Beatrice Mandon-Pepin

French National Institute for Agricultural Research, Lutetia Parisorum, Île-de-France, France

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Publications (53)104.35 Total impact

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    Agnes Bonnet · Bertrand Servin · Philippe Mulsant · Beatrice Mandon-Pepin
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    ABSTRACT: Background: The successful achievement of early ovarian folliculogenesis is important for fertility and reproductive life span. This complex biological process requires the appropriate expression of numerous genes at each developmental stage, in each follicular compartment. Relatively little is known at present about the molecular mechanisms that drive this process, and most gene expression studies have been performed in rodents and without considering the different follicular compartments. Results: We used RNA-seq technology to explore the sheep transcriptome during early ovarian follicular development in the two main compartments: oocytes and granulosa cells. We documented the differential expression of 3,015 genes during this phase and described the gene expression dynamic specific to these compartments. We showed that important steps occurred during primary/secondary transition in sheep. We also described the in vivo molecular course of a number of pathways. In oocytes, these pathways documented the chronology of the acquisition of meiotic competence, migration and cellular organization, while in granulosa cells they concerned adhesion, the formation of cytoplasmic projections and steroid synthesis. This study proposes the involvement in this process of several members of the integrin and BMP families. The expression of genes such as Kruppel-like factor 9 (KLF9) and BMP binding endothelial regulator (BMPER) was highlighted for the first time during early follicular development, and their proteins were also predicted to be involved in gene regulation. Finally, we selected a data set of 24 biomarkers that enabled the discrimination of early follicular stages and thus offer a molecular signature of early follicular growth. This set of biomarkers includes known genes such as SPO11 meiotic protein covalently bound to DSB (SPO11), bone morphogenetic protein 15 (BMP15) and WEE1 homolog 2 (S. pombe)(WEE2) which play critical roles in follicular development but other biomarkers are also likely to play significant roles in this process. Conclusions: To our knowledge, this is the first in vivo spatio-temporal exploration of transcriptomes derived from early follicles in sheep.
    Full-text · Article · Nov 2015 · PLoS ONE

  • No preview · Article · Oct 2015
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    DESCRIPTION: Topaz1 (Testis and Ovary-specific PAZ domain gene 1) is a germ cell specific gene highly conserved in vertebrates. The putative protein TOPAZ1 contains a PAZ domain, specifically found in PIWI, Argonaute and Zwille proteins. Consequently, Topaz1 is supposed to have a role during gametogenesis and may be involved in the piRNA pathway and contribute to silencing of transposable elements and maintenance of genome integrity. Here we report Topaz1 inactivation in mouse. Female fertility was not affected, but male sterility appeared exclusively in homozygous mutants in accordance with the high expression of Topaz1 in male germ cells. Pachytene Topaz1 – deficient spermatocytes progress through meiosis without either derepression of retrotransposons or MSCI dysfunction, but become arrested before the post-meiotic round spermatid stage with extensive apoptosis. Consequently, an absence of spermatids and spermatozoa was observed in Topaz1−/− testis. Histological analysis also revealed that disturbances of spermatogenesis take place between post natal days 15 and 20, during the first wave of male meiosis and before the generation of haploid germ cells. Transcriptomic analysis at these two stages showed that TOPAZ1 influences the expression of one hundred transcripts, most of which are up-regulated in mutant testis at post natal day 20. Our results also showed that 10% of these transcripts are long non-coding RNA. This suggests that a highly regulated balance of lncRNAs seems to be essential during spermatogenesis for induction of appropriate male gamete production.
    Full-text · Research · Sep 2015
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    ABSTRACT: Topaz1 (Testis and Ovary-specific PAZ domain gene 1) is a germ cell specific gene highly conserved in vertebrates. The putative protein TOPAZ1 contains a PAZ domain, specifically found in PIWI, Argonaute and Zwille proteins. Consequently, Topaz1 is supposed to have a role during gametogenesis and may be involved in the piRNA pathway and contribute to silencing of transposable elements and maintenance of genome integrity. Here we report Topaz1 inactivation in mouse. Female fertility was not affected, but male sterility appeared exclusively in homozygous mutants in accordance with the high expression of Topaz1 in male germ cells. Pachytene Topaz1-deficient spermatocytes progress through meiosis without either derepression of retrotransposons or MSCI dysfunction, but become arrested before the post-meiotic round spermatid stage with extensive apoptosis. Consequently, an absence of spermatids and spermatozoa was observed in Topaz1(-/-) testis. Histological analysis also revealed that disturbances of spermatogenesis take place between post natal days 15 and 20, during the first wave of male meiosis and before the generation of haploid germ cells. Transcriptomic analysis at these two stages showed that TOPAZ1 influences the expression of one hundred transcripts, most of which are up-regulated in mutant testis at post natal day 20. Our results also showed that 10% of these transcripts are long non-coding RNA. This suggests that a highly regulated balance of lncRNAs seems to be essential during spermatogenesis for induction of appropriate male gamete production.
