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Montgomery T, Uh K, Lee K. TET enzyme driven epigenetic reprogramming in early embryos and its implication on long-term health. Front Cell Dev Biol 2024; 12:1358649. [PMID: 39149518 PMCID: PMC11324557 DOI: 10.3389/fcell.2024.1358649] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2023] [Accepted: 07/23/2024] [Indexed: 08/17/2024] Open
Abstract
Mammalian embryo development is initiated by the union of paternal and maternal gametes. Upon fertilization, their epigenome landscape is transformed through a series of finely orchestrated mechanisms that are crucial for survival and successful embryogenesis. Specifically, maternal or oocyte-specific reprogramming factors modulate germ cell specific epigenetic marks into their embryonic states. Rapid and dynamic changes in epigenetic marks such as DNA methylation and histone modifications are observed during early embryo development. These changes govern the structure of embryonic genome prior to zygotic genome activation. Differential changes in epigenetic marks are observed between paternal and maternal genomes because the structure of the parental genomes allows interaction with specific oocyte reprogramming factors. For instance, the paternal genome is targeted by the TET family of enzymes which oxidize the 5-methylcytosine (5mC) epigenetic mark into 5-hydroxymethylcytosine (5hmC) to lower the level of DNA methylation. The maternal genome is mainly protected from TET3-mediated oxidation by the maternal factor, STELLA. The TET3-mediated DNA demethylation occurs at the global level and is clearly observed in many mammalian species. Other epigenetic modulating enzymes, such as DNA methyltransferases, provide fine tuning of the DNA methylation level by initiating de novo methylation. The mechanisms which initiate the epigenetic reprogramming of gametes are critical for proper activation of embryonic genome and subsequent establishment of pluripotency and normal development. Clinical cases or diseases linked to mutations in reprogramming modulators exist, emphasizing the need to understand mechanistic actions of these modulators. In addition, embryos generated via in vitro embryo production system often present epigenetic abnormalities. Understanding mechanistic actions of the epigenetic modulators will potentially improve the well-being of individuals suffering from these epigenetic disorders and correct epigenetic abnormalities in embryos produced in vitro. This review will summarize the current understanding of epigenetic reprogramming by TET enzymes during early embryogenesis and highlight its clinical relevance and potential implication for assisted reproductive technologies.
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Affiliation(s)
- Ty Montgomery
- Division of Animal Sciences, University of Missouri, Columbia, MO, United States
| | - Kyungjun Uh
- Futuristic Animal Resource and Research Center, Korea Research Institute of Bioscience and Biotechnology, Cheongju-si, Republic of Korea
| | - Kiho Lee
- Division of Animal Sciences, University of Missouri, Columbia, MO, United States
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2
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Xie D, Deng T, Zhai Z, Sun T, Xu Y. The cellular model for Alzheimer's disease research: PC12 cells. Front Mol Neurosci 2023; 15:1016559. [PMID: 36683856 PMCID: PMC9846650 DOI: 10.3389/fnmol.2022.1016559] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2022] [Accepted: 12/08/2022] [Indexed: 01/06/2023] Open
Abstract
Alzheimer's disease (AD) is a common age-related neurodegenerative disease characterized by progressive cognitive decline and irreversible memory impairment. Currently, several studies have failed to fully elucidate AD's cellular and molecular mechanisms. For this purpose, research on related cellular models may propose potential predictive models for the drug development of AD. Therefore, many cells characterized by neuronal properties are widely used to mimic the pathological process of AD, such as PC12, SH-SY5Y, and N2a, especially the PC12 pheochromocytoma cell line. Thus, this review covers the most systematic essay that used PC12 cells to study AD. We depict the cellular source, culture condition, differentiation methods, transfection methods, drugs inducing AD, general approaches (evaluation methods and metrics), and in vitro cellular models used in parallel with PC12 cells.
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Affiliation(s)
- Danni Xie
- State Key Laboratory of Southwestern Chinese Medicine Resources, School of Pharmacy, Chengdu University of Traditional Chinese Medicine, Chengdu, China
| | - Ting Deng
- State Key Laboratory of Southwestern Chinese Medicine Resources, School of Pharmacy, Chengdu University of Traditional Chinese Medicine, Chengdu, China
| | - Zhenwei Zhai
- School of Medical Information Engineering, Chengdu University of Traditional Chinese Medicine, Chengdu, China
| | - Tao Sun
- State Key Laboratory of Southwestern Chinese Medicine Resources, School of Pharmacy, Chengdu University of Traditional Chinese Medicine, Chengdu, China
- School of Medical Information Engineering, Chengdu University of Traditional Chinese Medicine, Chengdu, China
| | - Ying Xu
- TCM Regulating Metabolic Diseases Key Laboratory of Sichuan Province, Hospital of Chengdu University of Traditional Chinese Medicine, Chengdu, China
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3
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Chen PR, Uh K, Redel BK, Reese ED, Prather RS, Lee K. Production of Pigs From Porcine Embryos Generated in vitro. FRONTIERS IN ANIMAL SCIENCE 2022. [DOI: 10.3389/fanim.2022.826324] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Generating porcine embryos in vitro is a critical process for creating genetically modified pigs as agricultural and biomedical models; however, these embryo technologies have been scarcely applied by the swine industry. Currently, the primary issue with in vitro-produced porcine embryos is low pregnancy rate after transfer and small litter size, which may be exasperated by micromanipulation procedures. Thus, in this review, we discuss improvements that have been made to the in vitro porcine embryo production system to increase the number of live piglets per pregnancy as well as abnormalities in the embryos and piglets that may arise from in vitro culture and manipulation techniques. Furthermore, we examine areas related to embryo production and transfer where improvements are warranted that will have direct applications for increasing pregnancy rate after transfer and the number of live born piglets per litter.
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4
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Chen PR, Redel BK, Kerns KC, Spate LD, Prather RS. Challenges and Considerations during In Vitro Production of Porcine Embryos. Cells 2021; 10:cells10102770. [PMID: 34685749 PMCID: PMC8535139 DOI: 10.3390/cells10102770] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2021] [Revised: 10/12/2021] [Accepted: 10/13/2021] [Indexed: 02/02/2023] Open
Abstract
Genetically modified pigs have become valuable tools for generating advances in animal agriculture and human medicine. Importantly, in vitro production and manipulation of embryos is an essential step in the process of creating porcine models. As the in vitro environment is still suboptimal, it is imperative to examine the porcine embryo culture system from several angles to identify methods for improvement. Understanding metabolic characteristics of porcine embryos and considering comparisons with other mammalian species is useful for optimizing culture media formulations. Furthermore, stressors arising from the environment and maternal or paternal factors must be taken into consideration to produce healthy embryos in vitro. In this review, we progress stepwise through in vitro oocyte maturation, fertilization, and embryo culture in pigs to assess the status of current culture systems and address points where improvements can be made.
