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Abdallah S, Jampy A, Moison D, Wieckowski M, Messiaen S, Martini E, Campalans A, Radicella JP, Rouiller-Fabre V, Livera G, Guerquin MJ. Foetal exposure to the bisphenols BADGE and BPAF impairs meiosis through DNA oxidation in mouse ovaries. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2023; 317:120791. [PMID: 36464114 DOI: 10.1016/j.envpol.2022.120791] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/06/2022] [Revised: 11/16/2022] [Accepted: 11/28/2022] [Indexed: 06/17/2023]
Abstract
Many endocrine disruptors have been proven to impair the meiotic process which is required for the production of healthy gametes. Bisphenol A is emblematic of such disruptors, as it impairs meiotic prophase I and causes oocyte aneuploidy following in utero exposure. However, the mechanisms underlying these deleterious effects remain poorly understood. Furthermore, the increasing use of BPA alternatives raises concerns for public health. Here, we investigated the effects of foetal exposure to two BPA alternatives, bisphenol A Diglycidyl Ether (BADGE) and bisphenol AF (BPAF), on oogenesis in mice. These compounds delay meiosis initiation, increase the number of MLH1 foci per cell and induce oocyte aneuploidy. We further demonstrate that these defects are accompanied by changes in gene expression in foetal premeiotic germ cells and aberrant mRNA splicing of meiotic genes. We observed an increase in DNA oxidation after exposure to BPA alternatives. Specific induction of oxidative DNA damage during foetal germ cell differentiation causes similar defects during oogenesis, as observed in 8-oxoguanine DNA Glycosylase (OGG1)-deficient mice or after in utero exposure to potassium bromate (KBrO3), an inducer of oxidative DNA damage. The supplementation of BPA alternatives with N-acetylcysteine (NAC) counteracts the effects of bisphenols on meiosis. Together, our results propose oxidative DNA lesion as an event that negatively impacts female meiosis with major consequences on oocyte quality. This could be a common mechanism of action for numerous environmental pro-oxidant pollutants, and its discovery, could lead to reconsider the adverse effect of bisphenol mixtures that are simultaneously present in our environment.
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Affiliation(s)
- Sonia Abdallah
- Université Paris-Saclay, CEA, Stabilité Génétique Cellules Souches et Radiations, Institut de Biologie François Jacob, 92260, Fontenay aux Roses, France; Université de Paris-Cité, CEA, Stabilité Génétique Cellules Souches et Radiations, Institut de Biologie François Jacob, 92260, Fontenay aux Roses, France; Laboratory of the Development of the Gonads, France
| | - Amandine Jampy
- Université Paris-Saclay, CEA, Stabilité Génétique Cellules Souches et Radiations, Institut de Biologie François Jacob, 92260, Fontenay aux Roses, France; Université de Paris-Cité, CEA, Stabilité Génétique Cellules Souches et Radiations, Institut de Biologie François Jacob, 92260, Fontenay aux Roses, France; Laboratory of the Development of the Gonads, France
| | - Delphine Moison
- Université Paris-Saclay, CEA, Stabilité Génétique Cellules Souches et Radiations, Institut de Biologie François Jacob, 92260, Fontenay aux Roses, France; Université de Paris-Cité, CEA, Stabilité Génétique Cellules Souches et Radiations, Institut de Biologie François Jacob, 92260, Fontenay aux Roses, France; Laboratory of the Development of the Gonads, France
| | - Margaux Wieckowski
- Université Paris-Saclay, CEA, Stabilité Génétique Cellules Souches et Radiations, Institut de Biologie François Jacob, 92260, Fontenay aux Roses, France; Université de Paris-Cité, CEA, Stabilité Génétique Cellules Souches et Radiations, Institut de Biologie François Jacob, 92260, Fontenay aux Roses, France; Laboratory of the Development of the Gonads, France
| | - Sébastien Messiaen
- Université Paris-Saclay, CEA, Stabilité Génétique Cellules Souches et Radiations, Institut de Biologie François Jacob, 92260, Fontenay aux Roses, France; Université de Paris-Cité, CEA, Stabilité Génétique Cellules Souches et Radiations, Institut de Biologie François Jacob, 92260, Fontenay aux Roses, France; Laboratory of the Development of the Gonads, France
| | - Emmanuelle Martini
- Université Paris-Saclay, CEA, Stabilité Génétique Cellules Souches et Radiations, Institut de Biologie François Jacob, 92260, Fontenay aux Roses, France; Université de Paris-Cité, CEA, Stabilité Génétique Cellules Souches et Radiations, Institut de Biologie François Jacob, 92260, Fontenay aux Roses, France; Laboratory of the Development of the Gonads, France
| | - Anna Campalans
- Université Paris-Saclay, CEA, Stabilité Génétique Cellules Souches et Radiations, Institut de Biologie François Jacob, 92260, Fontenay aux Roses, France; Université de Paris-Cité, CEA, Stabilité Génétique Cellules Souches et Radiations, Institut de Biologie François Jacob, 92260, Fontenay aux Roses, France
| | - Juan Pablo Radicella
- Université Paris-Saclay, CEA, Stabilité Génétique Cellules Souches et Radiations, Institut de Biologie François Jacob, 92260, Fontenay aux Roses, France; Université de Paris-Cité, CEA, Stabilité Génétique Cellules Souches et Radiations, Institut de Biologie François Jacob, 92260, Fontenay aux Roses, France
| | - Virginie Rouiller-Fabre
- Université Paris-Saclay, CEA, Stabilité Génétique Cellules Souches et Radiations, Institut de Biologie François Jacob, 92260, Fontenay aux Roses, France; Université de Paris-Cité, CEA, Stabilité Génétique Cellules Souches et Radiations, Institut de Biologie François Jacob, 92260, Fontenay aux Roses, France; Laboratory of the Development of the Gonads, France
| | - Gabriel Livera
- Université Paris-Saclay, CEA, Stabilité Génétique Cellules Souches et Radiations, Institut de Biologie François Jacob, 92260, Fontenay aux Roses, France; Université de Paris-Cité, CEA, Stabilité Génétique Cellules Souches et Radiations, Institut de Biologie François Jacob, 92260, Fontenay aux Roses, France; Laboratory of the Development of the Gonads, France
| | - Marie-Justine Guerquin
- Université Paris-Saclay, CEA, Stabilité Génétique Cellules Souches et Radiations, Institut de Biologie François Jacob, 92260, Fontenay aux Roses, France; Université de Paris-Cité, CEA, Stabilité Génétique Cellules Souches et Radiations, Institut de Biologie François Jacob, 92260, Fontenay aux Roses, France; Laboratory of the Development of the Gonads, France.
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Arkoun B, Moison P, Guerquin MJ, Messiaen S, Moison D, Tourpin S, Monville C, Livera G. Sorting and Manipulation of Human PGC-LC Using PDPN and Hanging Drop Cultures. Cells 2022; 11:cells11233832. [PMID: 36497094 PMCID: PMC9736549 DOI: 10.3390/cells11233832] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2022] [Revised: 11/22/2022] [Accepted: 11/25/2022] [Indexed: 12/05/2022] Open
Abstract
The generation of oocytes from induced pluripotent stem cells (iPSCs) was proven efficient with mouse cells. However, no human iPSCs have yet been reported to generate cells able to complete oogenesis. Additionally, efficient sorting of human Primordial Germ Cell-like Cells (hPGC-LCs) without genomic integration of fluorescent reporter for their downstream manipulation is still lacking. Here, we aimed to develop a model that allows human germ cell differentiation in vitro in order to study the developing human germline. The hPGC-LCs specified from two iPS cell lines were sorted and manipulated using the PDPN surface marker without genetic modification. hPGC-LCs obtained remain arrested at early stages of maturation and no further differentiation nor meiotic onset occurred when these were cultured with human or mouse fetal ovarian somatic cells. However, when cultured independently of somatic ovarian cells, using BMP4 and the hanging drop-transferred EBs system, early hPGC-LCs further differentiate efficiently and express late PGC (DDX4) and meiotic gene markers, although no SYCP3 protein was detected. Altogether, we characterized a tool to sort hPGC-LCs and an efficient in vitro differentiation system to obtain pre-meiotic germ cell-like cells without using a gonadal niche.
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Affiliation(s)
- Brahim Arkoun
- Laboratoire de Développement des Gonades, UMRE008 Stabilité Génétique Cellules Souches et Radiations, Université Paris Cité, Université Paris-Saclay, CEA, 92265 Fontenay-aux-Roses, France
| | - Pauline Moison
- Laboratoire de Développement des Gonades, UMRE008 Stabilité Génétique Cellules Souches et Radiations, Université Paris Cité, Université Paris-Saclay, CEA, 92265 Fontenay-aux-Roses, France
| | - Marie-Justine Guerquin
- Laboratoire de Développement des Gonades, UMRE008 Stabilité Génétique Cellules Souches et Radiations, Université Paris Cité, Université Paris-Saclay, CEA, 92265 Fontenay-aux-Roses, France
| | - Sébastien Messiaen
- Laboratoire de Développement des Gonades, UMRE008 Stabilité Génétique Cellules Souches et Radiations, Université Paris Cité, Université Paris-Saclay, CEA, 92265 Fontenay-aux-Roses, France
| | - Delphine Moison
- Laboratoire de Développement des Gonades, UMRE008 Stabilité Génétique Cellules Souches et Radiations, Université Paris Cité, Université Paris-Saclay, CEA, 92265 Fontenay-aux-Roses, France
| | - Sophie Tourpin
- Laboratoire de Développement des Gonades, UMRE008 Stabilité Génétique Cellules Souches et Radiations, Université Paris Cité, Université Paris-Saclay, CEA, 92265 Fontenay-aux-Roses, France
| | - Christelle Monville
- INSERM U861, I-Stem, AFM, Institute for Stem Cell Therapy and Exploration of Monogenic Diseases, 91100 Corbeil-Essonnes, France
- Paris-Saclay Evry, U861, 91100 Corbeil-Essonnes, France
| | - Gabriel Livera
- Laboratoire de Développement des Gonades, UMRE008 Stabilité Génétique Cellules Souches et Radiations, Université Paris Cité, Université Paris-Saclay, CEA, 92265 Fontenay-aux-Roses, France
- Correspondence: ; Tel.: +33-(0)1-46-54-99-12
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Divergent Roles of CYP26B1 and Endogenous Retinoic Acid in Mouse Fetal Gonads. Biomolecules 2019; 9:biom9100536. [PMID: 31561560 PMCID: PMC6843241 DOI: 10.3390/biom9100536] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2019] [Revised: 09/17/2019] [Accepted: 09/24/2019] [Indexed: 11/19/2022] Open
Abstract
In female mammals, germ cells enter meiosis in the fetal ovaries, while in males, meiosis is prevented until postnatal development. Retinoic acid (RA) is considered the main inducer of meiotic entry, as it stimulates Stra8 which is required for the mitotic/meiotic switch. In fetal testes, the RA-degrading enzyme CYP26B1 prevents meiosis initiation. However, the role of endogenous RA in female meiosis entry has never been demonstrated in vivo. In this study, we demonstrate that some effects of RA in mouse fetal gonads are not recapitulated by the invalidation or up-regulation of CYP26B1. In organ culture of fetal testes, RA stimulates testosterone production and inhibits Sertoli cell proliferation. In the ovaries, short-term inhibition of RA-signaling does not decrease Stra8 expression. We develop a gain-of-function model to express CYP26A1 or CYP26B1. Only CYP26B1 fully prevents STRA8 induction in female germ cells, confirming its role as part of the meiotic prevention machinery. CYP26A1, a very potent RA degrading enzyme, does not impair the formation of STRA8-positive cells, but decreases Stra8 transcription. Collectively, our data reveal that CYP26B1 has other activities apart from metabolizing RA in fetal gonads and suggest a role of endogenous RA in amplifying Stra8, rather than being the initial inducer of Stra8. These findings should reactivate the quest to identify meiotic preventing or inducing substances.
