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Taniai E, Yafune A, Nakajima M, Hayashi SM, Nakane F, Itahashi M, Shibutani M. Ochratoxin A induces karyomegaly and cell cycle aberrations in renal tubular cells without relation to induction of oxidative stress responses in rats. Toxicol Lett 2014; 224:64-72. [DOI: 10.1016/j.toxlet.2013.10.001] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2013] [Revised: 09/29/2013] [Accepted: 10/01/2013] [Indexed: 12/28/2022]
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52
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Brooks K, Chia KM, Spoerri L, Mukhopadhyay P, Wigan M, Stark M, Pavey S, Gabrielli B. Defective Decatenation Checkpoint Function Is a Common Feature of Melanoma. J Invest Dermatol 2014; 134:150-158. [DOI: 10.1038/jid.2013.264] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2012] [Revised: 04/17/2013] [Accepted: 04/30/2013] [Indexed: 12/16/2022]
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Li XM, Yu C, Wang ZW, Zhang YL, Liu XM, Zhou D, Sun QY, Fan HY. DNA topoisomerase II is dispensable for oocyte meiotic resumption but is essential for meiotic chromosome condensation and separation in mice. Biol Reprod 2013; 89:118. [PMID: 24048577 DOI: 10.1095/biolreprod.113.110692] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
During mitosis, DNA topoisomerase II (TOP2) is required for sister chromatid separation. When TOP2 activity is inhibited, a decatenation checkpoint is activated by entangled chromatin. However, the functions of TOP2 in oocyte meiosis, particularly for homologous chromosome segregation during meiosis I, have not been investigated. In addition, it remains unknown if TOP2 inhibition activates a decatenation checkpoint at the G2/M transition in oocytes. In this study, we used mouse oocytes and specific inhibitors of TOP2 (ICRF-193 and etoposide) to investigate the role of TOP2 in meiosis. Our results indicated that an effective decatenation checkpoint did not exist in fully grown oocytes, as oocytes underwent the G2/M transition and reinitiated meiosis even when TOP2 activity was inhibited. However, oocytes treated with ICRF-193 had severe defects in chromosome condensation and homologous chromosome separation. Furthermore, condensed chromosomes failed to maintain their normal configurations in matured oocytes that were treated with ICRF-193. However, sister chromatid separation and subsequent chromosome decondensation during the exit from meiosis were not blocked by TOP2 inhibitors. These results indicated that TOP2 had a specific, crucial function in meiosis I. Thus, we identified important functions of TOP2 during oocyte maturation and provided novel insights into the decatenation checkpoint during meiosis.
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Affiliation(s)
- Xiao-Meng Li
- Life Sciences Institute, Zhejiang University, Hangzhou, China
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Furniss KL, Tsai HJ, Byl JAW, Lane AB, Vas AC, Hsu WS, Osheroff N, Clarke DJ. Direct monitoring of the strand passage reaction of DNA topoisomerase II triggers checkpoint activation. PLoS Genet 2013; 9:e1003832. [PMID: 24098144 PMCID: PMC3789831 DOI: 10.1371/journal.pgen.1003832] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2011] [Accepted: 08/10/2013] [Indexed: 02/04/2023] Open
Abstract
By necessity, the ancient activity of type II topoisomerases co-evolved with the double-helical structure of DNA, at least in organisms with circular genomes. In humans, the strand passage reaction of DNA topoisomerase II (Topo II) is the target of several major classes of cancer drugs which both poison Topo II and activate cell cycle checkpoint controls. It is important to know the cellular effects of molecules that target Topo II, but the mechanisms of checkpoint activation that respond to Topo II dysfunction are not well understood. Here, we provide evidence that a checkpoint mechanism monitors the strand passage reaction of Topo II. In contrast, cells do not become checkpoint arrested in the presence of the aberrant DNA topologies, such as hyper-catenation, that arise in the absence of Topo II activity. An overall reduction in Topo II activity (i.e. slow strand passage cycles) does not activate the checkpoint, but specific defects in the T-segment transit step of the strand passage reaction do induce a cell cycle delay. Furthermore, the cell cycle delay depends on the divergent and catalytically inert C-terminal region of Topo II, indicating that transmission of a checkpoint signal may occur via the C-terminus. Other, well characterized, mitotic checkpoints detect DNA lesions or monitor unattached kinetochores; these defects arise via failures in a variety of cell processes. In contrast, we have described the first example of a distinct category of checkpoint mechanism that monitors the catalytic cycle of a single specific enzyme in order to determine when chromosome segregation can proceed faithfully.
