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Valencia C, Pérez-García F, Aguila L, Felmer R, Arias ME. Combined Exogenous Activation of Bovine Oocytes: Effects on Maturation-Promoting Factor, Mitogen-Activated Protein Kinases, and Embryonic Competence. Int J Mol Sci 2023; 24:15794. [PMID: 37958778 PMCID: PMC10649646 DOI: 10.3390/ijms242115794] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2023] [Revised: 10/20/2023] [Accepted: 10/23/2023] [Indexed: 11/15/2023] Open
Abstract
Oocyte activation via dual inhibition of protein synthesis and phosphorylation has improved in vitro embryo production in different mammalian species. In this study, we evaluated the effects of the combination of cycloheximide (CHX), dimethyl amino purine (DMAP), and anisomycin (ANY) on the activation of bovine oocytes, particularly on dynamics of MPF and MAPKs, embryonic developmental potential, and quality. The results showed that the cleavage and blastocyst rates, as well as levels of CCNB1, CDK1, p-CDK1Thr161, and p-CDK1Thr14-Tyr15, were similar among groups; ANY and ANY + CHX reduced the expression of ERK1/2 compared to DMAP-combinations (p < 0.05), whereas ANY + DMAP, CHX + DMAP, and ANY + CHX + DMAP reduced p-ERK1/2 compared to ANY and ANY + CHX treatments (p < 0.05). The quality of blastocysts in terms of cell counts, their allocation, and the numbers of TUNEL-positive cells did not differ among groups. However, transcript levels of POU5F1 were higher in embryos derived from ANY + CHX + DMAP treatment compared to other groups, while expression levels of CDX2 did not show differences. In addition, the BCL2A1/BAX ratio of the ANY + CHX + DMAP treatment was significantly low compared to the ANY treatment (p < 0.05) and did not differ significantly from the other treatments. In conclusion, oocyte activation by dual inhibition of protein synthesis and phosphorylation induces MPF inactivation without degradation of CCNB1, while MAPK inactivation occurs differentially between these inhibitors. Thus, although the combined use of these inhibitors does not affect early developmental competence in vitro, it positively impacts the expression of transcripts associated with embryonic quality.
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Affiliation(s)
- Cecilia Valencia
- Laboratory of Reproduction, Centre of Reproductive Biotechnology (CEBIOR-BIOREN), Faculty of Medicine, Universidad de La Frontera, Temuco 4811322, Chile (L.A.); (R.F.)
| | - Felipe Pérez-García
- Laboratory of Reproduction, Centre of Reproductive Biotechnology (CEBIOR-BIOREN), Faculty of Medicine, Universidad de La Frontera, Temuco 4811322, Chile (L.A.); (R.F.)
| | - Luis Aguila
- Laboratory of Reproduction, Centre of Reproductive Biotechnology (CEBIOR-BIOREN), Faculty of Medicine, Universidad de La Frontera, Temuco 4811322, Chile (L.A.); (R.F.)
| | - Ricardo Felmer
- Laboratory of Reproduction, Centre of Reproductive Biotechnology (CEBIOR-BIOREN), Faculty of Medicine, Universidad de La Frontera, Temuco 4811322, Chile (L.A.); (R.F.)
- Department of Agricultural Sciences and Natural Resources, Faculty of Agriculture and Forestry Sciences, Universidad de La Frontera, Temuco 4811322, Chile
| | - María Elena Arias
- Laboratory of Reproduction, Centre of Reproductive Biotechnology (CEBIOR-BIOREN), Faculty of Medicine, Universidad de La Frontera, Temuco 4811322, Chile (L.A.); (R.F.)
