1
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Pieri NCG, de Souza AF, Botigelli RC, Pessôa LVDF, Recchia K, Machado LS, Glória MH, de Castro RVG, Leal DF, Fantinato Neto P, Martins SMMK, Dos Santos Martins D, Bressan FF, de Andrade AFC. Porcine Primordial Germ Cell-Like Cells Generated from Induced Pluripotent Stem Cells Under Different Culture Conditions. Stem Cell Rev Rep 2021; 18:1639-1656. [PMID: 34115317 DOI: 10.1007/s12015-021-10198-8] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/02/2021] [Indexed: 12/15/2022]
Abstract
Culture conditions regulate the process of pluripotency acquisition and self-renewal. This study aimed to analyse the influence of the in vitro environment on the induction of porcine induced pluripotent stem cell (piPSCs) differentiation into primordial germ cell-like cells (pPGCLCs). piPSC culture with different supplementation strategies (LIF, bFGF, or LIF plus bFGF) promoted heterogeneous phenotypic profiles. Continuous bFGF supplementation during piPSCs culture was beneficial to support a pluripotent state and the differentiation of piPSCs into pPGCLCs. The pPGCLCs were positive for the gene and protein expression of pluripotent and germinative markers. This study can provide a suitable in vitro model for use in translational studies and to help answer numerous remaining questions about germ cells.
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Affiliation(s)
- Naira Caroline Godoy Pieri
- Department of Animal Reproduction, School of Veterinary Medicine and Animal Science, University of São Paulo, Pirassununga, SP, Brazil.
| | - Aline Fernanda de Souza
- Department of Veterinary Medicine, School of Animal Sciences and Food Engineering, SP, Pirassununga, Brazil
| | - Ramon Cesar Botigelli
- Department of Pharmacology, Institute of Biosciences, São Paulo State University (UNESP), Botucatu, SP, Brazil
| | | | - Kaiana Recchia
- Department of Surgery, Faculty of Veterinary Medicine and Animal Sciences, University of Sao Paulo, São Paulo, SP, Brazil
| | - Lucas Simões Machado
- Department of Biochemistry, Paulista School of Medicine, Federal University of São Paulo (UNIFESP), São Paulo/SP, Brazil
| | - Mayra Hirakawa Glória
- Department of Veterinary Medicine, School of Animal Sciences and Food Engineering, SP, Pirassununga, Brazil
| | - Raquel Vasconcelos Guimarães de Castro
- Department of Preventive Veterinary Medicine and Animal Reproduction, Faculty of Agricultural and Veterinary Sciences, São Paulo State University (UNESP), Jaboticabal, SP, Brazil
| | - Diego Feitosa Leal
- Department of Animal Reproduction, School of Veterinary Medicine and Animal Science, University of São Paulo, Pirassununga, SP, Brazil
| | - Paulo Fantinato Neto
- Department of Veterinary Medicine, School of Animal Sciences and Food Engineering, SP, Pirassununga, Brazil
| | | | - Daniele Dos Santos Martins
- Department of Animal Science, Faculty of Animal Science and Food Engineering, University of São Paulo, Pirassununga, Brazil
| | - Fabiana Fernandes Bressan
- Department of Veterinary Medicine, School of Animal Sciences and Food Engineering, SP, Pirassununga, Brazil
| | - André Furugen Cesar de Andrade
- Department of Animal Reproduction, School of Veterinary Medicine and Animal Science, University of São Paulo, Pirassununga, SP, Brazil
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Li Y, Qiao Y, Li F, Wang H, Dong X. Optimization of porcine embryonic germ cell culture system. In Vitro Cell Dev Biol Anim 2020; 56:808-815. [PMID: 33029688 DOI: 10.1007/s11626-020-00489-8] [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: 06/03/2020] [Accepted: 08/04/2020] [Indexed: 11/29/2022]
Abstract
Homologous feeder culture system can efficiently promote the proliferation of embryonic germ (EG) cells or embryonic stem (ES) cells while avoiding contamination by exogenous proteins and pathogens. In this study, we compared the potency of using homologous porcine embryonic fibroblasts (PEFs), gonadal stromal cells (GSCs), porcine adipose-derived stem cells (PASCs), or porcine amniotic fluid stem (PAFS) cells as feeder cells for porcine EG growth, with the commonly used mouse embryonic fibroblasts (MEFs). We compared the feeder cell growth rates; secretion of growth factors including stem cell factor (SCF), basic fibroblast growth factor (bFGF), and leukemia inhibitory factor (LIF); the effects of growth factors on porcine PGC growth; and EG growth rates when individual cells were used as feeders. Our results showed that feeder cells secreted limited amounts of growth factors, and supplementation of growth factors can significantly improve the formation of EG colonies and number of passages (P < 0.05). GSC and PEF were more suitable for EG growth because of their faster growth rate and their support on EG growth. In conclusion, this study identified novel homologous cells that can be used for EG production.
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Affiliation(s)
- Yang Li
- College of Life Science, Qingdao Agricultural University, 700 Changcheng Road, Qingdao, 266109, Shandong, People's Republic of China
| | - Yu Qiao
- College of Life Science, Qingdao Agricultural University, 700 Changcheng Road, Qingdao, 266109, Shandong, People's Republic of China
| | - Fei Li
- College of Life Science, Qingdao Agricultural University, 700 Changcheng Road, Qingdao, 266109, Shandong, People's Republic of China
| | - Hongjun Wang
- Department of Surgery,, Medical University of South Carolina, Charleston, SC, 29425, USA
| | - Xiao Dong
- College of Life Science, Qingdao Agricultural University, 700 Changcheng Road, Qingdao, 266109, Shandong, People's Republic of China.
