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Wood TW, Henriques WS, Cullen HB, Romero M, Blengini CS, Sarathy S, Sorkin J, Bekele H, Jin C, Kim S, Chemiakine A, Khondker RC, Isola JV, Stout MB, Gennarino VA, Mogessie B, Jain D, Schindler K, Suh Y, Wiedenheft B, Berchowitz LE. The retrotransposon-derived capsid genes PNMA1 and PNMA4 maintain reproductive capacity. RESEARCH SQUARE 2024:rs.3.rs-4559920. [PMID: 39041030 PMCID: PMC11261967 DOI: 10.21203/rs.3.rs-4559920/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/24/2024]
Abstract
The human genome contains 24 gag-like capsid genes derived from deactivated retrotransposons conserved among eutherians. Although some of their encoded proteins retain the ability to form capsids and even transfer cargo, their fitness benefit has remained elusive. Here we show that the gag-like genes PNMA1 and PNMA4 support reproductive capacity during aging. Analysis of donated human ovaries shows that expression of both genes declines normally with age, while several PNMA1 and PNMA4 variants identified in genome-wide association studies are causally associated with low testosterone, altered puberty onset, or obesity. Six-week-old mice lacking either Pnma1 or Pnma4 are indistinguishable from wild-type littermates, but by six months the mutant mice become prematurely subfertile, with precipitous drops in sex hormone levels, gonadal atrophy, and abdominal obesity; overall they produce markedly fewer offspring than controls. These findings expand our understanding of factors that maintain human reproductive health and lend insight into the domestication of retrotransposon-derived genes.
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Affiliation(s)
- Thomas W.P. Wood
- Department of Genetics and Development, Columbia University Irving Medical Center, New York, NY 10032, USA
| | - William S. Henriques
- Department of Microbiology and Cell Biology, Montana State University, Bozeman, MT, 59717, USA
| | - Harrison B. Cullen
- Department of Genetics and Development, Columbia University Irving Medical Center, New York, NY 10032, USA
| | - Mayra Romero
- Department of Genetics, Human Genetics Institute of New Jersey, Rutgers University, 145 Bevier Road, Piscataway, NJ 08854, USA
| | - Cecilia S. Blengini
- Department of Genetics, Human Genetics Institute of New Jersey, Rutgers University, 145 Bevier Road, Piscataway, NJ 08854, USA
| | - Shreya Sarathy
- Department of Genetics, Human Genetics Institute of New Jersey, Rutgers University, 145 Bevier Road, Piscataway, NJ 08854, USA
| | - Julia Sorkin
- Department of Genetics, Human Genetics Institute of New Jersey, Rutgers University, 145 Bevier Road, Piscataway, NJ 08854, USA
| | - Hilina Bekele
- Department of Molecular, Cellular and Developmental Biology, Yale University, New Haven, CT, 06511, USA
| | - Chen Jin
- Department of Obstetrics and Gynecology, Columbia University Irving Medical Center, New York, NY 10032, USA
| | - Seungsoo Kim
- Department of Obstetrics and Gynecology, Columbia University Irving Medical Center, New York, NY 10032, USA
| | - Alexei Chemiakine
- Department of Genetics and Development, Columbia University Irving Medical Center, New York, NY 10032, USA
| | - Rishad C. Khondker
- Department of Genetics and Development, Columbia University Irving Medical Center, New York, NY 10032, USA
| | - José V.V. Isola
- Aging & Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, USA
| | - Michael B. Stout
- Aging & Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, USA
| | - Vincenzo A. Gennarino
- Department of Genetics and Development, Columbia University Irving Medical Center, New York, NY 10032, USA
- Columbia Stem Cell Initiative, New York, NY 10032, USA
- Initiative for Columbia Ataxia and Tremor, New York, NY 10032, USA
| | - Binyam Mogessie
- Department of Molecular, Cellular and Developmental Biology, Yale University, New Haven, CT, 06511, USA
| | - Devanshi Jain
- Department of Genetics, Human Genetics Institute of New Jersey, Rutgers University, 145 Bevier Road, Piscataway, NJ 08854, USA
| | - Karen Schindler
- Department of Genetics, Human Genetics Institute of New Jersey, Rutgers University, 145 Bevier Road, Piscataway, NJ 08854, USA
| | - Yousin Suh
- Department of Genetics and Development, Columbia University Irving Medical Center, New York, NY 10032, USA
- Department of Obstetrics and Gynecology, Columbia University Irving Medical Center, New York, NY 10032, USA
| | - Blake Wiedenheft
- Department of Microbiology and Cell Biology, Montana State University, Bozeman, MT, 59717, USA
| | - Luke E. Berchowitz
- Department of Genetics and Development, Columbia University Irving Medical Center, New York, NY 10032, USA
- Taub Institute for Research on Alzheimer’s and the Aging Brain, New York, NY, USA
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2
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Wood TWP, Henriques WS, Cullen HB, Romero M, Blengini CS, Sarathy S, Sorkin J, Bekele H, Jin C, Kim S, Chemiakine A, Khondker RC, Isola JVV, Stout MB, Gennarino VA, Mogessie B, Jain D, Schindler K, Suh Y, Wiedenheft B, Berchowitz LE. The retrotransposon - derived capsid genes PNMA1 and PNMA4 maintain reproductive capacity. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.05.11.592987. [PMID: 38798495 PMCID: PMC11118267 DOI: 10.1101/2024.05.11.592987] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2024]
Abstract
The human genome contains 24 gag -like capsid genes derived from deactivated retrotransposons conserved among eutherians. Although some of their encoded proteins retain the ability to form capsids and even transfer cargo, their fitness benefit has remained elusive. Here we show that the gag -like genes PNMA1 and PNMA4 support reproductive capacity. Six-week-old mice lacking either Pnma1 or Pnma4 are indistinguishable from wild-type littermates, but by six months the mutant mice become prematurely subfertile, with precipitous drops in sex hormone levels, gonadal atrophy, and abdominal obesity; overall they produce markedly fewer offspring than controls. Analysis of donated human ovaries shows that expression of both genes declines normally with aging, while several PNMA1 and PNMA4 variants identified in genome-wide association studies are causally associated with low testosterone, altered puberty onset, or obesity. These findings expand our understanding of factors that maintain human reproductive health and lend insight into the domestication of retrotransposon-derived genes.
