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Benner L, Muron S, Gomez JG, Oliver B. OVO Positively Regulates Essential Maternal Pathways by Binding Near the Transcriptional Start Sites in the Drosophila Female Germline. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.11.01.565184. [PMID: 38076814 PMCID: PMC10705541 DOI: 10.1101/2023.11.01.565184] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/25/2023]
Abstract
Differentiation of female germline stem cells into a mature oocyte includes the expression of RNAs and proteins that drive early embryonic development in Drosophila. We have little insight into what activates the expression of these maternal factors. One candidate is the zinc-finger protein OVO. OVO is required for female germline viability and has been shown to positively regulate its own expression, as well as a downstream target, ovarian tumor, by binding to the transcriptional start site (TSS). To find additional OVO targets in the female germline and further elucidate OVO's role in oocyte development, we performed ChIP-seq to determine genome-wide OVO occupancy, as well as RNA-seq comparing hypomorphic and wild type rescue ovo alleles. OVO preferentially binds in close proximity to target TSSs genome-wide, is associated with open chromatin, transcriptionally active histone marks, and OVO-dependent expression. Motif enrichment analysis on OVO ChIP peaks identified a 5'-TAACNGT-3' OVO DNA binding motif spatially enriched near TSSs. However, the OVO DNA binding motif does not exhibit precise motif spacing relative to the TSS characteristic of RNA Polymerase II complex binding core promoter elements. Integrated genomics analysis showed that 525 genes that are bound and increase in expression downstream of OVO are known to be essential maternally expressed genes. These include genes involved in anterior/posterior/germ plasm specification (bcd, exu, swa, osk, nos, aub, pgc, gcl), egg activation (png, plu, gnu, wisp, C(3)g, mtrm), translational regulation (cup, orb, bru1, me31B), and vitelline membrane formation (fs(1)N, fs(1)M3, clos). This suggests that OVO is a master transcriptional regulator of oocyte development and is responsible for the expression of structural components of the egg as well as maternally provided RNAs that are required for early embryonic development.
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Affiliation(s)
- Leif Benner
- Section of Developmental Genomics, Laboratory of Biochemistry and Genetics, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD, USA
- Department of Biology, Johns Hopkins University, Baltimore, MD, USA
| | - Savannah Muron
- Section of Developmental Genomics, Laboratory of Biochemistry and Genetics, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Jillian G Gomez
- Section of Developmental Genomics, Laboratory of Biochemistry and Genetics, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Brian Oliver
- Section of Developmental Genomics, Laboratory of Biochemistry and Genetics, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD, USA
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2
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Hannaford MR, Rusan NM. Positioning centrioles and centrosomes. J Cell Biol 2024; 223:e202311140. [PMID: 38512059 PMCID: PMC10959756 DOI: 10.1083/jcb.202311140] [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: 12/14/2023] [Revised: 02/23/2024] [Accepted: 02/26/2024] [Indexed: 03/22/2024] Open
Abstract
Centrosomes are the primary microtubule organizer in eukaryotic cells. In addition to shaping the intracellular microtubule network and the mitotic spindle, centrosomes are responsible for positioning cilia and flagella. To fulfill these diverse functions, centrosomes must be properly located within cells, which requires that they undergo intracellular transport. Importantly, centrosome mispositioning has been linked to ciliopathies, cancer, and infertility. The mechanisms by which centrosomes migrate are diverse and context dependent. In many cells, centrosomes move via indirect motor transport, whereby centrosomal microtubules engage anchored motor proteins that exert forces on those microtubules, resulting in centrosome movement. However, in some cases, centrosomes move via direct motor transport, whereby the centrosome or centriole functions as cargo that directly binds molecular motors which then walk on stationary microtubules. In this review, we summarize the mechanisms of centrosome motility and the consequences of centrosome mispositioning and identify key questions that remain to be addressed.
