but we conclude that such interactions must have only minor effects on DNA replication by the replisome with little if any direct mutagenic outcome. However, transcription can significantly impair the fidelity of replication fork rescue mechanisms, particularly Break Induced Replication, which is used to restart collapsed replication forks when other means fail. This leads to de novo mutations, structural variation and extrachromosomal circular DNA formation that contribute to genetic heterogeneity, but only under particular conditions and in particular genetic contexts, ensuring that the bulk of the genome remains extremely stable despite the seemingly frequent interactions between transcription and DNA replication.
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15
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Du D, Yang Y, Zhang Y, Wang G, Chen L, Guan X, Rasmussen LJ, Liu D. MRE11A: a novel negative regulator of human DNA mismatch repair. Cell Mol Biol Lett 2024; 29:37. [PMID: 38486171 PMCID: PMC10938699 DOI: 10.1186/s11658-024-00547-z] [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: 12/07/2023] [Accepted: 02/08/2024] [Indexed: 03/17/2024] Open
Abstract
BACKGROUND DNA mismatch repair (MMR) is a highly conserved pathway that corrects DNA replication errors, the loss of which is attributed to the development of various types of cancers. Although well characterized, MMR factors remain to be identified. As a 3'-5' exonuclease and endonuclease, meiotic recombination 11 homolog A (MRE11A) is implicated in multiple DNA repair pathways. However, the role of MRE11A in MMR is unclear. METHODS Initially, short-term and long-term survival assays were used to measure the cells' sensitivity to N-methyl-N'-nitro-N-nitrosoguanidine (MNNG). Meanwhile, the level of apoptosis was also determined by flow cytometry after MNNG treatment. Western blotting and immunofluorescence assays were used to evaluate the DNA damage within one cell cycle after MNNG treatment. Next, a GFP-heteroduplex repair assay and microsatellite stability test were used to measure the MMR activities in cells. To investigate the mechanisms, western blotting, the GFP-heteroduplex repair assay, and chromatin immunoprecipitation were used. RESULTS We show that knockdown of MRE11A increased the sensitivity of HeLa cells to MNNG treatment, as well as the MNNG-induced DNA damage and apoptosis, implying a potential role of MRE11 in MMR. Moreover, we found that MRE11A was largely recruited to chromatin and negatively regulated the DNA damage signals within the first cell cycle after MNNG treatment. We also showed that knockdown of MRE11A increased, while overexpressing MRE11A decreased, MMR activity in HeLa cells, suggesting that MRE11A negatively regulates MMR activity. Furthermore, we show that recruitment of MRE11A to chromatin requires MLH1 and that MRE11A competes with PMS2 for binding to MLH1. This decreases PMS2 levels in whole cells and on chromatin, and consequently comprises MMR activity. CONCLUSIONS Our findings reveal that MRE11A is a negative regulator of human MMR.
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Affiliation(s)
- Demin Du
- Department of Human Anatomy and Histoembryology, Nanjing University of Chinese Medicine, Nanjing, 210023, China
| | - Yueyan Yang
- Affiliated Hospital of Nanjing University of Chinese Medicine, Nanjing, 210023, China
| | - Yuanyuan Zhang
- Department of Human Anatomy and Histoembryology, Nanjing University of Chinese Medicine, Nanjing, 210023, China
| | - Guanxiong Wang
- Department of Human Anatomy and Histoembryology, Nanjing University of Chinese Medicine, Nanjing, 210023, China
| | - Liying Chen
- Department of Human Anatomy and Histoembryology, Nanjing University of Chinese Medicine, Nanjing, 210023, China
| | - Xiaowei Guan
- Department of Human Anatomy and Histoembryology, Nanjing University of Chinese Medicine, Nanjing, 210023, China.
| | - Lene Juel Rasmussen
- Center for Healthy Aging, Department of Cellular and Molecular Medicine, University of Copenhagen, 2200, Copenhagen, Denmark.
| | - Dekang Liu
- Department of Human Anatomy and Histoembryology, Nanjing University of Chinese Medicine, Nanjing, 210023, China.
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16
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Ma JY, Xia TJ, Li S, Yin S, Luo SM, Li G. Germline cell de novo mutations and potential effects of inflammation on germline cell genome stability. Semin Cell Dev Biol 2024; 154:316-327. [PMID: 36376195 DOI: 10.1016/j.semcdb.2022.11.003] [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: 07/14/2022] [Revised: 11/05/2022] [Accepted: 11/06/2022] [Indexed: 11/13/2022]
Abstract
Uncontrolled pathogenic genome mutations in germline cells might impair adult fertility, lead to birth defects or even affect the adaptability of a species. Understanding the sources of DNA damage, as well as the features of damage response in germline cells are the overarching tasks to reduce the mutations in germline cells. With the accumulation of human genome data and genetic reports, genome variants formed in germline cells are being extensively explored. However, the sources of DNA damage, the damage repair mechanisms, and the effects of DNA damage or mutations on the development of germline cells are still unclear. Besides exogenous triggers of DNA damage such as irradiation and genotoxic chemicals, endogenous exposure to inflammation may also contribute to the genome instability of germline cells. In this review, we summarized the features of de novo mutations and the specific DNA damage responses in germline cells and explored the possible roles of inflammation on the genome stability of germline cells.
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Affiliation(s)
- Jun-Yu Ma
- Fertility Preservation Lab, Guangdong-Hong Kong Metabolism & Reproduction Joint Laboratory, Reproductive Medicine Center, Guangdong Second Provincial General Hospital, Guangzhou, China.
| | - Tian-Jin Xia
- Fertility Preservation Lab, Guangdong-Hong Kong Metabolism & Reproduction Joint Laboratory, Reproductive Medicine Center, Guangdong Second Provincial General Hospital, Guangzhou, China; College of Life Sciences, Qingdao Agricultural University, Qingdao, China
| | - Shuai Li
- Center for Clinical Epidemiology and Methodology, Guangdong Second Provincial General Hospital, Guangzhou, China
| | - Shen Yin
- College of Life Sciences, Qingdao Agricultural University, Qingdao, China.
| | - Shi-Ming Luo
- Fertility Preservation Lab, Guangdong-Hong Kong Metabolism & Reproduction Joint Laboratory, Reproductive Medicine Center, Guangdong Second Provincial General Hospital, Guangzhou, China.
| | - Guowei Li
- Center for Clinical Epidemiology and Methodology, Guangdong Second Provincial General Hospital, Guangzhou, China.
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17
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Collin V, Biquand É, Tremblay V, Lavoie ÉG, Blondeau A, Gravel A, Galloy M, Lashgari A, Dessapt J, Côté J, Flamand L, Fradet-Turcotte A. The immediate-early protein 1 of human herpesvirus 6B interacts with NBS1 and inhibits ATM signaling. EMBO Rep 2024; 25:725-744. [PMID: 38177923 PMCID: PMC10897193 DOI: 10.1038/s44319-023-00035-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: 03/07/2023] [Revised: 12/03/2023] [Accepted: 12/06/2023] [Indexed: 01/06/2024] Open
Abstract
Viral infection often trigger an ATM serine/threonine kinase (ATM)-dependent DNA damage response in host cells that suppresses viral replication. Viruses evolved different strategies to counteract this antiviral surveillance system. Here, we report that human herpesvirus 6B (HHV-6B) infection causes genomic instability by suppressing ATM signaling in host cells. Expression of immediate-early protein 1 (IE1) phenocopies this phenotype and blocks homology-directed double-strand break repair. Mechanistically, IE1 interacts with NBS1, and inhibits ATM signaling through two distinct domains. HHV-6B seems to efficiently inhibit ATM signaling as further depletion of either NBS1 or ATM do not significantly boost viral replication in infected cells. Interestingly, viral integration of HHV-6B into the host's telomeres is not strictly dependent on NBS1, challenging current models where integration occurs through homology-directed repair. Given that spontaneous IE1 expression has been detected in cells of subjects with inherited chromosomally-integrated form of HHV-6B (iciHHV-6B), a condition associated with several health conditions, our results raise the possibility of a link between genomic instability and the development of iciHHV-6-associated diseases.
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Affiliation(s)
- Vanessa Collin
- Division of Infectious Disease and Immunity, Centre Hospitalier Universitaire (CHU) de Québec-Université Laval Research Center, Quebec City, QC, G1V 4G2, Canada
- Department of Microbiology, Infectious Disease and Immunology, Faculty of Medicine, Université Laval, Quebec City, QC, G1V 0A6, Canada
| | - Élise Biquand
- Oncology Division, Centre Hospitalier Universitaire (CHU) de Québec-Université Laval Research Center, Quebec City, QC, G1R 2J6, Canada
- Department of Molecular biology, Medical Biochemistry and Pathology, Faculty of Medicine, Université Laval, Québec City, QC, G1V 0A6, Canada
- Université Laval Cancer Research Center, Université Laval, Quebec City, QC, G1R 3S3, Canada
- INSERM, Centre d'Étude des Pathologies Respiratoires (CEPR), UMR 1100, Université de Tours, Tours, France
| | - Vincent Tremblay
- Oncology Division, Centre Hospitalier Universitaire (CHU) de Québec-Université Laval Research Center, Quebec City, QC, G1R 2J6, Canada
- Department of Molecular biology, Medical Biochemistry and Pathology, Faculty of Medicine, Université Laval, Québec City, QC, G1V 0A6, Canada
- Université Laval Cancer Research Center, Université Laval, Quebec City, QC, G1R 3S3, Canada
| | - Élise G Lavoie
- Oncology Division, Centre Hospitalier Universitaire (CHU) de Québec-Université Laval Research Center, Quebec City, QC, G1R 2J6, Canada
- Université Laval Cancer Research Center, Université Laval, Quebec City, QC, G1R 3S3, Canada
| | - Andréanne Blondeau
- Oncology Division, Centre Hospitalier Universitaire (CHU) de Québec-Université Laval Research Center, Quebec City, QC, G1R 2J6, Canada
- Université Laval Cancer Research Center, Université Laval, Quebec City, QC, G1R 3S3, Canada
| | - Annie Gravel
- Division of Infectious Disease and Immunity, Centre Hospitalier Universitaire (CHU) de Québec-Université Laval Research Center, Quebec City, QC, G1V 4G2, Canada
- Department of Microbiology, Infectious Disease and Immunology, Faculty of Medicine, Université Laval, Quebec City, QC, G1V 0A6, Canada
| | - Maxime Galloy
- Oncology Division, Centre Hospitalier Universitaire (CHU) de Québec-Université Laval Research Center, Quebec City, QC, G1R 2J6, Canada
- Department of Molecular biology, Medical Biochemistry and Pathology, Faculty of Medicine, Université Laval, Québec City, QC, G1V 0A6, Canada
- Université Laval Cancer Research Center, Université Laval, Quebec City, QC, G1R 3S3, Canada
| | - Anahita Lashgari
- Oncology Division, Centre Hospitalier Universitaire (CHU) de Québec-Université Laval Research Center, Quebec City, QC, G1R 2J6, Canada
- Department of Molecular biology, Medical Biochemistry and Pathology, Faculty of Medicine, Université Laval, Québec City, QC, G1V 0A6, Canada
- Université Laval Cancer Research Center, Université Laval, Quebec City, QC, G1R 3S3, Canada
| | - Julien Dessapt
- Oncology Division, Centre Hospitalier Universitaire (CHU) de Québec-Université Laval Research Center, Quebec City, QC, G1R 2J6, Canada
- Department of Molecular biology, Medical Biochemistry and Pathology, Faculty of Medicine, Université Laval, Québec City, QC, G1V 0A6, Canada
- Université Laval Cancer Research Center, Université Laval, Quebec City, QC, G1R 3S3, Canada
| | - Jacques Côté
- Oncology Division, Centre Hospitalier Universitaire (CHU) de Québec-Université Laval Research Center, Quebec City, QC, G1R 2J6, Canada
- Department of Molecular biology, Medical Biochemistry and Pathology, Faculty of Medicine, Université Laval, Québec City, QC, G1V 0A6, Canada
- Université Laval Cancer Research Center, Université Laval, Quebec City, QC, G1R 3S3, Canada
| | - Louis Flamand
- Division of Infectious Disease and Immunity, Centre Hospitalier Universitaire (CHU) de Québec-Université Laval Research Center, Quebec City, QC, G1V 4G2, Canada.