    No preview · Article · Sep 2015 · Developmental Biology
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    ABSTRACT: Successful early folliculogenesis is crucial for female reproductive function. It requires appropriate gene specific expression of the different types of ovarian cells at different developmental stages. To date, most gene expression studies on the ovary were conducted in rodents and did not distinguish the type of cell. In mono-ovulating species, few studies have addressed gene expression profiles and mainly concerned human oocytes. We used a laser capture microdissection method combined with RNA-seq technology to explore the transcriptome in oocytes and granulosa cells (GCs) during development of the sheep ovarian follicle. We first documented the expression profile of 15 349 genes, then focused on the 5 129 genes showing differential expression between oocytes and GCs. Enriched functional categories such as oocyte meiotic arrest and GC steroid synthesis reflect two distinct cell fates. We identified the implication of GC signal transduction pathways such as SHH, WNT and RHO GTPase. In addition, signaling pathways (VEGF, NOTCH, IGF1, etc.) and GC transzonal projections suggest the existence of complex cell-cell interactions. Finally, we highlighted several transcription regulators and specifically expressed genes that likely play an important role in early folliculogenesis. To our knowledge, this is the first comprehensive exploration of transcriptomes derived from in vivo oocytes and GCs at key stages in early follicular development in sheep. Collectively, our data advance our understanding of early folliculogenesis in mono-ovulating species and will be a valuable resource for unraveling human ovarian dysfunction such as premature ovarian failure (POF).
    Full-text · Article · Dec 2013 · BMC Genomics
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    ABSTRACT: Alterations to the metabolic environment in utero can impact subsequent female reproductive performance. Here, we used a model of rabbits receiving a high fat diet (H diet) (7.7% fat and 0.2% cholesterol) or a control diet (C diet) (1.8% fat, no cholesterol) from 10 weeks of age up to mating at 27 weeks and throughout gestation and lactation. At weaning at 5 weeks of age, F1 female offspring were placed on either C or H diet, resulting in a total of 4 groups C/C, C/H, H/C and H/H diet. Female offspring were mated between 18 and 22 weeks of age and euthanized at 28 days of gestation. A few days before mating and/or just before euthanasia, F1 females were fasted overnight, weighed and blood sampled for steroids and biochemistry. Organs were weighed at euthanasia and ovaries were collected. C/H and H/H F1 offspring had higher cholesterol and HDL plasma concentrations, together with a higher fat mass compared to C/C does, reflecting the effect of the postnatal diet, but no effect of the antenatal diet was observed on most parameters. The number of primordial, primary and secondary follicles were not different between groups but a significantly higher number of atretic follicles was observed in the C/H (P<0.001) and in the H/C (P<0.001) compared to control C/C ovaries, demonstrating both an effect of pre- and post-natal maternal nutrition. These data indicated that both maternal and post-natal high fat diet may induce follicular apoptosis but in this model the reproduction was not affected.
