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Navarro-Serna S, Piñeiro-Silva C, Fernández-Martín I, Dehesa-Etxebeste M, López de Munain A, Gadea J. Oocyte electroporation prior to in vitro fertilization is an efficient method to generate single, double, and multiple knockout porcine embryos of interest in biomedicine and animal production. Theriogenology 2024; 218:111-118. [PMID: 38320372 DOI: 10.1016/j.theriogenology.2024.01.040] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2023] [Revised: 01/31/2024] [Accepted: 01/31/2024] [Indexed: 02/08/2024]
Abstract
Genetically modified pigs play a critical role in mimicking human diseases, xenotransplantation, and the development of pigs resistant to viral diseases. The use of programmable endonucleases, including the CRISPR/Cas9 system, has revolutionized the generation of genetically modified pigs. This study evaluates the efficiency of electroporation of oocytes prior to fertilization in generating edited gene embryos for different models. For single gene editing, phospholipase C zeta (PLC ζ) and fused in sarcoma (FUS) genes were used, and the concentration of sgRNA and Cas9 complexes was optimized. The results showed that increasing the concentration resulted in higher mutation rates without affecting the blastocyst rate. Electroporation produced double knockouts for the TPC1/TPC2 genes with high efficiency (79 %). In addition, resistance to viral diseases such as PRRS and swine influenza was achieved by electroporation, allowing the generation of double knockout embryo pigs (63 %). The study also demonstrated the potential for multiple gene editing in a single step using electroporation, which is relevant for xenotransplantation. The technique resulted in the simultaneous mutation of 5 genes (GGTA1, B4GALNT2, pseudo B4GALNT2, CMAH and GHR). Overall, electroporation proved to be an efficient and versatile method to generate genetically modified embryonic pigs, offering significant advances in biomedical and agricultural research, xenotransplantation, and disease resistance. Electroporation led to the processing of numerous oocytes in a single session using less expensive equipment. We confirmed the generation of gene-edited porcine embryos for single, double, or quintuple genes simultaneously without altering embryo development to the blastocyst stage. The results provide valuable insights into the optimization of gene editing protocols for different models, opening new avenues for research and applications in this field.
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Affiliation(s)
- Sergio Navarro-Serna
- Department Physiology, University of Murcia, International Excellence Campus for Higher Education and Research "Campus Mare Nostrum" and Institute for Biomedical Research of Murcia (IMIB-Arrixaca), 30100, Murcia, Spain
| | - Celia Piñeiro-Silva
- Department Physiology, University of Murcia, International Excellence Campus for Higher Education and Research "Campus Mare Nostrum" and Institute for Biomedical Research of Murcia (IMIB-Arrixaca), 30100, Murcia, Spain
| | - Irene Fernández-Martín
- Department Physiology, University of Murcia, International Excellence Campus for Higher Education and Research "Campus Mare Nostrum" and Institute for Biomedical Research of Murcia (IMIB-Arrixaca), 30100, Murcia, Spain
| | | | - Adolfo López de Munain
- IIS Biodonostia, Neuroscience, San Sebastián, Spain; Department of Neurology. Hospital Universitario Donostia-OSAKIDETZA, San Sebastián, Spain; Department of Neurosciences. University of the Basque Country (UPV-EHU), San Sebastián, Spain; CIBERNED (CIBER), Institute Carlos III, Madrid, Spain
| | - Joaquín Gadea
- Department Physiology, University of Murcia, International Excellence Campus for Higher Education and Research "Campus Mare Nostrum" and Institute for Biomedical Research of Murcia (IMIB-Arrixaca), 30100, Murcia, Spain.
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Piñeiro-Silva C, Gadea J. Optimizing oocyte electroporation for genetic modification of porcine embryos: Evaluation of the parthenogenetic activation. Theriogenology 2024; 218:126-136. [PMID: 38325149 DOI: 10.1016/j.theriogenology.2024.01.041] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2023] [Revised: 01/31/2024] [Accepted: 01/31/2024] [Indexed: 02/09/2024]
Abstract
In reproductive biology, understanding the effects of novel techniques on early embryo development is of paramount importance. To date, the effects of electrical activation on oocytes prior to in vitro fertilization (IVF) are not well understood. The aim of this study was to investigate the effects of oocyte electroporation prior to IVF on embryo development and to differentiate between true embryos and parthenotes by using a TPCN2 knock-out (KO) male to evaluate the presence of the KO allele in the resulting blastocysts. The study consisted of three experiments. The first one examined oocyte electroporation with and without subsequent IVF and found that electroporated oocytes had higher activation rates, increased occurrence of a single pronucleus, and no effect on sperm penetration. Cleavage rates improved in electroporated oocytes, but blastocyst rates remained constant. Genotype analysis revealed a significant increase in the proportion of parthenotes in the electroporated groups compared to the IVF control (30.2 % vs. 6.8 %). The second experiment compared two electroporation media, Opti-MEM and Nuclease-Free Duplex Buffer (DB). DB induced higher oocyte degeneration rates, and lower cleavage and blastocyst rates than Opti-MEM, while parthenogenetic formation remained consistent (60.0 and 48.5 %). In the third experiment, the timing of electroporation relative to IVF was evaluated (1 h before IVF, immediately before IVF and 7 h after IVF). Electroporation immediately before IVF resulted in higher activation rates and different pronuclear proportions compared to the other timing groups. The penetration rate was higher in the immediate electroporation group, and cleavage rate improved in all electroporated groups compared to the control. Blastocyst rates remained constant. Genotyping revealed no significant differences in parthenote proportions among the timing groups, but these were higher than the control (56.25 %, 63.89 %, 51.61 %, 2.44 %, respectively), and showed higher mutation rates when electroporation was performed 7 h after IVF. Overall, this comprehensive study sheds light on the potential of electroporation for creating genetically modified embryos and the importance of media selection and timing in the process, the best media being the Opti-MEM and the more efficient timing regarding mutation rate, 7 h post-IVF, even when the parthenote formation did not differ among electroporated groups. Further studies are needed to reduce the parthenogenetic activation while maintaining high mutation rates to optimize the use of this procedure for the generation of gene-edited pig embryos by oocyte/zygote electroporation.
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Affiliation(s)
- Celia Piñeiro-Silva
- Department of Physiology, University of Murcia, International Excellence Campus for Higher Education and Research "Campus Mare Nostrum" and Institute for Biomedical Research of Murcia (IMIB-Arrixaca), 30100, Murcia, Spain
| | - Joaquín Gadea
- Department of Physiology, University of Murcia, International Excellence Campus for Higher Education and Research "Campus Mare Nostrum" and Institute for Biomedical Research of Murcia (IMIB-Arrixaca), 30100, Murcia, Spain.
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Popova J, Bets V, Kozhevnikova E. Perspectives in Genome-Editing Techniques for Livestock. Animals (Basel) 2023; 13:2580. [PMID: 37627370 PMCID: PMC10452040 DOI: 10.3390/ani13162580] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2023] [Revised: 08/08/2023] [Accepted: 08/08/2023] [Indexed: 08/27/2023] Open
Abstract
Genome editing of farm animals has undeniable practical applications. It helps to improve production traits, enhances the economic value of livestock, and increases disease resistance. Gene-modified animals are also used for biomedical research and drug production and demonstrate the potential to be used as xenograft donors for humans. The recent discovery of site-specific nucleases that allow precision genome editing of a single-cell embryo (or embryonic stem cells) and the development of new embryological delivery manipulations have revolutionized the transgenesis field. These relatively new approaches have already proven to be efficient and reliable for genome engineering and have wide potential for use in agriculture. A number of advanced methodologies have been tested in laboratory models and might be considered for application in livestock animals. At the same time, these methods must meet the requirements of safety, efficiency and availability of their application for a wide range of farm animals. This review aims at covering a brief history of livestock animal genome engineering and outlines possible future directions to design optimal and cost-effective tools for transgenesis in farm species.
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Affiliation(s)
- Julia Popova
- Laboratory of Bioengineering, Novosibirsk State Agrarian University, 630039 Novosibirsk, Russia; (J.P.); (V.B.)
| | - Victoria Bets
- Laboratory of Bioengineering, Novosibirsk State Agrarian University, 630039 Novosibirsk, Russia; (J.P.); (V.B.)
- Center of Technological Excellence, Novosibirsk State Technical University, 630073 Novosibirsk, Russia
| | - Elena Kozhevnikova
- Laboratory of Bioengineering, Novosibirsk State Agrarian University, 630039 Novosibirsk, Russia; (J.P.); (V.B.)
