Manufacturing a Female Gamete: An Oocyte Story

A special issue of Cells (ISSN 2073-4409). This special issue belongs to the section "Cell Proliferation and Division".

Deadline for manuscript submissions: closed (15 April 2020) | Viewed by 74539

Special Issue Editors


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Guest Editor
Developmental Biology Laboratory, Institute of Biology Paris-Seine, Sorbonne University, CNRS, Paris, France
Interests: oocyte meiotic divisions in Xenopus; signal transduction; kinases and phosphatases; biochemistry of cell division; oogenesis
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Co-Guest Editor
Villefranche-sur-mer Developmental Biology Laboratory , IMEV, Sorbonne University– CNRS, 06230 Villefranche-sur-mer, France
Interests: developmental biology; oogenesis; cnidarians

Special Issue Information

Dear Colleagues,

The continuity of life on earth has been ensured since its apparition more than 3.5 billions years ago: Cells only arise from pre-existing cells. In multicellular organisms, unlike the “perishable body of the individual”, something—the “hereditary substance”—has to be passed from generation to generation (in quotes: Wording of August Weissman, 1892). This is the duty of gametes: Oocytes and sperm. Building a fertilizable female gamete is then one of the founding elements of the sexual reproduction of multicellular organisms. This construction is a lengthy, complex, and highly coordinated saga that begins with an undetermined germ cell and transforms it into an oocyte capable of being fertilized. How germ cells come to be oocytes involves profound cell transformations: The construction of a polarized cell infrastructure, extraordinary cell growth, haploid and recombined genetic equipment, and competence with regard to fertilization, all of which are necessary to support the development of the future embryo. This manufacturing implies many specialized and decision-making processes: Communication and interactions between germ cells and somatic cells, meiotic chromosome pairing and homologous recombination, controlled expression of maternal information, metabolic requirements, complex signaling cascades, highly specialized cell divisions, and specific chromosome segregation, supported by adapted cytoskeleton organization and chromatin remodeling.

This Special Issue of Cells should present a comprehensive overview of the oogenesis process in chronological order, including chapters on diverse model organisms that offer an evolutionary perspective to sexual reproduction as well as others covering medical considerations. Based on the contributions of world-leading experts, this Special Issue will be an essential reference for students, researchers, and physicians in the exciting field of research on this fascinating cell.

Dr. Catherine Jessus
Guest Editor

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Keywords

  • Oocyte
  • Oogenesis
  • Meiosis
  • Meiotic spindle
  • Meiotic recombination
  • Fertilization

Published Papers (16 papers)

