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Caldecott KW. Causes and consequences of DNA single-strand breaks. Trends Biochem Sci 2024; 49:68-78. [PMID: 38040599 DOI: 10.1016/j.tibs.2023.11.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2023] [Revised: 10/20/2023] [Accepted: 11/03/2023] [Indexed: 12/03/2023]
Abstract
DNA single-strand breaks (SSBs) are among the most common lesions arising in human cells, with tens to hundreds of thousands arising in each cell, each day. Cells have efficient mechanisms for the sensing and repair of these ubiquitous DNA lesions, but the failure of these processes to rapidly remove SSBs can lead to a variety of pathogenic outcomes. The threat posed by unrepaired SSBs is illustrated by the existence of at least six genetic diseases in which SSB repair (SSBR) is defective, all of which are characterised by neurodevelopmental and/or neurodegenerative pathology. Here, I review current understanding of how SSBs arise and impact on critical molecular processes, such as DNA replication and gene transcription, and their links to human disease.
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Affiliation(s)
- Keith W Caldecott
- Genome Damage and Stability Centre, School of Life Sciences, University of Sussex, Falmer, Brighton, UK.
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2
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Inai Y, Izawa T, Kamei T, Fujiwara S, Tanaka M, Yamate J, Kuwamura M. Difference in the Mechanism of Iron Overload-Enhanced Acute Hepatotoxicity Induced by Thioacetamide and Carbon Tetrachloride in Rats. Toxicol Pathol 2024; 52:55-66. [PMID: 38528719 DOI: 10.1177/01926233241235623] [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: 03/27/2024]
Abstract
Iron overload has been recognized as a risk factor for liver disease; however, little is known about its pathological role in the modification of liver injury. The purpose of this study is to investigate the influence of iron overload on liver injury induced by two hepatotoxicants with different pathogenesis in rats. Rats were fed a control (Cont), 0.8% high-iron (0.8% Fe), or 1% high-iron diet (1% Fe) for 4 weeks and were then administered with saline, thioacetamide (TAA), or carbon tetrachloride (CCl4). Hepatic and systemic iron overload were seen in the 0.8% and 1% Fe groups. Twenty-four hours after administration, hepatocellular necrosis induced by TAA and hepatocellular necrosis, degeneration, and vacuolation induced by CCl4, as well as serum transaminase values, were exacerbated in the 0.8% and 1% Fe groups compared to the Cont group. On the other hand, microvesicular vacuolation induced by CCl4 was decreased in 0.8% and 1% Fe groups. Hepatocellular DNA damage was increased by iron overload in both models, whereas a synergistic effect of oxidative stress by excess iron and hepatotoxicant was only present in the CCl4 model. The data showed that dietary iron overload exacerbates TAA- and CCl4-induced acute liver injury with different mechanisms.
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Affiliation(s)
- Yohei Inai
- Laboratory of Veterinary Pathology, Osaka Metropolitan University, Osaka, Japan
| | - Takeshi Izawa
- Laboratory of Veterinary Pathology, Osaka Metropolitan University, Osaka, Japan
| | - Tomomi Kamei
- Laboratory of Veterinary Pathology, Osaka Metropolitan University, Osaka, Japan
| | - Sho Fujiwara
- Laboratory of Veterinary Pathology, Osaka Metropolitan University, Osaka, Japan
| | - Miyuu Tanaka
- Laboratory of Veterinary Pathology, Osaka Metropolitan University, Osaka, Japan
| | - Jyoji Yamate
- Laboratory of Veterinary Pathology, Osaka Metropolitan University, Osaka, Japan
| | - Mitsuru Kuwamura
- Laboratory of Veterinary Pathology, Osaka Metropolitan University, Osaka, Japan
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3
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Sallmyr A, Bhandari SK, Naila T, Tomkinson AE. Mammalian DNA ligases; roles in maintaining genome integrity. J Mol Biol 2024; 436:168276. [PMID: 37714297 PMCID: PMC10843057 DOI: 10.1016/j.jmb.2023.168276] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2023] [Revised: 09/07/2023] [Accepted: 09/08/2023] [Indexed: 09/17/2023]
Abstract
The joining of breaks in the DNA phosphodiester backbone is essential for genome integrity. Breaks are generated during normal processes such as DNA replication, cytosine demethylation during differentiation, gene rearrangement in the immune system and germ cell development. In addition, they are generated either directly by a DNA damaging agent or indirectly due to damage excision during repair. Breaks are joined by a DNA ligase that catalyzes phosphodiester bond formation at DNA nicks with 3' hydroxyl and 5' phosphate termini. Three human genes encode ATP-dependent DNA ligases. These enzymes have a conserved catalytic core consisting of three subdomains that encircle nicked duplex DNA during ligation. The DNA ligases are targeted to different nuclear DNA transactions by specific protein-protein interactions. Both DNA ligase IIIα and DNA ligase IV form stable complexes with DNA repair proteins, XRCC1 and XRCC4, respectively. There is functional redundancy between DNA ligase I and DNA ligase IIIα in DNA replication, excision repair and single-strand break repair. Although DNA ligase IV is a core component of the major double-strand break repair pathway, non-homologous end joining, the other enzymes participate in minor, alternative double-strand break repair pathways. In contrast to the nucleus, only DNA ligase IIIα is present in mitochondria and is essential for maintaining the mitochondrial genome. Human immunodeficiency syndromes caused by mutations in either LIG1 or LIG4 have been described. Preclinical studies with DNA ligase inhibitors have identified potentially targetable abnormalities in cancer cells and evidence that DNA ligases are potential targets for cancer therapy.
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Affiliation(s)
- Annahita Sallmyr
- University of New Mexico Comprehensive Cancer Center and the Departments of Internal Medicine, and Molecular Genetics & Microbiology, University of New Mexico Health Sciences Center, United States
| | - Seema Khattri Bhandari
- University of New Mexico Comprehensive Cancer Center and the Departments of Internal Medicine, and Molecular Genetics & Microbiology, University of New Mexico Health Sciences Center, United States
| | - Tasmin Naila
- University of New Mexico Comprehensive Cancer Center and the Departments of Internal Medicine, and Molecular Genetics & Microbiology, University of New Mexico Health Sciences Center, United States
| | - Alan E Tomkinson
- University of New Mexico Comprehensive Cancer Center and the Departments of Internal Medicine, and Molecular Genetics & Microbiology, University of New Mexico Health Sciences Center, United States.
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4
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Ramos L, Truong S, Zhai B, Joshi J, Ghaidi F, Lizardo MM, Shyp T, Kung SH, Rezakhanlou AM, Oo HZ, Adomat H, Le Bihan S, Collins C, Bacha J, Brown D, Langlands J, Shen W, Lallous N, Sorensen PH, Daugaard M. A Bifunctional PARP-HDAC Inhibitor with Activity in Ewing Sarcoma. Clin Cancer Res 2023; 29:3541-3553. [PMID: 37279093 PMCID: PMC10472104 DOI: 10.1158/1078-0432.ccr-22-3897] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2022] [Revised: 04/20/2023] [Accepted: 06/02/2023] [Indexed: 06/08/2023]
Abstract
PURPOSE Histone deacetylase (HDAC) inhibition has been shown to induce pharmacologic "BRCAness" in cancer cells with proficient DNA repair activity. This provides a rationale for exploring combination treatments with HDAC and PARP inhibition in cancer types that are insensitive to single-agent PARP inhibitors (PARPi). Here, we report the concept and characterization of a novel bifunctional PARPi (kt-3283) with dual activity toward PARP1/2 and HDAC enzymes in Ewing sarcoma cells. EXPERIMENTAL DESIGN Inhibition of PARP1/2 and HDAC was measured using PARP1/2, HDAC activity, and PAR formation assays. Cytotoxicity was assessed by IncuCyte live cell imaging, CellTiter-Glo, and spheroid assays. Cell-cycle profiles were determined using propidium iodide staining and flow cytometry. DNA damage was examined by γH2AX expression and comet assay. Inhibition of metastatic potential by kt-3283 was evaluated via ex vivo pulmonary metastasis assay (PuMA). RESULTS Compared with FDA-approved PARP (olaparib) and HDAC (vorinostat) inhibitors, kt-3283 displayed enhanced cytotoxicity in Ewing sarcoma models. The kt-3283-induced cytotoxicity was associated with strong S and G2-M cell-cycle arrest in nanomolar concentration range and elevated DNA damage as assessed by γH2AX tracking and comet assays. In three-dimensional spheroid models of Ewing sarcoma, kt-3283 showed efficacy in lower concentrations than olaparib and vorinostat, and kt-3283 inhibited colonization of Ewing sarcoma cells in the ex vivo PuMA model. CONCLUSIONS Our data demonstrate the preclinical justification for studying the benefit of dual PARP and HDAC inhibition in the treatment of Ewing sarcoma in a clinical trial and provides proof-of-concept for a bifunctional single-molecule therapeutic strategy.
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Affiliation(s)
- Louise Ramos
- Department of Urologic Sciences, University of British Columbia, Vancouver, British Columbia, Canada
- Vancouver Prostate Centre, Vancouver, British Columbia, Canada
- Rakovina Therapeutics, Vancouver, British Columbia, Canada
| | - Sarah Truong
- Vancouver Prostate Centre, Vancouver, British Columbia, Canada
- Rakovina Therapeutics, Vancouver, British Columbia, Canada
| | - Beibei Zhai
- Department of Urologic Sciences, University of British Columbia, Vancouver, British Columbia, Canada
- Vancouver Prostate Centre, Vancouver, British Columbia, Canada
- Rakovina Therapeutics, Vancouver, British Columbia, Canada
| | - Jay Joshi
- Vancouver Prostate Centre, Vancouver, British Columbia, Canada
- Rakovina Therapeutics, Vancouver, British Columbia, Canada
| | - Fariba Ghaidi
- Vancouver Prostate Centre, Vancouver, British Columbia, Canada
- Rakovina Therapeutics, Vancouver, British Columbia, Canada
| | | | - Taras Shyp
- BC Cancer Agency, Vancouver, British Columbia, Canada
- Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, Canada
| | - Sonia H.Y. Kung
- Vancouver Prostate Centre, Vancouver, British Columbia, Canada
| | | | - Htoo Zarni Oo
- Vancouver Prostate Centre, Vancouver, British Columbia, Canada
| | - Hans Adomat
- Vancouver Prostate Centre, Vancouver, British Columbia, Canada
| | | | - Colin Collins
- Department of Urologic Sciences, University of British Columbia, Vancouver, British Columbia, Canada
- Vancouver Prostate Centre, Vancouver, British Columbia, Canada
| | - Jeffrey Bacha
- Rakovina Therapeutics, Vancouver, British Columbia, Canada
| | - Dennis Brown
- Rakovina Therapeutics, Vancouver, British Columbia, Canada
| | - John Langlands
- Rakovina Therapeutics, Vancouver, British Columbia, Canada
| | - Wang Shen
- Rakovina Therapeutics, Vancouver, British Columbia, Canada
| | - Nada Lallous
- Department of Urologic Sciences, University of British Columbia, Vancouver, British Columbia, Canada
- Vancouver Prostate Centre, Vancouver, British Columbia, Canada
| | - Poul H. Sorensen
- BC Cancer Agency, Vancouver, British Columbia, Canada
- Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, Canada
| | - Mads Daugaard
- Department of Urologic Sciences, University of British Columbia, Vancouver, British Columbia, Canada
- Vancouver Prostate Centre, Vancouver, British Columbia, Canada
- Rakovina Therapeutics, Vancouver, British Columbia, Canada
- Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, Canada
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Napoletani G, Soldan SS, Kannan T, Preston-Alp S, Vogel P, Maestri D, Caruso LB, Kossenkov A, Sobotka A, Lieberman PM, Tempera I. PARP1 Inhibition Halts EBV+ Lymphoma Progression by Disrupting the EBNA2/MYC Axis. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.07.05.547847. [PMID: 37461649 PMCID: PMC10350008 DOI: 10.1101/2023.07.05.547847] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 07/25/2023]
Abstract
PARP1 has been shown to regulate EBV latency. However, the therapeutic effect of PARP1 inhibitors on EBV+ lymphomagenesis has not yet been explored. Here, we show that PARPi BMN-673 has a potent anti-tumor effect on EBV-driven LCL in a mouse xenograft model. We found that PARP1 inhibition induces a dramatic transcriptional reprogramming of LCLs driven largely by the reduction of the MYC oncogene expression and dysregulation of MYC targets, both in vivo and in vitro. PARP1 inhibition also reduced the expression of viral oncoprotein EBNA2, which we previously demonstrated depends on PARP1 for activation of MYC. Further, we show that PARP1 inhibition blocks the chromatin association of MYC, EBNA2, and tumor suppressor p53. Overall, our study strengthens the central role of PARP1 in EBV malignant transformation and identifies the EBNA2/MYC pathway as a target of PARP1 inhibitors and its utility for the treatment of EBNA2-driven EBV-associated cancers.