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Affiliation(s)
- Paula R. Chen
- Division of Animal Sciences, University of Missouri, Columbia, MO 65211, USA
| | | | - Karl C. Kerns
- Department of Animal Science, Iowa State University, Ames, IA 50011, USA
| | - Lee D. Spate
- Division of Animal Sciences, University of Missouri, Columbia, MO 65211, USA
- National Swine Resource and Research Center, University of Missouri, Columbia, MO 65211, USA
| | - Randall S. Prather
- Division of Animal Sciences, University of Missouri, Columbia, MO 65211, USA
- National Swine Resource and Research Center, University of Missouri, Columbia, MO 65211, USA
- Correspondence:
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5
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Zhao X, Nie J, Tang Y, He W, Xiao K, Pang C, Liang X, Lu Y, Zhang M. Generation of Transgenic Cloned Buffalo Embryos Harboring the EGFP Gene in the Y Chromosome Using CRISPR/Cas9-Mediated Targeted Integration. Front Vet Sci 2020; 7:199. [PMID: 32426378 PMCID: PMC7212351 DOI: 10.3389/fvets.2020.00199] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2020] [Accepted: 03/25/2020] [Indexed: 11/16/2022] Open
Abstract
Sex control technology is of great significance in the production of domestic animals, especially for rapidly breeding water buffalo (bubalus bubalis), which served as a research model in the present study. We have confirmed that a fluorescence protein integrated into the Y chromosome is fit for sexing pre-implantation embryos in the mouse. Firstly, we optimized the efficiency of targeted integration of exogenous gene encoding enhanced green fluorescent protein (eGFP) and mCherry in Neuro-2a cells, mouse embryonic stem cells, mouse embryonic cells (NIH3T3), buffalo fetal fibroblast (BFF) cells. The results showed that a homology arm length of 800 bp on both sides of the target is more efficient that 300 bp or 300 bp/800 bp. Homology-directed repair (HDR)-mediated knock-in in BFF cells was also significantly improved when cells were supplemented with pifithrin-μ, which is a small molecule that inhibits the binding of p53 to mitochondria. Three pulses at 250 V resulted in the most efficient electroporation in BFF cells and 1.5 μg/mL puromycin was found to be the optimal concentration for screening. Moreover, Y-Chr-eGFP transgenic BFF cells and cloned buffalo embryos were successfully generated using CRISPR/Cas9-mediated gene editing combined with the somatic cell nuclear transfer (SCNT) technique. At passage numbers 6–8, the growth rate and cell proliferation rate were significantly lower in Y-Chr-eGFP transgenic than in non-transgenic BFF cells; the expression levels of the methylation-related genes DNMT1 and DNMT3a were similar; however, the expression levels of the acetylation-related genes HDAC1, HDAC2, and HDAC3 were significantly higher (p < 0.05) in Y-Chr-eGFP transgenic BFF cells compared with non-transgenic cells. Y-Chr-eGFP transgenic BFFs were used as donors for SCNT, the results showed that eGFP reporter is suitable for the visualization of the sex of embryos. The blastocyst rates of cloned buffalo embryos were similar; however, the cleavage rates of transgenic cloned embryos were significantly lower compared with control. In summary, we optimized the protocol for generating transgenic BFF cells and successfully generated Y-Chr-eGFP transgenic embryos using these cells as donors.
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Affiliation(s)
- Xiuling Zhao
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, Animal Reproduction Institute, Guangxi University, Nanning, China
| | - Junyu Nie
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, Animal Reproduction Institute, Guangxi University, Nanning, China
| | - Yuyan Tang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, Animal Reproduction Institute, Guangxi University, Nanning, China
| | - Wengtan He
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, Animal Reproduction Institute, Guangxi University, Nanning, China
| | - Kai Xiao
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, Animal Reproduction Institute, Guangxi University, Nanning, China
| | - Chunying Pang
- Key Laboratory of Buffalo Genetics, Breeding and Reproduction Technology, Ministry of Agriculture and Buffalo Research Institute, Chinese Academy of Agricultural Science, Nanning, China
| | - Xianwei Liang
- Key Laboratory of Buffalo Genetics, Breeding and Reproduction Technology, Ministry of Agriculture and Buffalo Research Institute, Chinese Academy of Agricultural Science, Nanning, China
| | - Yangqing Lu
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, Animal Reproduction Institute, Guangxi University, Nanning, China
| | - Ming Zhang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, Animal Reproduction Institute, Guangxi University, Nanning, China
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6
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Mordhorst BR, Murphy SL, Schauflinger M, Rojas Salazar S, Ji T, Behura SK, Wells KD, Green JA, Prather RS. Porcine Fetal-Derived Fibroblasts Alter Gene Expression and Mitochondria to Compensate for Hypoxic Stress During Culture. Cell Reprogram 2019; 20:225-235. [PMID: 30089028 PMCID: PMC6088251 DOI: 10.1089/cell.2018.0008] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
The Warburg effect is characterized by decreased mitochondrial oxidative phosphorylation and increased glycolytic flux in adequate oxygen. The preimplantation embryo has been described to have characteristics of the Warburg effect, including similar changes in gene expression and mitochondria, which are more rudimentary in appearance. We hypothesized hypoxia would facilitate anaerobic glycolysis in fibroblasts thereby promoting gene expression and media metabolite production reflecting the Warburg effect hallmarks in early embryos. Additionally, we speculated that hypoxia would induce a rudimentary small mitochondrial phenotype observed in several cell types evidenced to demonstrate the Warburg effect. While many have examined the role hypoxia plays in pathological conditions, few studies have investigated changes in primary cells which could be used in somatic cell nuclear transfer. We found that cells grown in 1.25% O2 had normal cell viability and more, but smaller mitochondria. Several hypoxia-inducible genes were identified, including seven genes for glycolytic enzymes. In conditioned media from hypoxic cells, the quantities of gluconolactone, cytosine, and uric acid were decreased indicating higher consumption than control cells. These results indicate that fibroblasts alter gene expression and mitochondria to compensate for hypoxic stress and maintain viability. Furthermore, the metabolic changes observed, making them more similar to preimplantation embryos, could be facilitating nuclear reprogramming making these cells more amendable to future use in somatic cell nuclear transfer.