    Full-text · Article · Dec 2013 · Journal of Developmental Origins of Health and Disease

  • No preview · Article · Oct 2013
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    ABSTRACT: Prophase I meiosis and follicle formation are two crucial events of the ovarian development, determining for the future female fertility. Disruption of these initial steps of folliculogenesis results in incomplete sexual development and may contribute to gonadal dysgenesis, infertility or ovarian cancer. Several environmental chemicals are known to affect these developmental processes in rodents following in utero exposure or in vitro culture. However, some mechanisms governing these processes differ between species and reproductive toxicity studies in rodent models correlate poorly with the human. For this reason, sheep are an alternative animal model with many relevant similarities to human ovarian development and to human toxicokinetics. The use of low doses of environmental pollutants close to those found in human biological fluids is crucial in order to mimic the real-life exposure conditions of human gonads. Our aims were: (i) to develop a long-term in vitro ovary organotypic culture allowing both meiosis initiation/progress and follicle morphogenesis/differentiation, and (ii) to evaluate the effects of MEHP (10-6M and 10-8M), PCB 101-118 (10 6M; 10 7M), MEHP + PCB101-118 and BPA (3.10-5M; 3.10-7M), on folliculogenesis and ovary gene expression by microarray analysis. Foetal ovaries were collected at 48dpc, 90dpc and 110dpc then cultured for 21 days in presence of growth/differentiation factors. After each period of culture, per each condition, ovarian fragments were split between histological examination and transcriptome analysis. We have established a foetal ovary culture system in sheep, able to: (i) initiate and maintain meiosis in oogonia, (ii) allow follicle transition and differentiation. Using this culture system, we have shown that in vitro exposure to environmental doses of MEHP and PCB 101-118, produced very few alterations in the sheep foetal ovary transcriptome. MEHP + PCB101-118 and BPA (3.10-7M) exposure at low doses induced less than 10 transcripts differentially expressed at any developmental stage. The dysregulated transcripts were specific for each stage of ovarian development. In contrast, BPA (3.10-5M) exposure resulted in alteration of a large number of transcripts, especially during prophase I meiosis. In conclusion, while BPA (3.10-5M) exposure induced more in vitro changes to foetal ovarian transcripts that other pollutants tested, none at environmental doses (10-7M and 10-8M) produced significant alterations both in transcriptome and ovarian morphology. This research was supported by EU grant (FP7; REEF #212885).
    No preview · Book · Jul 2013
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    ABSTRACT: Exposure of female fetuses to environmental chemicals (ECs) during pregnancy results in a disturbed ovarian adult phenotype. We investigated the influence of pre- and/or post-conception exposure to low-level mixtures of ECs on the structure and function of the fetal ovine ovary. We examined ovarian morphology, expression of oocyte and granulosa cell-specific genes and proteome. Female fetuses were collected at day 110 of gestation, from dams exposed continuously until, and after mating, by grazing in pastures treated with sewage sludge as a fertiliser (TT) or in control fields treated with inorganic fertiliser (CC). In addition, in a cross-over design, fetal ovaries were collected from dams maintained on sludge pastures up to the time of mating but then transferred to control pastures (TC) and, reciprocally, those transferred from control to treated pastures at mating (CT). On examination, the proportion of type 1a follicles (activating primordial follicles) was significantly lower in animals from the CT groups compared with CC and TT groups (P<0.05). Of the 23 ovarian gene transcripts studied, 14 were altered in the ovaries of exposed fetuses (CT, TC, and TT) relative to controls, with the largest number of changes observed in cross-exposure pattern groups (CT or TC). Continuous EC exposure (TT) produced fewer transcript alterations and only two genes (INHBA and GSN) presented differential profiles between CC and TT. Fetal ovarian proteome analysis (2-DE gels) showed, across all exposure groups, 86 differentially expressed protein spots compared to controls. Animals in the CT group exhibited the highest number (53) while TC and TT presented the same number of affected protein spots (42). Fetal ovarian proteins with altered expression included MVP (major vault protein) and several members of the heat-shock family (HSPA4L, HSP90AA1 and HSF1). The present findings indicate that continuous maternal EC exposure before and during gestation, are less deleterious for fetal ovarian development than a change in maternal EC exposure between pre and post-conception. The pathways by which the ovary responds to this chemical stress were common in TT, CT, TC exposed foetuses. In addition to the period of pregnancy, the pre-conception period appears also as crucial for conditioning long-term effects of EC exposure on ovarian development and primordial follicle reserve and hence future fertility.