- Laboratory of Experimental Models of Cognitive and Emotional Disorders, Scientific-Research Institute of Neurosciences and Medicine, 630117 Novosibirsk, Russia
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Tanihara F, Hirata M, Namula Z, Wittayarat M, Do LTK, Lin Q, Takebayashi K, Hara H, Nagahara M, Otoi T. GHR-mutant pig derived from domestic pig and microminipig hybrid zygotes using CRISPR/Cas9 system. Mol Biol Rep 2023; 50:5049-5057. [PMID: 37101010 DOI: 10.1007/s11033-023-08388-3] [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: 04/05/2022] [Accepted: 03/15/2023] [Indexed: 04/28/2023]
Abstract
BACKGROUND Pigs are excellent large animal models with several similarities to humans. They provide valuable insights into biomedical research that are otherwise difficult to obtain from rodent models. However, even if miniature pig strains are used, their large stature compared with other experimental animals requires a specific maintenance facility which greatly limits their usage as animal models. Deficiency of growth hormone receptor (GHR) function causes small stature phenotypes. The establishment of miniature pig strains via GHR modification will enhance their usage as animal models. Microminipig is an incredibly small miniature pig strain developed in Japan. In this study, we generated a GHR mutant pig using electroporation-mediated introduction of the CRISPR/Cas9 system into porcine zygotes derived from domestic porcine oocytes and microminipig spermatozoa. METHODS AND RESULTS First, we optimized the efficiency of five guide RNAs (gRNAs) designed to target GHR in zygotes. Embryos that had been electroporated with the optimized gRNAs and Cas9 were then transferred into recipient gilts. After embryo transfer, 10 piglets were delivered, and one carried a biallelic mutation in the GHR target region. The GHR biallelic mutant showed a remarkable growth-retardation phenotype. Furthermore, we obtained F1 pigs derived from the mating of GHR biallelic mutant with wild-type microminipig, and GHR biallelic mutant F2 pigs through sib-mating of F1 pigs. CONCLUSIONS We have successfully demonstrated the generation of biallelic GHR-mutant small-stature pigs. Backcrossing of GHR-deficient pig with microminipig will establish the smallest pig strain which can contribute significantly to the field of biomedical research.
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Affiliation(s)
- Fuminori Tanihara
- Faculty of Bioscience and Bioindustry, Tokushima University, Ishii, Myozai-gun, Tokushima, 7793233, Japan
| | - Maki Hirata
- Faculty of Bioscience and Bioindustry, Tokushima University, Ishii, Myozai-gun, Tokushima, 7793233, Japan
- Bio-Innovation Research Center, Tokushima University, Ishii, Myozai-gun, Tokushima, 7793233, Japan
| | - Zhao Namula
- Faculty of Bioscience and Bioindustry, Tokushima University, Ishii, Myozai-gun, Tokushima, 7793233, Japan
- College of Coastal Agricultural Sciences, Guangdong Ocean University, Zhanjiang, 524088, China
| | - Manita Wittayarat
- Faculty of Veterinary Science, Prince of Songkla University, Songkhla, 90110, Thailand
| | - Lanh Thi Kim Do
- Faculty of Bioscience and Bioindustry, Tokushima University, Ishii, Myozai-gun, Tokushima, 7793233, Japan
- Faculty of Veterinary Medicine, Vietnam National University of Agriculture, Hanoi, 100000, Vietnam
| | - Qingyi Lin
- Faculty of Bioscience and Bioindustry, Tokushima University, Ishii, Myozai-gun, Tokushima, 7793233, Japan
- Bio-Innovation Research Center, Tokushima University, Ishii, Myozai-gun, Tokushima, 7793233, Japan
| | - Koki Takebayashi
- Faculty of Bioscience and Bioindustry, Tokushima University, Ishii, Myozai-gun, Tokushima, 7793233, Japan
- Bio-Innovation Research Center, Tokushima University, Ishii, Myozai-gun, Tokushima, 7793233, Japan
| | - Hiromasa Hara
- Division of Regenerative Medicine, Center for Molecular Medicine, Jichi Medical University, Tochigi, 3290498, Japan
- Laboratory of Regenerative And Cellular Medicine, Jichi Medical University, Tochigi, 3290498, Japan
| | - Megumi Nagahara
- Faculty of Bioscience and Bioindustry, Tokushima University, Ishii, Myozai-gun, Tokushima, 7793233, Japan
- Bio-Innovation Research Center, Tokushima University, Ishii, Myozai-gun, Tokushima, 7793233, Japan
| | - Takeshige Otoi
- Faculty of Bioscience and Bioindustry, Tokushima University, Ishii, Myozai-gun, Tokushima, 7793233, Japan.
- Bio-Innovation Research Center, Tokushima University, Ishii, Myozai-gun, Tokushima, 7793233, Japan.
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Suitability of a universal electroporation device for genome editing and production of transgenic rats. Reprod Biol 2023; 23:100755. [PMID: 36933474 DOI: 10.1016/j.repbio.2023.100755] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2023] [Revised: 03/03/2023] [Accepted: 03/04/2023] [Indexed: 03/18/2023]
Abstract
Mammalian genome editing has utilized expensive and highly specialized electroporator devices. The "Gene Pulser XCell," a modular electroporation system for transfecting all cell types, has not been used extensively in mammalian embryo genome editing. The present experiment was undertaken to determine the usefulness of the Gene Pulser XCell for inserting the CRISPR/Cas9 system into intact zygotes in order to obtain the enhanced green fluorescent protein reporter rats (eGFP-R). An electroporation pulse response test using mCherry mRNA was performed to optimize the settings of the electroporator. Forty-five combinations of five pulse voltages (15, 25, 30, 35 and 40 V), three pulse durations (5, 10 and 25 ms), and three pulse frequencies (2, 5 and 6 pulses) applied at a constant 100-ms pulse interval and temperature of 37.5 °C were evaluated. The test revealed that the 35 V was the only voltage suitable for insertion of mCherry mRNA into intact rat zygotes and the only one that resulted in the production of embryos attaining the blastocyst stage. The incorporation of mCherry mRNA increased but the survival of the electroporated embryos declined with an increment in the number of pulses. Subsequent transfer of 1112 surviving Sprague Dawley rat embryos (after 8 h of incubating 1800 zygotes electroporated with the CRISPR/Cas9) resulted in the production of 287 offspring (25.8%). Ensuing PCR and phenotypic evaluation confirmed that twenty animals (6.96%) expressed eGFP in all body organs/tissues except for blood and blood vessels. The mortality of males and females before the attainment of puberty was 2 and 3 pups, respectively, and the final number/ratio of male to female of offspring was 9:11. All the surviving rats mated naturally and successfully transmitted the GFP transgene to their progeny. The Gene Pulser XCell total system with the settings predetermined in the present experiment can effectively be used to produce transgenic rats through the CRISPR/Cas9-mediated genome editing of zygotes.
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Tanihara F, Hirata M, Otoi T. GEEP Method: An Optimized Electroporation-Mediated Gene Editing Approach for Establishment of Knockout Pig Lines. Methods Mol Biol 2023; 2637:293-300. [PMID: 36773155 DOI: 10.1007/978-1-0716-3016-7_22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/27/2023]
Abstract
Pigs are excellent large animal models owing to their several physiological and anatomical similarities to humans. Somatic cell nuclear transfer using gene-modified cells is the mainstream approach for generating genetically modified pigs. Recent advances in improving gene editors such as the CRISPR/Cas9 system have enabled direct gene modification in zygotes/embryos. Here, we describe the gene editing by electroporation of Cas9 protein (GEEP) method, an optimized electroporation-mediated method for the introduction of CRISPR/Cas9 into porcine zygotes/embryos. The simplicity and micromanipulation-free procedures are the major advantages of this method.
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Affiliation(s)
- Fuminori Tanihara
- Center for Development of Advanced Medical Technology, Jichi Medical University, Tochigi, Japan
| | - Maki Hirata
- Faculty of Bioscience and Bioindustry, Tokushima University, Tokushima, Japan
- Bio-Innovation Research Center, Tokushima University, Tokushima, Japan
| | - Takeshige Otoi
- Faculty of Bioscience and Bioindustry, Tokushima University, Tokushima, Japan.
- Bio-Innovation Research Center, Tokushima University, Tokushima, Japan.
