1
|
Chebrout M, Koné MC, Jan HU, Cournut M, Letheule M, Fleurot R, Aguirre-Lavin T, Peynot N, Jouneau A, Beaujean N, Bonnet-Garnier A. Transcription of rRNA in early mouse embryos promotes chromatin reorganization and expression of major satellite repeats. J Cell Sci 2022; 135:274059. [DOI: 10.1242/jcs.258798] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2021] [Accepted: 01/09/2022] [Indexed: 11/20/2022] Open
Abstract
During the first cell cycles of the early development, the chromatin of the embryo is highly reprogrammed alongside that embryonic genome starts its own transcription. The spatial organization of the genome is a major process that contributes to regulating gene transcription in time and space, however, it is poorly studied in the context of early embryos. To study the cause and effect link between transcription and spatial organization in embryos, we focused on the ribosomal genes, that are first silent and begin to transcribe during the 2-cell stage in the mouse. We demonstrated that ribosomal sequences and early unprocessed rRNAs are spatially organized in a very peculiar manner from the 2-cell to the 16-cell. Using drugs interfering with ribosomal DNA transcription, we show that this organization, totally different from somatic cells, depends on an active transcription of ribosomal genes and induces a unique chromatin environment that favors transcription of major satellite sequences after the 4-cell stage.
Collapse
Affiliation(s)
- Martine Chebrout
- Université Paris-Saclay, UVSQ, INRAE, BREED, 78350, Jouy-en-Josas, France
- Ecole Nationale Vétérinaire d'Alfort, BREED, 94700, Maisons-Alfort, France
| | - Maïmouna Coura Koné
- Université Paris-Saclay, UVSQ, INRAE, BREED, 78350, Jouy-en-Josas, France
- Ecole Nationale Vétérinaire d'Alfort, BREED, 94700, Maisons-Alfort, France
| | - Habib U. Jan
- Université Paris-Saclay, UVSQ, INRAE, BREED, 78350, Jouy-en-Josas, France
- Ecole Nationale Vétérinaire d'Alfort, BREED, 94700, Maisons-Alfort, France
| | - Marie Cournut
- Université Paris-Saclay, UVSQ, INRAE, BREED, 78350, Jouy-en-Josas, France
- Ecole Nationale Vétérinaire d'Alfort, BREED, 94700, Maisons-Alfort, France
| | - Martine Letheule
- Université Paris-Saclay, UVSQ, INRAE, BREED, 78350, Jouy-en-Josas, France
- Ecole Nationale Vétérinaire d'Alfort, BREED, 94700, Maisons-Alfort, France
| | - Renaud Fleurot
- Université Paris-Saclay, UVSQ, INRAE, BREED, 78350, Jouy-en-Josas, France
- Ecole Nationale Vétérinaire d'Alfort, BREED, 94700, Maisons-Alfort, France
| | - Tiphaine Aguirre-Lavin
- Université Paris-Saclay, UVSQ, INRAE, BREED, 78350, Jouy-en-Josas, France
- Ecole Nationale Vétérinaire d'Alfort, BREED, 94700, Maisons-Alfort, France
| | - Nathalie Peynot
- Université Paris-Saclay, UVSQ, INRAE, BREED, 78350, Jouy-en-Josas, France
- Ecole Nationale Vétérinaire d'Alfort, BREED, 94700, Maisons-Alfort, France
| | - Alice Jouneau
- Université Paris-Saclay, UVSQ, INRAE, BREED, 78350, Jouy-en-Josas, France
- Ecole Nationale Vétérinaire d'Alfort, BREED, 94700, Maisons-Alfort, France
| | - Nathalie Beaujean
- Université Paris-Saclay, UVSQ, INRAE, BREED, 78350, Jouy-en-Josas, France
- Ecole Nationale Vétérinaire d'Alfort, BREED, 94700, Maisons-Alfort, France
| | - Amélie Bonnet-Garnier
- Université Paris-Saclay, UVSQ, INRAE, BREED, 78350, Jouy-en-Josas, France
- Ecole Nationale Vétérinaire d'Alfort, BREED, 94700, Maisons-Alfort, France
| |
Collapse
|
2
|
Embryo culture media differentially alter DNA methylating enzymes and global DNA methylation in embryos and oocytes. J Mol Histol 2021; 53:63-74. [PMID: 34741214 PMCID: PMC8570397 DOI: 10.1007/s10735-021-10038-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2021] [Accepted: 10/28/2021] [Indexed: 11/06/2022]