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Affiliation(s)
- Katherine L. Furniss
- Department of Genetics, Cell Biology & Development, University of Minnesota, Minneapolis, Minnesota, United States of America
| | - Hung-Ji Tsai
- Department of Genetics, Cell Biology & Development, University of Minnesota, Minneapolis, Minnesota, United States of America
| | - Jo Ann W. Byl
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, Tennessee, United States of America
| | - Andrew B. Lane
- Department of Genetics, Cell Biology & Development, University of Minnesota, Minneapolis, Minnesota, United States of America
| | - Amit C. Vas
- Department of Genetics, Cell Biology & Development, University of Minnesota, Minneapolis, Minnesota, United States of America
| | - Wei-Shan Hsu
- Department of Genetics, Cell Biology & Development, University of Minnesota, Minneapolis, Minnesota, United States of America
| | - Neil Osheroff
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, Tennessee, United States of America
| | - Duncan J. Clarke
- Department of Genetics, Cell Biology & Development, University of Minnesota, Minneapolis, Minnesota, United States of America
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55
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Zhang YL, Yu C, Ji SY, Li XM, Zhang YP, Zhang D, Zhou D, Fan HY. TOP2β is essential for ovarian follicles that are hypersensitive to chemotherapeutic drugs. Mol Endocrinol 2013; 27:1678-91. [PMID: 24002654 DOI: 10.1210/me.2013-1108] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
The mechanisms underlying chemotherapy-induced acceleration of ovarian insufficiency are not fully understood, particularly for ovarian granulosa cells (GCs). We used two widely used cancer chemotherapeutic reagents, bleomycin and VP-16, and an in vivo GC-specific DNA topoisomerase II-β (TOP2β) (Top2b) knockout mouse model to investigate the effects of chemotherapy-induced DNA damage on growing mouse follicles. Bleomycin and VP-16 caused massive double-strand DNA breaks in the GCs of growing follicles in a time-dependent manner as shown by DNA-damage checkpoint activation. This damage was associated with apoptotic GC death and resulted in follicle atresia and ovulation failure. However, FSH-regulated ovarian functions, including estrogen biosynthesis and estrogen target gene expression, were not significantly affected by these genotoxins. TOP2β, a target of several chemotherapeutic drugs including VP-16, was abundantly expressed in the GCs of growing follicles. GC-specific deletion of Top2b using Cyp19-Cre caused DNA damage accumulations in these cells, follicle atresia, and decreased ovulation in response to exogenous gonadotropins. The ovaries of Top2b conditional knockout mice were also more sensitive to low-dose genotoxin treatment than wild-type mice ovaries. Thus, our results indicate that GCs are hypersensitive to genotoxic chemotherapeutic drugs and can activate the canonical DNA-damage checkpoint and the p53-dependent apoptotic pathway in response to insults that damage DNA. We also newly identified TOP2β as a factor involved in regulating GC genomic integrity and follicle atresia. This study has clinical implications for ovarian functional defects both for premenopausal cancer survivors and healthy women.
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Affiliation(s)
- Yin-Li Zhang
- Life Sciences Institute, Zhejiang University, 866 Yu Hang Tang Road, Hangzhou, China 310058.
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56
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Popuri V, Tadokoro T, Croteau DL, Bohr VA. Human RECQL5: guarding the crossroads of DNA replication and transcription and providing backup capability. Crit Rev Biochem Mol Biol 2013; 48:289-99. [PMID: 23627586 DOI: 10.3109/10409238.2013.792770] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
DNA helicases are ubiquitous enzymes that catalyze unwinding of duplex DNA and function in all metabolic processes in which access to single-stranded DNA is required, including DNA replication, repair, recombination and RNA transcription. RecQ helicases are a conserved family of DNA helicases that display highly specialized and vital roles in the maintenance of genome stability. Mutations in three of the five human RecQ helicases, BLM, WRN and RECQL4 are associated with the genetic disorders Bloom syndrome, Werner syndrome and Rothmund-Thomson syndrome that are characterized by chromosomal instability, premature aging and predisposition to cancer. The biological role of human RECQL5 is only partially understood and RECQL5 has not yet been associated with any human disease. Illegitimate recombination and replication stress are hallmarks of human cancers and common instigators for genomic instability and cell death. Recql5 knockout mice are cancer prone and show increased chromosomal instability. Recql5-deficient mouse embryonic fibroblasts are sensitive to camptothecin and display elevated levels of sister chromatid exchanges. Unlike other human RecQ helicases, RECQL5 is recruited to single-stranded DNA breaks and is also proposed to play an essential role in RNA transcription. Here, we review the established roles of RECQL5 at the cross roads of DNA replication, recombination and transcription, and propose that human RECQL5 provides important backup functions in the absence of other DNA helicases.