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Affiliation(s)
- Matthew R. Hannaford
- Cell and Developmental Biology Center, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD, USA
| | - Nasser M. Rusan
- Cell and Developmental Biology Center, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD, USA
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3
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Gomez A, Gonzalez S, Oke A, Luo J, Duong JB, Esquerra RM, Zimmerman T, Capponi S, Fung JC, Nystul TG. A high-throughput method for quantifying Drosophila fecundity. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.03.27.587093. [PMID: 38585877 PMCID: PMC10996622 DOI: 10.1101/2024.03.27.587093] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/09/2024]
Abstract
Measurements of Drosophila fecundity are used in a wide variety of studies, such as investigations of stem cell biology, nutrition, behavior, and toxicology. In addition, because fecundity assays are performed on live flies, they are suitable for longitudinal studies such as investigations of aging or prolonged chemical exposure. However, standard Drosophila fecundity assays have been difficult to perform in a high-throughput manner because experimental factors such as the physiological state of the flies and environmental cues must be carefully controlled to achieve consistent results. In addition, exposing flies to a large number of different experimental conditions (such as chemical additives in the diet) and manually counting the number of eggs laid to determine the impact on fecundity is time-consuming. We have overcome these challenges by combining a new multiwell fly culture strategy with a novel 3D-printed fly transfer device to rapidly and accurately transfer flies from one plate to another; the RoboCam, a low-cost, custom built robotic camera to capture images of the wells automatically; and an image segmentation pipeline to automatically identify and quantify eggs. We show that this method is compatible with robust and consistent egg laying throughout the assay period; and demonstrate that the automated pipeline for quantifying fecundity is very accurate (r2 = 0.98 for the correlation between the automated egg counts and the ground truth) In addition, we show that this method can be used to efficiently detect the effects on fecundity induced by dietary exposure to chemicals. Taken together, this strategy substantially increases the efficiency and reproducibility of high throughput egg laying assays that require exposing flies to multiple different media conditions.
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Affiliation(s)
- Andreana Gomez
- University of California, San Francisco, Department of Anatomy
| | - Sergio Gonzalez
- San Francisco State University, Department of Biology
- Center for Cellular Construction, San Francisco, CA
| | - Ashwini Oke
- San Francisco State University, Department of Chemistry and Biochemistry; University of California, San Francisco, OB/GYN Department
- IBM Almaden Research Center, San Jose, CA; University of California, San Francisco, Center for Reproductive Sciences
| | - Jiayu Luo
- San Francisco State University, Department of Biology
- Center for Cellular Construction, San Francisco, CA
| | - Johnny B Duong
- Center for Cellular Construction, San Francisco, CA
- San Francisco State University, Department of Chemistry and Biochemistry; University of California, San Francisco, OB/GYN Department
| | - Raymond M Esquerra
- Center for Cellular Construction, San Francisco, CA
- San Francisco State University, Department of Chemistry and Biochemistry; University of California, San Francisco, OB/GYN Department
| | - Thomas Zimmerman
- Center for Cellular Construction, San Francisco, CA
- IBM Almaden Research Center, San Jose, CA; University of California, San Francisco, Center for Reproductive Sciences
| | - Sara Capponi
- Center for Cellular Construction, San Francisco, CA
- IBM Almaden Research Center, San Jose, CA; University of California, San Francisco, Center for Reproductive Sciences
| | - Jennifer C Fung
- San Francisco State University, Department of Chemistry and Biochemistry; University of California, San Francisco, OB/GYN Department
- IBM Almaden Research Center, San Jose, CA; University of California, San Francisco, Center for Reproductive Sciences
- University of California, San Francisco EaRTH Center
| | - Todd G Nystul
- University of California, San Francisco, Department of Anatomy
- San Francisco State University, Department of Chemistry and Biochemistry; University of California, San Francisco, OB/GYN Department
- IBM Almaden Research Center, San Jose, CA; University of California, San Francisco, Center for Reproductive Sciences
- University of California, San Francisco EaRTH Center
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4
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Spradling AC. The Ancient Origin and Function of Germline Cysts. Results Probl Cell Differ 2024; 71:3-21. [PMID: 37996670 DOI: 10.1007/978-3-031-37936-9_1] [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
Gamete production in most animal species is initiated within an evolutionarily ancient multicellular germline structure, the germline cyst, whose interconnected premeiotic cells synchronously develop from a single progenitor arising just downstream from a stem cell. Cysts in mice, Drosophila, and many other animals protect developing sperm, while in females, cysts generate nurse cells that guard sister oocytes from transposons (TEs) and help them grow and build a Balbiani body. However, the origin and extreme evolutionary conservation of germline cysts remains a mystery. We suggest that cysts arose in ancestral animals like Hydra and Planaria whose multipotent somatic and germline stem cells (neoblasts) express genes conserved in all animal germ cells and frequently begin differentiation in cysts. A syncytial state is proposed to help multipotent stem cell chromatin transition to an epigenetic state with heterochromatic domains suitable for TE repression and specialized function. Most modern animals now lack neoblasts but have retained stem cells and cysts in their early germlines, which continue to function using this ancient epigenetic strategy.