- Department of Microbiology, Infectious Disease and Immunology, Faculty of Medicine, Université Laval, Quebec City, QC, G1V 0A6, Canada.
| | - Amélie Fradet-Turcotte
- Oncology Division, Centre Hospitalier Universitaire (CHU) de Québec-Université Laval Research Center, Quebec City, QC, G1R 2J6, Canada.
- Department of Molecular biology, Medical Biochemistry and Pathology, Faculty of Medicine, Université Laval, Québec City, QC, G1V 0A6, Canada.
- Université Laval Cancer Research Center, Université Laval, Quebec City, QC, G1R 3S3, Canada.
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Bournaka S, Badra-Fajardo N, Arbi M, Taraviras S, Lygerou Z. The cell cycle revisited: DNA replication past S phase preserves genome integrity. Semin Cancer Biol 2024; 99:45-55. [PMID: 38346544 DOI: 10.1016/j.semcancer.2024.02.002] [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: 11/27/2023] [Revised: 01/23/2024] [Accepted: 02/05/2024] [Indexed: 02/20/2024]
Abstract
Accurate and complete DNA duplication is critical for maintaining genome integrity. Multiple mechanisms regulate when and where DNA replication takes place, to ensure that the entire genome is duplicated once and only once per cell cycle. Although the bulk of the genome is copied during the S phase of the cell cycle, increasing evidence suggests that parts of the genome are replicated in G2 or mitosis, in a last attempt to secure that daughter cells inherit an accurate copy of parental DNA. Remaining unreplicated gaps may be passed down to progeny and replicated in the next G1 or S phase. These findings challenge the long-established view that genome duplication occurs strictly during the S phase, bridging DNA replication to DNA repair and providing novel therapeutic strategies for cancer treatment.
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Affiliation(s)
- Spyridoula Bournaka
- Department of General Biology, Medical School, University of Patras, Patras 26504, Greece
| | - Nibal Badra-Fajardo
- Department of General Biology, Medical School, University of Patras, Patras 26504, Greece
| | - Marina Arbi
- Department of General Biology, Medical School, University of Patras, Patras 26504, Greece
| | - Stavros Taraviras
- Department of Physiology, Medical School, University of Patras, Patras 26504, Greece
| | - Zoi Lygerou
- Department of General Biology, Medical School, University of Patras, Patras 26504, Greece.
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19
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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: 6] [Impact Index Per Article: 6.0] [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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20
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Zhu YX, He M, Li KJ, Wang YK, Qian N, Wang ZF, Sheng H, Sui Y, Zhang DD, Zhang K, Qi L, Zheng DQ. Novel insights into the effects of 5-hydroxymethfurural on genomic instability and phenotypic evolution using a yeast model. Appl Environ Microbiol 2024; 90:e0164923. [PMID: 38108644 PMCID: PMC10807415 DOI: 10.1128/aem.01649-23] [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: 09/19/2023] [Accepted: 11/06/2023] [Indexed: 12/19/2023] Open
Abstract
5-Hydroxymethfurural (5-HMF) is naturally found in a variety of foods and beverages and represents a main inhibitor in the lignocellulosic hydrolysates used for fermentation. This study investigated the impact of 5-HMF on the genomic stability and phenotypic plasticity of the yeast Saccharomyces cerevisiae. Using next-generation sequencing technology, we examined the genomic alterations of diploid S. cerevisiae isolates that were subcultured on a medium containing 1.2 g/L 5-HMF. We found that in 5-HMF-treated cells, the rates of chromosome aneuploidy, large deletions/duplications, and loss of heterozygosity were elevated compared with that in untreated cells. 5-HMF exposure had a mild impact on the rate of point mutations but altered the mutation spectrum. Contrary to what was observed in untreated cells, more monosomy than trisomy occurred in 5-HMF-treated cells. The aneuploidy mutant with monosomic chromosome IX was more resistant to 5-HMF than the diploid parent strain because of the enhanced activity of alcohol dehydrogenase. Finally, we found that overexpression of ADH6 and ZWF1 effectively stabilized the yeast genome under 5-HMF stress. Our findings not only elucidated the global effect of 5-HMF on the genomic integrity of yeast but also provided novel insights into how chromosomal instability drives the environmental adaptability of eukaryotic cells.IMPORTANCESingle-cell microorganisms are exposed to a range of stressors in both natural and industrial settings. This study investigated the effects of 5-hydroxymethfurural (5-HMF), a major inhibitor found in baked foods and lignocellulosic hydrolysates, on the chromosomal instability of yeast. We examined the mechanisms leading to the distinct patterns of 5-HMF-induced genomic alterations and discovered that chromosomal loss, typically viewed as detrimental to cell growth under most conditions, can contribute to yeast tolerance to 5-HMF. Our results increased the understanding of how specific stressors stimulate genomic plasticity and environmental adaptation in yeast.
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Affiliation(s)
- Ying-Xuan Zhu
- Hainan Institute of Zhejiang University, Zhejiang University, Sanya, China
- Ocean College, Zhejiang University, Zhoushan, China
| | - Min He
- Hainan Institute of Zhejiang University, Zhejiang University, Sanya, China
| | - Ke-Jing Li
- Ocean College, Zhejiang University, Zhoushan, China
| | - Ye-Ke Wang
- College of Life Science, Zhejiang University, Hangzhou, China
| | - Ning Qian
- Ocean College, Zhejiang University, Zhoushan, China
| | - Ze-Fei Wang
- Hainan Institute of Zhejiang University, Zhejiang University, Sanya, China
| | - Huan Sheng
- Ocean College, Zhejiang University, Zhoushan, China
| | - Yang Sui
- Ocean College, Zhejiang University, Zhoushan, China
| | | | - Ke Zhang
- College of Life Science, Zhejiang University, Hangzhou, China
| | - Lei Qi
- Ocean College, Zhejiang University, Zhoushan, China
| | - Dao-Qiong Zheng
- Hainan Institute of Zhejiang University, Zhejiang University, Sanya, China
- Ocean College, Zhejiang University, Zhoushan, China
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21
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Mórocz M, Qorri E, Pekker E, Tick G, Haracska L. Exploring RAD18-dependent replication of damaged DNA and discontinuities: A collection of advanced tools. J Biotechnol 2024; 380:1-19. [PMID: 38072328 DOI: 10.1016/j.jbiotec.2023.12.001] [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: 10/11/2023] [Revised: 12/01/2023] [Accepted: 12/03/2023] [Indexed: 12/21/2023]
Abstract
DNA damage tolerance (DDT) pathways mitigate the effects of DNA damage during replication by rescuing the replication fork stalled at a DNA lesion or other barriers and also repair discontinuities left in the newly replicated DNA. From yeast to mammalian cells, RAD18-regulated translesion synthesis (TLS) and template switching (TS) represent the dominant pathways of DDT. Monoubiquitylation of the polymerase sliding clamp PCNA by HRAD6A-B/RAD18, an E2/E3 protein pair, enables the recruitment of specialized TLS polymerases that can insert nucleotides opposite damaged template bases. Alternatively, the subsequent polyubiquitylation of monoubiquitin-PCNA by Ubc13-Mms2 (E2) and HLTF or SHPRH (E3) can lead to the switching of the synthesis from the damaged template to the undamaged newly synthesized sister strand to facilitate synthesis past the lesion. When immediate TLS or TS cannot occur, gaps may remain in the newly synthesized strand, partly due to the repriming activity of the PRIMPOL primase, which can be filled during the later phases of the cell cycle. The first part of this review will summarize the current knowledge about RAD18-dependent DDT pathways, while the second part will offer a molecular toolkit for the identification and characterization of the cellular functions of a DDT protein. In particular, we will focus on advanced techniques that can reveal single-stranded and double-stranded DNA gaps and their repair at the single-cell level as well as monitor the progression of single replication forks, such as the specific versions of the DNA fiber and comet assays. This collection of methods may serve as a powerful molecular toolkit to monitor the metabolism of gaps, detect the contribution of relevant pathways and molecular players, as well as characterize the effectiveness of potential inhibitors.
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Affiliation(s)
- Mónika Mórocz
- HCEMM-HUN-REN BRC Mutagenesis and Carcinogenesis Research Group, HUN-REN Biological Research Centre, Szeged H-6726, Hungary.
| | - Erda Qorri
- HCEMM-HUN-REN BRC Mutagenesis and Carcinogenesis Research Group, HUN-REN Biological Research Centre, Szeged H-6726, Hungary; Faculty of Science and Informatics, Doctoral School of Biology, University of Szeged, Szeged H-6720, Hungary.
| | - Emese Pekker
- HCEMM-HUN-REN BRC Mutagenesis and Carcinogenesis Research Group, HUN-REN Biological Research Centre, Szeged H-6726, Hungary; Doctoral School of Interdisciplinary Medicine, University of Szeged, Korányi fasor 10, 6720 Szeged, Hungary.
| | - Gabriella Tick
- Mutagenesis and Carcinogenesis Research Group, HUN-REN Biological Research Centre, Szeged H-6726, Hungary.
| | - Lajos Haracska
- HCEMM-HUN-REN BRC Mutagenesis and Carcinogenesis Research Group, HUN-REN Biological Research Centre, Szeged H-6726, Hungary; National Laboratory for Drug Research and Development, Magyar tudósok krt. 2. H-1117 Budapest, Hungary.
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22
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Gadgil RY, Rider SD, Shrestha R, Alhawach V, Hitch DC, Leffak M. Microsatellite break-induced replication generates highly mutagenized extrachromosomal circular DNAs. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.01.12.575055. [PMID: 38260482 PMCID: PMC10802558 DOI: 10.1101/2024.01.12.575055] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2024]
Abstract
Extrachromosomal circular DNAs (eccDNAs) are produced from all regions of the eucaryotic genome. In tumors, highly transcribed eccDNAs have been implicated in oncogenesis, neoantigen production and resistance to chemotherapy. Here we show that unstable microsatellites capable of forming hairpin, triplex, quadruplex and AT-rich structures generate eccDNAs when integrated at a common ectopic site in human cells. These non-B DNA prone microsatellites form eccDNAs by replication-dependent mechanisms. The microsatellite-based eccDNAs are highly mutagenized and display template switches to sister chromatids and to nonallelic chromosomal sites. High frequency mutagenesis occurs within the eccDNA microsatellites and extends bidirectionally for several kilobases into flanking DNA and nonallelic DNA. Mutations include mismatches, short duplications, longer nontemplated insertions and large deletions. Template switching leads to recurrent deletions and recombination domains within the eccDNAs. Template switching events are microhomology-mediated, but do not occur at all potential sites of complementarity. Each microsatellite exhibits a distinct pattern of recombination, microhomology choice and base substitution signature. Depletion of Rad51, the COPS2 signalosome subunit or POLη alter the eccDNA mutagenic profiles. We propose an asynchronous capture model based on break-induced replication from microsatellite-induced DNA breaks for the generation and circularization of mutagenized eccDNAs and genomic homologous recombination deficiency (HRD) scars.