- Department of Animal Production, Faculty of Agriculture and Forestry Sciences, Universidad de La Frontera, Temuco 4811322, Chile
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2
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Dehghan Z, Mohammadi-Yeganeh S, Salehi M. MiRNA-155 regulates cumulus cells function, oocyte maturation, and blastocyst formation. Biol Reprod 2020; 103:548-559. [DOI: 10.1093/biolre/ioaa098] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2020] [Revised: 04/05/2020] [Accepted: 06/02/2020] [Indexed: 12/24/2022] Open
Abstract
Abstract
Numerous oocytes are retrieved during in vitro fertilization from patients with polycystic ovary syndrome (PCOS). The poor quality of these oocytes leads to lower fertilization and decreases in cleavage and implantation. MiR-155 is one of the microRNA (miRNA) that is increased in serum and granulosa cells of PCOS patients. In this study, we investigate the effects of miR-155 expression and its target genes on oocyte maturation and embryo development. We used the calcium phosphate protocol to transfect vectors that contained miR-155 or miR-off 155 and alone eGFP into cumulus oophorus complex (COCs) of B6D2F1 female mice for in vitro maturation. Cumulus expansion, nuclear, and cytoplasmic maturation, as well as cleavage rates were determined in groups transfected and compared with the control groups. Quantitative real-time polymerase chain reaction was performed to analyze expression levels of miR-155 and the target genes in the cumulus cells, oocytes, and blastocysts. MiR-155 overexpression in COCs suppressed cumulus expansion, oocyte maturation, and inhibition of endogenous miR-155 by miR-off 155 improved cumulus expansion and oocyte maturation by downregulation and expression increase of the Smad2 and Bcl2 genes. On the other hand, overexpression and downregulation of miR-155 in the COCs led to increase and decrease in cleavage rates by changes in expressions of the Mecp2, Jarid2, and Notch1 genes, respectively (P < 0.05). These results suggested that miR-155 overexpression in granulosa cells of PCOS patients can negatively affect nuclear and cytoplasmic maturation, but this miRNA expression has a positive impact on embryo development.
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Affiliation(s)
- Zeinab Dehghan
- Department of Medical Biotechnology, School of Advanced Technologies in Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Samira Mohammadi-Yeganeh
- Cellular and Molecular Biology Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
- Department of Medical Biotechnology, School of Advanced Technologies in Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Mohammad Salehi
- Department of Medical Biotechnology, School of Advanced Technologies in Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
- Urogenital Stem Cell Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
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3
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Abstract
The early development of embryos is a widely studied process. Fertilization is the consequence of the fusion of two haploid gametes, the oocyte and the sperm. In mammals, such as human and mouse, this occurs in the female genital tracks. However, imaging in utero is still very limited, which prompts the use of extra utero techniques. In particular, in vitro fertilization provides a quick and simple way to study the very early steps of mouse embryo development. Here, I describe a simple and hands-on protocol to perform in vitro fertilization using the mouse as a model system.
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4
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Keshavarzi S, Salehi M, Farifteh-Nobijari F, Hosseini T, Hosseini S, Ghazifard A, Ghaffari Novin M, Fallah-Omrani V, Nourozian M, Hosseini A. Melatonin Modifies Histone Acetylation During In Vitro Maturation of Mouse Oocytes. CELL JOURNAL 2018; 20:244-249. [PMID: 29633602 PMCID: PMC5893296 DOI: 10.22074/cellj.2018.4860] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/10/2016] [Accepted: 04/09/2017] [Indexed: 11/09/2022]
Abstract
Objective We evaluated the effect of melatonin, as a potent antioxidant agent, on glutathione (GSH) and reactive
oxygen species (ROS) levels, as well as histone H3 lysine 9 (H3K9), and H4 lysine 12 (H4K12) acetylation when
added to oocytes culture medium.
Materials and Methods In this experimental study, two in vitro and in vivo groups were used. In the in vitro
group, cumulus oocyte complexes (COCs) from the ovaries of B6D2F1 mice were cultured in maturation medium
containing two doses of melatonin (10-9 and 10-6 M) and without melatonin [control group treated with dimethyl
sulfoxide (DMSO)] for 22-24 hour. The cumulus expansion and nuclear status were monitored by an inverted
microscope. Next, COCs were isolated from the oviducts of superovulated mice and studied as the in vivo group.
In in vitro and in vivo matured oocytes, GSH and ROS levels were assessed by monochlorobimane (MCB) and
2-7-dichlorodihydrofluorescein diacetate (H2DCFDA) staining, respectively. Changes in histone acetylation were
examined by immunofluorescent staining with specific antibodies against acetylated H3K9 and H4K12.
Results The H4K12 acetylation and ROS levels were significantly higher in the oocytes matured in the in
vitro group compared to the in vivo group (P<0.05). Furthermore, glutathione levels in the in vitro group were
considerably lower than that of the in vivo group (P<0.05). Melatonin at the concentration of 10-6 M had the most
substantial effect on nuclear maturation and histone acetylation as well as glutathione and ROS levels in the in
vitro group (P<0.05).