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Affiliation(s)
- Venkateswarlu Popuri
- Laboratory of Molecular Gerontology, National Institute on Aging, NIH, Baltimore, MD 21224, USA
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57
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Solhaug A, Holme JA, Haglund K, Dendele B, Sergent O, Pestka J, Lagadic-Gossmann D, Eriksen GS. Alternariol induces abnormal nuclear morphology and cell cycle arrest in murine RAW 264.7 macrophages. Toxicol Lett 2013; 219:8-17. [PMID: 23454835 DOI: 10.1016/j.toxlet.2013.02.012] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2012] [Revised: 02/14/2013] [Accepted: 02/19/2013] [Indexed: 12/18/2022]
Abstract
The mycotoxin alternariol (AOH), a frequent contaminant in fruit and cereal products, is known to induce DNA damage with subsequent cell cycle arrest. Here we elucidated the effects of AOH on stages of cell cycle progression using the RAW 264.7 macrophage model. AOH resulted in an accumulation of cells in the G2/M-phase (4N). Most cells exhibited a large G2 nucleus whereas numbers of true mitotic cells were reduced relative to control. Both cyclin B1 and p-cdc2 levels increased, while cyclin B1 remained in the cytoplasm; suggesting arrest in the G2/M transition point. Remarkably, after exposure to AOH for 24h, most of the cells exhibited abnormally shaped nuclei, as evidenced by partly divided nuclei, nuclear blebs, polyploidy and micronuclei (MN). AOH treatment also induced abnormal Aurora B bridges, suggesting that cytokinesis was interfered within cells undergoing karyokinesis. A minor part of the resultant G1 tetraploid (4N) cells re-entered the S-phase and progressed to 8N cells.
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Affiliation(s)
- A Solhaug
- Norwegian Veterinary Institute, Oslo, Norway.
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58
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Kim SO, Sakchaisri K, N. R. T, Soung NK, Jang JH, Kim YS, Lee KS, Kwon YT, Asami Y, Ahn JS, Erikson RL, Kim BY. STK295900, a dual inhibitor of topoisomerase 1 and 2, induces G(2) arrest in the absence of DNA damage. PLoS One 2013; 8:e53908. [PMID: 23349762 PMCID: PMC3551932 DOI: 10.1371/journal.pone.0053908] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2012] [Accepted: 12/04/2012] [Indexed: 11/18/2022] Open
Abstract
STK295900, a small synthetic molecule belonging to a class of symmetric bibenzimidazoles, exhibits antiproliferative activity against various human cancer cell lines from different origins. Examining the effect of STK295900 in HeLa cells indicates that it induces G(2) phase arrest without invoking DNA damage. Further analysis shows that STK295900 inhibits DNA relaxation that is mediated by topoisomerase 1 (Top 1) and topoisomerase 2 (Top 2) in vitro. In addition, STK295900 also exhibits protective effect against DNA damage induced by camptothecin. However, STK295900 does not affect etoposide-induced DNA damage. Moreover, STK295900 preferentially exerts cytotoxic effect on cancer cell lines while camptothecin, etoposide, and Hoechst 33342 affected both cancer and normal cells. Therefore, STK295900 has a potential to be developed as an anticancer chemotherapeutic agent.
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Affiliation(s)
- Sun-Ok Kim
- Korea Research Institute of Bioscience and Biotechnology (KRIBB), Ochang, Cheongwon, Korea
- Department of Biochemistry, College of Natural Sciences, ChungNam National University, Yuseonggu, Daejeon, Korea
| | - Krisada Sakchaisri
- Korea Research Institute of Bioscience and Biotechnology (KRIBB), Ochang, Cheongwon, Korea
| | - Thimmegowda N. R.
