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Ribeiro JH, Altinisik N, Rajan N, Verslegers M, Baatout S, Gopalakrishnan J, Quintens R. DNA damage and repair: underlying mechanisms leading to microcephaly. Front Cell Dev Biol 2023; 11:1268565. [PMID: 37881689 PMCID: PMC10597653 DOI: 10.3389/fcell.2023.1268565] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Accepted: 09/25/2023] [Indexed: 10/27/2023] Open
Abstract
DNA-damaging agents and endogenous DNA damage constantly harm genome integrity. Under genotoxic stress conditions, the DNA damage response (DDR) machinery is crucial in repairing lesions and preventing mutations in the basic structure of the DNA. Different repair pathways are implicated in the resolution of such lesions. For instance, the non-homologous DNA end joining and homologous recombination pathways are central cellular mechanisms by which eukaryotic cells maintain genome integrity. However, defects in these pathways are often associated with neurological disorders, indicating the pivotal role of DDR in normal brain development. Moreover, the brain is the most sensitive organ affected by DNA-damaging agents compared to other tissues during the prenatal period. The accumulation of lesions is believed to induce cell death, reduce proliferation and premature differentiation of neural stem and progenitor cells, and reduce brain size (microcephaly). Microcephaly is mainly caused by genetic mutations, especially genes encoding proteins involved in centrosomes and DNA repair pathways. However, it can also be induced by exposure to ionizing radiation and intrauterine infections such as the Zika virus. This review explains mammalian cortical development and the major DNA repair pathways that may lead to microcephaly when impaired. Next, we discuss the mechanisms and possible exposures leading to DNA damage and p53 hyperactivation culminating in microcephaly.
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Affiliation(s)
- Jessica Honorato Ribeiro
- Radiobiology Unit, Belgian Nuclear Research Centre (SCK CEN), Mol, Belgium
- Faculty of Bioscience Engineering, Ghent University, Ghent, Belgium
| | - Nazlican Altinisik
- Laboratory for Centrosome and Cytoskeleton Biology, Institute of Human Genetics, University Hospital, Heinrich-Heine-Universität, Düsseldorf, Germany
| | - Nicholas Rajan
- Radiobiology Unit, Belgian Nuclear Research Centre (SCK CEN), Mol, Belgium
| | - Mieke Verslegers
- Radiobiology Unit, Belgian Nuclear Research Centre (SCK CEN), Mol, Belgium
| | - Sarah Baatout
- Radiobiology Unit, Belgian Nuclear Research Centre (SCK CEN), Mol, Belgium
- Faculty of Bioscience Engineering, Ghent University, Ghent, Belgium
| | - Jay Gopalakrishnan
- Laboratory for Centrosome and Cytoskeleton Biology, Institute of Human Genetics, University Hospital, Heinrich-Heine-Universität, Düsseldorf, Germany
| | - Roel Quintens
- Radiobiology Unit, Belgian Nuclear Research Centre (SCK CEN), Mol, Belgium
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Yoo JY, Lee YJ, Kim YJ, Baik TK, Lee JH, Lee MJ, Woo RS. Multiple low-dose radiation-induced neuronal cysteine transporter expression and oxidative stress are rescued by N-acetylcysteine in neuronal SH-SY5Y cells. Neurotoxicology 2023; 95:205-217. [PMID: 36796651 DOI: 10.1016/j.neuro.2023.02.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2022] [Revised: 01/13/2023] [Accepted: 02/13/2023] [Indexed: 02/16/2023]
Abstract
Recently, several studies have demonstrated that low-dose radiation (LDR) therapy has positively impacts on the treatment of Alzheimer's disease (AD). LDR suppresses the production of pro-neuroinflammation molecules and improves cognitive function in AD. However, it is unclear whether direct exposure to LDR causes beneficial effects and what mechanism is involved in neuronal cells. In this study, we first determined the effect of high-dose radiation (HDR) alone on C6 cells and SH-SY5Y cells. We found that SH-SY5Y cells were more vulnerable than C6 cells to HDR. Moreover, in neuronal SH-SY5Y cells exposed to single or multiple LDR, N-type cells showed decreased cell viability with increasing radiation exposure time and frequency, but S-type cells were unaffected. Multiple LDR increased proapoptotic molecules such as p53, Bax and cleaved caspase-3, and decreased anti-apoptotic molecule (Bcl2). Multiple LDR also generated free radicals in neuronal SH-SY5Y cells. We detected a change in the expression of the neuronal cysteine transporter EAAC1. Pretreatment with N-acetylcysteine (NAC) rescued the increased in EAAC1 expression and the generation of ROS in neuronal SH-SY5Y cells after multiple LDR. Furthermore, we verified whether the increased in EAAC1 expression induces cell defense or cell death promotion signaling. We showed that transient overexpression of EAAC1 reduced the multiple LDR-induced p53 overexpression in neuronal SH-SY5Y cells. Our results indicate that neuronal cells can be injured by increased production of ROS not only by HDR but also by multiple LDR, which suggests that combination treatment with anti-free radical agents such as NAC may be useful in multiple LDR therapy.