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DiTroia SP, Percharde M, Guerquin MJ, Wall E, Collignon E, Ebata KT, Mesh K, Mahesula S, Agathocleous M, Laird DJ, Livera G, Ramalho-Santos M. Maternal vitamin C regulates reprogramming of DNA methylation and germline development. Nature 2019; 573:271-275. [PMID: 31485074 PMCID: PMC8423347 DOI: 10.1038/s41586-019-1536-1] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2018] [Accepted: 08/02/2019] [Indexed: 02/07/2023]
Abstract
Development is often assumed to be hardwired in the genome, but several lines of evidence indicate that it is susceptible to environmental modulation with potential long-term consequences, including in mammals1,2. The embryonic germline is of particular interest because of the potential for intergenerational epigenetic effects. The mammalian germline undergoes extensive DNA demethylation3-7 that occurs in large part by passive dilution of methylation over successive cell divisions, accompanied by active DNA demethylation by TET enzymes3,8-10. TET activity has been shown to be modulated by nutrients and metabolites, such as vitamin C11-15. Here we show that maternal vitamin C is required for proper DNA demethylation and the development of female fetal germ cells in a mouse model. Maternal vitamin C deficiency does not affect overall embryonic development but leads to reduced numbers of germ cells, delayed meiosis and reduced fecundity in adult offspring. The transcriptome of germ cells from vitamin-C-deficient embryos is remarkably similar to that of embryos carrying a null mutation in Tet1. Vitamin C deficiency leads to an aberrant DNA methylation profile that includes incomplete demethylation of key regulators of meiosis and transposable elements. These findings reveal that deficiency in vitamin C during gestation partially recapitulates loss of TET1, and provide a potential intergenerational mechanism for adjusting fecundity to environmental conditions.
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Affiliation(s)
- Stephanie P DiTroia
- Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research, University of California, San Francisco, San Francisco, CA, USA
- Center for Reproductive Sciences, University of California, San Francisco, San Francisco, CA, USA
- Medical and Population Genetics, Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Michelle Percharde
- Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research, University of California, San Francisco, San Francisco, CA, USA
- Center for Reproductive Sciences, University of California, San Francisco, San Francisco, CA, USA
- MRC London Institute of Medical Sciences (LMS), London, UK
- Institute of Clinical Sciences (ICS), Faculty of Medicine, Imperial College London, London, UK
| | - Marie-Justine Guerquin
- UMR967 INSERM, CEA/DRF/iRCM/SCSR/LDG, Université Paris Diderot, Sorbonne Paris Cité, Université Paris-Sud, Université Paris-Saclay, Laboratory of Development of the Gonads, Fontenay aux Roses, France
| | - Estelle Wall
- Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research, University of California, San Francisco, San Francisco, CA, USA
- Center for Reproductive Sciences, University of California, San Francisco, San Francisco, CA, USA
| | - Evelyne Collignon
- Lunenfeld-Tanenbaum Research Institute and Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
| | - Kevin T Ebata
- Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research, University of California, San Francisco, San Francisco, CA, USA
- Center for Reproductive Sciences, University of California, San Francisco, San Francisco, CA, USA
| | - Kathryn Mesh
- Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research, University of California, San Francisco, San Francisco, CA, USA
- Center for Reproductive Sciences, University of California, San Francisco, San Francisco, CA, USA
| | - Swetha Mahesula
- Children's Research Institute and the Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Michalis Agathocleous
- Children's Research Institute and the Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Diana J Laird
- Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research, University of California, San Francisco, San Francisco, CA, USA
- Center for Reproductive Sciences, University of California, San Francisco, San Francisco, CA, USA
| | - Gabriel Livera
- UMR967 INSERM, CEA/DRF/iRCM/SCSR/LDG, Université Paris Diderot, Sorbonne Paris Cité, Université Paris-Sud, Université Paris-Saclay, Laboratory of Development of the Gonads, Fontenay aux Roses, France
| | - Miguel Ramalho-Santos
- Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research, University of California, San Francisco, San Francisco, CA, USA.
- Center for Reproductive Sciences, University of California, San Francisco, San Francisco, CA, USA.
- Lunenfeld-Tanenbaum Research Institute and Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada.
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Abstract
Germ cells are the stem cells of the species. Thus, it is critical that we have a good understanding of how they are specified, how the somatic cells instruct and support them, how they commit to one or other sex, and how they ultimately develop into functional gametes. Here, we focus on specifics of how sexual fate is determined during fetal life. Because the majority of relevant experimental work has been done using the mouse model, we focus on that species. We review evidence regarding the identity of instructive signals from the somatic cells, and the molecular responses that occur in germ cells in response to those extrinsic signals. In this way we aim to clarify progress to date regarding the mechanisms underlying the mitotic to meiosis switch in germ cells of the fetal ovary, and those involved in adopting and securing male fate in germ cells of the fetal testis.
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Affiliation(s)
- Cassy Spiller
- School of Biomedical Sciences, The University of Queensland, Brisbane, QLD, Australia
| | - Josephine Bowles
- School of Biomedical Sciences, The University of Queensland, Brisbane, QLD, Australia; Institute for Molecular Bioscience, The University of Queensland, Brisbane, QLD, Australia.
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Mu X, Wen J, Chen Q, Wang Z, Wang Y, Guo M, Yang Y, Xu J, Wei Z, Xia G, Yang M, Wang C. Retinoic acid-induced CYP51 nuclear translocation promotes meiosis prophase I process and is correlated to the expression of REC8 and STAG3 in mice. Biol Open 2018; 7:bio.035626. [PMID: 30420384 PMCID: PMC6262859 DOI: 10.1242/bio.035626] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Lanosterol 14 α-demethylase (CYP51) plays a crucial role in cholesterol biosynthesis. In gamete development, CYP51 is involved in initiating meiosis resumption in oocytes through its product, meiosis activating sterol (MAS). In this study, CYP51 was observed to localize within the nucleus of germ cells undergoing meiotic prophase I. Following the addition of retinoic acid (RA) to induce meiosis or the RA receptor pan-antagonist AGN193109 to block meiosis in fetal ovaries, the translocation of CYP51 into the nucleus of oocytes was advanced or delayed, respectively. In addition, treatment with Cyp51-siRNA or RS21745, a specific CYP51 inhibitor, significantly delayed the meiotic progression of oocytes in the ovary, with most oocytes arresting at the zygotene stage, and likewise, significantly reduced perinatal primordial follicle formation. Furthermore, inhibition of CYP51 is correlated to significantly decreased expression of REC8 and STAG3, both of which are meiosis-specific cohesin subunits. To sum up, RA-induced CYP51 nuclear translocation is critical for oocytes meiotic progression, and consequently folliculogenesis, which might act through impacting the expression of meiosis-specific cohesins REC8 and STAG3. Summary: CYP51 displays cytoplasm-to-nucleus translocation in germ cells in mice. CYP51 participates in germ cell meiotic progression and folliculogenesis via regulating the expression of cohesin REC8 and STAG3.
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Affiliation(s)
- Xinyi Mu
- State Key Laboratory of Agrobiotechnology, College of Biological Sciences, China Agricultural University, Beijing 100193, China.,Department of Histology and Embryology, Chongqing Medical University, Chongqing 400016, China
| | - Jia Wen
- State Key Laboratory of Agrobiotechnology, College of Biological Sciences, China Agricultural University, Beijing 100193, China
| | - Qian Chen
- State Key Laboratory of Agrobiotechnology, College of Biological Sciences, China Agricultural University, Beijing 100193, China
| | - Zhengpin Wang
- State Key Laboratory of Agrobiotechnology, College of Biological Sciences, China Agricultural University, Beijing 100193, China
| | - Yijing Wang
- State Key Laboratory of Agrobiotechnology, College of Biological Sciences, China Agricultural University, Beijing 100193, China
| | - Meng Guo
- Department of Laboratory Animal Science, School of Basic Medical Science, Capital Medical University, Beijing 100069, China
| | - Yi Yang
- Key Laboratory of Ministry of Education for Conservation and Utilization of Special Biological Resources in the Western China, College of Life Science, Ningxia University, 539 W Helanshan Road, Xixia District, Yinchuan, Ningxia 750021, China
| | - JinRui Xu
- Key Laboratory of Ministry of Education for Conservation and Utilization of Special Biological Resources in the Western China, College of Life Science, Ningxia University, 539 W Helanshan Road, Xixia District, Yinchuan, Ningxia 750021, China
| | - Zhiqing Wei
- Key Laboratory of Ministry of Education for Conservation and Utilization of Special Biological Resources in the Western China, College of Life Science, Ningxia University, 539 W Helanshan Road, Xixia District, Yinchuan, Ningxia 750021, China
| | - Guoliang Xia
- State Key Laboratory of Agrobiotechnology, College of Biological Sciences, China Agricultural University, Beijing 100193, China.,Key Laboratory of Ministry of Education for Conservation and Utilization of Special Biological Resources in the Western China, College of Life Science, Ningxia University, 539 W Helanshan Road, Xixia District, Yinchuan, Ningxia 750021, China
| | - Mengye Yang
- Department of Biochemistry, College of Life Sciences, Wuhan University, Luojia Hill, Wuhan 430072, China
| | - Chao Wang
- State Key Laboratory of Agrobiotechnology, College of Biological Sciences, China Agricultural University, Beijing 100193, China
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Frydman N, Poulain M, Arkoun B, Duquenne C, Tourpin S, Messiaen S, Habert R, Rouiller-Fabre V, Benachi A, Livera G. Human foetal ovary shares meiotic preventing factors with the developing testis. Hum Reprod 2018; 32:631-642. [PMID: 28073973 DOI: 10.1093/humrep/dew343] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2015] [Accepted: 12/14/2016] [Indexed: 12/13/2022] Open
Abstract
STUDY QUESTION How can pre-meiotic germ cells persist in the human foetal ovary? SUMMARY ANSWER Numerous oogonia escaping meiotic entry were retrieved throughout human ovarian development simultaneously with the expression of signalling pathways preventing meiosis, typically described in the rodent embryonic testis. WHAT IS KNOWN ALREADY The transition from mitosis to meiosis is a key event in female germ cells that remains poorly documented in research on the human ovary. Previous reports described a strikingly asynchronous differentiation in the human female germ line during development, with the persistence of oogonia among oocytes and follicles during the second and third trimesters. The possible mechanisms allowing some cells to escape meiosis remain elusive. STUDY DESIGN SIZE, DURATION In order to document the extent of this phenomenon, we detailed the expression profile of germ cell differentiation markers using 73 ovaries ranging from 6.4 to 35 weeks post-fertilization. PARTICIPANTS/MATERIALS SETTING, METHODS Pre-meiotic markers were detected by immunohistochemistry or qRT-PCR. The expression of the main meiosis-preventing factors identified in mice was analysed, and their functionality assessed using organ cultures. MAIN RESULTS AND THE ROLE OF CHANCE Oogonia stained for AP2γ could be traced from the first trimester until the end of the third trimester. Female germ cell differentiation is organized both in time and space in a centripetal manner in the foetal human ovary. Unexpectedly, some features usually ascribed to rodent pre-spermatogonia could be observed in human foetal ovaries, such as NANOS2 expression and quiescence in some germ cells. The two main somatic signals known to inhibit meiosis in the mouse embryonic testis, CYP26B1 and FGF9, were detected in the human ovary and act simultaneously to repress STRA8 and meiosis in human foetal female germ cells. LARGE SCALE DATA N/A. LIMITATIONS REASON FOR CAUTION Our conclusions relied partly on in vitro experiments. Germ cells were not systematically identified with immunostaining and some may have thus escaped analysis. WIDER IMPLICATIONS OF THE FINDINGS We found evidence that a robust repression of meiotic entry is taking place in the human foetal ovary, possibly explaining the exceptional long-lasting presence of pre-meiotic germ cells until late gestational age. This result calls for a redefinition of the markers known as classical male markers, which may in fact characterize mammalian developing gonads irrespectively of their sex. STUDY FUNDING/COMPETING INTEREST(S) This research was supported by the Université Paris Diderot-Paris 7 and Université Paris-Sud, CEA, INSERM, and Agence de la Biomédecine. The authors declare no conflict of interest.