Conclusion Exogenous melatonin improves the competence of mouse oocytes during in vitro maturation (IVM).
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Affiliation(s)
- Somayeh Keshavarzi
- Cellular and Molecular Biology Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran.,Department of Biology and Anatomical Sciences, Faculty of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Mohammad Salehi
- Department of Biotechnology, Faculty of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran.,Department of Biotechnology, School of Advanced Technologies in Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Fattaneh Farifteh-Nobijari
- Cellular and Molecular Biology Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Taher Hosseini
- Cellular and Molecular Biology Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Sara Hosseini
- Cellular and Molecular Biology Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Alaleh Ghazifard
- Department of Biology and Anatomical Sciences, Faculty of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Marefat Ghaffari Novin
- Department of Biology and Anatomical Sciences, Faculty of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Vahid Fallah-Omrani
- Cellular and Molecular Biology Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Mohsen Nourozian
- Department of Biology and Anatomical Sciences, Faculty of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Ahmad Hosseini
- Cellular and Molecular Biology Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
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5
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Zhang QH, Yuen WS, Adhikari D, Flegg JA, FitzHarris G, Conti M, Sicinski P, Nabti I, Marangos P, Carroll J. Cyclin A2 modulates kinetochore-microtubule attachment in meiosis II. J Cell Biol 2017; 216:3133-3143. [PMID: 28819014 PMCID: PMC5626527 DOI: 10.1083/jcb.201607111] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2016] [Revised: 07/04/2017] [Accepted: 07/28/2017] [Indexed: 12/17/2022] Open
Abstract
Cyclin A2 is a crucial mitotic Cdk regulatory partner that coordinates entry into mitosis and is then destroyed in prometaphase within minutes of nuclear envelope breakdown. The role of cyclin A2 in female meiosis and its dynamics during the transition from meiosis I (MI) to meiosis II (MII) remain unclear. We found that cyclin A2 decreases in prometaphase I but recovers after the first meiotic division and persists, uniquely for metaphase, in MII-arrested oocytes. Conditional deletion of cyclin A2 from mouse oocytes has no discernible effect on MI but leads to disrupted MII spindles and increased merotelic attachments. On stimulation of exit from MII, there is a dramatic increase in lagging chromosomes and an inhibition of cytokinesis. These defects are associated with an increase in microtubule stability in MII spindles, suggesting that cyclin A2 mediates the fidelity of MII by maintaining microtubule dynamics during the rapid formation of the MII spindle.
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Affiliation(s)
- Qing-Hua Zhang
- Development and Stem Cell Program, Monash Biomedicine Discovery Institute, Monash University, Melbourne, Victoria, Australia .,Department of Anatomy and Developmental Biology, Monash University, Melbourne, Victoria, Australia
| | - Wai Shan Yuen
- Development and Stem Cell Program, Monash Biomedicine Discovery Institute, Monash University, Melbourne, Victoria, Australia.,Department of Anatomy and Developmental Biology, Monash University, Melbourne, Victoria, Australia
| | - Deepak Adhikari
- Development and Stem Cell Program, Monash Biomedicine Discovery Institute, Monash University, Melbourne, Victoria, Australia.,Department of Anatomy and Developmental Biology, Monash University, Melbourne, Victoria, Australia
| | - Jennifer A Flegg
- Monash Academy for Cross and Interdisciplinary Mathematical Applications, Monash University, Melbourne, Victoria, Australia
| | - Greg FitzHarris
- Centre de Recherche du Centre Hospitalier de l'Université de Montréal, Montréal, Québec, Canada.,Department of Obstetrics and Gynaecology, University of Montréal, Montréal, Québec, Canada
| | - Marco Conti
- Department of Obstetrics, Gynecology, and Reproductive Sciences, Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research, Center for Reproductive Sciences, University of California, San Francisco, San Francisco, CA
| | - Piotr Sicinski
- Dana-Farber Cancer Institute, Boston, MA.,Department of Genetics, Harvard Medical School, Boston, MA
| | - Ibtissem Nabti
- Department of Cell and Developmental Biology, University College London, London, England, UK.,Division of Science, New York University Abu Dhabi, Abu Dhabi, United Arab Emirates
| | - Petros Marangos
- Department of Cell and Developmental Biology, University College London, London, England, UK.,Department of Biological Applications and Technology, University of Ioannina, Ioannina, Greece.,Department of Biomedical Research, Institute of Molecular Biology and Biotechnology-Foundation for Research and Technology, Ioannina, Greece