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Affiliation(s)
- Bethany R Mordhorst
- 1 Department of Animal Sciences, University of Missouri , Columbia, Missouri
| | - Stephanie L Murphy
- 1 Department of Animal Sciences, University of Missouri , Columbia, Missouri
| | - Martin Schauflinger
- 2 Electron Microscopy Core Facility, University of Missouri , Columbia, Missouri
| | | | - Tieming Ji
- 3 Department of Statistics, University of Missouri , Columbia, Missouri
| | - Susanta K Behura
- 1 Department of Animal Sciences, University of Missouri , Columbia, Missouri
| | - Kevin D Wells
- 1 Department of Animal Sciences, University of Missouri , Columbia, Missouri
| | - Jonathan A Green
- 1 Department of Animal Sciences, University of Missouri , Columbia, Missouri
| | - Randall S Prather
- 1 Department of Animal Sciences, University of Missouri , Columbia, Missouri
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7
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He X, Tan C, Li Z, Zhao C, Shi J, Zhou R, Wang X, Jiang G, Cai G, Liu D, Wu Z. Characterization and comparative analyses of transcriptomes of cloned and in vivo fertilized porcine pre-implantation embryos. Biol Open 2019; 8:bio.039917. [PMID: 30952695 PMCID: PMC6504007 DOI: 10.1242/bio.039917] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Somatic cell nuclear transfer (SCNT) is the only method known to rapidly reprogram differentiated cells into totipotent embryos. Most cloned embryos become arrested before implantation and the details of the underlying molecular mechanism remain largely unknown. Dynamic regulation of the transcriptome is a key molecular mechanism driving early embryonic development. Here, we report comprehensive transcriptomic analysis of cloned embryos (from Laiwu and Duroc pigs) and in vivo fertilized embryos (from Duroc pigs) using RNA-sequencing. Comparisons between gene expression patterns were performed according to differentially expressed genes, specific-expressed genes, first-expressed genes, pluripotency genes and pathway enrichment analysis. In addition, we closely analyzed the improperly expressed histone lysine methyltransferases and histone lysine demethylases during cell reprogramming in cloned embryos. In summary, we identified altered gene expression profiles in porcine cloned pre-implantation embryos in comparison to normal in vivo embryos. Our findings provide a substantial framework for further discovery of the epigenetic reprogramming mechanisms in porcine SCNT embryos. Summary: Comparative transcriptome analyses of cloned and in vivo fertilized pre-implantation embryos: transcriptional defects and reprogramming barriers in porcine somatic cell nuclear reprogramming.
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Affiliation(s)
- Xiaoyan He
- National Engineering Research Center for Breeding Swine Industry, College of Animal Science, South China Agricultural University, Guangzhou 510642, China.,Wen's Group Academy, Wen's Foodstuff Group Co., Ltd, Yunfu 527400, China, China
| | - Cheng Tan
- National Engineering Research Center for Breeding Swine Industry, College of Animal Science, South China Agricultural University, Guangzhou 510642, China.,Wen's Group Academy, Wen's Foodstuff Group Co., Ltd, Yunfu 527400, China, China
| | - Zicong Li
- National Engineering Research Center for Breeding Swine Industry, College of Animal Science, South China Agricultural University, Guangzhou 510642, China
| | - Chengfa Zhao
- National Engineering Research Center for Breeding Swine Industry, College of Animal Science, South China Agricultural University, Guangzhou 510642, China
| | - Junsong Shi
- Wen's Group Academy, Wen's Foodstuff Group Co., Ltd, Yunfu 527400, China, China
| | - Rong Zhou
- Wen's Group Academy, Wen's Foodstuff Group Co., Ltd, Yunfu 527400, China, China
| | - Xingwang Wang
- National Engineering Research Center for Breeding Swine Industry, College of Animal Science, South China Agricultural University, Guangzhou 510642, China
| | - Gelong Jiang
- Wen's Group Academy, Wen's Foodstuff Group Co., Ltd, Yunfu 527400, China, China
| | - Gengyuan Cai
- National Engineering Research Center for Breeding Swine Industry, College of Animal Science, South China Agricultural University, Guangzhou 510642, China
| | - Dewu Liu
- National Engineering Research Center for Breeding Swine Industry, College of Animal Science, South China Agricultural University, Guangzhou 510642, China
| | - Zhenfang Wu
- National Engineering Research Center for Breeding Swine Industry, College of Animal Science, South China Agricultural University, Guangzhou 510642, China
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8
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Mordhorst BR, Benne JA, Cecil RF, Whitworth KM, Samuel MS, Spate LD, Murphy CN, Wells KD, Green JA, Prather RS. Improvement of in vitro and early in utero porcine clone development after somatic donor cells are cultured under hypoxia. Mol Reprod Dev 2019; 86:558-565. [PMID: 30779254 PMCID: PMC6510642 DOI: 10.1002/mrd.23132] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2018] [Revised: 01/06/2019] [Accepted: 01/28/2019] [Indexed: 12/25/2022]
Abstract
Genetically engineered pigs serve as excellent biomedical and agricultural models. To date, the most reliable way to generate genetically engineered pigs is via somatic cell nuclear transfer (SCNT), however, the efficiency of cloning in pigs is low (1-3%). Somatic cells such as fibroblasts frequently used in nuclear transfer utilize the tricarboxylic acid cycle and mitochondrial oxidative phosphorylation for efficient energy production. The metabolism of somatic cells contrasts with cells within the early embryo, which predominately use glycolysis. We hypothesized that fibroblast cells could become blastomere-like if mitochondrial oxidative phosphorylation was inhibited by hypoxia and that this would result in improved in vitro embryonic development after SCNT. In a previous study, we demonstrated that fibroblasts cultured under hypoxic conditions had changes in gene expression consistent with increased glycolytic/gluconeogenic metabolism. The goal of this pilot study was to determine if subsequent in vitro embryo development is impacted by cloning porcine embryonic fibroblasts cultured in hypoxia. Here we demonstrate that in vitro measures such as early cleavage, blastocyst development, and blastocyst cell number are improved (4.4%, 5.5%, and 17.6 cells, respectively) when donor cells are cultured in hypoxia before nuclear transfer. Survival probability was increased in clones from hypoxic cultured donors compared to controls (8.5 vs. 4.0 ± 0.2). These results suggest that the clones from donor cells cultured in hypoxia are more developmentally competent and this may be due to improved nuclear reprogramming during somatic cell nuclear transfer.
