1
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Gera K, Cline C, Al-Mansour Z, Medvec A, Lee JH, Galochkina Z, Hsu J, Hiemenz J, Farhadfar N, Dean EA, Wingard JR, Brown R. A phase ib clinical trial of oral ciprofloxacin and etoposide in subjects with resistant acute myeloid leukemia. Leuk Lymphoma 2024:1-9. [PMID: 38841781 DOI: 10.1080/10428194.2024.2361111] [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: 01/22/2024] [Accepted: 05/23/2024] [Indexed: 06/07/2024]
Abstract
A phase 1b study was conducted to evaluate the safety and feasibility of ciprofloxacin and etoposide combination treatment in subjects with relapsed and refractory acute myeloid leukemia. Eleven subjects were enrolled in the study. Utilizing the standard '3 + 3' design, escalating ciprofloxacin doses (750 mg, 1000 mg) twice daily on D1-D10 in combination with a fixed dose (200 mg) of etoposide on D2-D8 were administered. Maximum tolerated dose was determined to be 1000 mg of ciprofloxacin in combination with 200 mg of etoposide. Serious adverse events occurred in 54.5% (n = 6) subjects and 91% (n = 10) subjects reported ≥ grade 3 toxicities. Nine subjects completed treatment, one had a dose-limiting toxicity, and one withdrew. One subject achieved complete remission with a duration of 111 days and one subject achieved morphologic leukemia-free state after cycle 1. While the combination demonstrated safety and an acceptable toxicity profile, only modest hematologic and clinical benefits were observed. This trial was registered at www.clinicaltrials.gov as #NCT02773732.
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Affiliation(s)
- Kriti Gera
- Department of Medicine, University of Florida College of Medicine, Gainesville, FL, USA
| | - Christina Cline
- Division of Hematology and Oncology, Department of Medicine, University of Florida College of Medicine, Gainesville, FL, USA
- University of Florida Health Cancer Center, Gainesville, FL, USA
| | - Zeina Al-Mansour
- Division of Hematology and Oncology, Department of Medicine, University of Florida College of Medicine, Gainesville, FL, USA
| | - Andrew Medvec
- Division of Hematology and Oncology, Department of Medicine, University of Florida College of Medicine, Gainesville, FL, USA
| | - Ji-Hyun Lee
- Department of Biostatistics, University of Florida Health Cancer Center, Gainesville, FL, USA
| | - Zhanna Galochkina
- Division of Quantitative Sciences, University of Florida Health Cancer Center, Gainesville, FL, USA
| | - Jack Hsu
- Division of Hematology and Oncology, Department of Medicine, University of Florida College of Medicine, Gainesville, FL, USA
| | - John Hiemenz
- Division of Hematology and Oncology, Department of Medicine, University of Florida College of Medicine, Gainesville, FL, USA
| | - Nosha Farhadfar
- Division of Hematology and Oncology, Department of Medicine, University of Florida College of Medicine, Gainesville, FL, USA
| | - Erin A Dean
- Division of Hematology and Oncology, Department of Medicine, University of Florida College of Medicine, Gainesville, FL, USA
| | - John R Wingard
- Division of Hematology and Oncology, Department of Medicine, University of Florida College of Medicine, Gainesville, FL, USA
- University of Florida Health Cancer Center, Gainesville, FL, USA
| | - Randy Brown
- Division of Hematology and Oncology, Department of Medicine, University of Florida College of Medicine, Gainesville, FL, USA
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2
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Blumenstiel JP. From the cauldron of conflict: Endogenous gene regulation by piRNA and other modes of adaptation enabled by selfish transposable elements. Semin Cell Dev Biol 2024; 164:1-12. [PMID: 38823219 DOI: 10.1016/j.semcdb.2024.05.001] [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: 10/10/2023] [Revised: 04/28/2024] [Accepted: 05/06/2024] [Indexed: 06/03/2024]
Abstract
Transposable elements (TEs) provide a prime example of genetic conflict because they can proliferate in genomes and populations even if they harm the host. However, numerous studies have shown that TEs, though typically harmful, can also provide fuel for adaptation. This is because they code functional sequences that can be useful for the host in which they reside. In this review, I summarize the "how" and "why" of adaptation enabled by the genetic conflict between TEs and hosts. In addition, focusing on mechanisms of TE control by small piwi-interacting RNAs (piRNAs), I highlight an indirect form of adaptation enabled by conflict. In this case, mechanisms of host defense that regulate TEs have been redeployed for endogenous gene regulation. I propose that the genetic conflict released by meiosis in early eukaryotes may have been important because, among other reasons, it spurred evolutionary innovation on multiple interwoven trajectories - on the part of hosts and also embedded genetic parasites. This form of evolution may function as a complexity generating engine that was a critical player in eukaryotic evolution.
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Affiliation(s)
- Justin P Blumenstiel
- Department of Ecology and Evolutionary Biology, University of Kansas, 1200 Sunnyside Avenue, Lawrence, KS 66045, United States.
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3
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Sasani TA, Quinlan AR, Harris K. Epistasis between mutator alleles contributes to germline mutation spectrum variability in laboratory mice. eLife 2024; 12:RP89096. [PMID: 38381482 PMCID: PMC10942616 DOI: 10.7554/elife.89096] [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] [Indexed: 02/22/2024] Open
Abstract
Maintaining germline genome integrity is essential and enormously complex. Although many proteins are involved in DNA replication, proofreading, and repair, mutator alleles have largely eluded detection in mammals. DNA replication and repair proteins often recognize sequence motifs or excise lesions at specific nucleotides. Thus, we might expect that the spectrum of de novo mutations - the frequencies of C>T, A>G, etc. - will differ between genomes that harbor either a mutator or wild-type allele. Previously, we used quantitative trait locus mapping to discover candidate mutator alleles in the DNA repair gene Mutyh that increased the C>A germline mutation rate in a family of inbred mice known as the BXDs (Sasani et al., 2022, Ashbrook et al., 2021). In this study we developed a new method to detect alleles associated with mutation spectrum variation and applied it to mutation data from the BXDs. We discovered an additional C>A mutator locus on chromosome 6 that overlaps Ogg1, a DNA glycosylase involved in the same base-excision repair network as Mutyh (David et al., 2007). Its effect depends on the presence of a mutator allele near Mutyh, and BXDs with mutator alleles at both loci have greater numbers of C>A mutations than those with mutator alleles at either locus alone. Our new methods for analyzing mutation spectra reveal evidence of epistasis between germline mutator alleles and may be applicable to mutation data from humans and other model organisms.
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Affiliation(s)
- Thomas A Sasani
- Department of Human Genetics, University of UtahSalt Lake CityUnited States
| | - Aaron R Quinlan
- Department of Human Genetics, University of UtahSalt Lake CityUnited States
- Department of Biomedical Informatics, University of UtahSalt Lake CityUnited States
| | - Kelley Harris
- Department of Genome Sciences, University of WashingtonSeattleUnited States
- Herbold Computational Biology Program, Fred Hutch Cancer CenterSeattleUnited States
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4
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Sasani TA, Quinlan AR, Harris K. Epistasis between mutator alleles contributes to germline mutation spectra variability in laboratory mice. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.04.25.537217. [PMID: 37162999 PMCID: PMC10168256 DOI: 10.1101/2023.04.25.537217] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Maintaining germline genome integrity is essential and enormously complex. Although many proteins are involved in DNA replication, proofreading, and repair [1], mutator alleles have largely eluded detection in mammals. DNA replication and repair proteins often recognize sequence motifs or excise lesions at specific nucleotides. Thus, we might expect that the spectrum of de novo mutations - the frequencies of C>T, A>G, etc. - will differ between genomes that harbor either a mutator or wild-type allele. Previously, we used quantitative trait locus mapping to discover candidate mutator alleles in the DNA repair gene Mutyh that increased the C>A germline mutation rate in a family of inbred mice known as the BXDs [2,3]. In this study we developed a new method to detect alleles associated with mutation spectrum variation and applied it to mutation data from the BXDs. We discovered an additional C>A mutator locus on chromosome 6 that overlaps Ogg1, a DNA glycosylase involved in the same base-excision repair network as Mutyh [4]. Its effect depended on the presence of a mutator allele near Mutyh, and BXDs with mutator alleles at both loci had greater numbers of C>A mutations than those with mutator alleles at either locus alone. Our new methods for analyzing mutation spectra reveal evidence of epistasis between germline mutator alleles and may be applicable to mutation data from humans and other model organisms.
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Affiliation(s)
| | - Aaron R. Quinlan
- Department of Human Genetics, University of Utah; Department of Biomedical Informatics, University of Utah · Funded by NIH/NHGRI R01HG012252
| | - Kelley Harris
- Department of Genome Sciences, University of Washington · Funded by NIH/NIGMS R35GM133428; Burroughs Wellcome Career Award at the Scientific Interface; Searle Scholarship; Pew Scholarship; Sloan Fellowship; Allen Discovery Center for Cell Lineage Tracing
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5
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Krämer OH, Diehl T, Roos WP. Assessing the Effect of Histone Deacetylase Inhibitors on DNA Double-Strand Break Repair by Nonhomologous End Joining. Methods Mol Biol 2023; 2589:293-302. [PMID: 36255632 DOI: 10.1007/978-1-0716-2788-4_19] [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: 06/16/2023]
Abstract
This book chapter describes a plasmid-based reporter method, first described by Bennardo et al. (2008) that we use in our laboratory for determining the activity of the repair of DNA double-strand breaks by nonhomologous end joining. This method can be used to measure the impact of epigenetic modifiers of the histone deacetylase family on this DNA repair pathway by flow cytometry.
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Affiliation(s)
- Oliver H Krämer
- Institute of Toxicology, University Medical Center Mainz, Mainz, Germany
| | - Tamara Diehl
- Institute of Toxicology, University Medical Center Mainz, Mainz, Germany
| | - Wynand P Roos
- Institute of Toxicology, University Medical Center Mainz, Mainz, Germany.
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6
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Lié O, Renault S, Augé-Gouillou C. SETMAR, a case of primate co-opted genes: towards new perspectives. Mob DNA 2022; 13:9. [PMID: 35395947 PMCID: PMC8994322 DOI: 10.1186/s13100-022-00267-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2021] [Accepted: 03/28/2022] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND We carry out a review of the history and biological activities of one domesticated gene in higher primates, SETMAR, by discussing current controversies. Our purpose is to open a new outlook that will serve as a framework for future work about SETMAR, possibly in the field of cognition development. MAIN BODY What is newly important about SETMAR can be summarized as follows: (1) the whole protein sequence is under strong purifying pressure; (2) its role is to strengthen existing biological functions rather than to provide new ones; (3) it displays a tissue-specific pattern of expression, at least for the alternative-splicing it undergoes. Studies reported here demonstrate that SETMAR protein(s) may be involved in essential networks regulating replication, transcription and translation. Moreover, during embryogenesis, SETMAR appears to contribute to brain development. SHORT CONCLUSION Our review underlines for the first time that SETMAR directly interacts with genes involved in brain functions related to vocalization and vocal learning. These findings pave the way for future works regarding SETMAR and the development of cognitive abilities in higher primates.