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Affiliation(s)
| | | | | | | | - Peter Vogel
- Department of Comparative Pathology, St. Jude Children’s Research Hospital, Memphis, TN, USA
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Imamura R, Saito M, Shimada M, Kobayashi J, Ishiai M, Matsumoto Y. APTX acts in DNA double-strand break repair in a manner distinct from XRCC4. JOURNAL OF RADIATION RESEARCH 2023; 64:485-495. [PMID: 36940705 DOI: 10.1093/jrr/rrad007] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/11/2022] [Revised: 01/03/2023] [Indexed: 05/27/2023]
Abstract
Aprataxin (APTX), the product of the causative gene for hereditary neurogenerative syndromes Ataxia-oculomotor apraxia 1 and early onset ataxia with oculomotor apraxia and hypoalbuminemia, has an enzymatic activity of removing adenosine monophosphate from DNA 5'-end, which arises from abortive ligation by DNA ligases. It is also reported that APTX physically binds to XRCC1 and XRCC4, suggesting its involvement in DNA single-strand break repair (SSBR) and DNA double-strand break repair (DSBR) via non-homologous end joining pathway. Although the involvement of APTX in SSBR in association with XRCC1 has been established, the significance of APTX in DSBR and its interaction with XRCC4 have remained unclear. Here, we generated APTX knock-out (APTX-/-) cell from human osteosarcoma U2OS through CRISPR/Cas9-mediated genome editing system. APTX-/- cells exhibited increased sensitivity toward ionizing radiation (IR) and Camptothecin in association with retarded DSBR, as shown by increased number of retained γH2AX foci. However, the number of retained 53BP1 foci in APTX-/- cell was not discernibly different from wild-type cells, in stark contrast to XRCC4-depleted cells. The recruitment of GFP-tagged APTX (GFP-APTX) to the DNA damage sites was examined by laser micro-irradiation and live-cell imaging analysis using confocal microscope. The accumulation of GFP-APTX on the laser track was attenuated by siRNA-mediated depletion of XRCC1, but not XRCC4. Moreover, the deprivation of APTX and XRCC4 displayed additive inhibitory effects on DSBR after IR exposure and end joining of GFP reporter. These findings collectively suggest that APTX acts in DSBR in a manner distinct from XRCC4.
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Affiliation(s)
- Rikiya Imamura
- Laboratory for Zero-Carbon Energy, Institute of Innovative Research, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro-ku, Tokyo 152-8550, Japan
- National Cancer Center Research Institute, 5-1-1 Tsukiji, Chuo-ku, Tokyo 104-0045, Japan
| | - Mizuki Saito
- Laboratory for Zero-Carbon Energy, Institute of Innovative Research, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro-ku, Tokyo 152-8550, Japan
| | - Mikio Shimada
- Laboratory for Zero-Carbon Energy, Institute of Innovative Research, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro-ku, Tokyo 152-8550, Japan
| | - Junya Kobayashi
- Department of Radiological Sciences, School of Health Science at Narita, International University of Health and Welfare, 4-3 Kozunomori, Narita, Chiba 286-8686, Japan
| | - Masamichi Ishiai
- National Cancer Center Research Institute, 5-1-1 Tsukiji, Chuo-ku, Tokyo 104-0045, Japan
| | - Yoshihisa Matsumoto
- Laboratory for Zero-Carbon Energy, Institute of Innovative Research, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro-ku, Tokyo 152-8550, Japan
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7
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Prokurotaite E, Condorelli M, Dechene J, Bouziotis J, Lambertini M, Demeestere I. Impact of Breast Cancer and Germline BRCA Pathogenic Variants on Fertility Preservation in Young Women. Life (Basel) 2023; 13:life13040930. [PMID: 37109459 PMCID: PMC10146760 DOI: 10.3390/life13040930] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2023] [Revised: 03/24/2023] [Accepted: 03/30/2023] [Indexed: 04/05/2023] Open
Abstract
Background: Several studies have suggested that breast cancer (BC) and germline BRCA pathogenic variants (gBRCA PVs) could have a deleterious impact on ovarian reserve. Nevertheless, data are limited and mixed. Our objective was to evaluate the performance of fertility preservation (FP) in terms of the number of collected mature oocytes after ovarian stimulation (OS) in young women carrying a gBRCA PV, associated or not with BC. Methods: We conducted a retrospective monocentric study at HUB-Hôpital Erasme in Brussels. All women aged between 18 and 41 years diagnosed with invasive non-metastatic BC and/or gBRCA PV carriers who underwent OS for FP or preimplantation genetic testing for monogenic disorder (PGT-M) between November 2012 and October 2021 were included. Three groups were compared: BC patients without a gBRCA PV, BC patients with a gBRCA PV, and healthy gBRCA PV carriers. Ovarian reserve was evaluated based on the efficacy of OS and AMH levels. Results: A total of 85 patients underwent 100 cycles. The mean age (32.2 ± 3.9 years; p = 0.61) and median AMH level (1.9 [0.2–13] μg/L; p = 0.22) were similar between groups. Correlations between the number of mature oocytes and AMH level (p < 0.001) and between AMH and age (p < 0.001) were observed. No differences in the number of retrieved mature oocytes were observed between groups (p = 0.41), or for other OS parameters. Conclusion: Neither BC nor a gBRCA PV significantly affects ovarian reserve and FP efficacy in terms of the number of mature oocytes retrieved.
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Affiliation(s)
- Elze Prokurotaite
- Fertility Clinic, Department of Obstetrics and Gynecology, H.U.B—Hôpital Erasme, Université Libre de Bruxelles, 1070 Brussels, Belgium
| | - Margherita Condorelli
- Fertility Clinic, Department of Obstetrics and Gynecology, H.U.B—Hôpital Erasme, Université Libre de Bruxelles, 1070 Brussels, Belgium
- Research Laboratory on Human Reproduction, Université Libre de Bruxelles, 1070 Brussels, Belgium
| | - Julie Dechene
- Research Laboratory on Human Reproduction, Université Libre de Bruxelles, 1070 Brussels, Belgium
| | - Jason Bouziotis
- Department of Biomedical Research, H.U.B—Hôpital Erasme, Université Libre de Bruxelles, 1070 Brussels, Belgium
| | - Matteo Lambertini
- Department of Internal Medicine and Medical Specialties (DiMI), School of Medicine, University of Genova, 16132 Genova, Italy
- Department of Medical Oncology, U.O. Clinica di Oncologia Medica, IRCCS Ospedale Policlinico San Martino, 16132 Genova, Italy
| | - Isabelle Demeestere
- Fertility Clinic, Department of Obstetrics and Gynecology, H.U.B—Hôpital Erasme, Université Libre de Bruxelles, 1070 Brussels, Belgium
- Research Laboratory on Human Reproduction, Université Libre de Bruxelles, 1070 Brussels, Belgium
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8
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Garaycoechea JI, Quinlan C, Luijsterburg MS. Pathological consequences of DNA damage in the kidney. Nat Rev Nephrol 2023; 19:229-243. [PMID: 36702905 DOI: 10.1038/s41581-022-00671-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/09/2022] [Indexed: 01/27/2023]
Abstract
DNA lesions that evade repair can lead to mutations that drive the development of cancer, and cellular responses to DNA damage can trigger senescence and cell death, which are associated with ageing. In the kidney, DNA damage has been implicated in both acute and chronic kidney injury, and in renal cell carcinoma. The susceptibility of the kidney to chemotherapeutic agents that damage DNA is well established, but an unexpected link between kidney ciliopathies and the DNA damage response has also been reported. In addition, human genetic deficiencies in DNA repair have highlighted DNA crosslinks, DNA breaks and transcription-blocking damage as lesions that are particularly toxic to the kidney. Genetic tools in mice, as well as advances in kidney organoid and single-cell RNA sequencing technologies, have provided important insights into how specific kidney cell types respond to DNA damage. The emerging view is that in the kidney, DNA damage affects the local microenvironment by triggering a damage response and cell proliferation to replenish injured cells, as well as inducing systemic responses aimed at reducing exposure to genotoxic stress. The pathological consequences of DNA damage are therefore key to the nephrotoxicity of DNA-damaging agents and the kidney phenotypes observed in human DNA repair-deficiency disorders.
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Affiliation(s)
- Juan I Garaycoechea
- Hubrecht Institute-KNAW, University Medical Center Utrecht, Utrecht, The Netherlands.
| | - Catherine Quinlan
- Department of Paediatrics, University of Melbourne, Parkville, Australia
- Department of Nephrology, Royal Children's Hospital, Melbourne, Australia
- Department of Kidney Regeneration, Murdoch Children's Research Institute, Melbourne, Australia
| | - Martijn S Luijsterburg
- Department of Human Genetics, Leiden University Medical Center (LUMC), Leiden, The Netherlands.
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9
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Measuring DNA modifications with the comet assay: a compendium of protocols. Nat Protoc 2023; 18:929-989. [PMID: 36707722 DOI: 10.1038/s41596-022-00754-y] [Citation(s) in RCA: 83] [Impact Index Per Article: 83.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2021] [Accepted: 07/05/2022] [Indexed: 01/28/2023]
Abstract
The comet assay is a versatile method to detect nuclear DNA damage in individual eukaryotic cells, from yeast to human. The types of damage detected encompass DNA strand breaks and alkali-labile sites (e.g., apurinic/apyrimidinic sites), alkylated and oxidized nucleobases, DNA-DNA crosslinks, UV-induced cyclobutane pyrimidine dimers and some chemically induced DNA adducts. Depending on the specimen type, there are important modifications to the comet assay protocol to avoid the formation of additional DNA damage during the processing of samples and to ensure sufficient sensitivity to detect differences in damage levels between sample groups. Various applications of the comet assay have been validated by research groups in academia, industry and regulatory agencies, and its strengths are highlighted by the adoption of the comet assay as an in vivo test for genotoxicity in animal organs by the Organisation for Economic Co-operation and Development. The present document includes a series of consensus protocols that describe the application of the comet assay to a wide variety of cell types, species and types of DNA damage, thereby demonstrating its versatility.
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10
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He HL, Lai HY, Chan TC, Hsing CH, Huang SK, Hsieh KL, Chen TJ, Li WS, Kuo YH, Shiue YL, Li CF. Low expression of ZSCAN4 predicts unfavorable outcome in urothelial carcinoma of upper urinary tract and urinary bladder. World J Surg Oncol 2023; 21:62. [PMID: 36841776 PMCID: PMC9960215 DOI: 10.1186/s12957-023-02948-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2022] [Accepted: 02/14/2023] [Indexed: 02/27/2023] Open
Abstract
BACKGROUND With the advance in genome-wide analyses, genetic alternations have been found to play an important role in carcinogenesis and aggressiveness of UC. Through bioinformatic analysis of gene expression profiles of urinary bladder urothelial carcinoma (UBUC) from publicly available GEO dataset (GSE31684), Zinc finger and SCAN domain containing 4 (ZSCAN4) was identified as a significant downregulated gene in muscle-invasive bladder cancer when compared with non-muscle-invasive bladder cancer. METHODS The expression of ZSCAN4 was evaluated by immunohistochemistry in 340 upper urinary tract urothelial carcinomas (UTUCs) and 295 UBUCs. The expression profiles of ZSCAN4 and potential signaling pathways were analyzed bioinformatically. RESULTS In UTUC, low expression of ZSCAN4 was significantly associated with advanced primary pT stage (P = 0.011), increased nodal metastasis (P = 0.002) and increased vascular invasion (P = 0.019). In UBUC, low expression of ZSCAN4 was significantly correlated with advanced primary pT stage (P < 0.001), increased nodal metastasis (P = 0.001), high histological grade (P = 0.003) and increased vascular invasion (P = 0.003). In survival analysis, low expression of ZSCAN4 acted as an independent negative prognostic factor for disease-specific survival and metastasis-free survival both in UTUC and UBUC. Gene ontology analysis showed that ZSCAN4 mRNA and its co-downregulated genes are associated with the mitotic cell cycle. CONCLUSIONS Low expression of ZSCAN4 predicted worse outcome in urothelial carcinoma and might have potential regulatory role in cell mitosis.
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Affiliation(s)
- Hong-Lin He
- grid.411447.30000 0004 0637 1806Department of Pathology, E-DA Cancer Hospital, I-Shou University, Kaohsiung, Taiwan
| | - Hong-Yue Lai
- grid.413876.f0000 0004 0572 9255Department of Medical Research, Chi Mei Medical Center, Tainan, Taiwan
| | - Ti-Chun Chan
- grid.413876.f0000 0004 0572 9255Department of Medical Research, Chi Mei Medical Center, Tainan, Taiwan ,grid.59784.370000000406229172National Institute of Cancer Research, National Health Research Institutes, Tainan, Taiwan
| | - Chung-Hsi Hsing
- grid.413876.f0000 0004 0572 9255Department of Medical Research, Chi Mei Medical Center, Tainan, Taiwan ,grid.413876.f0000 0004 0572 9255Department of Anesthesiology, Chi Mei Medical Center, Tainan, Taiwan
| | - Steven K. Huang
- grid.413876.f0000 0004 0572 9255Division of Urology, Department of Surgery, Chi Mei Medical Center, Tainan, Taiwan ,grid.411315.30000 0004 0634 2255Department of Biotechnology, Chia Nan University of Pharmacy and Science, Tainan, Taiwan
| | - Kun-Lin Hsieh
- grid.413876.f0000 0004 0572 9255Division of Urology, Department of Surgery, Chi Mei Medical Center, Tainan, Taiwan
| | - Tzu-Ju Chen
- grid.413876.f0000 0004 0572 9255Department of Clinical Pathology, Chi Mei Medical Center, Tainan, Taiwan ,grid.411636.70000 0004 0634 2167Department of Medical Technology, Chung Hwa University of Medical Technology, Tainan, Taiwan
| | - Wan-Shan Li
- grid.411636.70000 0004 0634 2167Department of Medical Technology, Chung Hwa University of Medical Technology, Tainan, Taiwan ,grid.413876.f0000 0004 0572 9255Department of Pathology, Chi Mei Medical Center, Tainan, Taiwan
| | - Yu-Hsuan Kuo
- grid.413876.f0000 0004 0572 9255Division of Hematology and Oncology, Department of Internal Medicine, Chi-Mei Medical Center, Tainan, Taiwan ,College of Pharmacy and Science, Chia Nan University, Tainan, Taiwan
| | - Yow-Ling Shiue
- Institute of Precision Medicine, National Sun Yat-Sen University, Kaohsiung, Taiwan.
| | - Chien-Feng Li
- Department of Medical Research, Chi Mei Medical Center, Tainan, Taiwan. .,National Institute of Cancer Research, National Health Research Institutes, Tainan, Taiwan. .,Institute of Precision Medicine, National Sun Yat-Sen University, Kaohsiung, Taiwan.
