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PAK2 is essential for chromosome alignment in metaphase I oocytes. Cell Death Dis 2023; 14:150. [PMID: 36813765 PMCID: PMC9947007 DOI: 10.1038/s41419-023-05585-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2022] [Revised: 01/11/2023] [Accepted: 01/12/2023] [Indexed: 02/24/2023]
Abstract
As a highly conserved and ubiquitously expressed serine/threonine kinase, p21-activated kinase 2 (PAK2) participates in diverse biologic events. However, its roles in mouse oocyte meiotic maturation remain unclear. The present study revealed that mouse oocytes depleted of Pak2 were unable to completely progress through meiosis and that a majority were arrested at metaphase I. Pak2 depletion thus prompted MI arrest and induced meiotic chromosome alignment defects in mouse oocytes, in part due to a reduction in polo-like kinase (PLK1). We demonstrated that PAK2's interaction with PLK1 protected it from degradation by APC/CCdh1, and that it promoted meiotic progression and bipolar spindle formation. Our data collectively display critical functions for PAK2 in meiotic progression and chromosome alignment in mouse oocytes.
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Rathbun LI, Aljiboury AA, Bai X, Hall NA, Manikas J, Amack JD, Bembenek JN, Hehnly H. PLK1- and PLK4-Mediated Asymmetric Mitotic Centrosome Size and Positioning in the Early Zebrafish Embryo. Curr Biol 2020; 30:4519-4527.e3. [PMID: 32916112 PMCID: PMC8159022 DOI: 10.1016/j.cub.2020.08.074] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Revised: 08/11/2020] [Accepted: 08/21/2020] [Indexed: 12/13/2022]
Abstract
Factors that regulate mitotic spindle positioning remain unclear within the confines of extremely large embryonic cells, such as the early divisions of the vertebrate embryo, Danio rerio (zebrafish). We find that the mitotic centrosome, a structure that assembles the mitotic spindle [1], is notably large in the zebrafish embryo (246.44 ± 11.93 μm2 in a 126.86 ± 0.35 μm diameter cell) compared to a C. elegans embryo (5.78 ± 0.18 μm2 in a 55.83 ± 1.04 μm diameter cell). During embryonic cell divisions, cell size changes rapidly in both C. elegans and zebrafish [2, 3], where mitotic centrosome area scales more closely with changes in cell size compared to changes in spindle length. Embryonic zebrafish spindles contain asymmetrically sized mitotic centrosomes (2.14 ± 0.13-fold difference between the two), with the larger mitotic centrosome placed toward the embryo center in a polo-like kinase (PLK) 1- and PLK4-dependent manner. We propose a model in which uniquely large zebrafish embryonic centrosomes direct spindle placement within disproportionately large cells.
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Affiliation(s)
- Lindsay I Rathbun
- Syracuse University, Department of Biology, 107 College Place, Syracuse, NY 13244, USA
| | - Abrar A Aljiboury
- Syracuse University, Department of Biology, 107 College Place, Syracuse, NY 13244, USA
| | - Xiaofei Bai
- University of Tennessee, Department of Biochemistry, Cellular and Molecular Biology, 1311 Cumberland Avenue, Knoxville, TN 37916, USA
| | - Nicole A Hall
- Syracuse University, Department of Biology, 107 College Place, Syracuse, NY 13244, USA
| | - Julie Manikas
- Syracuse University, Department of Biology, 107 College Place, Syracuse, NY 13244, USA
| | - Jeffrey D Amack
- SUNY Upstate Medical School, Department of Cell and Developmental Biology, 766 Irving Avenue, Syracuse, NY 13210, USA
| | - Joshua N Bembenek
- University of Tennessee, Department of Biochemistry, Cellular and Molecular Biology, 1311 Cumberland Avenue, Knoxville, TN 37916, USA; University of Michigan Medical School, Department of Molecular, Cellular, Developmental Biology, 1105 North University Avenue, Ann Arbor, MI 48109-1085, USA
| | - Heidi Hehnly
- Syracuse University, Department of Biology, 107 College Place, Syracuse, NY 13244, USA.
