1
|
Kitaoka M, Yamashita YM. Running the gauntlet: challenges to genome integrity in spermiogenesis. Nucleus 2024; 15:2339220. [PMID: 38594652 PMCID: PMC11005813 DOI: 10.1080/19491034.2024.2339220] [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: 02/23/2024] [Accepted: 04/02/2024] [Indexed: 04/11/2024] Open
Abstract
Species' continuity depends on gametogenesis to produce the only cell types that can transmit genetic information across generations. Spermiogenesis, which encompasses post-meiotic, haploid stages of male gametogenesis, is a process that leads to the formation of sperm cells well-known for their motility. Spermiogenesis faces three major challenges. First, after two rounds of meiotic divisions, the genome lacks repair templates (no sister chromatids, no homologous chromosomes), making it incredibly vulnerable to any genomic insults over an extended time (typically days-weeks). Second, the sperm genome becomes transcriptionally silent, making it difficult to respond to new perturbations as spermiogenesis progresses. Third, the histone-to-protamine transition, which is essential to package the sperm genome, counterintuitively involves DNA break formation. How spermiogenesis handles these challenges remains poorly understood. In this review, we discuss each challenge and their intersection with the biology of protamines. Finally, we discuss the implication of protamines in the process of evolution.
Collapse
Affiliation(s)
- Maiko Kitaoka
- Whitehead Institute for Biomedical Research and Howard Hughes Medical Institute, Cambridge, MA, USA
| | - Yukiko M. Yamashita
- Whitehead Institute for Biomedical Research and Howard Hughes Medical Institute, Cambridge, MA, USA
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA, USA
| |
Collapse
|
2
|
Guo C, Wang Q, Shuai P, Wang T, Wu W, Li Y, Huang S, Yu J, Yi L. Radiation and male reproductive system: Damage and protection. CHEMOSPHERE 2024; 357:142030. [PMID: 38626814 DOI: 10.1016/j.chemosphere.2024.142030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2023] [Revised: 03/10/2024] [Accepted: 04/10/2024] [Indexed: 04/26/2024]
Abstract
Male fertility has been declining in recent decades, and a growing body of research points to environmental and lifestyle factors as the cause. The widespread use of radiation technology may result in more people affected by male infertility, as it is well established that radiation can cause reproductive impairment in men. This article provides a review of radiation-induced damage to male reproduction, and the effects of damage mechanisms and pharmacotherapy. It is hoped that this review will contribute to the understanding of the effects of radiation on male reproduction, and provide information for research into drugs that can protect the reproductive health of males.
Collapse
Affiliation(s)
- Caimao Guo
- Institute of Pharmacy and Pharmacology, Institute of Cytology and Genetics, The Hengyang Key Laboratory of Cellular Stress Biology, Hunan Province Cooperative Innovation Center for Molecular Target New Drug Study, Hengyang Medical School, University of South China, Hengyang, Hunan, 421001, China
| | - Qingyu Wang
- Institute of Pharmacy and Pharmacology, Institute of Cytology and Genetics, The Hengyang Key Laboratory of Cellular Stress Biology, Hunan Province Cooperative Innovation Center for Molecular Target New Drug Study, Hengyang Medical School, University of South China, Hengyang, Hunan, 421001, China
| | - Peimeng Shuai
- Institute of Pharmacy and Pharmacology, Institute of Cytology and Genetics, The Hengyang Key Laboratory of Cellular Stress Biology, Hunan Province Cooperative Innovation Center for Molecular Target New Drug Study, Hengyang Medical School, University of South China, Hengyang, Hunan, 421001, China
| | - Tiantian Wang
- Institute of Pharmacy and Pharmacology, Institute of Cytology and Genetics, The Hengyang Key Laboratory of Cellular Stress Biology, Hunan Province Cooperative Innovation Center for Molecular Target New Drug Study, Hengyang Medical School, University of South China, Hengyang, Hunan, 421001, China
| | - Wenyu Wu
- Institute of Pharmacy and Pharmacology, Institute of Cytology and Genetics, The Hengyang Key Laboratory of Cellular Stress Biology, Hunan Province Cooperative Innovation Center for Molecular Target New Drug Study, Hengyang Medical School, University of South China, Hengyang, Hunan, 421001, China
| | - Yuanyuan Li
- Institute of Pharmacy and Pharmacology, Institute of Cytology and Genetics, The Hengyang Key Laboratory of Cellular Stress Biology, Hunan Province Cooperative Innovation Center for Molecular Target New Drug Study, Hengyang Medical School, University of South China, Hengyang, Hunan, 421001, China
| | - Shuqi Huang
- Institute of Pharmacy and Pharmacology, Institute of Cytology and Genetics, The Hengyang Key Laboratory of Cellular Stress Biology, Hunan Province Cooperative Innovation Center for Molecular Target New Drug Study, Hengyang Medical School, University of South China, Hengyang, Hunan, 421001, China
| | - Jia Yu
- Institute of Pharmacy and Pharmacology, Institute of Cytology and Genetics, The Hengyang Key Laboratory of Cellular Stress Biology, Hunan Province Cooperative Innovation Center for Molecular Target New Drug Study, Hengyang Medical School, University of South China, Hengyang, Hunan, 421001, China.
| | - Lan Yi
- Institute of Pharmacy and Pharmacology, Institute of Cytology and Genetics, The Hengyang Key Laboratory of Cellular Stress Biology, Hunan Province Cooperative Innovation Center for Molecular Target New Drug Study, Hengyang Medical School, University of South China, Hengyang, Hunan, 421001, China.
| |
Collapse
|
3
|
Giulioni C, Maurizi V, Galosi AB. The role of physical agents' exposure in male infertility: A critical review. Arch Ital Urol Androl 2023; 95:10890. [PMID: 36924383 DOI: 10.4081/aiua.2023.10890] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2022] [Accepted: 10/24/2022] [Indexed: 02/24/2023] Open
Abstract
BACKGROUND A decrease in semen quality is an increasingly widespread pathological condition worldwide. Jobs and lifestyles have changed a lot with the advancement of technology in the last few decades, and a new series of risk factors for male infertility have spread. OBJECTIVE This review aims to summarize the current literature on this relationship, evaluating alterations in semen parameters and hormonal profile. METHODS A deep research was performed through MEDLINE via PubMed, Scopus, and Web of Science on articles regarding the relationship between physical agents and male fertility over the last twenty years. Some physical agents already associated with male infertility, such as heat and radiation, while emerging ones, such as physical exertion, psychological stress and sedentary activities, were newly considered. RESULTS Most studies described sperm quality after exposure. Overall sperm impairment was shown after radiation and alteration of specific parameters, such as sperm concentration, were observed after psychological stress and sedentary work. In addition, an association was also reported between physical exertion and hormonal profile, especially pituitary hormones and testosterone. CONCLUSIONS Although the associations between physical agents and male infertility are suggestive, the level of evidence of the studies is not adequate to define their influence, except for physical exertion. Therefore, new prospective studies are necessary for the validation of the correlation and the possible safeguarding of the exposed working classes.
Collapse
Affiliation(s)
- Carlo Giulioni
- Department of Urology, Polytechnic University of Marche Region, Umberto I Hospital "Ospedali Riuniti", Ancona.
| | - Valentina Maurizi
- Department of Clinical and Molecular Sciences, Polytechnic University of Marche Region, "Ospedali Riuniti" University Hospital, Ancona.
| | - Andrea Benedetto Galosi
- Department of Urology, Polytechnic University of Marche Region, Umberto I Hospital "Ospedali Riuniti", Ancona.
| |
Collapse
|
4
|
Le W, Zhou F, Xiang J, Weng Y, Wu D, Xu J, Zhang J. Preliminary Study on 53BP1-Mediated DNA Double-Strand Break Response in Spermatogonial Stem Cells. Reprod Sci 2022; 30:1572-1584. [PMID: 36446980 DOI: 10.1007/s43032-022-01122-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2022] [Accepted: 10/30/2022] [Indexed: 11/30/2022]
Abstract
53BP1 mediates DNA repair process in somatic cells; however, the function of 53BP1 in germline stem cells still remains unclear. In the present study, animals and cells DNA damage repair (DDR) model was established by irradiation and HU treatment; immunofluorescence staining and laser confocal microscopy were used to detect the expression of 53BP1, p-CHK2, and p-P53 in the DDR process of mSSCs. 53BP1 knockdown expression mSSCs cell line conducted by Trp53bp1-shRNA was established and EdU staining was adopted to analyze cell cycle and cell proliferation. Moreover, NHEJ reporter vector was applied to detect the repair efficacy after Trp53bp1 knocked-down (KD) expression. Results showed that 53BP1 could form foci signals in mSSCs during DDR process both in vivo and in vitro, which was independent of γH2AX. 53BP1 downstream protein, p-P53, and p-CHK2 were involved and dynamically expressed in DDR response. Knocking down of Trp53bp1 expression in mSSCs could not dramatically inhibit cell proliferation, but may increase cell sensitivity to HU. The NHEJ repair efficacy was sharply decreased in Trp53bp-KD SSCs via flow cytometry analysis. We revealed the specific mechanism of 53BP1 in SSCs DDR process, which is expected to provide a new theoretical basis and insights for the diagnosis and treatment of male infertility.
Collapse
Affiliation(s)
- Wei Le
- Department of Urology, Tongji Hospital, Tongji University School of Medicine, 389 Xincun Road, Shanghai, 200065, China
| | - Fang Zhou
- Department of Surgery, Tongren Hospital, Shanghai Jiaotong University School of Medicine, 1111 Xianxia Road, Shanghai, 200050, China
| | - Jun Xiang
- Department of Urology, Tongji Hospital, Tongji University School of Medicine, 389 Xincun Road, Shanghai, 200065, China
| | - Yiming Weng
- Department of Reproductive Medicine, Tongji Hospital, Tongji University School of Medicine, 389 Xincun Road, Shanghai, 200065, China
| | - Denglong Wu
- Department of Urology, Tongji Hospital, Tongji University School of Medicine, 389 Xincun Road, Shanghai, 200065, China
| | - Jun Xu
- Department of Regenerative Medicine, East Hospital, Tongji University School of Medicine, 1239 Siping Road, Shanghai, 200120, China
| | - Jinfu Zhang
- Department of Reproductive Medicine, Guanghua Hospital Affiliated to Shanghai University of Traditional Chinese Medicine, 540 Xinhua Road, Shanghai, 200052, China.
| |
Collapse
|
5
|
Talibova G, Bilmez Y, Ozturk S. DNA double-strand break repair in male germ cells during spermatogenesis and its association with male infertility development. DNA Repair (Amst) 2022; 118:103386. [DOI: 10.1016/j.dnarep.2022.103386] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2022] [Revised: 08/01/2022] [Accepted: 08/03/2022] [Indexed: 11/16/2022]
|
6
|
Fukunaga H, Yokoya A, Prise KM. A Brief Overview of Radiation-Induced Effects on Spermatogenesis and Oncofertility. Cancers (Basel) 2022; 14:cancers14030805. [PMID: 35159072 PMCID: PMC8834293 DOI: 10.3390/cancers14030805] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2021] [Revised: 02/03/2022] [Accepted: 02/03/2022] [Indexed: 02/06/2023] Open
Abstract
Simple Summary Spermatogenesis is one of the most important processes for the propagation of life; however, the testes’ ability to form sperm via this differentiation process is highly radiosensitive and easily impacted by exposure to environmental, occupational, or therapeutic radiation. Furthermore, the possibility that radiation effects on the gonads can be passed on from generation to generation should not be overlooked. This review focuses on the radiation-induced effects on spermatogenesis and the transgenerational effects. We also explore the potential of novel radiobiological approaches to improve male fertility preservation during radiotherapy. Abstract The genotoxicity of radiation on germ cells may be passed on to the next generation, thus its elucidation is not only a scientific issue but also an ethical, legal, and social issue in modern society. In this article, we briefly overview the effects of radiation on spermatogenesis and its associated genotoxicity, including the latest findings in the field of radiobiology. The potential role of transgenerational effects is still poorly understood, and further research in this area is desirable. Furthermore, from the perspective of oncofertility, we discuss the historical background and clinical importance of preserving male fertility during radiation treatment and the potential of microbeam radiotherapy. We hope that this review will contribute to stimulating further discussions and investigations for therapies for pediatric and adolescent/young adult patients.