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11
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Su M, Lien J, Anilao A, Guo T. Enhanced Single-Strand Breaks of a Nucleic Acid by Gold Nanoparticles under X-ray Irradiation. J Phys Chem Lett 2023; 14:1214-1221. [PMID: 36716218 DOI: 10.1021/acs.jpclett.2c03885] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
The hydroxyl radical concentration-dependent yield of single-strand breaks (SSBs), obtained through correction of scavenging and hindrance effects caused by gold nanoparticles (AuNPs), for fluorophore- and quencher-labeled DNA on AuNPs was 10 times that of free DNA based on fluorescence measurements of X-ray-irradiated DNA on AuNPs. By comparing the fluorescence data that revealed the number of SSBs with the results of mass spectrometry measurements that detected the total damage to DNA, we found that SSBs dominated DNA damage for DNA on AuNPs whereas non-SSB damage dominated for free DNA. The yield of RNA SSBs under X-ray irradiation was similar to that of DNA in the presence of AuNPs, whereas free RNA was more resistive to radiation than DNA. These results indicated the enhanced SSBs were likely catalyzed through the conversion from nucleobase damage to SSBs by AuNPs. The outcome of this work impacts materials and environmental science, sensing, nanotechnology, biology, and medicine.
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Affiliation(s)
- Mengqi Su
- Department of Chemistry, University of California, One Shields Avenue, Davis, California 95616, United States
| | - Jennifer Lien
- Department of Chemistry, University of California, One Shields Avenue, Davis, California 95616, United States
| | - Auddy Anilao
- Department of Chemistry, University of California, One Shields Avenue, Davis, California 95616, United States
| | - Ting Guo
- Department of Chemistry, University of California, One Shields Avenue, Davis, California 95616, United States
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12
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Role of Histone Tails and Single Strand DNA Breaks in Nucleosomal Arrest of RNA Polymerase. Int J Mol Sci 2023; 24:ijms24032295. [PMID: 36768621 PMCID: PMC9917218 DOI: 10.3390/ijms24032295] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2022] [Revised: 01/13/2023] [Accepted: 01/19/2023] [Indexed: 01/26/2023] Open
Abstract
Transcription through nucleosomes by RNA polymerases (RNAP) is accompanied by formation of small intranucleosomal DNA loops (i-loops). The i-loops form more efficiently in the presence of single-strand breaks or gaps in a non-template DNA strand (NT-SSBs) and induce arrest of transcribing RNAP, thus allowing detection of NT-SSBs by the enzyme. Here we examined the role of histone tails and extranucleosomal NT-SSBs in i-loop formation and arrest of RNAP during transcription of promoter-proximal region of nucleosomal DNA. NT-SSBs present in linker DNA induce arrest of RNAP +1 to +15 bp in the nucleosome, suggesting formation of the i-loops; the arrest is more efficient in the presence of the histone tails. Consistently, DNA footprinting reveals formation of an i-loop after stalling RNAP at the position +2 and backtracking to position +1. The data suggest that histone tails and NT-SSBs present in linker DNA strongly facilitate formation of the i-loops during transcription through the promoter-proximal region of nucleosomal DNA.
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13
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De la Cruz G, Nikolaishvili-Feinberg N, Gershon TR. Automated Immunofluorescence Staining for Analysis of DNA Damage and Apoptosis in Brain Sections. Methods Mol Biol 2023; 2583:55-61. [PMID: 36418725 DOI: 10.1007/978-1-0716-2752-5_6] [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
Neural progenitors show a strong tendency to undergo apoptosis in response to DNA damage, and both impaired DNA repair and increased neural progenitor apoptosis are associated with microcephaly. Here we present an immunohistochemistry-based method for assessing DNA damage and apoptosis in the neonatal mouse brain. These methods are suitable for determining in specific experimental conditions the fractions of cells with DNA double-strand breaks, the fractions of cells undergoing apoptosis, or both. While DNA damage in neural progenitors can trigger apoptosis, inappropriate apoptosis may also result from other processes. Simultaneous analysis of DNA damage and apoptosis in mouse models of microcephaly can determine how genetic instability and cell death contribute to the observed phenotype.
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Affiliation(s)
- Gabriela De la Cruz
- Lineberger Comprehensive Cancer Center, The University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
- Pathology Services Core, The University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Nana Nikolaishvili-Feinberg
- Lineberger Comprehensive Cancer Center, The University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
- Pathology Services Core, The University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Timothy R Gershon
- Lineberger Comprehensive Cancer Center, The University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.
- Department of Neurology, The University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.
- UNC Neuroscience Center, The University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.
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14
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Wang D, Wu W, Callen E, Pavani R, Zolnerowich N, Kodali S, Zong D, Wong N, Noriega S, Nathan WJ, Matos-Rodrigues G, Chari R, Kruhlak MJ, Livak F, Ward M, Caldecott K, Di Stefano B, Nussenzweig A. Active DNA demethylation promotes cell fate specification and the DNA damage response. Science 2022; 378:983-989. [PMID: 36454826 PMCID: PMC10196940 DOI: 10.1126/science.add9838] [Citation(s) in RCA: 30] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
Abstract
Neurons harbor high levels of single-strand DNA breaks (SSBs) that are targeted to neuronal enhancers, but the source of this endogenous damage remains unclear. Using two systems of postmitotic lineage specification-induced pluripotent stem cell-derived neurons and transdifferentiated macrophages-we show that thymidine DNA glycosylase (TDG)-driven excision of methylcytosines oxidized with ten-eleven translocation enzymes (TET) is a source of SSBs. Although macrophage differentiation favors short-patch base excision repair to fill in single-nucleotide gaps, neurons also frequently use the long-patch subpathway. Disrupting this gap-filling process using anti-neoplastic cytosine analogs triggers a DNA damage response and neuronal cell death, which is dependent on TDG. Thus, TET-mediated active DNA demethylation promotes endogenous DNA damage, a process that normally safeguards cell identity but can also provoke neurotoxicity after anticancer treatments.
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Affiliation(s)
- Dongpeng Wang
- Laboratory of Genome Integrity, National Cancer Institute NIH, Bethesda, MD, USA
| | - Wei Wu
- Laboratory of Genome Integrity, National Cancer Institute NIH, Bethesda, MD, USA
- State Key Laboratory of Molecular Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, Shanghai, China
| | - Elsa Callen
- Laboratory of Genome Integrity, National Cancer Institute NIH, Bethesda, MD, USA
| | - Raphael Pavani
- Laboratory of Genome Integrity, National Cancer Institute NIH, Bethesda, MD, USA
| | - Nicholas Zolnerowich
- Laboratory of Genome Integrity, National Cancer Institute NIH, Bethesda, MD, USA
| | - Srikanth Kodali
- Stem Cells and Regenerative Medicine, Center for Cell and Gene Therapy, Department of Molecular and Cellular Biology and Dan L. Duncan Comprehensive Cancer Center, Baylor College of Medicine, Houston, TX, USA
- Center for Cancer Epigenetics, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Dali Zong
- Laboratory of Genome Integrity, National Cancer Institute NIH, Bethesda, MD, USA
| | - Nancy Wong
- Laboratory of Genome Integrity, National Cancer Institute NIH, Bethesda, MD, USA
| | - Santiago Noriega
- Laboratory of Genome Integrity, National Cancer Institute NIH, Bethesda, MD, USA
| | - William J. Nathan
- Laboratory of Genome Integrity, National Cancer Institute NIH, Bethesda, MD, USA
| | | | - Raj Chari
- Genome Modification Core, Frederick National Laboratory for Cancer Research, Frederick, MD, USA
| | - Michael J. Kruhlak
- Laboratory of Cancer Biology and Genetics, National Cancer Institute, NIH, Bethesda, MD, USA
| | - Ferenc Livak
- Laboratory of Genome Integrity, National Cancer Institute NIH, Bethesda, MD, USA
| | - Michael Ward
- National Institute of Neurological Disorders and Stroke, NIH, Bethesda, MD, USA
| | - Keith Caldecott
- Genome Damage and Stability Centre, University of Sussex, Falmer Brighton, UK
| | - Bruno Di Stefano
- Stem Cells and Regenerative Medicine, Center for Cell and Gene Therapy, Department of Molecular and Cellular Biology and Dan L. Duncan Comprehensive Cancer Center, Baylor College of Medicine, Houston, TX, USA
- Center for Cancer Epigenetics, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - André Nussenzweig
- Laboratory of Genome Integrity, National Cancer Institute NIH, Bethesda, MD, USA
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15
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Li J, Zhao H, McMahon A, Yan S. APE1 assembles biomolecular condensates to promote the ATR-Chk1 DNA damage response in nucleolus. Nucleic Acids Res 2022; 50:10503-10525. [PMID: 36200829 PMCID: PMC9561277 DOI: 10.1093/nar/gkac853] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2022] [Revised: 09/14/2022] [Accepted: 10/03/2022] [Indexed: 11/13/2022] Open
Abstract
Multifunctional protein APE1/APEX1/HAP1/Ref-1 (designated as APE1) plays important roles in nuclease-mediated DNA repair and redox regulation in transcription. However, it is unclear how APE1 regulates the DNA damage response (DDR) pathways. Here we show that siRNA-mediated APE1-knockdown or APE1 inhibitor treatment attenuates the ATR–Chk1 DDR under stress conditions in multiple immortalized cell lines. Congruently, APE1 overexpression (APE1-OE) activates the ATR DDR under unperturbed conditions, which is independent of APE1 nuclease and redox functions. Structural and functional analysis reveals a direct requirement of the extreme N-terminal motif within APE1 in the assembly of distinct biomolecular condensates in vitro and DNA/RNA-independent activation of the ATR DDR. Overexpressed APE1 co-localizes with nucleolar NPM1 and assembles biomolecular condensates in nucleoli in cancer but not non-malignant cells, which recruits ATR and activator molecules TopBP1 and ETAA1. APE1 protein can directly activate ATR to phosphorylate its substrate Chk1 in in vitro kinase assays. W119R mutant of APE1 is deficient in nucleolar condensation, and is incapable of activating nucleolar ATR DDR in cells and ATR kinase in vitro. APE1-OE-induced nucleolar ATR DDR activation leads to compromised ribosomal RNA transcription and reduced cell viability. Taken together, we propose distinct mechanisms by which APE1 regulates ATR DDR pathways.
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Affiliation(s)
- Jia Li
- Department of Biological Sciences, University of North Carolina at Charlotte, Charlotte, NC 28223, USA
| | - Haichao Zhao
- Department of Biological Sciences, University of North Carolina at Charlotte, Charlotte, NC 28223, USA
| | - Anne McMahon
- Department of Biological Sciences, University of North Carolina at Charlotte, Charlotte, NC 28223, USA
| | - Shan Yan
- Department of Biological Sciences, University of North Carolina at Charlotte, Charlotte, NC 28223, USA.,School of Data Science, University of North Carolina at Charlotte, Charlotte, NC 28223, USA.,Center for Biomedical Engineering and Science, University of North Carolina at Charlotte, Charlotte, NC 28223, USA
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16
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Mechanisms of microRNA action in rectal cancer radiotherapy. Chin Med J (Engl) 2022; 135:2017-2025. [PMID: 35943251 PMCID: PMC9746734 DOI: 10.1097/cm9.0000000000002139] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
ABSTRACT Preoperative neoadjuvant chemoradiotherapy, combined with total mesorectal excision, has become the standard treatment for advanced localized rectal cancer (RC). However, the biological complexity and heterogeneity of tumors may contribute to cancer recurrence and metastasis in patients with radiotherapy-resistant RC. The identification of factors leading to radioresistance and markers of radiosensitivity is critical to identify responsive patients and improve radiotherapy outcomes. MicroRNAs (miRNAs) are small, endogenous, and noncoding RNAs that affect various cellular and molecular targets. miRNAs have been shown to play important roles in multiple biological processes associated with RC. In this review, we summarized the signaling pathways of miRNAs, including apoptosis, autophagy, the cell cycle, DNA damage repair, proliferation, and metastasis during radiotherapy in patients with RC. Also, we evaluated the potential role of miRNAs as radiotherapeutic biomarkers for RC.
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17
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Structure of an Intranucleosomal DNA Loop That Senses DNA Damage during Transcription. Cells 2022; 11:cells11172678. [PMID: 36078089 PMCID: PMC9454427 DOI: 10.3390/cells11172678] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2022] [Revised: 08/22/2022] [Accepted: 08/24/2022] [Indexed: 11/16/2022] Open
Abstract
Transcription through chromatin by RNA polymerase II (Pol II) is accompanied by the formation of small intranucleosomal DNA loops containing the enzyme (i-loops) that are involved in survival of core histones on the DNA and arrest of Pol II during the transcription of damaged DNA. However, the structures of i-loops have not been determined. Here, the structures of the intermediates formed during transcription through a nucleosome containing intact or damaged DNA were studied using biochemical approaches and electron microscopy. After RNA polymerase reaches position +24 from the nucleosomal boundary, the enzyme can backtrack to position +20, where DNA behind the enzyme recoils on the surface of the histone octamer, forming an i-loop that locks Pol II in the arrested state. Since the i-loop is formed more efficiently in the presence of SSBs positioned behind the transcribing enzyme, the loop could play a role in the transcription-coupled repair of DNA damage hidden in the chromatin structure.