- Korea Research Institute of Bioscience and Biotechnology (KRIBB), Ochang, Cheongwon, Korea
| | - Nak Kyun Soung
- Korea Research Institute of Bioscience and Biotechnology (KRIBB), Ochang, Cheongwon, Korea
| | - Jae-Hyuk Jang
- Korea Research Institute of Bioscience and Biotechnology (KRIBB), Ochang, Cheongwon, Korea
| | - Young Sang Kim
- Department of Biochemistry, College of Natural Sciences, ChungNam National University, Yuseonggu, Daejeon, Korea
| | - Kyung Sang Lee
- Laboratory of Metabolism, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Yong Tae Kwon
- World Class University (WCU), Graduate School of Convergence Science and Technology and College of Medicine, Seoul National University, Seoul, Korea
- Center for Pharmacogenetics and Department of Pharmaceutical Sciences, School of Pharmacy, Universigy of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Yukihiro Asami
- Chemical Biology Department, RIKEN Advanced Science Institute, Wako-shi, Saitama, Japan
| | - Jong Seog Ahn
- Korea Research Institute of Bioscience and Biotechnology (KRIBB), Ochang, Cheongwon, Korea
| | - Raymond Leo Erikson
- Department of Molecular and Cellular Biology, Harvard University, Cambridge, Massachusetts, United States of America
| | - Bo Yeon Kim
- Korea Research Institute of Bioscience and Biotechnology (KRIBB), Ochang, Cheongwon, Korea
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Ray S, Panova T, Miller G, Volkov A, Porter ACG, Russell J, Panov KI, Zomerdijk JCBM. Topoisomerase IIα promotes activation of RNA polymerase I transcription by facilitating pre-initiation complex formation. Nat Commun 2013; 4:1598. [PMID: 23511463 PMCID: PMC3615473 DOI: 10.1038/ncomms2599] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2012] [Accepted: 02/09/2013] [Indexed: 11/15/2022] Open
Abstract
Type II DNA topoisomerases catalyse DNA double-strand cleavage, passage and re-ligation to effect topological changes. There is considerable interest in elucidating topoisomerase II roles, particularly as these proteins are targets for anti-cancer drugs. Here we uncover a role for topoisomerase IIα in RNA polymerase I-directed ribosomal RNA gene transcription, which drives cell growth and proliferation and is upregulated in cancer cells. Our data suggest that topoisomerase IIα is a component of the initiation-competent RNA polymerase Iβ complex and interacts directly with RNA polymerase I-associated transcription factor RRN3, which targets the polymerase to promoter-bound SL1 in pre-initiation complex formation. In cells, activation of rDNA transcription is reduced by inhibition or depletion of topoisomerase II, and this is accompanied by reduced transient double-strand DNA cleavage in the rDNA-promoter region and reduced pre-initiation complex formation. We propose that topoisomerase IIα functions in RNA polymerase I transcription to produce topological changes at the rDNA promoter that facilitate efficient de novo pre-initiation complex formation.
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Affiliation(s)
- Swagat Ray
- School of Biological Sciences and the Centre for Cancer Research and Cell Biology, Queen’s University Belfast, Belfast BT9 7BL, UK
| | - Tatiana Panova
- School of Biological Sciences and the Centre for Cancer Research and Cell Biology, Queen’s University Belfast, Belfast BT9 7BL, UK
- Centre for Gene Regulation and Expression, College of Life Sciences, University of Dundee, Dundee DD1 5EH, UK
| | - Gail Miller
- Centre for Gene Regulation and Expression, College of Life Sciences, University of Dundee, Dundee DD1 5EH, UK
| | - Arsen Volkov
- Gene Targeting Group, Centre for Haematology, Imperial College Faculty of Medicine, Du Cane Road, London W12 0NN, UK
| | - Andrew C. G. Porter
- Gene Targeting Group, Centre for Haematology, Imperial College Faculty of Medicine, Du Cane Road, London W12 0NN, UK
| | - Jackie Russell
- Centre for Gene Regulation and Expression, College of Life Sciences, University of Dundee, Dundee DD1 5EH, UK
| | - Konstantin I. Panov
- School of Biological Sciences and the Centre for Cancer Research and Cell Biology, Queen’s University Belfast, Belfast BT9 7BL, UK
- Centre for Gene Regulation and Expression, College of Life Sciences, University of Dundee, Dundee DD1 5EH, UK
- These authors contributed equally to this work