Collapse
Affiliation(s)
- Hisanori Fukunaga
- Center for Environmental and Health Sciences, Hokkaido University, Sapporo 060-0812, Japan
- Correspondence:
| | - Akinari Yokoya
- Institute for Quantum Life Science, National Institutes for Quantum Science and Technology, Ibaraki 319-1106, Japan;
- Graduate School of Science and Engineering, Ibaraki University, Ibaraki 310-8512, Japan
| | - Kevin M. Prise
- Patrick G Johnstone Centre for Cancer Research, Queen’s University Belfast, Belfast BT9 7AE, UK;
| |
Collapse
|
7
|
Pini T, Haywood M, McCallie B, Lane SL, Schoolcraft WB, Katz-Jaffe M. Liquid chromatography-tandem mass spectrometry reveals an active response to DNA damage in human spermatozoa. F&S SCIENCE 2021; 2:153-163. [PMID: 35559750 DOI: 10.1016/j.xfss.2021.03.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/14/2021] [Revised: 02/23/2021] [Accepted: 03/13/2021] [Indexed: 01/07/2023]
Abstract
OBJECTIVE To investigate how endogenously elevated DNA fragmentation alters the human sperm proteome, and whether this fragmentation contributes to genomic deletions. DESIGN Research study. SETTING Commercial fertility clinic. PATIENT(S) Men with low (0%-4%, n = 7) or high (≥16%, n = 6) sperm DNA fragmentation, as assessed by terminal deoxynucleotidyl transferase dUTP nick end labeling assay. INTERVENTION(S) None. MAIN OUTCOME MEASURE(S) Global sperm proteome, single-nucleotide polymorphism genotyping array. RESULT(S) A total of 78 significantly differentially abundant proteins (30 decreased, 48 increased) were observed in control vs. high DNA damage samples. DNA damage resulted in robust proteomic responses, including markers of oxidative stress and apoptosis, DNA damage repair proteins, and transcription/translation and protein turnover machinery. Several key sperm functional proteins were significantly decreased in ejaculates with high DNA damage. We were unable to substantiate a link between increased DNA fragmentation and genomic deletions in human spermatozoa. CONCLUSION(S) Developing human spermatozoa initiate an active transcriptional response to endogenous DNA damage, which manifests as alterations in the sperm proteome.
Collapse
Affiliation(s)
- Taylor Pini
- Colorado Center for Reproductive Medicine, Lone Tree, Colorado.
| | - Mary Haywood
- Colorado Center for Reproductive Medicine, Lone Tree, Colorado
| | - Blair McCallie
- Colorado Center for Reproductive Medicine, Lone Tree, Colorado
| | - Sydney L Lane
- Colorado Center for Reproductive Medicine, Lone Tree, Colorado
| | | | | |
Collapse
|
8
|
Mori Y, Ogonuki N, Hasegawa A, Kanatsu-Shinohara M, Ogura A, Wang Y, McCarrey JR, Shinohara T. OGG1 protects mouse spermatogonial stem cells from reactive oxygen species in culture†. Biol Reprod 2020; 104:706-716. [PMID: 33252132 DOI: 10.1093/biolre/ioaa216] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Revised: 10/23/2020] [Accepted: 11/23/2020] [Indexed: 01/10/2023] Open
Abstract
Although reactive oxygen species (ROS) are required for spermatogonial stem cell (SSC) self-renewal, they induce DNA damage and are harmful to SSCs. However, little is known about how SSCs protect their genome during self-renewal. Here, we report that Ogg1 is essential for SSC protection against ROS. While cultured SSCs exhibited homologous recombination-based DNA double-strand break repair at levels comparable with those in pluripotent stem cells, they were significantly more resistant to hydrogen peroxide than pluripotent stem cells or mouse embryonic fibroblasts, suggesting that they exhibit high levels of base excision repair (BER) activity. Consistent with this observation, cultured SSCs showed significantly lower levels of point mutations than somatic cells, and showed strong expression of BER-related genes. Functional screening revealed that Ogg1 depletion significantly impairs survival of cultured SSCs upon hydrogen peroxide exposure. Thus, our results suggest increased expression of BER-related genes, including Ogg1, protects SSCs from ROS-induced damage.
Collapse
Affiliation(s)
- Yoshifumi Mori
- Department of Molecular Genetics, Graduate School of Medicine, Kyoto University, Kyoto 606-8501, Japan
| | - Narumi Ogonuki
- RIKEN, BioResource Research Center, Tsukuba 305-0074, Japan
| | - Ayumi Hasegawa
- RIKEN, BioResource Research Center, Tsukuba 305-0074, Japan
| | - Mito Kanatsu-Shinohara
- Department of Molecular Genetics, Graduate School of Medicine, Kyoto University, Kyoto 606-8501, Japan
| | - Atsuo Ogura
- RIKEN, BioResource Research Center, Tsukuba 305-0074, Japan
| | - Yufeng Wang
- Department of Biology, University of Texas at San Antonio, San Antonio, TX 78249, USA
| | - John R McCarrey
- Department of Biology, University of Texas at San Antonio, San Antonio, TX 78249, USA
| | - Takashi Shinohara
- Department of Molecular Genetics, Graduate School of Medicine, Kyoto University, Kyoto 606-8501, Japan
| |
Collapse
|
9
|
Houston BJ, Nixon B, Martin JH, De Iuliis GN, Trigg NA, Bromfield EG, McEwan KE, Aitken RJ. Heat exposure induces oxidative stress and DNA damage in the male germ line. Biol Reprod 2019; 98:593-606. [PMID: 29351587 DOI: 10.1093/biolre/ioy009] [Citation(s) in RCA: 76] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2017] [Accepted: 01/15/2018] [Indexed: 12/13/2022] Open
Abstract
The reproductive consequences of global warming are not currently understood. In order to address this issue, we have examined the reproductive consequences of exposing male mice to a mild heat stress. For this purpose, adult male mice were exposed to an elevated ambient temperature of 35°C under two exposure models. The first involved acute exposure for 24 h, followed by recovery periods between 1 day and 6 weeks. The alternative heating regimen involved a daily exposure of 8 h for periods of 1 or 2 weeks. In our acute model, we identified elevated sperm mitochondrial ROS generation (P < 0.05), increased sperm membrane fluidity (P < 0.05), DNA damage in the form of single-strand breaks (P < 0.001), and oxidative DNA damage (P < 0.05), characteristic of an oxidative stress cascade. This DNA damage was detected in pachytene spermatocytes (P < 0.001) and round spermatids (P < 0.001) isolated from testes after 1 day heat recovery. Despite these lesions, the spermatozoa of heat-treated mice exhibited no differences in their ability to achieve hallmarks of capacitation or to fertilize the oocyte and support development of embryos to the blastocyst stage (all P > 0.05). Collectively, our acute heat stress model supports the existence of heat susceptible stages of germ cell development, with the round spermatids being most perturbed and spermatogonial stem cells exhibiting resistance to this insult. Such findings were complemented by our chronic heat stress model, which further supported the vulnerability of the round spermatid population.
Collapse
Affiliation(s)
- Brendan J Houston
- Priority Research Centre for Reproductive Science, School of Environmental and Life Sciences, Discipline of Biological Sciences, University of Newcastle, Callaghan, New South Wales, Australia
| | - Brett Nixon
- Priority Research Centre for Reproductive Science, School of Environmental and Life Sciences, Discipline of Biological Sciences, University of Newcastle, Callaghan, New South Wales, Australia
| | - Jacinta H Martin
- Priority Research Centre for Reproductive Science, School of Environmental and Life Sciences, Discipline of Biological Sciences, University of Newcastle, Callaghan, New South Wales, Australia
| | - Geoffry N De Iuliis
- Priority Research Centre for Reproductive Science, School of Environmental and Life Sciences, Discipline of Biological Sciences, University of Newcastle, Callaghan, New South Wales, Australia
| | - Natalie A Trigg
- Priority Research Centre for Reproductive Science, School of Environmental and Life Sciences, Discipline of Biological Sciences, University of Newcastle, Callaghan, New South Wales, Australia
| | - Elizabeth G Bromfield
- Priority Research Centre for Reproductive Science, School of Environmental and Life Sciences, Discipline of Biological Sciences, University of Newcastle, Callaghan, New South Wales, Australia
| | - Kristen E McEwan
- Priority Research Centre for Reproductive Science, School of Environmental and Life Sciences, Discipline of Biological Sciences, University of Newcastle, Callaghan, New South Wales, Australia
| | - R John Aitken
- Priority Research Centre for Reproductive Science, School of Environmental and Life Sciences, Discipline of Biological Sciences, University of Newcastle, Callaghan, New South Wales, Australia
| |
Collapse
|
10
|
DNA damage in aging, the stem cell perspective. Hum Genet 2019; 139:309-331. [PMID: 31324975 DOI: 10.1007/s00439-019-02047-z] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2019] [Accepted: 07/05/2019] [Indexed: 02/07/2023]
Abstract
DNA damage is one of the most consistent cellular process proposed to contribute to aging. The maintenance of genomic and epigenomic integrity is critical for proper function of cells and tissues throughout life, and this homeostasis is under constant strain from both extrinsic and intrinsic insults. Considering the relationship between lifespan and genotoxic burden, it is plausible that the longest-lived cellular populations would face an accumulation of DNA damage over time. Tissue-specific stem cells are multipotent populations residing in localized niches and are responsible for maintaining all lineages of their resident tissue/system throughout life. However, many of these stem cells are impacted by genotoxic stress. Several factors may dictate the specific stem cell population response to DNA damage, including the niche location, life history, and fate decisions after damage accrual. This leads to differential handling of DNA damage in different stem cell compartments. Given the importance of adult stem cells in preserving normal tissue function during an individual's lifetime, DNA damage sensitivity and accumulation in these compartments could have crucial implications for aging. Despite this, more support for direct functional effects driven by accumulated DNA damage in adult stem cell compartments is needed. This review will present current evidence for the accumulation and potential influence of DNA damage in adult tissue-specific stem cells and propose inquiry directions that could benefit individual healthspan.
Collapse
|
11
|
Beal MA, Meier MJ, Williams A, Rowan-Carroll A, Gagné R, Lindsay SJ, Fitzgerald T, Hurles ME, Marchetti F, Yauk CL. Paternal exposure to benzo(a)pyrene induces genome-wide mutations in mouse offspring. Commun Biol 2019; 2:228. [PMID: 31240266 PMCID: PMC6586636 DOI: 10.1038/s42003-019-0476-5] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2019] [Accepted: 05/23/2019] [Indexed: 01/14/2023] Open
Abstract
Understanding the effects of environmental exposures on germline mutation rates has been a decades-long pursuit in genetics. We used next-generation sequencing and comparative genomic hybridization arrays to investigate genome-wide mutations in the offspring of male mice exposed to benzo(a)pyrene (BaP), a common environmental pollutant. We demonstrate that offspring developing from sperm exposed during the mitotic or post-mitotic phases of spermatogenesis have significantly more de novo single nucleotide variants (1.8-fold; P < 0.01) than controls. Both phases of spermatogenesis are susceptible to the induction of heritable mutations, although mutations arising from post-fertilization events are more common after post-mitotic exposure. In addition, the mutation spectra in sperm and offspring of BaP-exposed males are consistent. Finally, we report a significant increase in transmitted copy number duplications (P = 0.001) in BaP-exposed sires. Our study demonstrates that germ cell mutagen exposures induce genome-wide mutations in the offspring that may be associated with adverse health outcomes.