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Affiliation(s)
- Ji-Young Yoo
- Department of Anatomy and Neuroscience, College of Medicine, Eulji University, Daejeon 301-746, Republic of Korea
| | - Ye-Ji Lee
- Department of Anatomy and Neuroscience, College of Medicine, Eulji University, Daejeon 301-746, Republic of Korea
| | - Yu-Jin Kim
- Department of Anatomy and Neuroscience, College of Medicine, Eulji University, Daejeon 301-746, Republic of Korea
| | - Tai-Kyoung Baik
- Department of Anatomy and Neuroscience, College of Medicine, Eulji University, Daejeon 301-746, Republic of Korea
| | - Jun-Ho Lee
- Department of Emergency Medical Technology, Daejeon University, Daejeon 34520, Republic of Korea
| | - Mi-Jo Lee
- Department of Radiation Oncology, Eulji University Hospital, Daejeon 35233, Republic of Korea.
| | - Ran-Sook Woo
- Department of Anatomy and Neuroscience, College of Medicine, Eulji University, Daejeon 301-746, Republic of Korea.
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Xu P, Liu Q, Xie Y, Shi X, Li Y, Peng M, Guo H, Sun R, Li J, Hong Y, Liu X, Xu G. Breast cancer susceptibility protein 1 (BRCA1) rescues neurons from cerebral ischemia/reperfusion injury through NRF2-mediated antioxidant pathway. Redox Biol 2018; 18:158-172. [PMID: 30014904 PMCID: PMC6068089 DOI: 10.1016/j.redox.2018.06.012] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2018] [Revised: 06/27/2018] [Accepted: 06/30/2018] [Indexed: 11/30/2022] Open
Abstract
Cellular oxidative stress plays a vital role in the pathological process of neural damage in cerebral ischemia/reperfusion (I/R). The breast cancer susceptibility protein 1 (BRCA1), a tumor suppressor, can modulate cellular antioxidant response and DNA repair. Yet the role of BRCA1 in cerebral I/R injury has not been explored. In this study, we observed that BRCA1 was mainly expressed in neurons and was up-regulated in response to I/R insult. Overexpression of BRCA1 attenuated reactive oxygen species production and lipid peroxidation. Enhanced BRCA1 expression promoted DNA double strand break repair through non-homologous end joining pathway. These effects consequently led to neuronal cell survival and neurological recovery. Mechanically, BRCA1 can interact with the nuclear factor (erythroid-derived 2)-like 2 (NRF2) through BRCA1 C-terminal (BRCT) domain. The cross-talk between BRCT and NRF2 activated the NRF2/Antioxidant Response Element signaling pathway and thus protected injured neurons during cerebral I/R. In conclusion, enhanced BRCA1 after cerebral I/R injury may attenuate or prevent neural damage from I/R via NRF2-mediated antioxidant pathway. The finding may provide a potential therapeutic target against ischemic stroke. BRCA1 was up-regulated after cerebral ischemia/reperfusion injury. Up-regulated BRCA1 attenuated cerebral ischemia/reperfusion injury and cognitive impairment. BRCA1 binding to NRF2 via BRCT domain triggered NRF2-mediated antioxidant response. BRCA1 promoted DSBs repair via non-homologous end joining-pathway.