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Affiliation(s)
- Oriane Lié
- UMR 1253, iBrain, Université de Tours, Inserm, Tours, France.,iBrain, Team Neurogenomics and Neuronal physiopathology, Faculty of Medicine, 10 Bd Tonnellé, Cedex 1, 37032, Tours, France
| | - Sylvaine Renault
- UMR 1253, iBrain, Université de Tours, Inserm, Tours, France.,iBrain, Team Neurogenomics and Neuronal physiopathology, Faculty of Medicine, 10 Bd Tonnellé, Cedex 1, 37032, Tours, France
| | - Corinne Augé-Gouillou
- UMR 1253, iBrain, Université de Tours, Inserm, Tours, France. .,iBrain, Team Neurogenomics and Neuronal physiopathology, Faculty of Medicine, 10 Bd Tonnellé, Cedex 1, 37032, Tours, France.
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7
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Nickoloff JA, Sharma N, Taylor L, Allen SJ, Lee SH, Hromas R. Metnase and EEPD1: DNA Repair Functions and Potential Targets in Cancer Therapy. Front Oncol 2022; 12:808757. [PMID: 35155245 PMCID: PMC8831698 DOI: 10.3389/fonc.2022.808757] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2021] [Accepted: 01/12/2022] [Indexed: 12/30/2022] Open
Abstract
Cells respond to DNA damage by activating signaling and DNA repair systems, described as the DNA damage response (DDR). Clarifying DDR pathways and their dysregulation in cancer are important for understanding cancer etiology, how cancer cells exploit the DDR to survive endogenous and treatment-related stress, and to identify DDR targets as therapeutic targets. Cancer is often treated with genotoxic chemicals and/or ionizing radiation. These agents are cytotoxic because they induce DNA double-strand breaks (DSBs) directly, or indirectly by inducing replication stress which causes replication fork collapse to DSBs. EEPD1 and Metnase are structure-specific nucleases, and Metnase is also a protein methyl transferase that methylates histone H3 and itself. EEPD1 and Metnase promote repair of frank, two-ended DSBs, and both promote the timely and accurate restart of replication forks that have collapsed to single-ended DSBs. In addition to its roles in HR, Metnase also promotes DSB repair by classical non-homologous recombination, and chromosome decatenation mediated by TopoIIα. Although mutations in Metnase and EEPD1 are not common in cancer, both proteins are frequently overexpressed, which may help tumor cells manage oncogenic stress or confer resistance to therapeutics. Here we focus on Metnase and EEPD1 DNA repair pathways, and discuss opportunities for targeting these pathways to enhance cancer therapy.
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Affiliation(s)
- Jac A Nickoloff
- Department of Environmental and Radiological Health Sciences, Colorado State University, Fort Collins, CO, United States
| | - Neelam Sharma
- Department of Environmental and Radiological Health Sciences, Colorado State University, Fort Collins, CO, United States
| | - Lynn Taylor
- Department of Environmental and Radiological Health Sciences, Colorado State University, Fort Collins, CO, United States
| | - Sage J Allen
- Department of Environmental and Radiological Health Sciences, Colorado State University, Fort Collins, CO, United States
| | - Suk-Hee Lee
- Department of Biochemistry & Molecular Biology, Indiana University School of Medicine, Indianapolis, IN, United States
| | - Robert Hromas
- Division of Hematology and Medical Oncology, Department of Medicine and the Mays Cancer Center, University of Texas Health Science Center, San Antonio, TX, United States
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8
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Lié O, Virolle T, Gabut M, Pasquier C, Zemmoura I, Augé-Gouillou C. SETMAR Shorter Isoform: A New Prognostic Factor in Glioblastoma. Front Oncol 2022; 11:638397. [PMID: 35047379 PMCID: PMC8761672 DOI: 10.3389/fonc.2021.638397] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2020] [Accepted: 11/03/2021] [Indexed: 12/27/2022] Open
Abstract
Recent evidence suggests that the chimeric protein SETMAR is a factor of interest in cancer, especially in glioblastoma. However, little is known about the expression of this protein in glioblastoma tissues, and no study has been done to assess if SETMAR could be a prognostic and/or diagnostic marker of glioblastoma. We analyzed protein extracts of 47 glioblastoma samples coming from a local and a national cohort of patients. From the local cohort, we obtained localized biopsies from the central necrosis area, the tumor, and the perilesional brain. From the French Glioblastoma Biobank (FGB), we obtained three types of samples: from the same tumors before and after treatment, from long survivors, and from very short survivors. We studied the correlations between SETMAR amounts, clinical profiles of patients and other associated proteins (PTN, snRNP70 and OLIG2). In glioblastoma tissues, the shorter isoform of SETMAR (S-SETMAR) was predominant over the full-length isoform (FL-SETMAR), and the expression of both SETMAR variants was higher in the tumor compared to the perilesional tissues. Data from the FGB showed that SETMAR amounts were not different between the initial tumors and tumor relapses after treatment. These data also showed a trend toward higher amounts of S-SETMAR in long survivors. In localized biopsies, we found a positive correlation between good prognosis and large amounts of S-SETMAR in the perilesional area. This is the main result presented here: survival in Glioblastoma is correlated with amounts of S-SETMAR in perilesional brain, which should be considered as a new relevant prognosis marker.
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Affiliation(s)
- Oriane Lié
- UMR 1253, iBrain, Université de Tours, Inserm, Tours, France
| | - Thierry Virolle
- Institut de Biologie Valrose, Université Côte D’Azur, CNRS, INSERM, Nice, France
| | - Mathieu Gabut
- INSERM 1052, CNRS 5286, Cancer Research Center of Lyon, Centre Léon Bérard, Lyon, France
- Université Claude Bernard Lyon 1, Villeurbanne, France
| | | | - Ilyess Zemmoura
- UMR 1253, iBrain, Université de Tours, Inserm, Tours, France
- Service de Neurochirurgie, CHRU de Tours, Tours, France
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9
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Tellier M. Structure, Activity, and Function of SETMAR Protein Lysine Methyltransferase. Life (Basel) 2021; 11:life11121342. [PMID: 34947873 PMCID: PMC8704517 DOI: 10.3390/life11121342] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2021] [Revised: 11/30/2021] [Accepted: 12/01/2021] [Indexed: 12/21/2022] Open
Abstract
SETMAR is a protein lysine methyltransferase that is involved in several DNA processes, including DNA repair via the non-homologous end joining (NHEJ) pathway, regulation of gene expression, illegitimate DNA integration, and DNA decatenation. However, SETMAR is an atypical protein lysine methyltransferase since in anthropoid primates, the SET domain is fused to an inactive DNA transposase. The presence of the DNA transposase domain confers to SETMAR a DNA binding activity towards the remnants of its transposable element, which has resulted in the emergence of a gene regulatory function. Both the SET and the DNA transposase domains are involved in the different cellular roles of SETMAR, indicating the presence of novel and specific functions in anthropoid primates. In addition, SETMAR is dysregulated in different types of cancer, indicating a potential pathological role. While some light has been shed on SETMAR functions, more research and new tools are needed to better understand the cellular activities of SETMAR and to investigate the therapeutic potential of SETMAR.
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Affiliation(s)
- Michael Tellier
- Sir William Dunn School of Pathology, University of Oxford, South Parks Road, Oxford OX1 3RE, UK
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10
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Klaric JA, Wüst S, Panier S. New Faces of old Friends: Emerging new Roles of RNA-Binding Proteins in the DNA Double-Strand Break Response. Front Mol Biosci 2021; 8:668821. [PMID: 34026839 PMCID: PMC8138124 DOI: 10.3389/fmolb.2021.668821] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2021] [Accepted: 04/22/2021] [Indexed: 12/14/2022] Open
Abstract
DNA double-strand breaks (DSBs) are highly cytotoxic DNA lesions. To protect genomic stability and ensure cell homeostasis, cells mount a complex signaling-based response that not only coordinates the repair of the broken DNA strand but also activates cell cycle checkpoints and, if necessary, induces cell death. The last decade has seen a flurry of studies that have identified RNA-binding proteins (RBPs) as novel regulators of the DSB response. While many of these RBPs have well-characterized roles in gene expression, it is becoming increasingly clear that they also have non-canonical functions in the DSB response that go well beyond transcription, splicing and mRNA processing. Here, we review the current understanding of how RBPs are integrated into the cellular response to DSBs and describe how these proteins directly participate in signal transduction, amplification and repair at damaged chromatin. In addition, we discuss the implications of an RBP-mediated DSB response for genome instability and age-associated diseases such as cancer and neurodegeneration.
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Affiliation(s)
- Julie A Klaric
- Max Planck Institute for Biology of Ageing, Cologne, Germany
| | - Stas Wüst
- Max Planck Institute for Biology of Ageing, Cologne, Germany
| | - Stephanie Panier
- Max Planck Institute for Biology of Ageing, Cologne, Germany.,Cologne Cluster of Excellence in Cellular Stress Responses in Aging-Associated Diseases (CECAD) Research Center, University of Cologne, Cologne, Germany
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11
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Antoine-Lorquin A, Arensburger P, Arnaoty A, Asgari S, Batailler M, Beauclair L, Belleannée C, Buisine N, Coustham V, Guyetant S, Helou L, Lecomte T, Pitard B, Stévant I, Bigot Y. Two repeated motifs enriched within some enhancers and origins of replication are bound by SETMAR isoforms in human colon cells. Genomics 2021; 113:1589-1604. [PMID: 33812898 DOI: 10.1016/j.ygeno.2021.03.032] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2020] [Revised: 03/25/2021] [Accepted: 03/30/2021] [Indexed: 11/15/2022]
Abstract
Setmar is a gene specific to simian genomes. The function(s) of its isoforms are poorly understood and their existence in healthy tissues remains to be validated. Here we profiled SETMAR expression and its genome-wide binding landscape in colon tissue. We found isoforms V3 and V6 in healthy and tumour colon tissues as well as incell lines. In two colorectal cell lines SETMAR binds to several thousand Hsmar1 and MADE1 terminal ends, transposons mostly located in non-genic regions of active chromatin including in enhancers. It also binds to a 12-bp motifs similar to an inner motif in Hsmar1 and MADE1 terminal ends. This motif is interspersed throughout the genome and is enriched in GC-rich regions as well as in CpG islands that contain constitutive replication origins. It is also found in enhancers other than those associated with Hsmar1 and MADE1. The role of SETMAR in the expression of genes, DNA replication and in DNA repair are discussed.