Collapse
Affiliation(s)
- Marc A. Beal
- Carleton University, Ottawa, Ontario K1S 5B6 Canada
- Environmental Health Science and Research Bureau, Healthy Environments and Consumer Safety Branch, Health Canada, Ottawa, Ontario K1A 0K9 Canada
| | - Matthew J. Meier
- Environmental Health Science and Research Bureau, Healthy Environments and Consumer Safety Branch, Health Canada, Ottawa, Ontario K1A 0K9 Canada
| | - Andrew Williams
- Environmental Health Science and Research Bureau, Healthy Environments and Consumer Safety Branch, Health Canada, Ottawa, Ontario K1A 0K9 Canada
| | - Andrea Rowan-Carroll
- Environmental Health Science and Research Bureau, Healthy Environments and Consumer Safety Branch, Health Canada, Ottawa, Ontario K1A 0K9 Canada
| | - Rémi Gagné
- Environmental Health Science and Research Bureau, Healthy Environments and Consumer Safety Branch, Health Canada, Ottawa, Ontario K1A 0K9 Canada
| | - Sarah J. Lindsay
- Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge, CB10 1SA UK
| | - Tomas Fitzgerald
- Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge, CB10 1SA UK
| | - Matthew E. Hurles
- Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge, CB10 1SA UK
| | - Francesco Marchetti
- Environmental Health Science and Research Bureau, Healthy Environments and Consumer Safety Branch, Health Canada, Ottawa, Ontario K1A 0K9 Canada
| | - Carole L. Yauk
- Environmental Health Science and Research Bureau, Healthy Environments and Consumer Safety Branch, Health Canada, Ottawa, Ontario K1A 0K9 Canada
| |
Collapse
|
12
|
Bloom JC, Loehr AR, Schimenti JC, Weiss RS. Germline genome protection: implications for gamete quality and germ cell tumorigenesis. Andrology 2019; 7:516-526. [PMID: 31119900 DOI: 10.1111/andr.12651] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2019] [Revised: 04/25/2019] [Accepted: 04/26/2019] [Indexed: 12/19/2022]
Abstract
BACKGROUND Germ cells have a unique and critical role as the conduit for hereditary information and therefore employ multiple strategies to protect genomic integrity and avoid mutations. Unlike somatic cells, which often respond to DNA damage by arresting the cell cycle and conducting DNA repair, germ cells as well as long-lived pluripotent stem cells typically avoid the use of error-prone repair mechanisms and favor apoptosis, reducing the risk of genetic alterations. Testicular germ cell tumors, the most common cancers of young men, arise from pre-natal germ cells. OBJECTIVES To summarize the current understanding of DNA damage response mechanisms in pre-meiotic germ cells and to discuss how they impact both the origins of testicular germ cell tumors and their remarkable responsiveness to genotoxic chemotherapy. MATERIALS AND METHODS We conducted a review of literature gathered from PubMed regarding the DNA damage response properties of testicular germ cell tumors and the germ cells from which they arise, as well as the influence of these mechanisms on therapeutic responses by testicular germ cell tumors. RESULTS AND DISCUSSION This review provides a comprehensive evaluation of how the developmental origins of male germ cells and their inherent germ cell-like DNA damage response directly impact the development and therapeutic sensitivity of testicular germ cell tumors. CONCLUSIONS The DNA damage response of germ cells directly impacts the development and therapeutic sensitivity of testicular germ cell tumors. Recent advances in the study of primordial germ cells, post-natal mitotically dividing germ cells, and pluripotent stem cells will allow for new investigations into the initiation, progression, and treatment of testicular germ cell tumors.
Collapse
Affiliation(s)
- J C Bloom
- Department of Biomedical Sciences, Cornell University, Ithaca, NY, USA
| | - A R Loehr
- Department of Biomedical Sciences, Cornell University, Ithaca, NY, USA
| | - J C Schimenti
- Department of Biomedical Sciences, Cornell University, Ithaca, NY, USA
| | - R S Weiss
- Department of Biomedical Sciences, Cornell University, Ithaca, NY, USA
| |
Collapse
|
13
|
Pellestor F, Gatinois V. Chromoanasynthesis: another way for the formation of complex chromosomal abnormalities in human reproduction. Hum Reprod 2019; 33:1381-1387. [PMID: 30325427 DOI: 10.1093/humrep/dey231] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2018] [Indexed: 12/24/2022] Open
Abstract
Chromoanasynthesis has been described as a novel cause of massive constitutional chromosomal rearrangements. Based on DNA replication machinery defects, chromoanasynthesis is characterized by the presence of chromosomal duplications and triplications locally clustered on one single chromosome, or a few chromosomes, associated with various other types of structural rearrangements. Two distinct mechanisms have been described for the formation of these chaotic genomic disorders, i.e. the fork stalling and template switching and the microhomology-mediated break-induced replication. Micronucleus-based processes have been evidenced as a causative mechanism, thus, highlighting the close connection between segregation errors and structural rearrangements. Accumulating data indicate that chromoanasynthesis is operating in human germline cells and during early embryonic development. The development of new tools for quantifying chromoanasynthesis events should provide further insight into the impact of this catastrophic cellular phenomenon in human reproduction.
Collapse
Affiliation(s)
- Franck Pellestor
- Unit of Chromosomal Genetics, Department of Medical Genetics, Arnaud de Villeneuve Hospital, Montpellier CHU, Montpellier, France
| | - Vincent Gatinois
- Unit of Chromosomal Genetics, Department of Medical Genetics, Arnaud de Villeneuve Hospital, Montpellier CHU, Montpellier, France
| |
Collapse
|
14
|
Singh P, Aggarwal LM, Parry SA, Raman MJ. Radiation dosimetry and repair kinetics of DNA damage foci in mouse pachytene spermatocyte and round spermatid stages. Mutagenesis 2019; 33:231-239. [PMID: 30239864 DOI: 10.1093/mutage/gey007] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2017] [Accepted: 04/19/2018] [Indexed: 12/23/2022] Open
Abstract
Accurate quantification of DNA double strand breaks (DSB) in testicular germ cells is difficult because of cellular heterogeneity and the presence of endogenous γH2AX. Here, we used confocal microscopy to quantify DNA damage and repair kinetics following γ-irradiation (0.5-4 Gy) in three major mouse male germ cell stages, early and late pachytene spermatocytes and round spermatids (RSs), following a defined post irradiation time course. Dose-response curves showing linear best fit validated γH2AX focus as a rapid biodosimetric tool in these substages in response to whole body in vivo exposure. Stage specific foci yield/dose and repair kinetics demonstrated differential radiosensitivity and repair efficiency: early pachytenes (EP) repaired most rapidly and completely followed by late pachytene (LP) and RSs. Repair kinetics for all three stages followed 'exponential decay' in response to each radiation dose. In pachytenes immediate colocalisation of γH2AX and 53BP1, which participates in non-homologous end-joining repair pathway, was followed by dissociation from the major focal area of γH2AX by 4 h demonstrating ongoing DSB repair. These results confirm the differential radiosensitivity and repair kinetics of DSBs in male germ cells at different stages. Taken together, our results provide a simple and accurate method for assessing DNA damage and repair kinetics during spermatogenesis.
Collapse
Affiliation(s)
- Priti Singh
- Cytogenetics Laboratory, Department of Zoology, Centre of Advanced Study, India
| | - Lalit Mohan Aggarwal
- Department of Radiotherapy and Radiation Medicine, Institute of Medical Sciences, Banaras Hindu University, Varanasi, India
| | - Stephen A Parry
- Cornell Statistical Consulting Unit, Cornell University, Ithaca, NY, USA
| | - Mercy J Raman
- Cytogenetics Laboratory, Department of Zoology, Centre of Advanced Study, India
| |
Collapse
|
15
|
Zheng Y, Lei Q, Jongejan A, Mulder CL, van Daalen SKM, Mastenbroek S, Hwang G, Jordan PW, Repping S, Hamer G. The influence of retinoic acid-induced differentiation on the radiation response of male germline stem cells. DNA Repair (Amst) 2018; 70:55-66. [PMID: 30179733 PMCID: PMC6237089 DOI: 10.1016/j.dnarep.2018.08.027] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2018] [Revised: 08/23/2018] [Accepted: 08/27/2018] [Indexed: 12/19/2022]
Abstract
Lifelong mammalian male fertility is maintained through an intricate balance between spermatogonial proliferation and differentiation. DNA damage in spermatogonia, for instance caused by chemo- or radiotherapy, can induce cell cycle arrest or germ cell apoptosis, possibly resulting in male infertility. Spermatogonia are generally more radiosensitive and prone to undergo apoptosis than somatic cells. Among spermatogonial subtypes the response to DNA damage is differentially modulated; undifferentiated spermatogonia, including the spermatogonial stem cells (SSCs), are relatively radio-resistant, whereas differentiating spermatogonia are very radiosensitive. To investigate the molecular mechanisms underlying this difference, we used an in vitro system consisting of mouse male germline stem (GS) cells that can be induced to differentiate. Using RNA-sequencing analysis, we analyzed the response of undifferentiated and differentiating GS cells to ionizing radiation (IR). At the RNA expression level, both undifferentiated and differentiating GS cells showed a very similar response to IR. Protein localization of several genes found to be involved in either spermatogonial differentiation or radiation response was investigated using mouse testis sections. For instance, we found that the transcription factor PDX1 was specifically expressed in undifferentiated spermatogonia and thus may be a novel marker for these cells. Interestingly, also at the protein level, undifferentiated GS cells showed a more pronounced upregulation of p53 in response to IR than differentiating GS cells. The higher p53 protein level in undifferentiated spermatogonia may preferentially induce cell cycle arrest, thereby giving these cells more time to repair inflicted DNA damage and increase their radio-resistance.
Collapse
Affiliation(s)
- Yi Zheng
- College of Animal Science and Technology, Northwest A&F University, Shaanxi, China; Center for Reproductive Medicine, Amsterdam Research Institute Reproduction and Development, Academic Medical Center, University of Amsterdam, 1105 AZ, Amsterdam, The Netherlands
| | - Qijing Lei
- Center for Reproductive Medicine, Amsterdam Research Institute Reproduction and Development, Academic Medical Center, University of Amsterdam, 1105 AZ, Amsterdam, The Netherlands
| | - Aldo Jongejan
- Bioinformatics Laboratory, Department of Clinical Epidemiology, Biostatistics and Bioinformatics, Amsterdam Public Health Research Institute, Academic Medical Center Amsterdam, The Netherlands
| | - Callista L Mulder
- Center for Reproductive Medicine, Amsterdam Research Institute Reproduction and Development, Academic Medical Center, University of Amsterdam, 1105 AZ, Amsterdam, The Netherlands
| | - Saskia K M van Daalen
- Center for Reproductive Medicine, Amsterdam Research Institute Reproduction and Development, Academic Medical Center, University of Amsterdam, 1105 AZ, Amsterdam, The Netherlands
| | - Sebastiaan Mastenbroek
- Center for Reproductive Medicine, Amsterdam Research Institute Reproduction and Development, Academic Medical Center, University of Amsterdam, 1105 AZ, Amsterdam, The Netherlands
| | - Grace Hwang
- Department of Biochemistry and Molecular Biology, Johns Hopkins University Bloomberg School of Public Health, Baltimore, MD, USA
| | - Philip W Jordan
- Department of Biochemistry and Molecular Biology, Johns Hopkins University Bloomberg School of Public Health, Baltimore, MD, USA
| | - Sjoerd Repping
- Center for Reproductive Medicine, Amsterdam Research Institute Reproduction and Development, Academic Medical Center, University of Amsterdam, 1105 AZ, Amsterdam, The Netherlands
| | - Geert Hamer
- Center for Reproductive Medicine, Amsterdam Research Institute Reproduction and Development, Academic Medical Center, University of Amsterdam, 1105 AZ, Amsterdam, The Netherlands.