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Affiliation(s)
- Allan C Spradling
- Carnegie Institution for Science/Howard Hughes Medical Institute, Baltimore, MD, USA.
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5
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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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Kloc M, Tworzydło W, Szklarzewicz T. Germline and Somatic Cell Syncytia in Insects. Results Probl Cell Differ 2024; 71:47-63. [PMID: 37996672 DOI: 10.1007/978-3-031-37936-9_3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2023]
Abstract
Syncytia are common in the animal and plant kingdoms both under normal and pathological conditions. They form through cell fusion or division of a founder cell without cytokinesis. A particular type of syncytia occurs in invertebrate and vertebrate gametogenesis when the founder cell divides several times with partial cytokinesis producing a cyst (nest) of germ line cells connected by cytoplasmic bridges. The ultimate destiny of the cyst's cells differs between animal groups. Either all cells of the cyst become the gametes or some cells endoreplicate or polyploidize to become the nurse cells (trophocytes). Although many types of syncytia are permanent, the germ cell syncytium is temporary, and eventually, it separates into individual gametes. In this chapter, we give an overview of syncytium types and focus on the germline and somatic cell syncytia in various groups of insects. We also describe the multinuclear giant cells, which form through repetitive nuclear divisions and cytoplasm hypertrophy, but without cell fusion, and the accessory nuclei, which bud off the oocyte nucleus, migrate to its cortex and become included in the early embryonic syncytium.
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Affiliation(s)
- Malgorzata Kloc
- The Houston Methodist Research Institute, Houston, TX, USA.
- The Houston Methodist Hospital, Department of Surgery, Houston, TX, USA.
- Department of Genetics, MD Anderson Cancer Center, The University of Texas, Houston, TX, USA.
| | - Wacław Tworzydło
- Department of Developmental Biology and Invertebrate Morphology, Institute of Zoology and Biomedical Research, Faculty of Biology, Jagiellonian University in Krakow, Krakow, Poland
| | - Teresa Szklarzewicz
- Department of Developmental Biology and Invertebrate Morphology, Institute of Zoology and Biomedical Research, Faculty of Biology, Jagiellonian University in Krakow, Krakow, Poland
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7
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Klutstein M, Gonen N. Epigenetic aging of mammalian gametes. Mol Reprod Dev 2023; 90:785-803. [PMID: 37997675 DOI: 10.1002/mrd.23717] [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: 12/18/2022] [Revised: 11/09/2023] [Accepted: 11/12/2023] [Indexed: 11/25/2023]
Abstract
The process of aging refers to physiological changes that occur to an organism as time progresses and involves changes to DNA, proteins, metabolism, cells, and organs. Like the rest of the cells in the body, gametes age, and it is well established that there is a decline in reproductive capabilities in females and males with aging. One of the major pathways known to be involved in aging is epigenetic changes. The epigenome is the multitude of chemical modifications performed on DNA and chromatin that affect the ability of chromatin to be transcribed. In this review, we explore the effects of aging on female and male gametes with a focus on the epigenetic changes that occur in gametes throughout aging. Quality decline in oocytes occurs at a relatively early age. Epigenetic changes constitute an important part of oocyte aging. DNA methylation is reduced with age, along with reduced expression of DNA methyltransferases (DNMTs). Histone deacetylases (HDAC) expression is also reduced, and a loss of heterochromatin marks occurs with age. As a consequence of heterochromatin loss, retrotransposon expression is elevated, and aged oocytes suffer from DNA damage. In sperm, aging affects sperm number, motility and fecundity, and epigenetic changes may constitute a part of this process. 5 methyl-cytosine (5mC) methylation is elevated in sperm from aged men, but methylation on Long interspersed nuclear elements (LINE) elements is reduced. Di and trimethylation of histone 3 lysine 9 (H3K9me2/3) is reduced in sperm from aged men and trimethylation of histone 3 lysine 27 (H3K27me3) is elevated. The protamine makeup of sperm from aged men is also changed, with reduced protamine expression and a misbalanced ratio between protamine proteins protamine P1 and protamine P2. The study of epigenetic reproductive aging is recently gaining interest. The current status of the field suggests that many aspects of gamete epigenetic aging are still open for investigation. The clinical applications of these investigations have far-reaching consequences for fertility and sociological human behavior.