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3
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Li F, Wang D, Song R, Cao C, Zhang Z, Wang Y, Li X, Huang J, Liu Q, Hou N, Xu B, Li X, Gao X, Jia Y, Zhao J, Wang Y. The asynchronous establishment of chromatin 3D architecture between in vitro fertilized and uniparental preimplantation pig embryos. Genome Biol 2020; 21:203. [PMID: 32778155 PMCID: PMC7418210 DOI: 10.1186/s13059-020-02095-z] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2020] [Accepted: 07/07/2020] [Indexed: 12/16/2022] Open
Abstract
BACKGROUND Pigs are important animals for agricultural and biomedical research, and improvement is needed for use of the assisted reproductive technologies. Determining underlying mechanisms of epigenetic reprogramming in the early stage of preimplantation embryos derived from in vitro fertilization (IVF), parthenogenesis, and androgenesis will not only contribute to assisted reproductive technologies of pigs but also will shed light into early human development. However, the reprogramming of three-dimensional architecture of chromatin in this process in pigs is poorly understood. RESULTS We generate three-dimensional chromatin profiles for pig somatic cells, IVF, parthenogenesis, and androgenesis preimplantation embryos. We find that the chromosomes in the pig preimplantation embryos are enriched for superdomains, which are more rare in mice. However, p(s) curves, compartments, and topologically associated domains (TADs) are largely conserved in somatic cells and are gradually established during preimplantation embryogenesis in both mammals. In the uniparental pig embryos, the establishment of chromatin architecture is highly asynchronized at all levels from IVF embryos, and a remarkably strong decompartmentalization is observed during zygotic genome activation (ZGA). Finally, chromosomes originating from oocytes always establish TADs faster than chromosomes originating from sperm, both before and during ZGA. CONCLUSIONS Our data highlight a potential unique 3D chromatin pattern of enriched superdomains in pig preimplantation embryos, an unusual decompartmentalization process during ZGA in the uniparental embryos, and an asynchronized TAD reprogramming between maternal and paternal genomes, implying a severe dysregulation of ZGA in the uniparental embryos in pigs.
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Affiliation(s)
- Feifei Li
- CAS Key Laboratory of Genome Sciences and Information, Beijing Institute of Genomics, Chinese Academy of Sciences, and China National Center for Bioinformation, Beijing, 100101 China
| | - Danyang Wang
- CAS Key Laboratory of Genome Sciences and Information, Beijing Institute of Genomics, Chinese Academy of Sciences, and China National Center for Bioinformation, Beijing, 100101 China
- University of Chinese Academy of Sciences, Beijing, 100049 China
| | - Ruigao Song
- University of Chinese Academy of Sciences, Beijing, 100049 China
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
| | - Chunwei Cao
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
- Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Medical Research Center, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, 510120 China
| | - Zhihua Zhang
- CAS Key Laboratory of Genome Sciences and Information, Beijing Institute of Genomics, Chinese Academy of Sciences, and China National Center for Bioinformation, Beijing, 100101 China
- University of Chinese Academy of Sciences, Beijing, 100049 China
| | - Yu Wang
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
- Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing, 100193 China
| | - Xiaoli Li
- CAS Key Laboratory of Genome Sciences and Information, Beijing Institute of Genomics, Chinese Academy of Sciences, and China National Center for Bioinformation, Beijing, 100101 China
- University of Chinese Academy of Sciences, Beijing, 100049 China
| | - Jiaojiao Huang
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
| | - Qiang Liu
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
| | - Naipeng Hou
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
- Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing, 100193 China
| | - Bingxiang Xu
- CAS Key Laboratory of Genome Sciences and Information, Beijing Institute of Genomics, Chinese Academy of Sciences, and China National Center for Bioinformation, Beijing, 100101 China
- University of Chinese Academy of Sciences, Beijing, 100049 China
| | - Xiao Li
- CAS Key Laboratory of Genome Sciences and Information, Beijing Institute of Genomics, Chinese Academy of Sciences, and China National Center for Bioinformation, Beijing, 100101 China
- University of Chinese Academy of Sciences, Beijing, 100049 China
| | - Xiaomeng Gao
- CAS Key Laboratory of Genome Sciences and Information, Beijing Institute of Genomics, Chinese Academy of Sciences, and China National Center for Bioinformation, Beijing, 100101 China
- University of Chinese Academy of Sciences, Beijing, 100049 China
| | - Yan Jia
- CAS Key Laboratory of Genome Sciences and Information, Beijing Institute of Genomics, Chinese Academy of Sciences, and China National Center for Bioinformation, Beijing, 100101 China
| | - Jianguo Zhao
- University of Chinese Academy of Sciences, Beijing, 100049 China
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
| | - Yanfang Wang
- Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing, 100193 China
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Choi KH, Lee DK, Oh JN, Son HY, Lee CK. FGF2 Signaling Plays an Important Role in Maintaining Pluripotent State of Pig Embryonic Germ Cells. Cell Reprogram 2018; 20:301-311. [PMID: 30204498 DOI: 10.1089/cell.2018.0019] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Germ cells are alternative sources for deriving pluripotent stem cells. Because embryonic germ cells (EGCs) possess physiological and developmental features similar to those of embryonic stem cells, pig EGCs are considered a potential tool for generating transgenic animals for agricultural usage. Therefore, in this study, we attempted to establish and characterize pig EGCs from fetal gonads. EGC lines were derived from the genital ridges of porcine fetuses in media containing leukemia inhibitory factor (LIF), fibroblast growth factor 2 (FGF2), and stem cell factor. After establishment, these cells were cultured and stabilized in LIF- or FGF2-containing media. The cell lines were maintained under both conditions over an extended time period and spontaneously differentiated into the three germ layers in vitro. Interestingly, expression of pluripotency markers showed different patterns between cell lines cultured in LIF or FGF2. SSEA4 was only expressed in FGF2-treated pig EGCs (FGF2-pEGCs), not LIF-treated pig EGCs (LIF-pEGCs). Pluripotency genes were upregulated in FGF2-pEGCs, and germline markers were highly expressed, indicating that FGF2 supplements are more efficient in supporting the pluripotency of pEGCs. In conclusion, we verified that FGF2 signaling plays an important role in reprogramming and maintaining pEGCs from fetal gonads.