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3
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Yao X, Wang C, Yu W, Sun L, Lv Z, Xie X, Tian S, Yan L, Li L, Liu J. BCAS2 regulates oocyte meiotic prophase I by participating in mRNA alternative splicing. FASEB J 2024; 38:e23361. [PMID: 38085152 DOI: 10.1096/fj.202301234rr] [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: 06/19/2023] [Revised: 11/16/2023] [Accepted: 11/27/2023] [Indexed: 12/18/2023]
Abstract
Oocyte meiotic prophase I (MI) is an important event in female reproduction. Breast cancer amplified sequence 2 (BCAS2) is a component of the spliceosome. Previous reports have shown that BCAS2 is critical in male germ cell meiosis, oocyte development, and early embryo genome integrity. However, the role of BCAS2 in oocyte meiosis has not been reported. We used Stra8-GFPCre mice to knock out Bcas2 in oocytes during the pachytene phase. The results of fertility tests showed that Bcas2 conditional knockout (cKO) in oocytes results in infertility in female mice. Morphological analysis showed that the number of primordial follicles in the ovaries of 2-month-old (M) mice was significantly reduced and that follicle development was blocked. Further analysis showed that the number of primordial follicles decreased and that follicle development was slowed in 7-day postpartum (dpp) ovaries. Moreover, primordial follicles undergo apoptosis, and DNA damage cannot be repaired in primary follicle oocytes. Meiosis was abnormal; some oocytes could not reach the diplotene stage, and more oocytes could not develop to the dictyotene stage. Alternative splicing (AS) analysis revealed abnormal AS of deleted in azoospermia like (Dazl) and diaphanous related formin 2 (Diaph2) oogenesis-related genes in cKO mouse ovaries, and the process of AS was involved by CDC5L and PRP19.
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Affiliation(s)
- Xiaohong Yao
- State Key Laboratory of Animal Biotech Breeding, College of Biological Sciences, China Agricultural University, Beijing, China
| | - Chaofan Wang
- State Key Laboratory of Animal Biotech Breeding, College of Biological Sciences, China Agricultural University, Beijing, China
| | - Weiran Yu
- State Key Laboratory of Animal Biotech Breeding, College of Biological Sciences, China Agricultural University, Beijing, China
| | - Longjie Sun
- State Key Laboratory of Animal Biotech Breeding, College of Biological Sciences, China Agricultural University, Beijing, China
| | - Zheng Lv
- State Key Laboratory of Animal Biotech Breeding, College of Biological Sciences, China Agricultural University, Beijing, China
| | - Xiaomei Xie
- State Key Laboratory of Animal Biotech Breeding, College of Biological Sciences, China Agricultural University, Beijing, China
| | - Shuang Tian
- State Key Laboratory of Animal Biotech Breeding, College of Biological Sciences, China Agricultural University, Beijing, China
| | - Lu Yan
- State Key Laboratory of Animal Biotech Breeding, College of Biological Sciences, China Agricultural University, Beijing, China
| | - Lei Li
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
| | - Jiali Liu
- State Key Laboratory of Animal Biotech Breeding, College of Biological Sciences, China Agricultural University, Beijing, China
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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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Abstract
In meiosis, homologous chromosome synapsis is mediated by a supramolecular protein structure, the synaptonemal complex (SC), that assembles between homologous chromosome axes. The mammalian SC comprises at least eight largely coiled-coil proteins that interact and self-assemble to generate a long, zipper-like structure that holds homologous chromosomes in close proximity and promotes the formation of genetic crossovers and accurate meiotic chromosome segregation. In recent years, numerous mutations in human SC genes have been associated with different types of male and female infertility. Here, we integrate structural information on the human SC with mouse and human genetics to describe the molecular mechanisms by which SC mutations can result in human infertility. We outline certain themes in which different SC proteins are susceptible to different types of disease mutation and how genetic variants with seemingly minor effects on SC proteins may act as dominant-negative mutations in which the heterozygous state is pathogenic.