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18
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Zhang J, Wang Y, Wang Y, Zhang P, Chen HY, Huang S. Discrimination between Different DNA Lesions by Monitoring Single-Molecule Polymerase Stalling Kinetics during Nanopore Sequencing. NANO LETTERS 2022; 22:5561-5569. [PMID: 35713465 DOI: 10.1021/acs.nanolett.2c01833] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
O6-Carboxymethylguanosine (O6-CMG), O6-methylguanosine (O6-MeG), and abasic site (AP site) are DNA lesions induced by alkylating agents. Identification of these lesions in DNA may aid in understanding their relevance to carcinogenesis and may be used for diagnosis. Nanopore sequencing (NPS) may directly report nucleotide modifications solely from the nanopore readout. However, the conventional NPS strategy still suffers from interferences from neighboring sequences. Instead, by observation of the enzymatic stalling kinetics caused by the O6-CMG, O6-MeG, or AP site, discrimination between different DNA lesions is directly achieved. This strategy is not interfered with by the sequence context around the lesion. The lesion, which retards the movement of the DNA through the pore, efficiently prohibits misreading of the DNA lesion. These results suggest a new strategy in the identification of DNA lesions or DNA modifications. It also provides a high-resolution biophysical tool to investigate enzymatic kinetics caused by DNA lesions and the corresponding enzymes.
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Affiliation(s)
- Jinyue Zhang
- State Key Laboratory of Analytical Chemistry for Life Sciences, School of Chemistry and Chemical Engineering, Nanjing University, 210023 Nanjing, China
- Chemistry and Biomedicine Innovation Center (ChemBIC), Nanjing University, 210023 Nanjing, China
| | - Yu Wang
- State Key Laboratory of Analytical Chemistry for Life Sciences, School of Chemistry and Chemical Engineering, Nanjing University, 210023 Nanjing, China
- Chemistry and Biomedicine Innovation Center (ChemBIC), Nanjing University, 210023 Nanjing, China
| | - Yuqin Wang
- State Key Laboratory of Analytical Chemistry for Life Sciences, School of Chemistry and Chemical Engineering, Nanjing University, 210023 Nanjing, China
- Chemistry and Biomedicine Innovation Center (ChemBIC), Nanjing University, 210023 Nanjing, China
| | - Panke Zhang
- State Key Laboratory of Analytical Chemistry for Life Sciences, School of Chemistry and Chemical Engineering, Nanjing University, 210023 Nanjing, China
| | - Hong-Yuan Chen
- State Key Laboratory of Analytical Chemistry for Life Sciences, School of Chemistry and Chemical Engineering, Nanjing University, 210023 Nanjing, China
| | - Shuo Huang
- State Key Laboratory of Analytical Chemistry for Life Sciences, School of Chemistry and Chemical Engineering, Nanjing University, 210023 Nanjing, China
- Chemistry and Biomedicine Innovation Center (ChemBIC), Nanjing University, 210023 Nanjing, China
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19
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Hasan A, Rizvi SF, Parveen S, Mir SS. Molecular chaperones in DNA repair mechanisms: Role in genomic instability and proteostasis in cancer. Life Sci 2022; 306:120852. [DOI: 10.1016/j.lfs.2022.120852] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2022] [Revised: 07/14/2022] [Accepted: 07/27/2022] [Indexed: 01/09/2023]
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20
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Exploring the Origin and Physiological Significance of DNA Double Strand Breaks in the Developing Neuroretina. Int J Mol Sci 2022; 23:ijms23126449. [PMID: 35742893 PMCID: PMC9224223 DOI: 10.3390/ijms23126449] [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: 05/14/2022] [Revised: 06/06/2022] [Accepted: 06/07/2022] [Indexed: 02/04/2023] Open
Abstract
Genetic mosaicism is an intriguing physiological feature of the mammalian brain that generates altered genetic information and provides cellular, and prospectively functional, diversity in a manner similar to that of the immune system. However, both its origin and its physiological significance remain poorly characterized. Most, if not all, cases of somatic mosaicism require prior generation and repair of DNA double strand breaks (DSBs). The relationship between DSB generation, neurogenesis, and early neuronal cell death revealed by our studies in the developing retina provides new perspectives on the different mechanisms that contribute to DNA rearrangements in the developing brain. Here, we speculate on the physiological significance of these findings.
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21
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Roy A, Kandettu A, Ray S, Chakrabarty S. Mitochondrial DNA replication and repair defects: Clinical phenotypes and therapeutic interventions. BIOCHIMICA ET BIOPHYSICA ACTA. BIOENERGETICS 2022; 1863:148554. [PMID: 35341749 DOI: 10.1016/j.bbabio.2022.148554] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2021] [Revised: 03/06/2022] [Accepted: 03/16/2022] [Indexed: 12/15/2022]
Abstract
Mitochondria is a unique cellular organelle involved in multiple cellular processes and is critical for maintaining cellular homeostasis. This semi-autonomous organelle contains its circular genome - mtDNA (mitochondrial DNA), that undergoes continuous cycles of replication and repair to maintain the mitochondrial genome integrity. The majority of the mitochondrial genes, including mitochondrial replisome and repair genes, are nuclear-encoded. Although the repair machinery of mitochondria is quite efficient, the mitochondrial genome is highly susceptible to oxidative damage and other types of exogenous and endogenous agent-induced DNA damage, due to the absence of protective histones and their proximity to the main ROS production sites. Mutations in replication and repair genes of mitochondria can result in mtDNA depletion and deletions subsequently leading to mitochondrial genome instability. The combined action of mutations and deletions can result in compromised mitochondrial genome maintenance and lead to various mitochondrial disorders. Here, we review the mechanism of mitochondrial DNA replication and repair process, key proteins involved, and their altered function in mitochondrial disorders. The focus of this review will be on the key genes of mitochondrial DNA replication and repair machinery and the clinical phenotypes associated with mutations in these genes.
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Affiliation(s)
- Abhipsa Roy
- Department of Cell and Molecular Biology, Manipal School of Life Sciences, Manipal Academy of Higher Education, Manipal 576104, Karnataka, India
| | - Amoolya Kandettu
- Department of Cell and Molecular Biology, Manipal School of Life Sciences, Manipal Academy of Higher Education, Manipal 576104, Karnataka, India
| | - Swagat Ray
- Department of Life Sciences, School of Life and Environmental Sciences, University of Lincoln, Lincoln LN6 7TS, United Kingdom
| | - Sanjiban Chakrabarty
- Department of Cell and Molecular Biology, Manipal School of Life Sciences, Manipal Academy of Higher Education, Manipal 576104, Karnataka, India.
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22
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Konopka A, Atkin JD. DNA Damage, Defective DNA Repair, and Neurodegeneration in Amyotrophic Lateral Sclerosis. Front Aging Neurosci 2022; 14:786420. [PMID: 35572138 PMCID: PMC9093740 DOI: 10.3389/fnagi.2022.786420] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Accepted: 03/07/2022] [Indexed: 12/16/2022] Open
Abstract
DNA is under constant attack from both endogenous and exogenous sources, and when damaged, specific cellular signalling pathways respond, collectively termed the “DNA damage response.” Efficient DNA repair processes are essential for cellular viability, although they decline significantly during aging. Not surprisingly, DNA damage and defective DNA repair are now increasingly implicated in age-related neurodegenerative diseases, including amyotrophic lateral sclerosis (ALS). ALS affects both upper and lower motor neurons in the brain, brainstem and spinal cord, leading to muscle wasting due to denervation. DNA damage is increasingly implicated in the pathophysiology of ALS, and interestingly, the number of DNA damage or repair proteins linked to ALS is steadily growing. This includes TAR DNA binding protein 43 (TDP-43), a DNA/RNA binding protein that is present in a pathological form in almost all (97%) cases of ALS. Hence TDP-43 pathology is central to neurodegeneration in this condition. Fused in Sarcoma (FUS) bears structural and functional similarities to TDP-43 and it also functions in DNA repair. Chromosome 9 open reading frame 72 (C9orf72) is also fundamental to ALS because mutations in C9orf72 are the most frequent genetic cause of both ALS and related condition frontotemporal dementia, in European and North American populations. Genetic variants encoding other proteins involved in the DNA damage response (DDR) have also been described in ALS, including FUS, SOD1, SETX, VCP, CCNF, and NEK1. Here we review recent evidence highlighting DNA damage and defective DNA repair as an important mechanism linked to neurodegeneration in ALS.
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Affiliation(s)
- Anna Konopka
- Centre for Motor Neuron Disease Research, Faculty of Medicine, Macquarie Medical School, Health and Human Sciences, Macquarie University, Sydney, NSW, Australia
- *Correspondence: Anna Konopka,
| | - Julie D. Atkin
- Centre for Motor Neuron Disease Research, Faculty of Medicine, Macquarie Medical School, Health and Human Sciences, Macquarie University, Sydney, NSW, Australia
- La Trobe Institute for Molecular Science, La Trobe University, Melbourne, VIC, Australia
- Julie D. Atkin,
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23
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Pradhan S, Gao R, Bush K, Zhang N, Wairkar YP, Sarkar PS. Polyglutamine Expansion in Huntingtin and Mechanism of DNA Damage Repair Defects in Huntington’s Disease. Front Cell Neurosci 2022; 16:837576. [PMID: 35444517 PMCID: PMC9013776 DOI: 10.3389/fncel.2022.837576] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Accepted: 02/07/2022] [Indexed: 12/27/2022] Open
Abstract
Emerging evidence suggests that DNA repair deficiency and genome instability may be the impending signs of many neurological diseases. Genome-wide association (GWAS) studies have established a strong correlation between genes that play a role in DNA damage repair and many neurodegenerative diseases, including Huntington’s disease (HD), and several other trinucleotides repeat expansion-related hereditary ataxias. Recently, many reports have documented a significant role played by the DNA repair processes in aging and in modifying many neurodegenerative diseases, early during their progression. Studies from our lab and others have now begun to understand the mechanisms that cause defective DNA repair in HD and surprisingly, many proteins that have a strong link to known neurodegenerative diseases seem to be important players in these cellular pathways. Mutations in huntingtin (HTT) gene that lead to polyglutamine repeat expansion at the N-terminal of HTT protein has been shown to disrupt transcription-coupled DNA repair process, a specialized DNA repair process associated with transcription. Due to the recent progress made in understanding the mechanisms of DNA repair in relation to HD, in this review, we will mainly focus on the mechanisms by which the wild-type huntingtin (HTT) protein helps in DNA repair during transcription, and the how polyglutamine expansions in HTT impedes this process in HD. Further studies that identify new players in DNA repair will help in our understanding of this process in neurons. Furthermore, it should help us understand how various DNA repair mechanism(s) coordinate to maintain the normal physiology of neurons, and provide insights for the development of novel drugs at prodromal stages of these neurodegenerative diseases.
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Affiliation(s)
- Subrata Pradhan
- Department of Neurology, University of Texas Medical Branch, Galveston, TX, United States
| | - Rui Gao
- Department of Neurology, University of Texas Medical Branch, Galveston, TX, United States
| | - Keegan Bush
- Department of Neuroscience, Cell Biology and Anatomy, University of Texas Medical Branch, Galveston, TX, United States
| | - Nan Zhang
- Department of Neurology, Houston Methodist Research Institute, Houston, TX, United States
| | - Yogesh P. Wairkar
- Department of Neurology, University of Texas Medical Branch, Galveston, TX, United States
- Department of Neuroscience, Cell Biology and Anatomy, University of Texas Medical Branch, Galveston, TX, United States
| | - Partha S. Sarkar
- Department of Neurology, University of Texas Medical Branch, Galveston, TX, United States
- Department of Neuroscience, Cell Biology and Anatomy, University of Texas Medical Branch, Galveston, TX, United States
- *Correspondence: Partha S. Sarkar,
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24
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Caldecott KW, Ward ME, Nussenzweig A. The threat of programmed DNA damage to neuronal genome integrity and plasticity. Nat Genet 2022; 54:115-120. [PMID: 35145299 DOI: 10.1038/s41588-021-01001-y] [Citation(s) in RCA: 28] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2021] [Accepted: 12/09/2021] [Indexed: 02/08/2023]
Abstract
The neuronal genome is particularly sensitive to loss or attenuation of DNA repair, and many neurological diseases ensue when DNA repair is impaired. It is well-established that the neuronal genome is subjected to stochastic DNA damage, most likely because of extensive oxidative stress in the brain. However, recent studies have identified unexpected high levels of 'programmed' DNA breakage in neurons, which we propose arise during physiological DNA metabolic processes intrinsic to neuronal development, differentiation and maintenance. The role of programmed DNA breaks in normal neuronal physiology and disease remains relatively unexplored thus far. However, bulk and single-cell sequencing analyses of neurodegenerative diseases have revealed age-related somatic mutational signatures that are enriched in regulatory regions of the genome. Here, we explore a paradigm of DNA repair in neurons, in which the genome is safeguarded from erroneous impacts of programmed genome breakage intrinsic to normal neuronal function.
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Affiliation(s)
- Keith W Caldecott
- Genome Damage and Stability Centre, School of Life Sciences, University of Sussex, Brighton, UK.
| | - Michael E Ward
- National Institute of Neurological Disorders and Stroke, NIH, Bethesda, MD, USA.
| | - André Nussenzweig
- Laboratory of Genome Integrity, National Cancer Institute, NIH, Bethesda, MD, USA.