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Affiliation(s)
- Kwang-Hwan Choi
- 1 Animal Biotechnology Major, Department of Agricultural Biotechnology, Research Institute of Agriculture and Life Science, Seoul National University , Seoul, Korea
| | - Dong-Kyung Lee
- 1 Animal Biotechnology Major, Department of Agricultural Biotechnology, Research Institute of Agriculture and Life Science, Seoul National University , Seoul, Korea
| | - Jong-Nam Oh
- 1 Animal Biotechnology Major, Department of Agricultural Biotechnology, Research Institute of Agriculture and Life Science, Seoul National University , Seoul, Korea
| | - Hye-Young Son
- 2 Severance Biomedical Science Institute, Severance Hospital, Yonsei University College of Medicine , Seoul, Korea
| | - Chang-Kyu Lee
- 1 Animal Biotechnology Major, Department of Agricultural Biotechnology, Research Institute of Agriculture and Life Science, Seoul National University , Seoul, Korea.,3 Institute of Green Bio Science and Technology, Seoul National University , Pyeong Chang, Kangwon do, Korea
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5
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de Souza AF, Pieri NCG, Roballo KCS, Bressan FF, Casals JB, Ambrósio CE, Perecin F, Martins DS. Dynamics of male canine germ cell development. PLoS One 2018; 13:e0193026. [PMID: 29489867 PMCID: PMC5831030 DOI: 10.1371/journal.pone.0193026] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2017] [Accepted: 02/02/2018] [Indexed: 12/18/2022] Open
Abstract
Primordial germ cells (PGCs) are precursors of gametes that can generate new individuals throughout life in both males and females. Additionally, PGCs have been shown to differentiate into embryonic germ cells (EGCs) after in vitro culture. Most studies investigating germinative cells have been performed in rodents and humans but not dogs (Canis lupus familiaris). Here, we elucidated the dynamics of the expression of pluripotent (POU5F1 and NANOG), germline (DDX4, DAZL and DPPA3), and epigenetic (5mC, 5hmC, H3K27me3 and H3K9me2) markers that are important for the development of male canine germ cells during the early (22-30 days post-fertilization (dpf)), middle (35-40 dpf) and late (45-50 dpf) gestational periods. We performed sex genotype characterization, immunofluorescence, immunohistochemistry, and quantitative reverse transcriptase polymerase chain reaction (RT-qPCR) analyses. Furthermore, in a preliminary study, we evaluated the capacity of canine embryo PGCs (30 dpf) to differentiate into EGCs. To confirm the canine EGCs phenotype, we performed alkaline phosphatase detection, immunohistochemistry, electron and transmission scanning microscopy and RT-qPCR analyses. The PGCs were positive for POU5F1 and H3K27me3 during all assessed developmental periods, including all periods between the gonadal tissue stage and foetal testes development. The number of NANOG, DDX4, DAZL, DPPA3 and 5mC-positive cells increased along with the developing cords from 35-50 dpf. Moreover, our results demonstrate the feasibility of inducing canine PGCs into putative EGCs that present pluripotent markers, such as POU5F1 and the NANOG gene, and exhibit reduced expression of germinative genes and increased expression of H3K27me3. This study provides new insight into male germ cell development mechanisms in dogs.
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Affiliation(s)
- Aline F. de Souza
- Department of Surgery, Faculty of Veterinary Medicine and Animal Sciences, University of São Paulo, São Paulo, SP, Brazil
- Department of Veterinary Medicine, Faculty of Animal Sciences and Food Engineering, University of São Paulo, Pirassununga, SP, Brazil
| | - Naira C. Godoy Pieri
- Department of Reproduction, Faculty of Veterinary Medicine, University of São Paulo, São Paulo, SP, Brazil
| | - Kelly C. S. Roballo
- Department of Veterinary Medicine, Faculty of Animal Sciences and Food Engineering, University of São Paulo, Pirassununga, SP, Brazil
| | - Fabiana F. Bressan
- Department of Surgery, Faculty of Veterinary Medicine and Animal Sciences, University of São Paulo, São Paulo, SP, Brazil
- Department of Veterinary Medicine, Faculty of Animal Sciences and Food Engineering, University of São Paulo, Pirassununga, SP, Brazil
| | - Juliana B. Casals
- Department of Surgery, Faculty of Veterinary Medicine and Animal Sciences, University of São Paulo, São Paulo, SP, Brazil
| | - Carlos E. Ambrósio
- Department of Surgery, Faculty of Veterinary Medicine and Animal Sciences, University of São Paulo, São Paulo, SP, Brazil
- Department of Veterinary Medicine, Faculty of Animal Sciences and Food Engineering, University of São Paulo, Pirassununga, SP, Brazil
| | - Felipe Perecin
- Department of Surgery, Faculty of Veterinary Medicine and Animal Sciences, University of São Paulo, São Paulo, SP, Brazil
- Department of Veterinary Medicine, Faculty of Animal Sciences and Food Engineering, University of São Paulo, Pirassununga, SP, Brazil
| | - Daniele S. Martins
- Department of Surgery, Faculty of Veterinary Medicine and Animal Sciences, University of São Paulo, São Paulo, SP, Brazil
- Department of Veterinary Medicine, Faculty of Animal Sciences and Food Engineering, University of São Paulo, Pirassununga, SP, Brazil
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6
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Tsai TS, Johnson J, White Y, John JC. The molecular characterization of porcine egg precursor cells. Oncotarget 2017; 8:63484-63505. [PMID: 28969006 PMCID: PMC5609938 DOI: 10.18632/oncotarget.18833] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2017] [Accepted: 06/03/2017] [Indexed: 12/12/2022] Open
