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Yu T, Zhang C, Song W, Zhao X, Cheng Y, Liu J, Su J. Single-cell RNA-seq and single-cell bisulfite-sequencing reveal insights into yak preimplantation embryogenesis. J Biol Chem 2024; 300:105562. [PMID: 38097189 PMCID: PMC10821408 DOI: 10.1016/j.jbc.2023.105562] [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: 03/24/2023] [Revised: 11/17/2023] [Accepted: 12/03/2023] [Indexed: 01/13/2024] Open
Abstract
Extensive epigenetic reprogramming occurs during preimplantation embryonic development. However, the impact of DNA methylation in plateau yak preimplantation embryos and how epigenetic reprogramming contributes to transcriptional regulatory networks are unclear. In this study, we quantified gene expression and DNA methylation in oocytes and a series of yak embryos at different developmental stages and at single-cell resolution using single-cell bisulfite-sequencing and RNA-seq. We characterized embryonic genome activation and maternal transcript degradation and mapped epigenetic reprogramming events critical for embryonic development. Through cross-species transcriptome analysis, we identified 31 conserved maternal hub genes and 39 conserved zygotic hub genes, including SIN3A, PRC1, HDAC1/2, and HSPD1. Notably, by combining single-cell DNA methylation and transcriptome analysis, we identified 43 candidate methylation driver genes, such as AURKA, NUSAP1, CENPF, and PLK1, that may be associated with embryonic development. Finally, using functional approaches, we further determined that the epigenetic modifications associated with the histone deacetylases HDAC1/2 are essential for embryonic development and that the deubiquitinating enzyme USP7 may affect embryonic development by regulating DNA methylation. Our data represent an extensive resource on the transcriptional dynamics of yak embryonic development and DNA methylation remodeling, and provide new insights into strategies for the conservation of germplasm resources, as well as a better understanding of mammalian early embryonic development that can be applied to investigate the causes of early developmental disorders.
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Affiliation(s)
- Tong Yu
- Key Laboratory of Animal Biotechnology of the Ministry of Agriculture, College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, China
| | - Chengtu Zhang
- Academician Zhang Yong Innovation Center, Xining Animal Disease Control Center, Xining, Qinghai, China
| | - Weijia Song
- Key Laboratory of Animal Biotechnology of the Ministry of Agriculture, College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, China
| | - Xinyi Zhao
- Key Laboratory of Animal Biotechnology of the Ministry of Agriculture, College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, China
| | - Yuyao Cheng
- Key Laboratory of Animal Biotechnology of the Ministry of Agriculture, College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, China
| | - Jun Liu
- Key Laboratory of Animal Biotechnology of the Ministry of Agriculture, College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, China.
| | - Jianmin Su
- Key Laboratory of Animal Biotechnology of the Ministry of Agriculture, College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, China.
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Cattle breed affects in vitro embryo production in a large-scale commercial program on dairy farms. Livest Sci 2020. [DOI: 10.1016/j.livsci.2020.104135] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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Yang RF, Xiong XR, Zi XD. Effect of cysteine, insulin-like growth factor-1 and epidermis growth factor during in vitro oocyte maturation and in vitro culture of yak-cattle crossbred embryos. JOURNAL OF APPLIED ANIMAL RESEARCH 2019. [DOI: 10.1080/09712119.2019.1663353] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Affiliation(s)
- Rao-fen Yang
- Key-Laboratory for Animal Science of State Ethnic Affairs Commission, Southwest Minzu University, Chengdu, People’s Republic of China
| | - Xian-rong Xiong
- Key-Laboratory for Animal Science of State Ethnic Affairs Commission, Southwest Minzu University, Chengdu, People’s Republic of China
| | - Xiang-dong Zi