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23
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Spegg V, Altmeyer M. Genome maintenance meets mechanobiology. Chromosoma 2024; 133:15-36. [PMID: 37581649 PMCID: PMC10904543 DOI: 10.1007/s00412-023-00807-5] [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: 04/04/2023] [Revised: 06/20/2023] [Accepted: 07/26/2023] [Indexed: 08/16/2023]
Abstract
Genome stability is key for healthy cells in healthy organisms, and deregulated maintenance of genome integrity is a hallmark of aging and of age-associated diseases including cancer and neurodegeneration. To maintain a stable genome, genome surveillance and repair pathways are closely intertwined with cell cycle regulation and with DNA transactions that occur during transcription and DNA replication. Coordination of these processes across different time and length scales involves dynamic changes of chromatin topology, clustering of fragile genomic regions and repair factors into nuclear repair centers, mobilization of the nuclear cytoskeleton, and activation of cell cycle checkpoints. Here, we provide a general overview of cell cycle regulation and of the processes involved in genome duplication in human cells, followed by an introduction to replication stress and to the cellular responses elicited by perturbed DNA synthesis. We discuss fragile genomic regions that experience high levels of replication stress, with a particular focus on telomere fragility caused by replication stress at the ends of linear chromosomes. Using alternative lengthening of telomeres (ALT) in cancer cells and ALT-associated PML bodies (APBs) as examples of replication stress-associated clustered DNA damage, we discuss compartmentalization of DNA repair reactions and the role of protein properties implicated in phase separation. Finally, we highlight emerging connections between DNA repair and mechanobiology and discuss how biomolecular condensates, components of the nuclear cytoskeleton, and interfaces between membrane-bound organelles and membraneless macromolecular condensates may cooperate to coordinate genome maintenance in space and time.
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Affiliation(s)
- Vincent Spegg
- Department of Molecular Mechanisms of Disease, University of Zurich, Zurich, Switzerland
| | - Matthias Altmeyer
- Department of Molecular Mechanisms of Disease, University of Zurich, Zurich, Switzerland.
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24
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Lim J, Kim W, Kim J, Lee J. Telomeric repeat evolution in the phylum Nematoda revealed by high-quality genome assemblies and subtelomere structures. Genome Res 2023; 33:1947-1957. [PMID: 37918961 PMCID: PMC10760449 DOI: 10.1101/gr.278124.123] [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: 05/24/2023] [Accepted: 10/16/2023] [Indexed: 11/04/2023]
Abstract
Telomeres are composed of tandem arrays of telomeric-repeat motifs (TRMs) and telomere-binding proteins (TBPs), which are responsible for ensuring end-protection and end-replication of chromosomes. TRMs are highly conserved owing to the sequence specificity of TBPs, although significant alterations in TRM have been observed in several taxa, except Nematoda. We used public whole-genome sequencing data sets to analyze putative TRMs of 100 nematode species and determined that three distinct branches included specific novel TRMs, suggesting that evolutionary alterations in TRMs occurred in Nematoda. We focused on one of the three branches, the Panagrolaimidae family, and performed a de novo assembly of four high-quality draft genomes of the canonical (TTAGGC) and novel TRM (TTAGAC) isolates; the latter genomes revealed densely clustered arrays of the novel TRM. We then comprehensively analyzed the subtelomeric regions of the genomes to infer how the novel TRM evolved. We identified DNA damage-repair signatures in subtelomeric sequences that were representative of consequences of telomere maintenance mechanisms by alternative lengthening of telomeres. We propose a hypothetical scenario in which TTAGAC-containing units are clustered in subtelomeric regions and pre-existing TBPs capable of binding both canonical and novel TRMs aided the evolution of the novel TRM in the Panagrolaimidae family.
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Affiliation(s)
- Jiseon Lim
- Department of Biological Sciences, Seoul National University, Gwanak-gu, Seoul 08826, South Korea
- Institute of Molecular Biology and Genetics, Seoul National University, Seoul 08826, South Korea
| | - Wonjoo Kim
- Department of Biological Sciences, Seoul National University, Gwanak-gu, Seoul 08826, South Korea
- Institute of Molecular Biology and Genetics, Seoul National University, Seoul 08826, South Korea
| | - Jun Kim
- Department of Biological Sciences, Seoul National University, Gwanak-gu, Seoul 08826, South Korea;
- Research Institute of Basic Sciences, Seoul National University, Seoul 08826, South Korea
- Department of Convergent Bioscience and Informatics, College of Bioscience and Biotechnology, Chungnam National University, Daejeon 34134, South Korea
| | - Junho Lee
- Department of Biological Sciences, Seoul National University, Gwanak-gu, Seoul 08826, South Korea
- Institute of Molecular Biology and Genetics, Seoul National University, Seoul 08826, South Korea
- Research Institute of Basic Sciences, Seoul National University, Seoul 08826, South Korea
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25
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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: 4] [Impact Index Per Article: 4.0] [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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26
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Hu J, Ferlez B, Dau J, Crickard JB. Rad53 regulates the lifetime of Rdh54 at homologous recombination intermediates. Nucleic Acids Res 2023; 51:11688-11705. [PMID: 37850655 PMCID: PMC10681728 DOI: 10.1093/nar/gkad848] [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: 05/22/2023] [Revised: 09/12/2023] [Accepted: 09/21/2023] [Indexed: 10/19/2023] Open
Abstract
Rdh54 is a conserved DNA translocase that participates in homologous recombination (HR), DNA checkpoint adaptation, and chromosome segregation. Saccharomyces cerevisiae Rdh54 is a known target of the Mec1/Rad53 signaling axis, which globally protects genome integrity during DNA metabolism. While phosphorylation of DNA repair proteins by Mec1/Rad53 is critical for HR progression little is known about how specific post translational modifications alter HR reactions. Phosphorylation of Rdh54 is linked to protection of genomic integrity but the consequences of modification remain poorly understood. Here, we demonstrate that phosphorylation of the Rdh54 C-terminus by the effector kinase Rad53 regulates Rdh54 clustering activity as revealed by single molecule imaging. This stems from phosphorylation dependent and independent interactions between Rdh54 and Rad53. Genetic assays reveal that loss of phosphorylation leads to phenotypic changes resulting in loss-of-heterozygosity (LOH) outcomes. Our data highlight Rad53 as a key regulator of HR intermediates through activation and attenuation of Rdh54 motor function.
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Affiliation(s)
- Jingyi Hu
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14853, USA
| | - Bryan Ferlez
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14853, USA
| | - Jennifer Dau
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14853, USA
| | - J Brooks Crickard
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14853, USA
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27
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Bhowmick R, Hickson ID, Liu Y. Completing genome replication outside of S phase. Mol Cell 2023; 83:3596-3607. [PMID: 37716351 DOI: 10.1016/j.molcel.2023.08.023] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2023] [Revised: 08/03/2023] [Accepted: 08/17/2023] [Indexed: 09/18/2023]
Abstract
Mitotic DNA synthesis (MiDAS) is an unusual form of DNA replication that occurs during mitosis. Initially, MiDAS was characterized as a process associated with intrinsically unstable loci known as common fragile sites that occurs after cells experience DNA replication stress (RS). However, it is now believed to be a more widespread "salvage" mechanism that is called upon to complete the duplication of any under-replicated genomic region. Emerging data suggest that MiDAS is a DNA repair process potentially involving two or more pathways working in parallel or sequentially. In this review, we introduce the causes of RS, regions of the human genome known to be especially vulnerable to RS, and the strategies used to complete DNA replication outside of S phase. Additionally, because MiDAS is a prominent feature of aneuploid cancer cells, we will discuss how targeting MiDAS might potentially lead to improvements in cancer therapy.
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Affiliation(s)
- Rahul Bhowmick
- Center for Chromosome Stability and Center for Healthy Aging, Department of Cellular and Molecular Medicine, University of Copenhagen, Panum Institute, Blegdamsvej 3B, 2200 Copenhagen N, Denmark; Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
| | - Ian D Hickson
- Center for Chromosome Stability and Center for Healthy Aging, Department of Cellular and Molecular Medicine, University of Copenhagen, Panum Institute, Blegdamsvej 3B, 2200 Copenhagen N, Denmark.
| | - Ying Liu
- Center for Chromosome Stability and Center for Healthy Aging, Department of Cellular and Molecular Medicine, University of Copenhagen, Panum Institute, Blegdamsvej 3B, 2200 Copenhagen N, Denmark.
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28
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Kanoh J. Subtelomeres: hotspots of genome variation. Genes Genet Syst 2023; 98:155-160. [PMID: 37648502 DOI: 10.1266/ggs.23-00049] [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] [Indexed: 09/01/2023] Open
Abstract
Eukaryotic cells contain multiple types of duplicated sequences. Typical examples are tandem repeat sequences including telomeres, centromeres, rDNA genes and transposable elements. Most of these sequences are unstable; thus, their copy numbers or sequences change rapidly in the course of evolution. In this review, I will describe roles of subtelomere regions, which are located adjacent to telomeres at chromosome ends, and recent discoveries about their sequence variation.
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Affiliation(s)
- Junko Kanoh
- Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo
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29
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Desilets A, Repetto M, Yang SR, Sherman EJ, Drilon A. RET-Altered Cancers-A Tumor-Agnostic Review of Biology, Diagnosis and Targeted Therapy Activity. Cancers (Basel) 2023; 15:4146. [PMID: 37627175 PMCID: PMC10452615 DOI: 10.3390/cancers15164146] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2023] [Revised: 08/11/2023] [Accepted: 08/12/2023] [Indexed: 08/27/2023] Open
Abstract
RET alterations, such as fusions or mutations, drive the growth of multiple tumor types. These alterations are found in canonical (lung and thyroid) and non-canonical (e.g., gastrointestinal, breast, gynecological, genitourinary, histiocytic) cancers. RET alterations are best identified via comprehensive next-generation sequencing, preferably with DNA and RNA interrogation for fusions. Targeted therapies for RET-dependent cancers have evolved from older multikinase inhibitors to selective inhibitors of RET such as selpercatinib and pralsetinib. Prospective basket trials and retrospective reports have demonstrated the activity of these drugs in a wide variety of RET-altered cancers, notably those with RET fusions. This paved the way for the first tumor-agnostic selective RET inhibitor US FDA approval in 2022. Acquired resistance to RET kinase inhibitors can take the form of acquired resistance mutations (e.g., RET G810X) or bypass alterations.
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Affiliation(s)
- Antoine Desilets
- Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA; (A.D.); (M.R.); (S.-R.Y.); (E.J.S.)
| | - Matteo Repetto
- Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA; (A.D.); (M.R.); (S.-R.Y.); (E.J.S.)
- Department of Oncology and Hemato-Oncology, University of Milan, 20133 Milan, Italy
| | - Soo-Ryum Yang
- Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA; (A.D.); (M.R.); (S.-R.Y.); (E.J.S.)
| | - Eric J. Sherman
- Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA; (A.D.); (M.R.); (S.-R.Y.); (E.J.S.)
- Department of Medicine, Weill Cornell Medical College, New York, NY 10065, USA
| | - Alexander Drilon
- Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA; (A.D.); (M.R.); (S.-R.Y.); (E.J.S.)
