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Zhang J, Ruiz M, Bergh PO, Henricsson M, Stojanović N, Devkota R, Henn M, Bohlooly-Y M, Hernández-Hernández A, Alsheimer M, Borén J, Pilon M, Shibuya H. Regulation of meiotic telomere dynamics through membrane fluidity promoted by AdipoR2-ELOVL2. Nat Commun 2024; 15:2315. [PMID: 38485951 PMCID: PMC10940294 DOI: 10.1038/s41467-024-46718-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2023] [Accepted: 02/29/2024] [Indexed: 03/18/2024] Open
Abstract
The cellular membrane in male meiotic germ cells contains a unique class of phospholipids and sphingolipids that is required for male reproduction. Here, we show that a conserved membrane fluidity sensor, AdipoR2, regulates the meiosis-specific lipidome in mouse testes by promoting the synthesis of sphingolipids containing very-long-chain polyunsaturated fatty acids (VLC-PUFAs). AdipoR2 upregulates the expression of a fatty acid elongase, ELOVL2, both transcriptionally and post-transcriptionally, to synthesize VLC-PUFA. The depletion of VLC-PUFAs and subsequent accumulation of palmitic acid in AdipoR2 knockout testes stiffens the cellular membrane and causes the invagination of the nuclear envelope. This condition impairs the nuclear peripheral distribution of meiotic telomeres, leading to errors in homologous synapsis and recombination. Further, the stiffened membrane impairs the formation of intercellular bridges and the germ cell syncytium, which disrupts the orderly arrangement of cell types within the seminiferous tubules. According to our findings we propose a framework in which the highly-fluid membrane microenvironment shaped by AdipoR2-ELOVL2 underpins meiosis-specific chromosome dynamics in testes.
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Affiliation(s)
- Jingjing Zhang
- Department of Chemistry and Molecular Biology, University of Gothenburg, 41390, Gothenburg, Sweden
| | - Mario Ruiz
- Department of Chemistry and Molecular Biology, University of Gothenburg, 41390, Gothenburg, Sweden
| | - Per-Olof Bergh
- Department of Molecular and Clinical Medicine/Wallenberg Laboratory, Institute of Medicine, University of Gothenburg, 41467, Gothenburg, Sweden
| | - Marcus Henricsson
- Department of Molecular and Clinical Medicine/Wallenberg Laboratory, Institute of Medicine, University of Gothenburg, 41467, Gothenburg, Sweden
| | - Nena Stojanović
- Department of Chemistry and Molecular Biology, University of Gothenburg, 41390, Gothenburg, Sweden
| | - Ranjan Devkota
- Department of Chemistry and Molecular Biology, University of Gothenburg, 41390, Gothenburg, Sweden
| | - Marius Henn
- Department of Cell and Developmental Biology, Biocenter, University of Würzburg, 97074, Würzburg, Germany
| | | | - Abrahan Hernández-Hernández
- Department of Cell and Molecular Biology, Karolinska Institutet, Stockholm, Sweden
- National Genomics Infrastructure, Science for Life Laboratory, Department of Cell and Molecular Biology, Karolinska Institute, Stockholm, Sweden
| | - Manfred Alsheimer
- Department of Cell and Developmental Biology, Biocenter, University of Würzburg, 97074, Würzburg, Germany
| | - Jan Borén
- Department of Molecular and Clinical Medicine/Wallenberg Laboratory, Institute of Medicine, University of Gothenburg, 41467, Gothenburg, Sweden
| | - Marc Pilon
- Department of Chemistry and Molecular Biology, University of Gothenburg, 41390, Gothenburg, Sweden.
| | - Hiroki Shibuya
- Department of Chemistry and Molecular Biology, University of Gothenburg, 41390, Gothenburg, Sweden.
- Laboratory for Gametogenesis, RIKEN Center for Biosystems Dynamics Research (BDR), Kobe, Japan.