| |
Collapse
|
16
|
Le W, Qi L, Xu C, Xiang Z, Mao Z, Zhang J, Xu J, Wu D. Preliminary study of the homologous recombination repair pathway in mouse spermatogonial stem cells. Andrology 2018; 6:488-497. [PMID: 29577652 DOI: 10.1111/andr.12481] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2018] [Revised: 01/31/2018] [Accepted: 02/05/2018] [Indexed: 12/19/2022]
Abstract
The present study was designed to detect DNA repair response through the homologous recombination pathway in mouse spermatogonial stem cells. Mouse spermatogonial stem cells (mSSCs) were obtained from the adult DBA/2 mouse testes by MACS sorting. mSSCs and mice animals were divided into four groups (30 min, 2, 24 h, control) and treated with ionizing irradiation while the control group received pseudo-irradiation. Proteins involved in the homologous recombination pathway (γH2AX, ATM, RAD51, CtIP, and RPA2) were assessed in mSSCs both in vitro and in vivo. Moreover, the non-homologous end-joining or homologous recombination (NHEJ/HR) reporter plasmids were transfected into mSSCs to assess NHEJ/HR pathway activity after DNA double-strand break (DSB). γH2AX, a classical DNA DSB marker, was absent in mSSCs both in vivo and in vitro after DSB repair, but was highly expressed in other tissue stem cells. In addition, ATM and phosphorylated ATM (p-ATM) were involved in DNA damage response (DDR) in mSSCs. p-ATM foci were overexpressed immediately after irradiation (30 min and 2 h), but gradually decreased over the repair time. The HR pathway-related proteins, CtIP and RPA2 were negatively regulated after treatment in Western blot (WB). NHEJ/HR reporter plasmid transfection indicated that the HR pathway played a minor role in mSSCs during DDR, consistent with the WB findings. This study demonstrates that mSSCs may have a unique response to DNA damage since crucial proteins involved in HR pathway were negatively regulated after DSB. In addition, the expression level of p-ATM, but not γH2AX, was increased after DSB, suggesting that DNA damage repair in mSSCs might be a γH2AX-independent response. Furthermore, the HR pathway may play a minor role during DDR in mSSCs.
Collapse
Affiliation(s)
- W Le
- Department of Urology, Tongji Hospital, Tongji University School of Medicine, Shanghai, China
| | - L Qi
- Department of Urology, Tongji Hospital, Tongji University School of Medicine, Shanghai, China
| | - C Xu
- Department of Urology, Tongji Hospital, Tongji University School of Medicine, Shanghai, China
| | - Z Xiang
- Department of Urology, Tongji Hospital, Tongji University School of Medicine, Shanghai, China
| | - Z Mao
- Tongji University School of Life Sciences and Technology, Shanghai, China
| | - J Zhang
- Department of Reproductive Medicine and Andrology, Tongren Hospital Affiliated to Shanghai Jiao Tong University, Shanghai, China
| | - J Xu
- East Hospital, Tongji University School of Medicine, Shanghai, China
| | - D Wu
- Department of Urology, Tongji Hospital, Tongji University School of Medicine, Shanghai, China
| |
Collapse
|
17
|
Smart E, Lopes F, Rice S, Nagy B, Anderson RA, Mitchell RT, Spears N. Chemotherapy drugs cyclophosphamide, cisplatin and doxorubicin induce germ cell loss in an in vitro model of the prepubertal testis. Sci Rep 2018; 8:1773. [PMID: 29379115 PMCID: PMC5788858 DOI: 10.1038/s41598-018-19761-9] [Citation(s) in RCA: 50] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2017] [Accepted: 12/22/2017] [Indexed: 11/09/2022] Open
Abstract
Long term survival rates for childhood cancers is steadily increasing, however cancer survivors can experience fertility problems as a consequence of chemotherapy treatment. This is particularly problematic for young boys, for whom no fertility preservation treatment is yet established. Here, we have determined the effects on prepubertal mouse testis of three commonly used chemotherapy drugs; cyclophosphamide (using its active metabolite phosphoramide mustard), cisplatin and doxorubicin, exposing testicular fragments to a clinically relevant range of concentrations in vitro. All three drugs induced a specific and highly significant loss of germ cells, including spermatogonial stem cells. In contrast, there was no significant effect on somatic cells, for either Sertoli or interstitial cells. Time course analysis of cleaved Caspase-3 expression showed a significant increase in apoptosis eight hours prior to a detectable decrease in germ cell numbers following exposure to phosphoramide mustard or cisplatin, although this pattern was not seen following doxorubicin-exposure. Moreover, analysis of DNA damage at 16 h showed increased γH2AX expression in response to all three drugs. Overall, results show that cisplatin, doxorubicin and cyclophosphamide all specifically induce loss of germ cells, including of spermatogonial stem cells, in the prepubertal mouse testis at concentrations relevant to human therapeutic exposures.
Collapse
Affiliation(s)
- Ellie Smart
- Biomedical Sciences, University of Edinburgh, Edinburgh, EH8 9XD, United Kingdom.,Center for Dermatology Research, University of Manchester, Manchester, United Kingdom
| | - Federica Lopes
- Biomedical Sciences, University of Edinburgh, Edinburgh, EH8 9XD, United Kingdom
| | - Siobhan Rice
- Biomedical Sciences, University of Edinburgh, Edinburgh, EH8 9XD, United Kingdom.,Weatherall Institute of Molecular Medicine, MRC Molecular Haematology Unit, University of Oxford, Oxford, OX3 9DS,, United Kingdom
| | - Boglarka Nagy
- Biomedical Sciences, University of Edinburgh, Edinburgh, EH8 9XD, United Kingdom
| | - Richard A Anderson
- MRC Centre for Reproductive Health, University of Edinburgh, Edinburgh, EH16 4TJ, United Kingdom
| | - Rod T Mitchell
- MRC Centre for Reproductive Health, University of Edinburgh, Edinburgh, EH16 4TJ, United Kingdom
| | - Norah Spears
- Biomedical Sciences, University of Edinburgh, Edinburgh, EH8 9XD, United Kingdom.
| |
Collapse
|
18
|
Bose R, Sheng K, Moawad AR, Manku G, O'Flaherty C, Taketo T, Culty M, Fok KL, Wing SS. Ubiquitin Ligase Huwe1 Modulates Spermatogenesis by Regulating Spermatogonial Differentiation and Entry into Meiosis. Sci Rep 2017; 7:17759. [PMID: 29259204 PMCID: PMC5736635 DOI: 10.1038/s41598-017-17902-0] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2017] [Accepted: 12/01/2017] [Indexed: 12/02/2022] Open
Abstract
Spermatogenesis consists of a series of highly regulated processes that include mitotic proliferation, meiosis and cellular remodeling. Although alterations in gene expression are well known to modulate spermatogenesis, posttranscriptional mechanisms are less well defined. The ubiquitin proteasome system plays a significant role in protein turnover and may be involved in these posttranscriptional mechanisms. We previously identified ubiquitin ligase Huwe1 in the testis and showed that it can ubiquitinate histones. Since modulation of histones is important at many steps in spermatogenesis, we performed a complete characterization of the functions of Huwe1 in this process by examining the effects of its inactivation in the differentiating spermatogonia, spermatocytes and spermatids. Inactivation of Huwe1 in differentiating spermatogonia led to their depletion and formation of fewer pre-leptotene spermatocytes. The cell degeneration was associated with an accumulation of DNA damage response protein γH2AX, impaired downstream signalling and apoptosis. Inactivation of Huwe1 in spermatocytes indicated that Huwe1 is not essential for meiosis and spermiogenesis, but can result in accumulation of γH2AX. Collectively, these results provide a comprehensive survey of the functions of Huwe1 in spermatogenesis and reveal Huwe1’s critical role as a modulator of the DNA damage response pathway in the earliest steps of spermatogonial differentiation.
Collapse
Affiliation(s)
- Rohini Bose
- The Research Institute of the McGill University Health Centre, Montréal, Québec, Canada.,Department of Medicine, McGill University, Montréal, Québec, Canada
| | - Kai Sheng
- The Research Institute of the McGill University Health Centre, Montréal, Québec, Canada.,Department of Medicine, McGill University, Montréal, Québec, Canada
| | - Adel R Moawad
- The Research Institute of the McGill University Health Centre, Montréal, Québec, Canada.,Department of Surgery, McGill University, Montréal, Québec, Canada.,Department of Theriogenology, Faculty of Veterinary Medicine, Cairo University, Giza, Egypt
| | - Gurpreet Manku
- The Research Institute of the McGill University Health Centre, Montréal, Québec, Canada.,Department of Medicine, McGill University, Montréal, Québec, Canada.,Department of Pharmacology and Therapeutics, McGill University, Montréal, Québec, Canada
| | - Cristian O'Flaherty
- The Research Institute of the McGill University Health Centre, Montréal, Québec, Canada.,Department of Surgery, McGill University, Montréal, Québec, Canada.,Department of Pharmacology and Therapeutics, McGill University, Montréal, Québec, Canada
| | - Teruko Taketo
- The Research Institute of the McGill University Health Centre, Montréal, Québec, Canada.,Department of Surgery, McGill University, Montréal, Québec, Canada.,Department of Obstetrics and Gynecology, McGill University, Montréal, Québec, Canada.,Department of Biology, McGill University, Montréal, Québec, Canada
| | - Martine Culty
- The Research Institute of the McGill University Health Centre, Montréal, Québec, Canada.,Department of Medicine, McGill University, Montréal, Québec, Canada.,Dept. of Pharmacology, University of Southern California, Los Angeles, California, USA
| | - Kin Lam Fok
- The Research Institute of the McGill University Health Centre, Montréal, Québec, Canada.,Department of Medicine, McGill University, Montréal, Québec, Canada.,Epithelial Cell Biology Research Center, School of Biomedical Sciences, The Faculty of Medicine, The Chinese University of Hong Kong, Sha Tin, Hong Kong.,Shenzhen Research Institute, The Chinese University of Hong Kong - Shenzhen, Shenzhen, China
| | - Simon S Wing
- The Research Institute of the McGill University Health Centre, Montréal, Québec, Canada. .,Department of Medicine, McGill University, Montréal, Québec, Canada.
| |
Collapse
|
19
|
Fok KL, Bose R, Sheng K, Chang CW, Katz-Egorov M, Culty M, Su S, Yang M, Ruan YC, Chan HC, Iavarone A, Lasorella A, Cencic R, Pelletier J, Nagano M, Xu W, Wing SS. Huwe1 Regulates the Establishment and Maintenance of Spermatogonia by Suppressing DNA Damage Response. Endocrinology 2017; 158:4000-4016. [PMID: 28938460 DOI: 10.1210/en.2017-00396] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/23/2017] [Accepted: 08/21/2017] [Indexed: 11/19/2022]
Abstract
Spermatogenesis is sustained by a heterogeneous population of spermatogonia that includes the spermatogonial stem cells. However, the mechanisms underlying their establishment from gonocyte embryonic precursors and their maintenance thereafter remain largely unknown. In this study, we report that inactivation of the ubiquitin ligase Huwe1 in male germ cells in mice led to the degeneration of spermatogonia in neonates and resulted in a Sertoli cell-only phenotype in the adult. Huwe1 knockout gonocytes showed a decrease in mitotic re-entry, which inhibited their transition to spermatogonia. Inactivation of Huwe1 in primary spermatogonial culture or the C18-4 cell line resulted in cell degeneration. Degeneration of Huwe1 knockout spermatogonia was associated with an increased level of histone H2AX and an elevated DNA damage response that led to apparent mitotic catastrophe but not apoptosis or senescence. Blocking this increase in H2AX prevented the degeneration of Huwe1-depleted cells. Taken together, these results reveal a previously undefined role of Huwe1 in orchestrating the physiological DNA damage response in the male germline that contributes to the establishment and maintenance of spermatogonia.