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Affiliation(s)
- Nelly Frydman
- Laboratory of Development of the Gonads, Unit of Genetic Stability, Stem Cells and Radiation, UMR 967, INSERM, CEA/DSV/iRCM/SCSR, Univ. Paris Diderot, Sorbonne Paris Cité, Univ. Paris-Sud, Université Paris-Saclay, Fontenay aux Roses F-92265, France.,AP-HP, Reproductive Biology Unit, Univ. Paris-Sud, Université Paris-Saclay, Hôpital Antoine Béclère, Clamart F-92140, France
| | - Marine Poulain
- Laboratory of Development of the Gonads, Unit of Genetic Stability, Stem Cells and Radiation, UMR 967, INSERM, CEA/DSV/iRCM/SCSR, Univ. Paris Diderot, Sorbonne Paris Cité, Univ. Paris-Sud, Université Paris-Saclay, Fontenay aux RosesF-92265, France
| | - Brahim Arkoun
- Laboratory of Development of the Gonads, Unit of Genetic Stability, Stem Cells and Radiation, UMR 967, INSERM, CEA/DSV/iRCM/SCSR, Univ. Paris Diderot, Sorbonne Paris Cité, Univ. Paris-Sud, Université Paris-Saclay, Fontenay aux RosesF-92265, France
| | - Clotilde Duquenne
- Laboratory of Development of the Gonads, Unit of Genetic Stability, Stem Cells and Radiation, UMR 967, INSERM, CEA/DSV/iRCM/SCSR, Univ. Paris Diderot, Sorbonne Paris Cité, Univ. Paris-Sud, Université Paris-Saclay, Fontenay aux RosesF-92265, France
| | - Sophie Tourpin
- Laboratory of Development of the Gonads, Unit of Genetic Stability, Stem Cells and Radiation, UMR 967, INSERM, CEA/DSV/iRCM/SCSR, Univ. Paris Diderot, Sorbonne Paris Cité, Univ. Paris-Sud, Université Paris-Saclay, Fontenay aux RosesF-92265, France
| | - Sébastien Messiaen
- Laboratory of Development of the Gonads, Unit of Genetic Stability, Stem Cells and Radiation, UMR 967, INSERM, CEA/DSV/iRCM/SCSR, Univ. Paris Diderot, Sorbonne Paris Cité, Univ. Paris-Sud, Université Paris-Saclay, Fontenay aux RosesF-92265, France
| | - René Habert
- Laboratory of Development of the Gonads, Unit of Genetic Stability, Stem Cells and Radiation, UMR 967, INSERM, CEA/DSV/iRCM/SCSR, Univ. Paris Diderot, Sorbonne Paris Cité, Univ. Paris-Sud, Université Paris-Saclay, Fontenay aux RosesF-92265, France
| | - Virginie Rouiller-Fabre
- Laboratory of Development of the Gonads, Unit of Genetic Stability, Stem Cells and Radiation, UMR 967, INSERM, CEA/DSV/iRCM/SCSR, Univ. Paris Diderot, Sorbonne Paris Cité, Univ. Paris-Sud, Université Paris-Saclay, Fontenay aux RosesF-92265, France
| | - Alexandra Benachi
- AP-HP, Department of Obstetrics and Gynaecology, Univ. Paris-Sud, Université Paris-Saclay, Hôpital Antoine Béclère, ClamartF-92140, France
| | - Gabriel Livera
- Laboratory of Development of the Gonads, Unit of Genetic Stability, Stem Cells and Radiation, UMR 967, INSERM, CEA/DSV/iRCM/SCSR, Univ. Paris Diderot, Sorbonne Paris Cité, Univ. Paris-Sud, Université Paris-Saclay, Fontenay aux RosesF-92265, France
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8
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Shen C, Li M, Zhang P, Guo Y, Zhang H, Zheng B, Teng H, Zhou T, Guo X, Huo R. A Comparative Proteome Profile of Female Mouse Gonads Suggests a Tight Link between the Electron Transport Chain and Meiosis Initiation. Mol Cell Proteomics 2017; 17:31-42. [PMID: 29158290 DOI: 10.1074/mcp.m117.066993] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2017] [Revised: 08/24/2017] [Indexed: 01/23/2023] Open
Abstract
Generation of haploid gametes by meiosis is a unique property of germ cells and is critical for sexual reproduction. Leaving mitosis and entering meiosis is a key step in germ cell development. Several inducers or intrinsic genes are known to be important for meiotic initiation, but the regulation of meiotic initiation, especially at the protein level, is still not well understood. We constructed a comparative proteome profile of female mouse fetal gonads at specific time points (11.5, 12.5, and 13.5 days post coitum), spanning a critical window for initiation of meiosis in female germ cells. We identified 3666 proteins, of which 473 were differentially expressed. Further bioinformatics analysis showed that these differentially expressed proteins were enriched in the mitochondria, especially in the electron transport chain and, notably, 9 proteins in electron transport chain Complex I were differentially expressed. We disrupted the mitochondrial electron transport chain function by adding the complex I inhibitor, rotenone to 11.5 days post coitum female gonads cultured in vitro. This treatment resulted in a decreased proportion of meiotic germ cells, as assessed by staining for histone γH2AX. Rotenone treatment also caused decreased ATP levels, increased reactive oxygen species levels and failure of the germ cells to undergo premeiotic DNA replication. These effects were partially rescued by adding Coenzyme Q10. Taken together, our results suggested that a functional electron transport chain is important for meiosis initiation. Our characterization of the quantitative proteome of female gonads provides an inventory of proteins, useful for understanding the mechanisms of meiosis initiation and female fertility.
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Affiliation(s)
- Cong Shen
- From the ‡State Key Laboratory of Reproductive Medicine, Department of Histology and Embryology, Nanjing Medical University, Nanjing, 211166, P.R. China.,§Center for Reproduction and Genetics, Suzhou Municipal Hospital, Nanjing Medical University Affiliated Suzhou Hospital, Suzhou 215002, P.R. China
| | - Mingrui Li
- From the ‡State Key Laboratory of Reproductive Medicine, Department of Histology and Embryology, Nanjing Medical University, Nanjing, 211166, P.R. China
| | - Pan Zhang
- From the ‡State Key Laboratory of Reproductive Medicine, Department of Histology and Embryology, Nanjing Medical University, Nanjing, 211166, P.R. China
| | - Yueshuai Guo
- From the ‡State Key Laboratory of Reproductive Medicine, Department of Histology and Embryology, Nanjing Medical University, Nanjing, 211166, P.R. China
| | - Hao Zhang
- From the ‡State Key Laboratory of Reproductive Medicine, Department of Histology and Embryology, Nanjing Medical University, Nanjing, 211166, P.R. China
| | - Bo Zheng
- From the ‡State Key Laboratory of Reproductive Medicine, Department of Histology and Embryology, Nanjing Medical University, Nanjing, 211166, P.R. China.,§Center for Reproduction and Genetics, Suzhou Municipal Hospital, Nanjing Medical University Affiliated Suzhou Hospital, Suzhou 215002, P.R. China
| | - Hui Teng
- From the ‡State Key Laboratory of Reproductive Medicine, Department of Histology and Embryology, Nanjing Medical University, Nanjing, 211166, P.R. China
| | - Tao Zhou
- From the ‡State Key Laboratory of Reproductive Medicine, Department of Histology and Embryology, Nanjing Medical University, Nanjing, 211166, P.R. China
| | - Xuejiang Guo
- From the ‡State Key Laboratory of Reproductive Medicine, Department of Histology and Embryology, Nanjing Medical University, Nanjing, 211166, P.R. China;
| | - Ran Huo
- From the ‡State Key Laboratory of Reproductive Medicine, Department of Histology and Embryology, Nanjing Medical University, Nanjing, 211166, P.R. China;
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9
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Hickford DE, Wong SFL, Frankenberg SR, Shaw G, Yu H, Chew KY, Renfree MB. Expression of STRA8 is conserved in therian mammals but expression of CYP26B1 differs between marsupials and mice. Biol Reprod 2017; 97:217-229. [DOI: 10.1093/biolre/iox083] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2017] [Accepted: 07/28/2017] [Indexed: 11/13/2022] Open
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10
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Arora R, Abby E, Ross ADJ, Cantu AV, Kissner MD, Castro V, Ho HYH, Livera G, Laird DJ. Meiotic onset is reliant on spatial distribution but independent of germ cell number in the mouse ovary. J Cell Sci 2016; 129:2493-9. [PMID: 27199373 DOI: 10.1242/jcs.189910] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2016] [Accepted: 05/13/2016] [Indexed: 01/09/2023] Open
Abstract
Mouse ovarian germ cells enter meiosis in a wave that propagates from anterior to posterior, but little is known about contribution of germ cells to initiation or propagation of meiosis. In a Ror2 mutant with diminished germ cell number and migration, we find that overall timing of meiotic initiation is delayed at the population level. We use chemotherapeutic depletion to exclude a profoundly reduced number of germ cells as a cause for meiotic delay. We rule out sex reversal or failure to specify somatic support cells as contributors to the meiotic phenotype. Instead, we find that anomalies in the distribution of germ cells as well as gonad shape in mutants contribute to aberrant initiation of meiosis. Our analysis supports a model of meiotic initiation via diffusible signal(s), excludes a role for germ cells in commencing the meiotic wave and furnishes the first phenotypic demonstration of the wave of meiotic entry. Finally, our studies underscore the importance of considering germ cell migration defects while studying meiosis to discern secondary effects resulting from positioning versus primary meiotic entry phenotypes.