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Affiliation(s)
- Michael Klutstein
- Institute of Biomedical and Oral Research, Faculty of Dental Medicine, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Nitzan Gonen
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan, Israel
- Institute of Nanotechnology and Advanced Materials, Bar-Ilan University, Ramat Gan, Israel
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8
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Glynos A, Bozhilova LV, Frison M, Burr S, Stewart JB, Chinnery PF. High-throughput single-cell analysis reveals progressive mitochondrial DNA mosaicism throughout life. SCIENCE ADVANCES 2023; 9:eadi4038. [PMID: 37878704 PMCID: PMC10599618 DOI: 10.1126/sciadv.adi4038] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/24/2023] [Accepted: 09/21/2023] [Indexed: 10/27/2023]
Abstract
Heteroplasmic mitochondrial DNA (mtDNA) mutations are a major cause of inherited disease and contribute to common late-onset human disorders. The late onset and clinical progression of mtDNA-associated disease is thought to be due to changing heteroplasmy levels, but it is not known how and when this occurs. Performing high-throughput single-cell genotyping in two mouse models of human mtDNA disease, we saw unanticipated cell-to-cell differences in mtDNA heteroplasmy levels that emerged prenatally and progressively increased throughout life. Proliferating spleen cells and nondividing brain cells had a similar single-cell heteroplasmy variance, implicating mtDNA or organelle turnover as the major force determining cell heteroplasmy levels. The two different mtDNA mutations segregated at different rates with no evidence of selection, consistent with different rates of random genetic drift in vivo, leading to the accumulation of cells with a very high mutation burden at different rates. This provides an explanation for differences in severity seen in human diseases caused by similar mtDNA mutations.
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Affiliation(s)
- Angelos Glynos
- Department of Clinical Neurosciences, School of Clinical Medicine, University of Cambridge, Cambridge Biomedical Campus, Cambridge, UK
- Medical Research Council Mitochondrial Biology Unit, University of Cambridge, Cambridge Biomedical Campus, Cambridge, UK
| | - Lyuba V. Bozhilova
- Department of Clinical Neurosciences, School of Clinical Medicine, University of Cambridge, Cambridge Biomedical Campus, Cambridge, UK
- Medical Research Council Mitochondrial Biology Unit, University of Cambridge, Cambridge Biomedical Campus, Cambridge, UK
| | - Michele Frison
- Department of Clinical Neurosciences, School of Clinical Medicine, University of Cambridge, Cambridge Biomedical Campus, Cambridge, UK
- Medical Research Council Mitochondrial Biology Unit, University of Cambridge, Cambridge Biomedical Campus, Cambridge, UK
| | - Stephen Burr
- Department of Clinical Neurosciences, School of Clinical Medicine, University of Cambridge, Cambridge Biomedical Campus, Cambridge, UK
- Medical Research Council Mitochondrial Biology Unit, University of Cambridge, Cambridge Biomedical Campus, Cambridge, UK
| | - James B. Stewart
- Biosciences Institute, Faculty of Medical Sciences, Wellcome Centre for Mitochondrial Research, Newcastle University, Newcastle upon Tyne, UK
| | - Patrick F. Chinnery
- Department of Clinical Neurosciences, School of Clinical Medicine, University of Cambridge, Cambridge Biomedical Campus, Cambridge, UK
- Medical Research Council Mitochondrial Biology Unit, University of Cambridge, Cambridge Biomedical Campus, Cambridge, UK
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9
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Lanz MC, Zhang S, Swaffer MP, Hernández Götz L, McCarty F, Ziv I, Jarosz DF, Elias JE, Skotheim JM. Genome dilution by cell growth drives starvation-like proteome remodeling in mammalian and yeast cells. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.10.16.562558. [PMID: 37905015 PMCID: PMC10614910 DOI: 10.1101/2023.10.16.562558] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/02/2023]
Abstract
Cell size is tightly controlled in healthy tissues and single-celled organisms, but it remains unclear how size influences cell physiology. Increasing cell size was recently shown to remodel the proteomes of cultured human cells, demonstrating that large and small cells of the same type can be biochemically different. Here, we corroborate these results in mouse hepatocytes and extend our analysis using yeast. We find that size-dependent proteome changes are highly conserved and mostly independent of metabolic state. As eukaryotic cells grow larger, the dilution of the genome elicits a starvation-like proteome phenotype, suggesting that growth in large cells is limited by the genome in a manner analogous to a limiting nutrient. We also demonstrate that the proteomes of replicatively-aged yeast are primarily determined by their large size. Overall, our data suggest that genome concentration is a universal determinant of proteome content in growing cells.