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2
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Brubacher JL. Female Germline Cysts in Animals: Evolution and Function. Results Probl Cell Differ 2024; 71:23-46. [PMID: 37996671 DOI: 10.1007/978-3-031-37936-9_2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2023]
Abstract
Germline cysts are syncytia formed by incomplete cytokinesis of mitotic germline precursors (cystoblasts) in which the cystocytes are interconnected by cytoplasmic bridges, permitting the sharing of molecules and organelles. Among animals, such cysts are a nearly universal feature of spermatogenesis and are also often involved in oogenesis. Recent, elegant studies have demonstrated remarkable similarities in the oogenic cysts of mammals and insects, leading to proposals of widespread conservation of these features among animals. Unfortunately, such claims obscure the well-described diversity of female germline cysts in animals and ignore major taxa in which female germline cysts appear to be absent. In this review, I explore the phylogenetic patterns of oogenic cysts in the animal kingdom, with a focus on the hexapods as an informative example of a clade in which such cysts have been lost, regained, and modified in various ways. My aim is to build on the fascinating insights of recent comparative studies, by calling for a more nuanced view of evolutionary conservation. Female germline cysts in the Metazoa are an example of a phenomenon that-though essential for the continuance of many, diverse animal lineages-nevertheless exhibits intriguing patterns of evolutionary innovation, loss, and convergence.
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3
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Czukiewska SM, Fan X, Mulder AA, Van Der Helm T, Hillenius S, Van Der Meeren L, Matorras R, Eguizabal C, Lei L, Koning RI, Chuva De Sousa Lopes SM. Cell-cell interactions during the formation of primordial follicles in humans. Life Sci Alliance 2023; 6:e202301926. [PMID: 37643865 PMCID: PMC10465921 DOI: 10.26508/lsa.202301926] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2023] [Revised: 08/19/2023] [Accepted: 08/21/2023] [Indexed: 08/31/2023] Open
Abstract
Gametogenesis is a complex and sex-specific multistep process during which the gonadal somatic niche plays an essential regulatory role. One of the most crucial steps during human female gametogenesis is the formation of primordial follicles, the functional unit of the ovary that constitutes the pool of follicles available at birth during the entire reproductive life. However, the relation between human fetal germ cells (hFGCs) and gonadal somatic cells during the formation of the primordial follicles remains largely unexplored. We have discovered that hFGCs can form multinucleated syncytia, some connected via interconnecting intercellular bridges, and that not all nuclei in hFGC-syncytia were synchronous regarding meiotic stage. As hFGCs progressed in development, pre-granulosa cells formed protrusions that seemed to progressively constrict individual hFGCs, perhaps contributing to separate them from the multinucleated syncytia. Our findings highlighted the cell-cell interaction and molecular dynamics between hFGCs and (pre)granulosa cells during the formation of primordial follicles in humans. Knowledge on how the pool of primordial follicle is formed is important to understand human infertility.