- Department of Medicine, Weill Cornell Medical College, New York, NY 10065, USA
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30
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Qi L, Zhu YX, Wang YK, Tang XX, Li KJ, He M, Sui Y, Wang PM, Zheng DQ, Zhang K. Nonlethal Furfural Exposure Causes Genomic Alterations and Adaptability Evolution in Saccharomyces cerevisiae. Microbiol Spectr 2023; 11:e0121623. [PMID: 37395645 PMCID: PMC10434202 DOI: 10.1128/spectrum.01216-23] [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: 03/20/2023] [Accepted: 06/09/2023] [Indexed: 07/04/2023] Open
Abstract
Furfural is a major inhibitor found in lignocellulosic hydrolysate, a promising feedstock for the biofermentation industry. In this study, we aimed to investigate the potential impact of this furan-derived chemical on yeast genome integrity and phenotypic evolution by using genetic screening systems and high-throughput analyses. Our results showed that the rates of aneuploidy, chromosomal rearrangements (including large deletions and duplications), and loss of heterozygosity (LOH) increased by 50-fold, 23-fold, and 4-fold, respectively, when yeast cells were cultured in medium containing a nonlethal dose of furfural (0.6 g/L). We observed significantly different ratios of genetic events between untreated and furfural-exposed cells, indicating that furfural exposure induced a unique pattern of genomic instability. Furfural exposure also increased the proportion of CG-to-TA and CG-to-AT base substitutions among point mutations, which was correlated with DNA oxidative damage. Interestingly, although monosomy of chromosomes often results in the slower growth of yeast under spontaneous conditions, we found that monosomic chromosome IX contributed to the enhanced furfural tolerance. Additionally, terminal LOH events on the right arm of chromosome IV, which led to homozygosity of the SSD1 allele, were associated with furfural resistance. This study sheds light on the mechanisms underlying the influence of furfural on yeast genome integrity and adaptability evolution. IMPORTANCE Industrial microorganisms are often exposed to multiple environmental stressors and inhibitors during their application. This study demonstrates that nonlethal concentrations of furfural in the culture medium can significantly induce genome instability in the yeast Saccharomyces cerevisiae. Notably, furfural-exposed yeast cells displayed frequent chromosome aberrations, indicating the potent teratogenicity of this inhibitor. We identified specific genomic alterations, including monosomic chromosome IX and loss of heterozygosity of the right arm of chromosome IV, that confer furfural tolerance to a diploid S. cerevisiae strain. These findings enhance our understanding of how microorganisms evolve and adapt to stressful environments and offer insights for developing strategies to improve their performance in industrial applications.
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Affiliation(s)
- Lei Qi
- Donghai Laboratory, Zhoushan, China
- Ocean College, Zhejiang University, Zhoushan, China
- Department of Molecular Genetics and Microbiology, Duke University, Durham, North Carolina, USA
| | | | - Ye-Ke Wang
- Life Sciences Institute, Zhejiang University, Hangzhou, China
| | | | - Ke-Jing Li
- Ocean College, Zhejiang University, Zhoushan, China
| | - Min He
- Ocean College, Zhejiang University, Zhoushan, China
| | - Yang Sui
- Donghai Laboratory, Zhoushan, China
- Department of Molecular Genetics and Microbiology, Duke University, Durham, North Carolina, USA
| | - Pin-Mei Wang
- Donghai Laboratory, Zhoushan, China
- Ocean College, Zhejiang University, Zhoushan, China
| | - Dao-Qiong Zheng
- Donghai Laboratory, Zhoushan, China
- Ocean College, Zhejiang University, Zhoushan, China
| | - Ke Zhang
- College of Life Science, Zhejiang University, Hangzhou, China
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31
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Wang X, Zhang S, Zhang Z, Mazloum NA, Lee EYC, Lee MYW. The DHX9 helicase interacts with human DNA polymerase δ4 and stimulates its activity in D-loop extension synthesis. DNA Repair (Amst) 2023; 128:103513. [PMID: 37285751 PMCID: PMC10330758 DOI: 10.1016/j.dnarep.2023.103513] [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: 03/08/2023] [Revised: 04/28/2023] [Accepted: 05/11/2023] [Indexed: 06/09/2023]
Abstract
The extension of the invading strand within a displacement loop (D-loop) is a key step in homology directed repair (HDR) of doubled stranded DNA breaks. The primary goal of these studies was to test the hypotheses that 1) D-loop extension by human DNA polymerase δ4 (Pol δ4) is facilitated by DHX9, a 3' to 5' motor helicase, which acts to unwind the leading edge of the D-loop, and 2) the recruitment of DHX9 is mediated by direct protein-protein interactions between DHX9 and Pol δ4 and/or PCNA. DNA synthesis by Pol δ4 was analyzed in a reconstitution assay by the extension of a 93mer oligonucleotide inserted into a plasmid to form a D-loop. Product formation by Pol δ4 was monitored by incorporation of [α-32P]dNTPs into the 93mer primer followed by denaturing gel electrophoresis. The results showed that DHX9 strongly stimulated Pol δ4 mediated D-loop extension. Direct interactions of DHX9 with PCNA, the p125 and the p12 subunits of Pol δ4 were demonstrated by pull-down assays with purified proteins. These data support the hypothesis that DHX9 helicase is recruited by Pol δ4/PCNA to facilitate D-loop synthesis in HDR, and is a participant in cellular HDR. The involvement of DHX9 in HDR represents an important addition to its multiple cellular roles. Such helicase-polymerase interactions may represent an important aspect of the mechanisms involved in D-loop primer extension synthesis in HDR.
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Affiliation(s)
- Xiaoxiao Wang
- Department of Biochemistry and Molecular Biology, New York Medical College, 15 Dana Road, Valhalla, NY 10595, USA
| | - Sufang Zhang
- Department of Biochemistry and Molecular Biology, New York Medical College, 15 Dana Road, Valhalla, NY 10595, USA
| | - Zhongtao Zhang
- Department of Biochemistry and Molecular Biology, New York Medical College, 15 Dana Road, Valhalla, NY 10595, USA
| | - Nayef A Mazloum
- Department of Biochemistry and Molecular Biology, New York Medical College, 15 Dana Road, Valhalla, NY 10595, USA
| | - Ernest Y C Lee
- Department of Biochemistry and Molecular Biology, New York Medical College, 15 Dana Road, Valhalla, NY 10595, USA
| | - Marietta Y W Lee
- Department of Biochemistry and Molecular Biology, New York Medical College, 15 Dana Road, Valhalla, NY 10595, USA.
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32
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Stepchenkova EI, Zadorsky SP, Shumega AR, Aksenova AY. Practical Approaches for the Yeast Saccharomyces cerevisiae Genome Modification. Int J Mol Sci 2023; 24:11960. [PMID: 37569333 PMCID: PMC10419131 DOI: 10.3390/ijms241511960] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2023] [Revised: 07/21/2023] [Accepted: 07/22/2023] [Indexed: 08/13/2023] Open
Abstract
The yeast S. cerevisiae is a unique genetic object for which a wide range of relatively simple, inexpensive, and non-time-consuming methods have been developed that allow the performing of a wide variety of genome modifications. Among the latter, one can mention point mutations, disruptions and deletions of particular genes and regions of chromosomes, insertion of cassettes for the expression of heterologous genes, targeted chromosomal rearrangements such as translocations and inversions, directed changes in the karyotype (loss or duplication of particular chromosomes, changes in the level of ploidy), mating-type changes, etc. Classical yeast genome manipulations have been advanced with CRISPR/Cas9 technology in recent years that allow for the generation of multiple simultaneous changes in the yeast genome. In this review we discuss practical applications of both the classical yeast genome modification methods as well as CRISPR/Cas9 technology. In addition, we review methods for ploidy changes, including aneuploid generation, methods for mating type switching and directed DSB. Combined with a description of useful selective markers and transformation techniques, this work represents a nearly complete guide to yeast genome modification.
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Affiliation(s)
- Elena I. Stepchenkova
- Department of Genetics and Biotechnology, St. Petersburg State University, 199034 St. Petersburg, Russia; (E.I.S.); (S.P.Z.); (A.R.S.)
- Vavilov Institute of General Genetics, St. Petersburg Branch, Russian Academy of Sciences, 199034 St. Petersburg, Russia
| | - Sergey P. Zadorsky
- Department of Genetics and Biotechnology, St. Petersburg State University, 199034 St. Petersburg, Russia; (E.I.S.); (S.P.Z.); (A.R.S.)
- Vavilov Institute of General Genetics, St. Petersburg Branch, Russian Academy of Sciences, 199034 St. Petersburg, Russia
| | - Andrey R. Shumega
- Department of Genetics and Biotechnology, St. Petersburg State University, 199034 St. Petersburg, Russia; (E.I.S.); (S.P.Z.); (A.R.S.)
| | - Anna Y. Aksenova
- Laboratory of Amyloid Biology, St. Petersburg State University, 199034 St. Petersburg, Russia
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33
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Richards F, Llorca-Cardenosa MJ, Langton J, Buch-Larsen SC, Shamkhi NF, Sharma AB, Nielsen ML, Lakin ND. Regulation of Rad52-dependent replication fork recovery through serine ADP-ribosylation of PolD3. Nat Commun 2023; 14:4310. [PMID: 37463936 DOI: 10.1038/s41467-023-40071-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2022] [Accepted: 07/06/2023] [Indexed: 07/20/2023] Open
Abstract
Although Poly(ADP-ribose)-polymerases (PARPs) are key regulators of genome stability, how site-specific ADP-ribosylation regulates DNA repair is unclear. Here, we describe a novel role for PARP1 and PARP2 in regulating Rad52-dependent replication fork repair to maintain cell viability when homologous recombination is dysfunctional, suppress replication-associated DNA damage, and maintain genome stability. Mechanistically, Mre11 and ATM are required for induction of PARP activity in response to replication stress that in turn promotes break-induced replication (BIR) through assembly of Rad52 at stalled/damaged replication forks. Further, by mapping ADP-ribosylation sites induced upon replication stress, we identify that PolD3 is a target for PARP1/PARP2 and that its site-specific ADP-ribosylation is required for BIR activity, replication fork recovery and genome stability. Overall, these data identify a critical role for Mre11-dependent PARP activation and site-specific ADP-ribosylation in regulating BIR to maintain genome integrity during DNA synthesis.
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Affiliation(s)
- Frederick Richards
- Department of Biochemistry, University of Oxford, South Parks Road, Oxford, UK
| | | | - Jamie Langton
- Department of Biochemistry, University of Oxford, South Parks Road, Oxford, UK
| | - Sara C Buch-Larsen
- Novo Nordisk Foundation Centre for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3B, 2200, Copenhagen, Denmark
| | - Noor F Shamkhi
- Department of Biochemistry, University of Oxford, South Parks Road, Oxford, UK
| | | | - Michael L Nielsen
- Novo Nordisk Foundation Centre for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3B, 2200, Copenhagen, Denmark
| | - Nicholas D Lakin
- Department of Biochemistry, University of Oxford, South Parks Road, Oxford, UK.
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34
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Cullot G, Boutin J, Fayet S, Prat F, Rosier J, Cappellen D, Lamrissi I, Pennamen P, Bouron J, Amintas S, Thibault C, Moranvillier I, Laharanne E, Merlio JP, Guyonnet-Duperat V, Blouin JM, Richard E, Dabernat S, Moreau-Gaudry F, Bedel A. Cell cycle arrest and p53 prevent ON-target megabase-scale rearrangements induced by CRISPR-Cas9. Nat Commun 2023; 14:4072. [PMID: 37429857 DOI: 10.1038/s41467-023-39632-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2022] [Accepted: 06/22/2023] [Indexed: 07/12/2023] Open
Abstract
The CRISPR-Cas9 system has revolutionized our ability to precisely modify the genome and has led to gene editing in clinical applications. Comprehensive analysis of gene editing products at the targeted cut-site has revealed a complex spectrum of outcomes. ON-target genotoxicity is underestimated with standard PCR-based methods and necessitates appropriate and more sensitive detection methods. Here, we present two complementary Fluorescence-Assisted Megabase-scale Rearrangements Detection (FAMReD) systems that enable the detection, quantification, and cell sorting of edited cells with megabase-scale loss of heterozygosity (LOH). These tools reveal rare complex chromosomal rearrangements caused by Cas9-nuclease and show that LOH frequency depends on cell division rate during editing and p53 status. Cell cycle arrest during editing suppresses the occurrence of LOH without compromising editing. These data are confirmed in human stem/progenitor cells, suggesting that clinical trials should consider p53 status and cell proliferation rate during editing to limit this risk by designing safer protocols.