Abstract
Female-factor infertility can be caused by poor oocyte quality and depleted ovarian reserves. Egg precursor cells (EPCs), isolated from the ovarian cortex, have the potential to be used to overcome female infertility. We aimed to define the origins of EPCs by analyzing their gene expression profiles and mtDNA content using a mini-pig model. We characterized FAC-sorted DDX4+-derived porcine EPCs by performing RNA-sequencing and determined that they utilize pathways important for cell cycle and proliferation, which supports the existence of adult mitotically active oogonial cells. Expression of the pluripotent markers Sox2 and Oct4, and the primitive germ cell markers Blimp1 and Stella were not detected. However, Nanog and Ddx4 were expressed, as were the primitive germ cell markers Fragilis, c-Kit and Tert. Moreover, porcine EPCs expressed self-renewal and proliferation markers including Myc, Esrrb, Id2, Klf4, Klf5, Stat3, Fgfr1, Fgfr2 and Il6st. The presence of Zp1, Zp2, Zp3 and Nobox were not detected, indicating that porcine EPCs are not indicative of mature primordial oocytes. We performed mitochondrial DNA Next Generation Sequencing and determined that one mtDNA variant harbored by EPCs was present in oocytes, preimplantation embryos and somatic tissues over three generations in our mini-pig model indicating the potential germline origin of EPCs.
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Affiliation(s)
- Te-Sha Tsai
- Centre for Genetic Diseases, Hudson Institute of Medical Research, Clayton, Victoria 3168, Australia.,Centre for Genetic Diseases, Department of Molecular and Translational Science, Monash University, Clayton, Victoria 3168, Australia
| | - Jacqueline Johnson
- Centre for Genetic Diseases, Hudson Institute of Medical Research, Clayton, Victoria 3168, Australia
| | | | - Justin C John
- Centre for Genetic Diseases, Hudson Institute of Medical Research, Clayton, Victoria 3168, Australia.,Centre for Genetic Diseases, Department of Molecular and Translational Science, Monash University, Clayton, Victoria 3168, Australia
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7
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Evaluation of porcine stem cell competence for somatic cell nuclear transfer and production of cloned animals. Anim Reprod Sci 2017; 178:40-49. [PMID: 28126267 DOI: 10.1016/j.anireprosci.2017.01.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2016] [Revised: 01/11/2017] [Accepted: 01/15/2017] [Indexed: 12/31/2022]
Abstract
Porcine somatic cell nuclear transfer (SCNT) has been used extensively to create genetically modified pigs, but the efficiency of the methodology is still low. It has been hypothesized that pluripotent or multipotent stem cells might result in increased SCNT efficacy as these cells are closer than somatic cells to the epigenetic state found in the blastomeres and therefore need less reprogramming. Our group has worked with porcine SCNT during the last 20 years and here we describe our experience with SCNT of 3 different stem cell lines. The porcine stem cells used were: Induced pluripotent stem cells (iPSCs) created by lentiviral doxycycline-dependent reprogramming and cultered with a GSK3β- and MEK-inhibitor (2i) and leukemia inhibitor factor (LIF) (2i LIF DOX-iPSCs), iPSCs created by a plasmid-based reprogramming and cultured with 2i and fibroblast growth factor (FGF) (2i FGF Pl-iPSCs) and embryonic germ cells (EGCs), which have earlier been characterized as being multipotent. The SCNT efficiencies of these stem cell lines were compared with that of the two fibroblast cell lines from which the iPSC lines were derived. The blastocyst rates for the 2i LIF DOX-iPSCs were 14.7%, for the 2i FGF Pl-iPSC 10.1%, and for the EGCs 34.5% compared with the fibroblast lines yielding 36.7% and 25.2%. The fibroblast- and EGC-derived embryos were used for embryo transfer and produced live offspring at similar low rates of efficiency (3.2 and 4.0%, respectively) and with several instances of malformations. In conclusion, potentially pluripotent porcine stem cells resulted in lower rates of embryonic development upon SCNT than multipotent stem cells and differentiated somatic cells.
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8
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Mechanisms of Vertebrate Germ Cell Determination. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2017; 953:383-440. [PMID: 27975276 DOI: 10.1007/978-3-319-46095-6_8] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Two unique characteristics of the germ line are the ability to persist from generation to generation and to retain full developmental potential while differentiating into gametes. How the germ line is specified that allows it to retain these characteristics within the context of a developing embryo remains unknown and is one focus of current research. Germ cell specification proceeds through one of two basic mechanisms: cell autonomous or inductive. Here, we discuss how germ plasm driven germ cell specification (cell autonomous) occurs in both zebrafish and the frog Xenopus. We describe the segregation of germ cells during embryonic development of solitary and colonial ascidians to provide an evolutionary context to both mechanisms. We conclude with a discussion of the inductive mechanism as exemplified by both the mouse and axolotl model systems. Regardless of mechanism, several general themes can be recognized including the essential role of repression and posttranscriptional regulation of gene expression.