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Research

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14 pages, 2330 KiB  
Article
A Peak of H3T3 Phosphorylation Occurs in Synchrony with Mitosis in Sea Urchin Early Embryos
by Omid Feizbakhsh, Florian Pontheaux, Virginie Glippa, Julia Morales, Sandrine Ruchaud, Patrick Cormier and Fernando Roch
Cells 2020, 9(4), 898; https://doi.org/10.3390/cells9040898 - 07 Apr 2020
Cited by 4 | Viewed by 2816
Abstract
The sea urchin embryo provides a valuable system to analyse the molecular mechanisms orchestrating cell cycle progression and mitosis in a developmental context. However, although it is known that the regulation of histone activity by post-translational modification plays an important role during cell [...] Read more.
The sea urchin embryo provides a valuable system to analyse the molecular mechanisms orchestrating cell cycle progression and mitosis in a developmental context. However, although it is known that the regulation of histone activity by post-translational modification plays an important role during cell division, the dynamics and the impact of these modifications have not been characterised in detail in a developing embryo. Using different immuno-detection techniques, we show that the levels of Histone 3 phosphorylation at Threonine 3 oscillate in synchrony with mitosis in Sphaerechinus granularis early embryos. We present, in addition, the results of a pharmacological study aimed at analysing the role of this key histone post-translational modification during sea urchin early development. Full article
(This article belongs to the Special Issue Manufacturing a Female Gamete: An Oocyte Story)
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13 pages, 1436 KiB  
Article
CRISPR/Cas9-Mediated Genome Editing Reveals Oosp Family Genes are Dispensable for Female Fertility in Mice
by Ferheen Abbasi, Mayo Kodani, Chihiro Emori, Daiji Kiyozumi, Masashi Mori, Yoshitaka Fujihara and Masahito Ikawa
Cells 2020, 9(4), 821; https://doi.org/10.3390/cells9040821 - 28 Mar 2020
Cited by 8 | Viewed by 4812
Abstract
There are over 200 genes that are predicted to be solely expressed in the oocyte and ovary, and thousands more that have expression patterns in the female reproductive tract. Unfortunately, many of their physiological functions, such as their roles in oogenesis or fertilization, [...] Read more.
There are over 200 genes that are predicted to be solely expressed in the oocyte and ovary, and thousands more that have expression patterns in the female reproductive tract. Unfortunately, many of their physiological functions, such as their roles in oogenesis or fertilization, have yet to be elucidated. Previous knockout (KO) mice studies have proven that many of the genes that were once thought to be essential for fertility are dispensable in vivo. Therefore, it is extremely important to confirm the roles of all genes before spending immense time studying them in vitro. To do this, our laboratory analyzes the functions of ovary and oocyte-enriched genes in vivo through generating CRISPR/Cas9 KO mice and examining their fertility. In this study, we have knocked out three Oosp family genes (Oosp1, Oosp2, and Oosp3) that have expression patterns linked to the female reproductive system and found that the triple KO (TKO) mutant mice generated exhibited decreased prolificacy but were not infertile; thus, these genes may potentially be dispensable for fertility. We also generated Cd160 and Egfl6 KO mice and found these genes are individually dispensable for female fertility. KO mice with no phenotypic data are seldom published, but we believe that this information must be shared to prevent unnecessary experimentation by other laboratories. Full article
(This article belongs to the Special Issue Manufacturing a Female Gamete: An Oocyte Story)
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22 pages, 2983 KiB  
Article
Hydrogen Sulfide Impairs Meiosis Resumption in Xenopus laevis Oocytes
by Armance Gelaude, Sylvain Slaby, Katia Cailliau, Matthieu Marin, Arlette Lescuyer-Rousseau, Caroline Molinaro, Jan Nevoral, Veronica Kučerová-Chrpová, Marketa Sedmikova, Jaroslav Petr, Alain Martoriati and Jean-François Bodart
Cells 2020, 9(1), 237; https://doi.org/10.3390/cells9010237 - 17 Jan 2020
Cited by 3 | Viewed by 3377
Abstract
The role of hydrogen sulfide (H2S) is addressed in Xenopus laevis oocytes. Three enzymes involved in H2S metabolism, cystathionine β-synthase, cystathionine γ-lyase, and 3-mercaptopyruvate sulfurtransferase, were detected in prophase I and metaphase II-arrested oocytes and drove an acceleration of [...] Read more.