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Navarro-Serna S, Dehesa-Etxebeste M, Piñeiro-Silva C, Romar R, Lopes JS, López de Munaín A, Gadea J. Generation of Calpain-3 knock-out porcine embryos by CRISPR-Cas9 electroporation and intracytoplasmic microinjection of oocytes before insemination. Theriogenology 2022; 186:175-184. [DOI: 10.1016/j.theriogenology.2022.04.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2022] [Revised: 04/17/2022] [Accepted: 04/19/2022] [Indexed: 01/31/2023]
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Namula Z, Hirata M, Le QA, Lin Q, Takebayashi K, Yoshimura N, Tanihara F, Thongkittidilok C, Otoi T. Zona pellucida treatment before CRISPR/Cas9-mediated genome editing of porcine zygotes. Vet Med Sci 2021; 8:164-169. [PMID: 34674375 PMCID: PMC8788957 DOI: 10.1002/vms3.659] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Background Increasing the permeability of the zona pellucida (ZP) of oocytes before CRISPR/Cas9 electroporation may improve the efficiency of gene editing; however, the effects of this approach on subsequent developmental processes are unclear. In this study, the effects of ZP treatment before electroporation on embryonic development and gene editing in porcine embryos were evaluated. Methods The ZP of zygotes was weakened or removed by exposure to 0.5% actinase E, followed by electroporation of the Cas9 protein with guide RNA targeting GGTA1. Results The blastocyst formation rate of ZP‐free zygotes after electroporation was significantly lower (p < 0.05) than that of ZP‐intact zygotes. The mutation rate in blastocysts from ZP‐weakened zygotes was similar to that in ZP‐intact zygotes, whereas ZP removal increased the mutation rate. The mutation efficiency in blastocysts from electroporated zygotes did not differ among ZP treatment groups. Conclusions Our results indicate that weakening the ZP does not affect the developmental competence, mutation rate, or mutation efficiency of electroporated zygotes, whereas ZP removal has a detrimental effect on embryonic development but may increase the mutation rate.
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Affiliation(s)
- Zhao Namula
- Faculty of Veterinary Science, Guangdong Ocean University, Zhanjiang, China.,Faculty of Bioscience and Bioindustry, Tokushima University, Tokushima, Japan
| | - Maki Hirata
- Faculty of Bioscience and Bioindustry, Tokushima University, Tokushima, Japan
| | - Quynh Anh Le
- Faculty of Bioscience and Bioindustry, Tokushima University, Tokushima, Japan
| | - Qingyi Lin
- Faculty of Bioscience and Bioindustry, Tokushima University, Tokushima, Japan
| | - Koki Takebayashi
- Faculty of Bioscience and Bioindustry, Tokushima University, Tokushima, Japan
| | - Naoaki Yoshimura
- Faculty of Bioscience and Bioindustry, Tokushima University, Tokushima, Japan
| | - Fuminori Tanihara
- Faculty of Bioscience and Bioindustry, Tokushima University, Tokushima, Japan
| | | | - Takeshige Otoi
- Faculty of Bioscience and Bioindustry, Tokushima University, Tokushima, Japan
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Wittayarat M, Hirata M, Namula Z, Sato Y, Nguyen NT, Le QA, Lin Q, Takebayashi K, Tanihara F, Otoi T. Introduction of a point mutation in the KRAS gene of in vitro fertilized porcine zygotes via electroporation of the CRISPR/Cas9 system with single-stranded oligodeoxynucleotides. Anim Sci J 2021; 92:e13534. [PMID: 33638256 DOI: 10.1111/asj.13534] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2020] [Revised: 11/21/2020] [Accepted: 02/08/2021] [Indexed: 01/02/2023]
Abstract
This study aimed to investigate the efficiency of KRAS gene editing via CRISPR/Cas9 delivery by electroporation and analyzed the effects of the non-homologous end-joining pathway inhibitor Scr7 and single-stranded oligodeoxynucleotide (ssODN) homology arm length on introducing a point mutation in KRAS. Various concentrations (0-2 µM) of Scr7 were evaluated; all concentrations of Scr7 including 0 µM resulted in the generation of blastocysts with a point mutation and the wild-type sequence or indels. No significant differences in the blastocyst formation rates of electroporated zygotes were observed among ssODN homology arm lengths, irrespective of the gRNA (gRNA1 and gRNA2). The proportion of blastocysts carrying a point mutation with or without the wild-type sequence and indels was significantly higher in the ssODN20 group (i.e., the group with a ssODN homology arm of 20 bp) than in the ssODN60 group (gRNA1: 25.7% vs. 5.4% and gRNA2: 45.5% vs. 5.9%, p < .05). In conclusion, the CRISPR/Cas9 delivery with ssODN via electroporation is feasible for the generation of point mutations in porcine embryos. Further studies are required to improve the efficiency and accuracy of the homology-directed repair.
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Affiliation(s)
- Manita Wittayarat
- Faculty of Bioscience and Bioindustry, Tokushima University, Tokushima, Japan.,Faculty of Veterinary Science, Prince of Songkla University, Songkhla, Thailand
| | - Maki Hirata
- Faculty of Bioscience and Bioindustry, Tokushima University, Tokushima, Japan
| | - Zhao Namula
- Faculty of Bioscience and Bioindustry, Tokushima University, Tokushima, Japan.,College of Agricultural Science, Guangdong Ocean University, Guangdong, China
| | - Yoko Sato
- School of Biological Science, Tokai University, Sapporo, Japan
| | - Nhien T Nguyen
- Faculty of Bioscience and Bioindustry, Tokushima University, Tokushima, Japan
| | - Quynh A Le
- Faculty of Bioscience and Bioindustry, Tokushima University, Tokushima, Japan
| | - Qingyi Lin
- Faculty of Bioscience and Bioindustry, Tokushima University, Tokushima, Japan
| | - Koki Takebayashi
- Faculty of Bioscience and Bioindustry, Tokushima University, Tokushima, Japan
| | - Fuminori Tanihara
- Faculty of Bioscience and Bioindustry, Tokushima University, Tokushima, Japan
| | - Takeshige Otoi
- Faculty of Bioscience and Bioindustry, Tokushima University, Tokushima, Japan
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Namula Z, Isumi Y, Sato Y, Le Q, Lin Q, Takebayashi K, Hirata M, Tanihara F, Thongkittidilok C, Otoi T. Improvement of the in vitro fertilization and embryo development using frozen-thawed spermatozoa of microminipigs. Arch Anim Breed 2021; 64:265-271. [PMID: 34189254 PMCID: PMC8223014 DOI: 10.5194/aab-64-265-2021] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2020] [Accepted: 05/25/2021] [Indexed: 11/17/2022] Open
Abstract
This study aimed to compare the quality and the penetration ability of frozen-thawed spermatozoa from three microminipigs and Large White boars and to evaluate the effects of caffeine and heparin as well as the sperm-oocyte co-incubation length on the fertilization and embryonic development in vitro. Results showed that the fertilization rates of spermatozoa from three microminipig boars were significantly lower than those of a Large White boar. In the post-thaw spermatozoa from one of three microminipig boars, the sperm quality, penetration ability, and the oocyte development after in vitro fertilization were significantly lower than those of the spermatozoa from other boars. The caffeine supplementation in the fertilization media increased the rates of fertilization and blastocyst formation for the microminipig spermatozoa with low sperm quality. In addition to caffeine supplementation, the rates of fertilization and blastocyst formation after using microminipig spermatozoa were significantly higher with a 10 h sperm-oocyte co-incubation than with 3 h of co-incubation length. Our results indicate that the differences between the males and the breed influence the quality and fertility of frozen-thawed boar spermatozoa. In conclusion, the presence of caffeine in the in vitro fertilization (IVF) medium and adequate length of sperm-oocyte co-incubation may have beneficial effects for improving IVF results when using microminipig spermatozoa with low quality.