- Key-Laboratory for Animal Science of State Ethnic Affairs Commission, Southwest Minzu University, Chengdu, People’s Republic of China
- College of Life Science and Technology, Southwest University for Nationalities, Chengdu, People’s Republic of China
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Transcriptional profiles of crossbred embryos derived from yak oocytes in vitro fertilized with cattle sperm. Sci Rep 2018; 8:11571. [PMID: 30069024 PMCID: PMC6070518 DOI: 10.1038/s41598-018-29912-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2018] [Accepted: 07/20/2018] [Indexed: 12/24/2022] Open
Abstract
During mammalian pre-implantation embryonic development, dramatic and orchestrated changes occur in gene transcription. Pregnancy rates were low when yak females were crossbred with cattle breeds, but few studies exist to describe the unique molecular network regulation behind the pre-implantation development of these embryos. We determined the transcriptomes of crossbred embryos derived from yak oocytes in vitro fertilized with Jersey sperm using Illumina RNA-seq for the first time in this study. Embryos were sampled at the 2-, 4-, and 8-cell, morula and blastocyst stages. The results showed that in total, 291.9 million short reads were generated from the five libraries of 2-, 4-, and 8-cell, morula and blastocyst stages, with 276.2 million high-quality reads selected for further analysis. Eighty to 91% of the clean reads were aligned against the yak reference genome. A total of 19,072 transcripts were identified in five libraries, of which 7,785 transcripts were co-expressed in each stage and 2,013 transcripts were stage-specific. When a |log2 ratio| ≥1 and q-value ≤ 0.05 were set as thresholds for identifying differentially expressed genes (DEGs), we detected a total of 3,690 to 10,298 DEGs between any two consecutive stages. Based on the results of GO and KEGG enrichment, some of these DEGs potentially play an important role in regulating pre-implantation development, but they are most likely stage-specific. There were 2,960, 7,287, 6,420, 7,724 and 10,417 DEGs in 2-, 4-, 8-cell, morula and blastocyst stages between the crossbred embryos and purebred embryos of the yak, respectively, leading to a large difference in GO terms and pathways. In conclusion, we sequenced transcriptomes of in vitro-produced crossbred embryos of yak and cattle during pre-implantation and provided comprehensive examinations of gene activities. These will be helpful for development of assisted reproductive technology and better understanding the early maternal-fetal or maternal-embryonic dialog in inter-species crossbreeding.
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Jia Y, Yang X, Zhang C, Yang S, Li M, Xu W, Ji Q, Jiang H. Cryosurvival and pregnancy rates: One-step protocol for freezing-thawing Shangri-la Yak (Bos grunniens) Embryos. Reprod Domest Anim 2018; 53:1168-1175. [PMID: 29962058 DOI: 10.1111/rda.13222] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2018] [Revised: 05/02/2018] [Accepted: 05/16/2018] [Indexed: 01/07/2023]
Abstract
The yak is one of the most important and economically useful animals for highlanders. The decline in the yak population requires effective measures for the conservation and multiplication of elite germplasm. A standardized protocol will simplify the freezing and warming of yak embryos in straw and facilitate embryo transfer. In this work, we investigated a one-step protocol that uses a stable basal medium, which comprised a warming medium (1.08 M sucrose) and a freezing medium (EFS40). We also assessed the effects of the new transfer method on embryo survival. A total of 145 yak frozen embryos were thawed in a standard medium system. The one-step protocol led to a high recovery percentage (84.93) of yak embryos that survived vitrification and warming. The in vitro survival rates of these embryos significantly different from those of embryos frozen-thawed via the conventional method. The 95 embryos frozen-thawed via our one-step protocol were then implanted in selected recipients. Thirty-six singleton pregnancies were established. In conclusion, the proposed one-step method is a simple, safe, and standardized freezing-thawing protocol that ensures embryo survival and quality under field conditions. This study establishes new possibilities for the widespread use of embryo transfer in yaks.