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Zheng W, Zhou Z, Sha Q, Niu X, Sun X, Shi J, Zhao L, Zhang S, Dai J, Cai S, Meng F, Hu L, Gong F, Li X, Fu J, Shi R, Lu G, Chen B, Fan H, Wang L, Lin G, Sang Q. Homozygous Mutations in BTG4 Cause Zygotic Cleavage Failure and Female Infertility. Am J Hum Genet 2020; 107:24-33. [PMID: 32502391 DOI: 10.1016/j.ajhg.2020.05.010] [Citation(s) in RCA: 53] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2020] [Accepted: 05/12/2020] [Indexed: 02/07/2023] Open
Abstract
Zygotic cleavage failure (ZCF) is a unique early embryonic phenotype resulting in female infertility and recurrent failure of in vitro fertilization (IVF) and/or intracytoplasmic sperm injection (ICSI). With this phenotype, morphologically normal oocytes can be retrieved and successfully fertilized, but they fail to undergo cleavage. Until now, whether this phenotype has a Mendelian inheritance pattern and which underlying genetic factors play a role in its development remained to be elucidated. B cell translocation gene 4 (BTG4) is a key adaptor of the CCR4-NOT deadenylase complex, which is involved in maternal mRNA decay in mice, but no human diseases caused by mutations in BTG4 have previously been reported. Here, we identified four homozygous mutations in BTG4 (GenBank: NM_017589.4) that are responsible for the phenotype of ZCF, and we found they followed a recessive inheritance pattern. Three of them-c.73C>T (p.Gln25Ter), c.1A>G (p.?), and c.475_478del (p.Ile159LeufsTer15)-resulted in complete loss of full-length BTG4 protein. For c.166G>A (p.Ala56Thr), although the protein level and distribution of mutant BTG4 was not altered in zygotes from affected individuals or in HeLa cells, the interaction between BTG4 and CNOT7 was abolished. In vivo studies further demonstrated that the process of maternal mRNA decay was disrupted in the zygotes of the affected individuals, which provides a mechanistic explanation for the phenotype of ZCF. Thus, we provide evidence that ZCF is a Mendelian phenotype resulting from mutations in BTG4. These findings contribute to our understanding of the role of BTG4 in human early embryonic development and provide a genetic marker for female infertility.
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Affiliation(s)
- Wei Zheng
- Clinical Research Center for Reproduction and Genetics in Hunan Province, Reproductive and Genetic Hospital of CITIC-Xiangya, Changsha, 410078, China
| | - Zhou Zhou
- Institute of Pediatrics, Children's Hospital of Fudan University and the Shanghai Key Laboratory of Medical Epigenetics, International Co-laboratory of Medical Epigenetics and Metabolism, Ministry of Science and Technology and Institutes of Biomedical Sciences, State Key Laboratory of Genetic Engineering, Fudan University, Shanghai, 200032, China
| | - Qianqian Sha
- Fertility Preservation Laboratory, Reproductive Medicine Center, Guangdong Second Provincial General Hospital, Guangzhou, 510317, China
| | - Xiangli Niu
- Reproductive Hospital of Guangxi Zhuang Autonomous Region, Nanning, 530021, China
| | - Xiaoxi Sun
- Shanghai Ji Ai Genetics and IVF Institute, Obstetrics and Gynecology Hospital, Fudan University, Shanghai, 200011, China
| | - Juanzi Shi
- Reproductive Medicine Center, Shaanxi Maternal and Child Care Service Center, Shaanxi, 710069, China
| | - Lei Zhao
- Clinical Research Center for Reproduction and Genetics in Hunan Province, Reproductive and Genetic Hospital of CITIC-Xiangya, Changsha, 410078, China
| | - Shuoping Zhang
- Clinical Research Center for Reproduction and Genetics in Hunan Province, Reproductive and Genetic Hospital of CITIC-Xiangya, Changsha, 410078, China