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Affiliation(s)
- Zhao Namula
- Faculty of Veterinary Science, Guangdong Ocean University, Zhanjiang,
China
- Faculty of Bioscience and Bioindustry, Tokushima University,
Tokushima, Japan
| | - Yasuhiro Isumi
- Faculty of Bioscience and Bioindustry, Tokushima University,
Tokushima, Japan
| | - Yoko Sato
- School of Biological Science, Tokai University, Sapporo, Japan
| | - Quynh Anh Le
- Faculty of Bioscience and Bioindustry, Tokushima University,
Tokushima, Japan
| | - Qingyi Lin
- Faculty of Bioscience and Bioindustry, Tokushima University,
Tokushima, Japan
| | - Koki Takebayashi
- Faculty of Bioscience and Bioindustry, Tokushima University,
Tokushima, Japan
| | - Maki Hirata
- Faculty of Veterinary Science, Guangdong Ocean University, Zhanjiang,
China
- Faculty of Bioscience and Bioindustry, Tokushima University,
Tokushima, Japan
| | - Fuminori Tanihara
- Faculty of Veterinary Science, Guangdong Ocean University, Zhanjiang,
China
- Faculty of Bioscience and Bioindustry, Tokushima University,
Tokushima, Japan
| | | | - Takeshige Otoi
- Faculty of Veterinary Science, Guangdong Ocean University, Zhanjiang,
China
- Faculty of Bioscience and Bioindustry, Tokushima University,
Tokushima, Japan
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11
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Zhang J, Khazalwa EM, Abkallo HM, Zhou Y, Nie X, Ruan J, Zhao C, Wang J, Xu J, Li X, Zhao S, Zuo E, Steinaa L, Xie S. The advancements, challenges, and future implications of the CRISPR/Cas9 system in swine research. J Genet Genomics 2021; 48:347-360. [PMID: 34144928 DOI: 10.1016/j.jgg.2021.03.015] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2020] [Revised: 03/10/2021] [Accepted: 03/13/2021] [Indexed: 12/11/2022]
Abstract
Clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9 (CRISPR/Cas9) genome editing technology has dramatically influenced swine research by enabling the production of high-quality disease-resistant pig breeds, thus improving yields. In addition, CRISPR/Cas9 has been used extensively in pigs as one of the tools in biomedical research. In this review, we present the advancements of the CRISPR/Cas9 system in swine research, such as animal breeding, vaccine development, xenotransplantation, and disease modeling. We also highlight the current challenges and some potential applications of the CRISPR/Cas9 technologies.
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Affiliation(s)
- Jinfu Zhang
- Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education & Key Lab of Swine Genetics and Breeding of Ministry of Agriculture and Rural Affairs, Huazhong Agricultural University, Wuhan 430070, PR China
| | - Emmanuel M Khazalwa
- Animal and Human Health Program, Biosciences, International Livestock Research Institute (ILRI), P.O. Box 30709, Nairobi 00100, Kenya
| | - Hussein M Abkallo
- Animal and Human Health Program, Biosciences, International Livestock Research Institute (ILRI), P.O. Box 30709, Nairobi 00100, Kenya
| | - Yuan Zhou
- Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education & Key Lab of Swine Genetics and Breeding of Ministry of Agriculture and Rural Affairs, Huazhong Agricultural University, Wuhan 430070, PR China
| | - Xiongwei Nie
- Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education & Key Lab of Swine Genetics and Breeding of Ministry of Agriculture and Rural Affairs, Huazhong Agricultural University, Wuhan 430070, PR China
| | - Jinxue Ruan
- Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education & Key Lab of Swine Genetics and Breeding of Ministry of Agriculture and Rural Affairs, Huazhong Agricultural University, Wuhan 430070, PR China
| | - Changzhi Zhao
- Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education & Key Lab of Swine Genetics and Breeding of Ministry of Agriculture and Rural Affairs, Huazhong Agricultural University, Wuhan 430070, PR China
| | - Jieru Wang
- Key Laboratory of Pig Molecular Quantitative Genetics of Anhui Academy of Agricultural Sciences, Livestock and Poultry Epidemic Diseases Research Center of Anhui Province, Anhui Provincial Key Laboratory of Livestock and Poultry Product Safety Engineering, Institute of Animal Husbandry and Veterinary Medicine, Anhui Academy of Agricultural Sciences, Hefei 230031, PR China
| | - Jing Xu
- Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education & Key Lab of Swine Genetics and Breeding of Ministry of Agriculture and Rural Affairs, Huazhong Agricultural University, Wuhan 430070, PR China
| | - Xinyun Li
- Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education & Key Lab of Swine Genetics and Breeding of Ministry of Agriculture and Rural Affairs, Huazhong Agricultural University, Wuhan 430070, PR China; The Cooperative Innovation Center for Sustainable Pig Production, Huazhong Agricultural University, Wuhan 430070, PR China
| | - Shuhong Zhao
- Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education & Key Lab of Swine Genetics and Breeding of Ministry of Agriculture and Rural Affairs, Huazhong Agricultural University, Wuhan 430070, PR China; The Cooperative Innovation Center for Sustainable Pig Production, Huazhong Agricultural University, Wuhan 430070, PR China
| | - Erwei Zuo
- Lingnan Guangdong Laboratory of Modern Agriculture, Genome Analysis Laboratory of the Ministry of Agriculture, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen 518124, PR China.
| | - Lucilla Steinaa
- Animal and Human Health Program, Biosciences, International Livestock Research Institute (ILRI), P.O. Box 30709, Nairobi 00100, Kenya.
| | - Shengsong Xie
- Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education & Key Lab of Swine Genetics and Breeding of Ministry of Agriculture and Rural Affairs, Huazhong Agricultural University, Wuhan 430070, PR China; Animal and Human Health Program, Biosciences, International Livestock Research Institute (ILRI), P.O. Box 30709, Nairobi 00100, Kenya; The Cooperative Innovation Center for Sustainable Pig Production, Huazhong Agricultural University, Wuhan 430070, PR China.
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12
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Lin JC, Van Eenennaam AL. Electroporation-Mediated Genome Editing of Livestock Zygotes. Front Genet 2021; 12:648482. [PMID: 33927751 PMCID: PMC8078910 DOI: 10.3389/fgene.2021.648482] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2020] [Accepted: 03/22/2021] [Indexed: 12/20/2022] Open
Abstract
The introduction of genome editing reagents into mammalian zygotes has traditionally been accomplished by cytoplasmic or pronuclear microinjection. This time-consuming procedure requires expensive equipment and a high level of skill. Electroporation of zygotes offers a simplified and more streamlined approach to transfect mammalian zygotes. There are a number of studies examining the parameters used in electroporation of mouse and rat zygotes. Here, we review the electroporation conditions, timing, and success rates that have been reported for mice and rats, in addition to the few reports about livestock zygotes, specifically pigs and cattle. The introduction of editing reagents at, or soon after, fertilization can help reduce the rate of mosaicism, the presence of two of more genotypes in the cells of an individual; as can the introduction of nuclease proteins rather than mRNA encoding nucleases. Mosaicism is particularly problematic in large livestock species with long generation intervals as it can take years to obtain non-mosaic, homozygous offspring through breeding. Gene knockouts accomplished via the non-homologous end joining pathway have been more widely reported and successfully accomplished using electroporation than have gene knock-ins. Delivering large DNA plasmids into the zygote is hindered by the zona pellucida (ZP), and the majority of gene knock-ins accomplished by electroporation have been using short single stranded DNA (ssDNA) repair templates, typically less than 1 kb. The most promising approach to deliver larger donor repair templates of up to 4.9 kb along with genome editing reagents into zygotes, without using cytoplasmic injection, is to use recombinant adeno-associated viruses (rAAVs) in combination with electroporation. However, similar to other methods used to deliver clustered regularly interspaced palindromic repeat (CRISPR) genome-editing reagents, this approach is also associated with high levels of mosaicism. Recent developments complementing germline ablated individuals with edited germline-competent cells offer an approach to avoid mosaicism in the germline of genome edited founder lines. Even with electroporation-mediated delivery of genome editing reagents to mammalian zygotes, there remain additional chokepoints in the genome editing pipeline that currently hinder the scalable production of non-mosaic genome edited livestock.
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Affiliation(s)
- Jason C Lin
- Department of Animal Science, University of California, Davis, Davis, CA, United States
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13
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Abstract
Genetically modified animals, especially rodents, are widely used in biomedical research. However, non-rodent models are required for efficient translational medicine and preclinical studies. Owing to the similarity in the physiological traits of pigs and humans, genetically modified pigs may be a valuable resource for biomedical research. Somatic cell nuclear transfer (SCNT) using genetically modified somatic cells has been the primary method for the generation of genetically modified pigs. However, site-specific gene modification in porcine cells is inefficient and requires laborious and time-consuming processes. Recent improvements in gene-editing systems, such as zinc finger nucleases, transcription activator-like effector nucleases, and the clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein (CRISPR/Cas) system, represent major advances. The efficient introduction of site-specific modifications into cells via gene editors dramatically reduces the effort and time required to generate genetically modified pigs. Furthermore, gene editors enable direct gene modification during embryogenesis, bypassing the SCNT procedure. The application of gene editors has progressively expanded, and a range of strategies is now available for porcine gene engineering. This review provides an overview of approaches for the generation of genetically modified pigs using gene editors, and highlights the current trends, as well as the limitations, of gene editing in pigs.