The role of hydrogen sulfide (H2S) is addressed in Xenopus laevis oocytes. Three enzymes involved in H2S metabolism, cystathionine β-synthase, cystathionine γ-lyase, and 3-mercaptopyruvate sulfurtransferase, were detected in prophase I and metaphase II-arrested oocytes and drove an acceleration of oocyte meiosis resumption when inhibited. Moreover, meiosis resumption is associated with a significant decrease in endogenous H2S. On another hand, a dose-dependent inhibition was obtained using the H2S donor, NaHS (1 and 5 mM). NaHS impaired translation. NaHS did not induce the dissociation of the components of the M-phase promoting factor (MPF), cyclin B and Cdk1, nor directly impacted the MPF activity. However, the M-phase entry induced by microinjection of metaphase II MPF-containing cytoplasm was diminished, suggesting upstream components of the MPF auto-amplification loop were sensitive to H2S. Superoxide dismutase and catalase hindered the effects of NaHS, and this sensitivity was partially dependent on the production of reactive oxygen species (ROS). In contrast to other species, no apoptosis was promoted. These results suggest a contribution of H2S signaling in the timing of amphibian oocytes meiosis resumption. Full article
(This article belongs to the Special Issue Manufacturing a Female Gamete: An Oocyte Story)
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24 pages, 8277 KiB  
Article
N-Cadherin Is Critical for the Survival of Germ Cells, the Formation of Steroidogenic Cells, and the Architecture of Developing Mouse Gonads
by Rafal P. Piprek, Michal Kolasa, Dagmara Podkowa, Malgorzata Kloc and Jacek Z. Kubiak
Cells 2019, 8(12), 1610; https://doi.org/10.3390/cells8121610 - 11 Dec 2019
Cited by 11 | Viewed by 3760
Abstract
Normal gonad development assures the fertility of the individual. The properly functioning gonads must contain a sufficient number of the viable germ cells, possess a correct architecture and tissue structure, and assure the proper hormonal regulation. This is achieved by the interplay between [...] Read more.
Normal gonad development assures the fertility of the individual. The properly functioning gonads must contain a sufficient number of the viable germ cells, possess a correct architecture and tissue structure, and assure the proper hormonal regulation. This is achieved by the interplay between the germ cells and different types of somatic cells. N-cadherin coded by the Cdh2 gene plays a critical role in this interplay. To gain an insight into the role of N-cadherin in the development of mouse gonads, we used the Cre-loxP system to knock out N-cadherin separately in two cell lines: the SF1+ somatic cells and the OCT4+ germ cells. We observed that N-cadherin plays a key role in the survival of both female and male germ cells. However, the N-cadherin is not necessary for the differentiation of the Sertoli cells or the initiation of the formation of testis cords or ovigerous cords. In the later stages of gonad development, N-cadherin is important for the maintenance of testis cord structure and is required for the formation of steroidogenic cells. In the ovaries, N-cadherin is necessary for the formation of the ovarian follicles. These results indicate that N-cadherin plays a major role in gonad differentiation, structuralization, and function. Full article
(This article belongs to the Special Issue Manufacturing a Female Gamete: An Oocyte Story)
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18 pages, 1027 KiB  
Article
Mathematical Model Explaining the Role of CDC6 in the Diauxic Growth of CDK1 Activity during the M-Phase of the Cell Cycle
by Mateusz Dębowski, Zuzanna Szymańska, Jacek Z. Kubiak and Mirosław Lachowicz
Cells 2019, 8(12), 1537; https://doi.org/10.3390/cells8121537 - 28 Nov 2019
Cited by 4 | Viewed by 2821
Abstract
In this paper we propose a role for the CDC 6 protein in the entry of cells into mitosis. This has not been considered in the literature so far. Recent experiments suggest that CDC 6 , upon entry into mitosis, inhibits the appearance [...] Read more.
In this paper we propose a role for the CDC 6 protein in the entry of cells into mitosis. This has not been considered in the literature so far. Recent experiments suggest that CDC 6 , upon entry into mitosis, inhibits the appearance of active CDK 1 and cyclin B complexes. This paper proposes a mathematical model which incorporates the dynamics of kinase CDK 1 , its regulatory protein cyclin B, the regulatory phosphatase CDC 25 and the inhibitor CDC 6 known to be involved in the regulation of active CDK 1 and cyclin B complexes. The experimental data lead us to formulate a new hypothesis that CDC 6 slows down the activation of inactive complexes of CDK 1 and cyclin B upon mitotic entry. Our mathematical model, based on mass action kinetics, provides a possible explanation for the experimental data. We claim that the dynamics of active complexes CDK 1 and cyclin B have a similar nature to diauxic dynamics introduced by Monod in 1949. In mathematical terms we state it as the existence of more than one inflection point of the curve defining the dynamics of the complexes. Full article
(This article belongs to the Special Issue Manufacturing a Female Gamete: An Oocyte Story)
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Review