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Affiliation(s)
- Ripla Arora
- Department of Ob/Gyn and Reproductive Sciences, Eli and Edythe Broad Center for Regeneration Medicine and Stem Cell Research, University of California, San Francisco, 35 Medical Center Way, San Francisco, CA 94143, USA
| | - Emilie Abby
- University Paris Diderot, Sorbonne Paris Cite, Laboratory of Development of the Gonads; CEA, DSV, iRCM, SCSR, LDG; INSERM, Unit of Genetic Stability, Stem cells and Radiation, UMR-967; University Paris-Sud, Fontenay-aux-Roses F-92265, France
| | - Adam D J Ross
- Department of Ob/Gyn and Reproductive Sciences, Eli and Edythe Broad Center for Regeneration Medicine and Stem Cell Research, University of California, San Francisco, 35 Medical Center Way, San Francisco, CA 94143, USA
| | - Andrea V Cantu
- Department of Ob/Gyn and Reproductive Sciences, Eli and Edythe Broad Center for Regeneration Medicine and Stem Cell Research, University of California, San Francisco, 35 Medical Center Way, San Francisco, CA 94143, USA
| | - Michael D Kissner
- Department of Ob/Gyn and Reproductive Sciences, Eli and Edythe Broad Center for Regeneration Medicine and Stem Cell Research, University of California, San Francisco, 35 Medical Center Way, San Francisco, CA 94143, USA
| | - Vianca Castro
- Department of Ob/Gyn and Reproductive Sciences, Eli and Edythe Broad Center for Regeneration Medicine and Stem Cell Research, University of California, San Francisco, 35 Medical Center Way, San Francisco, CA 94143, USA
| | - Hsin-Yi Henry Ho
- Department of Cell Biology and Human Anatomy, University of California, Davis School of Medicine, 4422 Tupper Hall, Davis, CA 95616, USA
| | - Gabriel Livera
- University Paris Diderot, Sorbonne Paris Cite, Laboratory of Development of the Gonads; CEA, DSV, iRCM, SCSR, LDG; INSERM, Unit of Genetic Stability, Stem cells and Radiation, UMR-967; University Paris-Sud, Fontenay-aux-Roses F-92265, France
| | - Diana J Laird
- Department of Ob/Gyn and Reproductive Sciences, Eli and Edythe Broad Center for Regeneration Medicine and Stem Cell Research, University of California, San Francisco, 35 Medical Center Way, San Francisco, CA 94143, USA
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11
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Abstract
Germ cells are the precursors of the sperm and oocytes and hence are critical for survival of the species. In mammals, they are specified during fetal life, migrate to the developing gonads and then undergo a critical period during which they are instructed, by the soma, to adopt the appropriate sexual fate. In a fetal ovary, germ cells enter meiosis and commit to oogenesis, whereas in a fetal testis, they avoid entry into meiosis and instead undergo mitotic arrest and mature toward spermatogenesis. Here, we discuss what we know so far about the regulation of sex-specific differentiation of germ cells, considering extrinsic molecular cues produced by somatic cells, as well as critical intrinsic changes within the germ cells. This review focuses almost exclusively on our understanding of these events in the mouse model.
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Affiliation(s)
| | - Josephine Bowles
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, QLD 4072, Australia
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12
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Rossitto M, Philibert P, Poulat F, Boizet-Bonhoure B. Molecular events and signalling pathways of male germ cell differentiation in mouse. Semin Cell Dev Biol 2015; 45:84-93. [PMID: 26454096 DOI: 10.1016/j.semcdb.2015.09.014] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2015] [Accepted: 09/22/2015] [Indexed: 12/15/2022]
Abstract
Germ cells, the precursors of gametes, represent a unique cell lineage that is able to differentiate into spermatozoa or oocytes depending on the chromosomal sex of the organism. In the mammalian embryonic gonad, commitment to oogenesis involves pre-meiotic DNA replication and entry into the first meiotic division; whereas, commitment to spermatogenesis involves inhibition of meiotic initiation, suppression of pluripotency, mitotic arrest and expression of specific markers that will control the development of the male germ cells. The crucial decision made by the germ line to commit to either a male or a female fate has been partially explained by genetic and ex vivo studies in mice which have implicated a complex network of regulatory genes, numerous factors and pathways. Besides the reproductive failure that may follow a deregulation of this complex network, the germ cells may, in view of their proliferative and pluripotent nature, act as precursors of potential malignant transformation and as putative targets for exogenous environmental compounds. Our review summarizes and discusses recent developments that have improved our understanding on how germ cell precursors are committed to a male or a female cell fate in the mouse gonad.
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Affiliation(s)
- Moïra Rossitto
- Genetic and Development Department, Institute of Human Genetics, CNRS UPR1142, Montpellier, France.
| | - Pascal Philibert
- Genetic and Development Department, Institute of Human Genetics, CNRS UPR1142, Montpellier, France.
| | - Francis Poulat
- Genetic and Development Department, Institute of Human Genetics, CNRS UPR1142, Montpellier, France.
| | - Brigitte Boizet-Bonhoure
- Genetic and Development Department, Institute of Human Genetics, CNRS UPR1142, Montpellier, France.
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13
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Wu Q, Fukuda K, Weinstein M, Graff JM, Saga Y. SMAD2 and p38 signaling pathways act in concert to determine XY primordial germ cell fate in mice. Development 2015; 142:575-86. [PMID: 25605784 DOI: 10.1242/dev.119446] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The sex of primordial germ cells (PGCs) is determined in developing gonads on the basis of cues from somatic cells. In XY gonads, sex-determining region Y (SRY) triggers fibroblast growth factor 9 (FGF9) expression in somatic cells. FGF signaling, together with downstream nodal/activin signaling, promotes male differentiation in XY germ cells by suppressing retinoic acid (RA)-dependent meiotic entry and inducing male-specific genes. However, the mechanism by which nodal/activin signaling regulates XY PGC fate is unknown. We uncovered the roles of SMAD2/3 and p38 MAPK, the putative downstream factors of nodal/activin signaling, in PGC sexual fate decision. We found that conditional deletion of Smad2, but not Smad3, from XY PGCs led to a loss of male-specific gene expression. Moreover, suppression of RA signaling did not rescue male-specific gene expression in Smad2-mutant testes, indicating that SMAD2 signaling promotes male differentiation in a RA-independent manner. By contrast, we found that p38 signaling has an important role in the suppression of RA signaling. The Smad2 deletion did not disrupt the p38 signaling pathway even though Nodal expression was significantly reduced, suggesting that p38 was not regulated by nodal signaling in XY PGCs. Additionally, the inhibition of p38 signaling in the Smad2-mutant testes severely impeded XY PGC differentiation and induced meiosis. In conclusion, we propose a model in which p38 and SMAD2 signaling coordinate to determine the sexual fate of XY PGCs.
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Affiliation(s)
- Quan Wu
- Department of Genetics, SOKENDAI, Yata 1111, Mishima 411-8540, Japan Division of Mammalian Development, National Institute of Genetics, Yata 1111, Mishima 411-8540, Japan
| | - Kurumi Fukuda
- Department of Genetics, SOKENDAI, Yata 1111, Mishima 411-8540, Japan Division of Mammalian Development, National Institute of Genetics, Yata 1111, Mishima 411-8540, Japan
| | - Michael Weinstein
- Department of Molecular Genetics and Division of Human Cancer Genetics, Ohio State University, 484 W. 12th Avenue, Columbus, OH 43210, USA
| | - Jonathan M Graff
- Department of Molecular Biology, University of Texas Southwestern Medical Center, 6000 Harry Hines Boulevard, NB5.118, Dallas, TX 75390, USA
| | - Yumiko Saga
- Department of Genetics, SOKENDAI, Yata 1111, Mishima 411-8540, Japan Division of Mammalian Development, National Institute of Genetics, Yata 1111, Mishima 411-8540, Japan
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14
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Moniot B, Ujjan S, Champagne J, Hirai H, Aritake K, Nagata K, Dubois E, Nidelet S, Nakamura M, Urade Y, Poulat F, Boizet-Bonhoure B. Prostaglandin D2 acts through the Dp2 receptor to influence male germ cell differentiation in the foetal mouse testis. Development 2014; 141:3561-71. [DOI: 10.1242/dev.103408] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Through intercellular signalling, the somatic compartment of the foetal testis is able to program primordial germ cells to undergo spermatogenesis. Fibroblast growth factor 9 and several members of the transforming growth factor β superfamily are involved in this process in the foetal testis, counteracting the induction of meiosis by retinoic acid and activating germinal mitotic arrest. Here, using in vitro and in vivo approaches, we show that prostaglandin D2 (PGD2), which is produced through both L-Pgds and H-Pgds enzymatic activities in the somatic and germ cell compartments of the foetal testis, plays a role in mitotic arrest in male germ cells by activating the expression and nuclear localization of the CDK inhibitor p21Cip1 and by repressing pluripotency markers. We show that PGD2 acts through its Dp2 receptor, at least in part through direct effects in germ cells, and contributes to the proper differentiation of male germ cells through the upregulation of the master gene Nanos2. Our data identify PGD2 signalling as an early pathway that acts in both paracrine and autocrine manners, and contributes to the differentiation of germ cells in the foetal testis.
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Affiliation(s)
- Brigitte Moniot
- Genetic and Development department, Institute of Human Genetics, CNRS UPR1142, Montpellier 34094, Cedex 05, France
| | - Safdar Ujjan
- Genetic and Development department, Institute of Human Genetics, CNRS UPR1142, Montpellier 34094, Cedex 05, France
| | - Julien Champagne
- Genetic and Development department, Institute of Human Genetics, CNRS UPR1142, Montpellier 34094, Cedex 05, France
| | - Hiroyuki Hirai
- Department of Advanced Technology and Development, BML, Matoba, Kawagoe, Saitama 350-1101, Japan
| | - Kosuke Aritake
- Department of Molecular Behavioral Biology, Osaka Bioscience Institute, Osaka 565-0874, Japan
| | - Kinya Nagata
- Department of Advanced Technology and Development, BML, Matoba, Kawagoe, Saitama 350-1101, Japan
| | - Emeric Dubois
- Plateforme MGX, Functional Genomic Institute, CNRS UMR 5203 – INSERM U 661, Montpellier 34094, Cedex 05, France
| | - Sabine Nidelet
- Plateforme MGX, Functional Genomic Institute, CNRS UMR 5203 – INSERM U 661, Montpellier 34094, Cedex 05, France
| | - Masataka Nakamura
- Human Gene Sciences Center, Tokyo Medical and Dental University, Yushima, Bunkyo-ku, Tokyo 113-8510, Japan
| | - Yoshihiro Urade
- Department of Molecular Behavioral Biology, Osaka Bioscience Institute, Osaka 565-0874, Japan
| | - Francis Poulat
- Genetic and Development department, Institute of Human Genetics, CNRS UPR1142, Montpellier 34094, Cedex 05, France
| | - Brigitte Boizet-Bonhoure
- Genetic and Development department, Institute of Human Genetics, CNRS UPR1142, Montpellier 34094, Cedex 05, France
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15
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Poulain M, Frydman N, Tourpin S, Muczynski V, Mucsynski V, Souquet B, Benachi A, Habert R, Rouiller-Fabre V, Livera G. Involvement of doublesex and mab-3-related transcription factors in human female germ cell development demonstrated by xenograft and interference RNA strategies. Mol Hum Reprod 2014; 20:960-71. [PMID: 25082981 DOI: 10.1093/molehr/gau058] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
We identified three doublesex and mab-3-related transcription factors (DMRT) that were sexually differentially expressed in human fetal gonads and present in the ovaries at the time of meiotic initiation. These were also identified in murine embryonic female germ cells. Among these, we focused on DMRTA2 (DMRT5), whose function is unknown in the developing gonads, and clarified its role in human female fetal germ cells, using an original xenograft model. Early human fetal ovaries (8-11 weeks post-fertilization) were grafted into nude mice. Grafted ovaries developed normally, with no apparent overt changes, when compared with ungrafted ovaries at equivalent developmental stages. Appropriate germ cell density, mitotic/meiotic transition, markers of meiotic progression and follicle formation were evident. Four weeks after grafting, mice were treated with siRNA, specifically targeting human DMRTA2 mRNA. DMRTA2 inhibition triggered an increase in undifferentiated FUT4-positive germ cells and a decrease in the percentage of meiotic γH2AX-positive germ cells, when compared with mice that were injected with control siRNA. Interestingly, the expression of markers associated with pre-meiotic germ cell differentiation was also impaired, as was the expression of DMRTB1 (DMRT6) and DMRTC2 (DMRT7). This study reveals, for the first time, the requirement of DMRTA2 for normal human female embryonic germ cell development. DMRTA2 appears to be necessary for proper differentiation of oogonia, prior to entry into meiosis, in the human species. Additionally, we developed a new model of organ xenografting, coupled with RNA interference, which provides a useful tool for genetic investigations of human germline development.