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Affiliation(s)
- Ian R Adams
- Medical Research Council (MRC) Human Genetics Unit, MRC Institute of Genetics and Cancer, University of Edinburgh, Edinburgh, United Kingdom;
| | - Owen R Davies
- Wellcome Centre for Cell Biology, Institute of Cell Biology, University of Edinburgh, Edinburgh, United Kingdom;
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6
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Farini D, De Felici M. The Beginning of Meiosis in Mammalian Female Germ Cells: A Never-Ending Story of Intrinsic and Extrinsic Factors. Int J Mol Sci 2022; 23:ijms232012571. [PMID: 36293427 PMCID: PMC9604137 DOI: 10.3390/ijms232012571] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2022] [Revised: 10/06/2022] [Accepted: 10/18/2022] [Indexed: 11/16/2022] Open
Abstract
Meiosis is the unique division of germ cells resulting in the recombination of the maternal and paternal genomes and the production of haploid gametes. In mammals, it begins during the fetal life in females and during puberty in males. In both cases, entering meiosis requires a timely switch from the mitotic to the meiotic cell cycle and the transition from a potential pluripotent status to meiotic differentiation. Revealing the molecular mechanisms underlying these interrelated processes represents the essence in understanding the beginning of meiosis. Meiosis facilitates diversity across individuals and acts as a fundamental driver of evolution. Major differences between sexes and among species complicate the understanding of how meiosis begins. Basic meiotic research is further hindered by a current lack of meiotic cell lines. This has been recently partly overcome with the use of primordial-germ-cell-like cells (PGCLCs) generated from pluripotent stem cells. Much of what we know about this process depends on data from model organisms, namely, the mouse; in mice, the process, however, appears to differ in many aspects from that in humans. Identifying the mechanisms and molecules controlling germ cells to enter meiosis has represented and still represents a major challenge for reproductive medicine. In fact, the proper execution of meiosis is essential for fertility, for maintaining the integrity of the genome, and for ensuring the normal development of the offspring. The main clinical consequences of meiotic defects are infertility and, probably, increased susceptibility to some types of germ-cell tumors. In the present work, we report and discuss data mainly concerning the beginning of meiosis in mammalian female germ cells, referring to such process in males only when pertinent. After a brief account of this process in mice and humans and an historical chronicle of the major hypotheses and progress in this topic, the most recent results are reviewed and discussed.
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Loup B, Poumerol E, Jouneau L, Fowler PA, Cotinot C, Mandon-Pépin B. BPA disrupts meiosis I in oogonia by acting on pathways including cell cycle regulation, meiosis initiation and spindle assembly. Reprod Toxicol 2022; 111:166-177. [PMID: 35667523 DOI: 10.1016/j.reprotox.2022.06.001] [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: 01/02/2022] [Revised: 05/16/2022] [Accepted: 06/01/2022] [Indexed: 11/25/2022]
Abstract
The negative in utero effects of bisphenol A (BPA) on female reproduction are of concern since the ovarian reserve of primordial follicles is constituted during the fetal period. This time-window is difficult to access, particularly in humans. Animal models and explant culture systems are, therefore, vital tools for investigating EDC impacts on primordial germ cells (PGCs). Here, we investigated the effects of BPA on prophase I meiosis in the fetal sheep ovary. We established an in vitro model of early gametogenesis through retinoic acid (RA)-induced differentiation of sheep PGCs that progressed through meiosis. Using this system, we demonstrated that BPA (3×10-7 M & 3×10-5M) exposure for 20 days disrupted meiotic initiation and completion in sheep oogonia and induced transcriptomic modifications of exposed explants. After exposure to the lowest concentrations of BPA (3×10-7M), only 2 probes were significantly up-regulated corresponding to NR2F1 and TMEM167A transcripts. In contrast, after exposure to 3×10-5M BPA, 446 probes were deregulated, 225 were down- and 221 were up-regulated following microarray analysis. Gene Ontology (GO) annotations of differentially expressed genes revealed that pathways mainly affected were involved in cell-cycle phase transition, meiosis and spindle assembly. Differences in key gene expression within each pathway were validated by qRT-PCR. This study provides a novel model for direct examination of the molecular pathways of environmental toxicants on early female gametogenesis and novel insights into the mechanisms by which BPA affects meiosis I. BPA exposure could thereby disrupt ovarian reserve formation by inhibiting meiotic progression of oocytes I and consequently by increasing atresia of primordial follicles containing defective oocytes.
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Affiliation(s)
- Benoit Loup
- Université Paris-Saclay, UVSQ, ENVA, INRAE, BREED, 78350, Jouy-en-Josas, France.
| | - Elodie Poumerol
- Université Paris-Saclay, UVSQ, ENVA, INRAE, BREED, 78350, Jouy-en-Josas, France.
| | - Luc Jouneau
- Université Paris-Saclay, UVSQ, ENVA, INRAE, BREED, 78350, Jouy-en-Josas, France.
| | - Paul A Fowler
- Institute of Medical Sciences, School of Medicine, Medical Sciences & Nutrition, University of Aberdeen, Foresterhill, Aberdeen, AB25 2ZD, UK.
| | - Corinne Cotinot
- Université Paris-Saclay, UVSQ, ENVA, INRAE, BREED, 78350, Jouy-en-Josas, France.