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Affiliation(s)
- Fuminori Tanihara
- Faculty of Bioscience and Bioindustry, Tokushima University, Tokushima 770-8513, Japan.,Center for Development of Advanced Medical Technology, Jichi Medical University, Tochigi 329-0498, Japan
| | - Maki Hirata
- Faculty of Bioscience and Bioindustry, Tokushima University, Tokushima 770-8513, Japan
| | - Takeshige Otoi
- Faculty of Bioscience and Bioindustry, Tokushima University, Tokushima 770-8513, Japan
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14
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Ratner LD, La Motta GE, Briski O, Salamone DF, Fernandez-Martin R. Practical Approaches for Knock-Out Gene Editing in Pigs. Front Genet 2021; 11:617850. [PMID: 33747029 PMCID: PMC7973260 DOI: 10.3389/fgene.2020.617850] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2020] [Accepted: 12/30/2020] [Indexed: 12/18/2022] Open
Abstract
Pigs are an important resource for meat production and serve as a model for human diseases. Due to their physiological and anatomical similarities to humans, these animals can recapitulate symptoms of human diseases, becoming an effective model for biomedical research. Although, in the past pig have not been widely used partially because of the difficulty in genetic modification; nowadays, with the new revolutionary technology of programmable nucleases, and fundamentally of the CRISPR-Cas9 systems, it is possible for the first time to precisely modify the porcine genome as never before. To this purpose, it is necessary to introduce the system into early stage zygotes or to edit cells followed by somatic cell nuclear transfer. In this review, several strategies for pig knock-out gene editing, using the CRISPR-Cas9 system, will be summarized, as well as genotyping methods and different delivery techniques to introduce these tools into the embryos. Finally, the best approaches to produce homogeneous, biallelic edited animals will be discussed.
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Affiliation(s)
- Laura Daniela Ratner
- Laboratorio Biotecnología Animal (LabBA), Departamento de Producción Animal, Facultad de Agronomía, Universidad de Buenos Aires, Buenos Aires, Argentina.,Instituto de Investigaciones en Producción Animal (INPA), CONICET-Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Gaston Emilio La Motta
- Laboratorio Biotecnología Animal (LabBA), Departamento de Producción Animal, Facultad de Agronomía, Universidad de Buenos Aires, Buenos Aires, Argentina.,Instituto de Investigaciones en Producción Animal (INPA), CONICET-Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Olinda Briski
- Laboratorio Biotecnología Animal (LabBA), Departamento de Producción Animal, Facultad de Agronomía, Universidad de Buenos Aires, Buenos Aires, Argentina.,Instituto de Investigaciones en Producción Animal (INPA), CONICET-Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Daniel Felipe Salamone
- Laboratorio Biotecnología Animal (LabBA), Departamento de Producción Animal, Facultad de Agronomía, Universidad de Buenos Aires, Buenos Aires, Argentina.,Instituto de Investigaciones en Producción Animal (INPA), CONICET-Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Rafael Fernandez-Martin
- Laboratorio Biotecnología Animal (LabBA), Departamento de Producción Animal, Facultad de Agronomía, Universidad de Buenos Aires, Buenos Aires, Argentina.,Instituto de Investigaciones en Producción Animal (INPA), CONICET-Universidad de Buenos Aires, Buenos Aires, Argentina
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15
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One-Step Generation of Multiple Gene-Edited Pigs by Electroporation of the CRISPR/Cas9 System into Zygotes to Reduce Xenoantigen Biosynthesis. Int J Mol Sci 2021; 22:ijms22052249. [PMID: 33668187 PMCID: PMC7956194 DOI: 10.3390/ijms22052249] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2021] [Revised: 02/18/2021] [Accepted: 02/20/2021] [Indexed: 02/08/2023] Open
Abstract
Xenoantigens cause hyperacute rejection and limit the success of interspecific xenografts. Therefore, genes involved in xenoantigen biosynthesis, such as GGTA1, CMAH, and B4GALNT2, are key targets to improve the outcomes of xenotransplantation. In this study, we introduced a CRISPR/Cas9 system simultaneously targeting GGTA1, CMAH, and B4GALNT2 into in vitro-fertilized zygotes using electroporation for the one-step generation of multiple gene-edited pigs without xenoantigens. First, we optimized the combination of guide RNAs (gRNAs) targeting GGTA1 and CMAH with respect to gene editing efficiency in zygotes, and transferred electroporated embryos with the optimized gRNAs and Cas9 into recipient gilts. Next, we optimized the Cas9 protein concentration with respect to the gene editing efficiency when GGTA1, CMAH, and B4GALNT2 were targeted simultaneously, and generated gene-edited pigs using the optimized conditions. We achieved the one-step generation of GGTA1/CMAH double-edited pigs and GGTA1/CMAH/B4GALNT2 triple-edited pigs. Immunohistological analyses demonstrated the downregulation of xenoantigens; however, these multiple gene-edited pigs were genetic mosaics that failed to knock out some xenoantigens. Although mosaicism should be resolved, the electroporation technique could become a primary method for the one-step generation of multiple gene modifications in pigs aimed at improving pig-to-human xenotransplantation.
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16
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Lipofection-Mediated Introduction of CRISPR/Cas9 System into Porcine Oocytes and Embryos. Animals (Basel) 2021; 11:ani11020578. [PMID: 33672168 PMCID: PMC7926877 DOI: 10.3390/ani11020578] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2021] [Revised: 02/11/2021] [Accepted: 02/19/2021] [Indexed: 02/06/2023] Open
Abstract
Simple Summary Liposome-mediated gene transfer has become an alternative method for establishing a gene targeting framework, and the production of mutant animals may be feasible even in laboratories without specialized equipment. However, whether blastocyst genome editing can be performed by treatment with lipofection reagent, guide RNA, and Cas9, without performing electroporation or microinjection, remains unclear. In this study, we demonstrated that lipofection treatment successfully induced mutation into zygotes during in vitro fertilization and in embryos at the 2- and 4-cell stages. Although liposome-mediated gene editing is a feasible system for use with zona-pellucida-free oocytes/embryos, several challenges must be overcome. Abstract Liposome-mediated gene transfer has become an alternative method for establishing a gene targeting framework, and the production of mutant animals may be feasible even in laboratories without specialized equipment. However, how this system functions in mammalian oocytes and embryos remains unclear. The present study was conducted to clarify whether blastocyst genome editing can be performed by treatment with lipofection reagent, guide RNA, and Cas9 for 5 h without using electroporation or microinjection. A mosaic mutation was observed in blastocysts derived from zona pellucida (ZP)-free oocytes following lipofection treatment, regardless of the target genes. When lipofection treatment was performed after in vitro fertilization (IVF), no significant differences in the mutation rates or mutation efficiency were found between blastocysts derived from embryos treated at 24 and 29 h from the start of IVF. Only blastocysts from embryos exposed to lipofection treatment at 29 h after IVF contained biallelic mutant. Furthermore, there were no significant differences in the mutation rates or mutation efficiency between blastocysts derived from embryos at the 2- and 4-cell stages. This suggests that lipofection-mediated gene editing can be performed in ZP-free oocytes and ZP-free embryos; however, other factors affecting the system efficiency should be further investigated.
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17
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Niu D, Ma X, Yuan T, Niu Y, Xu Y, Sun Z, Ping Y, Li W, Zhang J, Wang T, Church GM. Porcine genome engineering for xenotransplantation. Adv Drug Deliv Rev 2021; 168:229-245. [PMID: 32275950 DOI: 10.1016/j.addr.2020.04.001] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2019] [Revised: 03/28/2020] [Accepted: 04/06/2020] [Indexed: 02/06/2023]
Abstract
The extreme shortage of human donor organs for treatment of patients with end-stage organ failures is well known. Xenotransplantation, which might provide unlimited organ supply, is a most promising strategy to solve this problem. Domestic pigs are regarded as ideal organ-source animals owing to similarity in anatomy, physiology and organ size to humans as well as high reproductive capacity and low maintenance cost. However, several barriers, which include immune rejection, inflammation and coagulative dysfunctions, as well as the cross-species transmission risk of porcine endogenous retrovirus, blocked the pig-to-human xenotransplantation. With the rapid development of genome engineering technologies and the potent immunosuppressive medications in recent years, these barriers could be eliminated through genetic modification of pig genome together with the administration of effective immunosuppressants. A number of candidate genes involved in the regulation of immune response, inflammation and coagulation have been explored to optimize porcine xenograft survival in non-human primate recipients. PERV inactivation in pigs has also been accomplished to firmly address the safety issue in pig-to-human xenotransplantation. Many encouraging preclinical milestones have been achieved with some organs surviving for years. Therefore, the clinical trials of some promising organs, such as islet, kidney and heart, are aimed to be launched in the near future.