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Affiliation(s)
| | - Joshua A Benne
- Department of Animal Sciences, University of Missouri, Columbia, Missouri
| | - Raissa F Cecil
- Department of Animal Sciences, University of Missouri, Columbia, Missouri
| | | | - Melissa S Samuel
- Department of Animal Sciences, University of Missouri, Columbia, Missouri
| | - Lee D Spate
- Department of Animal Sciences, University of Missouri, Columbia, Missouri
| | - Clifton N Murphy
- Department of Animal Sciences, University of Missouri, Columbia, Missouri
| | - Kevin D Wells
- Department of Animal Sciences, University of Missouri, Columbia, Missouri
| | - Jonathan A Green
- Department of Animal Sciences, University of Missouri, Columbia, Missouri
| | - Randall S Prather
- Department of Animal Sciences, University of Missouri, Columbia, Missouri
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9
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Can Reprogramming of Overall Epigenetic Memory and Specific Parental Genomic Imprinting Memory within Donor Cell-Inherited Nuclear Genome be a Major Hindrance for the Somatic Cell Cloning of Mammals? – A Review. ANNALS OF ANIMAL SCIENCE 2018. [DOI: 10.2478/aoas-2018-0015] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Abstract
Successful cloning of animals by somatic cell nuclear transfer (SCNT) requires epigenetic transcriptional reprogramming of the differentiated state of the donor cell nucleus to a totipotent embryonic ground state. It means that the donor nuclei must cease its own program of gene expression and restore a particular program of the embryonic genome expression regulation that is necessary for normal development. Transcriptional activity of somatic cell-derived nuclear genome during embryo pre- and postimplantation development as well as foetogenesis is correlated with the frequencies for spatial remodeling of chromatin architecture and reprogramming of cellular epigenetic memory. This former and this latter process include such covalent modifications as demethylation/re-methylation of DNA cytosine residues and acetylation/deacetylation as well as demethylation/re-methylation of lysine residues of nucleosomal core-derived histones H3 and H4. The main cause of low SCNT efficiency in mammals turns out to be an incomplete reprogramming of transcriptional activity for donor cell-descended genes. It has been ascertained that somatic cell nuclei should undergo the wide DNA cytosine residue demethylation changes throughout the early development of cloned embryos to reset their own overall epigenetic and parental genomic imprinting memories that have been established by re-methylation of the nuclear donor cell-inherited genome during specific pathways of somatic and germ cell lineage differentiation. A more extensive understanding of the molecular mechanisms and recognition of determinants for epigenetic transcriptional reprogrammability of somatic cell nuclear genome will be helpful to solve the problems resulting from unsatisfactory SCNT effectiveness and open new possibilities for common application of this technology in transgenic research focused on human biomedicine.
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10
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Mordhorst BR, Murphy SL, Ross RM, Benne JA, Samuel MS, Cecil RF, Redel BK, Spate LD, Murphy CN, Wells KD, Green JA, Prather RS. Pharmacologic treatment of donor cells induced to have a Warburg effect-like metabolism does not alter embryonic development in vitro or survival during early gestation when used in somatic cell nuclear transfer in pigs. Mol Reprod Dev 2018; 85:290-302. [PMID: 29392839 DOI: 10.1002/mrd.22964] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2017] [Revised: 01/14/2018] [Accepted: 01/17/2018] [Indexed: 11/08/2022]
Abstract
Somatic cell nuclear transfer is a valuable technique for the generation of genetically engineered animals, however, the efficiency of cloning in mammalian species is low (1-3%). Differentiated somatic cells commonly used in nuclear transfer utilize the tricarboxylic acid cycle and cellular respiration for energy production. Comparatively the metabolism of somatic cells contrasts that of the cells within the early embryos which predominately use glycolysis. Early embryos (prior to implantation) are evidenced to exhibit characteristics of a Warburg Effect (WE)-like metabolism. We hypothesized that pharmacologically driven fibroblast cells can become more blastomere-like and result in improved in vitro embryonic development after SCNT. The goals were to determine if subsequent in vitro embryo development is impacted by (1) cloning pharmacologically treated donor cells pushed to have a WE-like metabolism or (2) culturing non-treated donor clones with pharmaceuticals used to push a WE-like metabolism. Additionally, we investigated early gestational survival of the donor-treated clone embryos. Here we demonstrate that in vitro development of clones is not hindered by pharmacologically treating either the donor cells or the embryos themselves with CPI, PS48, or the combination of these drugs. Furthermore, these experiments demonstrate that early embryos (or at least in vitro produced embryos) have a low proportion of mitochondria which have high membrane potential and treatment with these pharmaceuticals does not further alter the mitochondrial function in early embryos. Lastly, we show that survival in early gestation was not different between clones from pharmacologically induced WE-like donor cells and controls.
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Affiliation(s)
| | | | - Renee M Ross
- Division of Animal Sciences, University of Missouri, Columbia, Missouri
| | - Joshua A Benne
- Division of Animal Sciences, University of Missouri, Columbia, Missouri
| | - Melissa S Samuel
- Division of Animal Sciences, University of Missouri, Columbia, Missouri
| | - Raissa F Cecil
- Division of Animal Sciences, University of Missouri, Columbia, Missouri
| | - Bethany K Redel
- Division of Animal Sciences, University of Missouri, Columbia, Missouri
| | - Lee D Spate
- Division of Animal Sciences, University of Missouri, Columbia, Missouri
| | - Clifton N Murphy
- Division of Animal Sciences, University of Missouri, Columbia, Missouri
| | - Kevin D Wells
- Division of Animal Sciences, University of Missouri, Columbia, Missouri
| | - Jonathan A Green
- Division of Animal Sciences, University of Missouri, Columbia, Missouri
| | - Randall S Prather
- Division of Animal Sciences, University of Missouri, Columbia, Missouri
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11
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Huan Y, Hu K, Xie B, Shi Y, Wang F, Zhou Y, Liu S, Huang B, Zhu J, Liu Z, He Y, Li J, Kong Q, Liu Z. Ovulation Statuses of Surrogate Gilts Are Associated with the Efficiency of Excellent Pig Cloning. PLoS One 2015; 10:e0142549. [PMID: 26565717 PMCID: PMC4643933 DOI: 10.1371/journal.pone.0142549] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2015] [Accepted: 10/25/2015] [Indexed: 11/18/2022] Open
Abstract
Somatic cell nuclear transfer (SCNT) is an assisted reproductive technique that can produce multiple copies of excellent livestock. However, low cloning efficiency limits the application of SCNT. In this study, we systematically investigated the major influencing factors related to the overall cloning efficiency in pigs. Here, 13620 cloned embryos derived from excellent pigs were transferred into 79 surrogate gilts, and 119 live cloned piglets were eventually generated. During cloning, group of cloned embryos derived from excellent Landrace or Large white pigs presented no significant differences of cleavage and blastocyst rates, blastocyst cell numbers, surrogate pregnancy and delivery rates, average numbers of piglets born and alive and cloning efficiencies, and group of 101-150, 151-200 or 201-250 cloned embryos transferred per surrogate also displayed a similar developmental efficiency. When estrus stage of surrogate gilts was compared, group of embryo transfer on Day 2 of estrus showed significantly higher pregnancy rate, delivery rate, average number of piglets born, average alive piglet number or cloning efficiency than group on Day 1, Day 3, Day 4 or Day 5, respectively (P<0.05). And, in comparison with the preovulation and postovulation groups, group of surrogate gilts during periovulation displayed a significantly higher overall cloning efficiency (P<0.05). Further investigation of surrogate estrus stage and ovulation status displayed that ovulation status was the real factor underlying estrus stage to determine the overall cloning efficiency. And more, follicle puncture for preovulation, not transfer position shallowed for preovulation or deepened for postovulation, significantly improved the average number of piglets alive and cloning efficiency (P<0.05). In conclusion, our results demonstrated that ovulation status of surrogate gilts was the fundamental factor determining the overall cloning efficiency of excellent pigs, and follicle puncture, not transfer position change, improved cloning efficiency. This work would have important implications in preserving and breeding excellent livestock and improving the overall cloning efficiency.