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24 pages, 5381 KiB  
Review
Translational Control of Xenopus Oocyte Meiosis: Toward the Genomic Era
by Ferdinand Meneau, Aude Dupré, Catherine Jessus and Enrico Maria Daldello
Cells 2020, 9(6), 1502; https://doi.org/10.3390/cells9061502 - 19 Jun 2020
Cited by 18 | Viewed by 4925
Abstract
The study of oocytes has made enormous contributions to the understanding of the G2/M transition. The complementarity of investigations carried out on various model organisms has led to the identification of the M-phase promoting factor (MPF) and to unravel the basis [...] Read more.
The study of oocytes has made enormous contributions to the understanding of the G2/M transition. The complementarity of investigations carried out on various model organisms has led to the identification of the M-phase promoting factor (MPF) and to unravel the basis of cell cycle regulation. Thanks to the power of biochemical approaches offered by frog oocytes, this model has allowed to identify the core signaling components involved in the regulation of M-phase. A central emerging layer of regulation of cell division regards protein translation. Oocytes are a unique model to tackle this question as they accumulate large quantities of dormant mRNAs to be used during meiosis resumption and progression, as well as the cell divisions during early embryogenesis. Since these events occur in the absence of transcription, they require cascades of successive unmasking, translation, and discarding of these mRNAs, implying a fine regulation of the timing of specific translation. In the last years, the Xenopus genome has been sequenced and annotated, enabling the development of omics techniques in this model and starting its transition into the genomic era. This review has critically described how the different phases of meiosis are orchestrated by changes in gene expression. The physiological states of the oocyte have been described together with the molecular mechanisms that control the critical transitions during meiosis progression, highlighting the connection between translation control and meiosis dynamics. Full article
(This article belongs to the Special Issue Manufacturing a Female Gamete: An Oocyte Story)
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36 pages, 6819 KiB  
Review
Managing the Oocyte Meiotic Arrest—Lessons from Frogs and Jellyfish
by Catherine Jessus, Catriona Munro and Evelyn Houliston
Cells 2020, 9(5), 1150; https://doi.org/10.3390/cells9051150 - 07 May 2020
Cited by 16 | Viewed by 5718
Abstract
During oocyte development, meiosis arrests in prophase of the first division for a remarkably prolonged period firstly during oocyte growth, and then when awaiting the appropriate hormonal signals for egg release. This prophase arrest is finally unlocked when locally produced maturation initiation hormones [...] Read more.
During oocyte development, meiosis arrests in prophase of the first division for a remarkably prolonged period firstly during oocyte growth, and then when awaiting the appropriate hormonal signals for egg release. This prophase arrest is finally unlocked when locally produced maturation initiation hormones (MIHs) trigger entry into M-phase. Here, we assess the current knowledge of the successive cellular and molecular mechanisms responsible for keeping meiotic progression on hold. We focus on two model organisms, the amphibian Xenopus laevis, and the hydrozoan jellyfish Clytia hemisphaerica. Conserved mechanisms govern the initial meiotic programme of the oocyte prior to oocyte growth and also, much later, the onset of mitotic divisions, via activation of two key kinase systems: Cdk1-Cyclin B/Gwl (MPF) for M-phase activation and Mos-MAPkinase to orchestrate polar body formation and cytostatic (CSF) arrest. In contrast, maintenance of the prophase state of the fully-grown oocyte is assured by highly specific mechanisms, reflecting enormous variation between species in MIHs, MIH receptors and their immediate downstream signalling response. Convergence of multiple signalling pathway components to promote MPF activation in some oocytes, including Xenopus, is likely a heritage of the complex evolutionary history of spawning regulation, but also helps ensure a robust and reliable mechanism for gamete production. Full article
(This article belongs to the Special Issue Manufacturing a Female Gamete: An Oocyte Story)
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27 pages, 1784 KiB  
Review
A Comparative Analysis of Oocyte Development in Mammals
by Rozenn Dalbies-Tran, Véronique Cadoret, Alice Desmarchais, Sébastien Elis, Virginie Maillard, Philippe Monget, Danielle Monniaux, Karine Reynaud, Marie Saint-Dizier and Svetlana Uzbekova
Cells 2020, 9(4), 1002; https://doi.org/10.3390/cells9041002 - 17 Apr 2020
Cited by 42 | Viewed by 6238
Abstract