| | - Joost C. B. M. Zomerdijk
- Centre for Gene Regulation and Expression, College of Life Sciences, University of Dundee, Dundee DD1 5EH, UK
- These authors contributed equally to this work
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Pastor N, Domínguez I, Orta ML, Campanella C, Mateos S, Cortés F. The DNA topoisomerase II catalytic inhibitor merbarone is genotoxic and induces endoreduplication. Mutat Res 2012; 738-739:45-51. [PMID: 22921906 DOI: 10.1016/j.mrfmmm.2012.07.005] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2012] [Revised: 07/03/2012] [Accepted: 07/19/2012] [Indexed: 06/01/2023]
Abstract
In the last years a number of reports have shown that the so-called topoisomerase II (topo II) catalytic inhibitors are able to induce DNA and chromosome damage, an unexpected result taking into account that they do not stabilize topo II-DNA cleavable complexes, a feature of topo II poisons such as etoposide and amsacrine. Merbarone inhibits the catalytic activity of topo II by blocking DNA cleavage by the enzyme. While it was first reported that merbarone does not induce genotoxic effects in mammalian cells, this has been challenged by reports showing that the topo II inhibitor induces efficiently chromosome and DNA damage, and the question as to a possible behavior as a topo II poison has been put forward. Given these contradictory results, and the as yet incomplete knowledge of the molecular mechanism of action of merbarone, in the present study we have tried to further characterize the mechanism of action of merbarone on cell proliferation, cell cycle, as well as chromosome and DNA damage in cultured CHO cells. Merbarone was cytotoxic as well as genotoxic, inhibited topo II catalytic activity, and induced endoreduplication. We have also shown that merbarone-induced DNA damage depends upon ongoing DNA synthesis. Supporting this, inhibition of DNA synthesis causes reduction of DNA damage and increased cell survival.
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Affiliation(s)
- Nuria Pastor
- Department of Cell Biology, University of Seville, Spain
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61
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Tsuchiya T, Wang L, Yafune A, Kimura M, Ohishi T, Suzuki K, Mitsumori K, Shibutani M. Disruptive cell cycle regulation involving epigenetic downregulation of Cdkn2a (p16Ink4a) in early-stage liver tumor-promotion facilitating liver cell regeneration in rats. Toxicology 2012; 299:146-54. [DOI: 10.1016/j.tox.2012.05.018] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2012] [Revised: 05/14/2012] [Accepted: 05/21/2012] [Indexed: 11/29/2022]
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Gonzalez RE, Lim CU, Cole K, Bianchini CH, Schools GP, Davis BE, Wada I, Roninson IB, Broude EV. Effects of conditional depletion of topoisomerase II on cell cycle progression in mammalian cells. Cell Cycle 2012; 10:3505-14. [PMID: 22067657 DOI: 10.4161/cc.10.20.17778] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Topoisomerase II (Topo II) that decatenates newly synthesized DNA is targeted by many anticancer drugs. Some of these drugs stabilize intermediate complexes of DNA with Topo II and others act as catalytic inhibitors of Topo II. Simultaneous depletion of Topo IIα and Topo IIβ, the two isoforms of mammalian Topo II, prevents cell growth and normal mitosis, but the role of Topo II in other phases of mammalian cell cycle has not yet been elucidated. We have developed a derivative of p53-suppressed human cells with constitutive depletion of Topo IIβ and doxycycline-regulated conditional depletion of Topo IIα. The effects of Topo II depletion on cell cycle progression were analyzed by time-lapse video microscopy, pulse-chase flow cytometry and mitotic morphology. Topo II depletion increased the duration of the cell cycle and mitosis, interfered with chromosome condensation and sister chromatid segregation and led to frequent failure of cell division, ending in either cell death or restitution of polyploid cells. Topo II depletion did not change the rate of DNA replication but increased the duration of G 2. These results define the effects of decreased Topo II activity, rather than intermediate complex stabilization, on the mammalian cell cycle.