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9
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Zhang Y, Ma J, Li H, Lv J, Wei R, Cong Y, Liu Z. bFGF signaling-mediated reprogramming of porcine primordial germ cells. Cell Tissue Res 2015; 364:429-41. [PMID: 26613602 DOI: 10.1007/s00441-015-2326-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2015] [Revised: 11/01/2015] [Accepted: 11/02/2015] [Indexed: 11/26/2022]
Abstract
Primordial germ cells (PGCs) have the ability to be reprogrammed into embryonic germ cells (EGCs) in vitro and are an alternative source of embryonic stem cells. Other than for the mouse, the systematic characterization of mammalian PGCs is still lacking, especially the process by which PGCs convert to pluripotency. This hampers the understanding of germ cell development and the derivation of authenticated EGCs from other species. We observed the morphological development of the genital ridge from Bama miniature pigs and found primary sexual differentiation in the E28 porcine embryo, coinciding with Blimp1 nuclear exclusion in PGCs. To explore molecular events involved in porcine PGC reprogramming, transcriptome data of porcine EGCs and fetal fibroblasts (FFs) were assembled and 1169 differentially expressed genes were used for Gene Ontology analysis. These genes were significantly enriched in cell-surface receptor-linked signal transduction, in agreement with the activation of LIF/Stat3 signaling and FGF signaling during the derivation of porcine EG-like cells. Using a growth-factor-defined culture system, we explored the effects of bFGF on the process and found that bFGF not only functioned at the very beginning of PGC dedifferentiation by impeding Blimp1 nuclear expression via a PI3K/AKT-dependent pathway but also maintained the viability of cultured PGCs thereafter. These results provide further insights into the development of germ cells from livestock and the mechanism of porcine PGC reprogramming.
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Affiliation(s)
- Yu Zhang
- College of Life Science, Northeast Agricultural University, Harbin, 150030, People's Republic of China
| | - Jing Ma
- College of Life Science, Northeast Agricultural University, Harbin, 150030, People's Republic of China
| | - Hai Li
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, 150001, People's Republic of China
| | - Jiawei Lv
- College of Life Science, Northeast Agricultural University, Harbin, 150030, People's Republic of China
| | - Renyue Wei
- College of Life Science, Northeast Agricultural University, Harbin, 150030, People's Republic of China
| | - Yimei Cong
- College of Life Science, Northeast Agricultural University, Harbin, 150030, People's Republic of China
- College of Veterinary Medicine, Northeast Agricultural University, Harbin, 150030, People's Republic of China
| | - Zhonghua Liu
- College of Life Science, Northeast Agricultural University, Harbin, 150030, People's Republic of China.
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10
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Dong X, Li Y, Wang H. Optimization of culture conditions for porcine embryonic germ cells. In Vitro Cell Dev Biol Anim 2015; 52:131-6. [PMID: 26487431 DOI: 10.1007/s11626-015-9962-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2015] [Accepted: 09/16/2015] [Indexed: 11/29/2022]
Affiliation(s)
- Xiao Dong
- College of Life Science, Qingdao Agricultural University, 700 Changcheng Road, Qingdao, Shandong, 266109, People's Republic of China.
| | - Yang Li
- College of Life Science, Qingdao Agricultural University, 700 Changcheng Road, Qingdao, Shandong, 266109, People's Republic of China
| | - Hongjun Wang
- Department of Surgery, Medical University of South Carolina, Charleston, SC, 29425, USA
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11
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Secher JO, Callesen H, Freude KK, Hyttel P. Initial embryology and pluripotent stem cells in the pig--The quest for establishing the pig as a model for cell therapy. Theriogenology 2015; 85:162-71. [PMID: 26474684 DOI: 10.1016/j.theriogenology.2015.09.017] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2015] [Revised: 09/03/2015] [Accepted: 09/07/2015] [Indexed: 02/07/2023]
Abstract
The quest for porcine pluripotent stem cells (PSCs) was initiated in the early 90s. Initially, it was the intention to benefit from these cells for production of genetically modified pigs using homologous recombination followed by derivation of chimeric offspring; a technology that has been used to produce genetically modified mice since the mid-80s. However, no convincing reports on the generation of bona fide porcine embryonic stem cells or embryonic germ cells resulted from these activities, and with the advent of somatic cell nuclear transfer during the late 90s, alternative methods for creating genetically modified pigs emerged. Over the past years, renewed interest in porcine PSCs has sparked activities in deriving in particular porcine induced pluripotent stem cells to develop the pig as a faithful model for studying the potentials and risks associated with induced pluripotent stem cell-based human therapy. Here, we review the recent data on establishment of porcine PSCs and the differences in embryonic development between pig and mouse, which may be underlying factors for the continuing challenge to culture and maintain porcine PSCs.
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Affiliation(s)
- Jan O Secher
- Department of Large Animal Sciences, University of Copenhagen, Frederiksberg C, Denmark.
| | - Henrik Callesen
- Department of Animal Science, Aarhus University, Tjele, Denmark
| | - Kristine K Freude
- Department of Veterinary Clinical and Animal Sciences, University of Copenhagen, Frederiksberg C, Denmark
| | - Poul Hyttel
- Department of Veterinary Clinical and Animal Sciences, University of Copenhagen, Frederiksberg C, Denmark.