Collapse
Affiliation(s)
- Kin Lam Fok
- Department of Medicine, McGill University and McGill University Health Centre Research Institute, Montreal, Quebec H4A 3J1, Canada
- Epithelial Cell Biology Research Center, School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong
| | - Rohini Bose
- Department of Medicine, McGill University and McGill University Health Centre Research Institute, Montreal, Quebec H4A 3J1, Canada
| | - Kai Sheng
- Department of Medicine, McGill University and McGill University Health Centre Research Institute, Montreal, Quebec H4A 3J1, Canada
| | - Ching-Wen Chang
- Department of Obstetrics and Gynecology, McGill University and McGill University Health Centre, Montreal, Quebec H4A 3J1, Canada
| | - Mira Katz-Egorov
- Department of Medicine, McGill University and McGill University Health Centre Research Institute, Montreal, Quebec H4A 3J1, Canada
| | - Martine Culty
- Department of Medicine, McGill University and McGill University Health Centre Research Institute, Montreal, Quebec H4A 3J1, Canada
| | - Sicheng Su
- Sichuan University-The Chinese University of Hong Kong Joint Laboratory for Reproductive Medicine, Sichuan University, Chengdu, Sichuan 610041, China
| | - Ming Yang
- Sichuan University-The Chinese University of Hong Kong Joint Laboratory for Reproductive Medicine, Sichuan University, Chengdu, Sichuan 610041, China
| | - Ye Chun Ruan
- Epithelial Cell Biology Research Center, School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong
| | - Hsiao Chang Chan
- Epithelial Cell Biology Research Center, School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong
| | - Antonio Iavarone
- Institute for Cancer Genetics, Columbia University Medical Center, New York, New York 10032
| | - Anna Lasorella
- Institute for Cancer Genetics, Columbia University Medical Center, New York, New York 10032
| | - Regina Cencic
- Department of Biochemistry, McGill University, Montreal, Quebec H3G 1Y6, Canada
| | - Jerry Pelletier
- Department of Biochemistry, McGill University, Montreal, Quebec H3G 1Y6, Canada
| | - Makoto Nagano
- Department of Medicine, McGill University and McGill University Health Centre Research Institute, Montreal, Quebec H4A 3J1, Canada
- Department of Obstetrics and Gynecology, McGill University and McGill University Health Centre, Montreal, Quebec H4A 3J1, Canada
| | - Wenming Xu
- Sichuan University-The Chinese University of Hong Kong Joint Laboratory for Reproductive Medicine, Sichuan University, Chengdu, Sichuan 610041, China
- Department of Obstetrics and Gynecology, West China Second University Hospital, Sichuan University, Chengdu, Sichuan 610041, China
| | - Simon S Wing
- Department of Medicine, McGill University and McGill University Health Centre Research Institute, Montreal, Quebec H4A 3J1, Canada
| |
Collapse
|
20
|
Fukunaga H, Butterworth KT, Yokoya A, Ogawa T, Prise KM. Low-dose radiation-induced risk in spermatogenesis. Int J Radiat Biol 2017; 93:1291-1298. [DOI: 10.1080/09553002.2017.1355579] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Affiliation(s)
- Hisanori Fukunaga
- Centre for Cancer Research and Cell Biology, Queen’s University Belfast, Belfast, UK
| | - Karl T. Butterworth
- Centre for Cancer Research and Cell Biology, Queen’s University Belfast, Belfast, UK
| | - Akinari Yokoya
- Tokai Quantum Beam Science Center, National Institutes for Quantum and Radiological Science and Technology, Tokai, Japan
| | - Takehiko Ogawa
- Institute of Molecular Medicine and Life Science, Yokohama City University Association of Medical Science, Yokohama, Japan
| | - Kevin M. Prise
- Centre for Cancer Research and Cell Biology, Queen’s University Belfast, Belfast, UK
| |
Collapse
|
21
|
Beaud H, van Pelt A, Delbes G. Doxorubicin and vincristine affect undifferentiated rat spermatogonia. Reproduction 2017; 153:725-735. [DOI: 10.1530/rep-17-0005] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2017] [Revised: 02/25/2017] [Accepted: 03/03/2017] [Indexed: 11/08/2022]
Abstract
Anticancer drugs, such as alkylating agents, can affect male fertility by targeting the DNA of proliferative spermatogonial stem cells (SSC). Therefore, to reduce such side effects, other chemotherapeutics are used. However, less is known about their potential genotoxicity on SSC. Moreover, DNA repair mechanisms in SSC are poorly understood. To model treatments deprived of alkylating agents that are commonly used in cancer treatment, we tested the impact of exposure to doxorubicin and vincristine, alone or in combination (MIX), on a rat spermatogonial cell line with SSC characteristics (GC-6spg). Vincristine alone induced a cell cycle arrest and cell death without genotoxic impact. On the other hand, doxorubicin and the MIX induced a dose-dependent cell death. More importantly, doxorubicin and the MIX induced DNA breaks, measured by the COMET assay, at a non-cytotoxic dose. To elucidate which DNA repair pathway is activated in spermatogonia after exposure to doxorubicin, we screened the expression of 75 genes implicated in DNA repair. Interestingly, all were expressed constitutively in GC-6spg, suggesting great potential to respond to genotoxic stress. Doxorubicin treatments affected the expression of 16 genes (>1.5 fold change;P < 0.05) involved in cell cycle, base/nucleotide excision repair, homologous recombination and non-homologous end joining (NHEJ). The significant increase in CDKN1A and XRCC1 suggest a cell cycle arrest and implies an alternative NHEJ pathway in response to doxorubicin-induced DNA breaks. Together, our results support the idea that undifferentiated spermatogonia have the ability to respond to DNA injury from chemotherapeutic compounds and escape DNA break accumulation.
Collapse
|
22
|
Analysis of DNA polymerase ν function in meiotic recombination, immunoglobulin class-switching, and DNA damage tolerance. PLoS Genet 2017; 13:e1006818. [PMID: 28570559 PMCID: PMC5472330 DOI: 10.1371/journal.pgen.1006818] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2017] [Revised: 06/15/2017] [Accepted: 05/13/2017] [Indexed: 11/20/2022] Open
Abstract
DNA polymerase ν (pol ν), encoded by the POLN gene, is an A-family DNA polymerase in vertebrates and some other animal lineages. Here we report an in-depth analysis of pol ν–defective mice and human cells. POLN is very weakly expressed in most tissues, with the highest relative expression in testis. We constructed multiple mouse models for Poln disruption and detected no anatomic abnormalities, alterations in lifespan, or changed causes of mortality. Mice with inactive Poln are fertile and have normal testis morphology. However, pol ν–disrupted mice have a modestly reduced crossover frequency at a meiotic recombination hot spot harboring insertion/deletion polymorphisms. These polymorphisms are suggested to generate a looped-out primer and a hairpin structure during recombination, substrates on which pol ν can operate. Pol ν-defective mice had no alteration in DNA end-joining during immunoglobulin class-switching, in contrast to animals defective in the related DNA polymerase θ (pol θ). We examined the response to DNA crosslinking agents, as purified pol ν has some ability to bypass major groove peptide adducts and residues of DNA crosslink repair. Inactivation of Poln in mouse embryonic fibroblasts did not alter cellular sensitivity to mitomycin C, cisplatin, or aldehydes. Depletion of POLN from human cells with shRNA or siRNA did not change cellular sensitivity to mitomycin C or alter the frequency of mitomycin C-induced radial chromosomes. Our results suggest a function of pol ν in meiotic homologous recombination in processing specific substrates. The restricted and more recent evolutionary appearance of pol ν (in comparison to pol θ) supports such a specialized role. The work described here fills a current gap in the study of the 16 known DNA polymerases in vertebrate genomes. Until now, experiments with genetically disrupted mice have been reported for all but pol ν, encoded by the POLN gene. To intensively analyze the role of mammalian pol ν we generated multiple Poln-deficient murine models. We discovered that Poln is uniquely upregulated during testicular development and that it is enriched in spermatocytes. This, and phylogenetic analysis indicate a testis-specific function. We observed a modest reduction in meiotic recombination at a recombination hotspot in Poln-deficient mice. Pol ν has been suggested to function in DNA crosslink repair. However, we found no increased DNA crosslink sensitivity in Poln-deficient mice or POLN-depleted human cells. This is a major difference from some previous findings, and we support our conclusion by multiple experimental approaches, and by the very low or absent expression of functional pol ν in mammalian somatic cells. The present work represents the first description and comprehensive analysis of mice deficient in pol ν, and the first thorough phenotypic analysis in human cells.
Collapse
|
23
|
Meier MJ, O’Brien JM, Beal MA, Allan B, Yauk CL, Marchetti F. In Utero Exposure to Benzo[a]Pyrene Increases Mutation Burden in the Soma and Sperm of Adult Mice. ENVIRONMENTAL HEALTH PERSPECTIVES 2017; 125:82-88. [PMID: 27448386 PMCID: PMC5226697 DOI: 10.1289/ehp211] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/23/2016] [Revised: 06/13/2016] [Accepted: 06/23/2016] [Indexed: 05/03/2023]
Abstract
BACKGROUND Mosaicism, the presence of genetically distinct cell populations within an organism, has emerged as an important contributor to disease. Mutational events occurring during embryonic development can cause mosaicism in any tissue, but the influence of environmental factors on levels of mosaicism is unclear. OBJECTIVES We investigated whether in utero exposure to the widespread environmental mutagen benzo[a]pyrene (BaP) has an impact on the burden and distribution of mutations in adult mice. METHODS We used the Muta™Mouse transgenic rodent model to quantify and characterize mutations in the offspring of pregnant mice exposed to BaP during postconception days 7 through 16, covering the major period of organogenesis in mice. Next-generation DNA sequencing was then used to determine the spectrum of mutations induced in adult mice that were exposed to BaP during fetal development. RESULTS Mutation frequency was significantly increased in the bone marrow, liver, brain, and sperm of first filial generation (F1) males. Developing embryos accumulated more mutations and exhibited higher proportions of mosaicism than exposed adults, particularly in the brain. Decreased sperm count and motility revealed additional negative impacts on the reproductive function of F1 males. CONCLUSION In utero exposure to environmental mutagens contributes to somatic and germline mosaicism, permanently affecting both the genetic health of the F1 and the population gene pool. Citation: Meier MJ, O'Brien JM, Beal MA, Allan B, Yauk CL, Marchetti F. 2017. In utero exposure to benzo[a]pyrene increases mutation burden in the soma and sperm of adult mice. Environ Health Perspect 125:82-88; http://dx.doi.org/10.1289/EHP211.