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Affiliation(s)
- Dong Niu
- Key Laboratory of Applied Technology on Green-Eco-Healthy Animal Husbandry of Zhejiang Province, China-Australian Joint Laboratory for Animal Health Big Data Analytics, Zhejiang Provincial Engineering Laboratory for Animal Health Inspection & Internet Technology, College of Animal Science and Technology & College of Veterinary Medicine of Zhejiang A&F University, Hangzhou, P.R. China
| | - Xiang Ma
- Key Laboratory of Applied Technology on Green-Eco-Healthy Animal Husbandry of Zhejiang Province, China-Australian Joint Laboratory for Animal Health Big Data Analytics, Zhejiang Provincial Engineering Laboratory for Animal Health Inspection & Internet Technology, College of Animal Science and Technology & College of Veterinary Medicine of Zhejiang A&F University, Hangzhou, P.R. China
| | - Taoyan Yuan
- Institute of Animal Husbandry and Veterinary Science, Zhejiang Academy of Agricultural Sciences, Hangzhou, Zhejiang 310021, China
| | - Yifan Niu
- Nanjing Kgene Genetic Engineering Co., Ltd, Nanjing, Jiangsu 211300, China
| | - Yibin Xu
- College of Animal Sciences, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Zhongxin Sun
- Cosmetic & Plastic Surgery Department, Hangzhou First People's Hospital, Hangzhou, Zhejiang 310006, China
| | - Yuan Ping
- College of Pharmaceutical Sciences, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Weifen Li
- College of Animal Sciences, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Jufang Zhang
- Cosmetic & Plastic Surgery Department, Hangzhou First People's Hospital, Hangzhou, Zhejiang 310006, China.
| | - Tao Wang
- Nanjing Kgene Genetic Engineering Co., Ltd, Nanjing, Jiangsu 211300, China.
| | - George M Church
- Department of Genetics, Harvard Medical School, Boston, MA 02115, USA; Wyss Institute for Biologically Inspired Engineering, Harvard University, Cambridge, MA 02138, USA.
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18
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Miao D, Giassetti MI, Ciccarelli M, Lopez-Biladeau B, Oatley JM. Simplified pipelines for genetic engineering of mammalian embryos by CRISPR-Cas9 electroporation†. Biol Reprod 2020; 101:177-187. [PMID: 31095680 DOI: 10.1093/biolre/ioz075] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2018] [Revised: 02/18/2019] [Accepted: 04/25/2019] [Indexed: 02/07/2023] Open
Abstract
Gene editing technologies, such as CRISPR-Cas9, have important applications in mammalian embryos for generating novel animal models in biomedical research and lines of livestock with enhanced production traits. However, the lack of methods for efficient introduction of gene editing reagents into zygotes of various species and the need for surgical embryo transfer in mice have been technical barriers of widespread use. Here, we described methodologies that overcome these limitations for embryos of mice, cattle, and pigs. Using mutation of the Nanos2 gene as a readout, we refined electroporation parameters with preassembled sgRNA-Cas9 RNPs for zygotes of all three species without the need for zona pellucida dissolution that led to high-efficiency INDEL edits. In addition, we optimized culture conditions to support maturation from zygote to the multicellular stage for all three species that generates embryos ready for transfer to produce gene-edited animals. Moreover, for mice, we devised a nonsurgical embryo transfer method that yields offspring at an efficiency comparable to conventional surgical approaches. Collectively, outcomes of these studies provide simplified pipelines for CRISPR-Cas9-based gene editing that are applicable in a variety of mammalian species.
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Affiliation(s)
- Deqiang Miao
- Center for Reproductive Biology, School of Molecular Biosciences, College of Veterinary Medicine, Washington State University, Pullman, Washington, USA
| | - Mariana Ianello Giassetti
- Center for Reproductive Biology, School of Molecular Biosciences, College of Veterinary Medicine, Washington State University, Pullman, Washington, USA
| | - Michela Ciccarelli
- Center for Reproductive Biology, School of Molecular Biosciences, College of Veterinary Medicine, Washington State University, Pullman, Washington, USA
| | - Blanca Lopez-Biladeau
- Center for Reproductive Biology, School of Molecular Biosciences, College of Veterinary Medicine, Washington State University, Pullman, Washington, USA
| | - Jon M Oatley
- Center for Reproductive Biology, School of Molecular Biosciences, College of Veterinary Medicine, Washington State University, Pullman, Washington, USA
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19
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Tanihara F, Hirata M, Nguyen NT, Sawamoto O, Kikuchi T, Doi M, Otoi T. Efficient generation of GGTA1-deficient pigs by electroporation of the CRISPR/Cas9 system into in vitro-fertilized zygotes. BMC Biotechnol 2020; 20:40. [PMID: 32811500 PMCID: PMC7436961 DOI: 10.1186/s12896-020-00638-7] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2020] [Accepted: 08/10/2020] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND Xenoantigens are a major source of concern with regard to the success of interspecific xenografts. GGTA1 encodes α1,3-galactosyltransferase, which is essential for the biosynthesis of galactosyl-alpha 1,3-galactose, the major xenoantigen causing hyperacute rejection. GGTA1-modified pigs, therefore, are promising donors for pig-to-human xenotransplantation. In this study, we developed a method for the introduction of the CRISPR/Cas9 system into in vitro-fertilized porcine zygotes via electroporation to generate GGTA1-modified pigs. RESULTS We designed five guide RNAs (gRNAs) targeting distinct sites in GGTA1. After the introduction of the Cas9 protein with each gRNA via electroporation, the gene editing efficiency in blastocysts developed from zygotes was evaluated. The gRNA with the highest gene editing efficiency was used to generate GGTA1-edited pigs. Six piglets were delivered from two recipient gilts after the transfer of electroporated zygotes with the Cas9/gRNA complex. Deep sequencing analysis revealed that five out of six piglets carried a biallelic mutation in the targeted region of GGTA1, with no off-target events. Furthermore, staining with isolectin B4 confirmed deficient GGTA1 function in GGTA1 biallelic mutant piglets. CONCLUSIONS We established GGTA1-modified pigs with high efficiency by introducing a CRISPR/Cas9 system into zygotes via electroporation. Multiple gene modifications, including knock-ins of human genes, in porcine zygotes via electroporation may further improve the application of the technique in pig-to-human xenotransplantation.
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Affiliation(s)
- Fuminori Tanihara
- Laboratory of Animal Reproduction, Faculty of Bioscience and Bioindustry, Tokushima University, 2272-1 Ishii, Myozai-gun, Tokushima, 779-3233, Japan
| | - Maki Hirata
- Laboratory of Animal Reproduction, Faculty of Bioscience and Bioindustry, Tokushima University, 2272-1 Ishii, Myozai-gun, Tokushima, 779-3233, Japan.
| | - Nhien Thi Nguyen
- Laboratory of Animal Reproduction, Faculty of Bioscience and Bioindustry, Tokushima University, 2272-1 Ishii, Myozai-gun, Tokushima, 779-3233, Japan
| | - Osamu Sawamoto
- Research and Development Center, Otsuka Pharmaceutical Factory, Inc., 115 Muya-cho, Naruto, Tokushima, 772-8601, Japan
| | - Takeshi Kikuchi
- Research and Development Center, Otsuka Pharmaceutical Factory, Inc., 115 Muya-cho, Naruto, Tokushima, 772-8601, Japan
| | - Masako Doi
- Research and Development Center, Otsuka Pharmaceutical Factory, Inc., 115 Muya-cho, Naruto, Tokushima, 772-8601, Japan
| | - Takeshige Otoi
- Laboratory of Animal Reproduction, Faculty of Bioscience and Bioindustry, Tokushima University, 2272-1 Ishii, Myozai-gun, Tokushima, 779-3233, Japan
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20
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Hirata M, Wittayarat M, Namula Z, Le QA, Lin Q, Nguyen NT, Takebayashi K, Sato Y, Tanihara F, Otoi T. Evaluation of multiple gene targeting in porcine embryos by the CRISPR/Cas9 system using electroporation. Mol Biol Rep 2020; 47:5073-5079. [PMID: 32519310 DOI: 10.1007/s11033-020-05576-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2020] [Accepted: 06/05/2020] [Indexed: 12/12/2022]
Abstract
The CRISPR/Cas9 system now allows for unprecedented possibilities of genome editing. However, there are some limitations, including achieving efficient one-step multiple genome targeting to save costs, time, and ensure high quality. In the present study, we investigated the efficiency of one-step multiple gene modification by electroporation in porcine zygotes using pooled guide RNAs (gRNAs) targeting CMAH, GHR, GGTA1, and PDX1. We first selected the best-performing gRNA from three different designs for each gene based on the effect on embryo development and mutation efficiency. The three gRNAs showed equivalent effects on the rates of blastocyst formation in each targeted gene; however, gRNAs CMAH #2, GHR #3, GGTA1 #3, and PDX1 #3 showed the highest biallelic mutation rate, although the total mutation rate of PDX1 #3 was significantly lower than that of PDX1 #1. Therefore, CMAH #2, GHR #3, GGTA1 #3, and PDX1 #1 were used as a mixture in electroporation to further clarify whether multiple genes can be targeted simultaneously. Individual sequencing of 43 blastocysts at the target sites of each gene showed mutations in one and two target genes in twenty-four (55.8%) and nine (20.9%) blastocysts, respectively. No mutation was detected in any target gene in ten (23.3%) blastocysts and no blastocysts had a mutation in three or more target genes. These results indicate that electroporation could effectively deliver multiple gRNAs and Cas9 protein into porcine zygotes to target multiple genes in a one-step process. However, the technique requires further development to increase the success rate of multiple gene modification.