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Affiliation(s)
- Yinhai Jia
- College of Animal Science and Technology, Guangxi University, Nanning, China
| | - Xiurong Yang
- College of Animal Science and Technology, Guangxi University, Nanning, China
| | - Chengfu Zhang
- Tibet Academy of Agricultural and Animal Husbandry Sciences, Institute of Husbandry and Pharmaceutical Science, Lhasa, China
| | - Shangzhi Yang
- Shangri-la Zanglong Biological Development Co., Ltd., Di qing, China
| | - Ming Li
- Guangxi Autonomous Region Livestock Breed Improvement Station, Nanning, China
| | - Wenwen Xu
- College of Animal Science and Technology, Guangxi University, Nanning, China
| | - Qiumei Ji
- Tibet Academy of Agricultural and Animal Husbandry Sciences, Institute of Husbandry and Pharmaceutical Science, Lhasa, China
| | - Hesheng Jiang
- College of Animal Science and Technology, Guangxi University, Nanning, China
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Zi XD, Luo B, Xia W, Zheng YC, Xiong XR, Li J, Zhong JC, Zhu JJ, Zhang ZF. Characterization of transcriptional complexity during pre-implantation development of the yak (Bos grunniens) using RNA-Seq. Reprod Domest Anim 2018; 53:759-768. [PMID: 29582471 DOI: 10.1111/rda.13167] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2017] [Accepted: 02/13/2018] [Indexed: 12/18/2022]
Abstract
The objective of this study was to investigate the mechanism that regulates pre-implantation development of the yak (Bos grunniens). We determined the transcriptomes of in vitro-produced yak embryos at two-cell, four-cell, eight-cell stages, and morula and blastocyst using the Illumina RNA-seq for the first time. We obtained 47.36-50.86 million clean reads for each stage, of which, 85.65%-90.02% reads were covered in the reference genome. A total of 17,368 genes were expressed during the two-cell stage to blastocyst of the yak, of which 7,236 genes were co-expressed at all stages, whereas 10,132 genes were stage-specific expression. Transcripts from 9,827 to 14,893 different genes were detected in various developmental stages. When |log2 ratio| ≥ 1 and q-value <0.05 were set as thresholds for identifying differentially expressed genes (DEGs), we detected a total of 6,922-10,555 DEGs between any two consecutive stages. The GO distributions of these DEGs were classified into three categories: biological processes (23 terms), cellular components (22 terms) and molecular functions (22 terms). Pathway analysis revealed 310 pathways of the DEGs that were operative in early pre-implantation yak development, of which 32 were the significantly enriched pathways. In conclusion, this is the first report to investigate the mechanism that regulates yak embryonic development using high-throughput sequencing, which provides a comprehensive framework of transcriptome landscapes of yak pre-implantation embryos.
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Affiliation(s)
- X-D Zi
- Key-Laboratory for Animal Science of State Ethnic Affairs Commission, Southwest University for Nationalities, Chengdu, China
| | - B Luo
- Key-Laboratory for Animal Science of State Ethnic Affairs Commission, Southwest University for Nationalities, Chengdu, China
| | - W Xia
- Key-Laboratory for Animal Science of State Ethnic Affairs Commission, Southwest University for Nationalities, Chengdu, China
| | - Y-C Zheng
- Key-Laboratory for Modern Biotechnology of State Ethnic Affairs Commission, Southwest University for Nationalities, Chengdu, China
| | - X-R Xiong
- Key-Laboratory for Animal Science of State Ethnic Affairs Commission, Southwest University for Nationalities, Chengdu, China
| | - J Li
- Key-Laboratory for Animal Science of State Ethnic Affairs Commission, Southwest University for Nationalities, Chengdu, China
| | - J-C Zhong
- Institute of Qinghai-Tibetan Plateau, Southwest University for Nationalities, Chengdu, China
| | - J-J Zhu
- Institute of Qinghai-Tibetan Plateau, Southwest University for Nationalities, Chengdu, China
| | - Z-F Zhang
- Key-Laboratory for Animal Science of State Ethnic Affairs Commission, Southwest University for Nationalities, Chengdu, China
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Paternal breed effects on expression of IGF-II, BAK1 and BCL2-L1 in bovine preimplantation embryos. ZYGOTE 2014; 23:712-21. [PMID: 25181591 DOI: 10.1017/s0967199414000367] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The effects of the paternal breed on early embryo and later pre- and postnatal development are well documented. Several recent studies have suggested that such paternal effects may be mediated by the paternally induced epigenetic modifications during early embryogenesis. The objective of this study was to investigate the effects of the paternal breed on the early embryonic development and relative expression of the maternally imprinted gene, IGF-II, and the apoptosis-related genes BAK1 and BCL2-L1 in in vitro produced (IVP) bovine embryos derived from two unrelated paternal breeds (Holstein and Brown Swiss). The degree of correlation of IGF-II expression pattern with embryo developmental competence and apoptosis-related genes was also investigated. The relative abundance of IGF-II, BCL2-L1 and BAK1 transcripts in day 8 embryos was measured by quantitative reverse-transcription polymerase chain reaction using the comparative Cp method. Our data revealed that the paternal breed did not influence cleavage rate, blastocyst rate and relative abundance of IGF-II, BAK1 and BCL2-L1 in day 8 blastocysts (P > 0.05). Nevertheless, IGF-II expression levels were highly correlated with embryonic developmental competence (r = 0.66, P < 0.1), relative expression of BCL2-L1 (r = 0.72, P < 0.05) and ratio of BCL2-L1/BAK1 (r = 0.78, P < 0.05). In conclusion, our data show that IGF-II, BCL2-L1 and BAK1 expression is not related to the chosen combination of paternal breed, but that IGF-II expression is correlated with embryonic viability and apoptosis-related gene expression.