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Affiliation(s)
- Pengfei Xu
- Department of Neurology, Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu 210002, China
| | - Qian Liu
- Department of Neurology, Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu 210002, China
| | - Yi Xie
- Department of Neurology, Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu 210002, China
| | - Xiaolei Shi
- Kinsmen Laboratory of Neurological Research, University of British Columbia, Vancouver, British Columbia, Canada; Department of Neurology, The First Affiliated Hospital, Yijishan Hospital of Wannan Medical College, Wuhu, Anhui 241001, China
| | - Yunzi Li
- Department of Neurology, Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu 210002, China
| | - Mengna Peng
- Department of Neurology, Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu 210002, China
| | - Hongquan Guo
- Department of Neurology, Jinling Hospital, Southern Medical University, Nanjing, Jiangsu 210002, China
| | - Rui Sun
- Department of Neurology, Jinling Clinical College of Nanjing Medical University, Nanjing, Jiangsu 210002, China
| | - Juanji Li
- Department of Neurology, Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu 210002, China
| | - Ye Hong
- Department of Neurology, Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu 210002, China
| | - Xinfeng Liu
- Department of Neurology, Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu 210002, China.
| | - Gelin Xu
- Department of Neurology, Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu 210002, China.
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Yang B, Ren BX, Tang FR. Prenatal irradiation-induced brain neuropathology and cognitive impairment. Brain Dev 2017; 39:10-22. [PMID: 27527732 DOI: 10.1016/j.braindev.2016.07.008] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/29/2016] [Revised: 07/26/2016] [Accepted: 07/28/2016] [Indexed: 02/06/2023]
Abstract
Embryo/fetus is much more radiosensitive than neonatal and adult human being. The main potential effects of pre-natal radiation exposure on the human brain include growth retardation, small head/brain size, mental retardation, neocortical ectopias, callosal agenesis and brain tumor which may result in a lifetime poor quality of life. The patterns of prenatal radiation-induced effects are dependent not only on the stages of fetal development, the sensitivity of tissues and organs, but also on radiation sources, doses, dose rates. With the increased use of low dose radiation for diagnostic or radiotherapeutic purposes in recent years, combined with postnatal negative health effect after prenatal radiation exposure to fallout of Chernobyl nuclear power plant accident, the great anxiety and unnecessary termination of pregnancies after the nuclear disaster, there is a growing concern about the health effect of radiological examinations or therapies in pregnant women. In this paper, we reviewed current research progresses on pre-natal ionizing irradiation-induced abnormal brain structure changes. Subsequent postnatal neuropsychological and neurological diseases were provided. Relationship between irradiation and brain aging was briefly mentioned. The relevant molecular mechanisms were also discussed. Future research directions were proposed at the end of this paper. With limited human data available, we hoped that systematical review of animal data could relight research interests on prenatal low dose/dose rate irradiation-induced brain microanatomical changes and subsequent neurological and neuropsychological disorders.
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Affiliation(s)
- Bo Yang
- Medical School of Yangtze University, People's Republic of China
| | - Bo Xu Ren
- Medical School of Yangtze University, People's Republic of China.
| | - Feng Ru Tang
- Radiobiology Research Laboratory, Singapore Nuclear Research and Safety Initiative (SNRSI), National University of Singapore, Singapore.
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Shimada M, Matsuzaki F, Kato A, Kobayashi J, Matsumoto T, Komatsu K. Induction of Excess Centrosomes in Neural Progenitor Cells during the Development of Radiation-Induced Microcephaly. PLoS One 2016; 11:e0158236. [PMID: 27367050 PMCID: PMC4930206 DOI: 10.1371/journal.pone.0158236] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2016] [Accepted: 06/12/2016] [Indexed: 11/19/2022] Open
Abstract
The embryonic brain is one of the tissues most vulnerable to ionizing radiation. In this study, we showed that ionizing radiation induces apoptosis in the neural progenitors of the mouse cerebral cortex, and that the surviving progenitor cells subsequently develop a considerable amount of supernumerary centrosomes. When mouse embryos at Day 13.5 were exposed to γ-rays, brains sizes were reduced markedly in a dose-dependent manner, and these size reductions persisted until birth. Immunostaining with caspase-3 antibodies showed that apoptosis occurred in 35% and 40% of neural progenitor cells at 4 h after exposure to 1 and 2 Gy, respectively, and this was accompanied by a disruption of the apical layer in which mitotic spindles were positioned in unirradiated mice. At 24 h after 1 Gy irradiation, the apoptotic cells were completely eliminated and proliferation was restored to a level similar to that of unirradiated cells, but numerous spindles were localized outside the apical layer. Similarly, abnormal cytokinesis, which included multipolar division and centrosome clustering, was observed in 19% and 24% of the surviving neural progenitor cells at 48 h after irradiation with 1 and 2 Gy, respectively. Because these cytokinesis aberrations derived from excess centrosomes result in growth delay and mitotic catastrophe-mediated cell elimination, our findings suggest that, in addition to apoptosis at an early stage of radiation exposure, radiation-induced centrosome overduplication could contribute to the depletion of neural progenitors and thereby lead to microcephaly.