| | - John Carroll
- Development and Stem Cell Program, Monash Biomedicine Discovery Institute, Monash University, Melbourne, Victoria, Australia .,Department of Anatomy and Developmental Biology, Monash University, Melbourne, Victoria, Australia.,Department of Cell and Developmental Biology, University College London, London, England, UK
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6
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Bevilacqua A, Bizzarri M. Physiological role and clinical utility of inositols in polycystic ovary syndrome. Best Pract Res Clin Obstet Gynaecol 2016; 37:129-139. [DOI: 10.1016/j.bpobgyn.2016.03.007] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2016] [Accepted: 03/09/2016] [Indexed: 11/16/2022]
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7
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Chaigne A, Campillo C, Voituriez R, Gov NS, Sykes C, Verlhac MH, Terret ME. F-actin mechanics control spindle centring in the mouse zygote. Nat Commun 2016; 7:10253. [PMID: 26727405 PMCID: PMC4725770 DOI: 10.1038/ncomms10253] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2015] [Accepted: 11/20/2015] [Indexed: 01/01/2023] Open
Abstract
Mitotic spindle position relies on interactions between astral microtubules nucleated by centrosomes and a rigid cortex. Some cells, such as mouse oocytes, do not possess centrosomes and astral microtubules. These cells rely only on actin and on a soft cortex to position their spindle off-centre and undergo asymmetric divisions. While the first mouse embryonic division also occurs in the absence of centrosomes, it is symmetric and not much is known on how the spindle is positioned at the exact cell centre. Using interdisciplinary approaches, we demonstrate that zygotic spindle positioning follows a three-step process: (1) coarse centring of pronuclei relying on the dynamics of an F-actin/Myosin-Vb meshwork; (2) fine centring of the metaphase plate depending on a high cortical tension; (3) passive maintenance at the cell centre. Altogether, we show that F-actin-dependent mechanics operate the switch between asymmetric to symmetric division required at the oocyte to embryo transition.
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Affiliation(s)
- Agathe Chaigne
- CIRB, Collège de France, and CNRS-UMR7241 and INSERM-U1050, Equipe labellisée Ligue contre le Cancer, Paris F-75005, France
| | - Clément Campillo
- Université Evry Val d'Essonne, LAMBE, Boulevard F Mitterrand, Evry 91025, France
| | | | - Nir S Gov
- Department of Chemical Physics, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Cécile Sykes
- CNRS-UMR168, Paris F-75248, France.,UPMC, 4 Place Jussieu, Paris F-75248, France.,Institut Curie, Centre de Recherche, Laboratoire Physico-Chimie, Paris F-75248, France
| | - Marie-Hélène Verlhac
- CIRB, Collège de France, and CNRS-UMR7241 and INSERM-U1050, Equipe labellisée Ligue contre le Cancer, Paris F-75005, France
| | - Marie-Emilie Terret
- CIRB, Collège de France, and CNRS-UMR7241 and INSERM-U1050, Equipe labellisée Ligue contre le Cancer, Paris F-75005, France
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8
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Bevilacqua A, Carlomagno G, Gerli S, Montanino Oliva M, Devroey P, Lanzone A, Soulange C, Facchinetti F, Carlo Di Renzo G, Bizzarri M, Hod M, Cavalli P, D'Anna R, Benvenga S, Chiu TT, Kamenov ZA. Results from the International Consensus Conference on myo-inositol and D-chiro-inositol in Obstetrics and Gynecology--assisted reproduction technology. Gynecol Endocrinol 2015; 31:441-6. [PMID: 26036719 DOI: 10.3109/09513590.2015.1006616] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
A substantial body of research on mammalian gametogenesis and human reproduction has recently investigated the effect of myo-inositol (MyoIns) on oocyte and sperm cell quality, due to its possible application to medically assisted reproduction. With a growing number of both clinical and basic research papers, the meaning of several observations now needs to be interpreted under a solid and rigorous physiological framework. The 2013 Florence International Consensus Conference on Myo- and D-chiro-inositol in obstetrics and gynecology has answered a number of research questions concerning the use of the two stereoisomers in assisted reproductive technologies. Available clinical trials and studies on the physiological and pharmacological effects of these molecules have been surveyed. Specifically, the physiological involvement of MyoIns in oocyte maturation and sperm cell functions has been discussed, providing an answer to the following questions: (1) Are inositols physiologically involved in oocyte maturation? (2) Are inositols involved in the physiology of spermatozoa function? (3) Is treatment with inositols helpful within assisted reproduction technology cycles? (4) Are there any differences in clinical efficacy between MyoIns and D-chiro-inositol? The conclusions of this Conference, drawn depending on expert panel opinions and shared with all the participants, are summarized in this review paper.