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Affiliation(s)
| | - Peter Arensburger
- Biological Sciences Department, California State Polytechnic University, Pomona, CA 91768, - United States
| | - Ahmed Arnaoty
- EA GICC, 7501, CHRU de Tours, 37044 TOURS, Cedex 09, France
| | - Sassan Asgari
- School of Biological Sciences, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Martine Batailler
- PRC, UMR INRA 0085, CNRS 7247, Centre INRA Val de Loire, 37380 Nouzilly, France
| | - Linda Beauclair
- PRC, UMR INRA 0085, CNRS 7247, Centre INRA Val de Loire, 37380 Nouzilly, France
| | | | - Nicolas Buisine
- UMR CNRS 7221, Muséum National d'Histoire Naturelle, 75005 Paris, France
| | | | - Serge Guyetant
- Tumorothèque du CHRU de Tours, 37044 Tours, Cedex, France
| | - Laura Helou
- PRC, UMR INRA 0085, CNRS 7247, Centre INRA Val de Loire, 37380 Nouzilly, France
| | | | - Bruno Pitard
- Université de Nantes, CNRS ERL6001, Inserm 1232, CRCINA, F-44000 Nantes, France
| | - Isabelle Stévant
- Institut de Génomique Fonctionnelle de Lyon, Univ Lyon, CNRS UMR 5242, Ecole Normale Supérieure de Lyon, Université Claude Bernard Lyon, 1, 46 allée d'Italie, 69364 Lyon, France
| | - Yves Bigot
- PRC, UMR INRA 0085, CNRS 7247, Centre INRA Val de Loire, 37380 Nouzilly, France.
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12
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Stinson BM, Loparo JJ. Repair of DNA Double-Strand Breaks by the Nonhomologous End Joining Pathway. Annu Rev Biochem 2021; 90:137-164. [PMID: 33556282 DOI: 10.1146/annurev-biochem-080320-110356] [Citation(s) in RCA: 74] [Impact Index Per Article: 24.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
DNA double-strand breaks pose a serious threat to genome stability. In vertebrates, these breaks are predominantly repaired by nonhomologous end joining (NHEJ), which pairs DNA ends in a multiprotein synaptic complex to promote their direct ligation. NHEJ is a highly versatile pathway that uses an array of processing enzymes to modify damaged DNA ends and enable their ligation. The mechanisms of end synapsis and end processing have important implications for genome stability. Rapid and stable synapsis is necessary to limit chromosome translocations that result from the mispairing of DNA ends. Furthermore, end processing must be tightly regulated to minimize mutations at the break site. Here, we review our current mechanistic understanding of vertebrate NHEJ, with a particular focus on end synapsis and processing.
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Affiliation(s)
- Benjamin M Stinson
- Department of Biological Chemistry and Molecular Pharmacology, Blavatnik Institute, Harvard Medical School, Boston, Massachusetts 02115, USA; ,
| | - Joseph J Loparo
- Department of Biological Chemistry and Molecular Pharmacology, Blavatnik Institute, Harvard Medical School, Boston, Massachusetts 02115, USA; ,
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13
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Sharma N, Speed MC, Allen CP, Maranon DG, Williamson E, Singh S, Hromas R, Nickoloff JA. Distinct roles of structure-specific endonucleases EEPD1 and Metnase in replication stress responses. NAR Cancer 2020; 2:zcaa008. [PMID: 32743552 PMCID: PMC7380491 DOI: 10.1093/narcan/zcaa008] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2019] [Revised: 05/20/2020] [Accepted: 05/31/2020] [Indexed: 12/16/2022] Open
Abstract
Accurate DNA replication and segregation are critical for maintaining genome integrity and suppressing cancer. Metnase and EEPD1 are DNA damage response (DDR) proteins frequently dysregulated in cancer and implicated in cancer etiology and tumor response to genotoxic chemo- and radiotherapy. Here, we examine the DDR in human cell lines with CRISPR/Cas9 knockout of Metnase or EEPD1. The knockout cell lines exhibit slightly slower growth rates, significant hypersensitivity to replication stress, increased genome instability and distinct alterations in DDR signaling. Metnase and EEPD1 are structure-specific nucleases. EEPD1 is recruited to and cleaves stalled forks to initiate fork restart by homologous recombination. Here, we demonstrate that Metnase is also recruited to stalled forks where it appears to dimethylate histone H3 lysine 36 (H3K36me2), raising the possibility that H3K36me2 promotes DDR factor recruitment or limits nucleosome eviction to protect forks from nucleolytic attack. We show that stalled forks are cleaved normally in the absence of Metnase, an important and novel result because a prior study indicated that Metnase nuclease is important for timely fork restart. A double knockout was as sensitive to etoposide as either single knockout, suggesting a degree of epistasis between Metnase and EEPD1. We propose that EEPD1 initiates fork restart by cleaving stalled forks, and that Metnase may promote fork restart by processing homologous recombination intermediates and/or inducing H3K36me2 to recruit DDR factors. By accelerating fork restart, Metnase and EEPD1 reduce the chance that stalled replication forks will adopt toxic or genome-destabilizing structures, preventing genome instability and cancer. Metnase and EEPD1 are overexpressed in some cancers and thus may also promote resistance to genotoxic therapeutics.
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Affiliation(s)
- Neelam Sharma
- Department of Environmental and Radiological Health Sciences, Colorado State University, 1618 Campus Delivery, Fort Collins, CO 80523-1618, USA
| | - Michael C Speed
- Department of Environmental and Radiological Health Sciences, Colorado State University, 1618 Campus Delivery, Fort Collins, CO 80523-1618, USA
| | - Christopher P Allen
- Department of Microbiology, Immunology, and Pathology, Colorado State University, 1601Campus Delivery, Fort Collins, CO 80523-1601, USA
| | - David G Maranon
- Department of Environmental and Radiological Health Sciences, Colorado State University, 1618 Campus Delivery, Fort Collins, CO 80523-1618, USA
| | - Elizabeth Williamson
- Division of Hematology and Medical Oncology, Department of Medicine, University of Texas HealthScience Center, 7703 Floyd Curl Drive, San Antonio, TX 78229, USA
| | - Sudha Singh
- Division of Hematology and Medical Oncology, Department of Medicine, University of Texas HealthScience Center, 7703 Floyd Curl Drive, San Antonio, TX 78229, USA
| | - Robert Hromas
- Division of Hematology and Medical Oncology, Department of Medicine, University of Texas HealthScience Center, 7703 Floyd Curl Drive, San Antonio, TX 78229, USA
| | - Jac A Nickoloff
- Department of Environmental and Radiological Health Sciences, Colorado State University, 1618 Campus Delivery, Fort Collins, CO 80523-1618, USA
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14
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Tellier M, Chalmers R. The roles of the human SETMAR (Metnase) protein in illegitimate DNA recombination and non-homologous end joining repair. DNA Repair (Amst) 2019; 80:26-35. [PMID: 31238295 PMCID: PMC6715855 DOI: 10.1016/j.dnarep.2019.06.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2019] [Revised: 06/18/2019] [Accepted: 06/18/2019] [Indexed: 02/07/2023]
Abstract
Full length SETMAR expression has no effect on DNA repair and integration in vivo. SETMAR putative nuclease activity is not required in vivo. Separate expression of the SET and MAR domains affects DNA repair and integration. SETMAR isoform with a truncated SET-domain is specific to species containing the MAR domain.
SETMAR is a fusion between a SET-domain methyltransferase gene and a mariner-family transposase gene, which is specific to anthropoid primates. However, the ancestral SET gene is present in all other mammals and birds. SETMAR is reported to be involved in transcriptional regulation and a diverse set of reactions related to DNA repair. Since the transcriptional effects of SETMAR depend on site-specific DNA binding, and are perturbed by inactivating the methyltransferase, we wondered whether we could differentiate the effects of the SET and MAR domains in DNA repair assays. We therefore generated several stable U2OS cell lines expressing either wild type SETMAR or truncation or point mutant variants. We tested these cell lines with in vivo plasmid-based assays to determine the relevance of the different domains and activities of SETMAR in DNA repair. Contrary to previous reports, we found that wild type SETMAR had little to no effect on the rate of cell division, DNA integration into the genome or non-homologous end joining. Also contrary to previous reports, we failed to detect any effect of a strong active-site mutation that should have knocked out the putative nuclease activity of SETMAR.
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Affiliation(s)
- Michael Tellier
- School of Life Sciences, University of Nottingham, Queen's Medical Centre, Nottingham, NG7 2UH, UK.
| | - Ronald Chalmers
- School of Life Sciences, University of Nottingham, Queen's Medical Centre, Nottingham, NG7 2UH, UK.
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Dussaussois-Montagne A, Jaillet J, Babin L, Verrelle P, Karayan-Tapon L, Renault S, Rousselot-Denis C, Zemmoura I, Augé-Gouillou C. SETMAR isoforms in glioblastoma: A matter of protein stability. Oncotarget 2017; 8:9835-9848. [PMID: 28038463 PMCID: PMC5354774 DOI: 10.18632/oncotarget.14218] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2016] [Accepted: 12/05/2016] [Indexed: 01/10/2023] Open
Abstract
Glioblastomas (GBMs) are the most frequent and the most aggressive brain tumors, known for their chemo- and radio-resistance, making them often incurable. We also know that SETMAR is a protein involved in chromatin dynamics and genome plasticity, of which overexpression confers chemo- and radio-resistance to some tumors. The relationships between SETMAR and GBM have never been explored. To fill this gap, we define the SETMAR status of 44 resected tumors and of GBM derived cells, at both the mRNA and the protein levels. We identify a new, small SETMAR protein (so called SETMAR-1200), enriched in GBMs and GBM stem cells as compared to the regular enzyme (SETMAR-2100). We show that SETMAR-1200 is able to increase DNA repair by non-homologous end-joining, albeit with a lower efficiency than the regular SETMAR protein. Interestingly, the regular/small ratio of SETMAR in GBM cells changes depending on cell type, providing evidence that SETMAR expression is regulated by alternative splicing. We also demonstrate that SETMAR expression can be regulated by the use of an alternative ATG. In conclusion, various SETMAR proteins can be synthesized in human GBM that may each have specific biophysical and/or biochemical properties and characteristics. Among them, the small SETMAR may play a role in GBMs biogenesis. On this basis, we would like to consider SETMAR-1200 as a new potential therapeutic target to investigate, in addition to the regular SETMAR protein already considered by others.