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8
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Rengaraj D, Cha DG, Park KJ, Lee KY, Woo SJ, Han JY. Finer resolution analysis of transcriptional programming during the active migration of chicken primordial germ cells. Comput Struct Biotechnol J 2022; 20:5911-5924. [PMID: 36382185 PMCID: PMC9636429 DOI: 10.1016/j.csbj.2022.10.034] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2022] [Revised: 10/04/2022] [Accepted: 10/21/2022] [Indexed: 12/01/2022] Open
Abstract
Primordial germ cells (PGCs) in chickens polarize and move passively toward the anterior region by the morphogenetic movement of the embryo. Further migration of PGCs towards the genital ridge via the germinal crescent region and blood vessels occurs actively through the chemoattractive signals. The mechanisms of initiation of PGCs migration, lodging the PGCs in the vascular system, and colonization of PGCs in the gonads are well-studied. However, transcriptome sequencing-based cues directing the migration of the PGCs towards gonads, some of the relevant molecules, biological processes, and transcription factors (TFs) are less studied in chickens. The current study comprehensively interprets the transcriptional programming of PGCs during their active migration (E2.5 to E8). Current results revealed several vital understandings, including a set of genes that upregulated male-specifically (XPA, GNG10, RPL17, RPS23, and NDUFS4) or female-specifically (HINTW, NIPBL, TERAL2, ATP5F1AW, and SMAD2W) in migrating PGCs, and transcriptionally distinct PGCs, particularly in the gonadal environment. We identified DNA methylation and histone modification-associated genes that are novel in chicken PGCs and show a time-dependent enrichment in migrating PGCs. We further identified a large number of differentially expressed genes (DEGs, including TFs) in blood PGCs (at E2.5) compared to gonadal PGCs (at E8) in both sexes; however, this difference was greater in males. We also revealed the enriched biological processes and signaling pathways of significant DEGs identified commonly, male-specifically, or female-specifically between the PGCs isolated at E2.5, E6, and E8. Collectively, these analyses provide molecular insights into chicken PGCs during their active migration phase.
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Affiliation(s)
- Deivendran Rengaraj
- Department of Agricultural Biotechnology, and Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul 08826, Korea
| | - Dong Gon Cha
- Department of New Biology, DGIST, Daegu 42988, Korea
| | - Kyung Je Park
- Department of Agricultural Biotechnology, and Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul 08826, Korea
| | - Kyung Youn Lee
- Department of Agricultural Biotechnology, and Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul 08826, Korea
| | - Seung Je Woo
- Department of Agricultural Biotechnology, and Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul 08826, Korea
| | - Jae Yong Han
- Department of Agricultural Biotechnology, and Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul 08826, Korea
- Corresponding author at: Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Korea.
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9
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Bertho S, Clapp M, Banisch TU, Bandemer J, Raz E, Marlow FL. Zebrafish dazl regulates cystogenesis and germline stem cell specification during the primordial germ cell to germline stem cell transition. Development 2021; 148:dev187773. [PMID: 33722898 PMCID: PMC8077517 DOI: 10.1242/dev.187773] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2019] [Accepted: 03/04/2021] [Indexed: 01/14/2023]
Abstract
Fertility and gamete reserves are maintained by asymmetric divisions of the germline stem cells to produce new stem cells or daughters that differentiate as gametes. Before entering meiosis, differentiating germ cells (GCs) of sexual animals typically undergo cystogenesis. This evolutionarily conserved process involves synchronous and incomplete mitotic divisions of a GC daughter (cystoblast) to generate sister cells connected by intercellular bridges that facilitate the exchange of materials to support rapid expansion of the gamete progenitor population. Here, we investigated cystogenesis in zebrafish and found that early GCs are connected by ring canals, and show that Deleted in azoospermia-like (Dazl), a conserved vertebrate RNA-binding protein (Rbp), is a regulator of this process. Analysis of dazl mutants revealed the essential role of Dazl in regulating incomplete cytokinesis, germline cyst formation and germline stem cell specification before the meiotic transition. Accordingly, dazl mutant GCs form defective ring canals, and ultimately remain as individual cells that fail to differentiate as meiocytes. In addition to promoting cystoblast divisions and meiotic entry, dazl is required for germline stem cell establishment and fertility.
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Affiliation(s)
- Sylvain Bertho
- Department of Cell, Developmental and Regenerative Medicine, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place Box 1020 New York, NY 10029-6574, USA
| | - Mara Clapp
- Department of Developmental and Molecular Biology, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Torsten U. Banisch
- Institute of Cell Biology Center for Molecular Biology of Inflammation, Von-Esmarch-Str. 56, D-48149 Muenster, Germany
- New York University School of Medicine, Department of Cell Biology, New York, NY 10012, USA
| | - Jan Bandemer
- Institute of Cell Biology Center for Molecular Biology of Inflammation, Von-Esmarch-Str. 56, D-48149 Muenster, Germany
| | - Erez Raz
- Institute of Cell Biology Center for Molecular Biology of Inflammation, Von-Esmarch-Str. 56, D-48149 Muenster, Germany
| | - Florence L. Marlow
- Department of Cell, Developmental and Regenerative Medicine, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place Box 1020 New York, NY 10029-6574, USA
- Department of Developmental and Molecular Biology, Albert Einstein College of Medicine, Bronx, NY 10461, USA
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10
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Laureau R, Dyatel A, Dursuk G, Brown S, Adeoye H, Yue JX, De Chiara M, Harris A, Ünal E, Liti G, Adams IR, Berchowitz LE. Meiotic Cells Counteract Programmed Retrotransposon Activation via RNA-Binding Translational Repressor Assemblies. Dev Cell 2020; 56:22-35.e7. [PMID: 33278343 DOI: 10.1016/j.devcel.2020.11.008] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2020] [Revised: 06/25/2020] [Accepted: 11/06/2020] [Indexed: 12/14/2022]
Abstract
Retrotransposon proliferation poses a threat to germline integrity. While retrotransposons must be activated in developing germ cells in order to survive and propagate, how they are selectively activated in the context of meiosis is unclear. We demonstrate that the transcriptional activation of Ty3/Gypsy retrotransposons and host defense are controlled by master meiotic regulators. We show that budding yeast Ty3/Gypsy co-opts binding sites of the essential meiotic transcription factor Ndt80 upstream of the integration site, thereby tightly linking its transcriptional activation to meiotic progression. We also elucidate how yeast cells thwart Ty3/Gypsy proliferation by blocking translation of the retrotransposon mRNA using amyloid-like assemblies of the RNA-binding protein Rim4. In mammals, several inactive Ty3/Gypsy elements are undergoing domestication. We show that mammals utilize equivalent master meiotic regulators (Stra8, Mybl1, Dazl) to regulate Ty3/Gypsy-derived genes in developing gametes. Our findings inform how genes that are evolving from retrotransposons can build upon existing regulatory networks during domestication.