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Affiliation(s)
- Sylwia M Czukiewska
- https://ror.org/05xvt9f17 Department of Anatomy and Embryology, Leiden University Medical Center, Leiden, Netherlands
| | - Xueying Fan
- https://ror.org/05xvt9f17 Department of Anatomy and Embryology, Leiden University Medical Center, Leiden, Netherlands
| | - Adriaan A Mulder
- https://ror.org/05xvt9f17 Electron Microscopy Facility, Department of Cell and Chemical Biology, Leiden University Medical Center, Leiden, Netherlands
| | - Talia Van Der Helm
- https://ror.org/05xvt9f17 Department of Anatomy and Embryology, Leiden University Medical Center, Leiden, Netherlands
| | - Sanne Hillenius
- https://ror.org/05xvt9f17 Department of Anatomy and Embryology, Leiden University Medical Center, Leiden, Netherlands
| | - Lotte Van Der Meeren
- https://ror.org/05xvt9f17 Department of Pathology, Leiden University Medical Center, Leiden, Netherlands
- Department of Pathology, Erasmus Medical Center, Rotterdam, Netherlands
| | - Roberto Matorras
- IVIRMA, IVI Bilbao, Bilbao, Spain
- Human Reproduction Unit, Cruces University Hospital, Bilbao, Spain
- Department of Obstetrics and Gynecology, Basque Country University, Bilbao, Spain
- Biocruces Bizkaia Health Research Institute, Bilbao, Spain
| | - Cristina Eguizabal
- Cell Therapy, Stem Cells and Tissues Group, Basque Centre for Blood Transfusion and Human Tissues, Galdakao, Spain
- Biocruces Bizkaia Health Research Institute, Barakaldo, Spain
| | - Lei Lei
- Department of Obstetrics, Gynecology and Women's Health, University of Missouri School of Medicine, Columbia, MO, USA
| | - Roman I Koning
- https://ror.org/05xvt9f17 Electron Microscopy Facility, Department of Cell and Chemical Biology, Leiden University Medical Center, Leiden, Netherlands
| | - Susana M Chuva De Sousa Lopes
- https://ror.org/05xvt9f17 Department of Anatomy and Embryology, Leiden University Medical Center, Leiden, Netherlands
- https://ror.org/00xmkp704 Department for Reproductive Medicine, Ghent University Hospital, Ghent, Belgium
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4
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Telfer EE, Grosbois J, Odey YL, Rosario R, Anderson RA. Making a good egg: human oocyte health, aging, and in vitro development. Physiol Rev 2023; 103:2623-2677. [PMID: 37171807 PMCID: PMC10625843 DOI: 10.1152/physrev.00032.2022] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2022] [Revised: 05/03/2023] [Accepted: 05/06/2023] [Indexed: 05/13/2023] Open
Abstract
Mammalian eggs (oocytes) are formed during fetal life and establish associations with somatic cells to form primordial follicles that create a store of germ cells (the primordial pool). The size of this pool is influenced by key events during the formation of germ cells and by factors that influence the subsequent activation of follicle growth. These regulatory pathways must ensure that the reserve of oocytes within primordial follicles in humans lasts for up to 50 years, yet only approximately 0.1% will ever be ovulated with the rest undergoing degeneration. This review outlines the mechanisms and regulatory pathways that govern the processes of oocyte and follicle formation and later growth, within the ovarian stroma, through to ovulation with particular reference to human oocytes/follicles. In addition, the effects of aging on female reproductive capacity through changes in oocyte number and quality are emphasized, with both the cellular mechanisms and clinical implications discussed. Finally, the details of current developments in culture systems that support all stages of follicle growth to generate mature oocytes in vitro and emerging prospects for making new oocytes from stem cells are outlined.