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12
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Liu Y, Ostrup O, Li R, Li J, Vajta G, Kragh PM, Schmidt M, Purup S, Hyttel P, Klærke D, Callesen H. Long-term effect on in vitro cloning efficiency after treatment of somatic cells with Xenopus egg extract in the pig. Reprod Fertil Dev 2015; 26:1017-31. [PMID: 25145414 DOI: 10.1071/rd13147] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2013] [Accepted: 07/02/2013] [Indexed: 11/23/2022] Open
Abstract
In somatic cell nuclear transfer (SCNT), donor cell reprogramming is considered as a biologically important and vulnerable event. Various donor cell pre-treatments with Xenopus egg extracts can promote reprogramming. Here we investigated if the reprogramming effect of one treatment with Xenopus egg extract on donor cells was maintained for several cell passages. The extract treatment resulted in increased cell-colony formation from early passages in treated porcine fibroblasts (ExTES), and increased development of cloned embryos. Partial dedifferentiation was observed in ExTES cells, shown as a tendency towards upregulation of NANOG, c-MYC and KLF-4 and downregulation of DESMIM compared with ExTES at Passage 2. Compared with our routine SCNT, continuously increased development of cloned embryos was observed in the ExTES group, and ExTES cloned blastocysts displayed hypermethylated DNA patterns and hypermethylation of H3K4me3 and H3K27me3 in ICM compared with TE. All seven recipients became pregnant after transferral of ExTES cloned embryos and gave birth to 7-22 piglets per litter (average 12). In conclusion, our results demonstrate that one treatment of porcine fibroblasts with Xenopus egg extract can result in long-term increased ability of the cells to promote their in vitro function in subsequent SCNT. Finally these cells can also result in successful development of cloned embryos to term.
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Affiliation(s)
- Ying Liu
- Department of Animal Science, Aarhus University, DK-8830 Tjele, Denmark
| | - Olga Ostrup
- Department of Veterinary Clinical and Animal Sciences, University of Copenhagen, DK-1870 Frederiksberg C, Denmark
| | - Rong Li
- Department of Animal Science, Aarhus University, DK-8830 Tjele, Denmark
| | - Juan Li
- Department of Animal Science, Aarhus University, DK-8830 Tjele, Denmark
| | - Gábor Vajta
- Department of Animal Science, Aarhus University, DK-8830 Tjele, Denmark
| | - Peter M Kragh
- Department of Animal Science, Aarhus University, DK-8830 Tjele, Denmark
| | - Mette Schmidt
- Department of Veterinary Reproduction and Obstetrics, University of Copenhagen, DK-1870 Frederiksberg C, Denmark
| | - Stig Purup
- Department of Animal Science, Aarhus University, DK-8830 Tjele, Denmark
| | - Poul Hyttel
- Department of Veterinary Clinical and Animal Sciences, University of Copenhagen, DK-1870 Frederiksberg C, Denmark
| | - Dan Klærke
- Department of Veterinary Clinical and Animal Sciences, University of Copenhagen, DK-1870 Frederiksberg C, Denmark
| | - Henrik Callesen
- Department of Animal Science, Aarhus University, DK-8830 Tjele, Denmark
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13
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Yang F, Zhang J, Liu Y, Cheng D, Wang H. Structure and functional evaluation of porcine NANOG that is a single-exon gene and has two pseudogenes. Int J Biochem Cell Biol 2015; 59:142-52. [DOI: 10.1016/j.biocel.2014.12.009] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2014] [Revised: 12/11/2014] [Accepted: 12/15/2014] [Indexed: 12/25/2022]
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14
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Comparative transcriptomic analysis to identify differentially expressed genes in fat tissue of adult Berkshire and Jeju Native Pig using RNA-seq. Mol Biol Rep 2014; 41:6305-15. [PMID: 25008993 DOI: 10.1007/s11033-014-3513-y] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2014] [Accepted: 06/19/2014] [Indexed: 10/25/2022]
Abstract
Pork is a major source of animal protein for humans. The subcutaneous, intermuscular and the intramuscular fat are the factors responsible for meat quality. RNA-seq is rapidly adopted for the profiling of the transcriptomes in the studies related to gene regulation. The discovery of differentially expressed genes (DEGs) between adult animals of Jeju Native Pig (JNP) and Berkshire breeds are of particular interest for the current study. RNA-seq was used to investigate the transcriptome profiling in the fat tissue. Sequence reads were obtained from Ilumina HiSeq2000 and mapped to the pig genome using Tophat2. Total 153 DEGs were identified and 71 among the annotated genes, have BLAST matches in the non- redundant database. Metabolic, immune response and protein binding are enriched pathways in the fat tissue. In our study, biological adhesion, cellular, developmental and multicellular organismal processes in fat were up-regulated in JNP as compare to Berkshire. Multicellular organismal process, developmental process, embryonic morphogenesis and skeletal system development were the most significantly enriched terms in fat of JNP and Berkshire breeds (p = 1.17E-04, 0.044, 3.47E-04 and 4.48E-04 respectively). COL10A1, COL11A2, PDK4 and PNPLA3 genes responsible for skeletal system morphogenesis and body growth were down regulated in JNP. This study is the first statistical analysis for the detection of DEGs from RNA-seq data generated from fat tissue sample. This analysis can be used as stepping stone to understand the difference in the genetic mechanisms that might influence the identification of novel transcripts, sequence polymorphisms, isoforms and noncoding RNAs.
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15
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Sodhi SS, Song KD, Ghosh M, Sharma N, Lee SJ, Kim JH, Kim N, Mongre RK, Adhikari P, Kim JY, Hong SP, Oh SJ, Jeong DK. Comparative transcriptomic analysis by RNA-seq to discern differential expression of genes in liver and muscle tissues of adult Berkshire and Jeju Native Pig. Gene 2014; 546:233-42. [PMID: 24910116 DOI: 10.1016/j.gene.2014.06.005] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2014] [Revised: 05/29/2014] [Accepted: 06/04/2014] [Indexed: 12/16/2022]
Abstract
RNA-seq is being rapidly adopted for the profiling of the transcriptomes in different areas of biology, especially in the studies related to gene regulation. The discovery of differentially expressed genes (DEGs) between adult animals of Jeju Native Pig (JNP) and Berkshire breeds of Sus scrofa, is of particular interest for the current study. For the better understanding of the gene expression profiles of the liver and longissimus dorsi muscle, DEGs were identified via RNA-seq. Sequence reads were obtained from Illumina HiSeq2000 and mapped to the pig reference genome (Sscrofa10.2) using Tophat2. We identified 169 and 39 DEGs in the liver and muscle of JNP respectively, by comparison with Berkshire breed. Out of all identified genes, 41 genes in the liver and 9 genes in the muscle have given significant expression. Gene ontology (GO) terms of developmental process and KEGG pathway analysis showed that metabolic, immune response and protein binding were commonly enriched pathways in the two tissues. Further the heat map analysis by ArrayStar has shown the different levels of expression in JNP with respect to the Berkshire breed. The validation through real time PCR and western blotting also confirmed the differential expression of genes in both breeds. Genes pertaining to metabolic process and inflammatory and immune system are more enriched in Berkshire breed. This comparative transcriptome analysis of two tissues suggests a subset of novel marker genes which expressed differently between the JNP and Berkshire.