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Affiliation(s)
| | - Jérôme Jaillet
- EA 6306 IGC, University François Rabelais, 37200 Tours, France
| | - Laetitia Babin
- EA 6306 IGC, University François Rabelais, 37200 Tours, France
- UMR CNRS 7292 GICC, University François Rabelais, 37000 Tours, France
| | - Pierre Verrelle
- EA 7283 CREaT, Université d′Auvergne, BP 10448, 63000 Clermont-Ferrand, France
- Institut Curie, Dpt d'Oncologie Radiothérapique, 75005 Paris, France
- Centre Jean Perrin, Service Radiothérapie, Laboratoire de Radio-Oncologie Expérimentale, 63000 Clermont-Ferrand, France
| | - Lucie Karayan-Tapon
- INSERM U1084, Laboratoire de Neurosciences Expérimentales et Cliniques, F-86021 Poitiers, France
- University of Poitiers, F-86022 Poitiers, France
- CHU of Poitiers, Laboratoire de Cancérologie Biologique, F-86021 Poitiers, France
| | | | | | - Ilyess Zemmoura
- INSERM U930 Imagerie & Cerveau, University François Rabelais, 37000 Tours, France
- CHRU of Tours, Service de Neurochirurgie, 37000 Tours, France
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16
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Kim HS, Nickoloff JA, Wu Y, Williamson EA, Sidhu GS, Reinert BL, Jaiswal AS, Srinivasan G, Patel B, Kong K, Burma S, Lee SH, Hromas RA. Endonuclease EEPD1 Is a Gatekeeper for Repair of Stressed Replication Forks. J Biol Chem 2017; 292:2795-2804. [PMID: 28049724 PMCID: PMC5314175 DOI: 10.1074/jbc.m116.758235] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2016] [Revised: 12/29/2016] [Indexed: 01/21/2023] Open
Abstract
Replication is not as continuous as once thought, with DNA damage frequently stalling replication forks. Aberrant repair of stressed replication forks can result in cell death or genome instability and resulting transformation to malignancy. Stressed replication forks are most commonly repaired via homologous recombination (HR), which begins with 5′ end resection, mediated by exonuclease complexes, one of which contains Exo1. However, Exo1 requires free 5′-DNA ends upon which to act, and these are not commonly present in non-reversed stalled replication forks. To generate a free 5′ end, stalled replication forks must therefore be cleaved. Although several candidate endonucleases have been implicated in cleavage of stalled replication forks to permit end resection, the identity of such an endonuclease remains elusive. Here we show that the 5′-endonuclease EEPD1 cleaves replication forks at the junction between the lagging parental strand and the unreplicated DNA parental double strands. This cleavage creates the structure that Exo1 requires for 5′ end resection and HR initiation. We observed that EEPD1 and Exo1 interact constitutively, and Exo1 repairs stalled replication forks poorly without EEPD1. Thus, EEPD1 performs a gatekeeper function for replication fork repair by mediating the fork cleavage that permits initiation of HR-mediated repair and restart of stressed forks.
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Affiliation(s)
- Hyun-Suk Kim
- From the Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, Indiana 46202
| | - Jac A Nickoloff
- the Department of Environmental and Radiological Health Sciences, Colorado State University, Fort Collins, Colorado 80523
| | - Yuehan Wu
- the Department of Medicine and the Cancer Center, University of Florida Health, Gainesville, Florida 32610, and
| | - Elizabeth A Williamson
- the Department of Medicine and the Cancer Center, University of Florida Health, Gainesville, Florida 32610, and
| | - Gurjit Singh Sidhu
- the Department of Medicine and the Cancer Center, University of Florida Health, Gainesville, Florida 32610, and
| | - Brian L Reinert
- the Department of Medicine and the Cancer Center, University of Florida Health, Gainesville, Florida 32610, and
| | - Aruna S Jaiswal
- the Department of Medicine and the Cancer Center, University of Florida Health, Gainesville, Florida 32610, and
| | - Gayathri Srinivasan
- the Department of Medicine and the Cancer Center, University of Florida Health, Gainesville, Florida 32610, and
| | - Bhavita Patel
- the Department of Medicine and the Cancer Center, University of Florida Health, Gainesville, Florida 32610, and
| | - Kimi Kong
- the Department of Medicine and the Cancer Center, University of Florida Health, Gainesville, Florida 32610, and
| | - Sandeep Burma
- the Department of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas, Texas 75390
| | - Suk-Hee Lee
- From the Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, Indiana 46202,
| | - Robert A Hromas
- the Department of Medicine and the Cancer Center, University of Florida Health, Gainesville, Florida 32610, and
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Kim HS, Williamson EA, Nickoloff JA, Hromas RA, Lee SH. Metnase Mediates Loading of Exonuclease 1 onto Single Strand Overhang DNA for End Resection at Stalled Replication Forks. J Biol Chem 2016; 292:1414-1425. [PMID: 27974460 DOI: 10.1074/jbc.m116.745646] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2016] [Revised: 12/13/2016] [Indexed: 11/06/2022] Open
Abstract
Stalling at DNA replication forks generates stretches of single-stranded (ss) DNA on both strands that are exposed to nucleolytic degradation, potentially compromising genome stability. One enzyme crucial for DNA replication fork repair and restart of stalled forks in human is Metnase (also known as SETMAR), a chimeric fusion protein consisting of a su(var)3-9, enhancer-of-zeste and trithorax (SET) histone methylase and transposase nuclease domain. We previously showed that Metnase possesses a unique fork cleavage activity necessary for its function in replication restart and that its SET domain is essential for recovery from hydroxyurea-induced DNA damage. However, its exact role in replication restart is unclear. In this study, we show that Metnase associates with exonuclease 1 (Exo1), a 5'-exonuclease crucial for 5'-end resection to mediate DNA processing at stalled forks. Metnase DNA cleavage activity was not required for Exo1 5'-exonuclease activity on the lagging strand daughter DNA, but its DNA binding activity mediated loading of Exo1 onto ssDNA overhangs. Metnase-induced enhancement of Exo1-mediated DNA strand resection required the presence of these overhangs but did not require Metnase's DNA cleavage activity. These results suggest that Metnase enhances Exo1-mediated exonuclease activity on the lagging strand DNA by facilitating Exo1 loading onto a single strand gap at the stalled replication fork.
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Affiliation(s)
- Hyun-Suk Kim
- From the Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, Indiana 46202
| | - Elizabeth A Williamson
- the Department of Medicine, University of Florida and Shands Health Care System, Gainesville, Florida 32610, and
| | - Jac A Nickoloff
- the Department of Environmental and Radiological Health Sciences, Colorado State University, Fort Collins, Colorado 80523
| | - Robert A Hromas
- the Department of Medicine, University of Florida and Shands Health Care System, Gainesville, Florida 32610, and
| | - Suk-Hee Lee
- From the Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, Indiana 46202,
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18
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Chen Q, Georgiadis M. Crystallization of and selenomethionine phasing strategy for a SETMAR-DNA complex. Acta Crystallogr F Struct Biol Commun 2016; 72:713-9. [PMID: 27599863 PMCID: PMC5012212 DOI: 10.1107/s2053230x16012723] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2016] [Accepted: 08/06/2016] [Indexed: 11/10/2022] Open
Abstract
Transposable elements have played a critical role in the creation of new genes in all higher eukaryotes, including humans. Although the chimeric fusion protein SETMAR is no longer active as a transposase, it contains both the DNA-binding domain (DBD) and catalytic domain of the Hsmar1 transposase. The amino-acid sequence of the DBD has been virtually unchanged in 50 million years and, as a consequence, SETMAR retains its sequence-specific binding to the ancestral Hsmar1 terminal inverted repeat (TIR) sequence. Thus, the DNA-binding activity of SETMAR is likely to have an important biological function. To determine the structural basis for the recognition of TIR DNA by SETMAR, the design of TIR-containing oligonucleotides and SETMAR DBD variants, crystallization of DBD-DNA complexes, phasing strategies and initial phasing experiments are reported here. An unexpected finding was that oligonucleotides containing two BrdUs in place of thymidines produced better quality crystals in complex with SETMAR than their natural counterparts.
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Affiliation(s)
- Qiujia Chen
- Biochemistry and Molecular Biology, Indiana University School of Medicine, 635 Barnhill Drive, Indianapolis, IN 46202, USA
| | - Millie Georgiadis
- Biochemistry and Molecular Biology, Indiana University School of Medicine, 635 Barnhill Drive, Indianapolis, IN 46202, USA
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End-processing nucleases and phosphodiesterases: An elite supporting cast for the non-homologous end joining pathway of DNA double-strand break repair. DNA Repair (Amst) 2016; 43:57-68. [PMID: 27262532 DOI: 10.1016/j.dnarep.2016.05.011] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2016] [Accepted: 05/05/2016] [Indexed: 11/20/2022]
Abstract
Nonhomologous end joining (NHEJ) is an error-prone DNA double-strand break repair pathway that is active throughout the cell cycle. A substantial fraction of NHEJ repair events show deletions and, less often, insertions in the repair joints, suggesting an end-processing step comprising the removal of mismatched or damaged nucleotides by nucleases and other phosphodiesterases, as well as subsequent strand extension by polymerases. A wide range of nucleases, including Artemis, Metnase, APLF, Mre11, CtIP, APE1, APE2 and WRN, are biochemically competent to carry out such double-strand break end processing, and have been implicated in NHEJ by at least circumstantial evidence. Several additional DNA end-specific phosphodiesterases, including TDP1, TDP2 and aprataxin are available to resolve various non-nucleotide moieties at DSB ends. This review summarizes the biochemical specificities of these enzymes and the evidence for their participation in the NHEJ pathway.
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HROMAS ROBERT, WILLIAMSON ELIZABETH, LEE SUKHEE, NICKOLOFF JAC. PREVENTING THE CHROMOSOMAL TRANSLOCATIONS THAT CAUSE CANCER. TRANSACTIONS OF THE AMERICAN CLINICAL AND CLIMATOLOGICAL ASSOCIATION 2016; 127:176-195. [PMID: 28066052 PMCID: PMC5216476] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Approximately half of all cancers harbor chromosomal translocations that can either contribute to their origin or govern their subsequent behavior. Chromosomal translocations by definition can only occur when there are two DNA double-strand breaks (DSBs) on distinct chromosomes that are repaired heterologously. Thus, chromosomal translocations are by their very nature problems of DNA DSB repair. Such DNA DSBs can be from internal or external sources. Internal sources of DNA DSBs that can lead to translocations can occur are inappropriate immune receptor gene maturation during V(D)J recombination or heavy-chain switching. Other internal DNA DSBs can come from aberrant DNA structures, or are generated at collapsed and reversed replication forks. External sources of DNA DSBs that can generate chromosomal translocations are ionizing radiation and cancer chemotherapy. There are several known nuclear and chromatin properties that enhance translocations over homologous chromosome DSB repair. The proximity of the region of the heterologous chromosomes to each other increases translocation rates. Histone methylation events at the DSB also influence translocation frequencies. There are four DNA DSB repair pathways, but it appears that only one, alternative non-homologous end-joining (a-NHEJ) can mediate chromosomal translocations. The rate-limiting, initial step of a-NHEJ is the binding of poly-adenosine diphosphate ribose polymerase 1 (PARP1) to the DSB. In our investigation of methods for preventing oncogenic translocations, we discovered that PARP1 was required for translocations. Significantly, the clinically approved PARP1 inhibitors can block the formation of chromosomal translocations, raising the possibility for the first time that secondary oncogenic translocations can be reduced in high risk patients.