Abstract
The effects of culture media on DNA methylation process, which is one of the epigenetic mechanisms, have not been clearly elucidated although it is known that in vitro culture conditions alter epigenetic mechanisms. This study was designed to address the question: does embryo culture media approach, sequential or single step, differentially affect DNA methylating enzymes and global DNA methylation. Mouse zygotes were cultured either in single step or sequential culture media until the blastocyst stage and in vivo developed blastocyst were utilized as control. Similarly, GV stage oocytes were in vitro matured either in single step or first step of sequential culture media. In vivo matured MII oocytes were used as control. The expression levels and cellular localization of Dnmt1 and 3a enzymes were analyzed by immunofluorescence and western blot analysis while global DNA methylation was evaluated by immunofluorescence. We found that signal intensities of Dnmt1 and Dnmt3a enzymes were significantly low in embryos or oocytes cultured in sequential media compared to single step media and control, which were comparable amongst themself. Similarly, global DNA methylation level in single step media and control groups was comparable but both was higher than the sequential media. This study demonstrated that composition of culture media may differentially affect DNA methylation levels in mouse embryos and oocytes. Since abnormal DNA methylation may cause aberrant oocyte or embryo development, we think that further studies are needed to test human embryos and oocyte, and to explain molecular mechanisms.
Collapse
|
3
|
Tian Y, Sun Y, Ou M, Cui X, Zhou D, Che W. Cloning and expression analysis of GATA1 gene in Carassius auratus red var. BMC Genom Data 2021; 22:12. [PMID: 33736593 PMCID: PMC7977614 DOI: 10.1186/s12863-021-00966-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Accepted: 03/02/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND GATA1 is a key transcription factor in the GATA family, and promotes the differentiation and maturation of red blood cell, which is essential for normal hematopoiesis. RESULTS Our results showed that the cDNA sequence of GATA1 was 2730 bp long encoding 443 amino acids. qRT-PCR analysis demonstrated that GATA1 had the highest expression in testis (T), followed by pituitary (P) and spleen (S). GATA1 gene expression in C. auratus red var. embryo from the neuroblast stage (N) to the embryo hatching (H) changes continuously; and the gene expression levels of nonylphenol (NP)-treated and those of control embryos were significantly different. Moreover, Methylation levels of GATA1 gene in NP-treated embryos were higher than those in control embryos, indicating that NP affected GATA1 methylation. CONCLUSIONS Our study provides cues for further studying the roles of GATA1 gene in fish development, and suggested a potential molecular mechanism by which NP leads to abnormal development of fish embryos.
Collapse
Affiliation(s)
- Yusu Tian
- Hunan Key Laboratory of Economic Crops Genetic Improvement and Integrated Utilization, School of Life Sciences, Hunan University of Science and Technology, Xiangtan, 411201, Hunan, People's Republic of China
| | - Yuandong Sun
- Hunan Key Laboratory of Economic Crops Genetic Improvement and Integrated Utilization, School of Life Sciences, Hunan University of Science and Technology, Xiangtan, 411201, Hunan, People's Republic of China.