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Affiliation(s)
- Simrinder Singh Sodhi
- Department of Animal Biotechnology, Faculty of Biotechnology, Jeju National University, Jeju 690-756, South Korea
| | - Ki-Duk Song
- The Animal Genomics and Breeding Center, Hankyong National University, Anseong-si, Gyeonggi-do 456-749, South Korea
| | - Mrinmoy Ghosh
- Department of Animal Biotechnology, Faculty of Biotechnology, Jeju National University, Jeju 690-756, South Korea
| | - Neelesh Sharma
- Department of Animal Biotechnology, Faculty of Biotechnology, Jeju National University, Jeju 690-756, South Korea
| | - Sung Jin Lee
- Department of Animal Biotechnology, College of Animal Bioscience and Technology, Kangwon National University, Chuncheon 200-701, South Korea
| | - Jeong Hyun Kim
- Department of Animal Biotechnology, Faculty of Biotechnology, Jeju National University, Jeju 690-756, South Korea
| | - Nameun Kim
- Department of Animal Biotechnology, Faculty of Biotechnology, Jeju National University, Jeju 690-756, South Korea
| | - Raj Kumar Mongre
- Department of Animal Biotechnology, Faculty of Biotechnology, Jeju National University, Jeju 690-756, South Korea
| | - Pradeep Adhikari
- Department of Animal Biotechnology, Faculty of Biotechnology, Jeju National University, Jeju 690-756, South Korea
| | - Jin Young Kim
- Institute for Livestock Promotion, Jeju-do, Jeju 690-802, South Korea
| | - Sang Pyo Hong
- Institute for Livestock Promotion, Jeju-do, Jeju 690-802, South Korea
| | - Sung Jong Oh
- Department of Animal Biotechnology, Faculty of Biotechnology, Jeju National University, Jeju 690-756, South Korea
| | - Dong Kee Jeong
- Department of Animal Biotechnology, Faculty of Biotechnology, Jeju National University, Jeju 690-756, South Korea; Sustainable Agriculture Research Institute (SARI), Jeju National University, Jeju 690-756, South Korea.
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16
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Li J, Gao Y, Petkov S, Purup S, Hyttel P, Callesen H. Passage number of porcine embryonic germ cells affects epigenetic status and blastocyst rate following somatic cell nuclear transfer. Anim Reprod Sci 2014; 147:39-46. [DOI: 10.1016/j.anireprosci.2014.03.012] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2013] [Revised: 02/18/2014] [Accepted: 03/16/2014] [Indexed: 12/01/2022]
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17
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Cong Y, Ma J, Sun R, Wang J, Xue B, Wang J, Xie B, Wang J, Hu K, Liu Z. Derivation of putative porcine embryonic germ cells and analysis of their multi-lineage differentiation potential. J Genet Genomics 2013; 40:453-64. [PMID: 24053947 DOI: 10.1016/j.jgg.2013.06.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2013] [Revised: 06/12/2013] [Accepted: 06/13/2013] [Indexed: 01/22/2023]
Abstract
Embryonic germ (EG) cells are cultured pluripotent stem cells derived from the primordial germ cells (PGCs) that migrate from the dorsal mesentery of the hindgut to the developing genital ridge. In this study, the morphology of the porcine genital ridge was assessed in embryos harvested on days 22-30 of pregnancy. PGCs from embryos at these stages were cultured to obtain porcine EG cell lines, and EG-like cells were derived from PGCs from embryos harvested on days 24-28 of pregnancy. The EG-like cells expressed Oct4, Sox2, Nanog, SSEA-3, SSEA-4 and alkaline phosphatase (AP). These cells were able to form embryoid bodies (EBs) in suspension culture and differentiate into cells representative of the three germ layers as verified by a-fetoprotein (AFP), α-smooth muscle actin (α-SMA), and Nestin expression. Spontaneous differentiation from the porcine EG-like cells of delayed passage in vitro showed that they could differentiate into epithelial-like cells, mesenchymal-like cells and neuron-like cells. In vitro directed differentiation generated osteocytes, adipocytes and a variety of neural lineage cells, as demonstrated by alizarin red staining, oil red O staining, and immunofluorescence for neuronal class Ⅲ β-tubulin (Tuj1), glial fibrillary protein (GFAP) and galactosylceramidase (GALC), respectively. These results indicate that porcine EG-like cells have the potential for multi-lineage differentiation and are useful for basic porcine stem cell research.