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Affiliation(s)
- ROBERT HROMAS
- Correspondence and reprint requests: Robert Hromas, MD, FACP,
Department of Medicine, University of Florida College of Medicine, 1600 SW Archer Rd, Gainesville, FL 32610352-265-0655352-265-1107
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21
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Bonnet A, Servin B, Mulsant P, Mandon-Pepin B. Spatio-Temporal Gene Expression Profiling during In Vivo Early Ovarian Folliculogenesis: Integrated Transcriptomic Study and Molecular Signature of Early Follicular Growth. PLoS One 2015; 10:e0141482. [PMID: 26540452 PMCID: PMC4634757 DOI: 10.1371/journal.pone.0141482] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2015] [Accepted: 10/08/2015] [Indexed: 11/19/2022] Open
Abstract
Background The successful achievement of early ovarian folliculogenesis is important for fertility and reproductive life span. This complex biological process requires the appropriate expression of numerous genes at each developmental stage, in each follicular compartment. Relatively little is known at present about the molecular mechanisms that drive this process, and most gene expression studies have been performed in rodents and without considering the different follicular compartments. Results We used RNA-seq technology to explore the sheep transcriptome during early ovarian follicular development in the two main compartments: oocytes and granulosa cells. We documented the differential expression of 3,015 genes during this phase and described the gene expression dynamic specific to these compartments. We showed that important steps occurred during primary/secondary transition in sheep. We also described the in vivo molecular course of a number of pathways. In oocytes, these pathways documented the chronology of the acquisition of meiotic competence, migration and cellular organization, while in granulosa cells they concerned adhesion, the formation of cytoplasmic projections and steroid synthesis. This study proposes the involvement in this process of several members of the integrin and BMP families. The expression of genes such as Kruppel-like factor 9 (KLF9) and BMP binding endothelial regulator (BMPER) was highlighted for the first time during early follicular development, and their proteins were also predicted to be involved in gene regulation. Finally, we selected a data set of 24 biomarkers that enabled the discrimination of early follicular stages and thus offer a molecular signature of early follicular growth. This set of biomarkers includes known genes such as SPO11 meiotic protein covalently bound to DSB (SPO11), bone morphogenetic protein 15 (BMP15) and WEE1 homolog 2 (S. pombe)(WEE2) which play critical roles in follicular development but other biomarkers are also likely to play significant roles in this process. Conclusions To our knowledge, this is the first in vivo spatio-temporal exploration of transcriptomes derived from early follicles in sheep.
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Affiliation(s)
- Agnes Bonnet
- INRA, UMR 1388 GenPhySE (Génétique, Physiologie et Systèmes d’Elevage), F-31326 Castanet-Tolosan, France
- Université de Toulouse, INP, ENSAT, GenPhySE (Génétique, Physiologie et Systèmes d’Elevage), F-31326 Castanet-Tolosan, France
- Université de Toulouse, INP, ENVT, GenPhySE (Génétique, Physiologie et Systèmes d’Elevage), F-31076 Toulouse, France
- * E-mail:
| | - Bertrand Servin
- INRA, UMR 1388 GenPhySE (Génétique, Physiologie et Systèmes d’Elevage), F-31326 Castanet-Tolosan, France
- Université de Toulouse, INP, ENSAT, GenPhySE (Génétique, Physiologie et Systèmes d’Elevage), F-31326 Castanet-Tolosan, France
- Université de Toulouse, INP, ENVT, GenPhySE (Génétique, Physiologie et Systèmes d’Elevage), F-31076 Toulouse, France
| | - Philippe Mulsant
- INRA, UMR 1388 GenPhySE (Génétique, Physiologie et Systèmes d’Elevage), F-31326 Castanet-Tolosan, France
- Université de Toulouse, INP, ENSAT, GenPhySE (Génétique, Physiologie et Systèmes d’Elevage), F-31326 Castanet-Tolosan, France
- Université de Toulouse, INP, ENVT, GenPhySE (Génétique, Physiologie et Systèmes d’Elevage), F-31076 Toulouse, France
| | - Beatrice Mandon-Pepin
- INRA, UMR1198 Biologie du Développement et de la Reproduction, F-78350 Jouy-en-Josas, France
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22
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Kim HS, Kim SK, Hromas R, Lee SH. The SET Domain Is Essential for Metnase Functions in Replication Restart and the 5' End of SS-Overhang Cleavage. PLoS One 2015; 10:e0139418. [PMID: 26437079 PMCID: PMC4593633 DOI: 10.1371/journal.pone.0139418] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2015] [Accepted: 09/14/2015] [Indexed: 11/19/2022] Open
Abstract
Metnase (also known as SETMAR) is a chimeric SET-transposase protein that plays essential role(s) in non-homologous end joining (NHEJ) repair and replication fork restart. Although the SET domain possesses histone H3 lysine 36 dimethylation (H3K36me2) activity associated with an improved association of early repair components for NHEJ, its role in replication restart is less clear. Here we show that the SET domain is necessary for the recovery from DNA damage at the replication forks following hydroxyurea (HU) treatment. Cells overexpressing the SET deletion mutant caused a delay in fork restart after HU release. Our In vitro study revealed that the SET domain but not the H3K36me2 activity is required for the 5’ end of ss-overhang cleavage with fork and non-fork DNA without affecting the Metnase-DNA interaction. Together, our results suggest that the Metnase SET domain has a positive role in restart of replication fork and the 5’ end of ss-overhang cleavage, providing a new insight into the functional interaction of the SET and the transposase domains.
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Affiliation(s)
- Hyun-Suk Kim
- Department of Biochemistry & Molecular Biology, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
| | - Sung-Kyung Kim
- Department of Biochemistry & Molecular Biology, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
| | - Robert Hromas
- Department of Medicine, University of Florida and Shands Health Care System, Gainesville, Florida, United States of America
| | - Suk-Hee Lee
- Department of Biochemistry & Molecular Biology, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
- Indiana University Simon Cancer Center, Indianapolis, Indiana, United States of America
- * E-mail:
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23
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hPso4/hPrp19: a critical component of DNA repair and DNA damage checkpoint complexes. Oncogene 2015; 35:2279-86. [PMID: 26364595 DOI: 10.1038/onc.2015.321] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2015] [Revised: 07/16/2015] [Accepted: 07/19/2015] [Indexed: 12/15/2022]
Abstract
Genome integrity is vital to cellular homeostasis and its forfeiture is linked to deleterious consequences-cancer, immunodeficiency, genetic disorders and premature aging. The human ubiquitin ligase Pso4/Prp19 has emerged as a critical component of multiple DNA damage response (DDR) signaling networks. It not only senses DNA damage, binds double-stranded DNA in a sequence-independent manner, facilitates processing of damaged DNA, promotes DNA end joining, regulates replication protein A (RPA2) phosphorylation and ubiquitination at damaged DNA, but also regulates RNA splicing and mitotic spindle formation in its integral capacity as a scaffold for a multimeric core complex. Accordingly, by virtue of its regulatory and structural interactions with key proteins critical for genome integrity-DNA double-strand break (DSB) repair, DNA interstrand crosslink repair, repair of stalled replication forks and DNA end joining-it fills a unique niche in restoring genomic integrity after multiple types of DNA damage and thus has a vital role in maintaining chromatin integrity and cellular functions. These properties may underlie its ability to thwart replicative senescence and, not surprisingly, have been linked to the self-renewal and colony-forming ability of murine hematopoietic stem cells. This review highlights recent advances in hPso4 research that provides a fascinating glimpse into the pleiotropic activities of a ubiquitously expressed multifunctional E3 ubiquitin ligase.
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24
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Wei J, Moran T, Zou Z, Qian X, Wang L, Camps C, Hu W, Chaib I, Sanchez B, Xu L, Karachaliou N, Sanchez-Ronco M, Liu B, Rosell R. Customized chemotherapy in metastatic non-small cell lung cancer (NSCLC). Transl Lung Cancer Res 2015; 2:180-8. [PMID: 25806231 DOI: 10.3978/j.issn.2218-6751.2013.02.03] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2013] [Accepted: 02/19/2013] [Indexed: 01/22/2023]
Abstract
Metastatic non-small cell lung cancer (NSCLC) unfortunately remains a lethal disease, despite recent genetic characterization of subclasses of NSCLC, mainly adenocarcinoma, which has led to the development of targeted therapies that improve progression-free survival (PFS). Ultimately, however, patients fatally relapse. In this review we will focus on the search to improve survival for NSCLC patients deemed to be pan-negative for the common driver alterations susceptible to targeted therapy, above all those with EGFR mutations or ALK, ROS or RET translocations. Other uncommon driver mutations such as HER2 and BRAF mutations should be tested in order to rule out targeted treatment before assigning patients to chemotherapy. Chemotherapy yields short lived response with median survival still less than one year. Customized chemotherapy represents one way to attempt to prolong survival, although to date no prospective randomized customized studies have reported sufficient evidence to support this. In one attempt to demonstrate the role of tailoring chemotherapy, the Spanish Lung Cancer Group (SLCG) phase II customized chemotherapy trial (NCT00883480) showed that RAP80, a component of the BRCA1-A complex, influenced outcome in patients with low BRCA1 expression treated with cisplatin/gemcitabine, and in patients with intermediate/high BRCA1 levels receiving cisplatin/docetaxel or docetaxel alone. We are currently performing a prospective, randomized phase III trial comparing non-customized cisplatin/docetaxel with customized therapy in metastatic NSCLC patients (NCT00617656/GECP-BREC) and a parallel phase II study (ChiCTR-TRC-12001860) is being carried out in China (BREC-China) under the auspices of the SLCG.
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Affiliation(s)
- Jia Wei
- Comprehensive Cancer Centre of Drum Tower Hospital, Medical School of Nanjing University, Nanjing 210008, China
| | - Teresa Moran
- Catalan Institute of Oncology, Hospital Germans Trias i Pujol, Ctra Canyet s/n, 08916 Badalona, Spain
| | - Zhengyun Zou
- Comprehensive Cancer Centre of Drum Tower Hospital, Medical School of Nanjing University, Nanjing 210008, China
| | - Xiaoping Qian
- Comprehensive Cancer Centre of Drum Tower Hospital, Medical School of Nanjing University, Nanjing 210008, China
| | - Lifeng Wang
- Comprehensive Cancer Centre of Drum Tower Hospital, Medical School of Nanjing University, Nanjing 210008, China
| | - Carlos Camps
- Hospital General Universitario de Valencia, Av Tres Cruces, s/n, 46014 Valencia, Spain
| | - Wenjing Hu
- Comprehensive Cancer Centre of Drum Tower Hospital, Medical School of Nanjing University, Nanjing 210008, China
| | - Imane Chaib
- Catalan Institute of Oncology, Hospital Germans Trias i Pujol, Ctra Canyet s/n, 08916 Badalona, Spain
| | - Belén Sanchez
- Catalan Institute of Oncology, Hospital Germans Trias i Pujol, Ctra Canyet s/n, 08916 Badalona, Spain
| | - Lixia Xu
- Comprehensive Cancer Centre of Drum Tower Hospital, Medical School of Nanjing University, Nanjing 210008, China
| | - Niki Karachaliou
- Breakthrough Cancer Research Unit, Pangaea Biotech S.L, Quiron Dexeus University Hospital, Sabino Arana 5-19, 08028 Barcelona
| | - María Sanchez-Ronco
- Universidad Alcalá de Henares, Pza. San Diego s/n, 28801 Alcalá de Henares, Madrid, Spain
| | - Baorui Liu
- Comprehensive Cancer Centre of Drum Tower Hospital, Medical School of Nanjing University, Nanjing 210008, China
| | - Rafael Rosell
- Catalan Institute of Oncology, Hospital Germans Trias i Pujol, Ctra Canyet s/n, 08916 Badalona, Spain ; ; Breakthrough Cancer Research Unit, Pangaea Biotech S.L, Quiron Dexeus University Hospital, Sabino Arana 5-19, 08028 Barcelona
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Carlson SM, Moore KE, Sankaran SM, Reynoird N, Elias JE, Gozani O. A Proteomic Strategy Identifies Lysine Methylation of Splicing Factor snRNP70 by the SETMAR Enzyme. J Biol Chem 2015; 290:12040-7. [PMID: 25795785 DOI: 10.1074/jbc.m115.641530] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2015] [Indexed: 11/06/2022] Open
Abstract
The lysine methyltransferase (KMT) SETMAR is implicated in the response to and repair of DNA damage, but its molecular function is not clear. SETMAR has been associated with dimethylation of histone H3 lysine 36 (H3K36) at sites of DNA damage. However, SETMAR does not methylate H3K36 in vitro. This and the observation that SETMAR is not active on nucleosomes suggest that H3K36 methylation is not a physiologically relevant activity. To identify potential non-histone substrates, we utilized a strategy on the basis of quantitative proteomic analysis of methylated lysine. Our approach identified lysine 130 of the mRNA splicing factor snRNP70 as a SETMAR substrate in vitro, and we show that the enzyme primarily generates monomethylation at this position. Furthermore, we show that SETMAR methylates snRNP70 Lys-130 in cells. Because snRNP70 is a key early regulator of 5' splice site selection, our results suggest a model in which methylation of snRNP70 by SETMAR regulates constitutive and/or alternative splicing. In addition, the proteomic strategy described here is broadly applicable and is a promising route for large-scale mapping of KMT substrates.