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Affiliation(s)
- Mikio Shimada
- Department of Genome Repair Dynamics, Radiation Biology Center, Kyoto University, Kyoto, Japan
| | - Fumio Matsuzaki
- Laboratory for Cell Asymmetry, Center for Developmental Biology, RIKEN, Kobe, Japan
| | - Akihiro Kato
- Department of Genome Repair Dynamics, Radiation Biology Center, Kyoto University, Kyoto, Japan
| | - Junya Kobayashi
- Department of Genome Repair Dynamics, Radiation Biology Center, Kyoto University, Kyoto, Japan
| | - Tomohiro Matsumoto
- Department of Radiation System Biology, Radiation Biology Center, Kyoto University, Kyoto, Japan
| | - Kenshi Komatsu
- Department of Genome Repair Dynamics, Radiation Biology Center, Kyoto University, Kyoto, Japan
- * E-mail:
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Leak RK, Li P, Zhang F, Sulaiman HH, Weng Z, Wang G, Stetler RA, Shi Y, Cao G, Gao Y, Chen J. Apurinic/apyrimidinic endonuclease 1 upregulation reduces oxidative DNA damage and protects hippocampal neurons from ischemic injury. Antioxid Redox Signal 2015; 22:135-48. [PMID: 24180454 PMCID: PMC4281843 DOI: 10.1089/ars.2013.5511] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
AIMS Apurinic/apyrimidinic endonuclease 1 (APE1) is a multifunctional enzyme that participates in base-excision repair of oxidative DNA damage and in the redox activation of transcription factors. We tested the hypothesis that APE1 upregulation protects neuronal structure and function against transient global cerebral ischemia (tGCI). RESULTS Upregulation of APE1 by low-dose proton irradiation (PI) or by transgene overexpression protected hippocampal CA1 neurons against tGCI-induced cell loss and reduced apurinic/apyrimidinic sites and DNA fragmentation. Conversely, APE1 knockdown attenuated the protection afforded by PI and ischemic preconditioning. APE1 overexpression inhibited the DNA damage response, as evidenced by lower phospho-histone H2A and p53-upregulated modulator of apoptosis levels. APE1 overexpression also partially rescued dendritic spines and attenuated the decrease in field excitatory postsynaptic potentials in hippocampal CA1. Presynaptic and postsynaptic markers were reduced after tGCI, and this effect was blunted in APE1 transgenics. The Morris water maze test revealed that APE1 protected against learning and memory deficits for at least 27 days post-injury. Animals expressing DNA repair-disabled mutant APE1 (D210A) exhibited more DNA damage than wild-type controls and were not protected against tGCI-induced cell loss. INNOVATION This is the first study that thoroughly characterizes structural and functional protection against ischemia after APE1 upregulation by measuring synaptic markers, electrophysiological function, and long-term neurological deficits in vivo. Furthermore, disabling the DNA repair activity of APE1 was found to abrogate its protective impact. CONCLUSION APE1 upregulation, either endogenously or through transgene overexpression, protects DNA, neuronal structures, synaptic function, and behavioral output from ischemic injury.