| | - Jing Dai
- Clinical Research Center for Reproduction and Genetics in Hunan Province, Reproductive and Genetic Hospital of CITIC-Xiangya, Changsha, 410078, China
| | - Sufen Cai
- Clinical Research Center for Reproduction and Genetics in Hunan Province, Reproductive and Genetic Hospital of CITIC-Xiangya, Changsha, 410078, China
| | - Fei Meng
- Clinical Research Center for Reproduction and Genetics in Hunan Province, Reproductive and Genetic Hospital of CITIC-Xiangya, Changsha, 410078, China
| | - Liang Hu
- Clinical Research Center for Reproduction and Genetics in Hunan Province, Reproductive and Genetic Hospital of CITIC-Xiangya, Changsha, 410078, China; Institute of Reproductive and Stem Cell Engineering, School of Basic Medical Science, Central South University, Changsha, 410078, China; Laboratory of Reproductive and Stem Cell Engineering, National Health and Family Planning Commission, Changsha, 410078, China
| | - Fei Gong
- Clinical Research Center for Reproduction and Genetics in Hunan Province, Reproductive and Genetic Hospital of CITIC-Xiangya, Changsha, 410078, China; Institute of Reproductive and Stem Cell Engineering, School of Basic Medical Science, Central South University, Changsha, 410078, China; Laboratory of Reproductive and Stem Cell Engineering, National Health and Family Planning Commission, Changsha, 410078, China
| | - Xiaoran Li
- Reproductive Hospital of Guangxi Zhuang Autonomous Region, Nanning, 530021, China
| | - Jing Fu
- Shanghai Ji Ai Genetics and IVF Institute, Obstetrics and Gynecology Hospital, Fudan University, Shanghai, 200011, China
| | - Rong Shi
- Reproductive Medicine Center, Shaanxi Maternal and Child Care Service Center, Shaanxi, 710069, China
| | - Guangxiu Lu
- Clinical Research Center for Reproduction and Genetics in Hunan Province, Reproductive and Genetic Hospital of CITIC-Xiangya, Changsha, 410078, China; Institute of Reproductive and Stem Cell Engineering, School of Basic Medical Science, Central South University, Changsha, 410078, China; Laboratory of Reproductive and Stem Cell Engineering, National Health and Family Planning Commission, Changsha, 410078, China
| | - Biaobang Chen
- NHC Key Lab of Reproduction Regulation (Shanghai Institute of Planned Parenthood Research), Shanghai, 200032, China
| | - Hengyu Fan
- Life Sciences Institute, Zhejiang University, Hangzhou, 310058, China
| | - Lei Wang
- Institute of Pediatrics, Children's Hospital of Fudan University and the Shanghai Key Laboratory of Medical Epigenetics, International Co-laboratory of Medical Epigenetics and Metabolism, Ministry of Science and Technology and Institutes of Biomedical Sciences, State Key Laboratory of Genetic Engineering, Fudan University, Shanghai, 200032, China; Shanghai Center for Women and Children's Health, Shanghai, 200062, China
| | - Ge Lin
- Clinical Research Center for Reproduction and Genetics in Hunan Province, Reproductive and Genetic Hospital of CITIC-Xiangya, Changsha, 410078, China; Institute of Reproductive and Stem Cell Engineering, School of Basic Medical Science, Central South University, Changsha, 410078, China; Laboratory of Reproductive and Stem Cell Engineering, National Health and Family Planning Commission, Changsha, 410078, China.
| | - Qing Sang
- Institute of Pediatrics, Children's Hospital of Fudan University and the Shanghai Key Laboratory of Medical Epigenetics, International Co-laboratory of Medical Epigenetics and Metabolism, Ministry of Science and Technology and Institutes of Biomedical Sciences, State Key Laboratory of Genetic Engineering, Fudan University, Shanghai, 200032, China.