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Affiliation(s)
- G Cullot
- Bordeaux University, INSERM, BRIC, U1312, F-33000, Bordeaux, France
| | - J Boutin
- Bordeaux University, INSERM, BRIC, U1312, F-33000, Bordeaux, France
- CHU de Bordeaux, Biochemistry Laboratory, F-33000, Bordeaux, France
| | - S Fayet
- Bordeaux University, INSERM, BRIC, U1312, F-33000, Bordeaux, France
| | - F Prat
- Bordeaux University, INSERM, BRIC, U1312, F-33000, Bordeaux, France
| | - J Rosier
- Bordeaux University, INSERM, BRIC, U1312, F-33000, Bordeaux, France
| | - D Cappellen
- Bordeaux University, INSERM, BRIC, U1312, F-33000, Bordeaux, France
- CHU de Bordeaux, Tumor Biology and Tumor Bank Laboratory, F-33000, Bordeaux, France
| | - I Lamrissi
- Bordeaux University, INSERM, BRIC, U1312, F-33000, Bordeaux, France
| | - P Pennamen
- CHU de Bordeaux, department of medical genetics, F-33000, Bordeaux, France
| | - J Bouron
- CHU de Bordeaux, department of medical genetics, F-33000, Bordeaux, France
| | - S Amintas
- Bordeaux University, INSERM, BRIC, U1312, F-33000, Bordeaux, France
- CHU de Bordeaux, Tumor Biology and Tumor Bank Laboratory, F-33000, Bordeaux, France
| | - C Thibault
- Bordeaux University, INSERM, BRIC, U1312, F-33000, Bordeaux, France
| | - I Moranvillier
- Bordeaux University, INSERM, BRIC, U1312, F-33000, Bordeaux, France
| | - E Laharanne
- CHU de Bordeaux, Tumor Biology and Tumor Bank Laboratory, F-33000, Bordeaux, France
| | - J P Merlio
- Bordeaux University, INSERM, BRIC, U1312, F-33000, Bordeaux, France
- CHU de Bordeaux, Tumor Biology and Tumor Bank Laboratory, F-33000, Bordeaux, France
| | - V Guyonnet-Duperat
- Bordeaux University, INSERM, BRIC, U1312, F-33000, Bordeaux, France
- Vect'UB, vectorology platform, INSERM US 005-CNRS UAR 3427-TBM-Core, Bordeaux university, Bordeaux, France
| | - J M Blouin
- Bordeaux University, INSERM, BRIC, U1312, F-33000, Bordeaux, France
- CHU de Bordeaux, Biochemistry Laboratory, F-33000, Bordeaux, France
| | - E Richard
- Bordeaux University, INSERM, BRIC, U1312, F-33000, Bordeaux, France
- CHU de Bordeaux, Biochemistry Laboratory, F-33000, Bordeaux, France
| | - S Dabernat
- Bordeaux University, INSERM, BRIC, U1312, F-33000, Bordeaux, France
- CHU de Bordeaux, Biochemistry Laboratory, F-33000, Bordeaux, France
| | - F Moreau-Gaudry
- Bordeaux University, INSERM, BRIC, U1312, F-33000, Bordeaux, France.
- CHU de Bordeaux, Biochemistry Laboratory, F-33000, Bordeaux, France.
| | - A Bedel
- Bordeaux University, INSERM, BRIC, U1312, F-33000, Bordeaux, France.
- CHU de Bordeaux, Biochemistry Laboratory, F-33000, Bordeaux, France.
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35
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Zhang T, Rawal Y, Jiang H, Kwon Y, Sung P, Greenberg RA. Break-induced replication orchestrates resection-dependent template switching. Nature 2023; 619:201-208. [PMID: 37316655 PMCID: PMC10937050 DOI: 10.1038/s41586-023-06177-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2022] [Accepted: 05/05/2023] [Indexed: 06/16/2023]
Abstract
Break-induced telomere synthesis (BITS) is a RAD51-independent form of break-induced replication that contributes to alternative lengthening of telomeres1,2. This homology-directed repair mechanism utilizes a minimal replisome comprising proliferating cell nuclear antigen (PCNA) and DNA polymerase-δ to execute conservative DNA repair synthesis over many kilobases. How this long-tract homologous recombination repair synthesis responds to complex secondary DNA structures that elicit replication stress remains unclear3-5. Moreover, whether the break-induced replisome orchestrates additional DNA repair events to ensure processivity is also unclear. Here we combine synchronous double-strand break induction with proteomics of isolated chromatin segments (PICh) to capture the telomeric DNA damage response proteome during BITS1,6. This approach revealed a replication stress-dominated response, highlighted by repair synthesis-driven DNA damage tolerance signalling through RAD18-dependent PCNA ubiquitination. Furthermore, the SNM1A nuclease was identified as the major effector of ubiquitinated PCNA-dependent DNA damage tolerance. SNM1A recognizes the ubiquitin-modified break-induced replisome at damaged telomeres, and this directs its nuclease activity to promote resection. These findings show that break-induced replication orchestrates resection-dependent lesion bypass, with SNM1A nuclease activity serving as a critical effector of ubiquitinated PCNA-directed recombination in mammalian cells.
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Affiliation(s)
- Tianpeng Zhang
- Department of Cancer Biology, Penn Center for Genome Integrity, Basser Center for BRCA, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Yashpal Rawal
- Department of Biochemistry and Structural Biology and Greehey Children's Cancer Research Institute, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
| | - Haoyang Jiang
- Department of Cancer Biology, Penn Center for Genome Integrity, Basser Center for BRCA, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Youngho Kwon
- Department of Biochemistry and Structural Biology and Greehey Children's Cancer Research Institute, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
| | - Patrick Sung
- Department of Biochemistry and Structural Biology and Greehey Children's Cancer Research Institute, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
| | - Roger A Greenberg
- Department of Cancer Biology, Penn Center for Genome Integrity, Basser Center for BRCA, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.
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36
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Gan X, Zhang Y, Jiang D, Shi J, Zhao H, Xie C, Wang Y, Xu J, Zhang X, Cai G, Wang H, Huang J, Chen X. Proper RPA acetylation promotes accurate DNA replication and repair. Nucleic Acids Res 2023; 51:5565-5583. [PMID: 37140030 PMCID: PMC10287905 DOI: 10.1093/nar/gkad291] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2023] [Revised: 04/06/2023] [Accepted: 04/12/2023] [Indexed: 05/05/2023] Open
Abstract
The single-stranded DNA (ssDNA) binding protein complex RPA plays a critical role in promoting DNA replication and multiple DNA repair pathways. However, how RPA is regulated to achieve its functions precisely in these processes remains elusive. Here, we found that proper acetylation and deacetylation of RPA are required to regulate RPA function in promoting high-fidelity DNA replication and repair. We show that yeast RPA is acetylated on multiple conserved lysines by the acetyltransferase NuA4 upon DNA damage. Mimicking constitutive RPA acetylation or blocking its acetylation causes spontaneous mutations with the signature of micro-homology-mediated large deletions or insertions. In parallel, improper RPA acetylation/deacetylation impairs DNA double-strand break (DSB) repair by the accurate gene conversion or break-induced replication while increasing the error-prone repair by single-strand annealing or alternative end joining. Mechanistically, we show that proper acetylation and deacetylation of RPA ensure its normal nuclear localization and ssDNA binding ability. Importantly, mutation of the equivalent residues in human RPA1 also impairs RPA binding on ssDNA, leading to attenuated RAD51 loading and homologous recombination repair. Thus, timely RPA acetylation and deacetylation likely represent a conserved mechanism promoting high-fidelity replication and repair while discriminating the error-prone repair mechanisms in eukaryotes.
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Affiliation(s)
- Xiaoli Gan
- Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, TaiKang Center for Life and Medical Sciences, Frontier Science Centre of Immunology and Metabolism, Wuhan University, Wuhan, Hubei 430072, China
| | - Yueyue Zhang
- The First Affiliated Hospital of USTC, MOE Key Laboratory for Membraneless Organelles and Cellular Dynamics, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, Anhui 230001, China
| | - Donghao Jiang
- Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, TaiKang Center for Life and Medical Sciences, Frontier Science Centre of Immunology and Metabolism, Wuhan University, Wuhan, Hubei 430072, China
| | - Jingyao Shi
- Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, TaiKang Center for Life and Medical Sciences, Frontier Science Centre of Immunology and Metabolism, Wuhan University, Wuhan, Hubei 430072, China
| | - Han Zhao
- Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, TaiKang Center for Life and Medical Sciences, Frontier Science Centre of Immunology and Metabolism, Wuhan University, Wuhan, Hubei 430072, China
| | - Chengyu Xie
- Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, TaiKang Center for Life and Medical Sciences, Frontier Science Centre of Immunology and Metabolism, Wuhan University, Wuhan, Hubei 430072, China
| | - Yanyan Wang
- Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, TaiKang Center for Life and Medical Sciences, Frontier Science Centre of Immunology and Metabolism, Wuhan University, Wuhan, Hubei 430072, China
| | - Jingyan Xu
- Department of Hematology, Nanjing Drum Tower Hospital, the Affiliated Hospital of Nanjing University Medical School, Nanjing, China
| | - Xinghua Zhang
- Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, TaiKang Center for Life and Medical Sciences, Frontier Science Centre of Immunology and Metabolism, Wuhan University, Wuhan, Hubei 430072, China
| | - Gang Cai
- The First Affiliated Hospital of USTC, MOE Key Laboratory for Membraneless Organelles and Cellular Dynamics, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, Anhui 230001, China
| | - Hailong Wang
- Beijing Key Laboratory of DNA Damage Response and College of Life Sciences, Capital Normal University, Beijing 100048, China
| | - Jun Huang
- The MOE Key Laboratory of Biosystems Homeostasis & Protection, Zhejiang Provincial Key Laboratory for Cancer Molecular Cell Biology and Innovation Center for Cell Signaling Network, Life Sciences Institute, Zhejiang University, Hangzhou 310058, China
| | - Xuefeng Chen
- Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, TaiKang Center for Life and Medical Sciences, Frontier Science Centre of Immunology and Metabolism, Wuhan University, Wuhan, Hubei 430072, China
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37
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Zeng J, Nguyen MA, Liu P, Ferreira da Silva L, Lin LY, Justus DG, Petri K, Clement K, Porter SN, Verma A, Neri NR, Rosanwo T, Ciuculescu MF, Abriss D, Mintzer E, Maitland SA, Demirci S, Tisdale JF, Williams DA, Zhu LJ, Pruett-Miller SM, Pinello L, Joung JK, Pattanayak V, Manis JP, Armant M, Pellin D, Brendel C, Wolfe SA, Bauer DE. Gene editing without ex vivo culture evades genotoxicity in human hematopoietic stem cells. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.05.27.542323. [PMID: 37292647 PMCID: PMC10245949 DOI: 10.1101/2023.05.27.542323] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Gene editing the BCL11A erythroid enhancer is a validated approach to fetal hemoglobin (HbF) induction for β-hemoglobinopathy therapy, though heterogeneity in edit allele distribution and HbF response may impact its safety and efficacy. Here we compared combined CRISPR-Cas9 endonuclease editing of the BCL11A +58 and +55 enhancers with leading gene modification approaches under clinical investigation. We found that combined targeting of the BCL11A +58 and +55 enhancers with 3xNLS-SpCas9 and two sgRNAs resulted in superior HbF induction, including in engrafting erythroid cells from sickle cell disease (SCD) patient xenografts, attributable to simultaneous disruption of core half E-box/GATA motifs at both enhancers. We corroborated prior observations that double strand breaks (DSBs) could produce unintended on- target outcomes in hematopoietic stem and progenitor cells (HSPCs) such as long deletions and centromere-distal chromosome fragment loss. We show these unintended outcomes are a byproduct of cellular proliferation stimulated by ex vivo culture. Editing HSPCs without cytokine culture bypassed long deletion and micronuclei formation while preserving efficient on-target editing and engraftment function. These results indicate that nuclease editing of quiescent hematopoietic stem cells (HSCs) limits DSB genotoxicity while maintaining therapeutic potency and encourages efforts for in vivo delivery of nucleases to HSCs.