| | - Mi Ou
- Key Laboratory of Tropical and Subtropical Fishery Resources Application and Cultivation, Ministry of Agriculture, Pearl River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou, 510380, Guangdong, Hunan, People's Republic of China
| | - Xiaojuan Cui
- Hunan Key Laboratory of Economic Crops Genetic Improvement and Integrated Utilization, School of Life Sciences, Hunan University of Science and Technology, Xiangtan, 411201, Hunan, People's Republic of China
| | - Dinggang Zhou
- Hunan Key Laboratory of Economic Crops Genetic Improvement and Integrated Utilization, School of Life Sciences, Hunan University of Science and Technology, Xiangtan, 411201, Hunan, People's Republic of China
| | - Wen'an Che
- Hunan Key Laboratory of Economic Crops Genetic Improvement and Integrated Utilization, School of Life Sciences, Hunan University of Science and Technology, Xiangtan, 411201, Hunan, People's Republic of China
| |
Collapse
|
4
|
Vrooman LA, Rhon-Calderon EA, Chao OY, Nguyen DK, Narapareddy L, Dahiya AK, Putt ME, Schultz RM, Bartolomei MS. Assisted reproductive technologies induce temporally specific placental defects and the preeclampsia risk marker sFLT1 in mouse. Development 2020; 147:147/11/dev186551. [PMID: 32471820 DOI: 10.1242/dev.186551] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2019] [Accepted: 04/18/2020] [Indexed: 12/11/2022]
Abstract
Although widely used, assisted reproductive technologies (ARTs) are associated with adverse perinatal outcomes. To elucidate their underlying causes, we have conducted a longitudinal analysis of placental development and fetal growth using a mouse model to investigate the effects of individual ART procedures: hormone stimulation, in vitro fertilization (IVF), embryo culture and embryo transfer. We demonstrate that transfer of blastocysts naturally conceived without hormone stimulation and developed in vivo prior to transfer can impair early placentation and fetal growth, but this effect normalizes by term. In contrast, embryos cultured in vitro before transfer do not exhibit this compensation but rather display placental overgrowth, reduced fetal weight, reduced placental DNA methylation and increased levels of sFLT1, an anti-angiogenic protein implicated in causing the maternal symptoms of preeclampsia in humans. Increases in sFLT1 observed in this study suggest that IVF procedures could increase the risk for preeclampsia. Moreover, our results indicate that embryo culture is the major factor contributing to most placental abnormalities and should therefore be targeted for optimization.
Collapse
Affiliation(s)
- Lisa A Vrooman
- Epigenetics Institute, Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Eric A Rhon-Calderon
- Epigenetics Institute, Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Olivia Y Chao
- Epigenetics Institute, Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Duy K Nguyen
- Epigenetics Institute, Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Laren Narapareddy
- Epigenetics Institute, Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA.,Department of Family and Community Health, Claire M. Fagin School of Nursing, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Asha K Dahiya
- Epigenetics Institute, Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Mary E Putt
- Department of Biostatistics, Epidemiology, and Informatics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Richard M Schultz
- Department of Biology, School of Arts and Sciences, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Marisa S Bartolomei
- Epigenetics Institute, Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| |
Collapse
|
5
|
Removing the zona pellucida can decrease cytoplasmic fragmentations in human embryos: a pilot study using 3PN embryos and time-lapse cinematography. J Assist Reprod Genet 2020; 37:1349-1354. [PMID: 32285294 PMCID: PMC7311590 DOI: 10.1007/s10815-020-01773-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Accepted: 04/01/2020] [Indexed: 10/24/2022] Open
Abstract
PURPOSE The aim of this study was to establish a new method of decreasing cytoplasmic fragmentation in early-stage human embryos. METHODS The zona pellucida (ZP) of abnormally-fertilized oocytes (zygotes with three pronuclei (3PN)), which were donated by patients, was removed at the pronuclear stage. ZP-free embryos were observed in a time-lapse imaging and culturing system in order to examine developmental morphology and embryonic quality. RESULTS Based on a modification of Veeck's criteria, 47 of 69 ZP-free 3PN embryos (68.1%) showed fragmentation of less than 20% of the total volume of cytoplasm at the first cleavage (grades 1 and 2), 17 (24.6%) showed 20-40% cytoplasmic fragments (grade 3), and only 5 (7.2%) showed more than 40% fragments (grade 4). These results suggest that the rate of fragmentation is decreased by ZP removal before the first cleavage, compared with normal (ZP-intact) 3PN and 2-pronuclear/2-polar body embryos. CONCLUSIONS This study revealed that the ZP is not always necessary for normal development after the pronuclear stage because the ZP-free embryos studied herein developed normally, maintained their cell adhesion well, and showed a decreased rate of fragmentation. This innovative culture system might provide the major breakthrough needed for patients who have difficulty obtaining good-quality embryos.
Collapse
|
6
|
Mani S, Ghosh J, Coutifaris C, Sapienza C, Mainigi M. Epigenetic changes and assisted reproductive technologies. Epigenetics 2019; 15:12-25. [PMID: 31328632 DOI: 10.1080/15592294.2019.1646572] [Citation(s) in RCA: 62] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Children conceived by Assisted Reproductive Technologies (ART) are at moderately increased risk for a number of undesirable outcomes, including low birth weight. Whether the additional risk is associated with specific procedures used in ART or biological factors that are intrinsic to infertility has been the subject of much debate, as has the mechanism by which ART or infertility might influence this risk. The potential effect of ART clinical and laboratory procedures on the gamete and embryo epigenomes heads the list of mechanistic candidates that might explain the association between ART and undesirable clinical outcomes. The reason for this focus is that the developmental time points at which ART clinical and laboratory procedures are implemented are precisely the time points at which large-scale reorganization of the epigenome takes place during normal development. In this manuscript, we review the many human studies comparing the epigenomes of ART children with children conceived in vivo, as well as assess the potential of individual ART clinical and laboratory procedures to alter the epigenome.