Sexual reproduction requires the fertilization of a female gamete after it has undergone optimal development. Various aspects of oocyte development and many molecular actors in this process are shared among mammals, but phylogeny and experimental data reveal species specificities. In this chapter, we [...] Read more.
Sexual reproduction requires the fertilization of a female gamete after it has undergone optimal development. Various aspects of oocyte development and many molecular actors in this process are shared among mammals, but phylogeny and experimental data reveal species specificities. In this chapter, we will present these common and distinctive features with a focus on three points: the shaping of the oocyte transcriptome from evolutionarily conserved and rapidly evolving genes, the control of folliculogenesis and ovulation rate by oocyte-secreted Growth and Differentiation Factor 9 and Bone Morphogenetic Protein 15, and the importance of lipid metabolism. Full article
(This article belongs to the Special Issue Manufacturing a Female Gamete: An Oocyte Story)
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19 pages, 1248 KiB  
Review
Mixing and Matching Chromosomes during Female Meiosis
by Thomas Rubin, Nicolas Macaisne and Jean-René Huynh
Cells 2020, 9(3), 696; https://doi.org/10.3390/cells9030696 - 12 Mar 2020
Cited by 21 | Viewed by 6129
Abstract
Meiosis is a key event in the manufacturing of an oocyte. During this process, the oocyte creates a set of unique chromosomes by recombining paternal and maternal copies of homologous chromosomes, and by eliminating one set of chromosomes to become haploid. While meiosis [...] Read more.
Meiosis is a key event in the manufacturing of an oocyte. During this process, the oocyte creates a set of unique chromosomes by recombining paternal and maternal copies of homologous chromosomes, and by eliminating one set of chromosomes to become haploid. While meiosis is conserved among sexually reproducing eukaryotes, there is a bewildering diversity of strategies among species, and sometimes within sexes of the same species, to achieve proper segregation of chromosomes. Here, we review the very first steps of meiosis in females, when the maternal and paternal copies of each homologous chromosomes have to move, find each other and pair. We explore the similarities and differences observed in C. elegans, Drosophila, zebrafish and mouse females. Full article
(This article belongs to the Special Issue Manufacturing a Female Gamete: An Oocyte Story)
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20 pages, 3276 KiB  
Review
Diversity of RNA-Binding Proteins Modulating Post-Transcriptional Regulation of Protein Expression in the Maturing Mammalian Oocyte
by Marie Christou-Kent, Magali Dhellemmes, Emeline Lambert, Pierre F. Ray and Christophe Arnoult
Cells 2020, 9(3), 662; https://doi.org/10.3390/cells9030662 - 09 Mar 2020
Cited by 43 | Viewed by 6562
Abstract
The oocyte faces a particular challenge in terms of gene regulation. When oocytes resume meiosis at the end of the growth phase and prior to ovulation, the condensed chromatin state prevents the transcription of genes as they are required. Transcription is effectively silenced [...] Read more.
The oocyte faces a particular challenge in terms of gene regulation. When oocytes resume meiosis at the end of the growth phase and prior to ovulation, the condensed chromatin state prevents the transcription of genes as they are required. Transcription is effectively silenced from the late germinal vesicle (GV) stage until embryonic genome activation (EGA) following fertilisation. Therefore, during its growth, the oocyte must produce the mRNA transcripts needed to fulfil its protein requirements during the active period of meiotic completion, fertilisation, and the maternal-to zygote-transition (MZT). After meiotic resumption, gene expression control can be said to be transferred from the nucleus to the cytoplasm, from transcriptional regulation to translational regulation. Maternal RNA-binding proteins (RBPs) are the mediators of translational regulation and their role in oocyte maturation and early embryo development is vital. Understanding these mechanisms will provide invaluable insight into the oocyte’s requirements for developmental competence, with important implications for the diagnosis and treatment of certain types of infertility. Here, we give an overview of post-transcriptional regulation in the oocyte, emphasising the current knowledge of mammalian RBP mechanisms, and develop the roles of these mechanisms in the timely activation and elimination of maternal transcripts. Full article
(This article belongs to the Special Issue Manufacturing a Female Gamete: An Oocyte Story)
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28 pages, 1110 KiB  
Review
In Vitro Generation of Oocyte Like Cells and Their In Vivo Efficacy: How Far We have been Succeeded