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Affiliation(s)
- Raphaelle Laureau
- Department of Genetics and Development, Hammer Health Sciences Center, Columbia University Irving Medical Center, New York, NY 10032, USA
| | - Annie Dyatel
- Department of Genetics and Development, Hammer Health Sciences Center, Columbia University Irving Medical Center, New York, NY 10032, USA
| | - Gizem Dursuk
- Department of Genetics and Development, Hammer Health Sciences Center, Columbia University Irving Medical Center, New York, NY 10032, USA
| | - Samantha Brown
- Department of Genetics and Development, Hammer Health Sciences Center, Columbia University Irving Medical Center, New York, NY 10032, USA
| | - Hannah Adeoye
- Department of Genetics and Development, Hammer Health Sciences Center, Columbia University Irving Medical Center, New York, NY 10032, USA
| | - Jia-Xing Yue
- Université Côte d'Azur, CNRS, INSERM, IRCAN, Nice 06107, France
| | | | - Anthony Harris
- Department of Molecular and Cell Biology, University of California Berkeley, Berkeley, CA 94720, USA
| | - Elçin Ünal
- Department of Molecular and Cell Biology, University of California Berkeley, Berkeley, CA 94720, USA
| | - Gianni Liti
- Université Côte d'Azur, CNRS, INSERM, IRCAN, Nice 06107, France
| | - Ian R Adams
- MRC Human Genetics Unit, MRC Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh EH4 2XU, UK
| | - Luke E Berchowitz
- Department of Genetics and Development, Hammer Health Sciences Center, Columbia University Irving Medical Center, New York, NY 10032, USA.
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11
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Abstract
Primary ovarian insufficiency (POI) is an uncommon yet devastating occurrence that results from a premature depletion of the ovarian pool of primordial follicles. Our understanding of both putative and plausible mechanisms underlying POI, previously considered to be largely "idiopathic", has been furthered over the past several years, largely due to advances in the field of genetics and through expansion of translational models for experimental research. In this review, our goal is to familiarize the multidisciplinary readers of the F1000 platform with the strides made in the field of reproductive medicine that hold both preventative and therapeutic implications for those women who are at risk for or who have POI.
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Affiliation(s)
- Victoria Wesevich
- Department of Obstetrics, Gynecology and Reproductive Sciences, Yale School of Medicine, New Haven, CT, USA
| | - Amanada N Kellen
- Division of Reproductive Endocrinology and Infertility, Department of Obstetrics, Gynecology and Reproductive Sciences, Yale School of Medicine, New Haven, CT, USA
| | - Lubna Pal
- Division of Reproductive Endocrinology and Infertility, Department of Obstetrics, Gynecology and Reproductive Sciences, Yale School of Medicine, New Haven, CT, USA
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12
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Mikedis MM, Fan Y, Nicholls PK, Endo T, Jackson EK, Cobb SA, de Rooij DG, Page DC. DAZL mediates a broad translational program regulating expansion and differentiation of spermatogonial progenitors. eLife 2020; 9:56523. [PMID: 32686646 PMCID: PMC7445011 DOI: 10.7554/elife.56523] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2020] [Accepted: 07/20/2020] [Indexed: 01/28/2023] Open
Abstract
Fertility across metazoa requires the germline-specific DAZ family of RNA-binding proteins. Here we examine whether DAZL directly regulates progenitor spermatogonia using a conditional genetic mouse model and in vivo biochemical approaches combined with chemical synchronization of spermatogenesis. We find that the absence of Dazl impairs both expansion and differentiation of the spermatogonial progenitor population. In undifferentiated spermatogonia, DAZL binds the 3' UTRs of ~2,500 protein-coding genes. Some targets are known regulators of spermatogonial proliferation and differentiation while others are broadly expressed, dosage-sensitive factors that control transcription and RNA metabolism. DAZL binds 3' UTR sites conserved across vertebrates at a UGUU(U/A) motif. By assessing ribosome occupancy in undifferentiated spermatogonia, we find that DAZL increases translation of its targets. In total, DAZL orchestrates a broad translational program that amplifies protein levels of key spermatogonial and gene regulatory factors to promote the expansion and differentiation of progenitor spermatogonia.