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63
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Taniai E, Hayashi H, Yafune A, Watanabe M, Akane H, Suzuki K, Mitsumori K, Shibutani M. Cellular distribution of cell cycle-related molecules in the renal tubules of rats treated with renal carcinogens for 28 days: relationship between cell cycle aberration and carcinogenesis. Arch Toxicol 2012; 86:1453-64. [DOI: 10.1007/s00204-012-0829-z] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2011] [Accepted: 02/27/2012] [Indexed: 01/08/2023]
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64
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Taniai E, Yafune A, Kimura M, Morita R, Nakane F, Suzuki K, Mitsumori K, Shibutani M. Fluctuations in cell proliferation, apoptosis, and cell cycle regulation at the early stage of tumor promotion in rat two-stage carcinogenesis models. J Toxicol Sci 2012. [DOI: 10.2131/jts.37.1113] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Affiliation(s)
- Eriko Taniai
- Laboratory of Veterinary Pathology, Tokyo University of Agriculture and Technology
- Pathogenetic Veterinary Science, United Graduate School of Veterinary Sciences, Gifu University
| | - Atsunori Yafune
- Laboratory of Veterinary Pathology, Tokyo University of Agriculture and Technology
- Pathogenetic Veterinary Science, United Graduate School of Veterinary Sciences, Gifu University
| | - Masayuki Kimura
- Laboratory of Veterinary Pathology, Tokyo University of Agriculture and Technology
| | - Reiko Morita
- Laboratory of Veterinary Pathology, Tokyo University of Agriculture and Technology
- Pathogenetic Veterinary Science, United Graduate School of Veterinary Sciences, Gifu University
| | - Fumiyuki Nakane
- Laboratory of Veterinary Pathology, Tokyo University of Agriculture and Technology
| | - Kazuhiko Suzuki
- Laboratory of Veterinary Pathology, Tokyo University of Agriculture and Technology
| | - Kunitoshi Mitsumori
- Laboratory of Veterinary Pathology, Tokyo University of Agriculture and Technology
| | - Makoto Shibutani
- Laboratory of Veterinary Pathology, Tokyo University of Agriculture and Technology
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65
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Taniai E, Yafune A, Hayashi H, Itahashi M, Hara-Kudo Y, Suzuki K, Mitsumori K, Shibutani M. Aberrant activation of ubiquitin D at G 2 phase and apoptosis by carcinogens that evoke cell proliferation after 28-day administration in rats. J Toxicol Sci 2012. [DOI: 10.2131/jts.37.1093] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Affiliation(s)
- Eriko Taniai
- Laboratory of Veterinary Pathology, Tokyo University of Agriculture and Technology
- Pathogenetic Veterinary Science, United Graduate School of Veterinary Sciences, Gifu University
| | - Atsunori Yafune
- Laboratory of Veterinary Pathology, Tokyo University of Agriculture and Technology
- Pathogenetic Veterinary Science, United Graduate School of Veterinary Sciences, Gifu University
- Gotemba Laboratory, Bozo Research Center Inc
| | - Hitomi Hayashi
- Laboratory of Veterinary Pathology, Tokyo University of Agriculture and Technology
- Pathogenetic Veterinary Science, United Graduate School of Veterinary Sciences, Gifu University
| | - Megu Itahashi
- Laboratory of Veterinary Pathology, Tokyo University of Agriculture and Technology
- Pathogenetic Veterinary Science, United Graduate School of Veterinary Sciences, Gifu University
| | | | - Kazuhiko Suzuki
- Laboratory of Veterinary Pathology, Tokyo University of Agriculture and Technology
| | - Kunitoshi Mitsumori
- Laboratory of Veterinary Pathology, Tokyo University of Agriculture and Technology
| | - Makoto Shibutani
- Laboratory of Veterinary Pathology, Tokyo University of Agriculture and Technology
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Sapetto-Rebow B, McLoughlin SC, O'Shea LC, O'Leary O, Willer JR, Alvarez Y, Collery R, O'Sullivan J, Van Eeden F, Hensey C, Kennedy BN. Maternal topoisomerase II alpha, not topoisomerase II beta, enables embryonic development of zebrafish top2a-/- mutants. BMC DEVELOPMENTAL BIOLOGY 2011; 11:71. [PMID: 22111588 PMCID: PMC3287258 DOI: 10.1186/1471-213x-11-71] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/23/2010] [Accepted: 11/23/2011] [Indexed: 11/10/2022]
Abstract
BACKGROUND Genetic alterations in human topoisomerase II alpha (TOP2A) are linked to cancer susceptibility. TOP2A decatenates chromosomes and thus is necessary for multiple aspects of cell division including DNA replication, chromosome condensation and segregation. Topoisomerase II alpha is also required for embryonic development in mammals, as mouse Top2a knockouts result in embryonic lethality as early as the 4-8 cell stage. The purpose of this study was to determine whether the extended developmental capability of zebrafish top2a mutants arises from maternal expression of top2a or compensation from its top2b paralogue. RESULTS Here, we describe bloody minded (blm), a novel mutant of zebrafish top2a. In contrast to mouse Top2a nulls, zebrafish top2a mutants survive to larval stages (4-5 day post fertilization). Developmental analyses demonstrate abundant expression of maternal top2a but not top2b. Inhibition or poisoning of maternal topoisomerase II delays embryonic development by extending the cell cycle M-phase. Zygotic top2a and top2b are co-expressed in the zebrafish CNS, but endogenous or ectopic top2b RNA appear unable to prevent the blm phenotype. CONCLUSIONS We conclude that maternal top2a enables zebrafish development before the mid-zygotic transition (MZT) and that zebrafish top2a and top2b are not functionally redundant during development after activation of the zygotic genome.