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Affiliation(s)
- Yanjun Huan
- College of Life Science, Northeast Agricultural University, Harbin, Heilongjiang Province, China
| | - Kui Hu
- College of Life Science, Northeast Agricultural University, Harbin, Heilongjiang Province, China
| | - Bingteng Xie
- College of Life Science, Northeast Agricultural University, Harbin, Heilongjiang Province, China
| | - Yongqian Shi
- College of Life Science, Northeast Agricultural University, Harbin, Heilongjiang Province, China
| | - Feng Wang
- College of Life Science, Northeast Agricultural University, Harbin, Heilongjiang Province, China
| | - Yang Zhou
- College of Life Science, Northeast Agricultural University, Harbin, Heilongjiang Province, China
| | - Shichao Liu
- College of Life Science, Northeast Agricultural University, Harbin, Heilongjiang Province, China
| | - Bo Huang
- College of Life Science, Northeast Agricultural University, Harbin, Heilongjiang Province, China
| | - Jiang Zhu
- College of Life Science, Northeast Agricultural University, Harbin, Heilongjiang Province, China
| | - Zhongfeng Liu
- College of Life Science, Northeast Agricultural University, Harbin, Heilongjiang Province, China
| | - Yilong He
- College of Life Science, Northeast Agricultural University, Harbin, Heilongjiang Province, China
| | - Jingyu Li
- College of Life Science, Northeast Agricultural University, Harbin, Heilongjiang Province, China
| | - Qingran Kong
- College of Life Science, Northeast Agricultural University, Harbin, Heilongjiang Province, China
| | - Zhonghua Liu
- College of Life Science, Northeast Agricultural University, Harbin, Heilongjiang Province, China
- * E-mail:
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12
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Huan YJ, Wu ZF, Zhang JG, Zhu J, Xie BT, Wang JY, Li JY, Xue BH, Kong QR, Liu ZH. Alteration of the DNA methylation status of donor cells impairs the developmental competence of porcine cloned embryos. J Reprod Dev 2015; 62:71-7. [PMID: 26537205 PMCID: PMC4768780 DOI: 10.1262/jrd.2015-048] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Nuclear reprogramming induced by somatic cell nuclear transfer is an inefficient process, and donor cell DNA
methylation status is thought to be a major factor affecting cloning efficiency. Here, the role of donor cell
DNA methylation status regulated by 5-aza-2'-deoxycytidine (5-aza-dC) or
5-methyl-2'-deoxycytidine-5'-triphosphate (5-methyl-dCTP) in the early development of porcine cloned embryos
was investigated. Our results showed that 5-aza-dC or 5-methyl-dCTP significantly reduced or increased the
global methylation levels and altered the methylation and expression levels of key genes in donor cells.
However, the development of cloned embryos derived from these cells was reduced. Furthermore, disrupted
pseudo-pronucleus formation and transcripts of early embryo development-related genes were observed in cloned
embryos derived from these cells. In conclusion, our results demonstrated that alteration of the DNA
methylation status of donor cells by 5-aza-dC or 5-methyl-dCTP disrupted nuclear reprogramming and impaired
the developmental competence of porcine cloned embryos.
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Affiliation(s)
- Yan Jun Huan
- College of Life Science, Northeast Agricultural University, Harbin 150030, China
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13
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Trichostatin A-mediated epigenetic transformation of adult bone marrow-derived mesenchymal stem cells biases the in vitro developmental capability, quality, and pluripotency extent of porcine cloned embryos. BIOMED RESEARCH INTERNATIONAL 2015; 2015:814686. [PMID: 25866813 PMCID: PMC4381569 DOI: 10.1155/2015/814686] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/01/2014] [Accepted: 02/21/2015] [Indexed: 12/23/2022]
Abstract
The current research was conducted to explore the in vitro developmental outcome and cytological/molecular quality of porcine nuclear-transferred (NT) embryos reconstituted with adult bone marrow-derived mesenchymal stem cells (ABM-MSCs) that were epigenetically transformed by treatment with nonspecific inhibitor of histone deacetylases, known as trichostatin A (TSA). The cytological quality of cloned blastocysts was assessed by estimation of the total cells number (TCN) and apoptotic index. Their molecular quality was evaluated by real-time PCR-mediated quantification of gene transcripts for pluripotency- and multipotent stemness-related markers (Oct4, Nanog, and Nestin). The morula and blastocyst formation rates of NT embryos derived from ABM-MSCs undergoing TSA treatment were significantly higher than in the TSA-unexposed group. Moreover, the NT blastocysts generated using TSA-treated ABM-MSCs exhibited significantly higher TCN and increased pluripotency extent measured with relative abundance of Oct4 and Nanog mRNAs as compared to the TSA-untreated group. Altogether, the improvements in morula/blastocyst yields and quality of cloned pig embryos seem to arise from enhanced abilities for promotion of correct epigenetic reprogramming of TSA-exposed ABM-MSC nuclei in a cytoplasm of reconstructed oocytes. To our knowledge, we are the first to report the successful production of mammalian high-quality NT blastocysts using TSA-dependent epigenomic modulation of ABM-MSCs.
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14
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Prather RS, Redel BK, Whitworth KM, Zhao MT. Genomic profiling to improve embryogenesis in the pig. Anim Reprod Sci 2014; 149:39-45. [PMID: 24878355 DOI: 10.1016/j.anireprosci.2014.04.017] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2014] [Revised: 04/16/2014] [Accepted: 04/21/2014] [Indexed: 01/01/2023]
Abstract
Over the past decade the technology to characterize transcription during embryogenesis has progressed from estimating a single transcript to a reliable description of the entire transcriptome. Northern blots were followed by sequencing ESTs, quantitative real time PCR, cDNA arrays, custom oligo arrays, and more recently, deep sequencing. The amount of information that can be generated is overwhelming. The challenge now is how to glean information from these vast data sets that can be used to understand development and to improve methods for creating and culturing embryos in vitro, and for reducing reproductive loss. The use of ESTs permitted the identification of SPP1 as an oviductal component that could reduce polyspermy. Microarrays identified LDL and NMDA as components to replace BSA in embryo culture media. Deep sequencing implicated arginine, glycine, and folate as components that should be adjusted in our current culture system, and identified a characteristic of embryo metabolism that is similar to cancer and stem cells. Not only will these characterizations aid in improving in vitro production of embryos, but will also be useful for identifying, or creating conditions for donor cells that will be more likely to result in normal development of cloned embryos. The easily found targets have been identified, and now more sophisticated methods are being employed to advance our understanding of embryogenesis. Here the technology to study the global transcriptome is reviewed followed by specific examples of how the technology has been used to understand and improve porcine embryogenesis both in vitro and in vivo.