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Cloning of cDNAs for H1F0, TOP1, CLTA and CDK1 and the effects of cryopreservation on the expression of their mRNA transcripts in yak (Bos grunniens) oocytes. Cryobiology 2014; 69:55-60. [DOI: 10.1016/j.cryobiol.2014.05.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2013] [Revised: 04/06/2014] [Accepted: 05/08/2014] [Indexed: 11/23/2022]
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Xiao X, Zi XD, Niu HR, Xiong XR, Zhong JC, Li J, Wang L, Wang Y. Effect of addition of FSH, LH and proteasome inhibitor MG132 to in vitro maturation medium on the developmental competence of yak (Bos grunniens) oocytes. Reprod Biol Endocrinol 2014; 12:30. [PMID: 24754924 PMCID: PMC3998235 DOI: 10.1186/1477-7827-12-30] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/20/2014] [Accepted: 04/14/2014] [Indexed: 01/17/2023] Open
Abstract
BACKGROUND The competence for embryonic development after IVF is low in the yak, therefore, we investigated the effects of supplementation of FSH, LH and the proteasome inhibitor MG132 in IVM media on yak oocyte competence for development after IVF. METHODS In Experiment 1, yak cumulus-oocyte complexes (COCs) were in vitro matured (IVM) in TCM-199 with 20% fetal calf serum (FCS), 1 microg/mL estradiol-17beta, and different combinations of LH (50 or 100 IU/mL) and FSH (0, 1, 5, 10 microg/mL) at 38.6 degrees C, 5% CO2 in air for 24 h. Matured oocytes were exposed to frozen-thawed, heparin-capacitated yak sperm. Presumptive zygotes were cultured in SOF medium containing 6 mg/ml BSA, 0.5 mg/mL myoinositol, 3% (v/v) essential amino acids, 1% nonessential amino acids and 100 μg/mL L-glutamine (48 h, 38.5 degrees C, 5% CO2, 5% O2, and 90% N2). In Experiment 2, cumulus cells were collected at the end of IVM to determine FSHR and LHR mRNA expression by real-time PCR. In Experiment 3 and 4, COCs were cultured in the presence or absence of the proteasomal inhibitor MG132 from either 0-6 h or 18-24 h after initiation of maturation. RESULTS The optimum concentration of FSH and LH in IVM media was 5 microg/mL FSH and 50 IU/mL LH which resulted in the greatest cleavage (79.1%) and blastocyst rates (16.1%). Both FSHR and LHR mRNA were detected in yak cumulus cells after IVM. Treatment with MG132 early in maturation reduced (P<0.05) cleavage and blastocyst rates. Conversely, treatment with MG132 late in maturation improved (P<0.05) blastocyst rate. Optimal results with MG132 were achieved at a concentration of 10 microM. CONCLUSIONS An optimum concentration of FSH and LH in IVM medium, and treatment with MG132 late in maturation can improve yak oocytes competence for development after IVF.
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Affiliation(s)
- Xiao Xiao
- College of Life Science and Technology, Southwest University for Nationalities, Chengdu 610041, People’s Republic of China
| | - Xiang-Dong Zi
- College of Life Science and Technology, Southwest University for Nationalities, Chengdu 610041, People’s Republic of China
| | - Hui-Ran Niu
- College of Life Science and Technology, Southwest University for Nationalities, Chengdu 610041, People’s Republic of China
| | - Xian-Rong Xiong
- College of Life Science and Technology, Southwest University for Nationalities, Chengdu 610041, People’s Republic of China
| | - Jin-Cheng Zhong
- College of Tibetan Plateau Research, Southwest University for Nationalities, Chengdu 610041, People’s Republic of China
| | - Jian Li
- College of Tibetan Plateau Research, Southwest University for Nationalities, Chengdu 610041, People’s Republic of China
| | - Li Wang
- College of Life Science and Technology, Southwest University for Nationalities, Chengdu 610041, People’s Republic of China
| | - Yong Wang
- College of Tibetan Plateau Research, Southwest University for Nationalities, Chengdu 610041, People’s Republic of China
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Niu HR, Zi XD, Xiao X, Xiong XR, Zhong JC, Li J, Wang L, Wang Y. Developmental competence of frozen-thawed yak (Bos grunniens) oocytes followed by in vitro maturation and fertilization. Cryobiology 2014; 68:152-4. [DOI: 10.1016/j.cryobiol.2014.01.012] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2013] [Revised: 12/18/2013] [Accepted: 01/14/2014] [Indexed: 12/24/2022]
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Chatiza FP, Bartels P, Nedambale TL, Wagenaar GM. Sperm-egg interaction and functional assessment of springbok, impala and blesbok cauda epididymal spermatozoa using a domestic cattle in vitro fertilization system. Anim Reprod Sci 2013; 143:8-18. [PMID: 24284137 DOI: 10.1016/j.anireprosci.2013.11.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2013] [Revised: 09/23/2013] [Accepted: 11/01/2013] [Indexed: 11/26/2022]