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38
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Pai CC, Durley SC, Cheng WC, Chiang NY, Peters J, Kasparek T, Blaikley E, Wee BY, Walker C, Kearsey SE, Buffa F, Murray JM, Humphrey TC. Homologous recombination suppresses transgenerational DNA end resection and chromosomal instability in fission yeast. Nucleic Acids Res 2023; 51:3205-3222. [PMID: 36951111 PMCID: PMC10123110 DOI: 10.1093/nar/gkad160] [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: 10/01/2022] [Revised: 02/13/2023] [Accepted: 02/23/2023] [Indexed: 03/24/2023] Open
Abstract
Chromosomal instability (CIN) drives cell-to-cell heterogeneity, and the development of genetic diseases, including cancer. Impaired homologous recombination (HR) has been implicated as a major driver of CIN, however, the underlying mechanism remains unclear. Using a fission yeast model system, we establish a common role for HR genes in suppressing DNA double-strand break (DSB)-induced CIN. Further, we show that an unrepaired single-ended DSB arising from failed HR repair or telomere loss is a potent driver of widespread CIN. Inherited chromosomes carrying a single-ended DSB are subject to cycles of DNA replication and extensive end-processing across successive cell divisions. These cycles are enabled by Cullin 3-mediated Chk1 loss and checkpoint adaptation. Subsequent propagation of unstable chromosomes carrying a single-ended DSB continues until transgenerational end-resection leads to fold-back inversion of single-stranded centromeric repeats and to stable chromosomal rearrangements, typically isochromosomes, or to chromosomal loss. These findings reveal a mechanism by which HR genes suppress CIN and how DNA breaks that persist through mitotic divisions propagate cell-to-cell heterogeneity in the resultant progeny.
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Affiliation(s)
- Chen-Chun Pai
- MRC Oxford Institute for Radiation Oncology & Biology, Department of Oncology, University of Oxford, Old Road Campus Research Building, Roosevelt Drive, Oxford OX3 7DQ, UK
| | - Samuel C Durley
- MRC Oxford Institute for Radiation Oncology & Biology, Department of Oncology, University of Oxford, Old Road Campus Research Building, Roosevelt Drive, Oxford OX3 7DQ, UK
| | - Wei-Chen Cheng
- MRC Oxford Institute for Radiation Oncology & Biology, Department of Oncology, University of Oxford, Old Road Campus Research Building, Roosevelt Drive, Oxford OX3 7DQ, UK
| | - Nien-Yi Chiang
- MRC Oxford Institute for Radiation Oncology & Biology, Department of Oncology, University of Oxford, Old Road Campus Research Building, Roosevelt Drive, Oxford OX3 7DQ, UK
| | - Jennifer Peters
- MRC Oxford Institute for Radiation Oncology & Biology, Department of Oncology, University of Oxford, Old Road Campus Research Building, Roosevelt Drive, Oxford OX3 7DQ, UK
| | - Torben Kasparek
- MRC Oxford Institute for Radiation Oncology & Biology, Department of Oncology, University of Oxford, Old Road Campus Research Building, Roosevelt Drive, Oxford OX3 7DQ, UK
| | - Elizabeth Blaikley
- MRC Oxford Institute for Radiation Oncology & Biology, Department of Oncology, University of Oxford, Old Road Campus Research Building, Roosevelt Drive, Oxford OX3 7DQ, UK
| | - Boon-Yu Wee
- MRC Oxford Institute for Radiation Oncology & Biology, Department of Oncology, University of Oxford, Old Road Campus Research Building, Roosevelt Drive, Oxford OX3 7DQ, UK
| | - Carol Walker
- MRC Oxford Institute for Radiation Oncology & Biology, Department of Oncology, University of Oxford, Old Road Campus Research Building, Roosevelt Drive, Oxford OX3 7DQ, UK
| | - Stephen E Kearsey
- Department of Biology, University of Oxford, Zoology Research and Administration Building, Mansfield Road, Oxford OX1 3SZ, UK
| | - Francesca Buffa
- MRC Oxford Institute for Radiation Oncology & Biology, Department of Oncology, University of Oxford, Old Road Campus Research Building, Roosevelt Drive, Oxford OX3 7DQ, UK
| | - Johanne M Murray
- Genome Damage and Stability Centre, School of Life Sciences, University of Sussex, Falmer, Brighton, SussexBN1 9RQ, UK
| | - Timothy C Humphrey
- MRC Oxford Institute for Radiation Oncology & Biology, Department of Oncology, University of Oxford, Old Road Campus Research Building, Roosevelt Drive, Oxford OX3 7DQ, UK
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39
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Binet R, Lambert JP, Tomkova M, Tischfield S, Baggiolini A, Picaud S, Sarkar S, Louphrasitthiphol P, Dias D, Carreira S, Humphrey T, Fillipakopoulos P, White R, Goding CR. DNA damage-induced interaction between a lineage addiction oncogenic transcription factor and the MRN complex shapes a tissue-specific DNA Damage Response and cancer predisposition. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.04.21.537819. [PMID: 37131595 PMCID: PMC10153263 DOI: 10.1101/2023.04.21.537819] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Since genome instability can drive cancer initiation and progression, cells have evolved highly effective and ubiquitous DNA Damage Response (DDR) programs. However, some cells, in skin for example, are normally exposed to high levels of DNA damaging agents. Whether such high-risk cells possess lineage-specific mechanisms that tailor DNA repair to the tissue remains largely unknown. Here we show, using melanoma as a model, that the microphthalmia-associated transcription factor MITF, a lineage addition oncogene that coordinates many aspects of melanocyte and melanoma biology, plays a non-transcriptional role in shaping the DDR. On exposure to DNA damaging agents, MITF is phosphorylated by ATM/DNA-PKcs, and unexpectedly its interactome is dramatically remodelled; most transcription (co)factors dissociate, and instead MITF interacts with the MRE11-RAD50-NBS1 (MRN) complex. Consequently, cells with high MITF levels accumulate stalled replication forks, and display defects in homologous recombination-mediated repair associated with impaired MRN recruitment to DNA damage. In agreement, high MITF levels are associated with increased SNV burden in melanoma. Significantly, the SUMOylation-defective MITF-E318K melanoma predisposition mutation recapitulates the effects of ATM/DNA-PKcs-phosphorylated MITF. Our data suggest that a non-transcriptional function of a lineage-restricted transcription factor contributes to a tissue-specialised modulation of the DDR that can impact cancer initiation.
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Affiliation(s)
- Romuald Binet
- Ludwig Institute for Cancer Research, Nuffield Department of Clinical Medicine, University of Oxford, Headington, Oxford, OX3 7DQ, UK
| | - Jean-Philippe Lambert
- Department of Molecular Medicine, Cancer Research Center and Big Data Research Center, Université Laval, Quebec, Canada; Endocrinology – Nephrology Axis, CHU de Québec – Université Laval Research Center, Quebec City, QC, Canada, G1V 4G2
| | - Marketa Tomkova
- Ludwig Institute for Cancer Research, Nuffield Department of Clinical Medicine, University of Oxford, Headington, Oxford, OX3 7DQ, UK
- Department of Biochemistry and Molecular Medicine, University of California, Davis, USA
| | - Samuel Tischfield
- Department of Epidemiology and Biostatistics, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
- Human Oncology and Pathogenesis Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
- Marie-Josée and Henry R. Kravis Center for Molecular Oncology, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
| | - Arianna Baggiolini
- Center for Stem Cell Biology and Developmental Biology Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
| | - Sarah Picaud
- Structural Genomics Consortium, Nuffield Department of Clinical Medicine, University of Oxford, Oxford OX3 7DQ, UK
| | - Sovan Sarkar
- CRUK MRC Oxford Institute for Radiation Oncology, Department of Oncology, University of Oxford, Oxford OX3 7DQ, UK
| | - Pakavarin Louphrasitthiphol
- Ludwig Institute for Cancer Research, Nuffield Department of Clinical Medicine, University of Oxford, Headington, Oxford, OX3 7DQ, UK
| | - Diogo Dias
- Ludwig Institute for Cancer Research, Nuffield Department of Clinical Medicine, University of Oxford, Headington, Oxford, OX3 7DQ, UK
| | - Suzanne Carreira
- Ludwig Institute for Cancer Research, Nuffield Department of Clinical Medicine, University of Oxford, Headington, Oxford, OX3 7DQ, UK
| | - Timothy Humphrey
- CRUK MRC Oxford Institute for Radiation Oncology, Department of Oncology, University of Oxford, Oxford OX3 7DQ, UK
| | - Panagis Fillipakopoulos
- Ludwig Institute for Cancer Research, Nuffield Department of Clinical Medicine, University of Oxford, Headington, Oxford, OX3 7DQ, UK
- Structural Genomics Consortium, Nuffield Department of Clinical Medicine, University of Oxford, Oxford OX3 7DQ, UK
| | - Richard White
- Ludwig Institute for Cancer Research, Nuffield Department of Clinical Medicine, University of Oxford, Headington, Oxford, OX3 7DQ, UK
- Department of Cancer Biology and Genetics, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
| | - Colin R Goding
- Ludwig Institute for Cancer Research, Nuffield Department of Clinical Medicine, University of Oxford, Headington, Oxford, OX3 7DQ, UK
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40
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Arcangioli B, Gangloff S. The Fission Yeast Mating-Type Switching Motto: "One-for-Two" and "Two-for-One". Microbiol Mol Biol Rev 2023; 87:e0000821. [PMID: 36629411 PMCID: PMC10029342 DOI: 10.1128/mmbr.00008-21] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Schizosaccharomyces pombe is an ascomycete fungus that divides by medial fission; it is thus commonly referred to as fission yeast, as opposed to the distantly related budding yeast Saccharomyces cerevisiae. The reproductive lifestyle of S. pombe relies on an efficient genetic sex determination system generating a 1:1 sex ratio and using alternating haploid/diploid phases in response to environmental conditions. In this review, we address how one haploid cell manages to generate two sister cells with opposite mating types, a prerequisite to conjugation and meiosis. This mating-type switching process depends on two highly efficient consecutive asymmetric cell divisions that rely on DNA replication, repair, and recombination as well as the structure and components of heterochromatin. We pay special attention to the intimate interplay between the genetic and epigenetic partners involved in this process to underscore the importance of basic research and its profound implication for a better understanding of chromatin biology.