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Affiliation(s)
- Randall S Prather
- Division of Animal Science, University of Missouri, Columbia, MO, USA.
| | - Bethany K Redel
- Division of Animal Science, University of Missouri, Columbia, MO, USA
| | | | - Ming-Tao Zhao
- Division of Animal Science, University of Missouri, Columbia, MO, USA
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15
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Xie B, Wang J, Liu S, Wang J, Xue B, Li J, Wei R, Zhao Y, Liu Z. Positive correlation between the efficiency of induced pluripotent stem cells and the development rate of nuclear transfer embryos when the same porcine embryonic fibroblast lines are used as donor cells. Cell Reprogram 2014; 16:206-14. [PMID: 24738969 DOI: 10.1089/cell.2013.0080] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Induced pluripotent stem cells (iPSCs) and nuclear transfer (NT) are two of the primary routes to reprogram differentiated cells back to the pluripotent state. However, it is still unknown whether there is any correlation between the reprogramming efficiency of iPSCs and NT if the same donor cells are employed. In this study, six porcine embryonic fibroblast (PEF) lines from Landrace (L1, L6, L9) or Congjiang local pigs (C4, C5, C6) were used for iPSC induction and NT. Furthermore, the resultant iPSCs from four PEF lines (L1, L6, C4, and C5) were used for NT (iPSC-NT), and the expression of exogenous genes was detected in iPSC-NT embryos by real-time PCR. The results showed that the efficiency of iPSC lines established from different PEF lines were significantly different. When the same PEF lines were used as donor cells for NT, the blastocysts rates were also different among different PEF lines and positively related with iPSCs induction efficiency. When the iPSCs were used as donor cells for NT, compared with the source PEFs, the blastocysts rates were significantly decreased. Real-time PCR results indicated that exogenous genes (Oct4, c-Myc) continued to be expressed in iPSC-NT embryos. In summary, our results demonstrate that there was a positive correlation between iPSCs and NT reprogramming efficiency, although the mechanism of these two routes is different. This may provide a new method to select the appropriate donor cells for inducing iPSCs.
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Affiliation(s)
- Bingteng Xie
- 1 College of Life Science, Northeast Agricultural University of China , Harbin, 150030, China
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16
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Bordignon V, El-Beirouthi N, Gasperin BG, Albornoz MS, Martinez-Diaz MA, Schneider C, Laurin D, Zadworny D, Agellon LB. Production of cloned pigs with targeted attenuation of gene expression. PLoS One 2013; 8:e64613. [PMID: 23737990 PMCID: PMC3667777 DOI: 10.1371/journal.pone.0064613] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2012] [Accepted: 04/16/2013] [Indexed: 12/20/2022] Open
Abstract
The objective of this study was to demonstrate that RNA interference (RNAi) and somatic cell nuclear transfer (SCNT) technologies can be used to attenuate the expression of specific genes in tissues of swine, a large animal species. Apolipoprotein E (apoE), a secreted glycoprotein known for its major role in lipid and lipoprotein metabolism and transport, was selected as the target gene for this study. Three synthetic small interfering RNAs (siRNA) targeting the porcine apoE mRNA were tested in porcine granulosa cells in primary culture and reduced apoE mRNA abundance ranging from 45-82% compared to control cells. The most effective sequence was selected for cloning into a short hairpin RNA (shRNA) expression vector under the control of RNA polymerase III (U6) promoter. Stably transfected fetal porcine fibroblast cells were generated and used to produce embryos with in vitro matured porcine oocytes, which were then transferred into the uterus of surrogate gilts. Seven live and one stillborn piglet were born from three gilts that became pregnant. Integration of the shRNA expression vector into the genome of clone piglets was confirmed by PCR and expression of the GFP transgene linked to the expression vector. Analysis showed that apoE protein levels in the liver and plasma of the clone pigs bearing the shRNA expression vector targeting the apoE mRNA was significantly reduced compared to control pigs cloned from non-transfected fibroblasts of the same cell line. These results demonstrate the feasibility of applying RNAi and SCNT technologies for introducing stable genetic modifications in somatic cells for eventual attenuation of gene expression in vivo in large animal species.
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Affiliation(s)
| | | | | | | | | | | | - Denyse Laurin
- Department of Animal Science, McGill University, Quebec, Canada
| | - David Zadworny
- Department of Animal Science, McGill University, Quebec, Canada
| | - Luis B. Agellon
- School of Dietetics and Human Nutrition, McGill University, Quebec, Canada
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17
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Hua S, Lu C, Song Y, Li R, Liu X, Quan F, Wang Y, Liu J, Su F, Zhang Y. High levels of mitochondrial heteroplasmy modify the development of ovine-bovine interspecies nuclear transferred embryos. Reprod Fertil Dev 2012; 24:501-9. [PMID: 22401282 DOI: 10.1071/rd11091] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2011] [Accepted: 09/03/2011] [Indexed: 01/09/2023] Open
Abstract
To investigate the effect of mitochondrial heteroplasmy on embryo development, cloned embryos produced using bovine oocytes as the recipient cytoplasm and ovine granulosa cells as the donor nuclei were complemented with 2pL mitochondrial suspension isolated from ovine (BOOMT embryos) or bovine (BOBMT embryos) granulosa cells; cloned embryos without mitochondrial injection served as the control group (BO embryos). Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and sodium bisulfite genomic sequencing were used to analyse mRNA and methylation levels of pluripotency genes (OCT4, SOX2) and mitochondrial genes (TFAM, POLRMT) in the early developmental stages of cloned embryos. The number of mitochondrial DNA copies in 2pL ovine-derived and bovine-derived mitochondrial suspensions was 960±110 and 1000±120, respectively. The blastocyst formation rates were similar in BOBMT and BO embryos (P>0.05), but significantly higher than in BOOMT embryos (P<0.01). Expression of OCT4 and SOX2, as detected by RT-qPCR, decreased significantly in BOOMT embryos (P<0.05), whereas the expression of TFAM and POLRMT increased significantly, compared with expression in BOOMT and BO embryos (P<0.05). In addition, methylation levels of OCT4 and SOX2 were significantly greater (P<0.05), whereas those of TFAM and POLRMT were significantly lower (P<0.01), in BOOMT embryos compared with BOBMT and BO embryos. Together, the results of the present study suggest that the degree of mitochondrial heteroplasmy may affect embryonic development.