Collapse
Affiliation(s)
- Matthew J. Meier
- Environmental Health Science and Research Bureau, Health Canada, Ottawa, Ontario, Canada
| | - Jason M. O’Brien
- Environmental Health Science and Research Bureau, Health Canada, Ottawa, Ontario, Canada
| | - Marc A. Beal
- Environmental Health Science and Research Bureau, Health Canada, Ottawa, Ontario, Canada
- Department of Biology, Carleton University, Ottawa, Ontario, Canada
| | - Beverly Allan
- Environmental Health Science and Research Bureau, Health Canada, Ottawa, Ontario, Canada
- Department of Biology, Carleton University, Ottawa, Ontario, Canada
| | - Carole L. Yauk
- Environmental Health Science and Research Bureau, Health Canada, Ottawa, Ontario, Canada
| | - Francesco Marchetti
- Environmental Health Science and Research Bureau, Health Canada, Ottawa, Ontario, Canada
- Address correspondence to F. Marchetti, Environmental Health Science and Research Bureau, Health Canada, 50 Colombine Driveway, Ottawa, Ontario, K1A 0K9, Canada. Telephone: 1-613-9573137. E-mail:
| |
Collapse
|
24
|
Marjault HB, Allemand I. Consequences of irradiation on adult spermatogenesis: Between infertility and hereditary risk. MUTATION RESEARCH-REVIEWS IN MUTATION RESEARCH 2016; 770:340-348. [DOI: 10.1016/j.mrrev.2016.07.004] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/19/2016] [Revised: 07/15/2016] [Accepted: 07/18/2016] [Indexed: 12/31/2022]
|
25
|
Abstract
DNA damage response is required for male fertility. DNA damage repair mediates recombination between homologous chromosomes in meiotic prophase, which is essential for proper chromosome segregation during meiotic division. Interestingly, some DNA damage response proteins are also required for the survival of premeiotic germ cells, but their roles in these cells are still unclear. CHFR was recently shown to participate in DNA damage response, but it remains to be established if CHFR is required for male fertility. In this study, we characterized Chfr knockout male mice and found that around 30% of them were infertile. The onset of spermatogenesis was delayed and there was significant increase in apoptosis in premeiotic germ cells. This resulted in complete loss of germ cells in testes in 3 months and azoospermia in these mice. We further demonstrated that ATM activation was compromised in the testes of these mice. Therefore, CHFR is important for the survival of male premeiotic germ cells, which is likely through maintaining genomic stability in spermatogonial stem cells.
Collapse
Affiliation(s)
- Lin-Yu Lu
- a Key Laboratory of Reproductive Genetics; Ministry of Education and Women's Reproductive Health Laboratory of Zhejiang Province; Women's Hospital; School of Medicine; Zhejiang University ; Hangzhou , Zhejiang , China.,b Institute of Translational Medicine; Zhejiang University ; Hangzhou , Zhejiang , China
| | - Xiaochun Yu
- c Department of Cancer Genetics and Epigenetics ; Beckman Research Institute; City of Hope ; Duarte , CA USA
| |
Collapse
|
26
|
Lu J, Li H, Baccei A, Sasaki T, Gilbert DM, Lerou PH. Influence of ATM-Mediated DNA Damage Response on Genomic Variation in Human Induced Pluripotent Stem Cells. Stem Cells Dev 2016; 25:740-7. [PMID: 26935587 DOI: 10.1089/scd.2015.0393] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Genome instability is a potential limitation to the research and therapeutic application of induced pluripotent stem cells (iPSCs). Observed genomic variations reflect the combined activities of DNA damage, cellular DNA damage response (DDR), and selection pressure in culture. To understand the contribution of DDR on the distribution of copy number variations (CNVs) in iPSCs, we mapped CNVs of iPSCs with mutations in the central DDR gene ATM onto genome organization landscapes defined by genome-wide replication timing profiles. We show that following reprogramming the early and late replicating genome is differentially affected by CNVs in ATM-deficient iPSCs relative to wild-type iPSCs. Specifically, the early replicating regions had increased CNV losses during retroviral (RV) reprogramming. This differential CNV distribution was not present after later passage or after episomal reprogramming. Comparison of different reprogramming methods in the setting of defective DDR reveals unique vulnerability of early replicating open chromatin to RV vectors.
Collapse
Affiliation(s)
- Junjie Lu
- 1 Department of Pediatric Newborn Medicine and Division of Genetics, Department of Medicine, Brigham and Women's Hospital , Harvard Stem Cell Institute, Harvard Medical School, Boston, Massachusetts
| | - Hu Li
- 2 Department of Molecular Pharmacology and Experimental Therapeutics, Center for Individualized Medicine , Mayo Clinic, Rochester, Minnesota
| | - Anna Baccei
- 1 Department of Pediatric Newborn Medicine and Division of Genetics, Department of Medicine, Brigham and Women's Hospital , Harvard Stem Cell Institute, Harvard Medical School, Boston, Massachusetts
| | - Takayo Sasaki
- 3 Department of Biological Sciences, Florida State University , Tallahassee, Florida
| | - David M Gilbert
- 3 Department of Biological Sciences, Florida State University , Tallahassee, Florida
| | - Paul H Lerou
- 1 Department of Pediatric Newborn Medicine and Division of Genetics, Department of Medicine, Brigham and Women's Hospital , Harvard Stem Cell Institute, Harvard Medical School, Boston, Massachusetts.,4 Division of Neonatology, Department of Pediatrics, Massachusetts General Hospital , Boston, Massachusetts
| |
Collapse
|
27
|
Jacobs KM, Misri S, Meyer B, Raj S, Zobel CL, Sleckman BP, Hallahan DE, Sharma GG. Unique epigenetic influence of H2AX phosphorylation and H3K56 acetylation on normal stem cell radioresponses. Mol Biol Cell 2016; 27:1332-45. [PMID: 26941327 PMCID: PMC4831886 DOI: 10.1091/mbc.e16-01-0017] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2016] [Accepted: 02/22/2016] [Indexed: 01/08/2023] Open
Abstract
Normal stem cells from tissues often exhibiting radiation injury are highly radiosensitive and exhibit a muted DNA damage response, in contrast to differentiated progeny. These radioresponses can be attributed to unique epigenetic regulation in stem cells, identifying potential therapeutic targets for radioprotection. Normal tissue injury resulting from cancer radiotherapy is often associated with diminished regenerative capacity. We examined the relative radiosensitivity of normal stem cell populations compared with non–stem cells within several radiosensitive tissue niches and culture models. We found that these stem cells are highly radiosensitive, in contrast to their isogenic differentiated progeny. Of interest, they also exhibited a uniquely attenuated DNA damage response (DDR) and muted DNA repair. Whereas stem cells exhibit reduced ATM activation and ionizing radiation–induced foci, they display apoptotic pannuclear H2AX-S139 phosphorylation (γH2AX), indicating unique radioresponses. We also observed persistent phosphorylation of H2AX-Y142 along the DNA breaks in stem cells, which promotes apoptosis while inhibiting DDR signaling. In addition, down-regulation of constitutively elevated histone-3 lysine-56 acetylation (H3K56ac) in stem cells significantly decreased their radiosensitivity, restored DDR function, and increased survival, signifying its role as a key contributor to stem cell radiosensitivity. These results establish that unique epigenetic landscapes affect cellular heterogeneity in radiosensitivity and demonstrate the nonubiquitous nature of radiation responses. We thus elucidate novel epigenetic rheostats that promote ionizing radiation hypersensitivity in various normal stem cell populations, identifying potential molecular targets for pharmacological radioprotection of stem cells and hopefully improving the efficacy of future cancer treatment.
Collapse
Affiliation(s)
- Keith M Jacobs
- Department of Radiation Oncology, Cancer Biology Division, Washington University School of Medicine, St. Louis, MO 63108
| | - Sandeep Misri
- Department of Radiation Oncology, Cancer Biology Division, Washington University School of Medicine, St. Louis, MO 63108
| | - Barbara Meyer
- Department of Radiation Oncology, Cancer Biology Division, Washington University School of Medicine, St. Louis, MO 63108
| | - Suyash Raj
- Department of Radiation Oncology, Cancer Biology Division, Washington University School of Medicine, St. Louis, MO 63108
| | - Cheri L Zobel
- Department of Radiation Oncology, Cancer Biology Division, Washington University School of Medicine, St. Louis, MO 63108
| | - Barry P Sleckman
- Siteman Cancer Center, Washington University School of Medicine, St. Louis, MO 63108 Department of Pathology, Laboratory and Genomic Medicine, Washington University School of Medicine, St. Louis, MO 63108
| | - Dennis E Hallahan
- Department of Radiation Oncology, Cancer Biology Division, Washington University School of Medicine, St. Louis, MO 63108 Siteman Cancer Center, Washington University School of Medicine, St. Louis, MO 63108
| | - Girdhar G Sharma
- Department of Radiation Oncology, Cancer Biology Division, Washington University School of Medicine, St. Louis, MO 63108 Siteman Cancer Center, Washington University School of Medicine, St. Louis, MO 63108
| |
Collapse
|
28
|
Ahmed EA, Scherthan H, de Rooij DG. DNA Double Strand Break Response and Limited Repair Capacity in Mouse Elongated Spermatids. Int J Mol Sci 2015; 16:29923-35. [PMID: 26694360 PMCID: PMC4691157 DOI: 10.3390/ijms161226214] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2015] [Revised: 11/14/2015] [Accepted: 12/10/2015] [Indexed: 12/31/2022] Open
Abstract
Spermatids are extremely sensitive to genotoxic exposures since during spermiogenesis only error-prone non homologous end joining (NHEJ) repair pathways are available. Hence, genomic damage may accumulate in sperm and be transmitted to the zygote. Indirect, delayed DNA fragmentation and lesions associated with apoptotic-like processes have been observed during spermatid elongation, 27 days after irradiation. The proliferating spermatogonia and early meiotic prophase cells have been suggested to retain a memory of a radiation insult leading later to this delayed fragmentation. Here, we used meiotic spread preparations to localize phosphorylate histone H2 variant (γ-H2AX) foci marking DNA double strand breaks (DSBs) in elongated spermatids. This technique enabled us to determine the background level of DSB foci in elongated spermatids of RAD54/RAD54B double knockout (dko) mice, severe combined immunodeficiency SCID mice, and poly adenosine diphosphate (ADP)-ribose polymerase 1 (PARP1) inhibitor (DPQ)-treated mice to compare them with the appropriate wild type controls. The repair kinetics data and the protein expression patterns observed indicate that the conventional NHEJ repair pathway is not available for elongated spermatids to repair the programmed and the IR-induced DSBs, reflecting the limited repair capacity of these cells. However, although elongated spermatids express the proteins of the alternative NHEJ, PARP1-inhibition had no effect on the repair kinetics after IR, suggesting that DNA damage may be passed onto sperm. Finally, our genetic mutant analysis suggests that an incomplete or defective meiotic recombinational repair of Spo11-induced DSBs may lead to a carry-over of the DSB damage or induce a delayed nuclear fragmentation during the sensitive programmed chromatin remodeling occurring in elongated spermatids.
Collapse
Affiliation(s)
- Emad A Ahmed
- Laboratory of Immunology and Molecular Physiology, Department of Zoology, Faculty of Science, Assiut University, Assiut 71516, Egypt.
- Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield S10 2TN, UK.
| | - Harry Scherthan
- Institute für Radiobiologie der Bundeswehr in Verb. mit der University, Ulm, Neuherbergstr, 11, Munich D-80937, Germany.
| | - Dirk G de Rooij
- Reproductive Biology Group, Division of Developmental Biology, Department of Biology, Faculty of Science, Utrecht University, Utrecht 3584CM, The Netherlands.
| |
Collapse
|
29
|
Persistent DNA Damage in Spermatogonial Stem Cells After Fractionated Low-Dose Irradiation of Testicular Tissue. Int J Radiat Oncol Biol Phys 2015; 92:1123-1131. [DOI: 10.1016/j.ijrobp.2015.04.033] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2015] [Revised: 04/15/2015] [Accepted: 04/21/2015] [Indexed: 11/22/2022]
|
30
|
Gou Q, Xie Y, Liu L, Xie K, Wu Y, Wang Q, Wang Z, Li P. Downregulation of MDC1 and 53BP1 by short hairpin RNA enhances radiosensitivity in laryngeal carcinoma cells. Oncol Rep 2015; 34:251-7. [PMID: 25976740 DOI: 10.3892/or.2015.3980] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2014] [Accepted: 02/10/2015] [Indexed: 02/05/2023] Open
Abstract
DNA double-strand breaks (DSBs) induced by ionizing radiation (IR) are among the most cytotoxic types of DNA damage. The DNA damage response (DDR) may be a reason for the cancer cell resistance to radiotherapy using IR. Identified as critical upstream mediators of the phosphorylation of ataxia telangiectasia-mutated (ATM) pathway, mediator of DNA damage checkpoint 1 (MDC1) and p53-binding proteins 1 (53BP1) may affect the radiosensitivity of tumor cells. In the present study, we generated two HEP-2 cell lines with a stable knockdown of MDC1 or 53BP1 with short hairpin RNA (shRNA), respectively, and investigated the effect of MDC1 and 53BP1 on cell radiosensitivity, cell cycle distribution and the formation of cell foci. Downregulation of the two proteins reduced the number of clonogenic cells that treated with IR. Accumulation of G2/M phase cells was detected after the MDC1 and 53BP1 downregulation. These results indicated that the expression of MDC1 or 53BP1 limited tumor cell sensitivity to radiotherapy and may play an important role in the DNA repair progression. Furthermore, the MDC1 foci was identified and presented in the 53BP1-inhibited cells. By contrast, the 53BP1 foci was absent from the MDC1-inhibited cells. The results confirmed that the recruitment of 53BP1 into the foci occurred in an MDC1-dependent manner.