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Affiliation(s)
- Marine Poulain
- University Paris Diderot, Sorbonne Paris Cité, Laboratory of Development of the Gonads, Unit of Stem Cells and Radiation, UMR 967, Fontenay aux Roses F-92265, France CEA, DSV, iRCM, SCSR, LDG, Fontenay aux Roses F-92265, France INSERM, Unité 967, Fontenay aux Roses F-92265, France University Paris-Sud, UMR 967, Fontenay aux Roses F-92265, France AP-HP, University Paris-Sud, Reproductive Biology Unit, Clamart F-92140, France
| | - Nelly Frydman
- University Paris Diderot, Sorbonne Paris Cité, Laboratory of Development of the Gonads, Unit of Stem Cells and Radiation, UMR 967, Fontenay aux Roses F-92265, France CEA, DSV, iRCM, SCSR, LDG, Fontenay aux Roses F-92265, France INSERM, Unité 967, Fontenay aux Roses F-92265, France University Paris-Sud, UMR 967, Fontenay aux Roses F-92265, France AP-HP, University Paris-Sud, Reproductive Biology Unit, Clamart F-92140, France
| | - Sophie Tourpin
- University Paris Diderot, Sorbonne Paris Cité, Laboratory of Development of the Gonads, Unit of Stem Cells and Radiation, UMR 967, Fontenay aux Roses F-92265, France CEA, DSV, iRCM, SCSR, LDG, Fontenay aux Roses F-92265, France INSERM, Unité 967, Fontenay aux Roses F-92265, France University Paris-Sud, UMR 967, Fontenay aux Roses F-92265, France
| | - Vincent Muczynski
- University Paris Diderot, Sorbonne Paris Cité, Laboratory of Development of the Gonads, Unit of Stem Cells and Radiation, UMR 967, Fontenay aux Roses F-92265, France CEA, DSV, iRCM, SCSR, LDG, Fontenay aux Roses F-92265, France INSERM, Unité 967, Fontenay aux Roses F-92265, France University Paris-Sud, UMR 967, Fontenay aux Roses F-92265, France
| | - Vincent Mucsynski
- University Paris Diderot, Sorbonne Paris Cité, Laboratory of Development of the Gonads, Unit of Stem Cells and Radiation, UMR 967, Fontenay aux Roses F-92265, France CEA, DSV, iRCM, SCSR, LDG, Fontenay aux Roses F-92265, France INSERM, Unité 967, Fontenay aux Roses F-92265, France University Paris-Sud, UMR 967, Fontenay aux Roses F-92265, France
| | - Benoit Souquet
- University Paris Diderot, Sorbonne Paris Cité, Laboratory of Development of the Gonads, Unit of Stem Cells and Radiation, UMR 967, Fontenay aux Roses F-92265, France CEA, DSV, iRCM, SCSR, LDG, Fontenay aux Roses F-92265, France INSERM, Unité 967, Fontenay aux Roses F-92265, France University Paris-Sud, UMR 967, Fontenay aux Roses F-92265, France
| | - Alexandra Benachi
- AP-HP, University Paris-Sud, Department of Obstetrics and Gynecology, Clamart F-92140, France
| | - René Habert
- University Paris Diderot, Sorbonne Paris Cité, Laboratory of Development of the Gonads, Unit of Stem Cells and Radiation, UMR 967, Fontenay aux Roses F-92265, France CEA, DSV, iRCM, SCSR, LDG, Fontenay aux Roses F-92265, France INSERM, Unité 967, Fontenay aux Roses F-92265, France University Paris-Sud, UMR 967, Fontenay aux Roses F-92265, France
| | - Virginie Rouiller-Fabre
- University Paris Diderot, Sorbonne Paris Cité, Laboratory of Development of the Gonads, Unit of Stem Cells and Radiation, UMR 967, Fontenay aux Roses F-92265, France CEA, DSV, iRCM, SCSR, LDG, Fontenay aux Roses F-92265, France INSERM, Unité 967, Fontenay aux Roses F-92265, France University Paris-Sud, UMR 967, Fontenay aux Roses F-92265, France
| | - Gabriel Livera
- University Paris Diderot, Sorbonne Paris Cité, Laboratory of Development of the Gonads, Unit of Stem Cells and Radiation, UMR 967, Fontenay aux Roses F-92265, France CEA, DSV, iRCM, SCSR, LDG, Fontenay aux Roses F-92265, France INSERM, Unité 967, Fontenay aux Roses F-92265, France University Paris-Sud, UMR 967, Fontenay aux Roses F-92265, France
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16
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Progesterone regulates chicken embryonic germ cell meiotic initiation independent of retinoic acid signaling. Theriogenology 2014; 82:195-203. [PMID: 24786395 DOI: 10.1016/j.theriogenology.2014.03.021] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2013] [Revised: 03/22/2014] [Accepted: 03/22/2014] [Indexed: 12/15/2022]
Abstract
The signaling molecule retinoic acid (RA) is known to trigger germ cells to enter meiosis. However, RA may not be the only secreted inducer of meiosis. Our previous data indicate that luteinizing hormone also promotes germ cell meiotic initiation by upregulating 3βHSDII transcription. Here, using chicken embryos, we investigate the role of progesterone (P4) in regulating germ cell meiotic initiation. Progesterone treatment at embryonic Day 9.5 accelerated germ cell meiosis entry in the female chicken embryos. However, P4 treatment in vivo did no influence on testicular germ cells but triggered their meiotic initiation in the cultured testes. As treatment with an RA receptor (RAR) inhibitor did not block the stimulatory effect of P4 on germ cell meiotic initiation, this P4 stimulatory effect seems to be independent of RAR-mediated signaling. The abundance of RA metabolism-related enzymes and RAR (RARβ) mRNAs did not differ significantly between P4-treated and control individuals. The RA concentration in the ovaries remained unchanged by P4 treatment in vivo. Because no inhibition by the P4 receptor (PR) nuclear receptor antagonist mifepristone on P4 effect was observed in either in vitro or in vivo experiments, the effect of P4 on germ cell meiotic initiation is probably mediated by membrane PRs (mPR). The mPRα, mPRβ, and mPRγ mRNAs were all expressed in the embryonic ovaries. The expression of mPRα and mPRβ was higher than that of mPRγ. Immunohistochemical results showed that mPRα-positive cells were mainly scattered in the ovarian cortex area where most germ cells were distributed. The mPRβ-positive cells were widely distributed in the ovaries, and positive cells were clustered with a similar morphology to that of germ cell clusters. In conclusion, P4 may regulate embryonic germ cell meiotic initiation independent of RA signaling through the membrane PRs. This study provides a new insight into the mechanisms of germ cell meiotic initiation in the chicken.
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17
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Tanaka M. Vertebrate female germline--the acquisition of femaleness. WILEY INTERDISCIPLINARY REVIEWS-DEVELOPMENTAL BIOLOGY 2013; 3:231-8. [PMID: 24896659 DOI: 10.1002/wdev.131] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2011] [Revised: 08/29/2013] [Accepted: 10/09/2013] [Indexed: 01/16/2023]
Abstract
The cellular and molecular characteristics of female germ cells have primarily been studied in the mammalian ovary. In most female mammals, all primordial germ cells (PGCs) develop into oocytes early during ovary formation, and germline stem cells are few in number or absent in postnatal ovaries (Lei L, Spradling AC. Female mice lack adult germ-line stem cells but sustain oogenesis using stable primordial follicles. Proc Natl Acad Sci USA 2013, 110:8585-8590). Research efforts in the field have largely focused on meiosis and follicular development, but a fundamental question regarding establishment of femaleness, which is very important to understand the 'female' germline, has not been discussed sufficiently. Recent work has revealed the presence of germline stem cells in the vertebrate ovary, using the teleost fish, medaka (Oryzias latipes) (Nakamura S, Kobayashi K, Nishimura T, Higashijima S, Tanaka, M. Identification of germline stem cells in the ovary of teleost medaka. Science 2010, 328:1561-1563). This discovery allows direct comparison between female and male germline stem cells and raises an interesting and heretofore unaddressed issue regarding femaleness of germline stem cells. In this article, the germ cell behavior in the ovaries of different species is reviewed and compared, the molecular mechanisms underlying the generation of female germ cells are discussed, and the relationship between female germ cells and the surrounding somatic cells is examined.
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Affiliation(s)
- Minoru Tanaka
- Laboratory of Molecular Genetics for Reproduction, National Institute for Basic Biology, Okazaki, Japan
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18
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MEIOB targets single-strand DNA and is necessary for meiotic recombination. PLoS Genet 2013; 9:e1003784. [PMID: 24068956 PMCID: PMC3778009 DOI: 10.1371/journal.pgen.1003784] [Citation(s) in RCA: 79] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2013] [Accepted: 07/25/2013] [Indexed: 11/19/2022] Open
Abstract
Meiotic recombination is a mandatory process for sexual reproduction. We identified a protein specifically implicated in meiotic homologous recombination that we named: meiosis specific with OB domain (MEIOB). This protein is conserved among metazoan species and contains single-strand DNA binding sites similar to those of RPA1. Our studies in vitro revealed that both recombinant and endogenous MEIOB can be retained on single-strand DNA. Those in vivo demonstrated the specific expression of Meiob in early meiotic germ cells and the co-localization of MEIOB protein with RPA on chromosome axes. MEIOB localization in Dmc1 (-/-) spermatocytes indicated that it accumulates on resected DNA. Homologous Meiob deletion in mice caused infertility in both sexes, due to a meiotic arrest at a zygotene/pachytene-like stage. DNA double strand break repair and homologous chromosome synapsis were impaired in Meiob (-/-) meiocytes. Interestingly MEIOB appeared to be dispensable for the initial loading of recombinases but was required to maintain a proper number of RAD51 and DMC1 foci beyond the zygotene stage. In light of these findings, we propose that RPA and this new single-strand DNA binding protein MEIOB, are essential to ensure the proper stabilization of recombinases which is required for successful homology search and meiotic recombination.
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He B, Mi Y, Zhang C. Gonadotropins regulate ovarian germ cell mitosis/meiosis decision in the embryonic chicken. Mol Cell Endocrinol 2013; 370:32-41. [PMID: 23422072 DOI: 10.1016/j.mce.2013.02.010] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/17/2012] [Revised: 02/02/2013] [Accepted: 02/11/2013] [Indexed: 11/24/2022]
Abstract
Gonadotropins are required for gametogenesis but in embryonic gonads this mechanism is not well understood. Here we use chicken embryos to investigate the mechanism that gonadotropins regulate the ovarian germ cell mitosis/meiosis decision. Treatment with follicle-stimulating hormone (FSH) delayed germ cell meiosis entry and promoted their proliferation. This action was blocked by an aromatase inhibitor. Treatment with luteinizing hormone (LH) accelerated germ cell meiosis entry and promoted transcription of 3βHSDII to increase progesterone (P4) production. In the cultured ovaries, P4 triggered meiotic initiation in germ cells. MiR181a, which acts to downregulate the NR6A1 transcript to inhibit the meiotic initiation, was upregulated by FSH and downregulated by LH. Collectively, gonadotropins regulate germ cells mitosis and meiotic initiation through steroid hormones and a miR181a-mediated pathway. In particularly, FSH delays germ cell meiosis entry and promotes cell proliferation via estrogen while LH accelerates the meiotic initiation via elevated P4 production.