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Affiliation(s)
| | - Yuting Fan
- Whitehead Institute, Cambridge, United States.,Reproductive Medicine Center, Sixth Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
| | | | | | - Emily K Jackson
- Whitehead Institute, Cambridge, United States.,Department of Biology, Massachusetts Institute of Technology, Cambridge, United States
| | | | | | - David C Page
- Whitehead Institute, Cambridge, United States.,Department of Biology, Massachusetts Institute of Technology, Cambridge, United States.,Howard Hughes Medical Institute, Whitehead Institute, Cambridge, United States
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13
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Gura MA, Mikedis MM, Seymour KA, de Rooij DG, Page DC, Freiman RN. Dynamic and regulated TAF gene expression during mouse embryonic germ cell development. PLoS Genet 2020; 16:e1008515. [PMID: 31914128 PMCID: PMC7010400 DOI: 10.1371/journal.pgen.1008515] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2019] [Revised: 02/10/2020] [Accepted: 11/11/2019] [Indexed: 12/02/2022] Open
Abstract
Germ cells undergo many developmental transitions before ultimately becoming either eggs or sperm, and during embryonic development these transitions include epigenetic reprogramming, quiescence, and meiosis. To begin understanding the transcriptional regulation underlying these complex processes, we examined the spatial and temporal expression of TAF4b, a variant TFIID subunit required for fertility, during embryonic germ cell development. By analyzing published datasets and using our own experimental system to validate these expression studies, we determined that both Taf4b mRNA and protein are highly germ cell-enriched and that Taf4b mRNA levels dramatically increase from embryonic day 12.5–18.5. Surprisingly, additional mRNAs encoding other TFIID subunits are coordinately upregulated through this time course, including Taf7l and Taf9b. The expression of several of these germ cell-enriched TFIID genes is dependent upon Dazl and/or Stra8, known regulators of germ cell development and meiosis. Together, these data suggest that germ cells employ a highly specialized and dynamic form of TFIID to drive the transcriptional programs that underlie mammalian germ cell development. Assisted reproductive therapy and fertility preservation are increasingly used to improve human reproduction across the world, yet there are still many unanswered questions regarding what factors govern the development of eggs and sperm and how these factors work together. We previously identified a subunit of the general transcription factor TFIID, TAF4b, that is essential for fertility. However, many basic characteristics of how Taf4b and its associated TFIID family members contribute to the formation of healthy sperm and eggs in mice and humans remain unknown. In this study, we find that mouse Taf4b and several closely related TFIID subunits become highly abundant during mouse embryonic gonad development, specifically in the cells that ultimately become eggs and sperm. Here, we analyzed data from public repositories and isolated these developing cells to examine their gene expression patterns throughout embryonic development. Together these data suggest that the dynamic expression of Taf4b and other TFIID family members are dependent on the well-established reproductive cell regulators Dazl and Stra8. This understanding of Taf4b gene expression and regulation in mouse reproductive cell development is likely conserved during development of human cells and offers novel insights into the interconnectedness of the factors that govern the formation of healthy eggs and sperm.
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Affiliation(s)
- Megan A. Gura
- Brown University, MCB Graduate Program and Department of Molecular Biology, Cell Biology and Biochemistry, Providence, RI, United States of America
| | | | - Kimberly A. Seymour
- Brown University, MCB Graduate Program and Department of Molecular Biology, Cell Biology and Biochemistry, Providence, RI, United States of America
| | | | - David C. Page
- Whitehead Institute, Cambridge, MA, United States of America
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA, United States of America
- Howard Hughes Medical Institute, Whitehead Institute, Cambridge, MA, United States of America
| | - Richard N. Freiman
- Brown University, MCB Graduate Program and Department of Molecular Biology, Cell Biology and Biochemistry, Providence, RI, United States of America
- * E-mail:
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14
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Rosario R, Crichton JH, Stewart HL, Childs AJ, Adams IR, Anderson RA. Dazl determines primordial follicle formation through the translational regulation of Tex14. FASEB J 2019; 33:14221-14233. [PMID: 31659914 DOI: 10.1096/fj.201901247r] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Deleted in azoospermia-like (DAZL) is a germ cell RNA-binding protein that is essential for entry and progression through meiosis. The phenotype of the Dazl knockout mouse has extensive germ cell loss because of incomplete meiosis. We have created a Dazl hypomorph model using short interfering RNA knockdown in mouse fetal ovary cultures, allowing investigation of Dazl function in germ cell maturation. Dazl hypomorph ovaries had a phenotype of impaired germ cell nest breakdown with a 66% reduction in total follicle number and an increase in the proportion of primordial follicles (PMFs), with smaller oocytes within these follicles. There was no significant early germ cell loss or meiotic delay. Immunostaining of intercellular bridge component testis-expressed protein (Tex)14 showed ∼59% reduction in foci number and size, without any change in Tex14 mRNA levels. TEX14 expression was also confirmed in the human fetal ovary across gestation. Using 3'UTR-luciferase reporter assays, translational regulation of TEX14 was demonstrated to be DAZL-dependant. Dazl is therefore essential for normal intercellular bridges within germ cell nests and their timely breakdown, with a major impact on subsequent assembly of PMFs.-Rosario, R., Crichton, J. H., Stewart, H. L., Childs, A. J., Adams, I. R., Anderson, R. A. Dazl determines primordial follicle formation through the translational regulation of Tex14.