Collapse
Affiliation(s)
- Sneha Mani
- Department of Obstetrics and Gynecology, University of Pennsylvania, Philadelphia, PA, USA
| | - Jayashri Ghosh
- Fels Institute for Cancer Research and Molecular Biology, Temple University, Philadelphia, PA, USA
| | - Christos Coutifaris
- Department of Obstetrics and Gynecology, University of Pennsylvania, Philadelphia, PA, USA
| | - Carmen Sapienza
- Fels Institute for Cancer Research and Molecular Biology, Temple University, Philadelphia, PA, USA
| | - Monica Mainigi
- Department of Obstetrics and Gynecology, University of Pennsylvania, Philadelphia, PA, USA
| |
Collapse
|
7
|
Abstract
This manuscript describes the different topics I have been involved in the fields of reproductive
physiology and embryo biotechnologies with attempts to address practical issues raised
mainly by the breeding industry. The journey started with phenotyping work in the field of
reproductive physio-pathology. Other issues were related to the optimization of reproductive
biotechnologies to favorize genetic selection. The implementation of genomic selection
raised opportunities to develop the use embryo biotechnologies and showed the interest of
combining them in the case of embryo genotyping. There is still a need to refine phenotyping
for reproductive traits especially for the identification of markers of uterine dysfunction.
It is believed that new knowledge generated by combining different molecular approaches
will be the source of applications that may benefit AI practice and embryo technologies.
Collapse
Affiliation(s)
- Patrice Humblot
- Division of Reproduction, Department of Clinical Sciences, SLU, Uppsala, Sweden
| |
Collapse
|
8
|
López-Pelayo I, Gutiérrez-Romero JM, Armada AIM, Calero-Ruiz MM, Acevedo-Yagüe PJMD. Comparison of two commercial embryo culture media (SAGE-1 step single medium vs. G1-PLUSTM/G2-PLUSTM sequential media): Influence on in vitro fertilization outcomes and human embryo quality. JBRA Assist Reprod 2018; 22:128-133. [PMID: 29697926 PMCID: PMC5982559 DOI: 10.5935/1518-0557.20180024] [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: 12/27/2022] Open
Abstract
OBJECTIVE To compare embryo quality, fertilization, implantation, miscarriage and clinical pregnancy rates for embryos cultured in two different commercial culture media until D-2 or D-3. METHODS In this retrospective study, we analyzed 189 cycles performed in 2016. Metaphase II oocytes were microinjected and allocated into single medium (SAGE 1-STEP, Origio) until transferred, frozen or discarded; or, if sequential media were used, the oocytes were cultured in G1-PLUSTM (Vitrolife) up to D-2 or D-3 and in G2-PLUSTM (Vitrolife) to transfer. On the following day, the oocytes were checked for normal fertilization and on D-2 and D-3 for morphological classification. Statistical analysis was performed using the chi-square and Mann-Whitney tests in PASW Statistics 18.0. RESULTS The fertilization rates were 70.07% for single and 69.11% for sequential media (p=0.736). The mean number of embryos with high morphological quality (class A/B) was higher in the single medium than in the sequential media: D-2 [class A (190 vs. 107, p<0.001), B (133 vs. 118, p=0.018)]; D-3 [class A (40 vs. 19, p=0.048) but without differences in class B (40 vs. 49)]. Consequently, a higher number of embryos cultured in single medium were frozen: 197 (21.00%) vs. sequential: 102 (11.00%), p<0.001. No differences were found in implantation rates (30.16% vs. 25.57%, p=0.520), clinical pregnancy rates (55.88% vs. 41.05%, p=0.213), or miscarriage rates (14.29% vs. 9.52%, p=0.472). CONCLUSION Embryo culture in single medium yields greater efficiency per cycle than in sequential media. Higher embryo quality and quantity were achieved, resulting in more frozen embryos. There were no differences in clinical pregnancy rates.