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Affiliation(s)
- Bin He
- Key Laboratory of Molecular Animal Nutrition of the Ministry of Education and Department of Veterinary Medicine, College of Animal Sciences, Zhejiang University, Hangzhou 310058, PR China
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Wakeling SI, Miles DC, Western PS. Identifying disruptors of male germ cell development by small molecule screening in ex vivo gonad cultures. BMC Res Notes 2013; 6:168. [PMID: 23631647 PMCID: PMC3655070 DOI: 10.1186/1756-0500-6-168] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2013] [Accepted: 04/18/2013] [Indexed: 11/10/2022] Open
Abstract
Background Germ cell development involves formation of the spermatogenic or oogenic lineages from the bipotential primordial germ cells. Signaling mechanisms in the fetal testis and ovary determine whether germ cells enter the male or female developmental pathway, respectively. These signaling processes underpin an important phase of germ cell development, disruption of which can lead to failed germ cell function resulting in infertility or the formation of germ cell tumours. Findings In this study we have developed a small molecule screening protocol combined with flow cytometry to identify signaling pathways that direct male-specific development of germ cells. Here we provide a detailed method for this screening protocol, which we have used to identify signaling pathways important for male germ cell development. Conclusion This method will be of particular use in screening inhibitors of signaling pathways, endocrine disruptors or other chemicals for their ability to disrupt testis and germ cell development, thereby providing insight into testicular dysgenesis and factors underlying poor male reproductive health.
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Affiliation(s)
- Stephanie I Wakeling
- Monash Institute of Medical Research, Monash University, Clayton, 27-31 Wright St, Clayton, VIC, 3168, Australia
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21
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Mu X, Wen J, Guo M, Wang J, Li G, Wang Z, Wang Y, Teng Z, Cui Y, Xia G. Retinoic acid derived from the fetal ovary initiates meiosis in mouse germ cells. J Cell Physiol 2013; 228:627-39. [PMID: 22886539 DOI: 10.1002/jcp.24172] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2012] [Accepted: 07/31/2012] [Indexed: 11/11/2022]
Abstract
Meiotic initiation of germ cells at 13.5 dpc (days post-coitus) indicates female sex determination in mice. Recent studies reveal that mesonephroi-derived retinoic acid (RA) is the key signal for induction of meiosis. However, whether the mesonephroi is dispensable for meiosis is unclear and the role of the ovary in this meiotic process remains to be clarified. This study provides data that RA derived from fetal ovaries is sufficient to induce germ cell meiosis in a fetal ovary culture system. When fetal ovaries were collected from 11.5 to 13.5 dpc fetuses, isolated and cultured in vitro, germ cells enter meiosis in the absence of mesonephroi. To exclude RA sourcing from mesonephroi, 11.5 dpc urogenital ridges (UGRs; mesonephroi and ovary complexes) were treated with diethylaminobenzaldehyde (DEAB) to block retinaldehyde dehydrogenase (RALDH) activity in the mesonephros and the ovary. Meiosis occurred when DEAB was withdrawn and the mesonephros was removed 2 days later. Furthermore, RALDH1, rather than RALDH2, serves as the major RA synthetase in UGRs from 12.5 to 15.5 dpc. DEAB treatment to the ovary alone was able to block germ cell meiotic entry. We also found that exogenously supplied RA dose-dependently reduced germ cell numbers in ovaries by accelerating the entry into meiosis. These results suggest that ovary-derived RA is responsible for meiosis initiation.
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Affiliation(s)
- Xinyi Mu
- State Key Laboratory of Agro-biotechnology, College of Biological Science, China Agricultural University, Beijing, China
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22
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Miles DC, Wakeling SI, Stringer JM, van den Bergen JA, Wilhelm D, Sinclair AH, Western PS. Signaling through the TGF beta-activin receptors ALK4/5/7 regulates testis formation and male germ cell development. PLoS One 2013; 8:e54606. [PMID: 23342175 PMCID: PMC3546992 DOI: 10.1371/journal.pone.0054606] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2012] [Accepted: 12/14/2012] [Indexed: 01/19/2023] Open
Abstract
The developing testis provides an environment that nurtures germ cell development, ultimately ensuring spermatogenesis and fertility. Impacts on this environment are considered to underlie aberrant germ cell development and formation of germ cell tumour precursors. The signaling events involved in testis formation and male fetal germ cell development remain largely unknown. Analysis of knockout mice lacking single Tgfβ family members has indicated that Tgfβ's are not required for sex determination. However, due to functional redundancy, it is possible that additional functions for these ligands in gonad development remain to be discovered. Using FACS purified gonadal cells, in this study we show that the genes encoding Activin's, TGFβ's, Nodal and their respective receptors, are expressed in sex and cell type specific patterns suggesting particular roles in testis and germ cell development. Inhibition of signaling through the receptors ALK4, ALK5 and ALK7, and ALK5 alone, demonstrated that TGFβ signaling is required for testis cord formation during the critical testis-determining period. We also show that signaling through the Activin/NODAL receptors, ALK4 and ALK7 is required for promoting differentiation of male germ cells and their entry into mitotic arrest. Finally, our data demonstrate that Nodal is specifically expressed in male germ cells and expression of the key pluripotency gene, Nanog was significantly reduced when signaling through ALK4/5/7 was blocked. Our strategy of inhibiting multiple Activin/NODAL/TGFβ receptors reduces the functional redundancy between these signaling pathways, thereby revealing new and essential roles for TGFβ and Activin signaling during testis formation and male germ cell development.
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Affiliation(s)
- Denise C. Miles
- Centre for Reproduction and Development, Monash Institute of Medical Research, Monash University, Clayton, Victoria, Australia
| | - Stephanie I. Wakeling
- Centre for Reproduction and Development, Monash Institute of Medical Research, Monash University, Clayton, Victoria, Australia
| | - Jessica M. Stringer
- Centre for Reproduction and Development, Monash Institute of Medical Research, Monash University, Clayton, Victoria, Australia
| | - Jocelyn A. van den Bergen
- Department of Paediatrics, University of Melbourne, Murdoch Childrens Research Institute, Royal Children's Hospital, Parkville, Victoria, Australia
| | - Dagmar Wilhelm
- Department of Anatomy and Developmental Biology, Monash University, Clayton, Victoria, Australia
| | - Andrew H. Sinclair
- Department of Paediatrics, University of Melbourne, Murdoch Childrens Research Institute, Royal Children's Hospital, Parkville, Victoria, Australia
| | - Patrick S. Western
- Centre for Reproduction and Development, Monash Institute of Medical Research, Monash University, Clayton, Victoria, Australia
- * E-mail:
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23
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Bowles J, Koopman P. Precious Cargo: Regulation of Sex-Specific Germ Cell Development in Mice. Sex Dev 2013; 7:46-60. [DOI: 10.1159/000342072] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
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Muczynski V, Lecureuil C, Messiaen S, Guerquin MJ, N’Tumba-Byn T, Moison D, Hodroj W, Benjelloun H, Baijer J, Livera G, Frydman R, Benachi A, Habert R, Rouiller-Fabre V. Cellular and molecular effect of MEHP Involving LXRα in human fetal testis and ovary. PLoS One 2012; 7:e48266. [PMID: 23118965 PMCID: PMC3484128 DOI: 10.1371/journal.pone.0048266] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2012] [Accepted: 09/21/2012] [Indexed: 01/26/2023] Open
Abstract
Background Phthalates have been shown to have reprotoxic effects in rodents and human during fetal life. Previous studies indicate that some members of the nuclear receptor (NR) superfamilly potentially mediate phthalate effects. This study aimed to assess if expression of these nuclear receptors are modulated in the response to MEHP exposure on the human fetal gonads in vitro. Methodology/Principal Findings Testes and ovaries from 7 to 12 gestational weeks human fetuses were exposed to 10−4M MEHP for 72 h in vitro. Transcriptional level of NRs and of downstream genes was then investigated using TLDA (TaqMan Low Density Array) and qPCR approaches. To determine whether somatic or germ cells of the testis are involved in the response to MEHP exposure, we developed a highly efficient cytometric germ cell sorting approach. In vitro exposure of fetal testes and ovaries to MEHP up-regulated the expression of LXRα, SREBP members and of downstream genes involved in the lipid and cholesterol synthesis in the whole gonad. In sorted testicular cells, this effect is only observable in somatic cells but not in the gonocytes. Moreover, the germ cell loss induced by MEHP exposure, that we previously described, is restricted to the male gonad as oogonia density is not affected in vitro. Conclusions/Significance We evidenced for the first time that phthalate increases the levels of mRNA for LXRα, and SREBP members potentially deregulating lipids/cholesterol synthesis in human fetal gonads. Interestingly, this novel effect is observable in both male and female whereas the germ cell apoptosis is restricted to the male gonad. Furthermore, we presented here a novel and potentially very useful flow cytometric cell sorting method to analyse molecular changes in germ cells versus somatic cells.