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Affiliation(s)
- Roseanne Rosario
- Medical Research Council (MRC) Centre for Reproductive Health, Queens Medical Research Institute, University of Edinburgh, Edinburgh, United Kingdom
| | - James H Crichton
- Medical Research Council (MRC) Human Genetics Unit, MRC Institute of Genetics and Molecular Medicine, Western General Hospital, Edinburgh, United Kingdom
| | - Hazel L Stewart
- Medical Research Council (MRC) Centre for Reproductive Health, Queens Medical Research Institute, University of Edinburgh, Edinburgh, United Kingdom
| | - Andrew J Childs
- Department of Surgery and Cancer, Institute of Reproductive and Developmental Biology, Faculty of Medicine, Imperial College London, London, United Kingdom
| | - Ian R Adams
- Medical Research Council (MRC) Human Genetics Unit, MRC Institute of Genetics and Molecular Medicine, Western General Hospital, Edinburgh, United Kingdom
| | - Richard A Anderson
- Medical Research Council (MRC) Centre for Reproductive Health, Queens Medical Research Institute, University of Edinburgh, Edinburgh, United Kingdom
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15
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Yu Y, Zhen Z, Qi H, Yuan X, Gao X, Zhang M. U2AF65 enhances milk synthesis and growth of bovine mammary epithelial cells by positively regulating the mTOR-SREBP-1c signalling pathway. Cell Biochem Funct 2019; 37:93-101. [PMID: 30773658 DOI: 10.1002/cbf.3378] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2018] [Revised: 01/21/2019] [Accepted: 01/21/2019] [Indexed: 12/14/2022]
Abstract
U2 snRNP auxiliary factor 65 kDa (U2AF65) is a splicing factor that promotes prespliceosome assembly. The function of U2AF65 in alternative splicing has been identified; however, the essential physiological role of U2AF65 remains poorly understood. In this study, we investigated the regulatory role of U2AF65 in milk synthesis and growth of bovine mammary epithelial cells (BMECs). Our results showed that U2AF65 localizes in the nucleus. Treatment with amino acids (Met and Leu) and hormones (prolactin and β-estradiol) upregulated the expression of U2AF65 in these cells. U2AF65 overexpression increased the synthesis of β-casein, triglycerides, and lactose; increased cell viability; and promoted proliferation of BMECs. Furthermore, our results showed that U2AF65 positively regulated mTOR phosphorylation and expression of mature mRNA of mTOR and SREBP-1c. Collectively, our findings demonstrate that U2AF65 regulates the mRNA expression of signalling molecules (mTOR and SREBP-1c) involved in milk synthesis and growth of BMECs, possibly via controlling the splicing and maturation of these mRNAs. U2 snRNP auxiliary factor 65 kDa (U2AF65) is a splicing factor that promotes prespliceosome assembly. The essential physiological role of U2AF65 remains poorly understood. In the present study, we confirmed that U2AF65 functions as a positive regulator of milk synthesis in and proliferation of bovine mammary epithelial cells via the mTOR-SREBP-1c signalling pathway. Therefore, our study uncovers the regulatory role of U2AF65 in milk synthesis and cell proliferation.
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Affiliation(s)
- Yanbo Yu
- Key Laboratory of Dairy Science of Education Ministry, Northeast Agricultural University, Harbin, China
| | - Zhen Zhen
- Key Laboratory of Dairy Science of Education Ministry, Northeast Agricultural University, Harbin, China
| | - Hao Qi
- Key Laboratory of Dairy Science of Education Ministry, Northeast Agricultural University, Harbin, China
| | - Xiaohan Yuan
- Key Laboratory of Dairy Science of Education Ministry, Northeast Agricultural University, Harbin, China
| | - Xuejun Gao
- Key Laboratory of Dairy Science of Education Ministry, Northeast Agricultural University, Harbin, China
| | - Minghui Zhang
- Key Laboratory of Dairy Science of Education Ministry, Northeast Agricultural University, Harbin, China
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16
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Abstract
It has long been accepted that the complement of follicles within the ovary is formed before birth in humans, or shortly after birth in rodents, and that no follicles are formed thereafter. This follows entry of all oogonia into meiosis in fetal life, with no remaining germ stem cells in the ovary, in contrast to the presence of spermatogonia in the testis. This has been brought back into debate in recent years, following the demonstration of isolation of cells expressing both germline and stem markers from the postnatal ovary in several species, including humans. We describe these cells as putative ovarian stem cells. Isolation of these cells is challenging, adding to the debate as to their existence, and the validity of DDX4 as the main marker used for their isolation has also to be questioned. While different groups have used varying techniques and indeed terminology to describe these cells, the body of evidence regarding their initial characterization after isolation is growing. There remain very limited data regarding their developmental potential, but the demonstration of the production of functional oocytes from induced pluripotent stem cells and the advances in ovarian follicle culture techniques provide a basis for such studies.