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Affiliation(s)
- Beata Sapetto-Rebow
- UCD School of Biomolecular and Biomedical Science, UCD Conway Institute, University College Dublin, Dublin, Ireland
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Hirsch ML, Fagan BM, Dumitru R, Bower JJ, Yadav S, Porteus MH, Pevny LH, Samulski RJ. Viral single-strand DNA induces p53-dependent apoptosis in human embryonic stem cells. PLoS One 2011; 6:e27520. [PMID: 22114676 PMCID: PMC3219675 DOI: 10.1371/journal.pone.0027520] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2011] [Accepted: 10/18/2011] [Indexed: 11/19/2022] Open
Abstract
Human embryonic stem cells (hESCs) are primed for rapid apoptosis following mild forms of genotoxic stress. A natural form of such cellular stress occurs in response to recombinant adeno-associated virus (rAAV) single-strand DNA genomes, which exploit the host DNA damage response for replication and genome persistence. Herein, we discovered a unique DNA damage response induced by rAAV transduction specific to pluripotent hESCs. Within hours following rAAV transduction, host DNA damage signaling was elicited as measured by increased gamma-H2AX, ser15-p53 phosphorylation, and subsequent p53-dependent transcriptional activation. Nucleotide incorporation assays demonstrated that rAAV transduced cells accumulated in early S-phase followed by the induction of apoptosis. This lethal signaling sequalae required p53 in a manner independent of transcriptional induction of Puma, Bax and Bcl-2 and was not evident in cells differentiated towards a neural lineage. Consistent with a lethal DNA damage response induced upon rAAV transduction of hESCs, empty AAV protein capsids demonstrated no toxicity. In contrast, DNA microinjections demonstrated that the minimal AAV origin of replication and, in particular, a 40 nucleotide G-rich tetrad repeat sequence, was sufficient for hESC apoptosis. Our data support a model in which rAAV transduction of hESCs induces a p53-dependent lethal response that is elicited by a telomeric sequence within the AAV origin of replication.
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Affiliation(s)
- Matthew L. Hirsch
- Gene Therapy Center, University of North Carolina, Chapel Hill, North Carolina, United States of America
- * E-mail: (MLH); (RJS)
| | - B. Matthew Fagan
- Human Embryonic Stem Cell Core Facility, University of North Carolina, Chapel Hill, North Carolina, United States of America
| | - Raluca Dumitru
- Department of Cell and Developmental Biology, Neuroscience Center, University of North Carolina, Chapel Hill, North Carolina, United States of America
| | - Jacquelyn J. Bower
- Department of Pathology and Laboratory Medicine, University of North Carolina, Chapel Hill, North Carolina, United States of America
| | - Swati Yadav
- Gene Therapy Center, University of North Carolina, Chapel Hill, North Carolina, United States of America
| | - Matthew H. Porteus
- Department of Pediatrics-Cancer Biology, Stanford University, Palo Alto, California, United States of America
| | - Larysa H. Pevny
- Department of Genetics, University of North Carolina, Chapel Hill, North Carolina, United States of America
- Department of Cell and Developmental Biology, Neuroscience Center, University of North Carolina, Chapel Hill, North Carolina, United States of America
| | - R. Jude Samulski
- Gene Therapy Center, University of North Carolina, Chapel Hill, North Carolina, United States of America
- Department of Pharmacology, University of North Carolina, Chapel Hill, North Carolina, United States of America
- * E-mail: (MLH); (RJS)
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Ramamoorthy M, Tadokoro T, Rybanska I, Ghosh AK, Wersto R, May A, Kulikowicz T, Sykora P, Croteau DL, Bohr VA. RECQL5 cooperates with Topoisomerase II alpha in DNA decatenation and cell cycle progression. Nucleic Acids Res 2011; 40:1621-35. [PMID: 22013166 PMCID: PMC3287182 DOI: 10.1093/nar/gkr844] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
DNA decatenation mediated by Topoisomerase II is required to separate the interlinked sister chromatids post-replication. SGS1, a yeast homolog of the human RecQ family of helicases interacts with Topoisomerase II and plays a role in chromosome segregation, but this functional interaction has yet to be identified in higher organisms. Here, we report a physical and functional interaction of Topoisomerase IIα with RECQL5, one of five mammalian RecQ helicases, during DNA replication. Direct interaction of RECQL5 with Topoisomerase IIα stimulates the decatenation activity of Topoisomerase IIα. Consistent with these observations, RECQL5 co-localizes with Topoisomerase IIα during S-phase of the cell cycle. Moreover, cells with stable depletions of RECQL5 display a slow proliferation rate, a G2/M cell cycle arrest and late S-phase cycling defects. Metaphase spreads generated from RECQL5-depleted cells exhibit undercondensed and entangled chromosomes. Further, RECQL5-depleted cells activate a G2/M checkpoint and undergo apoptosis. These phenotypes are similar to those observed when Topoisomerase II catalytic activity is inhibited. These results reveal an important role for RECQL5 in the maintenance of genomic stability and a new insight into the decatenation process.