    Full-text · Article · Jun 2013 · Molecular and Cellular Endocrinology
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    ABSTRACT: Our previous studies of sewage sludge exposures, and the literature, highlight polychlorinated bisphenols (PCB) and diethylhexyl phthalate (DEHP) as biologically active at environmental concentrations. We have demonstrated in sheep that a real-life cocktail of environmental chemicals, containing these chemicals, preferentially accumulate in the fetus and affects the development of the ovary.We therefore investigated the effects of dietary intake of DEHP, the two PCBs and a mixture of both, on sheep female reproductive development in vivo and in vitro. Ovaries were collected from day 140 foetal sheep foetuses exposed in-utero to DEHP and/or PCBs (congeners 101+118) and also control (vehicle). 54 ovaries distributed in four groups were included in this study and were analysed by histology and by transcriptomic analysis with a dedicated sheep microarray.There were no overall significant effects of any of the exposures on fetal ovarian follicle dynamics at day 140 compared with control fetuses. In DEHP-exposed ovaries, a total of 136 genes were differentially expressed between controls and exposed fetuses (FDR 5% and a fold-change >1.5). A greater number of genes were down-regulated (106/136) as compared to those that were up-regulated (30/136). A much smaller number of genes were significantly affected by PCB exposure; only 4 genes were differentially expressed. Surprisingly, the mixture DEHP+PCBs produced fewer changes than DEHP alone: 24 genes were differentially expressed (9 up, 13 down).In parallel, we have developed a long-term (20 days) organotypic culture system to investigate the histological and molecular effects of MEHP (the main metabolite of DEHP) and PCB101 & 118 on early ovarian development. In these culture experiments, MEHP and PCB 101 & 118 at 10-6 M or a combination of both and MEHP and PCB 101-118 at 10-8 M or combination of both were tested. Three stages of ovary development were investigated: meiosis (48-70dpc in sheep), primary follicle formation (90-110dpc) and follicle differentiation (110-130dpc). Very few genes were differentially expressed between controls and PCB, MEHP and mixture exposures. There were no significant differences in morphology or in oocyte or follicle numbers.In conclusion, a larger number of effects of exposure were observed in vivo than in vitro for the same compounds. This also suggests further reasons for caution in assessing developmental consequences of exposure to ECs in vitro.
    No preview · Article · May 2013
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    ABSTRACT: Excess of fat intake is dramatically increasing in women of childbearing age and results in numerous health complications, including reproductive disorders. Using rabbit does as a biomedical model, the aim of this study was to evaluate onset of puberty, endocrine responses to stimulation and ovarian follicular maturation in females fed a high fat high cholesterol diet (HH diet) from 10 weeks of age (i.e., 2 weeks before normal onset of puberty) or a control diet (C diet). Three experiments were performed, each including 8 treated (HH group) and 8 control (C group) does. In experiment 1, the endocrine response to Gonadotropin releasing hormone (GnRH) was evaluated at 13, 18 and 22 weeks of age. In experiment 2, the follicular population was counted in ovaries of adult females (18 weeks of age). In experiment 3, the LH response to mating and steroid profiles throughout gestation were evaluated at 18 weeks of age. Fetal growth was monitored by ultrasound and offspring birth weight was recorded. Data showed a significantly higher Luteinizing hormone (LH) response after induction of ovulation at 13 weeks of age in the HH group. There was no difference at 18 weeks, but at 22 weeks, the LH response to GnRH was significantly reduced in the HH group. The number of atretic follicles was significantly increased and the number of antral follicles significantly reduced in HH does vs. controls. During gestation, the HH diet induced intra-uterine growth retardation (IUGR). The HH diet administered from before puberty onwards affected onset of puberty, follicular growth, hormonal responses to breeding and GnRH stimulation in relation to age and lead to fetal IUGR.
    Full-text · Article · May 2013 · PLoS ONE
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    ABSTRACT: Ewes were exposed to sewage sludge-fertilised pastures in a study designed investigate pre-conceptual and/or gestational exposure to environmental chemicals. The in-utero impact on fetal thyroid morphology and function at day 110 (of 145) of pregnancy was then determined. Pre-conceptual exposure increased the relative thyroid organ weights in male fetuses. The number of thyroid follicles in thyroids of fetuses after pre-conceptual or gestational exposure was reduced. This correlated with an increase in Ki67 positive cells. Pre-conceptual exposure to sewage sludge reduced small blood vessels in fetal thyroids. Thyroid tissues of exposed fetuses contained regions where mature angio-follicular units were reduced exhibiting decreased immunostaining for sodium-iodide symporter (NIS). Fetal plasma levels of fT3 and fT4 in exposed animals, however, were not different from controls suggesting compensatory changes in the thyroid gland to maintain homeostasis in exposed fetuses. The regional aberrations in thyroid morphology may impact on the post-natal life of the exposed offspring.
    Full-text · Article · Jan 2013 · Molecular and Cellular Endocrinology
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    ABSTRACT: Fetal programming of metabolic diseases is now a well established concept. The scope of the Developmental Origins of Health and Disease has, however, widened and led to the identification of new targets of fetal programming, notably effects on reproductive function. Epidemiologic studies about maternal nutrition and effects on offspring's fertility are rare, but a link between impaired fetal growth, possibly caused by maternal malnutrition, and reproductive function, has been established. The methodologic limitations inherent to human epidemiologic studies can be complemented through the use of animal models, which enable experimental studies on maternal environment and its effect on reproductive functions of the offspring. Altogether, an interaction between inappropriate maternal nutrition (excess or reduced nutritional intake, micronutrient unbalance, or alcohol intake) and reproductive maturation of the offspring has been shown in a majority of experiments as summarized in this review. The exact processes through which maternal nutrition or maternal environment affect reproductive function in the offspring remain unclear but epigenetic modifications are a clear link. Further studies are needed to better understand the mechanisms involved, identify the crucial critical periods, and prevent or treat the adverse effects.