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Affiliation(s)
| | - Kaitlyn E Moore
- From the Department of Biology and Department of Chemical and Systems Biology, School of Medicine, Stanford University, Stanford, California 94305
| | | | | | - Joshua E Elias
- Department of Chemical and Systems Biology, School of Medicine, Stanford University, Stanford, California 94305
| | - Or Gozani
- From the Department of Biology and ogozani@stanfordedu
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26
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Williamson EA, Wu Y, Singh S, Byrne M, Wray J, Lee SH, Nickoloff JA, Hromas R. The DNA repair component Metnase regulates Chk1 stability. Cell Div 2014; 9:1. [PMID: 25024738 PMCID: PMC4094783 DOI: 10.1186/1747-1028-9-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2014] [Accepted: 06/09/2014] [Indexed: 12/31/2022] Open
Abstract
Chk1 both arrests replication forks and enhances repair of DNA damage by phosphorylation of downstream effectors. Metnase (also termed SETMAR) is a SET histone methylase and transposase nuclease protein that promotes both DNA double strand break (DSB) repair and re-start of stalled replication forks. We previously found that Chk1 phosphorylation of Metnase on S495 enhanced its DNA DSB repair activity but decreased its ability to re-start stalled replication forks. Here we show that phosphorylated Metnase feeds back to increase the half-life of Chk1. Chk1 half-life is regulated by DDB1 targeting it to Cul4A for ubiquitination and destruction. Metnase decreases Chk1 interaction with DDB1, and decreases Chk1 ubiquitination. These data define a novel pathway for Chk1 regulation, whereby a target of Chk1, Metnase, feeds back to amplify Chk1 stability, and therefore enhance replication fork arrest.
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Affiliation(s)
- Elizabeth A Williamson
- Department of Medicine, University of Florida College of Medicine, 1600 Archer Rd SW, Gainesville, FL 32610, USA
| | - Yuehan Wu
- Department of Medicine, University of Florida College of Medicine, 1600 Archer Rd SW, Gainesville, FL 32610, USA
| | - Sudha Singh
- Department of Medicine, University of Florida College of Medicine, 1600 Archer Rd SW, Gainesville, FL 32610, USA
| | - Michael Byrne
- Department of Medicine, University of Florida College of Medicine, 1600 Archer Rd SW, Gainesville, FL 32610, USA
| | - Justin Wray
- Department of Medicine, University of Florida College of Medicine, 1600 Archer Rd SW, Gainesville, FL 32610, USA
| | - Suk-Hee Lee
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Jac A Nickoloff
- Department of Environmental and Radiological Health Sciences, Colorado State University, Fort Collins, CO 80523, USA
| | - Robert Hromas
- Department of Medicine, University of Florida College of Medicine, 1600 Archer Rd SW, Gainesville, FL 32610, USA
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27
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DNA-PK: a dynamic enzyme in a versatile DSB repair pathway. DNA Repair (Amst) 2014; 17:21-9. [PMID: 24680878 DOI: 10.1016/j.dnarep.2014.02.020] [Citation(s) in RCA: 260] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2013] [Revised: 02/17/2014] [Accepted: 02/24/2014] [Indexed: 11/23/2022]
Abstract
DNA double stranded breaks (DSBs) are the most cytoxic DNA lesion as the inability to properly repair them can lead to genomic instability and tumorigenesis. The prominent DSB repair pathway in humans is non-homologous end-joining (NHEJ). In the simplest sense, NHEJ mediates the direct re-ligation of the broken DNA molecule. However, NHEJ is a complex and versatile process that can repair DSBs with a variety of damages and ends via the utilization of a significant number of proteins. In this review we will describe the important factors and mechanisms modulating NHEJ with emphasis given to the versatility of this repair process and the DNA-PK complex.
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28
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Rath A, Hromas R, De Benedetti A. Fidelity of end joining in mammalian episomes and the impact of Metnase on joint processing. BMC Mol Biol 2014; 15:6. [PMID: 24655462 PMCID: PMC3998112 DOI: 10.1186/1471-2199-15-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2013] [Accepted: 03/12/2014] [Indexed: 12/13/2022] Open
Abstract
Background Double Stranded Breaks (DSBs) are the most serious form of DNA damage and are repaired via homologous recombination repair (HRR) or non-homologous end joining (NHEJ). NHEJ predominates in mammalian cells at most stages of the cell cycle, and it is viewed as ‘error-prone’, although this notion has not been sufficiently challenged due to shortcomings of many current systems. Multi-copy episomes provide a large pool of genetic material where repair can be studied, as repaired plasmids can be back-cloned into bacteria and characterized for sequence alterations. Here, we used EBV-based episomes carrying 3 resistance marker genes in repair studies where a single DSB is generated with virally-encoded HO endonuclease cleaving rapidly at high efficiency for a brief time post-infection. We employed PCR and Southern blot to follow the kinetics of repair and formation of processing intermediates, and replica plating to screen for plasmids with altered joints resulting in loss of chloramphenicol resistance. Further, we employed this system to study the role of Metnase. Metnase is only found in humans and primates and is a key component of the NHEJ pathway, but its function is not fully characterized in intact cells. Results We found that repair of episomes by end-joining was highly accurate in 293 T cells that lack Metnase. Less than 10% of the rescued plasmids showed deletions. Instead, HEK293 cells (that do express Metnase) or 293 T transfected with Metnase revealed a large number of rescued plasmids with altered repaired joint, typically in the form of large deletions. Moreover, quantitative PCR and Southern blotting revealed less accurately repaired plasmids in Metnase expressing cells. Conclusions Our careful re-examination of fidelity of NHEJ repair in mammalian cells carrying a 3′ cohesive overhang at the ends revealed that the repair is efficient and highly accurate, and predominant over HRR. However, the background of the cells is important in establishing accuracy; with human cells perhaps surprisingly much more prone to generate deletions at the repaired junctions, if/when Metnase is abundantly expressed.
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Affiliation(s)
| | | | - Arrigo De Benedetti
- Department of Biochemistry and Molecular Biology, Louisiana State University Health Sciences Center, 1501 Kings Highway, Shreveport, LA 71130, USA.
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29
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Waters CA, Strande NT, Wyatt DW, Pryor JM, Ramsden DA. Nonhomologous end joining: a good solution for bad ends. DNA Repair (Amst) 2014; 17:39-51. [PMID: 24630899 DOI: 10.1016/j.dnarep.2014.02.008] [Citation(s) in RCA: 96] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2013] [Revised: 01/27/2014] [Accepted: 02/10/2014] [Indexed: 12/27/2022]
Abstract
Double strand breaks pose unique problems for DNA repair, especially when broken ends possess complex structures that interfere with standard DNA transactions. Nonhomologous end joining can use multiple strategies to solve these problems. It further uses sophisticated means to ensure the strategy chosen provides the ideal balance of flexibility and accuracy.
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Affiliation(s)
- Crystal A Waters
- Department of Biochemistry and Biophysics and Curriculum in Genetics and Molecular Biology, Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, NC 27599, USA.
| | - Natasha T Strande
- Department of Biochemistry and Biophysics and Curriculum in Genetics and Molecular Biology, Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, NC 27599, USA.
| | - David W Wyatt
- Department of Biochemistry and Biophysics and Curriculum in Genetics and Molecular Biology, Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, NC 27599, USA.
| | - John M Pryor
- Department of Biochemistry and Biophysics and Curriculum in Genetics and Molecular Biology, Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, NC 27599, USA.
| | - Dale A Ramsden
- Department of Biochemistry and Biophysics and Curriculum in Genetics and Molecular Biology, Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, NC 27599, USA.
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30
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Kim HS, Chen Q, Kim SK, Nickoloff JA, Hromas R, Georgiadis MM, Lee SH. The DDN catalytic motif is required for Metnase functions in non-homologous end joining (NHEJ) repair and replication restart. J Biol Chem 2014; 289:10930-10938. [PMID: 24573677 PMCID: PMC4036204 DOI: 10.1074/jbc.m113.533216] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Metnase (or SETMAR) arose from a chimeric fusion of the Hsmar1 transposase downstream of a protein methylase in anthropoid primates. Although the Metnase transposase domain has been largely conserved, its catalytic motif (DDN) differs from the DDD motif of related transposases, which may be important for its role as a DNA repair factor and its enzymatic activities. Here, we show that substitution of DDN610 with either DDD610 or DDE610 significantly reduced in vivo functions of Metnase in NHEJ repair and accelerated restart of replication forks. We next tested whether the DDD or DDE mutants cleave single-strand extensions and flaps in partial duplex DNA and pseudo-Tyr structures that mimic stalled replication forks. Neither substrate is cleaved by the DDD or DDE mutant, under the conditions where wild-type Metnase effectively cleaves ssDNA overhangs. We then characterized the ssDNA-binding activity of the Metnase transposase domain and found that the catalytic domain binds ssDNA but not dsDNA, whereas dsDNA binding activity resides in the helix-turn-helix DNA binding domain. Substitution of Asn-610 with either Asp or Glu within the transposase domain significantly reduces ssDNA binding activity. Collectively, our results suggest that a single mutation DDN610 → DDD610, which restores the ancestral catalytic site, results in loss of function in Metnase.
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Affiliation(s)
- Hyun-Suk Kim
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, Indiana 46202
| | - Qiujia Chen
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, Indiana 46202
| | - Sung-Kyung Kim
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, Indiana 46202
| | - Jac A Nickoloff
- Department of Environmental and Radiological Health Sciences, Colorado State University, Fort Collins, Colorado 80523
| | - Robert Hromas
- Department of Medicine, University of Florida and Shands Health Care System, Gainesville, Florida 32610
| | - Millie M Georgiadis
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, Indiana 46202; Department of Chemistry and Chemical Biology, Indiana University Purdue University Indianapolis, Indianapolis, Indiana 46202
| | - Suk-Hee Lee
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, Indiana 46202.