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Affiliation(s)
- Song Hua
- College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi Province 712100, People's Republic of China.
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18
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Himaki T, Mizobe Y, Tsuda K, Suetomo M, Yamakuchi H, Miyoshi K, Takao S, Yoshida M. Effect of postactivation treatment with latrunculin A on in vitro and in vivo development of cloned embryos derived from kidney fibroblasts of an aged Clawn miniature boar. J Reprod Dev 2012; 58:398-403. [PMID: 22498812 DOI: 10.1262/jrd.11-083a] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The objective of this study was to examine the effect of postactivation treatment with latrunculin A (LatA), an actin polymerization inhibitor, on in vitro and in vivo development of somatic cell nuclear transfer (SCNT) embryos derived from kidney fibroblasts of an aged Clawn miniature boar (12 years old). After electric activation, SCNT embryos were treated with 0, 0.5 or 1 μM LatA and cultured in vitro. The rate of blastocyst formation was significantly higher (P<0.05) in SCNT embryos treated with 0.5 μM LatA (38%) than those in control (14%). When cloned embryos treated with 0.5 μM LatA were transferred into the oviducts of two recipient miniature gilts to assess their development in vivo, both recipients became pregnant; one maintained pregnancy to term, and a live piglet (weighing 220 g) was delivered by Caesarean section. The results of this study indicated that the postactivation treatment with LatA was effective in improving in vitro developmental capacity of SCNT miniature pig embryos derived from kidney fibroblasts of an aged animal and that miniature pig cloned embryos treated with LatA had the ability to develop to term.
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Affiliation(s)
- Takehiro Himaki
- Laboratory of Animal Reproduction, Faculty of Agriculture, Kagoshima University, Kagoshima 890-0065, Japan
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19
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Methylation characteristics and developmental potential of Guangxi Bama minipig (Sus scrofa domestica) cloned embryos from donor cells treated with trichostatin A and 5-aza-2'-deoxycytidine. ZYGOTE 2012; 21:178-86. [PMID: 22355002 DOI: 10.1017/s0967199411000797] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Summary Reprogramming of DNA methylation in somatic cell nuclear transfer (SCNT) embryos is incomplete, and aberrant DNA methylation patterns are related to the inefficiency of SCNT. To facilitate nuclear reprogramming, this study investigated the effect of treating Guangxi Bama minipig donor cells with trichostatin A (TSA), 5-aza-2'-deoxycytine (5-aza-dC), or combination of TSA and 5-aza-dC prior to nuclear transfer. Analyses showed that there were no major changes in cell-cycle status among all groups. We monitored the transcription of DNMT1, DNMT3a, HDAC1 and IGF2 genes in donor cells. Transcription levels of HDAC1 were decreased significantly after treatment with a combination of TSA and 5-aza-dC, along with a significantly increased level of IGF2 (P < 0.05). Although treatment of donor cells with either TSA or 5-aza-dC alone resulted in non-significant effects in blastocyst formation rate and DNA methylation levels, a combination of TSA and 5-aza-dC significantly improved the development rates of minipig SCNT embryos to blastocyst (25.6% vs. 16.0%, P < 0.05). This change was accompanied by decreased levels of DNA methylation in somatic cells and blastocyst (P < 0.05). Thus in combination with TSA, lower concentrations of 5-aza-dC may produce a potent demethylating activity, and lead to the significantly enhanced blastocyst development percentage of Bama minipig SCNT embryos.
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20
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WHITWORTH KRISTINM, PRATHER RANDALLS. Somatic cell nuclear transfer efficiency: how can it be improved through nuclear remodeling and reprogramming? Mol Reprod Dev 2010; 77:1001-15. [PMID: 20931660 PMCID: PMC4718708 DOI: 10.1002/mrd.21242] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2010] [Accepted: 08/23/2010] [Indexed: 01/01/2023]
Abstract
Fertile offspring from somatic cell nuclear transfer (SCNT) is the goal of most cloning laboratories. For this process to be successful, a number of events must occur correctly. First the donor nucleus must be in a state that is amenable to remodeling and subsequent genomic reprogramming. The nucleus must be introduced into an oocyte cytoplasm that is capable of facilitating the nuclear remodeling. The oocyte must then be adequately stimulated to initiate development. Finally the resulting embryo must be cultured in an environment that is compatible with the development of that particular embryo. Much has been learned about the incredible changes that occur to a nucleus after it is placed in the cytoplasm of an oocyte. While we think that we are gaining an understanding of the reorganization that occurs to proteins in the donor nucleus, the process of cloning is still very inefficient. Below we will introduce the procedures for SCNT, discuss nuclear remodeling and reprogramming, and review techniques that may improve reprogramming. Finally we will briefly touch on other aspects of SCNT that may improve the development of cloned embryos.
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Affiliation(s)
| | - RANDALL S. PRATHER
- Division of Animal Sciences, University of Missouri, Columbia, Missouri
- National Swine Resource and Research Center, University of Missouri, Columbia, Missouri
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21
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Zhao J, Whyte J, Prather RS. Effect of epigenetic regulation during swine embryogenesis and on cloning by nuclear transfer. Cell Tissue Res 2010; 341:13-21. [PMID: 20563602 DOI: 10.1007/s00441-010-1000-x] [Citation(s) in RCA: 74] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2010] [Accepted: 05/23/2010] [Indexed: 01/08/2023]
Abstract
Swine play important roles as models of human disease. A combination of genetic modification with somatic cell nuclear transfer (SCNT) holds the promise of uncovering the pathogenesis of human diseases and then of developing therapeutic protocols. Unfortunately, the mechanism(s) of nuclear remodeling (a change in the structure of the nucleus) and reprogramming (a change in the transcriptional profile) during SCNT remains unclear. Incomplete remodeling is thought to cause lower cloning efficiency and abnormalities in cloned embryos and offspring. Here, we review the epigenetic regulatory and remodeling events that occur during preimplantation development of embryos derived from fertilization or SCNT, with a focus on DNA methylation and histone modifications. The discussion ends with a description of attempts at assisted remodeling of the donor somatic cell nucleus and the SCNT embryo.