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Moon J, Roh S. Expression of polo-like kinase 1 in pre-implantation stage murine somatic cell nuclear transfer embryos. J Vet Sci 2019; 20:2-9. [PMID: 30481982 PMCID: PMC6351765 DOI: 10.4142/jvs.2019.20.1.2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2018] [Revised: 10/23/2018] [Accepted: 11/06/2018] [Indexed: 11/23/2022] Open
Abstract
Somatic cell nuclear transfer (SCNT) has various applications in research, as well as in the medical field and animal husbandry. However, the efficiency of SCNT is low and the accurate mechanism of SCNT in murine embryo development is unreported. In general, the developmental rate of SCNT murine embryos is lower than in vivo counterparts. In previous studies, polo-like kinase 1 (Plk1) was reported to be a crucial element in cell division including centrosome maturation, cytokinesis, and spindle formation. In an initial series of experiments in this study, BI2536, a Plk1 inhibitor, was treated to in vivo-fertilized embryos and the embryos failed to develop beyond the 2-cell stage. This confirmed previous findings that Plk1 is crucial for the first mitotic division of murine embryos. Next, we investigated Plk1's localization and intensity by immunofluorescence analysis. In contrast to normally developed embryos, SCNT murine embryos that failed to develop exhibited two types of Plk1 expressions; a low Plk1 expression pattern and ectopic expression of Plk1. The results show that Plk1 has a critical role in SCNT murine embryos. In conclusion, this study demonstrated that the SCNT murine embryos fail to develop beyond the 2-cell stage, and the embryos show abnormal Plk1 expression patterns, which may one of the main causes of developmental failure of early SCNT murine embryos.
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Affiliation(s)
- Jeonghyeon Moon
- Cellular Reprogramming and Embryo Biotechnology Laboratory, Dental Research Institute, BK21 PLUS Dental Life Science, Seoul National University School of Dentistry, Seoul 08826, Korea
| | - Sangho Roh
- Cellular Reprogramming and Embryo Biotechnology Laboratory, Dental Research Institute, BK21 PLUS Dental Life Science, Seoul National University School of Dentistry, Seoul 08826, Korea
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Inhibition of Polo-like Kinase 1 Prevents the Male Pronuclear Formation Via Alpha-tubulin Recruiting in In Vivo-fertilized Murine Embryos. JOURNAL OF ANIMAL REPRODUCTION AND BIOTECHNOLOGY 2018. [DOI: 10.12750/jet.2018.33.4.229] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
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A novel mutation in the TUBB8 gene is associated with complete cleavage failure in fertilized eggs. J Assist Reprod Genet 2018; 35:1349-1356. [PMID: 29704226 DOI: 10.1007/s10815-018-1188-3] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2018] [Accepted: 04/13/2018] [Indexed: 01/08/2023] Open
Abstract
PURPOSE Cleavage of the zygote during human reproduction is a key event of early embryonic development. The genetic events associated with idiopathic embryonic cleavage failure are not certain. Mutations in the tubulin beta 8 class VIII (TUBB8) gene have been reported to be associated with oocyte maturation, fertilization, and developmental arrest. Here, we aimed to assess the clinical and genetic characteristics of complete cleavage failure in fertilized eggs. METHODS We have characterized a patient with a 9-year history of primary infertility in a non-consanguineous family from China. The patient presented complete cleavage failure in all two-pronuclear (2PN) fertilized oocytes after 2 cycles of in vitro fertilization (IVF). We performed Sanger sequencing of the TUBB8 gene in the patient, and further bioinformatics analysis to identify pathogenesis of gene. RESULTS A novel homozygous mutation, c.322G > A (p.Glu108Lys), was detected, and this change was absent from 179 control subjects. Glutamic acid is highly conserved at this position, and replacement by lysine was predicted to be repelled by the α-tubulin positive region, disrupting the α-β tubulin interaction. CONCLUSIONS Our findings presented a homozygous mutation of TUBB8 associated with complete cleavage failure in fertilized eggs and provided new data for the genotype-phenotype of TUBB8-related diseases.