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31
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Byrne M, Wray J, Reinert B, Wu Y, Nickoloff J, Lee SH, Hromas R, Williamson E. Mechanisms of oncogenic chromosomal translocations. Ann N Y Acad Sci 2014; 1310:89-97. [PMID: 24528169 DOI: 10.1111/nyas.12370] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Chromosome translocations are caused by inappropriate religation of two DNA double-strand breaks (DSBs) in heterologous chromosomes. These DSBs can be generated by endogenous or exogenous sources. Endogenous sources of DSBs leading to translocations include inappropriate recombination activating gene (RAG) or activation-induced deaminase (AID) activity during immune receptor maturation. Endogenous DSBs can also occur at noncanonical DNA structures or at collapsed replication forks. Exogenous sources of DSBs leading to translocations include ionizing radiation (IR) and cancer chemotherapy. Spatial proximity of the heterologous chromosomes is also important for translocations. While three distinct pathways for DNA DSB repair exist, mounting evidence supports alternative nonhomologous end joining (aNHEJ) as the predominant pathway through which the majority of translocations occur. Initiated by poly (ADP-ribose) polymerase 1 (PARP1), aNHEJ is utilized less frequently in DNA DSB repair than other forms of DSB repair. We recently found that PARP1 is essential for chromosomal translocations to occur and that small molecule PARP1 inhibitors, already in clinical use, can inhibit translocations generated by IR or topoisomerase II inhibition. These data confirm the central role of PARP1 in aNHEJ-mediated chromosomal translocations and raise the possibility of using clinically available PARP1 inhibitors in patients who are at high risk for secondary oncogenic chromosomal translocations.
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Affiliation(s)
- Michael Byrne
- Department of Medicine, University of Florida College of Medicine, Gainesville, Florida
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32
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Pavelitz T, Gray LT, Padilla SL, Bailey AD, Weiner AM. PGBD5: a neural-specific intron-containing piggyBac transposase domesticated over 500 million years ago and conserved from cephalochordates to humans. Mob DNA 2013; 4:23. [PMID: 24180413 PMCID: PMC3902484 DOI: 10.1186/1759-8753-4-23] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2013] [Accepted: 10/04/2013] [Indexed: 01/01/2023] Open
Abstract
BACKGROUND piggyBac domain (PGBD) transposons are found in organisms ranging from fungi to humans. Three domesticated piggyBac elements have been described. In the ciliates Paramecium tetraurelia and Tetrahymena thermophila, homologs known as piggyMacs excise internal eliminated sequences from germline micronuclear DNA during regeneration of the new somatic macronucleus. In primates, a PGBD3 element inserted into the Cockayne syndrome group B (CSB) gene over 43 Mya serves as an alternative 3' terminal exon, enabling the CSB gene to generate both full length CSB and a conserved CSB-PGBD3 fusion protein that joins an N-terminal CSB domain to the C-terminal transposase domain. RESULTS We describe a fourth domesticated piggyBac element called PGBD5. We show that i) PGBD5 was first domesticated in the common ancestor of the cephalochordate Branchiostoma floridae (aka lancelet or amphioxus) and vertebrates, and is conserved in all vertebrates including lamprey but cannot be found in more basal urochordates, hemichordates, or echinoderms; ii) the lancelet, lamprey, and human PGBD5 genes are syntenic and orthologous; iii) no potentially mobile ancestral PGBD5 elements can be identified in other more deeply rooted organisms; iv) although derived from an IS4-related transposase of the RNase H clan, PGBD5 protein is unlikely to retain enzymatic activity because the catalytic DDD(D) motif is not conserved; v) PGBD5 is preferentially expressed in certain granule cell lineages of the brain and in the central nervous system based on available mouse and human in situ hybridization data, and the tissue-specificity of documented mammalian EST and mRNA clones; vi) the human PGBD5 promoter and gene region is rich in bound regulatory factors including the neuron-restrictive silencer factors NRSF/REST and CoREST, as well as SIN3, KAP1, STAT3, and CTCF; and vii) despite preferential localization within the nucleus, PGBD5 protein is unlikely to bind DNA or chromatin as neither DNase I digestion nor high salt extraction release PGBD5 from fractionated mouse brain nuclei. CONCLUSIONS We speculate that the neural-specific PGBD5 transposase was domesticated >500 My after cephalochordates and vertebrates split from urochordates, and that PGBD5 may have played a role in the evolution of a primitive deuterostome neural network into a centralized nervous system.
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Affiliation(s)
| | | | | | | | - Alan M Weiner
- Department of Biochemistry, School of Medicine, University of Washington, Seattle, WA 98195-7350, USA.
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33
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Trimming of damaged 3' overhangs of DNA double-strand breaks by the Metnase and Artemis endonucleases. DNA Repair (Amst) 2013; 12:422-32. [PMID: 23602515 DOI: 10.1016/j.dnarep.2013.03.005] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2013] [Revised: 03/01/2013] [Accepted: 03/21/2013] [Indexed: 11/22/2022]
Abstract
Both Metnase and Artemis possess endonuclease activities that trim 3' overhangs of duplex DNA. To assess the potential of these enzymes for facilitating resolution of damaged ends during double-strand break rejoining, substrates bearing a variety of normal and structurally modified 3' overhangs were constructed, and treated either with Metnase or with Artemis plus DNA-dependent protein kinase (DNA-PK). Unlike Artemis, which trims long overhangs to 4-5 bases, cleavage by Metnase was more evenly distributed over the length of the overhang, but with significant sequence dependence. In many substrates, Metnase also induced marked cleavage in the double-stranded region within a few bases of the overhang. Like Artemis, Metnase efficiently trimmed overhangs terminated in 3'-phosphoglycolates (PGs), and in some cases the presence of 3'-PG stimulated cleavage and altered its specificity. The nonplanar base thymine glycol in a 3' overhang severely inhibited cleavage by Metnase in the vicinity of the modified base, while Artemis was less affected. Nevertheless, thymine glycol moieties could be removed by Metnase- or Artemis-mediated cleavage at sites farther from the terminus than the lesion itself. In in vitro end-joining systems based on human cell extracts, addition of Artemis, but not Metnase, effected robust trimming of an unligatable 3'-PG overhang, resulting in a dramatic stimulation of ligase IV- and XLF-dependent end joining. Thus, while both Metnase and Artemis are biochemically capable of resolving a variety of damaged DNA ends for the repair of complex double-strand breaks, Artemis appears to act more efficiently in the context of other nonhomologous end joining proteins.
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34
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Detection and repair of ionizing radiation-induced DNA double strand breaks: new developments in nonhomologous end joining. Int J Radiat Oncol Biol Phys 2013; 86:440-9. [PMID: 23433795 DOI: 10.1016/j.ijrobp.2013.01.011] [Citation(s) in RCA: 111] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2012] [Accepted: 01/07/2013] [Indexed: 01/13/2023]
Abstract
DNA damage can occur as a result of endogenous metabolic reactions and replication stress or from exogenous sources such as radiation therapy and chemotherapy. DNA double strand breaks are the most cytotoxic form of DNA damage, and defects in their repair can result in genome instability, a hallmark of cancer. The major pathway for the repair of ionizing radiation-induced DSBs in human cells is nonhomologous end joining. Here we review recent advances on the mechanism of nonhomologous end joining, as well as new findings on its component proteins and regulation.
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35
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Hunt CR, Ramnarain D, Horikoshi N, Iyengar P, Pandita RK, Shay JW, Pandita TK. Histone modifications and DNA double-strand break repair after exposure to ionizing radiations. Radiat Res 2013; 179:383-92. [PMID: 23373901 DOI: 10.1667/rr3308.2] [Citation(s) in RCA: 100] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Ionizing radiation exposure induces highly lethal DNA double-strand breaks (DSBs) in all phases of the cell cycle. After DSBs are detected by the cellular machinery, these breaks are repaired by either of two mechanisms: (1) nonhomologous end joining (NHEJ), which re-ligates the broken ends of the DNA and (2) homologous recombination (HR), that makes use of an undamaged identical DNA sequence as a template to maintain the fidelity of DNA repair. DNA DSB repair must occur within the context of the natural cellular DNA structure. Among the major factors influencing DNA organization are specific histone and nonhistone proteins that form chromatin. The overall chromatin structure regulates DNA damage responses since chromatin status can impede DNA damage site access by repair proteins. During the process of DNA DSB repair, several chromatin alterations are required to sense damage and facilitate accessibility of the repair machinery. The DNA DSB response is also facilitated by hierarchical signaling networks that orchestrate chromatin structural changes that may coordinate cell-cycle checkpoints involving multiple enzymatic activities to repair broken DNA ends. During DNA damage sensing and repair, histones undergo posttranslational modifications (PTMs) including phosphorylation, acetylation, methylation and ubiquitylation. Such histone modifications represent a histone code that directs the recruitment of proteins involved in DNA damage sensing and repair processes. In this review, we summarize histone modifications that occur during DNA DSB repair processes.
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Affiliation(s)
- Clayton R Hunt
- University of Texas Southwestern Medical Center, Dallas, Texas 75390, USA
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36
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Kumar R, Horikoshi N, Singh M, Gupta A, Misra HS, Albuquerque K, Hunt CR, Pandita TK. Chromatin modifications and the DNA damage response to ionizing radiation. Front Oncol 2013; 2:214. [PMID: 23346550 PMCID: PMC3551241 DOI: 10.3389/fonc.2012.00214] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2012] [Accepted: 12/29/2012] [Indexed: 01/01/2023] Open
Abstract
In order to survive, cells have evolved highly effective repair mechanisms to deal with the potentially lethal DNA damage produced by exposure to endogenous as well as exogenous agents. Ionizing radiation exposure induces highly lethal DNA damage, especially DNA double-strand breaks (DSBs), that is sensed by the cellular machinery and then subsequently repaired by either of two different DSB repair mechanisms: (1) non-homologous end joining, which re-ligates the broken ends of the DNA and (2) homologous recombination, that employs an undamaged identical DNA sequence as a template, to maintain the fidelity of DNA repair. Repair of DSBs must occur within the natural context of the cellular DNA which, along with specific proteins, is organized to form chromatin, the overall structure of which can impede DNA damage site access by repair proteins. The chromatin complex is a dynamic structure and is known to change as required for ongoing cellular processes such as gene transcription or DNA replication. Similarly, during the process of DNA damage sensing and repair, chromatin needs to undergo several changes in order to facilitate accessibility of the repair machinery. Cells utilize several factors to modify the chromatin in order to locally open up the structure to reveal the underlying DNA sequence but post-translational modification of the histone components is one of the primary mechanisms. In this review, we will summarize chromatin modifications by the respective chromatin modifying factors that occur during the DNA damage response.
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Affiliation(s)
- Rakesh Kumar
- Department of Radiation Oncology, University of Texas Southwestern Medical Center Dallas, TX, USA
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37
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Strande NT, Waters CA, Ramsden DA. Resolution of complex ends by Nonhomologous end joining - better to be lucky than good? Genome Integr 2012; 3:10. [PMID: 23276302 PMCID: PMC3547747 DOI: 10.1186/2041-9414-3-10] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2012] [Accepted: 12/16/2012] [Indexed: 12/03/2022] Open
Abstract
The Nonhomologous end joining pathway is essential for efficient repair of chromosome double strand breaks. This pathway consequently plays a key role in cellular resistance to break-inducing exogenous agents, as well as in the developmentally-programmed recombinations that are required for adaptive immunity. Chromosome breaks often have complex or “dirty” end structures that can interfere with the critical ligation step in this pathway; we review here how Nonhomologous end joining resolves such breaks.