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Affiliation(s)
- Rehana K Leak
- 1 State Key Laboratory of Medical Neurobiology and Institute of Brain Sciences, Fudan University , Shanghai, China
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Liu WW, Chen SY, Cheng CH, Cheng HJ, Huang PH. Blm-s , a BH3-Only Protein Enriched in Postmitotic Immature Neurons, Is Transcriptionally Upregulated by p53 during DNA Damage. Cell Rep 2014; 9:166-179. [DOI: 10.1016/j.celrep.2014.08.050] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2013] [Revised: 07/05/2014] [Accepted: 08/20/2014] [Indexed: 12/25/2022] Open
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Kumar V, Alt FW, Oksenych V. Reprint of "Functional overlaps between XLF and the ATM-dependent DNA double strand break response". DNA Repair (Amst) 2014; 17:52-63. [PMID: 24767946 DOI: 10.1016/j.dnarep.2014.04.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2013] [Revised: 01/14/2014] [Accepted: 01/24/2014] [Indexed: 02/08/2023]
Abstract
Developing B and T lymphocytes generate programmed DNA double strand breaks (DSBs) during the V(D)J recombination process that assembles exons that encode the antigen-binding variable regions of antibodies. In addition, mature B lymphocytes generate programmed DSBs during the immunoglobulin heavy chain (IgH) class switch recombination (CSR) process that allows expression of different antibody heavy chain constant regions that provide different effector functions. During both V(D)J recombination and CSR, DSB intermediates are sensed by the ATM-dependent DSB response (DSBR) pathway, which also contributes to their joining via classical non-homologous end-joining (C-NHEJ). The precise nature of the interplay between the DSBR and C-NHEJ pathways in the context of DSB repair via C-NHEJ remains under investigation. Recent studies have shown that the XLF C-NHEJ factor has functional redundancy with several members of the ATM-dependent DSBR pathway in C-NHEJ, highlighting unappreciated major roles for both XLF as well as the DSBR in V(D)J recombination, CSR and C-NHEJ in general. In this review, we discuss current knowledge of the mechanisms that contribute to the repair of DSBs generated during B lymphocyte development and activation with a focus on potential functionally redundant roles of XLF and ATM-dependent DSBR factors.
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Affiliation(s)
- Vipul Kumar
- Howard Hughes Medical Institute, Program in Cellular and Molecular Medicine, Boston Children's Hospital, Department of Genetics, Harvard Medical School, Boston, MA 02115, United States
| | - Frederick W Alt
- Howard Hughes Medical Institute, Program in Cellular and Molecular Medicine, Boston Children's Hospital, Department of Genetics, Harvard Medical School, Boston, MA 02115, United States.
| | - Valentyn Oksenych
- Howard Hughes Medical Institute, Program in Cellular and Molecular Medicine, Boston Children's Hospital, Department of Genetics, Harvard Medical School, Boston, MA 02115, United States.
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Pao GM, Zhu Q, Perez-Garcia CG, Chou SJ, Suh H, Gage FH, O’Leary DDM, Verma IM. Role of BRCA1 in brain development. Proc Natl Acad Sci U S A 2014; 111:E1240-8. [PMID: 24639535 PMCID: PMC3977248 DOI: 10.1073/pnas.1400783111] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Breast cancer susceptibility gene 1 (BRCA1) is a breast and ovarian cancer tumor suppressor whose loss leads to DNA damage and defective centrosome functions. Despite its tumor suppression functions, BRCA1 is most highly expressed in the embryonic neuroepithelium when the neural progenitors are highly proliferative. To determine its functional significance, we deleted BRCA1 in the developing brain using a neural progenitor-specific driver. The phenotype is characterized by severe agenesis of multiple laminated cerebral structures affecting most notably the neocortex, hippocampus, cerebellum, and olfactory bulbs. Major phenotypes are caused by excess apoptosis, as these could be significantly suppressed by the concomitant deletion of p53. Certain phenotypes attributable to centrosomal and cell polarity functions could not be rescued by p53 deletion. A double KO with the DNA damage sensor kinase ATM was able to rescue BRCA1 loss to a greater extent than p53. Our results suggest distinct apoptotic and centrosomal functions of BRCA1 in neural progenitors, with important implications to understand the sensitivity of the embryonic brain to DNA damage, as well as the developmental regulation of brain size.