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25
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Bhattacharjee S, Rehman I, Nandy S, Das BB. Post-translational regulation of Tyrosyl-DNA phosphodiesterase (TDP1 and TDP2) for the repair of the trapped topoisomerase-DNA covalent complex. DNA Repair (Amst) 2022; 111:103277. [DOI: 10.1016/j.dnarep.2022.103277] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2021] [Revised: 12/24/2021] [Accepted: 01/20/2022] [Indexed: 12/23/2022]
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26
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Raghubeer S, Matsha TE. Methylenetetrahydrofolate (MTHFR), the One-Carbon Cycle, and Cardiovascular Risks. Nutrients 2021; 13:nu13124562. [PMID: 34960114 PMCID: PMC8703276 DOI: 10.3390/nu13124562] [Citation(s) in RCA: 61] [Impact Index Per Article: 20.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2021] [Revised: 12/07/2021] [Accepted: 12/15/2021] [Indexed: 02/06/2023] Open
Abstract
The 5-10-methylenetetrahydrofolate reductase (MTHFR) enzyme is vital for cellular homeostasis due to its key functions in the one-carbon cycle, which include methionine and folate metabolism and protein, DNA, and RNA synthesis. The enzyme is responsible for maintaining methionine and homocysteine (Hcy) balance to prevent cellular dysfunction. Polymorphisms in the MTHFR gene, especially C677T, have been associated with various diseases, including cardiovascular diseases (CVDs), cancer, inflammatory conditions, diabetes, and vascular disorders. The C677T MTHFR polymorphism is thought to be the most common cause of elevated Hcy levels, which is considered an independent risk factor for CVD. This polymorphism results in an amino acid change from alanine to valine, which prevents optimal functioning of the enzyme at temperatures above 37 °C. Many studies have been conducted to determine whether there is an association between the C677T polymorphism and increased risk for CVD. There is much evidence in favour of this association, while several studies have concluded that the polymorphism cannot be used to predict CVD development or progression. This review discusses current research regarding the C677T polymorphism and its relationship with CVD, inflammation, diabetes, and epigenetic regulation and compares the evidence provided for and against the association with CVD.
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27
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Liu C, Qie Y, Zhao L, Li M, Guo LH. A High-Throughput Platform for the Rapid Quantification of Phosphorylated Histone H2AX in Cell Lysates Based on Microplate Electrochemiluminescence Immunosensor Array. ACS Sens 2021; 6:3724-3732. [PMID: 34591450 DOI: 10.1021/acssensors.1c01502] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Sensitive detection of phosphorylated histone H2AX (γH2AX) in cells as a biomarker of DNA double-strand breaks has great significance in the field of molecular toxicology and life science research. However, current γH2AX detection methods require labor- and time-consuming steps. Here, for the first time, we designed a simple electrochemiluminescence (ECL) immunoassay integrated with a microplate-based sensor array to realize sensitive and high-throughput detection of γH2AX in cell lysates. Under the optimized conditions, this ECL immunosensor array could linearly respond to γH2AX concentrations in the range from 2 × 102 to 1 × 105 pg/mL. In addition, our approach possessed excellent specificity and satisfactory reproducibility, and its practicality was verified in real cell lysates. The whole process including instrumental and manual operation was completed in no more than 3 h. This study provides a convenient and rapid alternative method for the sensitive quantification of γH2AX, which shows promising application in high-throughput screening of genotoxic chemicals and drug candidates.
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Affiliation(s)
- Chang Liu
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, People’s Republic of China
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, People’s Republic of China
| | - Yu Qie
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, People’s Republic of China
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, People’s Republic of China
| | - Lixia Zhao
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, People’s Republic of China
- School of Environment, Hangzhou Institute for Advanced Study, UCAS, Hangzhou 310007, P. R. China
| | - Minjie Li
- College of Quality and Safety Engineering, China Jiliang University, Hangzhou 310018, Zhejiang, People’s Republic of China
| | - Liang-Hong Guo
- College of Quality and Safety Engineering, China Jiliang University, Hangzhou 310018, Zhejiang, People’s Republic of China
- Institute of Environmental and Health Sciences, China Jiliang University, Hangzhou 310018, Zhejiang, People’s Republic of China
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28
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Kuraishi Y, Uehara T, Muraki T, Iwaya M, Kinugawa Y, Nakajima T, Watanabe T, Miyagawa Y, Umemura T. Impact of DNA double-strand breaks on pancreaticobiliary maljunction carcinogenesis. Diagn Pathol 2021; 16:72. [PMID: 34372868 PMCID: PMC8353780 DOI: 10.1186/s13000-021-01132-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Accepted: 07/22/2021] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND Pancreaticobiliary maljunction (PBM) is a condition characterized by chronic inflammation due to refluxed pancreatic juice into the biliary tract that is associated with an elevated risk of biliary tract cancer. DNA double-strand breaks (DSBs) are considered the most serious form of DNA damage. DSBs are provoked by inflammatory cell damage and are recognized as an important oncogenic event in several cancers. This study used γ-H2AX, an established marker of DSB formation, to evaluate the impact of DNA damage on carcinogenesis in PBM. METHODS We investigated γ-H2AX expression immunohistochemically in gallbladder epithelium samples obtained from 71 PBM cases and 19 control cases. RESULTS Fourteen PBM cases with gallbladder adenocarcinoma were evaluated at non-neoplastic regions. A wide range of nuclear γ-H2AX staining was detected in all PBM and control specimens. γ-H2AX expression was significantly higher in PBM cases versus controls (median γ-H2AX-positive proportion: 14.4 % vs. 4.4 %, p = 0.001). Among the PBM cases, γ-H2AX expression was significantly higher in patients with carcinoma than in those without (median γ-H2AX-positive proportion: 21.4 % vs. 11.0 %, p = 0.031). CONCLUSIONS DSBs occurred significantly more abundantly in the PBM gallbladder mucosa, especially in the context of cancer, indicating an involvement in PBM-related carcinogenesis.
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Affiliation(s)
- Yasuhiro Kuraishi
- Department of Gastroenterology, Shinshu University School of Medicine, Matsumoto, Japan
| | - Takeshi Uehara
- Department of Laboratory Medicine, Shinshu University School of Medicine, Matsumoto, Japan.
| | - Takashi Muraki
- Department of Gastroenterology, North Alps Medical Center Azumi Hospital, Ikeda, Japan
| | - Mai Iwaya
- Department of Laboratory Medicine, Shinshu University School of Medicine, Matsumoto, Japan
| | - Yasuhiro Kinugawa
- Department of Laboratory Medicine, Shinshu University School of Medicine, Matsumoto, Japan
| | - Tomoyuki Nakajima
- Department of Laboratory Medicine, Shinshu University School of Medicine, Matsumoto, Japan
| | - Takayuki Watanabe
- Department of Gastroenterology, Shinshu University School of Medicine, Matsumoto, Japan
| | - Yusuke Miyagawa
- Department of Surgery, Shinshu University School of Medicine, Matsumoto, Japan
| | - Takeji Umemura
- Department of Gastroenterology, Shinshu University School of Medicine, Matsumoto, Japan.,Department of Life Innovation, Institute for Biomedical Sciences, Shinshu University School of Medicine, Matsumoto, Japan
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29
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Becerra-Solano LE, Mateos-Sánchez L, López-Muñoz E. Microcephaly, an etiopathogenic vision. Pediatr Neonatol 2021; 62:354-360. [PMID: 34112604 DOI: 10.1016/j.pedneo.2021.05.008] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/04/2020] [Revised: 03/30/2021] [Accepted: 05/17/2021] [Indexed: 11/18/2022] Open
Abstract
Microcephaly is defined by an occipital-frontal head circumference (OFD) 2 standard deviations (SD) smaller than the average expected for age, gender and population. Its incidence has been reported between 1.3 and 150 cases per 100,000 births. Currently, new clinical characteristics, causes and pathophysiological mechanisms related to microcephaly continue to be identified. Its etiology is varied and heterogeneous, with genetic and non-genetic factors that produce alterations in differentiation, proliferation, migration, repair of damage to deoxyribonucleic acid and neuronal apoptosis. It requires a multidisciplinary diagnostic approach that includes a medical history, detailed prenatal and postnatal clinical evaluation, cerebral magnetic resonance imaging, neuropsychological evaluation, and in some cases complementary tests such as metabolic screening, tests to rule out infectious processes and genetic testing. There is no specific treatment or intervention to increase cerebral growth; however, timely intervention strategies and programs can be established to improve motor and neurocognitive development, as well as to provide genetic counseling. The objective of this work is to review the available information and reinforce the proposal to carry out an etiopathogenic approach for microcephaly diagnosis and management.
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Affiliation(s)
- Luis Eduardo Becerra-Solano
- Medical Research Unit in Reproductive Medicine, Unidad Médica de Alta Especialidad, Hospital de Gineco Obstetricia No. 4, "Luis Castelazo Ayala", Instituto Mexicano del Seguro Social, Río Magdalena 289, Level 6, Laboratory K, Colonia Tizapan San Ángel, Alcaldía Álvaro Obregón, C.P. 01090, Mexico City, Mexico
| | - Leovigildo Mateos-Sánchez
- Neonatal Intensive Care Unit, Unidad Médica de Alta Especialidad, Hospital de Gineco Obstetricia No. 4, "Luis Castelazo Ayala", Instituto Mexicano del Seguro Social, Río Magdalena 289, Mezzanine, Colonia Tizapan San Ángel, Alcaldía Álvaro Obregón, C.P. 01090, Mexico City, Mexico
| | - Eunice López-Muñoz
- Medical Research Unit in Reproductive Medicine, Unidad Médica de Alta Especialidad, Hospital de Gineco Obstetricia No. 4, "Luis Castelazo Ayala", Instituto Mexicano del Seguro Social, Río Magdalena 289, Level 6, Laboratory K, Colonia Tizapan San Ángel, Alcaldía Álvaro Obregón, C.P. 01090, Mexico City, Mexico.
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30
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Tashiro S. Lessons from the Fukushima Daiichi nuclear power plant accident -from a research perspective. Ann ICRP 2021; 50:138-146. [PMID: 34109803 DOI: 10.1177/01466453211015394] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Since the accident at Fukushima Daiichi nuclear power plant, there has been a focus on the impact of low-dose radiation exposure due to nuclear disasters and radiology on human bodies. In order to study very low levels of impact on the human body from low-dose radiation exposure, a system with high detection sensitivity is needed. Until now, the most well-established biological radiation effect detection system in the field of emergency radiation medicine has been chromosomal analysis. However, chromosomal analysis requires advanced skills, and it is necessary to perform chromosomal analysis of a large number of cells in order to detect slight effects on the human body due to low-dose radiation exposure. Therefore, in order to study the effects of low-dose radiation exposure on the human body, it is necessary to develop high-throughput chromosome analysis technology. We have established the PNA-FISH method, which is a fluorescence in-situ hybridisation method using a PNA probe, as a high-throughput chromosome analysis technique. Using this method, the detection of dicentrics and ring chromosomes has become very efficient. Using this technology, chromosomal analysis was performed on peripheral blood before and after computed tomography (CT) examination of patients at Hiroshima University Hospital, and it was possible to detect chromosomal abnormalities due to low-dose radiation exposure in the CT examination. Furthermore, it was shown that there may be individual differences in the increase in chromosomal abnormalities due to low-dose radiation exposure, suggesting the need to build a next-generation medical radiation exposure management system based on individual differences in radiation sensitivity. If techniques such as chromosomal analysis, which have been used for biological dose evaluation in emergency radiation medicine, can be used for general radiology, such as radiodiagnosis and treatment, that will be a contribution to radiology from an unprecedented angle. This article will discuss the clinical application of new biological dose evaluation methods that have been developed in the field of emergency radiation medicine.
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Affiliation(s)
- Satoshi Tashiro
- Department of Cellular Biology, Research Institute for Radiation Biology and Medicine, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima City 734-8553, Japan; e-mail:
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31
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Kivanc D, Dasdemir S. The relationship between defects in DNA repair genes and autoinflammatory diseases. Rheumatol Int 2021; 42:1-13. [PMID: 34091703 DOI: 10.1007/s00296-021-04906-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Accepted: 05/29/2021] [Indexed: 01/11/2023]
Abstract
Tissue inflammation and damage with the abnormal and overactivation of innate immune system results with the development of a hereditary disease group of autoinflammatory diseases. Multiple numbers of DNA damage develop with the continuous exposure to endogenous and exogenous genotoxic effects, and these damages are repaired through the DNA damage response governed by the genes involved in the DNA repair mechanisms, and proteins of these genes. Studies showed that DNA damage might trigger the innate immune response through nuclear DNA accumulation in the cytoplasm, and through chronic DNA damage response which signals itself and/or by micronucleus. The aim of the present review is to identify the effect of mutation that occurred in DNA repair genes on development of DNA damage response and autoinflammatory diseases.
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Affiliation(s)
- Demet Kivanc
- Department of Medical Biology, Istanbul Faculty of Medicine, Istanbul University, Istanbul, Turkey
| | - Selcuk Dasdemir
- Department of Medical Biology, Istanbul Faculty of Medicine, Istanbul University, Istanbul, Turkey.
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32
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Jensen RB, Rothenberg E. Preserving genome integrity in human cells via DNA double-strand break repair. Mol Biol Cell 2021; 31:859-865. [PMID: 32286930 PMCID: PMC7185975 DOI: 10.1091/mbc.e18-10-0668] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
The efficient maintenance of genome integrity in the face of cellular stress is vital to protect against human diseases such as cancer. DNA replication, chromatin dynamics, cellular signaling, nuclear architecture, cell cycle checkpoints, and other cellular activities contribute to the delicate spatiotemporal control that cells utilize to regulate and maintain genome stability. This perspective will highlight DNA double-strand break (DSB) repair pathways in human cells, how DNA repair failures can lead to human disease, and how PARP inhibitors have emerged as a novel clinical therapy to treat homologous recombination-deficient tumors. We briefly discuss how failures in DNA repair produce a permissive genetic environment in which preneoplastic cells evolve to reach their full tumorigenic potential. Finally, we conclude that an in-depth understanding of DNA DSB repair pathways in human cells will lead to novel therapeutic strategies to treat cancer and potentially other human diseases.