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Liao Y, Lin D, Cui P, Abbasi B, Chen C, Zhang Z, Zhang Y, Dong Y, Rui R, Ju S. Polo-like kinase 1 inhibition results in misaligned chromosomes and aberrant spindles in porcine oocytes during the first meiotic division. Reprod Domest Anim 2018; 53:256-265. [PMID: 29143380 DOI: 10.1111/rda.13102] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2017] [Accepted: 09/26/2017] [Indexed: 01/15/2023]
Abstract
Polo-like kinase 1 (Plk1), a type of serine/threonine protein kinase, has been implicated in various functions in the regulation of mitotic processes. However, these kinase's roles in meiotic division are not fully understood, particularly in the meiotic maturation of porcine oocytes. In this study, the expression and spatiotemporal localization of Plk1 were initially assessed in the meiotic process of pig oocytes by utilizing Western blotting with immunofluorescent staining combined with confocal microscopy imaging technique. The results showed that Plk1 was expressed and exhibited a dynamic subcellular localization throughout the meiotic process. After germinal vesicle breakdown (GVBD), Plk1 was detected prominently around the condensed chromosomes and subsequently exhibited a similar subcellular localization to α-tubulin throughout subsequent meiotic phases, with particular enrichment being observed near spindle poles at MI and MII. Inhibition of Plk1 via a highly selective inhibitor, GSK461364, led to the failure of first polar body extrusion in porcine oocytes, with the majority of the treated oocytes being arrested in GVBD. Further subcellular structure examination results indicated that Plk1 inhibition caused the great majority of oocytes with spindle abnormalities and chromosome misalignment during the first meiotic division. The results of this study illustrate that Plk1 is critical for the first meiotic division in porcine oocytes through its influence on spindle organization and chromosome alignment, which further affects the ensuing meiotic cell cycle progression.
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Affiliation(s)
- Y Liao
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China
| | - D Lin
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China
| | - P Cui
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China
| | - B Abbasi
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China
| | - C Chen
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China
| | - Z Zhang
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China
| | - Y Zhang
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China
| | - Y Dong
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China
| | - R Rui
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China
| | - S Ju
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China
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Tšuiko O, Jatsenko T, Parameswaran Grace LK, Kurg A, Vermeesch JR, Lanner F, Altmäe S, Salumets A. A speculative outlook on embryonic aneuploidy: Can molecular pathways be involved? Dev Biol 2018; 447:3-13. [PMID: 29391166 DOI: 10.1016/j.ydbio.2018.01.014] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2017] [Revised: 12/27/2017] [Accepted: 01/22/2018] [Indexed: 01/21/2023]
Abstract
The journey of embryonic development starts at oocyte fertilization, which triggers a complex cascade of events and cellular pathways that guide early embryogenesis. Recent technological advances have greatly expanded our knowledge of cleavage-stage embryo development, which is characterized by an increased rate of whole-chromosome losses and gains, mixoploidy, and atypical cleavage morphokinetics. Embryonic aneuploidy significantly contributes to implantation failure, spontaneous miscarriage, stillbirth or congenital birth defects in both natural and assisted human reproduction. Essentially, early embryo development is strongly determined by maternal factors. Owing to considerable limitations associated with human oocyte and embryo research, the use of animal models is inevitable. However, cellular and molecular mechanisms driving the error-prone early stages of development are still poorly described. In this review, we describe known events that lead to aneuploidy in mammalian oocytes and preimplantation embryos. As the processes of oocyte and embryo development are rigorously regulated by multiple signal-transduction pathways, we explore the putative role of signaling pathways in genomic integrity maintenance. Based on the existing evidence from human and animal data, we investigate whether critical early developmental pathways, like Wnt, Hippo and MAPK, together with distinct DNA damage response and DNA repair pathways can be associated with embryo genomic instability, a question that has, so far, remained largely unexplored.