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Affiliation(s)
- Benoît Arcangioli
- Genome Dynamics Unit, Genomes and Genetics Department, Pasteur Institute, Paris, France
| | - Serge Gangloff
- Genome Dynamics Unit, Genomes and Genetics Department, Pasteur Institute, Paris, France
- UMR3525, Genetics of Genomes, CNRS-Pasteur Institute, Paris, France
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41
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He L, Lever R, Cubbon A, Tehseen M, Jenkins T, Nottingham AO, Horton A, Betts H, Fisher M, Hamdan SM, Soultanas P, Bolt EL. Interaction of human HelQ with DNA polymerase delta halts DNA synthesis and stimulates DNA single-strand annealing. Nucleic Acids Res 2023; 51:1740-1749. [PMID: 36718939 PMCID: PMC9976902 DOI: 10.1093/nar/gkad032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2022] [Revised: 01/05/2023] [Accepted: 01/10/2023] [Indexed: 02/01/2023] Open
Abstract
DNA strand breaks are repaired by DNA synthesis from an exposed DNA end paired with a homologous DNA template. DNA polymerase delta (Pol δ) catalyses DNA synthesis in multiple eukaryotic DNA break repair pathways but triggers genome instability unless its activity is restrained. We show that human HelQ halts DNA synthesis by isolated Pol δ and Pol δ-PCNA-RPA holoenzyme. Using novel HelQ mutant proteins we identify that inhibition of Pol δ is independent of DNA binding, and maps to a 70 amino acid intrinsically disordered region of HelQ. Pol δ and its POLD3 subunit robustly stimulated DNA single-strand annealing by HelQ, and POLD3 and HelQ interact physically via the intrinsically disordered HelQ region. This data, and inability of HelQ to inhibit DNA synthesis by the POLD1 catalytic subunit of Pol δ, reveal a mechanism for limiting DNA synthesis and promoting DNA strand annealing during human DNA break repair, which centres on POLD3.
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Affiliation(s)
- Liu He
- School of Life Sciences, University of Nottingham, Nottingham, UK
| | - Rebecca Lever
- School of Life Sciences, University of Nottingham, Nottingham, UK
| | - Andrew Cubbon
- School of Life Sciences, University of Nottingham, Nottingham, UK
| | - Muhammad Tehseen
- Bioscience Program, Biological and Environmental Science and Engineering, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
| | - Tabitha Jenkins
- School of Life Sciences, University of Nottingham, Nottingham, UK
| | | | - Anya Horton
- School of Life Sciences, University of Nottingham, Nottingham, UK
| | - Hannah Betts
- Biodiscovery Institute, School of Chemistry, University of Nottingham, Nottingham, UK
| | | | - Samir M Hamdan
- Bioscience Program, Biological and Environmental Science and Engineering, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
| | - Panos Soultanas
- Biodiscovery Institute, School of Chemistry, University of Nottingham, Nottingham, UK
| | - Edward L Bolt
- School of Life Sciences, University of Nottingham, Nottingham, UK
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Rider SD, Damewood FJ, Gadgil RY, Hitch DC, Alhawach V, Shrestha R, Shanahan M, Zavada N, Leffak M. Suppressors of Break-Induced Replication in Human Cells. Genes (Basel) 2023; 14:genes14020398. [PMID: 36833325 PMCID: PMC9956954 DOI: 10.3390/genes14020398] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2022] [Revised: 01/23/2023] [Accepted: 01/29/2023] [Indexed: 02/05/2023] Open
Abstract
Short tandem DNA repeats are drivers of genome instability. To identify suppressors of break-induced mutagenesis human cells, unbiased genetic screens were conducted using a lentiviral shRNA library. The recipient cells possessed fragile non-B DNA that could induce DNA double-strand breaks (DSBs), integrated at an ectopic chromosomal site adjacent to a thymidine kinase marker gene. Mutagenesis of the thymidine kinase gene rendered cells resistant to the nucleoside analog ganciclovir (GCV). The screen identified genes that have established roles in DNA replication and repair, chromatin modification, responses to ionizing radiation, and genes encoding proteins enriched at replication forks. Novel loci implicated in BIR included olfactory receptors, the G0S2 oncogene/tumor suppressor axis, the EIF3H-METTL3 translational regulator, and the SUDS3 subunit of the Sin3A corepressor. Consistent with a role in suppressing BIR, siRNA knockdown of selected candidates increased the frequency of the GCVr phenotype and increased DNA rearrangements near the ectopic non-B DNA. Inverse PCR and DNA sequence analyses showed that hits identified in the screen increased genome instability. Further analysis quantitated repeat-induced hypermutagenesis at the ectopic site and showed that knockdown of a primary hit, COPS2, induced mutagenic hotspots, remodeled the replication fork, and increased nonallelic chromosome template switches.
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Barnes RP, Thosar SA, Opresko PL. Telomere Fragility and MiDAS: Managing the Gaps at the End of the Road. Genes (Basel) 2023; 14:genes14020348. [PMID: 36833275 PMCID: PMC9956152 DOI: 10.3390/genes14020348] [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: 12/28/2022] [Revised: 01/20/2023] [Accepted: 01/24/2023] [Indexed: 01/31/2023] Open
Abstract
Telomeres present inherent difficulties to the DNA replication machinery due to their repetitive sequence content, formation of non-B DNA secondary structures, and the presence of the nucleo-protein t-loop. Especially in cancer cells, telomeres are hot spots for replication stress, which can result in a visible phenotype in metaphase cells termed "telomere fragility". A mechanism cells employ to mitigate replication stress, including at telomeres, is DNA synthesis in mitosis (MiDAS). While these phenomena are both observed in mitotic cells, the relationship between them is poorly understood; however, a common link is DNA replication stress. In this review, we will summarize what is known to regulate telomere fragility and telomere MiDAS, paying special attention to the proteins which play a role in these telomere phenotypes.
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Affiliation(s)
- Ryan P. Barnes
- Department of Environmental and Occupational Health, School of Public Health, University of Pittsburgh, Pittsburgh, PA 15261, USA
- UPMC Hillman Cancer Center, University of Pittsburgh, 5117 Centre Avenue, Pittsburgh, PA 15213, USA
- Correspondence: (R.P.B.); (P.L.O.)
| | - Sanjana A. Thosar
- Department of Environmental and Occupational Health, School of Public Health, University of Pittsburgh, Pittsburgh, PA 15261, USA
- UPMC Hillman Cancer Center, University of Pittsburgh, 5117 Centre Avenue, Pittsburgh, PA 15213, USA
| | - Patricia L. Opresko
- Department of Environmental and Occupational Health, School of Public Health, University of Pittsburgh, Pittsburgh, PA 15261, USA
- UPMC Hillman Cancer Center, University of Pittsburgh, 5117 Centre Avenue, Pittsburgh, PA 15213, USA
- Department of Pharmacology and Chemical Biology, School of Medicine, University of Pittsburgh, Pittsburgh, PA 15213, USA
- Correspondence: (R.P.B.); (P.L.O.)
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Black JA, Reis-Cunha JL, Cruz AK, Tosi LR. Life in plastic, it's fantastic! How Leishmania exploit genome instability to shape gene expression. Front Cell Infect Microbiol 2023; 13:1102462. [PMID: 36779182 PMCID: PMC9910336 DOI: 10.3389/fcimb.2023.1102462] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Accepted: 01/05/2023] [Indexed: 01/27/2023] Open
Abstract
Leishmania are kinetoplastid pathogens that cause leishmaniasis, a debilitating and potentially life-threatening infection if untreated. Unusually, Leishmania regulate their gene expression largely post-transcriptionally due to the arrangement of their coding genes into polycistronic transcription units that may contain 100s of functionally unrelated genes. Yet, Leishmania are capable of rapid and responsive changes in gene expression to challenging environments, often instead correlating with dynamic changes in their genome composition, ranging from chromosome and gene copy number variations to the generation of extrachromosomal DNA and the accumulation of point mutations. Typically, such events indicate genome instability in other eukaryotes, coinciding with genetic abnormalities, but for Leishmania, exploiting these products of genome instability can provide selectable substrates to catalyse necessary gene expression changes by modifying gene copy number. Unorthodox DNA replication, DNA repair, replication stress factors and DNA repeats are recognised in Leishmania as contributors to this intrinsic instability, but how Leishmania regulate genome plasticity to enhance fitness whilst limiting toxic under- or over-expression of co-amplified and co-transcribed genes is unclear. Herein, we focus on fresh, and detailed insights that improve our understanding of genome plasticity in Leishmania. Furthermore, we discuss emerging models and factors that potentially circumvent regulatory issues arising from polycistronic transcription. Lastly, we highlight key gaps in our understanding of Leishmania genome plasticity and discuss future studies to define, in higher resolution, these complex regulatory interactions.
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Affiliation(s)
- Jennifer A. Black
- Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, Brazil,The Wellcome Centre for Integrative Parasitology, School of Infection, Immunity, and Inflammation, University of Glasgow, Glasgow, United Kingdom,*Correspondence: Luiz. R.O. Tosi, ; Jennifer A. Black,
| | | | - Angela. K. Cruz
- Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, Brazil
| | - Luiz. R.O. Tosi
- Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, Brazil,*Correspondence: Luiz. R.O. Tosi, ; Jennifer A. Black,
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Gospodinov A, Dzhokova S, Petrova M, Ugrinova I. Chromatin regulators in DNA replication and genome stability maintenance during S-phase. ADVANCES IN PROTEIN CHEMISTRY AND STRUCTURAL BIOLOGY 2023; 135:243-280. [PMID: 37061334 DOI: 10.1016/bs.apcsb.2023.02.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/30/2023]
Abstract
The duplication of genetic information is central to life. The replication of genetic information is strictly controlled to ensure that each piece of genomic DNA is copied only once during a cell cycle. Factors that slow or stop replication forks cause replication stress. Replication stress is a major source of genome instability in cancer cells. Multiple control mechanisms facilitate the unimpeded fork progression, prevent fork collapse and coordinate fork repair. Chromatin alterations, caused by histone post-translational modifications and chromatin remodeling, have critical roles in normal replication and in avoiding replication stress and its consequences. This text reviews the chromatin regulators that ensure DNA replication and the proper response to replication stress. We also briefly touch on exploiting replication stress in therapeutic strategies. As chromatin regulators are frequently mutated in cancer, manipulating their activity could provide many possibilities for personalized treatment.
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Affiliation(s)
- Anastas Gospodinov
- Roumen Tsanev Institute of Molecular Biology, Bulgarian Academy of Sciences, Sofia, Bulgaria.
| | - Stefka Dzhokova
- Roumen Tsanev Institute of Molecular Biology, Bulgarian Academy of Sciences, Sofia, Bulgaria
| | - Maria Petrova
- Roumen Tsanev Institute of Molecular Biology, Bulgarian Academy of Sciences, Sofia, Bulgaria
| | - Iva Ugrinova
- Roumen Tsanev Institute of Molecular Biology, Bulgarian Academy of Sciences, Sofia, Bulgaria
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CRISPR-Cas9 Editing Induces Loss of Heterozygosity in the Pathogenic Yeast Candida parapsilosis. mSphere 2022; 7:e0039322. [PMID: 36416551 PMCID: PMC9769790 DOI: 10.1128/msphere.00393-22] [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] [Indexed: 11/24/2022] Open
Abstract
Genetic manipulation is often used to study gene function. However, unplanned genome changes (including single nucleotide polymorphisms [SNPs], aneuploidy, and loss of heterozygosity [LOH]) can affect the phenotypic traits of the engineered strains. Here, we compared the effect of classical deletion methods (replacing target alleles with selectable markers by homologous recombination) with CRISPR-Cas9 editing in the diploid human-pathogenic yeast Candida parapsilosis. We sequenced the genomes of 9 isolates that were modified using classic recombination methods and 12 that were edited using CRISPR-Cas9. As a control, the genomes of eight isolates that were transformed with a Cas9-expressing plasmid in the absence of a guide RNA were also sequenced. Following gene manipulation using classic homologous recombination, only one strain exhibited extensive LOH near the targeted gene (8.9 kb), whereas another contained multiple LOH events not associated with the intended modification. In contrast, large regions of LOH (up to >1,100 kb) were observed in most CRISPR-Cas9-edited strains. LOH most commonly occurred adjacent to the Cas9 cut site and extended to the telomere in four isolates. In two isolates, we observed LOH on chromosomes that were not targeted by CRISPR-Cas9. Among the CRISPR-edited isolates, two exhibited cysteine and methionine auxotrophy caused by LOH at a heterozygous site in MET10, approximately 11 and 157 kb downstream from the Cas9 target site, respectively. C. parapsilosis isolates have relatively low levels of heterozygosity. However, our results show that mutation complementation to confirm observed phenotypes is required when using CRISPR-Cas9. IMPORTANCE CRISPR-Cas9 has greatly streamlined gene editing and is now the gold standard and first choice for genetic engineering. However, we show that in diploid species, extra care should be taken in confirming the cause of any phenotypic changes observed. We show that the Cas9-induced double-strand break is often associated with loss of heterozygosity in the asexual diploid human fungal pathogen Candida parapsilosis. This can result in deleterious heterozygous variants (e.g., stop gain in one allele) becoming homozygous, resulting in unplanned phenotypic changes. Our results stress the importance of mutation complementation even when using CRISPR-Cas9.