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10
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Pang LY, DeLuca S, Zhu H, Urban JM, Spradling AC. Chromatin and gene expression changes during female Drosophila germline stem cell development illuminate the biology of highly potent stem cells. eLife 2023; 12:RP90509. [PMID: 37831064 PMCID: PMC10575629 DOI: 10.7554/elife.90509] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2023] Open
Abstract
Highly potent animal stem cells either self renew or launch complex differentiation programs, using mechanisms that are only partly understood. Drosophila female germline stem cells (GSCs) perpetuate without change over evolutionary time and generate cystoblast daughters that develop into nurse cells and oocytes. Cystoblasts initiate differentiation by generating a transient syncytial state, the germline cyst, and by increasing pericentromeric H3K9me3 modification, actions likely to suppress transposable element activity. Relatively open GSC chromatin is further restricted by Polycomb repression of testis or somatic cell-expressed genes briefly active in early female germ cells. Subsequently, Neijre/CBP and Myc help upregulate growth and reprogram GSC metabolism by altering mitochondrial transmembrane transport, gluconeogenesis, and other processes. In all these respects GSC differentiation resembles development of the totipotent zygote. We propose that the totipotent stem cell state was shaped by the need to resist transposon activity over evolutionary timescales.
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Affiliation(s)
- Liang-Yu Pang
- Howard Hughes Medical Institute, Carnegie Institution for ScienceBaltimoreUnited States
| | - Steven DeLuca
- Howard Hughes Medical Institute, Carnegie Institution for ScienceBaltimoreUnited States
| | - Haolong Zhu
- Howard Hughes Medical Institute, Carnegie Institution for ScienceBaltimoreUnited States
| | - John M Urban
- Howard Hughes Medical Institute, Carnegie Institution for ScienceBaltimoreUnited States
| | - Allan C Spradling
- Howard Hughes Medical Institute, Carnegie Institution for ScienceBaltimoreUnited States
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11
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Hu M, Schultz RM, Namekawa SH. Epigenetic programming in the ovarian reserve. Bioessays 2023; 45:e2300069. [PMID: 37417392 PMCID: PMC10698196 DOI: 10.1002/bies.202300069] [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: 04/18/2023] [Revised: 06/02/2023] [Accepted: 06/27/2023] [Indexed: 07/08/2023]
Abstract
The ovarian reserve defines female reproductive lifespan, which in humans spans decades. The ovarian reserve consists of oocytes residing in primordial follicles arrested in meiotic prophase I and is maintained independent of DNA replication and cell proliferation, thereby lacking stem cell-based maintenance. Largely unknown is how cellular states of the ovarian reserve are established and maintained for decades. Our recent study revealed that a distinct chromatin state is established during ovarian reserve formation in mice, uncovering a novel window of epigenetic programming in female germline development. We showed that an epigenetic regulator, Polycomb Repressive Complex 1 (PRC1), establishes a repressive chromatin state in perinatal mouse oocytes that is essential for prophase I-arrested oocytes to form the ovarian reserve. Here we discuss the biological roles and mechanisms underlying epigenetic programming in ovarian reserve formation, highlighting current knowledge gaps and emerging research areas in female reproductive biology.