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Affiliation(s)
- Natasha Tiffany Strande
- Lineberger Comprehensive Cancer Center, Department of Biochemistry and Biophysics and Curriculum in Genetics and Molecular Biology, University of North Carolina, Chapel Hill, North Carolina 27599, USA.
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38
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Povirk LF. Processing of damaged DNA ends for double-strand break repair in mammalian cells. ISRN MOLECULAR BIOLOGY 2012; 2012. [PMID: 24236237 PMCID: PMC3825254 DOI: 10.5402/2012/345805] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Most DNA double-strand breaks (DSBs)formed in a natural environment have chemical modifications at or near the ends that preclude direct religation and require removal or other processing so that rejoining can proceed. Free radical-mediated DSBs typically bear unligatable 3'-phosphate or 3'-phosphoglycolate termini and often have oxidized bases and/or abasic sites near the break. Topoisomerase-mediated DSBs are blocked by covalently bound peptide fragments of the topoisomerase. Enzymes capable of resolving damaged ends include polynucleotide kinase/phosphatase, which restores missing 5'-phosphates and removes 3'-phosphates; tyrosyl-DNA phosphodiesterases I and II (TDP1 and TDP2), which remove peptide fragments of topoisomerases I and II, respectively, and the Artemis and Metnase endonucleases, which can trim damaged overhangs of diverse structure. TDP1 as well as APE1 can remove 3'-phosphoglycolates and other 3' blocks, while CtIP appears to provide an alternative pathway for topoisomerase II fragment removal. Ku, a core DSB joining protein, can cleave abasic sites near DNA ends. The downstream processes of patching and ligation are tolerant of residual damage, and can sometimes proceed without complete damage removal. Despite these redundant pathways for resolution, damaged ends appear to be a significant barrier to rejoining, and their resolution may be a rate-limiting step in repair of some DSBs..
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Affiliation(s)
- Lawrence F Povirk
- Department of Pharmacology and Toxicology, and Massey Cancer Center, Virginia Commonwealth University, 401 College St. Richmond, VA 23298, USA, 804-828-9640
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Williamson EA, Damiani L, Leitao A, Hu C, Hathaway H, Oprea T, Sklar L, Shaheen M, Bauman J, Wang W, Nickoloff JA, Lee SH, Hromas R. Targeting the transposase domain of the DNA repair component Metnase to enhance chemotherapy. Cancer Res 2012; 72:6200-8. [PMID: 23090115 DOI: 10.1158/0008-5472.can-12-0313] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Previous studies have shown that the DNA repair component Metnase (SETMAR) mediates resistance to DNA damaging cancer chemotherapy. Metnase has a nuclease domain that shares homology with the Transposase family. We therefore virtually screened the tertiary Metnase structure against the 550,000 compound ChemDiv library to identify small molecules that might dock in the active site of the transposase nuclease domain of Metnase. We identified eight compounds as possible Metnase inhibitors. Interestingly, among these candidate inhibitors were quinolone antibiotics and HIV integrase inhibitors, which share common structural features. Previous reports have described possible activity of quinolones as antineoplastic agents. Therefore, we chose the quinolone ciprofloxacin for further study, based on its wide clinical availability and low toxicity. We found that ciprofloxacin inhibits the ability of Metnase to cleave DNA and inhibits Metnase-dependent DNA repair. Ciprofloxacin on its own did not induce DNA damage, but it did reduce repair of chemotherapy-induced DNA damage. Ciprofloxacin increased the sensitivity of cancer cell lines and a xenograft tumor model to clinically relevant chemotherapy. These studies provide a mechanism for the previously postulated antineoplastic activity of quinolones, and suggest that ciprofloxacin might be a simple yet effective adjunct to cancer chemotherapy.
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Affiliation(s)
- Elizabeth A Williamson
- Department of Medicine, University of Florida and Shands Health Care System, Gainesville, Florida, USA
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Transposable elements and human cancer: a causal relationship? Biochim Biophys Acta Rev Cancer 2012; 1835:28-35. [PMID: 22982062 DOI: 10.1016/j.bbcan.2012.09.001] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2012] [Revised: 08/30/2012] [Accepted: 09/04/2012] [Indexed: 12/18/2022]
Abstract
Transposable elements are present in almost all genomes including that of humans. These mobile DNA sequences are capable of invading genomes and their impact on genome evolution is substantial as they contribute to the genetic diversity of organisms. The mobility of transposable elements can cause deleterious mutations, gene disruption and chromosome rearrangements that may lead to several pathologies including cancer. This mini-review aims to give a brief overview of the relationship that transposons and retrotransposons may have in the genetic cause of human cancer onset, or conversely creating protection against cancer. Finally, the cause of TE mobility may also be the cancer cell environment itself.
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Chénais B, Caruso A, Hiard S, Casse N. The impact of transposable elements on eukaryotic genomes: from genome size increase to genetic adaptation to stressful environments. Gene 2012; 509:7-15. [PMID: 22921893 DOI: 10.1016/j.gene.2012.07.042] [Citation(s) in RCA: 195] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2012] [Revised: 07/16/2012] [Accepted: 07/25/2012] [Indexed: 11/25/2022]
Abstract
Transposable elements (TEs) are present in roughly all genomes. These mobile DNA sequences are able to invade genomes and their impact on genome evolution is substantial. The mobility of TEs can induce the appearance of deleterious mutations, gene disruption and chromosome rearrangements, but transposition activity also has positive aspects and the mutational activities of TEs contribute to the genetic diversity of organisms. This short review aims to give a brief overview of the impact TEs may have on animal and plant genome structure and expression, and the relationship between TEs and the stress response of organisms, including insecticide resistance.
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Affiliation(s)
- Benoît Chénais
- Université du Maine, EA2160 Mer Molécules Santé, UFR Sciences et Techniques, Avenue Olivier Messiaen, F-72085 Le Mans, France.
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Bailey AD, Gray LT, Pavelitz T, Newman JC, Horibata K, Tanaka K, Weiner AM. The conserved Cockayne syndrome B-piggyBac fusion protein (CSB-PGBD3) affects DNA repair and induces both interferon-like and innate antiviral responses in CSB-null cells. DNA Repair (Amst) 2012; 11:488-501. [PMID: 22483866 PMCID: PMC3340519 DOI: 10.1016/j.dnarep.2012.02.004] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2011] [Revised: 02/15/2012] [Accepted: 02/21/2012] [Indexed: 01/24/2023]
Abstract
Cockayne syndrome is a segmental progeria most often caused by mutations in the CSB gene encoding a SWI/SNF-like ATPase required for transcription-coupled DNA repair (TCR). Over 43Mya before marmosets diverged from humans, a piggyBac3 (PGBD3) transposable element integrated into intron 5 of the CSB gene. As a result, primate CSB genes now generate both CSB protein and a conserved CSB-PGBD3 fusion protein in which the first 5 exons of CSB are alternatively spliced to the PGBD3 transposase. Using a host cell reactivation assay, we show that the fusion protein inhibits TCR of oxidative damage but facilitates TCR of UV damage. We also show by microarray analysis that expression of the fusion protein alone in CSB-null UV-sensitive syndrome (UVSS) cells induces an interferon-like response that resembles both the innate antiviral response and the prolonged interferon response normally maintained by unphosphorylated STAT1 (U-STAT1); moreover, as might be expected based on conservation of the fusion protein, this potentially cytotoxic interferon-like response is largely reversed by coexpression of functional CSB protein. Interestingly, expression of CSB and the CSB-PGBD3 fusion protein together, but neither alone, upregulates the insulin growth factor binding protein IGFBP5 and downregulates IGFBP7, suggesting that the fusion protein may also confer a metabolic advantage, perhaps in the presence of DNA damage. Finally, we show that the fusion protein binds in vitro to members of a dispersed family of 900 internally deleted piggyBac elements known as MER85s, providing a potential mechanism by which the fusion protein could exert widespread effects on gene expression. Our data suggest that the CSB-PGBD3 fusion protein is important in both health and disease, and could play a role in Cockayne syndrome.
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Affiliation(s)
- Arnold D. Bailey
- Department of Biochemistry, School of Medicine, University of Washington, Seattle, WA 98195-7350, USA
| | - Lucas T. Gray
- Department of Biochemistry, School of Medicine, University of Washington, Seattle, WA 98195-7350, USA
| | - Thomas Pavelitz
- Department of Biochemistry, School of Medicine, University of Washington, Seattle, WA 98195-7350, USA
| | - John C. Newman
- Department of Internal Medicine, University of California, 505 Parnassus Avenue, San Francisco, CA 94122
| | - Katsuyoshi Horibata
- Laboratories of Organismal Biosystems, Graduate School of Frontier Biosciences, Osaka University, Osaka 565-0871, Japan
| | - Kiyoji Tanaka
- Laboratories of Organismal Biosystems, Graduate School of Frontier Biosciences, Osaka University, Osaka 565-0871, Japan
| | - Alan M. Weiner
- Department of Biochemistry, School of Medicine, University of Washington, Seattle, WA 98195-7350, USA
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Hromas R, Williamson EA, Fnu S, Lee YJ, Park SJ, Beck BD, You JS, Leitao A, Laitao A, Nickoloff JA, Lee SH. Chk1 phosphorylation of Metnase enhances DNA repair but inhibits replication fork restart. Oncogene 2012; 31:4245-54. [PMID: 22231448 DOI: 10.1038/onc.2011.586] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Chk1 both arrests replication forks and enhances repair of DNA damage by phosphorylating downstream effectors. Although there has been a concerted effort to identify effectors of Chk1 activity, underlying mechanisms of effector action are still being identified. Metnase (also called SETMAR) is a SET and transposase domain protein that promotes both DNA double-strand break (DSB) repair and restart of stalled replication forks. In this study, we show that Metnase is phosphorylated only on Ser495 (S495) in vivo in response to DNA damage by ionizing radiation. Chk1 is the major mediator of this phosphorylation event. We had previously shown that wild-type (wt) Metnase associates with chromatin near DSBs and methylates histone H3 Lys36. Here we show that a Ser495Ala (S495A) Metnase mutant, which is not phosphorylated by Chk1, is defective in DSB-induced chromatin association. The S495A mutant also fails to enhance repair of an induced DSB when compared with wt Metnase. Interestingly, the S495A mutant demonstrated increased restart of stalled replication forks compared with wt Metnase. Thus, phosphorylation of Metnase S495 differentiates between these two functions, enhancing DSB repair and repressing replication fork restart. In summary, these data lend insight into the mechanism by which Chk1 enhances repair of DNA damage while at the same time repressing stalled replication fork restart.
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Affiliation(s)
- R Hromas
- Department of Medicine, University of Florida and Shands Health Care System, Gainesville, FL 32610, USA.
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