Collapse
Affiliation(s)
- Qiheng Gou
- State Key Laboratory of Biotherapy/Collaborative Innovation Center of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, P.R. China
| | - Yuxin Xie
- Cancer Center, West China Hospital, West China Medical School, Sichuan University, Chengdu, Sichuan 610041, P.R. China
| | - Lei Liu
- Cancer Center, West China Hospital, West China Medical School, Sichuan University, Chengdu, Sichuan 610041, P.R. China
| | - Keqi Xie
- Department of Anesthesiology, Mianyang Central Hospital, Mianyang, Sichuan 621000, P.R. China
| | - Yanxia Wu
- Laboratory of Molecular Diagnosis of Cancer, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, P.R. China
| | - Qianqian Wang
- Cancer Center, West China Hospital, West China Medical School, Sichuan University, Chengdu, Sichuan 610041, P.R. China
| | - Zhu Wang
- Laboratory of Molecular Diagnosis of Cancer, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, P.R. China
| | - Ping Li
- Cancer Center, West China Hospital, West China Medical School, Sichuan University, Chengdu, Sichuan 610041, P.R. China
| |
Collapse
|
31
|
Pellestor F, Gatinois V, Puechberty J, Geneviève D, Lefort G. Chromothripsis: potential origin in gametogenesis and preimplantation cell divisions. A review. Fertil Steril 2014; 102:1785-96. [PMID: 25439810 DOI: 10.1016/j.fertnstert.2014.09.006] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2014] [Revised: 09/04/2014] [Accepted: 09/04/2014] [Indexed: 12/24/2022]
Abstract
OBJECTIVE To review the discovery of chromothripsis and analyze its impact on human reproduction. DESIGN Database and literature analysis. SETTING University hospital. PATIENT(S) Carriers of massive and complex chromosomal rearrangements. INTERVENTION(S) Cytogenetic analysis and molecular testing (fluorescence in situ hybridization, microarray, whole-genome sequencing). MAIN OUTCOME MEASURE(S) Chromothripsis occurrence in human gametes and preimplantation embryos, with regard to the potential causative mechanisms described in literature. RESULT(S) Databases were searched for the literature published up to March 2014. Chromothripsis is characterized by the shattering of one (or a few) chromosome segments followed by a haphazard reassembly of the fragments generated, arising through a single initial catastrophic event. Several mechanisms involving abortive apoptosis, telomere erosion, mitotic errors, micronuclei formation, and p53 inactivation might cause chromothripsis. The remarkable point is that all these plausible mechanisms have been identified in the field of human reproduction as causal factors for reproductive failures and the genesis of chromosomal abnormalities. Specific features of gametogenesis and early embryonic development such as the weakness of cell cycle and mitosis checkpoints and the rapid kinetics of division in germ cells and early cleavage embryos may contribute to the emergence of chromothripsis. CONCLUSION(S) The discovery of this new class of massive chromosomal rearrangement has deeply modified our understanding on the genesis of complex genomic rearrangements. Data presented in this review support the assumption that chromothripsis could operate in human germlines and during early embryonic development. Chromothripsis might arise more frequently than previously thought in both gametogenesis and early human embryogenesis.
Collapse
Affiliation(s)
- Franck Pellestor
- Laboratory of Chromosomal Genetics, Department of Medical Genetics, Arnaud de Villeneuve Hospital, Montpellier CHRU, Montpellier, France; INSERM Unit Plasticity of the Genome and Aging, Institute of Functional Genomics, Montpellier, France.
| | - Vincent Gatinois
- Laboratory of Chromosomal Genetics, Department of Medical Genetics, Arnaud de Villeneuve Hospital, Montpellier CHRU, Montpellier, France; INSERM Unit Plasticity of the Genome and Aging, Institute of Functional Genomics, Montpellier, France
| | - Jacques Puechberty
- Laboratory of Chromosomal Genetics, Department of Medical Genetics, Arnaud de Villeneuve Hospital, Montpellier CHRU, Montpellier, France
| | - David Geneviève
- Laboratory of Chromosomal Genetics, Department of Medical Genetics, Arnaud de Villeneuve Hospital, Montpellier CHRU, Montpellier, France
| | - Geneviève Lefort
- Laboratory of Chromosomal Genetics, Department of Medical Genetics, Arnaud de Villeneuve Hospital, Montpellier CHRU, Montpellier, France
| |
Collapse
|
32
|
The Trp53-Trp53inp1-Tnfrsf10b pathway regulates the radiation response of mouse spermatogonial stem cells. Stem Cell Reports 2014; 3:676-89. [PMID: 25358794 PMCID: PMC4223695 DOI: 10.1016/j.stemcr.2014.08.006] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2014] [Revised: 08/05/2014] [Accepted: 08/06/2014] [Indexed: 12/22/2022] Open
Abstract
Germ cells are thought to exhibit a unique DNA damage response that differs from that of somatic stem cells, and previous studies suggested that Trp53 is not involved in the survival of spermatogonial stem cells (SSCs) after irradiation. Here, we report a critical role for the Trp53-Trp53inp1-Tnfrsf10b pathway during radiation-induced SSC apoptosis. Spermatogonial transplantation revealed that Trp53 deficiency increased the survival of SSCs after irradiation. Although Bbc3, a member of the intrinsic apoptotic pathway, was implicated in apoptosis of germ and somatic stem cells, Bbc3 depletion inhibited apoptosis in committed spermatogonia, but not in SSCs. In contrast, inhibition of Tnfrsf10b, an extrinsic apoptosis regulator, rescued SSCs. Tnfrsf10b, whose deficiency protected SSCs, was upregulated by Trp53inp1 upon irradiation. These results suggest that the Trp53-Trp53inp1-Tnfrsf10b pathway responds to genotoxic damage in SSCs and that stem and progenitor cells exhibit distinct DNA damage responses in self-renewing tissue. Trp53 induces radiation-induced apoptosis of spermatogonial stem cells (SSCs) Bbc3 induces radiation-induced apoptosis of spermatogonial progenitors Tnfsf10 is induced in spermatogonia and the SSC microenvironment Trp53inp1 upregulates Tnfrsf10b and induces SSC apoptosis upon irradiation
Collapse
|
33
|
Phospho-Cdc25 correlates with activating G2/M checkpoint in mouse zygotes fertilized with hydrogen peroxide-treated mouse sperm. Mol Cell Biochem 2014; 396:41-8. [PMID: 25012723 DOI: 10.1007/s11010-014-2140-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2014] [Accepted: 06/23/2014] [Indexed: 02/05/2023]
Abstract
The presence of oxidative stress in sperm cryopreservation induces sperm DNA damage. Our previous study has discovered that γH2AX, the DNA-damaged marker, was activated in the early mouse embryos fertilized with hydrogen peroxide (H2O2)-treated sperm. Furthermore, we found that checkpoint proteins ATM and Chk1 were phosphorylated and activated in the early mouse embryos. On the basis of previous researches, we examined the effects of sperm DNA damage on cell cycle arrest in mouse zygotes fertilized with H2O2-treated sperm. Development of fertilized eggs arrested at the PN disappearance stage. At 19 and 24 hours post-insemination (hpi), the percentage of zygotes at the PN disappearance stage was higher in H2O2-treated group compared to the control group. Immunofluorescence staining revealed Phospho-Cdc25C (Ser216) and Phospho-Cdc25B (Ser323) in or surrounding a single pronucleus, following insemination with H2O2-treated sperm. Our study suggests that fertilization with DNA-damaged sperm results in cell cycle arrest mediated by G2/M checkpoint activation in one of the pronuclei in mouse zygotes fertilized with H2O2-treated sperm; Phospho-Cdc25C and Phospho-Cdc25B correlate with activating G2/M checkpoint in zygotes fertilized with H2O2-treated sperm.
Collapse
|
34
|
Rad54 is required for the normal development of male and female germ cells and contributes to the maintainance of their genome integrity after genotoxic stress. Cell Death Dis 2013; 4:e774. [PMID: 23949223 PMCID: PMC3763443 DOI: 10.1038/cddis.2013.281] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2013] [Revised: 06/25/2013] [Accepted: 07/02/2013] [Indexed: 12/31/2022]
Abstract
Rad54 is an important factor in the homologous recombination pathway of DNA double-strand break repair. However, Rad54 knockout (KO) mice do not exhibit overt phenotypes at adulthood, even when exposed to radiation. In this study, we show that in Rad54 KO mouse the germline is actually altered. Compared with the wild-type (WT) animals, these mice have less premeiotic germ cells. This germ cell loss is found as early as in E11.5 embryos, suggesting an early failure during mutant primordial germ cells development. Both testicular and ovarian KO germ cells exhibited high radiation sensitivity leading to a long-term gametogenesis defect at adulthood. The KO female germline was particularly affected displaying decreased litter size or sterility. Spermatogenesis recovery after irradiation was slower and incomplete in Rad54 KO mice compared with that of WT mice, suggesting that loss of germ stem cell precursors is not fully compensated along the successive rounds of spermatogenesis. Finally, spermatogenesis recovery after postnatal irradiation is in part regulated by glial-cell-line-derived neurotrophic factor (GDNF) in KO but not in irradiated WT mice, suggesting that Sertoli cell GDNF production is stimulated upon substantial germ cell loss only. Our findings suggest that Rad54 has a key function in maintaining genomic integrity of the developing germ cells.
Collapse
|
35
|
Accumulation of DNA damage-induced chromatin alterations in tissue-specific stem cells: the driving force of aging? PLoS One 2013; 8:e63932. [PMID: 23691119 PMCID: PMC3656879 DOI: 10.1371/journal.pone.0063932] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2012] [Accepted: 04/08/2013] [Indexed: 01/11/2023] Open
Abstract
Accumulation of DNA damage leading to stem cell exhaustion has been proposed to be a principal mechanism of aging. Using 53BP1-foci as a marker for DNA double-strand breaks (DSBs), hair follicle stem cells (HFSCs) in mouse epidermis were analyzed for age-related DNA damage response (DDR). We observed increasing amounts of 53BP1-foci during the natural aging process independent of telomere shortening and after protracted low-dose radiation, suggesting substantial accumulation of DSBs in HFSCs. Electron microscopy combined with immunogold-labeling showed multiple small 53BP1 clusters diffusely distributed throughout the highly compacted heterochromatin of aged HFSCs, but single large 53BP1 clusters in irradiated HFSCs. These remaining 53BP1 clusters did not colocalize with core components of non-homologous end-joining, but with heterochromatic histone modifications. Based on these results we hypothesize that these lesions were not persistently unrepaired DSBs, but may reflect chromatin rearrangements caused by the repair or misrepair of DSBs. Flow cytometry showed increased activation of repair proteins and damage-induced chromatin modifications, triggering apoptosis and cellular senescence in irradiated, but not in aged HFSCs. These results suggest that accumulation of DNA damage-induced chromatin alterations, whose structural dimensions reflect the complexity of the initial genotoxic insult, may lead to different DDR events, ultimately determining the biological outcome of HFSCs. Collectively, our findings support the hypothesis that aging might be largely the remit of structural changes to chromatin potentially leading to epigenetically induced transcriptional deregulation.