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Affiliation(s)
- Yimei Cong
- College of Life Science, Northeast Agricultural University, Harbin 150030, China
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18
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Hall VJ. Early development of the porcine embryo: the importance of cell signalling in development of pluripotent cell lines. Reprod Fertil Dev 2013; 25:94-102. [PMID: 23244832 DOI: 10.1071/rd12264] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Understanding the cell signalling events that govern cell renewal in porcine pluripotent cells may help improve culture conditions and allow for establishment of bona fide porcine embryonic stem cells (pESC) and stable porcine induced pluripotent stem cells (piPSC). This review investigates cell signalling in the porcine preimplantation embryo containing either the inner cell mass or epiblast, with particular emphasis on fibroblast growth factor, SMAD, WNT and Janus tyrosine kinases/signal transducers and activators of transcription signalling. It is clear that key differences exist in the cell signalling events that govern pluripotency in this species compared with similar embryonic stages in mouse and human. The fact that bona fide pESC have still not been produced and that piPSC cannot survive in culture following the silencing or downregulation of the reprogramming transgenes suggest that culture conditions are not optimal. Unravelling the factor/s that regulate pluripotency in porcine embryos will pave the way for future establishment of stable pluripotent stem cell lines.
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Affiliation(s)
- Vanessa Jane Hall
- University of Copenhagen, Faculty of Health and Medical Sciences, Department of Veterinary Clinical and Animal Sciences, Gronnegaardsvej 7, DK-1870 Frederiksberg C, Denmark.
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19
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Nowak-Imialek M, Niemann H. Pluripotent cells in farm animals: state of the art and future perspectives. Reprod Fertil Dev 2013; 25:103-28. [PMID: 23244833 DOI: 10.1071/rd12265] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Pluripotent cells, such as embryonic stem (ES) cells, embryonic germ cells and embryonic carcinoma cells are a unique type of cell because they remain undifferentiated indefinitely in in vitro culture, show self-renewal and possess the ability to differentiate into derivatives of the three germ layers. These capabilities make them a unique in vitro model for studying development, differentiation and for targeted modification of the genome. True pluripotent ESCs have only been described in the laboratory mouse and rat. However, rodent physiology and anatomy differ substantially from that of humans, detracting from the value of the rodent model for studies of human diseases and the development of cellular therapies in regenerative medicine. Recently, progress in the isolation of pluripotent cells in farm animals has been made and new technologies for reprogramming of somatic cells into a pluripotent state have been developed. Prior to clinical application of therapeutic cells differentiated from pluripotent stem cells in human patients, their survival and the absence of tumourigenic potential must be assessed in suitable preclinical large animal models. The establishment of pluripotent cell lines in farm animals may provide new opportunities for the production of transgenic animals, would facilitate development and validation of large animal models for evaluating ESC-based therapies and would thus contribute to the improvement of human and animal health. This review summarises the recent progress in the derivation of pluripotent and reprogrammed cells from farm animals. We refer to our recent review on this area, to which this article is complementary.
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Affiliation(s)
- Monika Nowak-Imialek
- Institut of Farm Animal Genetics, Friedrich-Loefller-Institut (FLI), Biotechnology, Höltystrasse 10, Mariensee, 31535 Neustadt, Germany.
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20
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Wolf G, Nielsen AL, Mikkelsen JG, Pedersen FS. Epigenetic marking and repression of porcine endogenous retroviruses. J Gen Virol 2013; 94:960-970. [PMID: 23324470 DOI: 10.1099/vir.0.049288-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Endogenous retroviruses (ERVs) are remnants of retroviral germ line infections and have been identified in all mammals investigated so far. Although the majority of ERVs are degenerated, some mammalian species, such as mice and pigs, carry replication-competent ERVs capable of forming infectious viral particles. In mice, ERVs are silenced by DNA methylation and histone modifications and some exogenous retroviruses were shown to be transcriptionally repressed after integration by a primer-binding site (PBS) targeting mechanism. However, epigenetic repression of porcine ERVs (PERVs) has remained largely unexplored so far. In this study, we screened the pig genome for PERVs using LTRharvest, a tool for de novo detection of ERVs, and investigated various aspects of epigenetic repression of three unrelated PERV families. We found that these PERV families are differentially up- or downregulated upon chemical inhibition of DNA methylation and histone deacetylation in cultured porcine cells. Furthermore, chromatin immunoprecipitation analysis revealed repressive histone methylation marks at PERV loci in primary porcine embryonic germ cells and immortalized embryonic kidney cells. PERV elements belonging to the PERV-γ1 family, which is the only known PERV family that has remained active up to the present, were marked by significantly higher levels of histone methylations than PERV-γ2 and PERV-β3 proviruses. Finally, we tested three PERV-associated PBS sequences for repression activity in murine and porcine cells using retroviral transduction experiments and showed that none of these PBS sequences induced immediate transcriptional silencing in the tested primary porcine cells.
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Affiliation(s)
- Gernot Wolf
- Department of Molecular Biology and Genetics, University of Aarhus, DK-8000 Aarhus C, Denmark
| | | | | | - Finn Skou Pedersen
- Department of Molecular Biology and Genetics, University of Aarhus, DK-8000 Aarhus C, Denmark
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21
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Alberio R, Perez AR. Recent advances in stem and germ cell research: implications for the derivation of pig pluripotent cells. Reprod Domest Anim 2013; 47 Suppl 4:98-106. [PMID: 22827357 DOI: 10.1111/j.1439-0531.2012.02062.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Pluripotent stem cells have the unique capacity to contribute to all the tissues of an adult animal after transfer into a host embryo. How pluripotency is acquired during early development and how it is maintained in stem cells have attracted the interest of many scientists for over three decades. Much progress in our understanding of how stem cells arise in culture and the signals required for homoeostasis has enabled the derivation of pluripotent cells in multiple species. Here, we discuss recent developments in stem cell biology that will impact the generation of pluripotent cells from different embryonic origins and will contribute to increase our capacity for generating transgenic animals.
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Affiliation(s)
- R Alberio
- Division of Animal Sciences, School of Biosciences, University of Nottingham, Loughborough, UK.
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