Abstract
The study assesses the possibility to estimate the potential fertility of post-thawed antelope (Antidorcas marsupialis), impala (Aepyceros melampus) and blesbok (Damaliscus dorcus phillipsi) epididymal sperm using homologous and heterologous IVF and the functioning of cattle IVF system to produce antelope embryos. Cauda epididymal sperm were collected from the antelope and cryopreserved under field conditions. In vitro matured domestic cow, blesbok and springbok oocytes were co-incubated in modified-Tyrode Lactate (m-TL) IVF media with springbok, impala and blesbok sperm for heterologous IVF and springbok and blesbok sperm for homologous IVF. A group of presumptive zygotes from each treatment were examined for sperm penetration and male pronuclear formation after 18h and the remainder were cultured and evaluated for embryo cleavage 22h later. The study shows that Modified Tyrode Lactate in vitro fertilization media supports survivability, capacitation and hyperactivation of springbok, impala and blesbok sperm. Springbok, impala and blesbok post-thawed epididymal spermatozoa are capable of fertilizing domestic cow oocytes under conditions that support domestic cattle IVF. Penetration, male pronuclear formation and embryo cleavage did not differ (p>0.05) between cow oocytes inseminated with sperm from springbok, impala or blesbok however these parameters were higher (p<0.05) for oocytes inseminated with bull sperm. Modified Tyrode Lactate IVF media supported homologous fertilization and embryo development in springbok and blesbok however did not support blastocyst development. These findings suggest that cattle provide a useful model for evaluating springbok, impala and blesbok post-thawed cauda epididymal sperm functionality. Domestic cattle embryo culture conditions need to be modified to promote blastosyst development in these antelope species. Such research provides an important tool in assisted reproductive technology development when high biological value material is utilized for wild species recovery plans.
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Affiliation(s)
- F P Chatiza
- University of Johannesburg, Department of Zoology, PO Box 524, Auckland Park, Johannesburg 2006, South Africa.
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Huang L, Zi XD, Xu HW. Strategy for embryo sex identification in the yak (Bos grunniens) by simultaneous amplification of theSRYandbHBBgenes. JOURNAL OF APPLIED ANIMAL RESEARCH 2012. [DOI: 10.1080/09712119.2011.645040] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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13
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Seaby RP, Mackie P, King WA, Mastromonaco GF. Investigation into developmental potential and nuclear/mitochondrial function in early wood and plains bison hybrid embryos. Reprod Domest Anim 2011; 47:644-54. [PMID: 22050383 DOI: 10.1111/j.1439-0531.2011.01936.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Studies to date have shown that bison embryo development in vitro is compromised with few embryos developing to the blastocyst stage. The aim of this study was to use bison-cattle hybrid embryos, an interspecific cross that is known to result in live offspring in vivo, as a model for assessing species-specific differences in embryo development in vitro. Cattle oocytes fertilized with cattle, plains bison and wood bison sperm were assessed for various developmental parameters associated with embryo quality, including cell number, apoptosis and ATP content. Decreased development to the blastocyst stage was observed in hybrid wood bison embryos compared with the other treatment groups. Although both wood bison and plains bison hybrid blastocysts had significantly lower cell numbers than cattle blastocysts, only wood bison hybrid blastocysts had a greater incidence of apoptosis than cattle blastocysts. Among the treatment groups, ATP levels and expression profiles of NRF1, TFAM, MT-CYB, BAX and BCL2 were not significantly different in both 8- to 16-cell stage and blastocyst stage embryos. These data provide evidence of decreased developmental competence in the wood bison hybrid embryos, owing to inadequate culture conditions that have increased apoptotic events.
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Affiliation(s)
- R P Seaby
- Department of Biomedical Sciences, University of Guelph, Guelph, Ontario N1G 2W1, Canada
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