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Affiliation(s)
- Evelyn E Telfer
- Institute of Cell Biology, School of Biological Sciences, University of Edinburgh, Edinburgh, United Kingdom
- Centre for Discovery Brain Sciences, Biomedical Sciences, University of Edinburgh, Edinburgh, United Kingdom
| | - Johanne Grosbois
- Institute of Cell Biology, School of Biological Sciences, University of Edinburgh, Edinburgh, United Kingdom
- Centre for Discovery Brain Sciences, Biomedical Sciences, University of Edinburgh, Edinburgh, United Kingdom
| | - Yvonne L Odey
- Institute of Cell Biology, School of Biological Sciences, University of Edinburgh, Edinburgh, United Kingdom
- Centre for Discovery Brain Sciences, Biomedical Sciences, University of Edinburgh, Edinburgh, United Kingdom
| | - Roseanne Rosario
- Centre for Discovery Brain Sciences, Biomedical Sciences, University of Edinburgh, Edinburgh, United Kingdom
- MRC Centre for Reproductive Health, Queens Medical Research Institute, University of Edinburgh, Edinburgh, United Kingdom
| | - Richard A Anderson
- MRC Centre for Reproductive Health, Queens Medical Research Institute, University of Edinburgh, Edinburgh, United Kingdom
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5
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Mizuta K, Saitou M. Key mechanisms and in vitro reconstitution of fetal oocyte development in mammals. Curr Opin Genet Dev 2023; 82:102091. [PMID: 37556984 DOI: 10.1016/j.gde.2023.102091] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2023] [Revised: 06/23/2023] [Accepted: 07/01/2023] [Indexed: 08/11/2023]
Abstract
During fetal oocyte development in mammals, germ cells progress through meiotic prophase I to form primordial follicles with pregranulosa cells. The primordial follicles remain dormant until oogenesis resumes during puberty. Studies in mice have elucidated mechanisms governing oogenesis, leading to the successful induction of functional oocytes from mouse pluripotent stem cells in vitro. Based on the in vivo/in vitro knowledge in mice and the histological and transcriptomic evidence for fetal oocyte development in humans and primates, human/primate oocyte-like cells corresponding to the early stage of oocytes in vivo have been successfully induced in vitro. Here, we discuss recent advances in our understanding of the mechanisms of fetal oocyte development in mammals, as well as in in vitro oogenesis.
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Affiliation(s)
- Ken Mizuta
- Institute for the Advanced Study of Human Biology (ASHBi), Kyoto University, Yoshida-Konoe-cho, Sakyo-ku, Kyoto 606-8501, Japan; Department of Anatomy and Cell Biology, Graduate School of Medicine, Kyoto University, Yoshida-Konoe-cho, Sakyo-ku, Kyoto 606-8501, Japan.
| | - Mitinori Saitou
- Institute for the Advanced Study of Human Biology (ASHBi), Kyoto University, Yoshida-Konoe-cho, Sakyo-ku, Kyoto 606-8501, Japan; Department of Anatomy and Cell Biology, Graduate School of Medicine, Kyoto University, Yoshida-Konoe-cho, Sakyo-ku, Kyoto 606-8501, Japan; Center for iPS Cell Research and Application (CiRA), Kyoto University, 53 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto 606-8507, Japan.
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Ikami K, Shoffner-Beck S, Tyczynska Weh M, Schnell S, Yoshida S, Diaz Miranda EA, Ko S, Lei L. Branched germline cysts and female-specific cyst fragmentation facilitate oocyte determination in mice. Proc Natl Acad Sci U S A 2023; 120:e2219683120. [PMID: 37155904 PMCID: PMC10194012 DOI: 10.1073/pnas.2219683120] [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: 11/17/2022] [Accepted: 04/03/2023] [Indexed: 05/10/2023] Open
Abstract
During mouse gametogenesis, germ cells derived from the same progenitor are connected via intercellular bridges forming germline cysts, within which asymmetrical or symmetrical cell fate occurs in female and male germ cells, respectively. Here, we have identified branched cyst structures in mice, and investigated their formation and function in oocyte determination. In fetal female cysts, 16.8% of the germ cells are connected by three or four bridges, namely branching germ cells. These germ cells are preferentially protected from cell death and cyst fragmentation and accumulate cytoplasm and organelles from sister germ cells to become primary oocytes. Changes in cyst structure and differential cell volumes among cyst germ cells suggest that cytoplasmic transport in germline cysts is conducted in a directional manner, in which cellular content is first transported locally between peripheral germ cells and further enriched in branching germ cells, a process causing selective germ cell loss in cysts. Cyst fragmentation occurs extensively in female cysts, but not in male cysts. Male cysts in fetal and adult testes have branched cyst structures, without differential cell fates between germ cells. During fetal cyst formation, E-cadherin (E-cad) junctions between germ cells position intercellular bridges to form branched cysts. Disrupted junction formation in E-cad-depleted cysts led to an altered ratio in branched cysts. Germ cell-specific E-cad knockout resulted in reductions in primary oocyte number and oocyte size. These findings shed light on how oocyte fate is determined within mouse germline cysts.