Collapse
Affiliation(s)
- Iratxe López-Pelayo
- Unit for Human Reproduction. UGC Clinical Laboratory. Puerta del Mar University Hospital. Cádiz. Spain
| | | | - Ana Isabel Mangano Armada
- Unit for Human Reproduction. Comprenhensive Care for Woman. Puerta del Mar University Hospital. Cádiz. Spain
| | | | | |
Collapse
|
9
|
Bonnet-Garnier A, Kiêu K, Aguirre-Lavin T, Tar K, Flores P, Liu Z, Peynot N, Chebrout M, Dinnyés A, Duranthon V, Beaujean N. Three-dimensional analysis of nuclear heterochromatin distribution during early development in the rabbit. Chromosoma 2018; 127:387-403. [PMID: 29666907 PMCID: PMC6096579 DOI: 10.1007/s00412-018-0671-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2017] [Revised: 03/06/2018] [Accepted: 04/03/2018] [Indexed: 01/29/2023]
Abstract
Changes to the spatial organization of specific chromatin domains such as constitutive heterochromatin have been studied extensively in somatic cells. During early embryonic development, drastic epigenetic reprogramming of both the maternal and paternal genomes, followed by chromatin remodeling at the time of embryonic genome activation (EGA), have been observed in the mouse. Very few studies have been performed in other mammalian species (human, bovine, or rabbit) and the data are far from complete. During this work, we studied the three-dimensional organization of pericentromeric regions during the preimplantation period in the rabbit using specific techniques (3D-FISH) and tools (semi-automated image analysis). We observed that the pericentromeric regions (identified with specific probes for Rsat I and Rsat II genomic sequences) changed their shapes (from pearl necklaces to clusters), their nuclear localizations (from central to peripheral), as from the 4-cell stage. This reorganization goes along with histone modification changes and reduced amount of interactions with nucleolar precursor body surface. Altogether, our results suggest that the 4-cell stage may be a crucial window for events necessary before major EGA, which occurs during the 8-cell stage in the rabbit.
Collapse
Affiliation(s)
| | - Kiên Kiêu
- UR341 MaIAGE, INRA, Université Paris Saclay, 78350 Jouy-en-Josas, France
| | | | - Krisztina Tar
- Present Address: Department of Medical Chemistry, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
- BioTalentum Ltd., Aulich Lajos str. 26, Gödöllő, 2100 Hungary
| | - Pierre Flores
- UMR BDR, INRA, ENVA, Université Paris Saclay, 78350 Jouy-en-Josas, France
| | - Zichuan Liu
- UMR BDR, INRA, ENVA, Université Paris Saclay, 78350 Jouy-en-Josas, France
- Present Address: Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland
- State Key Laboratory of Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101 China
| | - Nathalie Peynot
- UMR BDR, INRA, ENVA, Université Paris Saclay, 78350 Jouy-en-Josas, France
| | - Martine Chebrout
- UMR BDR, INRA, ENVA, Université Paris Saclay, 78350 Jouy-en-Josas, France
| | - András Dinnyés
- BioTalentum Ltd., Aulich Lajos str. 26, Gödöllő, 2100 Hungary
| | | | - Nathalie Beaujean
- UMR BDR, INRA, ENVA, Université Paris Saclay, 78350 Jouy-en-Josas, France
- Present Address: Univ Lyon, Université Claude Bernard Lyon 1, Inserm, INRA, Stem Cell and Brain Research Institute U1208, USC1361, 69500 Bron, France
| |
Collapse
|
10
|
Duranthon V, Chavatte-Palmer P. Long term effects of ART: What do animals tell us? Mol Reprod Dev 2018; 85:348-368. [DOI: 10.1002/mrd.22970] [Citation(s) in RCA: 52] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2017] [Accepted: 02/09/2018] [Indexed: 01/01/2023]
|
11
|
Canovas S, Ross PJ, Kelsey G, Coy P. DNA Methylation in Embryo Development: Epigenetic Impact of ART (Assisted Reproductive Technologies). Bioessays 2017; 39. [DOI: 10.1002/bies.201700106] [Citation(s) in RCA: 56] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2017] [Revised: 08/14/2017] [Indexed: 12/20/2022]
Affiliation(s)
- Sebastian Canovas
- Physiology of Reproduction Group; University of Murcia; Murcia Spain
- IMIB-Arrixaca Spain; Murcia Spain
| | - Pablo J. Ross
- Department of Animal Science; UC Davis; Davis CA USA
| | - Gavin Kelsey
- Epigenetics Programme; The Babraham Institute; Cambridge UK
| | - Pilar Coy
- Physiology of Reproduction Group; University of Murcia; Murcia Spain
- IMIB-Arrixaca Spain; Murcia Spain
| |
Collapse
|
12
|