    Full-text · Article · Aug 2012 · Theriogenology
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    ABSTRACT: Knockout of Topaz1 in mice results in male sterility with no post-meiotic spermatids or spermatozoa. Expression of most of genes involved in the PIWI pathway, DNA methylation and retrotransposons silencing will be investigated. The high degree of TOPAZ1 conservation in vertebrates and the presence of its protein in germline stimulate our interest to determine the essential role of Topaz1 in mouse.
    No preview · Article · Apr 2012
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    ABSTRACT: Exposure to ubiquitous, environmental chemicals (ECs) has been hypothesized as a cause for declining male reproductive health. Understanding the long-term effects of EC exposure on reproductive health in humans requires animal models and exposure to real life, environmentally relevant, mixtures during development, a life stage of particular sensitivity to ECs. The aim of this study was to evaluate the effects of in utero and post-natal exposure to environmentally relevant levels of ECs, via sewage sludge application to pasture, on the adult male sheep testis. Hormones, liver concentrations of candidate ECs and Sertoli and germ cell numbers in testes of adult rams that were exposed to ECs in sewage sludge in utero, and until weaning via maternal exposure, and post-weaning via grazing pastures fertilized with sewage sludge, were quantified. Evaluated as a single group, exposure to sludge ECs was without significant effect on most parameters. However, a more detailed study revealed that 5 of 12 sludge-exposed rams exhibited major spermatogenic abnormalities. These consisted of major reductions in germ cell numbers per testis or per Sertoli cell and more Sertoli cell-only tubules, when compared with controls, which did not show any such changes. The sludge-related spermatogenic changes in the five affected animals were significantly different from controls (p < 0.001); Sertoli cell number was unaffected. Hormone profiles and liver candidate EC concentrations were not measurably affected by exposure. We conclude that developmental exposure of male sheep to real-world mixtures of ECs can result in major reduction in germ cell numbers, indicative of impaired sperm production, in a proportion of exposed males. The individual-specific effects are presumed to reflect EC effects on a heterogeneous population in which some individuals may be more susceptible to adverse EC effects. Such effects of EC exposure in humans could have adverse consequences for sperm counts and fertility in some exposed males.
    Full-text · Article · Jan 2012
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    ABSTRACT: Exposure to ubiquitous, environmental chemicals (ECs) has been hypothesized as a cause for declining male reproductive health. Understanding the long-term effects of EC exposure on reproductive health in humans requires animal models and exposure to 'real life', environmentally relevant, mixtures during development, a life stage of particular sensitivity to ECs. The aim of this study was to evaluate the effects of in utero and post-natal exposure to environmentally relevant levels of ECs, via sewage sludge application to pasture, on the adult male sheep testis. Hormones, liver concentrations of candidate ECs and Sertoli and germ cell numbers in testes of adult rams that were exposed to ECs in sewage sludge in utero, and until weaning via maternal exposure, and post-weaning via grazing pastures fertilized with sewage sludge, were quantified. Evaluated as a single group, exposure to sludge ECs was without significant effect on most parameters. However, a more detailed study revealed that 5 of 12 sludge-exposed rams exhibited major spermatogenic abnormalities. These consisted of major reductions in germ cell numbers per testis or per Sertoli cell and more Sertoli cell-only tubules, when compared with controls, which did not show any such changes. The sludge-related spermatogenic changes in the five affected animals were significantly different from controls (p < 0.001); Sertoli cell number was unaffected. Hormone profiles and liver candidate EC concentrations were not measurably affected by exposure. We conclude that developmental exposure of male sheep to real-world mixtures of ECs can result in major reduction in germ cell numbers, indicative of impaired sperm production, in a proportion of exposed males. The individual-specific effects are presumed to reflect EC effects on a heterogeneous population in which some individuals may be more susceptible to adverse EC effects. Such effects of EC exposure in humans could have adverse consequences for sperm counts and fertility in some exposed males.