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Affiliation(s)
- Mahesh Ramamoorthy
- Laboratory of Molecular Gerontology, Biomedical Research Center, 251 Bayview Boulevard, National Institute on Aging, NIH, Baltimore, MD 21224, USA
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69
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Harvard C, Strong E, Mercier E, Colnaghi R, Alcantara D, Chow E, Martell S, Tyson C, Hrynchak M, McGillivray B, Hamilton S, Marles S, Mhanni A, Dawson AJ, Pavlidis P, Qiao Y, Holden JJ, Lewis SME, O'Driscoll M, Rajcan-Separovic E. Understanding the impact of 1q21.1 copy number variant. Orphanet J Rare Dis 2011; 6:54. [PMID: 21824431 PMCID: PMC3180300 DOI: 10.1186/1750-1172-6-54] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2011] [Accepted: 08/08/2011] [Indexed: 01/10/2023] Open
Abstract
Background 1q21.1 Copy Number Variant (CNV) is associated with a highly variable phenotype ranging from congenital anomalies, learning deficits/intellectual disability (ID), to a normal phenotype. Hence, the clinical significance of this CNV can be difficult to evaluate. Here we described the consequences of the 1q21.1 CNV on genome-wide gene expression and function of selected candidate genes within 1q21.1 using cell lines from clinically well described subjects. Methods and Results Eight subjects from 3 families were included in the study: six with a 1q21.1 deletion and two with a 1q21.1 duplication. High resolution Affymetrix 2.7M array was used to refine the 1q21.1 CNV breakpoints and exclude the presence of secondary CNVs of pathogenic relevance. Whole genome expression profiling, studied in lymphoblast cell lines (LBCs) from 5 subjects, showed enrichment of genes from 1q21.1 in the top 100 genes ranked based on correlation of expression with 1q21.1 copy number. The function of two top genes from 1q21.1, CHD1L/ALC1 and PRKAB2, was studied in detail in LBCs from a deletion and a duplication carrier. CHD1L/ALC1 is an enzyme with a role in chromatin modification and DNA damage response while PRKAB2 is a member of the AMP kinase complex, which senses and maintains systemic and cellular energy balance. The protein levels for CHD1L/ALC1 and PRKAB2 were changed in concordance with their copy number in both LBCs. A defect in chromatin remodeling was documented based on impaired decatenation (chromatid untangling) checkpoint (DCC) in both LBCs. This defect, reproduced by CHD1L/ALC1 siRNA, identifies a new role of CHD1L/ALC1 in DCC. Both LBCs also showed elevated levels of micronuclei following treatment with a Topoisomerase II inhibitor suggesting increased DNA breaks. AMP kinase function, specifically in the deletion containing LBCs, was attenuated. Conclusion Our studies are unique as they show for the first time that the 1q21.1 CNV not only causes changes in the expression of its key integral genes, associated with changes at the protein level, but also results in changes in their known function, in the case of AMPK, and newly identified function such as DCC activation in the case of CHD1L/ALC1. Our results support the use of patient lymphoblasts for dissecting the functional sequelae of genes integral to CNVs in carrier cell lines, ultimately enhancing understanding of biological processes which may contribute to the clinical phenotype.
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Affiliation(s)
- Chansonette Harvard
- Child and Family Research Institute, Molecular Cytogenetics and Array Laboratory, 950 West 28th Avenue, Vancouver, BC, Canada
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