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Affiliation(s)
- Maki Hirata
- Faculty of Bioscience and Bioindustry, Tokushima University, 2272-1 Ishii, Myozai-gun, Tokushima, 779-3233, Japan
| | - Manita Wittayarat
- Faculty of Veterinary Science, Prince of Songkla University, Songkhla, Thailand
| | - Zhao Namula
- Faculty of Veterinary Science, Guangdong Ocean University, Zhanjiang, China
| | - Quynh Anh Le
- Faculty of Bioscience and Bioindustry, Tokushima University, 2272-1 Ishii, Myozai-gun, Tokushima, 779-3233, Japan
| | - Qingyi Lin
- Faculty of Bioscience and Bioindustry, Tokushima University, 2272-1 Ishii, Myozai-gun, Tokushima, 779-3233, Japan
| | - Nhien Thi Nguyen
- Faculty of Bioscience and Bioindustry, Tokushima University, 2272-1 Ishii, Myozai-gun, Tokushima, 779-3233, Japan
| | - Koki Takebayashi
- Faculty of Bioscience and Bioindustry, Tokushima University, 2272-1 Ishii, Myozai-gun, Tokushima, 779-3233, Japan
| | - Yoko Sato
- School of Biological Science, Tokai University, Sapporo, Japan
| | - Fuminori Tanihara
- Faculty of Bioscience and Bioindustry, Tokushima University, 2272-1 Ishii, Myozai-gun, Tokushima, 779-3233, Japan.
| | - Takeshige Otoi
- Faculty of Bioscience and Bioindustry, Tokushima University, 2272-1 Ishii, Myozai-gun, Tokushima, 779-3233, Japan
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21
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Livestock Gene Editing by One-step Embryo Manipulation. J Equine Vet Sci 2020; 89:103025. [PMID: 32563448 DOI: 10.1016/j.jevs.2020.103025] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2020] [Revised: 04/06/2020] [Accepted: 04/07/2020] [Indexed: 12/11/2022]
Abstract
The breakthrough and rapid advance of clustered regularly interspaced short palindromic repeat (CRISPR)/CRISPR-associated protein 9 (Cas9) technology has enabled the efficient generation of gene-edited animals by one-step embryo manipulation. Clustered regularly interspaced short palindromic repeat/CRISPR-associated protein 9 delivery to the livestock embryos has been typically achieved by intracytoplasmic microinjection; however, recent studies show that electroporation may be a reliable, efficient, and practical method for CRISPR/Cas9 delivery. The source of embryos used to generate gene-edited animals varies from in vivo to in vitro produced, depending mostly on the species of interest. In addition, different Cas9 and gRNA reagents can be used for embryo editing, ranging from Cas9-coding plasmid or messenger RNA to Cas9 recombinant protein, which can be combined with in vitro transcribed or synthetic guide RNAs. Mosaicism is reported as one of the main problems with generation of animals by embryo editing. On the other hand, off-target mutations are rarely found in livestock derived from one-step editing. In this review, we discussed these and other aspects of generating gene-edited animals by single-step embryo manipulation.
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Hirata M, Wittayarat M, Hirano T, Nguyen NT, Le QA, Namula Z, Fahrudin M, Tanihara F, Otoi T. The Relationship between Embryonic Development and the Efficiency of Target Mutations in Porcine Endogenous Retroviruses (PERVs) Pol Genes in Porcine Embryos. Animals (Basel) 2019; 9:ani9090593. [PMID: 31443357 PMCID: PMC6770129 DOI: 10.3390/ani9090593] [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: 05/27/2019] [Revised: 07/30/2019] [Accepted: 08/19/2019] [Indexed: 12/17/2022] Open
Abstract
Porcine endogenous retrovirus (PERV) is a provirus found in the pig genome that may act as an infectious pathogen in humans who receive pig organ xenotransplantation. Inactivation of the PERV pol gene in porcine cells reportedly affects cell growth. Therefore, the mutation of PERV pol gene in porcine embryos using genome editing may affect the embryonic development. The present study was carried out to investigate the relationship between the mutation of the PERV pol gene in porcine embryos and their development. We introduced, either alone or in combination, three different gRNAs (gRNA1, 2, and 3) into porcine zygotes by genome editing using electroporation of the Cas9 protein (GEEP) system. All three gRNAs targeted the PERV pol gene, and we assessed their effects on porcine embryonic development. Our results showed that the blastocyst formation rates of zygotes electroporated with gRNA3-alone and in combination-were significantly lower (p < 0.05) than those of zygotes electroporated with gRNA1. The mutation rates assessed by the PERV pol gene target site sequencing in individual blastocysts and pooled embryos at the 2-to-8-cell stage did not differ among the three gRNAs. However, the frequency of indel mutations in mutant embryos at the 2-to-8-cell stage trended higher in the embryos electroporated with gRNA3 alone and in combination. Embryonic development may be affected by gRNAs that induce high-frequency indel mutations.
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Affiliation(s)
- Maki Hirata
- Faculty of Bioscience and Bioindustry, Tokushima University, Myozai-gun, Tokushima 7793233, Japan
| | - Manita Wittayarat
- Faculty of Veterinary Science, Prince of Songkla University, Hat Yai, Songkhla 90110, Thailand
| | - Takayuki Hirano
- Faculty of Bioscience and Bioindustry, Tokushima University, Myozai-gun, Tokushima 7793233, Japan
| | - Nhien Thi Nguyen
- Faculty of Bioscience and Bioindustry, Tokushima University, Myozai-gun, Tokushima 7793233, Japan
| | - Quynh Anh Le
- Faculty of Bioscience and Bioindustry, Tokushima University, Myozai-gun, Tokushima 7793233, Japan
| | - Zhao Namula
- Faculty of Veterinary Science, Guangdong Ocean University, Zhanjiang, Guangdong 524005, China
| | - Mokhamad Fahrudin
- Faculty of Veterinary Science, Bogor Agricultural University, Dramaga, Bogor 16680, Indonesia
| | - Fuminori Tanihara
- Faculty of Bioscience and Bioindustry, Tokushima University, Myozai-gun, Tokushima 7793233, Japan.
| | - Takeshige Otoi
- Faculty of Bioscience and Bioindustry, Tokushima University, Myozai-gun, Tokushima 7793233, Japan
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Namula Z, Wittayarat M, Hirata M, Hirano T, Nguyen NT, Le QA, Fahrudin M, Tanihara F, Otoi T. Genome mutation after the introduction of the gene editing by electroporation of Cas9 protein (GEEP) system into bovine putative zygotes. In Vitro Cell Dev Biol Anim 2019; 55:598-603. [PMID: 31297696 DOI: 10.1007/s11626-019-00385-w] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2019] [Accepted: 07/01/2019] [Indexed: 12/21/2022]
Abstract
The present study was designed to investigate the effects of voltage strength on embryonic developmental rate and mutation efficiency in bovine putative zygotes during electroporation with the CRISPR/Cas9 system to target the MSTN gene at different time points after insemination. Results showed that there was no significant interaction between electroporation time and voltage strength on the embryonic cleavage and blastocyst formation rates. However, increasing the voltage strength to 20 V/mm to electroporate the zygotes at 10 h after the start of insemination yielded significantly lower blastocyst formation rates (P < 0.05) than those of the 10-V/mm electroporated zygotes. Mutation efficiency was then assessed in individual blastocysts by DNA sequence analysis of the target sites in the MSTN gene. A positive correlation between mutation rate and voltage strength was observed. The mutation efficiency in mutant blastocysts was significantly higher in the zygotes electroporated with 20 V/mm at 10 h after the start of insemination (P < 0.05) than in the zygotes electroporated at 15 h, irrespective of the voltage strength. We also noted that a certain number of blastocysts from zygotes that were electroporated with more than 15 V/mm at 10 h (4.8-16.7%) and 20 V/mm at 15 h (4.8%) were biallelic mutants. Our results suggest that the voltage strength during electroporation as well as electroporation time certainly have effects on the embryonic developmental rate and mutation efficiency in bovine putative zygotes.