Collapse
|
36
|
González-Marín C, Gosálvez J, Roy R. Types, causes, detection and repair of DNA fragmentation in animal and human sperm cells. Int J Mol Sci 2012; 13:14026-52. [PMID: 23203048 PMCID: PMC3509564 DOI: 10.3390/ijms131114026] [Citation(s) in RCA: 198] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2012] [Revised: 10/16/2012] [Accepted: 10/18/2012] [Indexed: 01/09/2023] Open
Abstract
Concentration, motility and morphology are parameters commonly used to determine the fertilization potential of an ejaculate. These parameters give a general view on the quality of sperm but do not provide information about one of the most important components of the reproductive outcome: DNA. Either single or double DNA strand breaks can set the difference between fertile and infertile males. Sperm DNA fragmentation can be caused by intrinsic factors like abortive apoptosis, deficiencies in recombination, protamine imbalances or oxidative stress. Damage can also occur due to extrinsic factors such as storage temperatures, extenders, handling conditions, time after ejaculation, infections and reaction to medicines or post-testicular oxidative stress, among others. Two singular characteristics differentiate sperm from somatic cells: Protamination and absence of DNA repair. DNA repair in sperm is terminated as transcription and translation stops post-spermiogenesis, so these cells have no mechanism to repair the damage occurred during their transit through the epididymis and post-ejaculation. Oocytes and early embryos have been shown to repair sperm DNA damage, so the effect of sperm DNA fragmentation depends on the combined effects of sperm chromatin damage and the capacity of the oocyte to repair it. In this contribution we review some of these issues.
Collapse
Affiliation(s)
- Clara González-Marín
- Sexing Technologies, 22575 State Highway 6 South, Navasota, TX 77868, USA; E-Mail:
| | - Jaime Gosálvez
- Biology Department, Universidad Autonoma of Madrid, C/ Darwin nº 2. 28049 Madrid, Spain; E-Mail:
| | - Rosa Roy
- Biology Department, Universidad Autonoma of Madrid, C/ Darwin nº 2. 28049 Madrid, Spain; E-Mail:
| |
Collapse
|
37
|
Schanz S, Schuler N, Lorat Y, Fan L, Kaestner L, Wennemuth G, Rübe C, Rübe CE. Accumulation of DNA damage in complex normal tissues after protracted low-dose radiation. DNA Repair (Amst) 2012; 11:823-32. [PMID: 22947398 DOI: 10.1016/j.dnarep.2012.07.005] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2012] [Revised: 07/12/2012] [Accepted: 07/19/2012] [Indexed: 01/08/2023]
Abstract
The biological consequences of low levels of radiation exposure and their effects on human health are unclear. Ionizing radiation induces a variety of lesions of which DNA double-strand breaks (DSBs) are the most biologically significant, because unrepaired or misrepaired DSBs can lead to genomic instability and cell death. Using repair-proficient mice as an in vivo system we monitored the accumulation of DNA damage in normal tissues exposed to daily low-dose radiation of 100mGy or 10mGy. Radiation-induced foci in differentiated and tissue-specific stem cells were quantified by immunofluorescence microscopy after 2, 4, 6, 8, and 10 weeks of daily low-dose radiation and DNA lesions were characterized using transmission electron microscopy (TEM) combined with immunogold-labeling. In brain, long-living cortical neurons had a significant accumulation of foci with increasing cumulative doses. In intestine and skin, characterized by constant cell renewal of their epithelial lining, differentiated enterocytes and keratinocytes had either unchanged or only slightly increased foci levels during protracted low-dose radiation. Significantly, analysis of epidermal stem cells in skin revealed a constant increase of 53BP1 foci during the first weeks of low-dose radiation even with 10mGy, suggesting substantial accumulations of DSBs. However, TEM analysis suggests that these remaining 53BP1 foci, which are predominantly located in compact heterochromatin, do not co-localize with phosphorylated Ku70 or DNA-PKcs, core components of non-homologous end-joining. The biological relevance of these persistent 53BP1 foci, particularly their contribution to genomic instability by genetic and epigenetic alterations, has to be defined in future studies.
Collapse
Affiliation(s)
- Stefanie Schanz
- Department of Radiation Oncology, Saarland University, Homburg, Saar, Germany
| | | | | | | | | | | | | | | |
Collapse
|
38
|
Cordelli E, Eleuteri P, Grollino MG, Benassi B, Blandino G, Bartoleschi C, Pardini MC, Di Caprio EV, Spanò M, Pacchierotti F, Villani P. Direct and delayed X-ray-induced DNA damage in male mouse germ cells. ENVIRONMENTAL AND MOLECULAR MUTAGENESIS 2012; 53:429-439. [PMID: 22730201 DOI: 10.1002/em.21703] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2011] [Revised: 04/18/2012] [Accepted: 04/19/2012] [Indexed: 06/01/2023]
Abstract
Sperm DNA integrity is essential for the accurate transmission of paternal genetic information. Various stages of spermatogenesis are characterized by large differences in radiosensitivity. Differentiating spermatogonia are susceptible to radiation-induced cell killing, but some of them can repair DNA damage and progress through differentiation. In this study, we applied the neutral comet assay, immunodetection of phosphorylated H2AX (γ-H2AX) and the Sperm Chromatin Structure Assay (SCSA) to detect DNA strand breaks in testicular cells and spermatozoa at different times following in vivo X-ray irradiation. Radiation produced DNA strand breaks in testicular cells that were repaired within the first few hours after exposure. Spermatozoa were resistant to the induction of DNA damage, but non-targeted DNA lesions were detected in spermatozoa derived from surviving irradiated spermatogonia. These lesions formed while round spermatids started to elongate within the testicular seminiferous tubules. The transcription of pro-apoptotic genes at this time was also enhanced, suggesting that an apoptotic-like process was involved in DNA break production. Our results suggest that proliferating spermatogonia retain a memory of the radiation insult that is recognized at a later developmental stage and activates a process leading to DNA fragmentation.
Collapse
|
39
|
Guan K, Cheng IF, Baazm M. Human spermatagonial stem cells: a novel therapeutic hope for cardiac regeneration and repair? Future Cardiol 2012; 8:39-51. [DOI: 10.2217/fca.11.78] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Although the identification and characterization of human spermatogonial stem cells was reported nearly 50 years ago, great progress has been made only in the last few years. Spermatogonial stem cells attract a great deal of researchers’ attention because of their unique characteristics, including the ability to be converted spontaneously into pluripotent germline stem cells with embryonic stem cell-like properties. Pluripotent stem cells are able to differentiate into any desired cell type in the body; therefore, they are the most promising cell source for organ regeneration. The advantages of pluripotent germline stem cells over other stem cells are that they maintain a high degree of DNA integrity and can resolve some ethical and immunological problems related to human embryonic stem cells. In this article we address the origin, characteristics and pluripotency of spermatogonial stem cells. Their contribution to stem cell-based organ regeneration therapy with special emphasis on cardiac regeneration and repair in the future is also discussed.
Collapse
Affiliation(s)
| | - I-Fen Cheng
- Department of Cardiology & Pneumology, Robert-Koch-Str. 40, Georg-August-University Göttingen, 37075 Göttingen, Germany
| | - Maryam Baazm
- Department of Cardiology & Pneumology, Robert-Koch-Str. 40, Georg-August-University Göttingen, 37075 Göttingen, Germany
- Department of Anatomical Sciences, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran
| |
Collapse
|
40
|
H2AX phosphorylation at the sites of DNA double-strand breaks in cultivated mammalian cells and tissues. Clin Epigenetics 2011; 2:283-97. [PMID: 22704343 PMCID: PMC3365398 DOI: 10.1007/s13148-011-0044-4] [Citation(s) in RCA: 88] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2011] [Accepted: 06/10/2011] [Indexed: 11/24/2022] Open
Abstract
A sequence variant of histone H2A called H2AX is one of the key components of chromatin involved in DNA damage response induced by different genotoxic stresses. Phosphorylated H2AX (γH2AX) is rapidly concentrated in chromatin domains around DNA double-strand breaks (DSBs) after the action of ionizing radiation or chemical agents and at stalled replication forks during replication stress. γH2AX foci could be easily detected in cell nuclei using immunofluorescence microscopy that allows to use γH2AX as a quantitative marker of DSBs in various applications. H2AX is phosphorylated in situ by ATM, ATR, and DNA-PK kinases that have distinct roles in different pathways of DSB repair. The γH2AX serves as a docking site for the accumulation of DNA repair proteins, and after rejoining of DSBs, it is released from chromatin. The molecular mechanism of γH2AX dephosphorylation is not clear. It is complicated and requires the activity of different proteins including phosphatases and chromatin-remodeling complexes. In this review, we summarize recently published data concerning the mechanisms and kinetics of γH2AX loss in normal cells and tissues as well as in those deficient in ATM, DNA-PK, and DSB repair proteins activity. The results of the latest scientific research of the low-dose irradiation phenomenon are presented including the bystander effect and the adaptive response estimated by γH2AX detection in cells and tissues.
Collapse
|
41
|
Rübe CE, Fricke A, Widmann TA, Fürst T, Madry H, Pfreundschuh M, Rübe C. Accumulation of DNA damage in hematopoietic stem and progenitor cells during human aging. PLoS One 2011; 6:e17487. [PMID: 21408175 PMCID: PMC3049780 DOI: 10.1371/journal.pone.0017487] [Citation(s) in RCA: 236] [Impact Index Per Article: 18.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2010] [Accepted: 02/05/2011] [Indexed: 12/15/2022] Open
Abstract
Background Accumulation of DNA damage leading to adult stem cell exhaustion has been proposed to be a principal mechanism of aging. Here we tested this hypothesis in healthy individuals of different ages by examining unrepaired DNA double-strand breaks (DSBs) in hematopoietic stem/progenitor cells matured in their physiological microenvironment. Methodology/Principal Findings To asses DNA damage accumulation and repair capacities, γH2AX-foci were examined before and after exposure to ionizing irradiation. Analyzing CD34+ and CD34− stem/progenitor cells we observed an increase of endogenous γH2AX-foci levels with advancing donor age, associated with an age-related decline in telomere length. Using combined immunofluorescence and telomere-fluorescence in-situ hybridization we show that γH2AX-foci co-localize consistently with other repair factors such as pATM, MDC1 and 53BP1, but not significantly with telomeres, strongly supporting the telomere-independent origin for the majority of foci. The highest inter-individual variations for non-telomeric DNA damage were observed in middle-aged donors, whereas the individual DSB repair capacity appears to determine the extent of DNA damage accrual. However, analyzing different stem/progenitor subpopulations obtained from healthy elderly (>70 years), we observed an only modest increase in DNA damage accrual, most pronounced in the primitive CD34+CD38−-enriched subfraction, but sustained DNA repair efficiencies, suggesting that healthy lifestyle may slow down the natural aging process. Conclusions/Significance Based on these findings we conclude that age-related non-telomeric DNA damage accrual accompanies physiological stem cell aging in humans. Moreover, aging may alter the functional capacity of human stem cells to repair DSBs, thereby deteriorating an important genome protection mechanism leading to exceeding DNA damage accumulation. However, the great inter-individual variations in middle-aged individuals suggest that additional cell-intrinsic mechanisms and/or extrinsic factors contribute to the age-associated DNA damage accumulation.
Collapse
Affiliation(s)
- Claudia E Rübe
- Department of Radiation Oncology, Saarland University, Homburg/Saar, Germany.
| | | | | | | | | | | | | |
Collapse
|