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Affiliation(s)
- Olga Tšuiko
- Department of Biomedicine, Institute of Bio- and Translational Medicine, University of Tartu, Tartu 50411, Estonia; Competence Centre on Health Technologies, Tartu 50410, Estonia
| | | | - Lalit Kumar Parameswaran Grace
- Department of Women's and Children's Health, Division of Obstetrics and Gynecology, Karolinska Institutet, Karolinska University Hospital, Stockholm 17176, Sweden
| | - Ants Kurg
- Department of Biotechnology, Institute of Molecular and Cell Biology, University of Tartu, Tartu 51010, Estonia
| | - Joris Robert Vermeesch
- Laboratory of Cytogenetics and Genome Research, Center of Human Genetics, KU Leuven, Leuven 3000, Belgium
| | - Fredrik Lanner
- Department of Clinical Science, Intervention, and Technology, Karolinska Institutet, Stockholm 14186, Sweden
| | - Signe Altmäe
- Competence Centre on Health Technologies, Tartu 50410, Estonia; Department of Biochemistry and Molecular Biology, Faculty of Sciences, University of Granada, Granada 18071, Spain.
| | - Andres Salumets
- Department of Biomedicine, Institute of Bio- and Translational Medicine, University of Tartu, Tartu 50411, Estonia; Competence Centre on Health Technologies, Tartu 50410, Estonia; Department of Obstetrics and Gynecology, Institute of Clinical Medicine, University of Tartu, Tartu 51014, Estonia; Department of Obstetrics and Gynecology, University of Helsinki and Helsinki University Hospital, Helsinki 00029, Finland
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Zhang Z, Chen C, Ma L, Yu Q, Li S, Abbasi B, Yang J, Rui R, Ju S. Plk1 is essential for proper chromosome segregation during meiosis I/meiosis II transition in pig oocytes. Reprod Biol Endocrinol 2017; 15:69. [PMID: 28851440 PMCID: PMC5575893 DOI: 10.1186/s12958-017-0289-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/07/2017] [Accepted: 08/13/2017] [Indexed: 02/23/2023] Open
Abstract
BACKGROUND Polo-like kinase 1 (Plk1), as a characteristic regulator in meiosis, organizes multiple biological events of cell division. Although Plk1 has been implicated in various functions in somatic cell mitotic processes, considerably less is known regarding its function during the transition from metaphase I (MI) to metaphase II (MII) stage in oocyte meiotic progression. METHODS In this study, the possible role of Plk1 during the MI-to-MII stage transition in pig oocytes was addressed. Initially, the spatiotemporal expression and subcellular localization pattern of Plk1 were revealed in pig oocytes from MI to MII stage using indirect immunofluorescence and confocal microscopy imaging techniques combined with western blot analyses. Moreover, a highly selective Plk1 inhibitor, GSK461364, was used to determine the potential role of Plk1 during this MI-to-MII transition progression. RESULTS Upon expression, Plk1 exhibited a specific dynamic intracellular localization, and co-localization of Plk1 with α-tubulin was revealed in the meiotic spindle of pig oocyte during the transition from MI to MII stage. GSK461364 treatment significantly blocked the first polar body (pbI) emission in a dose-dependent manner and resulted in a failure of meiotic maturation, with a larger percentage of the GSK461364-treated oocytes arresting in the anaphase-telophase I (ATI) stage. Further subcellular structure examination results showed that inhibition of Plk1 with GSK461364 had no visible effect on spindle assembly but caused a significantly higher proportion of the treated oocytes to have obvious defects in homologous chromosome segregation at ATI stage. CONCLUSIONS Thus, these results indicate that Plk1 plays an essential role during the meiosis I/meiosis II transition in porcine oocytes, and the regulation is associated with Plk1's effects on homologous chromosome segregation in the ATI stage.
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Affiliation(s)
- Zixiao Zhang
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, 210095 China
| | - Changchao Chen
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, 210095 China
| | - Liying Ma
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, 210095 China
| | - Qiuchen Yu
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, 210095 China
| | - Shuai Li
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, 210095 China
| | - Benazir Abbasi
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, 210095 China
| | - Jiayi Yang
- Nanjing Foreign Languages School, Nanjing, 210008 China
| | - Rong Rui
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, 210095 China
| | - Shiqiang Ju
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, 210095 China
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