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Affiliation(s)
- Arturo Bevilacqua
- Department of Psychology, Sapienza University of Rome , Rome , Italy
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9
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Gonzalez-Garcia JR, Bradley J, Nomikos M, Paul L, Machaty Z, Lai FA, Swann K. The dynamics of MAPK inactivation at fertilization in mouse eggs. J Cell Sci 2014; 127:2749-60. [PMID: 24741069 PMCID: PMC4058113 DOI: 10.1242/jcs.145045] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Egg activation at fertilization in mammals is initiated by prolonged Ca(2+) oscillations that trigger the completion of meiosis and formation of pronuclei. A fall in mitogen-activated protein kinase (MAPK) activity is essential for pronuclear formation, but the precise timing and mechanism of decline are unknown. Here, we have measured the dynamics of MAPK pathway inactivation during fertilization of mouse eggs using novel chemiluminescent MAPK activity reporters. This reveals that the MAPK activity decrease begins during the Ca(2+) oscillations, but MAPK does not completely inactivate until after pronuclear formation. The MAPKs present in eggs are Mos, MAP2K1 and MAP2K2 (MEK1 and MEK2, respectively) and MAPK3 and MAPK1 (ERK1 and ERK2, respectively). Notably, the MAPK activity decline at fertilization is not explained by upstream destruction of Mos, because a decrease in the signal from a Mos-luciferase reporter is not associated with egg activation. Furthermore, Mos overexpression does not affect the timing of MAPK inactivation or pronuclear formation. However, the late decrease in MAPK could be rapidly reversed by the protein phosphatase inhibitor, okadaic acid. These data suggest that the completion of meiosis in mouse zygotes is driven by an increased phosphatase activity and not by a decline in Mos levels or MEK activity.
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Affiliation(s)
- Jose Raul Gonzalez-Garcia
- Institute of Molecular and Experimental Medicine, School of Medicine, Cardiff University, Cardiff CF14 4XN, UK
| | - Josephine Bradley
- Institute of Molecular and Experimental Medicine, School of Medicine, Cardiff University, Cardiff CF14 4XN, UK School of Biosciences, Cardiff University, Cardiff CF10 3AX, UK
| | - Michail Nomikos
- Institute of Molecular and Experimental Medicine, School of Medicine, Cardiff University, Cardiff CF14 4XN, UK
| | - Laboni Paul
- Institute of Molecular and Experimental Medicine, School of Medicine, Cardiff University, Cardiff CF14 4XN, UK School of Biosciences, Cardiff University, Cardiff CF10 3AX, UK
| | - Zoltan Machaty
- Department of Animal Sciences, Purdue University, West Lafayette, IN 47907, USA
| | - F Anthony Lai
- Institute of Molecular and Experimental Medicine, School of Medicine, Cardiff University, Cardiff CF14 4XN, UK
| | - Karl Swann
- Institute of Molecular and Experimental Medicine, School of Medicine, Cardiff University, Cardiff CF14 4XN, UK
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10
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Amdani SN, Jones C, Coward K. Phospholipase C zeta (PLCζ): oocyte activation and clinical links to male factor infertility. Adv Biol Regul 2013; 53:292-308. [PMID: 23916605 DOI: 10.1016/j.jbior.2013.07.005] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2013] [Accepted: 07/08/2013] [Indexed: 06/02/2023]
Abstract
Mounting scientific and clinical evidence supports the key role played by phospholipase C zeta (PLCζ), a sperm-specific protein, in the activation of oocytes following fertilisation. Lacking a pleckstrin homology domain, PLCζ remains the smallest known mammalian PLC and was first identified in 2002. Since then, PLCζ has been the target for a multitude of studies in both mammalian and non-mammalian species focused upon its fundamental biochemical activity and crucial role as the mediator of oocyte activation. The earliest event subsequent to gamete fusion is the onset of a series of intracellular calcium oscillations within the oocyte, which are known to modulate cortical granule exocytosis, release meiotic arrest, regulate gene expression, recruit maternal mRNA, and initiate embryogenesis. Collectively these processes