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Affiliation(s)
- Mengwen Hu
- Department of Microbiology and Molecular Genetics, University of California, Davis, California, USA
| | - Richard M. Schultz
- Department of Biology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
- Department of Anatomy, Physiology and Cell Biology, School of Veterinary Medicine, University of California, Davis, California, USA
| | - Satoshi H. Namekawa
- Department of Microbiology and Molecular Genetics, University of California, Davis, California, USA
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12
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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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13
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Cabrita B, Martinho RG. Genetic and Epigenetic Regulation of Drosophila Oocyte Determination. J Dev Biol 2023; 11:21. [PMID: 37367475 DOI: 10.3390/jdb11020021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Revised: 05/18/2023] [Accepted: 05/20/2023] [Indexed: 06/28/2023] Open
Abstract
Primary oocyte determination occurs in many organisms within a germ line cyst, a multicellular structure composed of interconnected germ cells. However, the structure of the cyst is itself highly diverse, which raises intriguing questions about the benefits of this stereotypical multicellular environment for female gametogenesis. Drosophila melanogaster is a well-studied model for female gametogenesis, and numerous genes and pathways critical for the determination and differentiation of a viable female gamete have been identified. This review provides an up-to-date overview of Drosophila oocyte determination, with a particular emphasis on the mechanisms that regulate germ line gene expression.
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Affiliation(s)
- Brigite Cabrita
- Department of Medical Sciences, Institute of Biomedicine (iBiMED), University of Aveiro, Agra do Crasto, Edifício 30, 3810-193 Aveiro, Portugal
| | - Rui Gonçalo Martinho
- Department of Medical Sciences, Institute of Biomedicine (iBiMED), University of Aveiro, Agra do Crasto, Edifício 30, 3810-193 Aveiro, Portugal
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14
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Derdak A, Jędrzejowska I, Mąkol J. An overview of chelicerate ovaries, with special reference to mites - myths and facts. Micron 2023; 167:103417. [PMID: 36773594 DOI: 10.1016/j.micron.2023.103417] [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: 10/24/2022] [Revised: 01/20/2023] [Accepted: 01/21/2023] [Indexed: 01/23/2023]
Abstract
In arthropods of the subphylum Chelicerata a panoistic ovary, in which all germline cells differentiate into oocytes, prevails. Among the chelicerates, mites are believed to show a great variety of the structure of the female gonads. In general, the knowledge of the ovarian structure in mites is fragmentary and patchy. In both evolutionary lines, Acariformes and Parasitiformes, apart from the panoistic ovary, the meroistic ovary, in which the oocytes grow supported by their sibling cells, the nurse cells, occurs. The presence of the meroistic ovary is considered an apomorphic state. Previous studies revealed a various structure of the meroistic ovary in different mite taxa, and the differences came down, inter alia, to a different number and location of the nurse cells in relation to the oocytes. Here we provide a comprehensive review of the structure of the Chelicerata ovary, with special reference to the mite ovary. We also provide our preliminary results of the analysis of ovarian structure in two representatives of terrestrial Parasitengona (Acariformes), Allothrombium fuliginosum (Trombidiidae) and Erythraeus cinereus (Erythraeidae), performed using light, confocal and electron transmission microscopy. The analyses allowed for verification of data published before. In A. fuliginosum we showed the presence of the nurse cells in the ovarian wall, so the ovary should be classified as meroistic. In meroistic ovary of E. cinereus we found that each oocyte is connected to several mononucleated nurse cells. The verification of literature data and broadening the knowledge of the structure of the female gonad in mites, will result in estimating the usefulness of the ovary traits in phylogenetic analyses and will provide the basis for inference about the directions of evolutionary changes of female gonad at lower systematic levels.
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Affiliation(s)
- Anna Derdak
- Department of Animal Developmental Biology, University of Wroclaw, Sienkiewicza 21, 50-335 Wrocław, Poland,.
| | - Izabela Jędrzejowska
- Department of Animal Developmental Biology, University of Wroclaw, Sienkiewicza 21, 50-335 Wrocław, Poland
| | - Joanna Mąkol
- Department of Invertebrate Systematics and Ecology, Wroclaw University of Environmental and Life Sciences, Kożuchowska 5b, 51-631 Wrocław, Poland
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