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Affiliation(s)
- Ryan B Jensen
- Department of Therapeutic Radiology, Yale University School of Medicine, New Haven, CT 06520-8040
| | - Eli Rothenberg
- Department of Biochemistry and Molecular Pharmacology, New York University School of Medicine, New York, NY 10016
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33
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Komulainen E, Badman J, Rey S, Rulten S, Ju L, Fennell K, Kalasova I, Ilievova K, McKinnon PJ, Hanzlikova H, Staras K, Caldecott KW. Parp1 hyperactivity couples DNA breaks to aberrant neuronal calcium signalling and lethal seizures. EMBO Rep 2021; 22:e51851. [PMID: 33932076 PMCID: PMC8097344 DOI: 10.15252/embr.202051851] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2020] [Revised: 03/04/2021] [Accepted: 03/05/2021] [Indexed: 12/21/2022] Open
Abstract
Defects in DNA single-strand break repair (SSBR) are linked with neurological dysfunction but the underlying mechanisms remain poorly understood. Here, we show that hyperactivity of the DNA strand break sensor protein Parp1 in mice in which the central SSBR protein Xrcc1 is conditionally deleted (Xrcc1Nes-Cre ) results in lethal seizures and shortened lifespan. Using electrophysiological recording and synaptic imaging approaches, we demonstrate that aberrant Parp1 activation triggers seizure-like activity in Xrcc1-defective hippocampus ex vivo and deregulated presynaptic calcium signalling in isolated hippocampal neurons in vitro. Moreover, we show that these defects are prevented by Parp1 inhibition or deletion and, in the case of Parp1 deletion, that the lifespan of Xrcc1Nes-Cre mice is greatly extended. This is the first demonstration that lethal seizures can be triggered by aberrant Parp1 activity at unrepaired SSBs, highlighting PARP inhibition as a possible therapeutic approach in hereditary neurological disease.
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Affiliation(s)
- Emilia Komulainen
- Genome Damage and Stability CentreSchool of Life SciencesUniversity of SussexBrightonUK
| | - Jack Badman
- Genome Damage and Stability CentreSchool of Life SciencesUniversity of SussexBrightonUK
- Sussex NeuroscienceSchool of Life SciencesUniversity of SussexBrightonUK
| | - Stephanie Rey
- Sussex NeuroscienceSchool of Life SciencesUniversity of SussexBrightonUK
| | - Stuart Rulten
- Genome Damage and Stability CentreSchool of Life SciencesUniversity of SussexBrightonUK
| | - Limei Ju
- Genome Damage and Stability CentreSchool of Life SciencesUniversity of SussexBrightonUK
| | - Kate Fennell
- Sussex NeuroscienceSchool of Life SciencesUniversity of SussexBrightonUK
| | - Ilona Kalasova
- Department of Genome DynamicsInstitute of Molecular Genetics of the Czech Academy of SciencesPragueCzech Republic
| | - Kristyna Ilievova
- Department of Genome DynamicsInstitute of Molecular Genetics of the Czech Academy of SciencesPragueCzech Republic
| | - Peter J McKinnon
- Department of GeneticsSt Jude Children’s Research HospitalMemphisTNUSA
| | - Hana Hanzlikova
- Genome Damage and Stability CentreSchool of Life SciencesUniversity of SussexBrightonUK
- Department of Genome DynamicsInstitute of Molecular Genetics of the Czech Academy of SciencesPragueCzech Republic
| | - Kevin Staras
- Sussex NeuroscienceSchool of Life SciencesUniversity of SussexBrightonUK
| | - Keith W Caldecott
- Genome Damage and Stability CentreSchool of Life SciencesUniversity of SussexBrightonUK
- Department of Genome DynamicsInstitute of Molecular Genetics of the Czech Academy of SciencesPragueCzech Republic
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34
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Yamaguchi H, Kitami K, Wu X, He L, Wang J, Wang B, Komatsu Y. Alteration of DNA Damage Response Causes Cleft Palate. Front Physiol 2021; 12:649492. [PMID: 33854442 PMCID: PMC8039291 DOI: 10.3389/fphys.2021.649492] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2021] [Accepted: 03/08/2021] [Indexed: 12/13/2022] Open
Abstract
Cleft palate is one of the most common craniofacial birth defects, however, little is known about how changes in the DNA damage response (DDR) cause cleft palate. To determine the role of DDR during palatogenesis, the DDR process was altered using a pharmacological intervention approach. A compromised DDR caused by a poly (ADP-ribose) polymerase (PARP) enzyme inhibitor resulted in cleft palate in wild-type mouse embryos, with increased DNA damage and apoptosis. In addition, a mouse genetic approach was employed to disrupt breast cancer 1 (BRCA1) and breast cancer 2 (BRCA2), known as key players in DDR. An ectomesenchymal-specific deletion of Brca1 or Brca2 resulted in cleft palate due to attenuation of cell survival. This was supported by the phenotypes of the ectomesenchymal-specific Brca1/Brca2 double-knockout mice. The cleft palate phenotype was rescued by superimposing p53 null alleles, demonstrating that the BRCA1/2-p53 DDR pathway is critical for palatogenesis. Our study highlights the importance of DDR in palatogenesis.
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Affiliation(s)
- Hiroyuki Yamaguchi
- Department of Pediatrics, The University of Texas Medical School at Houston, Houston, TX, United States
| | - Kohei Kitami
- Department of Pediatrics, The University of Texas Medical School at Houston, Houston, TX, United States
| | - Xiao Wu
- Department of Genetics, The University of Texas MD Anderson Cancer Center, Houston, TX, United States
| | - Li He
- Department of Pediatrics, The University of Texas Medical School at Houston, Houston, TX, United States
| | - Jianbo Wang
- Department of Pediatrics, The University of Texas Medical School at Houston, Houston, TX, United States
| | - Bin Wang
- Department of Genetics, The University of Texas MD Anderson Cancer Center, Houston, TX, United States.,Graduate Program in Genetics & Epigenetics, The University of Texas MD Anderson Cancer Center UTHealth Graduate School of Biomedical Sciences, Houston, TX, United States
| | - Yoshihiro Komatsu
- Department of Pediatrics, The University of Texas Medical School at Houston, Houston, TX, United States.,Graduate Program in Genetics & Epigenetics, The University of Texas MD Anderson Cancer Center UTHealth Graduate School of Biomedical Sciences, Houston, TX, United States
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35
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Apelt K, White SM, Kim HS, Yeo JE, Kragten A, Wondergem AP, Rooimans MA, González-Prieto R, Wiegant WW, Lunke S, Flanagan D, Pantaleo S, Quinlan C, Hardikar W, van Attikum H, Vertegaal AC, Wilson BT, Wolthuis RM, Schärer OD, Luijsterburg MS. ERCC1 mutations impede DNA damage repair and cause liver and kidney dysfunction in patients. J Exp Med 2021; 218:e20200622. [PMID: 33315086 PMCID: PMC7927433 DOI: 10.1084/jem.20200622] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2020] [Revised: 09/25/2020] [Accepted: 10/15/2020] [Indexed: 12/12/2022] Open
Abstract
ERCC1-XPF is a multifunctional endonuclease involved in nucleotide excision repair (NER), interstrand cross-link (ICL) repair, and DNA double-strand break (DSB) repair. Only two patients with bi-allelic ERCC1 mutations have been reported, both of whom had features of Cockayne syndrome and died in infancy. Here, we describe two siblings with bi-allelic ERCC1 mutations in their teenage years. Genomic sequencing identified a deletion and a missense variant (R156W) within ERCC1 that disrupts a salt bridge below the XPA-binding pocket. Patient-derived fibroblasts and knock-in epithelial cells carrying the R156W substitution show dramatically reduced protein levels of ERCC1 and XPF. Moreover, mutant ERCC1 weakly interacts with NER and ICL repair proteins, resulting in diminished recruitment to DNA damage. Consequently, patient cells show strongly reduced NER activity and increased chromosome breakage induced by DNA cross-linkers, while DSB repair was relatively normal. We report a new case of ERCC1 deficiency that severely affects NER and considerably impacts ICL repair, which together result in a unique phenotype combining short stature, photosensitivity, and progressive liver and kidney dysfunction.
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Affiliation(s)
- Katja Apelt
- Department of Human Genetics, Leiden University Medical Center, Leiden, Netherlands
| | - Susan M. White
- Victorian Clinical Genetics Services, Murdoch Children’s Research Institute, Parkville, Australia
- Department of Paediatrics, University of Melbourne, Parkville, Australia
| | - Hyun Suk Kim
- Center for Genomic Integrity, Institute for Basic Science, Ulsan, Republic of Korea
| | - Jung-Eun Yeo
- Center for Genomic Integrity, Institute for Basic Science, Ulsan, Republic of Korea
| | - Angela Kragten
- Department of Human Genetics, Leiden University Medical Center, Leiden, Netherlands
| | | | - Martin A. Rooimans
- Section of Oncogenetics, Department of Clinical Genetics, Vrije Universiteit Medical Center and Cancer Center Amsterdam, Amsterdam, Netherlands
| | - Román González-Prieto
- Department of Cell and Chemical Biology, Leiden University Medical Center, Leiden, Netherlands
| | - Wouter W. Wiegant
- Department of Human Genetics, Leiden University Medical Center, Leiden, Netherlands
| | - Sebastian Lunke
- Victorian Clinical Genetics Services, Murdoch Children’s Research Institute, Parkville, Australia
- Department of Pathology, University of Melbourne, Parkville, Australia
| | - Daniel Flanagan
- Victorian Clinical Genetics Services, Murdoch Children’s Research Institute, Parkville, Australia
| | - Sarah Pantaleo
- Victorian Clinical Genetics Services, Murdoch Children’s Research Institute, Parkville, Australia
| | - Catherine Quinlan
- Department of Paediatrics, University of Melbourne, Parkville, Australia
- Department of Nephrology, Royal Children’s Hospital, Melbourne, Australia
- Department of Kidney Regeneration, Murdoch Children’s Research Institute, Melbourne, Australia
| | - Winita Hardikar
- Department of Paediatrics, University of Melbourne, Parkville, Australia
- Department of Gastroenterology, Royal Children's Hospital, Melbourne, Victoria, Australia
- Murdoch Children’s Research Institute, Parkville, Australia
| | - Haico van Attikum
- Department of Human Genetics, Leiden University Medical Center, Leiden, Netherlands
| | - Alfred C.O. Vertegaal
- Department of Cell and Chemical Biology, Leiden University Medical Center, Leiden, Netherlands
| | - Brian T. Wilson
- Institute of Genetic Medicine, Newcastle University, International Centre for Life, Newcastle upon Tyne, UK
- Northern Genetics Service, Newcastle upon Tyne Hospitals National Health Service Foundation Trust, International Centre for Life, Newcastle upon Tyne, UK
- Department of Clinical Genetics, Great Ormond Street Hospital, London, UK
| | - Rob M.F. Wolthuis
- Section of Oncogenetics, Department of Clinical Genetics, Vrije Universiteit Medical Center and Cancer Center Amsterdam, Amsterdam, Netherlands
| | - Orlando D. Schärer
- Center for Genomic Integrity, Institute for Basic Science, Ulsan, Republic of Korea
- Department of Biological Sciences, School of Life Sciences, Ulsan National Institute of Science and Technology, Ulsan, Republic of Korea
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36
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Chowdhuri SP, Das BB. Top1-PARP1 association and beyond: from DNA topology to break repair. NAR Cancer 2021; 3:zcab003. [PMID: 33981998 PMCID: PMC8095074 DOI: 10.1093/narcan/zcab003] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2020] [Revised: 12/15/2020] [Accepted: 01/12/2021] [Indexed: 12/16/2022] Open
Abstract
Selective trapping of human topoisomerase 1 (Top1) on the DNA (Top1 cleavage complexes; Top1cc) by specific Top1-poisons triggers DNA breaks and cell death. Poly(ADP-ribose) polymerase 1 (PARP1) is an early nick sensor for trapped Top1cc. New mechanistic insights have been developed in recent years to rationalize the importance of PARP1 beyond the repair of Top1-induced DNA breaks. This review summarizes the progress in the molecular mechanisms of trapped Top1cc-induced DNA damage, PARP1 activation at DNA damage sites, PAR-dependent regulation of Top1 nuclear dynamics, and PARP1-associated molecular network for Top1cc repair. Finally, we have discussed the rationale behind the synergy between the combination of Top1 poison and PARP inhibitors in cancer chemotherapies, which is independent of the ‘PARP trapping’ phenomenon.
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Affiliation(s)
- Srijita Paul Chowdhuri
- Laboratory of Molecular Biology, School of Biological Sciences, Indian Association for the Cultivation of Science, 2A & B, Raja S. C. Mullick Road, Jadavpur, Kolkata 700032, India
| | - Benu Brata Das
- Laboratory of Molecular Biology, School of Biological Sciences, Indian Association for the Cultivation of Science, 2A & B, Raja S. C. Mullick Road, Jadavpur, Kolkata 700032, India
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37
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Manjunath M, Choudhary B, Raghavan SC. SCR7, a potent cancer therapeutic agent and a biochemical inhibitor of nonhomologous DNA end-joining. Cancer Rep (Hoboken) 2021; 4:e1341. [PMID: 33496064 PMCID: PMC8222562 DOI: 10.1002/cnr2.1341] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Revised: 12/15/2020] [Accepted: 12/21/2020] [Indexed: 12/11/2022] Open
Abstract
Background DNA double‐strand breaks (DSBs) are harmful to the cell as it could lead to genomic instability and cell death when left unrepaired. Homologous recombination and nonhomologous end‐joining (NHEJ) are two major DSB repair pathways, responsible for ensuring genome integrity in mammals. There have been multiple efforts using small molecule inhibitors to target these DNA repair pathways in cancers. SCR7 is a very well‐studied anticancer molecule that blocks NHEJ by targeting one of the critical enzymes, Ligase IV. Recent findings In this review, we have highlighted the anticancer effects of SCR7 as a single agent and in combination with other chemotherapeutic agents and radiation. SCR7 blocked NHEJ effectively both in vitro and ex vivo. SCR7 has been used for biochemical studies like chromosomal territory resetting and in understanding the role of repair proteins in cell cycle phases. Various forms of SCR7 and its derivatives are discussed. SCR7 is also used as a potent biochemical inhibitor of NHEJ, which has found its application in improving genome editing using a CRISPR‐Cas system. Conclusion SCR7 is a potent NHEJ inhibitor with unique properties and wide applications as an anticancer agent. Most importantly, SCR7 has become a handy aid for improving genome editing across different model systems.