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Affiliation(s)
- Vincent Muczynski
- University Paris Diderot, Sorbonne Paris Cité, Laboratory of Development of the Gonads, Unit of Stem Cells and Radiation, Fontenay-aux-Roses, France
- CEA, DSV, iRCM, SCSR, LDG, 92265 Fontenay-aux-Roses, France
- INSERM, Unité 967, F-92265, Fontenay aux Roses, France
| | - Charlotte Lecureuil
- University Paris Diderot, Sorbonne Paris Cité, Laboratory of Development of the Gonads, Unit of Stem Cells and Radiation, Fontenay-aux-Roses, France
- CEA, DSV, iRCM, SCSR, LDG, 92265 Fontenay-aux-Roses, France
- INSERM, Unité 967, F-92265, Fontenay aux Roses, France
| | - Sébastien Messiaen
- University Paris Diderot, Sorbonne Paris Cité, Laboratory of Development of the Gonads, Unit of Stem Cells and Radiation, Fontenay-aux-Roses, France
- CEA, DSV, iRCM, SCSR, LDG, 92265 Fontenay-aux-Roses, France
- INSERM, Unité 967, F-92265, Fontenay aux Roses, France
| | - Marie-Justine Guerquin
- University Paris Diderot, Sorbonne Paris Cité, Laboratory of Development of the Gonads, Unit of Stem Cells and Radiation, Fontenay-aux-Roses, France
- CEA, DSV, iRCM, SCSR, LDG, 92265 Fontenay-aux-Roses, France
- INSERM, Unité 967, F-92265, Fontenay aux Roses, France
| | - Thierry N’Tumba-Byn
- University Paris Diderot, Sorbonne Paris Cité, Laboratory of Development of the Gonads, Unit of Stem Cells and Radiation, Fontenay-aux-Roses, France
- CEA, DSV, iRCM, SCSR, LDG, 92265 Fontenay-aux-Roses, France
- INSERM, Unité 967, F-92265, Fontenay aux Roses, France
| | - Delphine Moison
- University Paris Diderot, Sorbonne Paris Cité, Laboratory of Development of the Gonads, Unit of Stem Cells and Radiation, Fontenay-aux-Roses, France
- CEA, DSV, iRCM, SCSR, LDG, 92265 Fontenay-aux-Roses, France
- INSERM, Unité 967, F-92265, Fontenay aux Roses, France
| | - Wassim Hodroj
- University Paris Diderot, Sorbonne Paris Cité, Laboratory of Development of the Gonads, Unit of Stem Cells and Radiation, Fontenay-aux-Roses, France
- CEA, DSV, iRCM, SCSR, LDG, 92265 Fontenay-aux-Roses, France
- INSERM, Unité 967, F-92265, Fontenay aux Roses, France
| | - Hinde Benjelloun
- Flow Cytometry Facility, CEA – DSV/iRCM/SCSR, F-92265 Fontenay aux Roses, France
| | - Jan Baijer
- Flow Cytometry Facility, CEA – DSV/iRCM/SCSR, F-92265 Fontenay aux Roses, France
| | - Gabriel Livera
- University Paris Diderot, Sorbonne Paris Cité, Laboratory of Development of the Gonads, Unit of Stem Cells and Radiation, Fontenay-aux-Roses, France
- CEA, DSV, iRCM, SCSR, LDG, 92265 Fontenay-aux-Roses, France
- INSERM, Unité 967, F-92265, Fontenay aux Roses, France
| | - René Frydman
- Service de Gynécologie-Obstétrique, Hôpital A. Béclère,- Université Paris Sud, F-92141 Clamart, France
| | - Alexandra Benachi
- Service de Gynécologie-Obstétrique, Hôpital A. Béclère,- Université Paris Sud, F-92141 Clamart, France
| | - René Habert
- University Paris Diderot, Sorbonne Paris Cité, Laboratory of Development of the Gonads, Unit of Stem Cells and Radiation, Fontenay-aux-Roses, France
- CEA, DSV, iRCM, SCSR, LDG, 92265 Fontenay-aux-Roses, France
- INSERM, Unité 967, F-92265, Fontenay aux Roses, France
| | - Virginie Rouiller-Fabre
- University Paris Diderot, Sorbonne Paris Cité, Laboratory of Development of the Gonads, Unit of Stem Cells and Radiation, Fontenay-aux-Roses, France
- CEA, DSV, iRCM, SCSR, LDG, 92265 Fontenay-aux-Roses, France
- INSERM, Unité 967, F-92265, Fontenay aux Roses, France
- * E-mail:
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25
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The involvement of proliferation and apoptosis in the early human gonad development. J Mol Histol 2012; 44:55-63. [PMID: 23070517 DOI: 10.1007/s10735-012-9455-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2012] [Accepted: 10/07/2012] [Indexed: 10/27/2022]
Abstract
Distributions of the Ki-67, TP53, caspase-3 and AIFM1 markers were histologically investigated in the 5th to 9th week developing gonads of 12 human conceptuses using immunohistochemical and immunofluorescence methods. Between the 5th and 8th developmental week, proliferation gradually increased in the surface gonad epithelium (26-52 %) and stroma (19-42 %), but then slightly decreased in the surface epithelium (35 %) during the early foetal period. In medulla, low proliferation activity decreased from 15 to 12 % between the 7th and 9th week. At earliest stages of gonadal development, primordial germ cells (PGC) were only rarely TP53 positive. In the 7th and 8th week, almost all PGC-s displayed TP53 positivity, while their number decreased in early fetal period. During the investigated period, caspase-3 reactivity gradually decreased in surface epithelium, while it increased in PGC and medulla of developing gonad AIFM1-positivity first appeared in surface gonad epithelium and then predominantly in PCG-s while caspase-3 characterized different cell populations within the developing gonad. AIFM1 and caspase-3 co-localized only during the migration of PCG-s. The number and distribution of Ki-67, TP53, caspase-3 and AIFM1 reacting cells changed coincidently with development end regression of the sex cords in indifferent and early fetal gonad. Our results indicate that the number of PGC might be controlled by balance of TP53 and AIFM1, leading to caspase-3 independent cell death. Other cell populations are probably eliminated by caspase-3-dependent cell death. Both pathways of cell death seem to operate during early human gonad development, while their intensity varies depending on the cell type and developmental period analysed.
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Jørgensen A, Nielsen JE, Blomberg Jensen M, Græm N, Rajpert-De Meyts E. Analysis of meiosis regulators in human gonads: a sexually dimorphic spatio-temporal expression pattern suggests involvement of DMRT1 in meiotic entry. Mol Hum Reprod 2012; 18:523-34. [PMID: 22899867 DOI: 10.1093/molehr/gas030] [Citation(s) in RCA: 80] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
The mitosis-meiosis switch is a key event in the differentiation of germ cells. In humans, meiosis is initiated in fetal ovaries, whereas in testes meiotic entry is inhibited until puberty. The purpose of this study was to examine the expression pattern of meiosis regulators in human gonads and to investigate a possible role of DMRT1 in the regulation of meiotic entry. The expression pattern of DMRT1, STRA8, SCP3, DMC1, NANOS3, CYP26B1 and NANOS2 was investigated by RT-PCR and immunohistochemistry in a series of human testis samples from fetal life to adulthood, and in fetal ovaries. DMRT1 was expressed in testes throughout development but with marked spatio-temporal changes. At the early fetal period of 8-20 gestational weeks (GW) and at infantile mini-puberty, DMRT1 was predominantly expressed in Sertoli cells, whereas at later stages of gestation (22-40 GW), during childhood and in post-pubertal testes, DMRT1 was most abundant in spermatogonia, except in the A-dark type. In fetal ovaries, DMRT1 was detected in oogonia and oocytes until 20 GW, but was completely down-regulated following meiotic entry. STRA8, SCP3 and DMC1 were expressed mainly in oocytes and spermatogonia in accordance with their role in initiation and progression of meiosis. The putative meiosis inhibitors, CYP26B1 and NANOS2, were primarily expressed in Leydig cells and spermatocytes, respectively. In conclusion, the expression pattern of the investigated meiotic regulators is largely conserved in the human gonads compared with rodents, but with some minor differences, such as a stable expression of CYP26B1 in human fetal ovaries. The sexually dimorphic expression pattern of DMRT1 indicates a similar role in the mitosis-meiosis switch in human gonads as previously demonstrated in mice. The biological importance of the changes in expression of DMRT1 in Sertoli cells remains to be established, but it is consistent with DMRT1 reinforcing the inhibition of meiosis in the testis.
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Affiliation(s)
- Anne Jørgensen
- Department of Growth and Reproduction, University of Copenhagen, Blegdamsvej 9, Copenhagen DK-2100, Denmark
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27
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Souquet B, Tourpin S, Messiaen S, Moison D, Habert R, Livera G. Nodal signaling regulates the entry into meiosis in fetal germ cells. Endocrinology 2012; 153:2466-73. [PMID: 22396454 DOI: 10.1210/en.2011-2056] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
The mechanisms regulating the entry into meiosis in mammalian germ cells remain incompletely understood. We investigated the involvement of the TGF-β family members in fetal germ cell meiosis initiation. Nodal, a member of the TGF-β family, and its target genes are precociously expressed in embryonic gonads and show sexual dimorphism in favor of the developing testis. Nodal receptor genes, Acvr2a and Acvr2b, Alk4, and Tdgf1/Cripto, were identified in male germ cells. Nodal itself, Tdgf1, and Lefty1 and Lefty2 are targets of Nodal signaling and were all found specifically expressed in male germ cells. To elucidate the role of this signaling pathway, activin-like kinases that mediate TGF-β/Nodal/activin signaling were inhibited in 11.5 d postconception testis in organotypic culture. Activin-like kinases inhibition disrupted normal male germ cell development and induced germ cell entry into meiosis such as that observed in female germ cells at the equivalent stage. Interestingly Stra8, the gatekeeper of the mitotic/meiotic switch, was induced independently of any change of either Cyp26b1 or Fgf9 expression, the two genes currently identified as testicular meiotic inhibitors. On the other hand, recombinant Nodal significantly dampened Stra8 expression and germ cell meiosis in cultured 11.5 d postconception ovaries. Our results allowed us to propose for the first time an autocrine role of Nodal during the development of germ cells and indicate that members of the TGB-β family may reinforce the male fate and prevent meiosis in embryonic germ cells.
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Affiliation(s)
- Benoit Souquet
- Commissariat à l'Energie Atomique (CEA)/Direction des Science du Vivant (DSV), Institut de Radiobiologie Cellulaire et Moléculaire (iRCM), Service Cellules Souches et Radiation (SCSR), Laboratoire de Développement des Gonades (LDG), Université Paris Diderot, Sorbonne Paris Cité, France
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28
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Geyer CB, Saba R, Kato Y, Anderson AJ, Chappell VK, Saga Y, Eddy EM. Rhox13 is translated in premeiotic germ cells in male and female mice and is regulated by NANOS2 in the male. Biol Reprod 2012; 86:127. [PMID: 22190708 DOI: 10.1095/biolreprod.111.094938] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Male and female germ cells enter meiosis in response to an extrinsic cue by retinoic acid (RA), but the pathways downstream of RA signaling that regulate early gametogenesis remain uncertain. We identified a novel reproductive homeobox gene, Rhox13, transcribed in the prenatal ovary and testis beginning on Embryonic Day (E) 13.5. Translation of RHOX13 also begins in female germ cells on E13.5 but is suppressed in male germ cells until Postnatal Day 3. Translation of RHOX13 coincides with initiation of RA signaling in both male and female gonads in vivo but occurs precociously in neonatal testes exposed to RA in vitro or in fetal male germ cells when NANOS2 is absent in vivo. Conversely, RHOX13 translation in female germ cells is suppressed in the presence of ectopically induced NANOS2. These results strongly suggest that RHOX13 expression is regulated at a posttranscriptional step by direct interaction of NANOS2 with Rhox13 mRNA to suppress translation.
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Affiliation(s)
- Christopher B Geyer
- Gamete Biology Group, Laboratory of Reproductive and Developmental Toxicology, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, North Carolina, USA.
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Ohta K, Yamamoto M, Lin Y, Hogg N, Akiyama H, Behringer RR, Yamazaki Y. Male differentiation of germ cells induced by embryonic age-specific Sertoli cells in mice. Biol Reprod 2012; 86:112. [PMID: 22262692 PMCID: PMC3338658 DOI: 10.1095/biolreprod.111.095943] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2011] [Revised: 09/13/2011] [Accepted: 01/05/2012] [Indexed: 11/01/2022] Open
Abstract
Retinoic acid (RA) is a meiosis-inducing factor. Primordial germ cells (PGCs) in the developing ovary are exposed to RA, resulting in entry into meiosis. In contrast, PGCs in the developing testis enter mitotic arrest to differentiate into prospermatogonia. Sertoli cells express CYP26B1, an RA-metabolizing enzyme, providing a simple explanation for why XY PGCs do not initiate meios/is. However, regulation of entry into mitotic arrest is likely more complex. To investigate the mechanisms that regulate male germ cell differentiation, we cultured XX and XY germ cells at 11.5 and 12.5 days postcoitus (dpc) with an RA receptor inhibitor. Expression of Stra8, a meiosis initiation gene, was suppressed in all groups. However, expression of Dnmt3l, a male-specific gene, during embryogenesis was elevated but only in 12.5-dpc XY germ cells. This suggests that inhibiting RA signaling is not sufficient for male germ cell differentiation but that the male gonadal environment also contributes to this pathway. To define the influence of Sertoli cells on male germ cell differentiation, Sertoli cells at 12.5, 15.5, and 18.5 dpc were aggregated with 11.5 dpc PGCs, respectively. After culture, PGCs aggregated with 12.5 dpc Sertoli cells increased Nanos2 and Dnmt3l expression. Furthermore, these PGCs established male-specific methylation imprints of the H19 differentially methylated domains. In contrast, PGCs aggregated with Sertoli cells at late embryonic ages did not commit to the male pathway. These findings suggest that male germ cell differentiation is induced both by inhibition of RA signaling and by molecule(s) production by embryonic age-specific Sertoli cells.