Hypo-hydroxymethylation of rRNA genes in the precocious Eriocheir sinensis testes revealed using hMeDIP-seq. Sci Rep 2017; 7:11237. [PMID: 28894189 PMCID: PMC5593943 DOI: 10.1038/s41598-017-11517-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2017] [Accepted: 08/25/2017] [Indexed: 11/30/2022] Open
Abstract
Precocious puberty is a common phenomenon in crab breeding that seriously reduces the economic benefits for crab farmers. To address this problem, this study aimed to explore the potential functions of both methylation and hydroxymethylation of testis rRNA genes with respect to precocious puberty in Eriocheir sinensis. The results showed that the rRNA genes in normally developing testes of E. sinensis had low levels of methylation and high levels of hydroxymethylation; however, although methylation levels were similar, the level of hydroxymethylation in precocious testes was lower than normal. Highly significant differences (P < 0.01) in the hydroxymethylation of the 18S and 28S rRNA genes were found between precocious and normal testes. Our results suggested that both the 18S and 28S rRNA genes, which are normally downregulated by hypo-hydroxymethylation, might be involved in the process of precocious puberty. Our results also implied that hydroxymethylation of the 18S and 28S rRNA genes might be used as an important epigenetic molecular marker to evaluate economically significant potential for growth and breeding in this species.
Collapse
|
13
|
Masala L, Burrai GP, Bellu E, Ariu F, Bogliolo L, Ledda S, Bebbere D. Methylation dynamics during folliculogenesis and early embryo development in sheep. Reproduction 2017; 153:605-619. [PMID: 28250235 DOI: 10.1530/rep-16-0644] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2016] [Revised: 02/10/2017] [Accepted: 02/28/2017] [Indexed: 12/27/2022]
Abstract
Genome-wide DNA methylation reprogramming occurs during mammalian gametogenesis and early embryogenesis. Post-fertilization demethylation of paternal and maternal genomes is considered to occur by an active and passive mechanism respectively, in most mammals but sheep; in this species no loss of methylation was observed in either pronucleus. Post-fertilization reprogramming relies on methylating and demethylating enzymes and co-factors that are stored during oocyte growth, concurrently with the re-methylation of the oocyte itself. The crucial remodelling of the oocyte epigenetic baggage often overlaps with potential interfering events such as exposure to assisted reproduction technologies or environmental changes. Here, we report a temporal analysis of methylation dynamics during folliculogenesis and early embryo development in sheep. We characterized global DNA methylation and hydroxymethylation by immunofluorescence and relatively quantified the expression of the enzymes and co-factors mainly responsible for their remodelling (DNA methyltransferases (DNMTs), ten-eleven translocation (TET) proteins and methyl-CpG-binding domain (MBD) proteins). Our results illustrate for the first time the patterns of hydroxymethylation during oocyte growth. We observed different patterns of methylation and hydroxymethylation between the two parental pronuclei, suggesting that male pronucleus undergoes active demethylation also in sheep. Finally, we describe gene-specific accumulation dynamics for methylating and demethylating enzymes during oocyte growth and observe patterns of expression associated with developmental competence in a differential model of oocyte potential. Our work contributes to the understanding of the methylation dynamics during folliculogenesis and early embryo development and improves the overall picture of early rearrangements that will originate the embryo epigenome.
Collapse
Affiliation(s)
- Laura Masala
- Department of Veterinary MedicineUniversity of Sassari, Sassari, Italy
| | | | - Emanuela Bellu
- Department of Veterinary MedicineUniversity of Sassari, Sassari, Italy
| | - Federica Ariu
- Department of Veterinary MedicineUniversity of Sassari, Sassari, Italy
| | - Luisa Bogliolo
- Department of Veterinary MedicineUniversity of Sassari, Sassari, Italy
| | - Sergio Ledda
- Department of Veterinary MedicineUniversity of Sassari, Sassari, Italy
| | - Daniela Bebbere
- Department of Veterinary MedicineUniversity of Sassari, Sassari, Italy
| |
Collapse
|