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Affiliation(s)
- Jianguo Zhao
- National Swine Resource and Research Center, University of Missouri, Columbia, MO 65211, USA
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22
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Martinez-Diaz MA, Che L, Albornoz M, Seneda MM, Collis D, Coutinho ARS, El-Beirouthi N, Laurin D, Zhao X, Bordignon V. Pre- and postimplantation development of swine-cloned embryos derived from fibroblasts and bone marrow cells after inhibition of histone deacetylases. Cell Reprogram 2010; 12:85-94. [PMID: 20132016 DOI: 10.1089/cell.2009.0047] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
The present study assessed changes in epigenetic markers and pre- and postimplantation development in somatic cell nuclear transfer (SCNT) porcine embryos after treatment with the inhibitor of histone deacetylases (HDACi), Trichostatin A (TSA). Embryos were generated using in vitro matured oocytes and nuclei from either a male fetal fibroblast (FF) cell line or bone marrow cells (BMC) from three adult sows. After nuclear transfer, oocytes were either exposed or not to 10 ng/mL TSA for 10 h starting 1 h after cell fusion. Samples of one-cell stage and cleaved (two- to four-cell stage) embryos were fixed at 15 to 18 h or 46 to 48 h after cell fusion and immunocytochemically processed to detect histone H3 acetylation at lysine 14 (H3K14ac) or histone H3 dimethylation at lysine 9 (H3K9m2) using specific primary antibodies. TSA treatment increased the immunofluorescent signal for H3K14ac in cleaved embryos derived from both FF and BMC but did not affect H3K9m2. Development to the blastocyst stage was increased by TSA treatment (45.2 vs. 23.9%) in embryos produced from FF cells but not in those produced from BMC (30.6 vs. 27.4%). Cloned piglets were produced from both treatments when day 5 to 6 blastocyst-stage embryos derived from FF cells were transferred into the uterus of recipient females. Cloned piglets were also produced after the transfer of TSA-treated blastocysts derived from BMC of adult sows but not from control embryos. These findings suggest that the inhibition of histone deacetylases have similar effects on enhancing H3K14ac in SCNT embryos reconstructed from different cell types but the effect on in vitro and in vivo development seems to differ according to the nuclear donor cell type.
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Affiliation(s)
- Mario A Martinez-Diaz
- Department of Animal Science, McGill University, Ste-Anne-de-Bellevue, Québec, Canada
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23
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McLean CA, Wang Z, Babu K, Edwards A, Kasinathan P, Robl J, Sheppard AM. Normal development following chromatin transfer correlates with donor cell initial epigenetic state. Anim Reprod Sci 2009; 118:388-93. [PMID: 19632072 DOI: 10.1016/j.anireprosci.2009.06.017] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2009] [Revised: 06/10/2009] [Accepted: 06/23/2009] [Indexed: 10/20/2022]
Abstract
If the full potential of chromatin transfer (CT) technology is to be realized for both animal production and biomedical applications it is imperative that the efficiency of the reprogramming process be improved, and the potential for deleterious development be eliminated. Generation of the first cloned animals from adult somatic cells demonstrated that development is substantially an epigenetic process (Wilmut I, Schnieke AE, McWhir J, Kind AJ, Campbell KH, 1997. Viable offspring derived from fetal and adult mammalian cells. Nature. 385(6619): 810-813.). In this study, we provide preliminary evidence that the epigenetic state of the donor cell, may be valuable in assessing potential cloning success. We have measured key indicators of cellular epigenetic state in both serially derived cell populations of the same genetic origin, but differing in epigenomic status, and in a distinct cohort of donor cell populations with diverse genetic origins and epigenomic status. Specifically, the relative abundance of particular histone modifications in donor populations prior to manipulation has been correlated with the measurable variance in reprogramming efficiencies observed following CT, as defined by the number of resulting live births and healthy progeny, and the concomitant incidence of deleterious growth measures (notably the appearance of large offspring syndrome (LOS)). Thus, we suggest that the likely outcome and relative success of cloning may be predictable based on the expression of discriminating histone marks present in the donor cell population before CT. This approach may provide the basis of a prognostic signature for the future evaluation and risk assessment of putative donor cells prior to CT, and thus increase future cloning success and alleviate the incidence of abnormal development.
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Affiliation(s)
- Cameron A McLean
- AgResearch Ltd., Ruakura Research Centre, Hamilton, Private Bag 3123, New Zealand.
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24
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Cheong HT. Nuclear transfer using clonal lines of porcine fetal fibroblasts with different sizes and population doubling rates. Reprod Fertil Dev 2009; 20:871-4. [PMID: 19007550 DOI: 10.1071/rd08143] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2008] [Accepted: 07/27/2008] [Indexed: 11/23/2022] Open
Abstract
The aim of the present study was to examine the development of pig embryos produced by somatic cell nuclear transfer (NT) using the clonal lines of fetal fibroblasts with different population doublings (PD) per day and sizes. Clonal lines were established by plating fetal fibroblasts from a Day 35 pig fetus into 96-well clusters, one cell to each well. Four clonal lines (L1-L4) were selected for NT according to their PD per day (1.1 +/- 0.2 to 0.8 +/- 0.2) and mean cell size (15.1 +/- 2.0 to 20.1 +/- 2.9). Donor cells were transferred into enucleated oocytes, fused and activated simultaneously with electrical stimuli (two pulses of 125 V mm(-1) for 30 micros) and cultured for 6 days. The proportion of embryos that developed to the blastocyst stage in the L3 (19.6%) and L4 (25.3%) lines, which had a lower PD per day and larger cell size, were significantly higher (P < 0.05) than that of the L2 line (10.6%), which had a higher PD per day and the smallest cell size. The proportion of embryos developing to the blastocyst stage in the L1 line (17.3%), which had the highest PD per day and smaller cell size, was significantly lower (P < 0.05) than that of the L4 line. These results suggest that clonal lines with larger sized cell populations in mean and lower PD per day have a greater in vitro developmental potential following NT.
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Affiliation(s)
- H T Cheong
- School of Veterinary Medicine, Kangwon National University, Chuncheon, Korea.
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25
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Prather RS, Ross JW, Isom SC, Green JA. Transcriptional, post-transcriptional and epigenetic control of porcine oocyte maturation and embryogenesis. SOCIETY OF REPRODUCTION AND FERTILITY SUPPLEMENT 2009; 66:165-176. [PMID: 19848279 PMCID: PMC2842954] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Embryogenesis is a complex process that is controlled at various levels. As new discoveries are made about molecular mechanisms that control development in other species, it is apparent that these same mechanisms regulate pig embryogenesis as well. Methylation of DNA and modification of histones regulate transcription, and mechanisms such as ubiquitinization, autophagy and microRNAs regulate development post-transcriptionally. Each of these systems of regulation is highly dynamic in the early embryo. A better understanding of each of these levels of regulation can provide tools to potentially improve the reproductive process in pigs, to improve methods of creating pig embryos and cloned embryos in vitro, and to provide markers for predicting developmental competence of the embryo.
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Affiliation(s)
- R S Prather
- Division of Animal Sciences, University of Missouri, Columbia, MO 65211, USA.
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