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Affiliation(s)
| | | | - Carlos G. Perez-Garcia
- Molecular Neurobiology Laboratory, The Salk Institute for Biological Studies, La Jolla, CA 92037
| | - Shen-Ju Chou
- Molecular Neurobiology Laboratory, The Salk Institute for Biological Studies, La Jolla, CA 92037
| | | | | | - Dennis D. M. O’Leary
- Molecular Neurobiology Laboratory, The Salk Institute for Biological Studies, La Jolla, CA 92037
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Kumar V, Alt FW, Oksenych V. Functional overlaps between XLF and the ATM-dependent DNA double strand break response. DNA Repair (Amst) 2014; 16:11-22. [PMID: 24674624 DOI: 10.1016/j.dnarep.2014.01.010] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2013] [Revised: 01/14/2014] [Accepted: 01/24/2014] [Indexed: 11/27/2022]
Abstract
Developing B and T lymphocytes generate programmed DNA double strand breaks (DSBs) during the V(D)J recombination process that assembles exons that encode the antigen-binding variable regions of antibodies. In addition, mature B lymphocytes generate programmed DSBs during the immunoglobulin heavy chain (IgH) class switch recombination (CSR) process that allows expression of different antibody heavy chain constant regions that provide different effector functions. During both V(D)J recombination and CSR, DSB intermediates are sensed by the ATM-dependent DSB response (DSBR) pathway, which also contributes to their joining via classical non-homologous end-joining (C-NHEJ). The precise nature of the interplay between the DSBR and C-NHEJ pathways in the context of DSB repair via C-NHEJ remains under investigation. Recent studies have shown that the XLF C-NHEJ factor has functional redundancy with several members of the ATM-dependent DSBR pathway in C-NHEJ, highlighting unappreciated major roles for both XLF as well as the DSBR in V(D)J recombination, CSR and C-NHEJ in general. In this review, we discuss current knowledge of the mechanisms that contribute to the repair of DSBs generated during B lymphocyte development and activation with a focus on potential functionally redundant roles of XLF and ATM-dependent DSBR factors.
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Affiliation(s)
- Vipul Kumar
- Howard Hughes Medical Institute, Program in Cellular and Molecular Medicine, Boston Children's Hospital, Department of Genetics, Harvard Medical School, Boston, MA 02115, United States
| | - Frederick W Alt
- Howard Hughes Medical Institute, Program in Cellular and Molecular Medicine, Boston Children's Hospital, Department of Genetics, Harvard Medical School, Boston, MA 02115, United States.
| | - Valentyn Oksenych
- Howard Hughes Medical Institute, Program in Cellular and Molecular Medicine, Boston Children's Hospital, Department of Genetics, Harvard Medical School, Boston, MA 02115, United States.
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Li P, Hu X, Gan Y, Gao Y, Liang W, Chen J. Mechanistic insight into DNA damage and repair in ischemic stroke: exploiting the base excision repair pathway as a model of neuroprotection. Antioxid Redox Signal 2011; 14:1905-18. [PMID: 20677909 PMCID: PMC3078503 DOI: 10.1089/ars.2010.3451] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Stroke is a common cause of death and serious long-term adult disability. Oxidative DNA damage is a severe consequence of oxidative stress associated with ischemic stroke. The accumulation of DNA lesions, including oxidative base modifications and strand breaks, triggers cell death in neurons and other vulnerable cell populations in the ischemic brain. DNA repair systems, particularly base excision repair, are endogenous defense mechanisms that combat oxidative DNA damage. The capacity for DNA repair may affect the susceptibility of neurons to ischemic stress and influence the pathological outcome of stroke. This article reviews the accumulated understanding of molecular pathways by which oxidative DNA damage is triggered and repaired in ischemic cells, and the potential impact of these pathways on ischemic neuronal cell death/survival. Genetic or pharmacological strategies that target the signaling molecules in DNA repair responses are promising for potential clinically effective treatment. Further understanding of mechanisms for oxidative DNA damage and its repair processes may lead to new avenues for stroke management.
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Affiliation(s)
- Peiying Li
- Anesthesiology Department of Huashan Hospital, State Key Laboratory of Medical Neurobiology, Fudan University, Shanghai, China
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