by Dinesh Bharti, Si-Jung Jang, Sang-Yun Lee, Sung-Lim Lee and Gyu-Jin Rho
Cells 2020, 9(3), 557; https://doi.org/10.3390/cells9030557 - 27 Feb 2020
Cited by 16 | Viewed by 4978
Abstract
In the last few decades, stem cell therapy has grown as a boon for many pathological complications including female reproductive disorders. In this review, a brief description of available strategies that are related to stem cell-based in vitro oocyte-like cell (OLC) development are [...] Read more.
In the last few decades, stem cell therapy has grown as a boon for many pathological complications including female reproductive disorders. In this review, a brief description of available strategies that are related to stem cell-based in vitro oocyte-like cell (OLC) development are given. We have tried to cover all the aspects and latest updates of the in vitro OLC developmental methodologies, marker profiling, available disease models, and in vivo efficacies, with a special focus on mesenchymal stem cells (MSCs), induced pluripotent stem cells (iPSCs), and embryonic stem cells (ESCs) usage. The differentiation abilities of both the ovarian and non-ovarian stem cell sources under various induction conditions have shown different effects on morphological alterations, proliferation- and size-associated developments, hormonal secretions under gonadotropic stimulations, and their neo-oogenesis or folliculogenesis abilities after in vivo transplantations. The attainment of characters like oocyte-like morphology, size expansion, and meiosis initiation have been found to be major obstacles during in vitro oogenesis. A number of reports have either lacked in vivo studies or have shown their functional incapability to produce viable and healthy offspring. Though researchers have gained many valuable insights regarding in vitro gametogenesis, still there are many things to do to make stem cell-derived OLCs fully functional. Full article
(This article belongs to the Special Issue Manufacturing a Female Gamete: An Oocyte Story)
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14 pages, 1670 KiB  
Review
Microtubule-Based Mechanisms of Pronuclear Positioning
by Johnathan L. Meaders and David R. Burgess
Cells 2020, 9(2), 505; https://doi.org/10.3390/cells9020505 - 23 Feb 2020
Cited by 15 | Viewed by 4794
Abstract
The zygote is defined as a diploid cell resulting from the fusion of two haploid gametes. Union of haploid male and female pronuclei in many animals occurs through rearrangements of the microtubule cytoskeleton into a radial array of microtubules known as the sperm [...] Read more.
The zygote is defined as a diploid cell resulting from the fusion of two haploid gametes. Union of haploid male and female pronuclei in many animals occurs through rearrangements of the microtubule cytoskeleton into a radial array of microtubules known as the sperm aster. The sperm aster nucleates from paternally-derived centrioles attached to the male pronucleus after fertilization. Nematode, echinoderm, and amphibian eggs have proven as invaluable models to investigate the biophysical principles for how the sperm aster unites male and female pronuclei with precise spatial and temporal regulation. In this review, we compare these model organisms, discussing the dynamics of sperm aster formation and the different force generating mechanism for sperm aster and pronuclear migration. Finally, we provide new mechanistic insights for how sperm aster growth may influence sperm aster positioning. Full article
(This article belongs to the Special Issue Manufacturing a Female Gamete: An Oocyte Story)
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7 pages, 795 KiB  
Review
Oocyte Maturation in Starfish
by Kazuyoshi Chiba
Cells 2020, 9(2), 476; https://doi.org/10.3390/cells9020476 - 19 Feb 2020
Cited by 6 | Viewed by 3611
Abstract
Oocyte maturation is a process that occurs in the ovaries, where an immature oocyte resumes meiosis to attain competence for normal fertilization after ovulation/spawning. In starfish, the hormone 1-methyladenine binds to an unidentified receptor on the plasma membrane of oocytes, inducing a conformational [...] Read more.
Oocyte maturation is a process that occurs in the ovaries, where an immature oocyte resumes meiosis to attain competence for normal fertilization after ovulation/spawning. In starfish, the hormone 1-methyladenine binds to an unidentified receptor on the plasma membrane of oocytes, inducing a conformational change in the heterotrimeric GTP-binding protein α-subunit (Gα), so that the α-subunit binds GTP in exchange of GDP on the plasma membrane. The GTP-binding protein βγ-subunit (Gβγ) is released from Gα, and the released Gβγ activates phosphatidylinositol-3 kinase (PI3K), followed by the target of rapamycin kinase complex2 (TORC2) and 3-phosphoinositide-dependent protein kinase 1 (PDK1)-dependent phosphorylation of serum- and glucocorticoid-regulated kinase (SGK) of ovarian oocytes. Thereafter, SGK activates Na+/H+ exchanger (NHE) to increase the intracellular pH (pHi) from ~6.7 to ~6.9. Moreover, SGK phosphorylates Cdc25 and Myt1, thereby inducing the de-phosphorylation and activation of cyclin B–Cdk1, causing germinal vesicle breakdown (GVBD). Both pHi increase and GVBD are required for spindle assembly at metaphase I, followed by MI arrest at pHi 6.9 until spawning. Due to MI arrest or SGK-dependent pHi control, spawned oocytes can be fertilized normally Full article