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47
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Bhat DS, Spies MA, Spies M. A moving target for drug discovery: Structure activity relationship and many genome (de)stabilizing functions of the RAD52 protein. DNA Repair (Amst) 2022; 120:103421. [PMID: 36327799 PMCID: PMC9888176 DOI: 10.1016/j.dnarep.2022.103421] [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: 07/29/2022] [Revised: 10/18/2022] [Accepted: 10/24/2022] [Indexed: 02/02/2023]
Abstract
BRCA-ness phenotype, a signature of many breast and ovarian cancers, manifests as deficiency in homologous recombination, and as defects in protection and repair of damaged DNA replication forks. A dependence of such cancers on DNA repair factors less important for survival of BRCA-proficient cells, offers opportunities for development of novel chemotherapeutic interventions. The first drugs targeting BRCA-deficient cancers, poly-ADP-ribose polymerase (PARP) inhibitors have been approved for the treatment of advanced, chemotherapy resistant cancers in patients with BRCA1/2 germline mutations. Nine additional proteins that can be targeted to selectively kill BRCA-deficient cancer cells have been identified. Among them, a DNA repair protein RAD52 is an especially attractive target due to general tolerance of the RAD52 loss of function, and protective role of an inactivating mutation. Yet, the effective pharmacological inhibitors of RAD52 have not been forthcoming. In this review, we discuss advances in the state of our knowledge of the RAD52 structure, activities and cellular functions, with a specific focus on the features that make RAD52 an attractive, but difficult drug target.
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Affiliation(s)
- Divya S Bhat
- Department of Biochemistry, University of Iowa Carver College of Medicine, 51 Newton Road, Iowa City, IA 52242, USA
| | - M Ashley Spies
- Department of Biochemistry, University of Iowa Carver College of Medicine, 51 Newton Road, Iowa City, IA 52242, USA; Division of Medicinal and Natural Products Chemistry, Department of Pharmaceutical Sciences and Experimental Therapeutics, The University of Iowa, Iowa City, Iowa 52242, USA
| | - Maria Spies
- Department of Biochemistry, University of Iowa Carver College of Medicine, 51 Newton Road, Iowa City, IA 52242, USA.
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48
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Morgunova VV, Sokolova OA, Sizova TV, Malaev LG, Babaev DS, Kwon DA, Kalmykova AI. Dysfunction of Lamin B and Physiological Aging Cause Telomere Instability in Drosophila Germline. BIOCHEMISTRY. BIOKHIMIIA 2022; 87:1600-1610. [PMID: 36717449 DOI: 10.1134/s000629792212015x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Chromatin spatial organization in the nucleus is essential for the genome functioning and regulation of gene activity. The nuclear lamina and lamina-associated proteins, lamins, play a key role in this process. Lamin dysfunction leads to the decompaction and transcriptional activation of heterochromatin, which is associated with the premature aging syndrome. In many cell types, telomeres are located at the nuclear periphery, where their replication and stability are ensured by the nuclear lamina. Moreover, diseases associated with defects in lamins and telomeres have similar manifestations and resemble physiological aging. Understanding molecular changes associated with aging at the organismal level is especially important. In this study, we compared the effects caused by the mutation in lamin B and physiological aging in the germline of the model organism Drosophila melanogaster. We have shown that the impaired localization of lamin B leads to the heterochromatin decompaction and transcriptional activation of some transposable elements and telomeric repeats. Both DNA damage and activation of homologous recombination in the telomeres were observed in the germ cells of lamin B mutants. The instability of repeat-enriched heterochromatin can be directly related to the genome destabilization, germ cell death, and sterility observed in lamin B mutants. Similar processes were observed in Drosophila germline in the course of physiological aging, which indicates a close link between the maintenance of the heterochromatin stability at the nuclear periphery and mechanisms of aging.
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Affiliation(s)
- Valeriya V Morgunova
- Institute of Molecular Genetics of National Research Centre "Kurchatov Institute", Moscow, 123182, Russia
| | - Olesya A Sokolova
- Institute of Molecular Genetics of National Research Centre "Kurchatov Institute", Moscow, 123182, Russia
| | - Tatyana V Sizova
- Institute of Molecular Genetics of National Research Centre "Kurchatov Institute", Moscow, 123182, Russia
| | - Leonid G Malaev
- Institute of Molecular Genetics of National Research Centre "Kurchatov Institute", Moscow, 123182, Russia.,Faculty of Biotechnology, Lomonosov Moscow State University, Moscow, 119991, Russia
| | - Dmitry S Babaev
- Institute of Molecular Genetics of National Research Centre "Kurchatov Institute", Moscow, 123182, Russia.,Faculty of Biotechnology, Lomonosov Moscow State University, Moscow, 119991, Russia
| | - Dmitry A Kwon
- Kurchatov Center for Genome Research, National Research Centre "Kurchatov Institute", Moscow, 123182, Russia
| | - Alla I Kalmykova
- Institute of Molecular Genetics of National Research Centre "Kurchatov Institute", Moscow, 123182, Russia.
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49
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Reusswig KU, Bittmann J, Peritore M, Courtes M, Pardo B, Wierer M, Mann M, Pfander B. Unscheduled DNA replication in G1 causes genome instability and damage signatures indicative of replication collisions. Nat Commun 2022; 13:7014. [PMID: 36400763 PMCID: PMC9674678 DOI: 10.1038/s41467-022-34379-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2021] [Accepted: 10/24/2022] [Indexed: 11/19/2022] Open
Abstract
DNA replicates once per cell cycle. Interfering with the regulation of DNA replication initiation generates genome instability through over-replication and has been linked to early stages of cancer development. Here, we engineer genetic systems in budding yeast to induce unscheduled replication in a G1-like cell cycle state. Unscheduled G1 replication initiates at canonical S-phase origins. We quantifiy the composition of replisomes in G1- and S-phase and identified firing factors, polymerase α, and histone supply as factors that limit replication outside S-phase. G1 replication per se does not trigger cellular checkpoints. Subsequent replication during S-phase, however, results in over-replication and leads to chromosome breaks and chromosome-wide, strand-biased occurrence of RPA-bound single-stranded DNA, indicating head-to-tail replication collisions as a key mechanism generating genome instability upon G1 replication. Low-level, sporadic induction of G1 replication induces an identical response, indicating findings from synthetic systems are applicable to naturally occurring scenarios of unscheduled replication initiation.
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Affiliation(s)
- Karl-Uwe Reusswig
- grid.418615.f0000 0004 0491 845XDNA Replication and Genome Integrity, Max Planck Institute of Biochemistry, 82152 Martinsried, Germany ,grid.38142.3c000000041936754XPresent Address: Department of Cell Biology, Blavatnik Institute, Harvard Medical School, Boston, MA 02115 USA ,grid.65499.370000 0001 2106 9910Present Address: Department of Pediatric Oncology, Dana-Farber Cancer Institute, Boston, MA 02215 USA
| | - Julia Bittmann
- grid.418615.f0000 0004 0491 845XDNA Replication and Genome Integrity, Max Planck Institute of Biochemistry, 82152 Martinsried, Germany
| | - Martina Peritore
- grid.418615.f0000 0004 0491 845XDNA Replication and Genome Integrity, Max Planck Institute of Biochemistry, 82152 Martinsried, Germany ,grid.7551.60000 0000 8983 7915Present Address: Genome Maintenance Mechanisms in Health and Disease, Institute of Aerospace Medicine, German Aerospace Center (DLR), 51147 Cologne, Germany
| | - Mathilde Courtes
- grid.433120.7Institut de Génétique Humaine (IGH), Université de Montpellier – Centre National de la Recherche Scientifique, 34396 Montpellier, France
| | - Benjamin Pardo
- grid.433120.7Institut de Génétique Humaine (IGH), Université de Montpellier – Centre National de la Recherche Scientifique, 34396 Montpellier, France
| | - Michael Wierer
- grid.418615.f0000 0004 0491 845XProteomics and Signal Transduction, Max Planck Institute of Biochemistry, 82152 Martinsried, Germany ,grid.5254.60000 0001 0674 042XPresent Address: Proteomics Research Infrastructure, University of Copenhagen, 2200 Copenhagen, Denmark
| | - Matthias Mann
- grid.418615.f0000 0004 0491 845XProteomics and Signal Transduction, Max Planck Institute of Biochemistry, 82152 Martinsried, Germany
| | - Boris Pfander
- grid.418615.f0000 0004 0491 845XDNA Replication and Genome Integrity, Max Planck Institute of Biochemistry, 82152 Martinsried, Germany ,grid.7551.60000 0000 8983 7915Present Address: Genome Maintenance Mechanisms in Health and Disease, Institute of Aerospace Medicine, German Aerospace Center (DLR), 51147 Cologne, Germany ,grid.6190.e0000 0000 8580 3777Present Address: Genome Maintenance Mechanisms in Health and Disease, Institute of Genome Stability in Ageing and Disease, CECAD Research Center, University of Cologne, 50931 Cologne, Germany
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50
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Sister chromatid exchanges induced by perturbed replication can form independently of BRCA1, BRCA2 and RAD51. Nat Commun 2022; 13:6722. [PMID: 36344511 PMCID: PMC9640580 DOI: 10.1038/s41467-022-34519-8] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2021] [Accepted: 10/27/2022] [Indexed: 11/09/2022] Open
Abstract
Sister chromatid exchanges (SCEs) are products of joint DNA molecule resolution, and are considered to form through homologous recombination (HR). Indeed, SCE induction upon irradiation requires the canonical HR factors BRCA1, BRCA2 and RAD51. In contrast, replication-blocking agents, including PARP inhibitors, induce SCEs independently of BRCA1, BRCA2 and RAD51. PARP inhibitor-induced SCEs are enriched at difficult-to-replicate genomic regions, including common fragile sites (CFSs). PARP inhibitor-induced replication lesions are transmitted into mitosis, suggesting that SCEs can originate from mitotic processing of under-replicated DNA. Proteomics analysis reveals mitotic recruitment of DNA polymerase theta (POLQ) to synthetic DNA ends. POLQ inactivation results in reduced SCE numbers and severe chromosome fragmentation upon PARP inhibition in HR-deficient cells. Accordingly, analysis of CFSs in cancer genomes reveals frequent allelic deletions, flanked by signatures of POLQ-mediated repair. Combined, we show PARP inhibition generates under-replicated DNA, which is processed into SCEs during mitosis, independently of canonical HR factors.
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