are known as 'oocyte activation' and together, represent a fundamental mechanism for early embryonic development. Evidence suggests that these processes are initiated and controlled by calcium release from ooplasmic sources in response to PLCζ activity via the inositol-1,4,5-triphosphate (IP3) pathway. While the biochemical action of PLCζ has been extensively studied, especially in relation to the EF-hands, X-Y linker, and C2 domain, all of which play critical roles for in vivo activity, there are still key gaps in our knowledge, particularly in terms of regulation and interaction with other proteins within the oocyte. Moreover, increasing clinical evidence has revealed a strong correlation between certain types of male infertility and the aberrant expression, localisation, structure and function of PLCζ in human sperm, particularly in cases of recurrent intracytoplasmic sperm injection (ICSI) failure, globozoospermia, and oocyte activation deficiency (OAD). In addition, two heterozygous substitution mutations have been identified in the coding sequence of PLCζ in one particular patient causing disruption to the catalytic X and Y domains and resulting in infertility. Although, such cases can be treated via the use of artificial oocyte activators (AOAs) such as calcium ionophores, significant concern remains over the use of such chemical agents, largely due to the fact that calcium release manifests as a single transient, rather than a series of oscillations as observed during normal fertilisation. Current interest in PLCζ is thus to develop a series of prognostic, diagnostic and therapeutic approaches which could first identify male patients that are deficient in PLCζ and then rescue oocyte activation ability via assisted reproductive technology (ART) and a pure, functionally-active, recombinant human PLCζ protein. While significant progress has been made in such areas over recent years, there is a clear need to translate scientific findings to clinical settings in order to maximise successful outcome for patients.
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Affiliation(s)
- Siti Nornadhirah Amdani
- Nuffield Department of Obstetrics & Gynaecology, University of Oxford, Level 3, Women's Centre, John Radcliffe Hospital, Headington, Oxford, OX3 9DU, UK
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11
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Kim KH, Kim EY, Kim Y, Kim E, Lee HS, Yoon SY, Lee KA. Gas6 downregulation impaired cytoplasmic maturation and pronuclear formation independent to the MPF activity. PLoS One 2011; 6:e23304. [PMID: 21850267 PMCID: PMC3151302 DOI: 10.1371/journal.pone.0023304] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2011] [Accepted: 07/14/2011] [Indexed: 11/18/2022] Open
Abstract
Previously, we found that the growth arrest-specific gene 6 (Gas6) is more highly expressed in germinal vesicle (GV) oocytes than in metaphase II (MII) oocytes using annealing control primer (ACP)-PCR technology. The current study was undertaken to investigate the role of Gas6 in oocyte maturation and fertilization using RNA interference (RNAi). Interestingly, despite the specific and marked decrease in Gas6 mRNA and protein expression in GVs after Gas6 RNAi, nuclear maturation including spindle structures and chromosome segregation was not affected. The only discernible effect induced by Gas6 RNAi was a change in maturation promoting factor (MPF) activity. After parthenogenetic activation, Gas6 RNAi-treated oocytes at the MII stage had not developed further and arrested at MII (90.0%). After stimulation with Sr(2+), Gas6-silenced MII oocytes had markedly reduced Ca(2+) oscillation and exhibited no exocytosis of cortical granules. In these oocytes, sperm penetration occurred during fertilization but not pronucleus (PN) formation. By roscovitine and colcemid treatment, we found that the Gas6 knockdown affected cytoplasmic maturation directly, independent to the changed MPF activity. These results strongly suggest that 1) the Gas6 signaling itself is important to the cytoplasmic maturation, but not nuclear maturation, and 2) the decreased Gas6 expression and decreased MPF activity separately or mutually influence sperm head decondensation and PN formation.