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Affiliation(s)
- Kanako Ikami
- Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, MI48109
- Buck Institute for Research on Aging, Novato, CA94945
| | - Suzanne Shoffner-Beck
- Department of Molecular & Integrative Physiology, University of Michigan Medical School, Ann Arbor, MI48109
| | - Malgorzata Tyczynska Weh
- Department of Molecular & Integrative Physiology, University of Michigan Medical School, Ann Arbor, MI48109
| | - Santiago Schnell
- Department of Molecular & Integrative Physiology, University of Michigan Medical School, Ann Arbor, MI48109
| | - Shosei Yoshida
- Division of Germ Cell Biology, National Institute for Basic Biology, Okazaki, Aichi444-8585, Japan
- Graduate Institute for Advanced Studies, Sokendai, Okazaki, Aichi444-8585, Japan
| | - Edgar Andres Diaz Miranda
- Department of Obstetrics, Gynecology and Women’s Health, University of Missouri School of Medicine, Columbia, MO65211
| | - Sooah Ko
- Department of Obstetrics, Gynecology and Women’s Health, University of Missouri School of Medicine, Columbia, MO65211
| | - Lei Lei
- Department of Obstetrics, Gynecology and Women’s Health, University of Missouri School of Medicine, Columbia, MO65211
- Division of Biological Sciences, College of Arts and Sciences, University of Missouri, Columbia, MO65211
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7
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Spradling AC, Niu W, Yin Q, Pathak M, Maurya B. Conservation of oocyte development in germline cysts from Drosophila to mouse. eLife 2022; 11:83230. [PMID: 36445738 PMCID: PMC9708067 DOI: 10.7554/elife.83230] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2022] [Accepted: 11/17/2022] [Indexed: 11/30/2022] Open
Abstract
Recent studies show that pre-follicular mouse oogenesis takes place in germline cysts, highly conserved groups of oogonial cells connected by intercellular bridges that develop as nurse cells as well as an oocyte. Long studied in Drosophila and insect gametogenesis, female germline cysts acquire cytoskeletal polarity and traffic centrosomes and organelles between nurse cells and the oocyte to form the Balbiani body, a conserved marker of polarity. Mouse oocyte development and nurse cell dumping are supported by dynamic, cell-specific programs of germline gene expression. High levels of perinatal germ cell death in this species primarily result from programmed nurse cell turnover after transfer rather than defective oocyte production. The striking evolutionary conservation of early oogenesis mechanisms between distant animal groups strongly suggests that gametogenesis and early embryonic development in vertebrates and invertebrates share even more in common than currently believed.
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Affiliation(s)
- Allan C Spradling
- Carnegie Institution for Science/Howard Hughes Medical Institute, Baltimore, United States
| | - Wanbao Niu
- Carnegie Institution for Science/Howard Hughes Medical Institute, Baltimore, United States
| | - Qi Yin
- Carnegie Institution for Science/Howard Hughes Medical Institute, Baltimore, United States
| | - Madhulika Pathak
- Carnegie Institution for Science/Howard Hughes Medical Institute, Baltimore, United States
| | - Bhawana Maurya
- Carnegie Institution for Science/Howard Hughes Medical Institute, Baltimore, United States
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8
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Gerhold AR, Labbé JC, Singh R. Uncoupling cell division and cytokinesis during germline development in metazoans. Front Cell Dev Biol 2022; 10:1001689. [PMID: 36407108 PMCID: PMC9669650 DOI: 10.3389/fcell.2022.1001689] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2022] [Accepted: 10/17/2022] [Indexed: 11/06/2022] Open
Abstract
The canonical eukaryotic cell cycle ends with cytokinesis, which physically divides the mother cell in two and allows the cycle to resume in the newly individualized daughter cells. However, during germline development in nearly all metazoans, dividing germ cells undergo incomplete cytokinesis and germ cells stay connected by intercellular bridges which allow the exchange of cytoplasm and organelles between cells. The near ubiquity of incomplete cytokinesis in animal germ lines suggests that this is an ancient feature that is fundamental for the development and function of this tissue. While cytokinesis has been studied for several decades, the mechanisms that enable regulated incomplete cytokinesis in germ cells are only beginning to emerge. Here we review the current knowledge on the regulation of germ cell intercellular bridge formation, focusing on findings made using mouse, Drosophila melanogaster and Caenorhabditis elegans as experimental systems.