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Affiliation(s)
- Meghana Manjunath
- Institute of Bioinformatics and Applied Biotechnology, Bangalore, India.,Manipal Academy of Higher Education, Manipal, India
| | - Bibha Choudhary
- Institute of Bioinformatics and Applied Biotechnology, Bangalore, India
| | - Sathees C Raghavan
- Department of Biochemistry, Indian Institute of Science, Bangalore, India
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38
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Signaling pathways involved in cell cycle arrest during the DNA breaks. DNA Repair (Amst) 2021; 98:103047. [PMID: 33454524 DOI: 10.1016/j.dnarep.2021.103047] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2021] [Accepted: 01/04/2021] [Indexed: 12/12/2022]
Abstract
Our genome bears tens of thousands of harms and devastations per day; In this regard, numerous sophisticated and complicated mechanisms are embedded by our cells in furtherance of remitting an unchanged and stable genome to their next generation. These mechanisms, that are collectively called DDR, have the duty of detecting the lesions and repairing them. it's necessary for the viability of any living cell that sustain the integrity and stability of its genetic content and this highlights the role of mediators that transduce the signals of DNA damage to the cell cycle in order to prevent the replication of a defective DNA. In this paper, we review the signaling pathways that lie between these processes and define how different ingredients of DDR are also able to affect the checkpoint signaling.
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39
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Inhibitors of DNA double-strand break repair at the crossroads of cancer therapy and genome editing. Biochem Pharmacol 2020; 182:114195. [DOI: 10.1016/j.bcp.2020.114195] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2020] [Revised: 08/03/2020] [Accepted: 08/10/2020] [Indexed: 12/17/2022]
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40
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The FHA domain of PNKP is essential for its recruitment to DNA damage sites and maintenance of genome stability. Mutat Res 2020; 822:111727. [PMID: 33220551 DOI: 10.1016/j.mrfmmm.2020.111727] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2020] [Revised: 09/28/2020] [Accepted: 10/26/2020] [Indexed: 01/08/2023]
Abstract
Polynucleotide kinase phosphatase (PNKP) has dual enzymatic activities as kinase and phosphatase for DNA ends, which are the prerequisite for the ligation, and thus is involved in base excision repair, single-strand break repair and non-homologous end joining for double-strand break (DSB) repair. In this study, we examined mechanisms for the recruitment of PNKP to DNA damage sites by laser micro-irradiation and live-cell imaging analysis using confocal microscope. We show that the forkhead-associated (FHA) domain of PNKP is essential for the recruitment of PNKP to DNA damage sites. Arg35 and Arg48 within the FHA domain are required for interactions with XRCC1 and XRCC4. PNKP R35A/R48A mutant failed to accumulate on the laser track and siRNA-mediated depletion of XRCC1 and/or XRCC4 reduced PNKP accumulation on the laser track, indicating that PNKP is recruited to DNA damage sites via the interactions between its FHA domain and XRCC1 or XRCC4. Furthermore, cells expressing PNKP R35A/R48A mutant exhibited increased sensitivity toward ionizing radiation in association with delayed SSB and DSB repair and genome instability, represented by micronuclei and chromosome bridges. Taken together, these findings revealed the importance of PNKP recruitment to DNA damage sites via its FHA domain for DNA repair and maintenance of genome stability.
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41
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Bouwman BAM, Agostini F, Garnerone S, Petrosino G, Gothe HJ, Sayols S, Moor AE, Itzkovitz S, Bienko M, Roukos V, Crosetto N. Genome-wide detection of DNA double-strand breaks by in-suspension BLISS. Nat Protoc 2020; 15:3894-3941. [PMID: 33139954 DOI: 10.1038/s41596-020-0397-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2020] [Accepted: 08/04/2020] [Indexed: 02/07/2023]
Abstract
sBLISS (in-suspension breaks labeling in situ and sequencing) is a versatile and widely applicable method for identification of endogenous and induced DNA double-strand breaks (DSBs) in any cell type that can be brought into suspension. sBLISS provides genome-wide profiles of the most consequential DNA lesion implicated in a variety of pathological, but also physiological, processes. In sBLISS, after in situ labeling, DSB ends are linearly amplified, followed by next-generation sequencing and DSB landscape analysis. Here, we present a step-by-step experimental protocol for sBLISS, as well as a basic computational analysis. The main advantages of sBLISS are (i) the suspension setup, which renders the protocol user-friendly and easily scalable; (ii) the possibility of adapting it to a high-throughput or single-cell workflow; and (iii) its flexibility and its applicability to virtually every cell type, including patient-derived cells, organoids, and isolated nuclei. The wet-lab protocol can be completed in 1.5 weeks and is suitable for researchers with intermediate expertise in molecular biology and genomics. For the computational analyses, basic-to-intermediate bioinformatics expertise is required.
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Affiliation(s)
- Britta A M Bouwman
- Science for Life Laboratory, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden.
| | - Federico Agostini
- Science for Life Laboratory, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
| | - Silvano Garnerone
- Science for Life Laboratory, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
| | | | | | - Sergi Sayols
- Institute of Molecular Biology (IMB), Mainz, Germany
| | - Andreas E Moor
- Department of Biosystems Science and Engineering, ETH Zürich, Basel, Switzerland
| | - Shalev Itzkovitz
- Department of Molecular Cell Biology, Weizmann Institute of Science, Rehovot, Israel
| | - Magda Bienko
- Science for Life Laboratory, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
| | | | - Nicola Crosetto
- Science for Life Laboratory, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden.
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Castañeda-Zegarra S, Fernandez-Berrocal M, Tkachov M, Yao R, Upfold NLE, Oksenych V. Genetic interaction between the non-homologous end-joining factors during B and T lymphocyte development: In vivo mouse models. Scand J Immunol 2020; 92:e12936. [PMID: 32654175 DOI: 10.1111/sji.12936] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2020] [Revised: 06/07/2020] [Accepted: 07/06/2020] [Indexed: 12/16/2022]
Abstract
Non-homologous end joining (NHEJ) is the main DNA repair mechanism for the repair of double-strand breaks (DSBs) throughout the course of the cell cycle. DSBs are generated in developing B and T lymphocytes during V(D)J recombination to increase the repertoire of B and T cell receptors. DSBs are also generated during the class switch recombination (CSR) process in mature B lymphocytes, providing distinct effector functions of antibody heavy chain constant regions. Thus, NHEJ is important for both V(D)J recombination and CSR. NHEJ comprises core Ku70 and Ku80 subunits that form the Ku heterodimer, which binds DSBs and promotes the recruitment of accessory factors (e.g., DNA-PKcs, Artemis, PAXX, MRI) and downstream core factors (XLF, Lig4 and XRCC4). In recent decades, new NHEJ proteins have been reported, increasing complexity of this molecular pathway. Numerous in vivo mouse models have been generated and characterized to identify the interplay of NHEJ factors and their role in development of adaptive immune system. This review summarizes the currently available mouse models lacking one or several NHEJ factors, with a particular focus on early B cell development. We also underline genetic interactions and redundancy in the NHEJ pathway in mice.
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Affiliation(s)
- Sergio Castañeda-Zegarra
- Department of Clinical and Molecular Medicine (IKOM), Norwegian University of Science and Technology, Trondheim, Norway.,St. Olavs Hospital, Clinic of Medicine, Trondheim University Hospital, Trondheim, Norway
| | - Marion Fernandez-Berrocal
- Department of Clinical and Molecular Medicine (IKOM), Norwegian University of Science and Technology, Trondheim, Norway.,St. Olavs Hospital, Clinic of Medicine, Trondheim University Hospital, Trondheim, Norway.,Behavioural Neurobiology MS Program, Theodor-Boveri-Institute, Biocenter, University of Würzburg, Würzburg, Germany
| | - Max Tkachov
- Department of Clinical and Molecular Medicine (IKOM), Norwegian University of Science and Technology, Trondheim, Norway.,St. Olavs Hospital, Clinic of Medicine, Trondheim University Hospital, Trondheim, Norway
| | - Rouan Yao
- Department of Clinical and Molecular Medicine (IKOM), Norwegian University of Science and Technology, Trondheim, Norway.,St. Olavs Hospital, Clinic of Medicine, Trondheim University Hospital, Trondheim, Norway
| | - Nikki Lyn Esnardo Upfold
- Department of Clinical and Molecular Medicine (IKOM), Norwegian University of Science and Technology, Trondheim, Norway.,St. Olavs Hospital, Clinic of Medicine, Trondheim University Hospital, Trondheim, Norway
| | - Valentyn Oksenych
- Department of Clinical and Molecular Medicine (IKOM), Norwegian University of Science and Technology, Trondheim, Norway.,St. Olavs Hospital, Clinic of Medicine, Trondheim University Hospital, Trondheim, Norway.,Department of Biosciences and Nutrition (BioNut), Karolinska Institutet, Huddinge, Sweden.,Department of Clinical Medicine, Faculty of Health Sciences, UiT-The Arctic University of Norway, Tromsø, Norway
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43
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Alhmoud JF, Mustafa AG, Malki MI. Targeting DNA Repair Pathways in Hematological Malignancies. Int J Mol Sci 2020; 21:ijms21197365. [PMID: 33036137 PMCID: PMC7582413 DOI: 10.3390/ijms21197365] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2020] [Revised: 09/25/2020] [Accepted: 10/01/2020] [Indexed: 12/19/2022] Open
Abstract
DNA repair plays an essential role in protecting cells that are repeatedly exposed to endogenous or exogenous insults that can induce varying degrees of DNA damage. Any defect in DNA repair mechanisms results in multiple genomic changes that ultimately may result in mutation, tumor growth, and/or cell apoptosis. Furthermore, impaired repair mechanisms can also lead to genomic instability, which can initiate tumorigenesis and development of hematological malignancy. This review discusses recent findings and highlights the importance of DNA repair components and the impact of their aberrations on hematological malignancies.
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Affiliation(s)
- Jehad F. Alhmoud
- Department of Medical Laboratory Sciences, Faculty of Applied Medical Sciences, Al-Ahliyya Amman University, Amman 19328, Jordan;
| | - Ayman G. Mustafa
- College of Medicine, QU Health, Qatar University, P. O. Box 2713 Doha, Qatar;
| | - Mohammed Imad Malki
- College of Medicine, QU Health, Qatar University, P. O. Box 2713 Doha, Qatar;
- Correspondence: ; Tel.: +97-44403-7847
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44
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Systematic Surveys of Iron Homeostasis Mechanisms Reveal Ferritin Superfamily and Nucleotide Surveillance Regulation to be Modified by PINK1 Absence. Cells 2020; 9:cells9102229. [PMID: 33023155 PMCID: PMC7650593 DOI: 10.3390/cells9102229] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2020] [Revised: 09/21/2020] [Accepted: 09/29/2020] [Indexed: 12/13/2022] Open
Abstract
Iron deprivation activates mitophagy and extends lifespan in nematodes. In patients suffering from Parkinson’s disease (PD), PINK1-PRKN mutations via deficient mitophagy trigger iron accumulation and reduce lifespan. To evaluate molecular effects of iron chelator drugs as a potential PD therapy, we assessed fibroblasts by global proteome profiles and targeted transcript analyses. In mouse cells, iron shortage decreased protein abundance for iron-binding nucleotide metabolism enzymes (prominently XDH and ferritin homolog RRM2). It also decreased the expression of factors with a role for nucleotide surveillance, which associate with iron-sulfur-clusters (ISC), and are important for growth and survival. This widespread effect included prominently Nthl1-Ppat-Bdh2, but also mitochondrial Glrx5-Nfu1-Bola1, cytosolic Aco1-Abce1-Tyw5, and nuclear Dna2-Elp3-Pold1-Prim2. Incidentally, upregulated Pink1-Prkn levels explained mitophagy induction, the downregulated expression of Slc25a28 suggested it to function in iron export. The impact of PINK1 mutations in mouse and patient cells was pronounced only after iron overload, causing hyperreactive expression of ribosomal surveillance factor Abce1 and of ferritin, despite ferritin translation being repressed by IRP1. This misregulation might be explained by the deficiency of the ISC-biogenesis factor GLRX5. Our systematic survey suggests mitochondrial ISC-biogenesis and post-transcriptional iron regulation to be important in the decision, whether organisms undergo PD pathogenesis or healthy aging.
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45
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Kalasova I, Hailstone R, Bublitz J, Bogantes J, Hofmann W, Leal A, Hanzlikova H, Caldecott KW. Pathological mutations in PNKP trigger defects in DNA single-strand break repair but not DNA double-strand break repair. Nucleic Acids Res 2020; 48:6672-6684. [PMID: 32504494 PMCID: PMC7337934 DOI: 10.1093/nar/gkaa489] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2020] [Revised: 04/30/2020] [Accepted: 06/04/2020] [Indexed: 12/20/2022] Open
Abstract
Hereditary mutations in polynucleotide kinase-phosphatase (PNKP) result in a spectrum of neurological pathologies ranging from neurodevelopmental dysfunction in microcephaly with early onset seizures (MCSZ) to neurodegeneration in ataxia oculomotor apraxia-4 (AOA4) and Charcot-Marie-Tooth disease (CMT2B2). Consistent with this, PNKP is implicated in the repair of both DNA single-strand breaks (SSBs) and DNA double-strand breaks (DSBs); lesions that can trigger neurodegeneration and neurodevelopmental dysfunction, respectively. Surprisingly, however, we did not detect a significant defect in DSB repair (DSBR) in primary fibroblasts from PNKP patients spanning the spectrum of PNKP-mutated pathologies. In contrast, the rate of SSB repair (SSBR) is markedly reduced. Moreover, we show that the restoration of SSBR in patient fibroblasts collectively requires both the DNA kinase and DNA phosphatase activities of PNKP, and the fork-head associated (FHA) domain that interacts with the SSBR protein, XRCC1. Notably, however, the two enzymatic activities of PNKP appear to affect different aspects of disease pathology, with reduced DNA phosphatase activity correlating with neurodevelopmental dysfunction and reduced DNA kinase activity correlating with neurodegeneration. In summary, these data implicate reduced rates of SSBR, not DSBR, as the source of both neurodevelopmental and neurodegenerative pathology in PNKP-mutated disease, and the extent and nature of this reduction as the primary determinant of disease severity.