(This article belongs to the Special Issue Manufacturing a Female Gamete: An Oocyte Story)
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16 pages, 753 KiB  
Review
A PP2A-B56—Centered View on Metaphase-to-Anaphase Transition in Mouse Oocyte Meiosis I
by Leonor Keating, Sandra A. Touati and Katja Wassmann
Cells 2020, 9(2), 390; https://doi.org/10.3390/cells9020390 - 07 Feb 2020
Cited by 8 | Viewed by 5741
Abstract
Meiosis is required to reduce to haploid the diploid genome content of a cell, generating gametes—oocytes and sperm—with the correct number of chromosomes. To achieve this goal, two specialized cell divisions without intermediate S-phase are executed in a time-controlled manner. In mammalian female [...] Read more.
Meiosis is required to reduce to haploid the diploid genome content of a cell, generating gametes—oocytes and sperm—with the correct number of chromosomes. To achieve this goal, two specialized cell divisions without intermediate S-phase are executed in a time-controlled manner. In mammalian female meiosis, these divisions are error-prone. Human oocytes have an exceptionally high error rate that further increases with age, with significant consequences for human fertility. To understand why errors in chromosome segregation occur at such high rates in oocytes, it is essential to understand the molecular players at work controlling these divisions. In this review, we look at the interplay of kinase and phosphatase activities at the transition from metaphase-to-anaphase for correct segregation of chromosomes. We focus on the activity of PP2A-B56, a key phosphatase for anaphase onset in both mitosis and meiosis. We start by introducing multiple roles PP2A-B56 occupies for progression through mitosis, before laying out whether or not the same principles may apply to the first meiotic division in oocytes, and describing the known meiosis-specific roles of PP2A-B56 and discrepancies with mitotic cell cycle regulation. Full article
(This article belongs to the Special Issue Manufacturing a Female Gamete: An Oocyte Story)
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12 pages, 1678 KiB  
Review
Modulation of Cell–Cell Interactions in Drosophila Oocyte Development
by Matthew Antel and Mayu Inaba
Cells 2020, 9(2), 274; https://doi.org/10.3390/cells9020274 - 22 Jan 2020
Cited by 9 | Viewed by 5393
Abstract
The Drosophila ovary offers a suitable model system to study the mechanisms that orchestrate diverse cellular processes. Oogenesis starts from asymmetric stem cell division, proper differentiation and the production of fully patterned oocytes equipped with all the maternal information required for embryogenesis. Spatial [...] Read more.
The Drosophila ovary offers a suitable model system to study the mechanisms that orchestrate diverse cellular processes. Oogenesis starts from asymmetric stem cell division, proper differentiation and the production of fully patterned oocytes equipped with all the maternal information required for embryogenesis. Spatial and temporal regulation of cell-cell interaction is particularly important to fulfill accurate biological outcomes at each step of oocyte development. Progress has been made in understanding diverse cell physiological regulation of signaling. Here we review the roles of specialized cellular machinery in cell-cell communication in different stages of oogenesis. Full article
(This article belongs to the Special Issue Manufacturing a Female Gamete: An Oocyte Story)
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Other

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1 pages, 158 KiB  
Erratum
Erratum: Bharti D., et al. In Vitro Generation of Oocyte Like Cells and Their In Vivo Efficacy: How Far We have been Succeeded. Cells 2020, 9, 557
by Dinesh Bharti, Si-Jung Jang, Sang-Yun Lee, Sung-Lim Lee and Gyu-Jin Rho
Cells 2020, 9(5), 1262; https://doi.org/10.3390/cells9051262 - 20 May 2020
Cited by 3 | Viewed by 1535
Abstract
The wrong grant number was erroneously entered in the original manuscript and needs to be changed from NRF-2017R1D1A1B03035677 to NRF-2019R1I1A3A01060073 in [...] Full article
(This article belongs to the Special Issue Manufacturing a Female Gamete: An Oocyte Story)
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