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Affiliation(s)
- Kyeoung-Hwa Kim
- Department of Biomedical Science, College of Life Science, Fertility Center, CHA Research Institute, CHA University, CHA General Hospital, Seoul, Korea
| | - Eun-Young Kim
- Department of Biomedical Science, College of Life Science, Fertility Center, CHA Research Institute, CHA University, CHA General Hospital, Seoul, Korea
| | - Yuna Kim
- Department of Biomedical Science, College of Life Science, Fertility Center, CHA Research Institute, CHA University, CHA General Hospital, Seoul, Korea
| | - Eunju Kim
- Department of Biomedical Science, College of Life Science, Fertility Center, CHA Research Institute, CHA University, CHA General Hospital, Seoul, Korea
| | - Hyun-Seo Lee
- Department of Biomedical Science, College of Life Science, Fertility Center, CHA Research Institute, CHA University, CHA General Hospital, Seoul, Korea
| | - Sook-Young Yoon
- Department of Biomedical Science, College of Life Science, Fertility Center, CHA Research Institute, CHA University, CHA General Hospital, Seoul, Korea
| | - Kyung-Ah Lee
- Department of Biomedical Science, College of Life Science, Fertility Center, CHA Research Institute, CHA University, CHA General Hospital, Seoul, Korea
- * E-mail:
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12
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Kubiak JZ, El Dika M. Canonical and Alternative Pathways in Cyclin-Dependent Kinase 1/Cyclin B Inactivation upon M-Phase Exit in Xenopus laevis Cell-Free Extracts. Enzyme Res 2011; 2011:523420. [PMID: 21755042 PMCID: PMC3132491 DOI: 10.4061/2011/523420] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2011] [Revised: 04/01/2011] [Accepted: 04/18/2011] [Indexed: 11/20/2022] Open
Abstract
Cyclin-Dependent Kinase 1 (CDK1) is the major M-phase kinase known also as the M-phase Promoting Factor or MPF. Studies performed during the last decade have shown many details of how CDK1 is regulated and also how it regulates the cell cycle progression. Xenopus laevis cell-free extracts were widely used to elucidate the details and to obtain a global view of the role of CDK1 in M-phase control. CDK1 inactivation upon M-phase exit is a primordial process leading to the M-phase/interphase transition during the cell cycle. Here we discuss two closely related aspects of CDK1 regulation in Xenopus laevis cell-free extracts: firstly, how CDK1 becomes inactivated and secondly, how other actors, like kinases and phosphatases network and/or specific inhibitors, cooperate with CDK1 inactivation to assure timely exit from the M-phase.
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Affiliation(s)
- Jacek Z Kubiak
- Cell Cycle Group, Institute of Genetics & Development, University of Rennes 1, CNRS-UMR 6061, Faculty of Medicine, 2 Avenue Prof. Léon Bernard, CS 34317, 35043 Rennes Cedex, France
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Kashir J, Heindryckx B, Jones C, De Sutter P, Parrington J, Coward K. Oocyte activation, phospholipase C zeta and human infertility. Hum Reprod Update 2010; 16:690-703. [PMID: 20573804 DOI: 10.1093/humupd/dmq018] [Citation(s) in RCA: 171] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND Mammalian oocytes are activated by intracellular calcium (Ca(2+)) oscillations following gamete fusion. Recent evidence implicates a sperm-specific phospholipase C zeta, PLCζ, which is introduced into the oocyte following membrane fusion, as the responsible factor. This review summarizes the current understanding of human oocyte activation failure and describes recent discoveries linking certain cases of male infertility with defects in PLCζ expression and activity. How these latest findings may influence future diagnosis and treatment options are also discussed. METHODS Systematic literature searches were performed using PubMed, ISI-Web of Knowledge and The Cochrane Library. We also scrutinized material from the United Nations and World Health Organization databases (UNWHO) and the Human Fertilization and Embryology Authority (HFEA). RESULTS AND CONCLUSIONS Although ICSI results in average fertilization rates of 70%, complete or virtually complete fertilization failure still occurs in 1-5% of ICSI cycles. While oocyte activation failure can, in some cases, be overcome by artificial oocyte activators such as calcium ionophores, a more physiological oocyte activation agent might release Ca(2+) within the oocyte in a more efficient and controlled manner. As PLCζ is now widely considered to be the physiological agent responsible for activating mammalian oocytes, it represents both a novel diagnostic biomarker of oocyte activation capability and a possible mode of treatment for certain types of male infertility.
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Affiliation(s)
- J Kashir
- Nuffield Department of Obstetrics and Gynaecology, Level 3, Women's Centre, John Radcliffe Hospital, Headington, Oxford OX3 9DU, UK
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