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Affiliation(s)
- Abigail R. Gerhold
- Department of Biology, McGill University, Montréal, QC, Canada
- *Correspondence: Abigail R. Gerhold, ; Jean-Claude Labbé,
| | - Jean-Claude Labbé
- Institute for Research in Immunology and Cancer (IRIC), Montréal, QC, Canada
- Department of Pathology and Cell Biology, Université de Montréal, Succ. Centre-ville, Montréal, QC, Canada
- *Correspondence: Abigail R. Gerhold, ; Jean-Claude Labbé,
| | - Ramya Singh
- Department of Biology, McGill University, Montréal, QC, Canada
- Institute for Research in Immunology and Cancer (IRIC), Montréal, QC, Canada
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9
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Niu W, Spradling AC. Mouse oocytes develop in cysts with the help of nurse cells. Cell 2022; 185:2576-2590.e12. [PMID: 35623357 DOI: 10.1016/j.cell.2022.05.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Revised: 03/07/2022] [Accepted: 05/02/2022] [Indexed: 10/18/2022]
Abstract
Mouse germline cysts, on average, develop into six oocytes supported by 24 nurse cells that transfer cytoplasm and organelles to generate a Balbiani body. We showed that between E14.5 and P5, cysts periodically activate some nurse cells to begin cytoplasmic transfer, which causes them to shrink and turnover within 2 days. Nurse cells die by a programmed cell death (PCD) pathway involving acidification, similar to Drosophila nurse cells, and only infrequently by apoptosis. Prior to initiating transfer, nurse cells co-cluster by scRNA-seq with their pro-oocyte sisters, but during their final 2 days, they cluster separately. The genes promoting oocyte development and nurse cell PCD are upregulated, whereas the genes that repress transfer, such as Tex14, and oocyte factors, such as Nobox and Lhx8, are under-expressed. The transferred nurse cell centrosomes build a cytocentrum that establishes a large microtubule aster in the primordial oocyte that organizes the Balbiani body, defining the earliest oocyte polarity.
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Affiliation(s)
- Wanbao Niu
- Howard Hughes Medical Institute Research Laboratories, Department of Embryology, Carnegie Institution for Science, Baltimore, MD 21218, USA
| | - Allan C Spradling
- Howard Hughes Medical Institute Research Laboratories, Department of Embryology, Carnegie Institution for Science, Baltimore, MD 21218, USA.
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10
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Abstract
In vitro systems capable of reconstituting the process of mouse oogenesis are now being established to help develop further understanding of the mechanisms underlying oocyte/follicle development and differentiation. These systems could also help increase the production of useful livestock or genetically modified animals, and aid in identifying the causes of infertility in humans. Recently, we revealed, using an in vitro system for recapitulating oogenesis, that the activation of the estrogen signaling pathway induces abnormal follicle formation, that blocking estrogen-induced expression of anti-Müllerian hormone is crucial for normal follicle formation, and that the production of α-fetoprotein in fetal liver tissue is involved in normal in vivo follicle formation. In mouse fetuses, follicle formation is not carried out by factors within the ovaries but is instead orchestrated by distal endocrine factors. This review outlines findings from genetics, endocrinology, and in vitro studies regarding the factors that can affect the formation of primordial follicles in mammals.
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