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Affiliation(s)
- Zhao Namula
- Faculty of Veterinary Science, Guangdong Ocean University, Zhanjiang, China
| | - Manita Wittayarat
- Faculty of Veterinary Science, Prince of Songkla University, Songkhla, Thailand
| | - Maki Hirata
- Faculty of Veterinary Science, Guangdong Ocean University, Zhanjiang, China.,Laboratory of Animal Reproduction, Faculty of Bioscience and Bioindustry, Tokushima University, 2272-1 Ishii, Myozai-gun, Tokushima, 779-3233, Japan
| | - Takayuki Hirano
- Laboratory of Animal Reproduction, Faculty of Bioscience and Bioindustry, Tokushima University, 2272-1 Ishii, Myozai-gun, Tokushima, 779-3233, Japan
| | - Nhien Thi Nguyen
- Laboratory of Animal Reproduction, Faculty of Bioscience and Bioindustry, Tokushima University, 2272-1 Ishii, Myozai-gun, Tokushima, 779-3233, Japan
| | - Quynh Anh Le
- Laboratory of Animal Reproduction, Faculty of Bioscience and Bioindustry, Tokushima University, 2272-1 Ishii, Myozai-gun, Tokushima, 779-3233, Japan
| | - Mokhamad Fahrudin
- Faculty of Veterinary Science, Bogor Agricultural University, Bogor, Indonesia
| | - Fuminori Tanihara
- Faculty of Veterinary Science, Guangdong Ocean University, Zhanjiang, China. .,Laboratory of Animal Reproduction, Faculty of Bioscience and Bioindustry, Tokushima University, 2272-1 Ishii, Myozai-gun, Tokushima, 779-3233, Japan.
| | - Takeshige Otoi
- Faculty of Veterinary Science, Guangdong Ocean University, Zhanjiang, China.,Laboratory of Animal Reproduction, Faculty of Bioscience and Bioindustry, Tokushima University, 2272-1 Ishii, Myozai-gun, Tokushima, 779-3233, Japan
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24
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Tanihara F, Hirata M, Morikawa S, Nguyen NT, LE QA, Hirano T, Fukumi Y, Abe T, Otoi T. The effects of electroporation on viability and quality of in vivo-derived bovine blastocysts. J Reprod Dev 2019; 65:475-479. [PMID: 31178553 PMCID: PMC6815737 DOI: 10.1262/jrd.2019-049] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
The introduction of exogenous molecules into embryos is required for analyses of molecular dynamics and specific gene functions during early embryonic development. Electroporation is an
effective method to transport exogenous molecules into cells, but is rarely used in bovine embryos. First, we evaluated the viability of in vivo-derived bovine blastocysts
after electroporation with fluorescein (FAM) labeled-oligonucleotides with varying pulse numbers (3, 5, 7, and 10), while keeping the pulse duration at 1 msec and the electric field of 20
V/mm. Next, we examined the effects of zona pellucida status on blastocyst quality after electroporation, by comparing the average diameter of blastocysts before and after electroporation
using blastocysts with intact zona pellucida and hatching/hatched blastocysts. Electroporation successfully introduced exogenous molecules into in vivo-derived bovine
blastocysts without loss of viability. Moreover, the status of the zona pellucida may be associated with the quality of blastocysts after electroporation.
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Affiliation(s)
- Fuminori Tanihara
- Laboratory of Animal Reproduction, Faculty of Bioscience and Bioindustry, Tokushima University, Tokushima 779-3233, Japan
| | - Maki Hirata
- Laboratory of Animal Reproduction, Faculty of Bioscience and Bioindustry, Tokushima University, Tokushima 779-3233, Japan
| | - Shigeki Morikawa
- Tokushima Prefectural Livestock Research Institute, Tokushima 779-3233, Japan
| | - Nhien Thi Nguyen
- Laboratory of Animal Reproduction, Faculty of Bioscience and Bioindustry, Tokushima University, Tokushima 779-3233, Japan
| | - Quynh Anh LE
- Laboratory of Animal Reproduction, Faculty of Bioscience and Bioindustry, Tokushima University, Tokushima 779-3233, Japan
| | - Takayuki Hirano
- Laboratory of Animal Reproduction, Faculty of Bioscience and Bioindustry, Tokushima University, Tokushima 779-3233, Japan
| | - Yoshiyuki Fukumi
- Tokushima Prefectural Livestock Research Institute, Tokushima 779-3233, Japan
| | - Toshiaki Abe
- Tokushima Prefectural Livestock Research Institute, Tokushima 779-3233, Japan
| | - Takeshige Otoi
- Laboratory of Animal Reproduction, Faculty of Bioscience and Bioindustry, Tokushima University, Tokushima 779-3233, Japan
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Hirata M, Tanihara F, Wittayarat M, Hirano T, Nguyen NT, Le QA, Namula Z, Nii M, Otoi T. Genome mutation after introduction of the gene editing by electroporation of Cas9 protein (GEEP) system in matured oocytes and putative zygotes. In Vitro Cell Dev Biol Anim 2019; 55:237-242. [PMID: 30820813 DOI: 10.1007/s11626-019-00338-3] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2018] [Accepted: 02/13/2019] [Indexed: 11/30/2022]
Abstract
The application of CRISPR/Cas9 strategy promises to rapidly increase the production of genetically engineered animals since it yields stably integrated transgenes. In the present study, we investigated the efficiency of target mutations after electroporation with the CRISPR/Cas9 system using sgRNAs to target the MSTN or FGF10 genes in porcine-matured oocytes and putative zygotes. Effects of pulse number (3-7 pulse repetitions) during electroporation on the embryonic development and mutation efficiency were also investigated. Our results showed that the cleavage rate of matured oocytes with electroporation treatment significantly decreased as compared with electroporated putative zygotes (p < 0.05). Moreover, the rates of blastocyst formation from oocytes/zygotes electroporated with more than 5 pulses decreased. Mutation efficiency was then assessed after sequencing the target sites in individual blastocysts derived from oocytes/zygotes electroporated by 3 and 5 pulses. No bi-allelic mutations in all examined blastocysts were observed in this study. There were no differences in the mutation rates (50-60%) between blastocysts derived from matured oocytes electroporated by 3 and 5 pulses, irrespective of targeting gene. In the targeting MSTN gene, however, the mutation rate (12.5%) of blastocysts derived from putative zygotes electroporated by 3 pulses tended to be lower than that (60%) from 5-pulsed electroporated putative zygotes. These data indicate that the type of eggs may influence not only their development after electroporation treatment but also the mutation rate in the resulting blastocysts.
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Affiliation(s)
- Maki Hirata
- Faculty of Bioscience and Bioindustry, Tokushima University, Tokushima, Japan
| | - Fuminori Tanihara
- Faculty of Bioscience and Bioindustry, Tokushima University, Tokushima, Japan.
| | - Manita Wittayarat
- Faculty of Veterinary Science, Prince of Songkla University, Songkhla, Thailand
| | - Takayuki Hirano
- Faculty of Bioscience and Bioindustry, Tokushima University, Tokushima, Japan
| | - Nhien Thi Nguyen
- Faculty of Bioscience and Bioindustry, Tokushima University, Tokushima, Japan
| | - Quynh Anh Le
- Faculty of Bioscience and Bioindustry, Tokushima University, Tokushima, Japan
| | - Zhao Namula
- Faculty of Veterinary Science, Guangdong Ocean University, Zhanjiang, China
| | - Masahiro Nii
- Tokushima Prefectural Livestock Research Institute, Tokushima, Japan
| | - Takeshige Otoi
- Faculty of Bioscience and Bioindustry, Tokushima University, Tokushima, Japan
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