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Affiliation(s)
- Ilona Kalasova
- Department of Genome Dynamics, Institute of Molecular Genetics of the Czech Academy of Sciences, Prague 4, 142 20, Czech Republic
| | - Richard Hailstone
- Genome Damage and Stability Centre, University of Sussex, Falmer, Brighton BN1 9RQ, UK
| | - Janin Bublitz
- Department of Human Genetics, Hannover Medical School, Hannover, Germany
| | - Jovel Bogantes
- Servicio de Cirugía Reconstructiva, Hospital Rafael Ángel Calderón Guardia, Caja Costarricense de Seguro Social, San José, Costa Rica
| | - Winfried Hofmann
- Department of Human Genetics, Hannover Medical School, Hannover, Germany
| | - Alejandro Leal
- Section of Genetics and Biotechnology, School of Biology, University of Costa Rica, San José, Costa Rica
| | - Hana Hanzlikova
- Department of Genome Dynamics, Institute of Molecular Genetics of the Czech Academy of Sciences, Prague 4, 142 20, Czech Republic.,Genome Damage and Stability Centre, University of Sussex, Falmer, Brighton BN1 9RQ, UK
| | - Keith W Caldecott
- Department of Genome Dynamics, Institute of Molecular Genetics of the Czech Academy of Sciences, Prague 4, 142 20, Czech Republic.,Genome Damage and Stability Centre, University of Sussex, Falmer, Brighton BN1 9RQ, UK
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46
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Smits VAJ, Alonso-de Vega I, Warmerdam DO. Chromatin regulators and their impact on DNA repair and G2 checkpoint recovery. Cell Cycle 2020; 19:2083-2093. [PMID: 32730133 DOI: 10.1080/15384101.2020.1796037] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
Abstract
Chromatin plays a pivotal role in regulating the DNA damage response and during DNA double-strand break repair. Upon the generation of DNA breaks, the chromatin structure is altered by post-translational modifications of histones and chromatin remodeling. How the chromatin structure, and the epigenetic information that it carries, is reestablished after the completion of DNA break repair remains unclear though. Also, how these processes influence recovery of the cell cycle remains poorly understood. We recently performed a reverse genetic screen for novel chromatin regulators that control checkpoint recovery after DNA damage. Here we discuss the implications of PHD finger protein 6 (PHF6) and additional candidates from the NuA4 ATPase-dependent chromatin-remodeling complex and the Cohesin complex, required for sister chromatid cohesion, in DNA repair and checkpoint recovery in more detail. In addition, the potential role of this novel function of PHF6 in cancer development and treatment is reviewed.
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Affiliation(s)
- Veronique A J Smits
- Unidad de Investigación, Hospital Universitario de Canarias , La Laguna, Spain.,Instituto de Tecnologías Biomédicas, Universidad de La Laguna , Tenerife, Spain.,Universidad Fernando Pessoa Canarias , Las Palmas de Gran Canaria, Spain
| | - Ignacio Alonso-de Vega
- Unidad de Investigación, Hospital Universitario de Canarias , La Laguna, Spain.,Instituto de Tecnologías Biomédicas, Universidad de La Laguna , Tenerife, Spain
| | - Daniël O Warmerdam
- CRISPR Platform, Cancer Center Amsterdam, Amsterdam UMC, University of Amsterdam , Amsterdam, The Netherlands
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47
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De Mattia E, Roncato R, Palazzari E, Toffoli G, Cecchin E. Germline and Somatic Pharmacogenomics to Refine Rectal Cancer Patients Selection for Neo-Adjuvant Chemoradiotherapy. Front Pharmacol 2020; 11:897. [PMID: 32625092 PMCID: PMC7311751 DOI: 10.3389/fphar.2020.00897] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Accepted: 06/02/2020] [Indexed: 12/25/2022] Open
Abstract
Neoadjuvant chemoradiotherapy (nCRT) followed by radical surgery is the standard of care for patients with Locally Advanced Rectal Cancer (LARC). Current selection for nCRT is based on clinical criteria regardless of any molecular marker. Pharmacogenomics may be a useful strategy to personalize and optimize nCRT in LARC. This review aims to summarize the most recent and relevant findings about the role of germline and somatic pharmacogenomics in the prediction of nCRT outcome in patients with LARC, discussing the state of the art of their application in the clinical practice. A systematic literature search of the PubMed database was completed to identify relevant English-language papers published up to January 2020. The chemotherapeutic backbone of nCRT is represented by fluoropyrimidines, mainly metabolized by DPD (Dihydro-Pyrimidine Dehydrogenase, DPYD). The clinical impact of testing DPYD*2A, DPYD*13, c.2846A > T and c.1236G > A-HapB3 before a fluoropyrimidines administration to increase treatment safety is widely acknowledged. Other relevant target genes are TYMS (Thymidylate Synthase) and MTHFR (Methylene-Tetrahydro-Folate Reductase), whose polymorphisms were mainly studied as potential markers of treatment efficacy in LARC. A pivotal role of a TYMS polymorphism in the gene promoter region (rs34743033) was reported and was pioneeringly used to guide nCRT treatment in a phase II study. The pharmacogenomic analysis of other pathways mostly involved in the cellular response to radiation damage, as the DNA repair and the activation of the inflammatory cascade, provided less consistent results. A high rate of somatic mutation in genes belonging to PI3K (Phosphatidyl-Inositol 3-Kinase) and MAPK (Mitogen-Activated Protein Kinase) pathways, as BRAF (V-raf murine sarcoma viral oncogene homolog B1), KRAS (Kirsten Rat Sarcoma viral oncogene homolog), NRAS (Neuroblastoma RAS viral (v-ras) oncogene homolog), PIK3CA (Phosphatidyl-Inositol-4,5-bisphosphate 3-Kinase, Catalytic Subunit Alpha), as well as TP53 (Tumor Protein 53) was reported in LARC. Their pharmacogenomic role, already defined in colorectal cancer, is under investigation in LARC with promising results concerning specific somatic mutations in KRAS and TP53, as predictors of tumor response and prognosis. The availability of circulating tumor DNA in plasma may also represent an opportunity to monitor somatic mutations in course of therapy.
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Affiliation(s)
- Elena De Mattia
- Clinical and Experimental Pharmacology, Centro di Riferimento Oncologico di Aviano (CRO), IRCCS, Aviano, Italy
| | - Rossana Roncato
- Clinical and Experimental Pharmacology, Centro di Riferimento Oncologico di Aviano (CRO), IRCCS, Aviano, Italy
| | - Elisa Palazzari
- Radiation Oncology, Centro di Riferimento Oncologico di Aviano (CRO) IRCCS, Aviano, Italy
| | - Giuseppe Toffoli
- Clinical and Experimental Pharmacology, Centro di Riferimento Oncologico di Aviano (CRO), IRCCS, Aviano, Italy
| | - Erika Cecchin
- Clinical and Experimental Pharmacology, Centro di Riferimento Oncologico di Aviano (CRO), IRCCS, Aviano, Italy
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48
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Kim J, Kim K, Mo JS, Lee Y. Atm deficiency in the DNA polymerase β null cerebellum results in cerebellar ataxia and Itpr1 reduction associated with alteration of cytosine methylation. Nucleic Acids Res 2020; 48:3678-3691. [PMID: 32123907 PMCID: PMC7144915 DOI: 10.1093/nar/gkaa140] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2019] [Revised: 02/20/2020] [Accepted: 02/27/2020] [Indexed: 12/13/2022] Open
Abstract
Genomic instability resulting from defective DNA damage responses or repair causes several abnormalities, including progressive cerebellar ataxia, for which the molecular mechanisms are not well understood. Here, we report a new murine model of cerebellar ataxia resulting from concomitant inactivation of POLB and ATM. POLB is one of key enzymes for the repair of damaged or chemically modified bases, including methylated cytosine, but selective inactivation of Polb during neurogenesis affects only a subpopulation of cortical interneurons despite the accumulation of DNA damage throughout the brain. However, dual inactivation of Polb and Atm resulted in ataxia without significant neuropathological defects in the cerebellum. ATM is a protein kinase that responds to DNA strand breaks, and mutations in ATM are responsible for Ataxia Telangiectasia, which is characterized by progressive cerebellar ataxia. In the cerebella of mice deficient for both Polb and Atm, the most downregulated gene was Itpr1, likely because of misregulated DNA methylation cycle. ITPR1 is known to mediate calcium homeostasis, and ITPR1 mutations result in genetic diseases with cerebellar ataxia. Our data suggest that dysregulation of ITPR1 in the cerebellum could be one of contributing factors to progressive ataxia observed in human genomic instability syndromes.
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Affiliation(s)
- Jusik Kim
- Genomic Instability Research Center, Ajou University School of Medicine, Suwon 16499, Korea.,Department of Biomedical Sciences, The Graduate School of Ajou University, Suwon 16499, Korea
| | - Keeeun Kim
- Genomic Instability Research Center, Ajou University School of Medicine, Suwon 16499, Korea.,Department of Biomedical Sciences, The Graduate School of Ajou University, Suwon 16499, Korea
| | - Jung-Soon Mo
- Genomic Instability Research Center, Ajou University School of Medicine, Suwon 16499, Korea.,Department of Biomedical Sciences, The Graduate School of Ajou University, Suwon 16499, Korea
| | - Youngsoo Lee
- Genomic Instability Research Center, Ajou University School of Medicine, Suwon 16499, Korea.,Department of Biomedical Sciences, The Graduate School of Ajou University, Suwon 16499, Korea
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49
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Distinct roles of XRCC1 in genome integrity in Xenopus egg extracts. Biochem J 2020; 476:3791-3804. [PMID: 31808793 DOI: 10.1042/bcj20190798] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2019] [Revised: 12/04/2019] [Accepted: 12/06/2019] [Indexed: 02/06/2023]
Abstract
Oxidative DNA damage represents one of the most abundant DNA lesions. It remains unclear how DNA repair and DNA damage response (DDR) pathways are co-ordinated and regulated following oxidative stress. While XRCC1 has been implicated in DNA repair, it remains unknown how exactly oxidative DNA damage is repaired and sensed by XRCC1. In this communication, we have demonstrated evidence that XRCC1 is dispensable for ATR-Chk1 DDR pathway following oxidative stress in Xenopus egg extracts. Whereas APE2 is essential for SSB repair, XRCC1 is not required for the repair of defined SSB and gapped plasmids with a 5'-OH or 5'-P terminus, suggesting that XRCC1 and APE2 may contribute to SSB repair via different mechanisms. Neither Polymerase beta nor Polymerase alpha is important for the repair of defined SSB structure. Nonetheless, XRCC1 is important for the repair of DNA damage following oxidative stress. Our observations suggest distinct roles of XRCC1 for genome integrity in oxidative stress in Xenopus egg extracts.
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50
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Lin Y, Raj J, Li J, Ha A, Hossain MA, Richardson C, Mukherjee P, Yan S. APE1 senses DNA single-strand breaks for repair and signaling. Nucleic Acids Res 2020; 48:1925-1940. [PMID: 31828326 PMCID: PMC7038996 DOI: 10.1093/nar/gkz1175] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2019] [Revised: 12/02/2019] [Accepted: 12/05/2019] [Indexed: 02/06/2023] Open
Abstract
DNA single-strand breaks (SSBs) represent the most abundant type of DNA damage. Unrepaired SSBs impair DNA replication and transcription, leading to cancer and neurodegenerative disorders. Although PARP1 and XRCC1 are implicated in the SSB repair pathway, it remains unclear how SSB repair and SSB signaling pathways are coordinated and regulated. Using Xenopus egg extract and in vitro reconstitution systems, here we show that SSBs are first sensed by APE1 to initiate 3'-5' SSB end resection, followed by APE2 recruitment to continue SSB end resection. Notably, APE1's exonuclease activity is critical for SSB repair and SSB signaling pathways. An APE1 exonuclease-deficient mutant identified in somatic tissue from a cancer patient highlighted the significance of APE1 exonuclease activity in cancer etiology. In addition, APE1 interacts with APE2 and PCNA, although PCNA is dispensable for APE1's exonuclease activity. Taken together, we propose a two-step APE1/APE2-mediated mechanism for SSB end resection that couples DNA damage response with SSB repair in a eukaryotic system.
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Affiliation(s)
- Yunfeng Lin
- Department of Biological Sciences, University of North Carolina at Charlotte, Charlotte, NC 28223, USA
| | - Jude Raj
- Department of Biological Sciences, University of North Carolina at Charlotte, Charlotte, NC 28223, USA
| | - Jia Li
- Department of Biological Sciences, University of North Carolina at Charlotte, Charlotte, NC 28223, USA
| | - Anh Ha
- Department of Biological Sciences, University of North Carolina at Charlotte, Charlotte, NC 28223, USA
| | - Md Akram Hossain
- Department of Biological Sciences, University of North Carolina at Charlotte, Charlotte, NC 28223, USA
| | - Christine Richardson
- Department of Biological Sciences, University of North Carolina at Charlotte, Charlotte, NC 28223, USA
| | - Pinku Mukherjee
- Department of Biological Sciences, University of North Carolina at Charlotte, Charlotte, NC 28223, USA
| | - Shan Yan
- Department of Biological Sciences, University of North Carolina at Charlotte, Charlotte, NC 28223, USA
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