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Affiliation(s)
- Kohei Ohta
- Institute for Biogenesis Research, John A. Burns School of Medicine, University of Hawaii, Hawaii, USA.
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30
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Griswold MD, Hogarth CA, Bowles J, Koopman P. Initiating meiosis: the case for retinoic acid. Biol Reprod 2012; 86:35. [PMID: 22075477 DOI: 10.1095/biolreprod.111.096610] [Citation(s) in RCA: 110] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
The requirement for vitamin A in reproduction and development was first determined from studies of nutritional deficiencies. Subsequent research has shown that embryonic development and both male and female reproduction are modulated by retinoic acid (RA), the active form of vitamin A. Because RA is active in multiple developmental systems, its synthesis, transport, and degradation are tightly regulated in different tissues. A growing body of evidence implicates RA as a requirement for the initiation of meiosis in both male and female mammals, resulting in a mechanistic model involving the interplay of RA, RA synthesis enzymes, RA receptors, and degradative cytochrome P450 enzymes in this system. Recently, that model has been challenged, prompting a review of the established paradigm. While it remains possible that additional molecules may be involved in regulating entry into meiosis, the weight of evidence supporting a key role for RA is incontrovertible.
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Affiliation(s)
- Michael D Griswold
- School of Molecular Biosciences, Washington State University, Pullman, 99164, USA.
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Gely-Pernot A, Raverdeau M, Célébi C, Dennefeld C, Feret B, Klopfenstein M, Yoshida S, Ghyselinck NB, Mark M. Spermatogonia differentiation requires retinoic acid receptor γ. Endocrinology 2012; 153:438-49. [PMID: 22045663 DOI: 10.1210/en.2011-1102] [Citation(s) in RCA: 92] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Vitamin A is instrumental to mammalian reproduction. Its metabolite, retinoic acid (RA), acts in a hormone-like manner through binding to and activating three nuclear receptor isotypes, RA receptor (RAR)α (RARA), RARβ, and RARγ (RARG). Here, we show that 1) RARG is expressed by A aligned (A(al)) spermatogonia, as well as during the transition from A(al) to A(1) spermatogonia, which is known to require RA; and 2) ablation of Rarg, either in the whole mouse or specifically in spermatogonia, does not affect meiosis and spermiogenesis but impairs the A(al) to A(1) transition in the course of some of the seminiferous epithelium cycles. Upon ageing, this phenomenon yields seminiferous tubules containing only spermatogonia and Sertoli cells. Altogether, our findings indicate that RARG cell-autonomously transduces, in undifferentiated spermatogonia of adult testes, a RA signal critical for spermatogenesis. During the prepubertal spermatogenic wave, the loss of RARG function can however be compensated by RARA, as indicated by the normal timing of appearance of meiotic cells in Rarg-null testes. Accordingly, RARG- and RARA-selective agonists are both able to stimulate Stra8 expression in wild-type prepubertal testes. Interestingly, inactivation of Rarg does not impair expression of the spermatogonia differentiation markers Kit and Stra8, contrary to vitamin A deficiency. This latter observation supports the notion that the RA-signaling pathway previously shown to operate in Sertoli cells also participates in spermatogonia differentiation.
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Affiliation(s)
- Aurore Gely-Pernot
- Institut de Génétique et de Biologie Moléculaire et Cellulaire, Institut National de Santé et de Recherche Médicale Unité 964, Centre National de Recherche Scientifique Unité Mixte de Recherche 7104, Université de Strasbourg, 67404 Illkirch, France
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Ross AC, Zolfaghari R. Cytochrome P450s in the regulation of cellular retinoic acid metabolism. Annu Rev Nutr 2011; 31:65-87. [PMID: 21529158 DOI: 10.1146/annurev-nutr-072610-145127] [Citation(s) in RCA: 195] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The active metabolite of vitamin A, retinoic acid (RA), is a powerful regulator of gene transcription. RA is also a therapeutic drug. The oxidative metabolism of RA by certain members of the cytochrome P450 (CYP) superfamily helps to maintain tissue RA concentrations within appropriate bounds. The CYP26 family--CYP26A1, CYP26B1, and CYP26C1--is distinguished by being both regulated by and active toward all-trans-RA (at-RA) while being expressed in different tissue-specific patterns. The CYP26A1 gene is regulated by multiple RA response elements. CYP26A1 is essential for embryonic development, whereas CYP26B1 is essential for postnatal survival as well as germ cell development. Enzyme kinetic studies have demonstrated that several CYP proteins are capable of metabolizing at-RA; however, it is likely that CYP26A1 plays a major role in RA clearance. Thus, pharmacological approaches to limiting the activity of CYP26 enzymes may extend the half-life of RA and could be useful clinically in the future.
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Affiliation(s)
- A Catharine Ross
- Department of Nutritional Sciences, Pennsylvania State University, University Park, PA 16802, USA.
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Le Bouffant R, Souquet B, Duval N, Duquenne C, Hervé R, Frydman N, Robert B, Habert R, Livera G. Msx1 and Msx2 promote meiosis initiation. Development 2011; 138:5393-402. [PMID: 22071108 DOI: 10.1242/dev.068452] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The mechanisms regulating germ line sex determination and meiosis initiation are poorly understood. Here, we provide evidence for the involvement of homeobox Msx transcription factors in foetal meiosis initiation in mammalian germ cells. Upon meiosis initiation, Msx1 and Msx2 genes are strongly expressed in the foetal ovary, possibly stimulated by soluble factors found there: bone morphogenetic proteins Bmp2 and Bmp4, and retinoic acid. Analysis of Msx1/Msx2 double mutant embryos revealed a majority of undifferentiated germ cells remaining in the ovary and, importantly, a decrease in the number of meiotic cells. In vivo, the Msx1/Msx2 double-null mutation prevented full activation of Stra8, a gene required for meiosis. In F9 cells, Msx1 can bind to Stra8 regulatory sequences and Msx1 overexpression stimulates Stra8 transcription. Collectively, our data demonstrate for the first time that some homeobox genes are required for meiosis initiation in the female germ line.
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Affiliation(s)
- Ronan Le Bouffant
- CEA, DSV/iRCM/SCSR/LDG, Laboratoire de Développement des Gonades, Unité Cellules Souches et Radiation, F-92265 Fontenay aux Roses, France
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Moniot B, Farhat A, Aritake K, Declosmenil F, Nef S, Eguchi N, Urade Y, Poulat F, Boizet-Bonhoure B. Hematopoietic prostaglandin D synthase (H-Pgds) is expressed in the early embryonic gonad and participates to the initial nuclear translocation of the SOX9 protein. Dev Dyn 2011; 240:2335-43. [DOI: 10.1002/dvdy.22726] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/03/2011] [Indexed: 01/03/2023] Open
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Childs AJ, Cowan G, Kinnell HL, Anderson RA, Saunders PTK. Retinoic Acid signalling and the control of meiotic entry in the human fetal gonad. PLoS One 2011; 6:e20249. [PMID: 21674038 PMCID: PMC3108594 DOI: 10.1371/journal.pone.0020249] [Citation(s) in RCA: 116] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2010] [Accepted: 04/28/2011] [Indexed: 12/24/2022] Open
Abstract
The development of mammalian fetal germ cells along oogenic or spermatogenic fate trajectories is dictated by signals from the surrounding gonadal environment. Germ cells in the fetal testis enter mitotic arrest, whilst those in the fetal ovary undergo sex-specific entry into meiosis, the initiation of which is thought to be mediated by selective exposure of fetal ovarian germ cells to mesonephros-derived retinoic acid (RA). Aspects of this model are hard to reconcile with the spatiotemporal pattern of germ cell differentiation in the human fetal ovary, however. We have therefore examined the expression of components of the RA synthesis, metabolism and signalling pathways, and their downstream effectors and inhibitors in germ cells around the time of the initiation of meiosis in the human fetal gonad. Expression of the three RA-synthesising enzymes, ALDH1A1, 2 and 3 in the fetal ovary and testis was equal to or greater than that in the mesonephros at 8–9 weeks gestation, indicating an intrinsic capacity within the gonad to synthesise RA. Using immunohistochemistry to detect RA receptors RARα, β and RXRα, we find germ cells to be the predominant target of RA signalling in the fetal human ovary, but also reveal widespread receptor nuclear localization indicative of signalling in the testis, suggesting that human fetal testicular germ cells are not efficiently shielded from RA by the action of the RA-metabolising enzyme CYP26B1. Consistent with this, expression of CYP26B1 was greater in the human fetal ovary than testis, although the sexually-dimorphic expression patterns of the germ cell-intrinsic regulators of meiotic initiation, STRA8 and NANOS2, appear conserved. Finally, we demonstrate that RA induces a two-fold increase in STRA8 expression in cultures of human fetal testis, but is not sufficient to cause widespread meiosis-associated gene expression. Together, these data indicate that while local production of RA within the fetal ovary may be important in regulating the onset of meiosis in the human fetal ovary, mechanisms other than CYP26B1-mediated metabolism of RA may exist to inhibit the entry of germ cells into meiosis in the human fetal testis.
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Affiliation(s)
- Andrew J Childs
- Medical Research Council Human Reproductive Sciences Unit, The Queen's Medical Research Institute, University of Edinburgh, Edinburgh, United Kingdom.
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Kumar S, Chatzi C, Brade T, Cunningham TJ, Zhao X, Duester G. Sex-specific timing of meiotic initiation is regulated by Cyp26b1 independent of retinoic acid signalling. Nat Commun 2011; 2:151. [PMID: 21224842 DOI: 10.1038/ncomms1136] [Citation(s) in RCA: 102] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2010] [Accepted: 11/15/2010] [Indexed: 01/26/2023] Open
Abstract
Sex-specific initiation of meiosis in the fetal ovary has been suggested to require retinoic acid (RA) for induction of Stra8, with expression of the RA-degrading enzyme Cyp26b1 in fetal testis delaying meiosis until postnatal development. In this study, we investigate Raldh2(-/-) mice lacking RA synthesis and signalling in mesonephros and adjacent gonad and reveal that Stra8 expression in the fetal ovary does not require RA signalling. In contrast to previous observations, we find that Stra8 is expressed in the absence of physiologically detectable levels of RA. Ketoconazole inhibition of Cyp26b1 in Raldh2(-/-) testis allows RA-independent induction of Stra8, but only when the mesonephros remains attached, pointing to a non-RA signal from the mesonephros that induces Stra8 in the adjacent gonad. These findings demonstrate that Cyp26b1 prevents the onset of meiosis by metabolizing a substrate other than RA that controls Stra8 expression, thus changing the paradigm for how studies on Cyp26 function are conducted.
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Affiliation(s)
- Sandeep Kumar
- Sanford-Burnham Medical Research Institute, Development and Aging Program, 10901 North Torrey Pines Road, La Jolla, California 92037, USA
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