    Full-text · Article · Dec 2011 · International Journal of Andrology
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    ABSTRACT: We had previously reported that the Suppression Subtractive Hybridization (SSH) approach was relevant for the isolation of new mammalian genes involved in oogenesis and early follicle development. Some of these transcripts might be potential new oocyte and granulosa cell markers. We have now characterized one of them, named TOPAZ1 for the Testis and Ovary-specific PAZ domain gene. Sheep and mouse TOPAZ1 mRNA have 4,803 bp and 4,962 bp open reading frames (20 exons), respectively, and encode putative TOPAZ1 proteins containing 1,600 and 1653 amino acids. They possess PAZ and CCCH domains. In sheep, TOPAZ1 mRNA is preferentially expressed in females during fetal life with a peak during prophase I of meiosis, and in males during adulthood. In the mouse, Topaz1 is a germ cell-specific gene. TOPAZ1 protein is highly conserved in vertebrates and specifically expressed in mouse and sheep gonads. It is localized in the cytoplasm of germ cells from the sheep fetal ovary and mouse adult testis. We have identified a novel PAZ-domain protein that is abundantly expressed in the gonads during germ cell meiosis. The expression pattern of TOPAZ1, and its high degree of conservation, suggests that it may play an important role in germ cell development. Further characterization of TOPAZ1 may elucidate the mechanisms involved in gametogenesis, and particularly in the RNA silencing process in the germ line.
    Full-text · Article · Nov 2011 · PLoS ONE
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    ABSTRACT: This work was supported by the European Community 's Seventh Framework Programme (FP7/2007-2013)
    No preview · Article · Oct 2011
  • Adrienne Baillet · Béatrice Mandon-Pepin
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    ABSTRACT: Over the past 50 years, the ovary development has been subject of fewer studies as compare to the male pathway. Nevertheless due to the advancement of genetics, mouse ES cells and the development of genetic models, studies of ovarian differentiation was boosted. This review emphasizes some of new progresses in the research field of the mammalian ovary differentiation that have occurred in recent years with focuses of the period around prophase I of meiosis and of recent roles of small non-RNAs in the ovarian gene expression.
    No preview · Article · Sep 2011 · Molecular and Cellular Endocrinology
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    ABSTRACT: Successful achievement of early folliculogenesis is crucial for female reproductive function. The process is finely regulated by cell-cell interactions and by the coordinated expression of genes in both the oocyte and in granulosa cells. Despite many studies, little is known about the cell-specific gene expression driving early folliculogenesis. The very small size of these follicles and the mixture of types of follicles within the developing ovary make the experimental study of isolated follicular components very difficult.The recently developed laser capture microdissection (LCM) technique coupled with microarray experiments is a promising way to address the molecular profile of pure cell populations. However, one main challenge was to preserve the RNA quality during the isolation of single cells or groups of cells and also to obtain sufficient amounts of RNA.Using a new LCM method, we describe here the separate expression profiles of oocytes and follicular cells during the first stages of sheep folliculogenesis. We developed a new tissue fixation protocol ensuring efficient single cell capture and RNA integrity during the microdissection procedure. Enrichment in specific cell types was controlled by qRT-PCR analysis of known genes: six oocyte-specific genes (SOHLH2, MAEL, MATER, VASA, GDF9, BMP15) and three granulosa cell-specific genes (KL, GATA4, AMH).A global gene expression profile for each follicular compartment during early developmental stages was identified here for the first time, using a bovine Affymetrix chip. Most notably, the granulosa cell dataset is unique to date. The comparison of oocyte vs. follicular cell transcriptomes revealed 1050 transcripts specific to the granulosa cell and 759 specific to the oocyte.Functional analyses allowed the characterization of the three main cellular events involved in early folliculogenesis and confirmed the relevance and potential of LCM-derived RNA. The ovary is a complex mixture of different cell types. Distinct cell populations need therefore to be analyzed for a better understanding of their potential interactions. LCM and microarray analysis allowed us to identify novel gene expression patterns in follicular cells at different stages and in oocyte populations.
    Full-text · Article · Aug 2011 · BMC Genomics

Publication Stats

662 Citations
104.35 Total Impact Points

Institutions

  • 2002-2013
    • French National Institute for Agricultural Research
      • Biologie du Développement et Reproduction (BDR)
      Lutetia Parisorum, Île-de-France, France
  • 2009
    • Université René Descartes - Paris 5
      Lutetia Parisorum, Île-de-France, France