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Affiliation(s)
- E E Telfer
- a Institute of Cell Biology, School of Biological Sciences , University of Edinburgh , Edinburgh , UK
| | - R A Anderson
- b MRC Centre for Reproductive Health , Queen's Medical Research Institute, University of Edinburgh , Edinburgh , UK
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17
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Li H, Liang Z, Yang J, Wang D, Wang H, Zhu M, Geng B, Xu EY. DAZL is a master translational regulator of murine spermatogenesis. Natl Sci Rev 2018; 6:455-468. [PMID: 31355046 DOI: 10.1093/nsr/nwy163] [Citation(s) in RCA: 59] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Expression of DAZ-like (DAZL) is a hallmark of vertebrate germ cells, and is essential for embryonic germ cell development and differentiation, yet the gametogenic function of DAZL has not been fully characterized and most of its in vivo direct targets remain unknown. We showed that postnatal stage-specific deletion of Dazl in mouse germ cells did not affect female fertility, but caused complete male sterility with gradual loss of spermatogonial stem cells, meiotic arrest and spermatid arrest. Using the genome-wide high-throughput sequencing of RNAs isolated by cross-linking immunoprecipitation and mass spectrometry approach, we found that DAZL bound to a large number of testicular mRNA transcripts (at least 3008) at the 3'-untranslated region and interacted with translation proteins including poly(A) binding protein. In the absence of DAZL, polysome-associated target transcripts, but not their total transcripts, were significantly decreased, resulting in a drastic reduction of an array of spermatogenic proteins and thus developmental arrest. Thus, DAZL is a master translational regulator essential for spermatogenesis.
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Affiliation(s)
- Haixin Li
- State Key Laboratory of Reproductive Medicine, Nanjing Medical University, Nanjing 211166, China
| | - Zhuqing Liang
- State Key Laboratory of Reproductive Medicine, Nanjing Medical University, Nanjing 211166, China
| | - Jian Yang
- State Key Laboratory of Reproductive Medicine, Nanjing Medical University, Nanjing 211166, China
| | - Dan Wang
- State Key Laboratory of Reproductive Medicine, Nanjing Medical University, Nanjing 211166, China
| | - Hanben Wang
- State Key Laboratory of Reproductive Medicine, Nanjing Medical University, Nanjing 211166, China
| | - Mengyi Zhu
- State Key Laboratory of Reproductive Medicine, Nanjing Medical University, Nanjing 211166, China
| | - Baobao Geng
- State Key Laboratory of Reproductive Medicine, Nanjing Medical University, Nanjing 211166, China
| | - Eugene Yujun Xu
- State Key Laboratory of Reproductive Medicine, Nanjing Medical University, Nanjing 211166, China
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18
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Bothun AM, Gao Y, Takai Y, Ishihara O, Seki H, Karger B, Tilly JL, Woods DC. Quantitative Proteomic Profiling of the Human Ovary from Early to Mid-Gestation Reveals Protein Expression Dynamics of Oogenesis and Folliculogenesis. Stem Cells Dev 2018; 27:723-735. [PMID: 29631484 DOI: 10.1089/scd.2018.0002] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
The in vivo gene networks involved in coordinating human fetal ovarian development remain obscure. In this study, quantitative mass spectrometry was conducted on ovarian tissue collected at key stages during the first two trimesters of human gestational development, confirming the expression profiling data using immunofluorescence, as well as in vitro modeling with human oogonial stem cells (OSCs) and human embryonic stem cells (ESCs). A total of 3,837 proteins were identified in samples spanning developmental days 47-137. Bioinformatics clustering and Ingenuity Pathway Analysis identified DNA mismatch repair and base excision repair as major pathways upregulated during this time. In addition, MAEL and TEX11, two key meiosis-related proteins, were identified as highly expressed during the developmental window associated with fetal oogenesis. These findings were confirmed and extended using in vitro differentiation of OSCs into in vitro derived oocytes and of ESCs into primordial germ cell-like cells and oocyte-like cells, as models. In conclusion, the global protein expression profiling data generated by this study have provided novel insights into human fetal ovarian development in vivo and will serve as a valuable new resource for future studies of the signaling pathways used to orchestrate human oogenesis and folliculogenesis.
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Affiliation(s)
- Alisha M Bothun
- 1 Department of Biology, Laboratory for Aging and Infertility Research, Northeastern University , Boston, Massachusetts
| | - Yuanwei Gao
- 2 Department of Chemistry & Chemical Biology, The Barnett Institute for Chemical and Biological Analysis, Northeastern University , Boston, Massachusetts
| | - Yasushi Takai
- 3 Department of Obstetrics and Gynecology, Saitama Medical Center, Saitama Medical University , Saitama, Japan
| | - Osamu Ishihara
- 4 Department of Obstetrics and Gynecology, Saitama Medical University , Saitama, Japan
| | - Hiroyuki Seki
- 3 Department of Obstetrics and Gynecology, Saitama Medical Center, Saitama Medical University , Saitama, Japan
| | - Barry Karger
- 2 Department of Chemistry & Chemical Biology, The Barnett Institute for Chemical and Biological Analysis, Northeastern University , Boston, Massachusetts
| | - Jonathan L Tilly
- 1 Department of Biology, Laboratory for Aging and Infertility Research, Northeastern University , Boston, Massachusetts
| | - Dori C Woods
- 1 Department of Biology, Laboratory for Aging and Infertility Research, Northeastern University , Boston, Massachusetts
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19
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Rosario R, Childs AJ, Anderson RA. RNA-binding proteins in human oogenesis: Balancing differentiation and self-renewal in the female fetal germline. Stem Cell Res 2017; 21:193-201. [PMID: 28434825 PMCID: PMC5446320 DOI: 10.1016/j.scr.2017.04.008] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/07/2016] [Revised: 03/29/2017] [Accepted: 04/13/2017] [Indexed: 12/11/2022] Open
Abstract
Primordial germ cells undergo three significant processes on their path to becoming primary oocytes: the initiation of meiosis, the formation and breakdown of germ cell nests, and the assembly of single oocytes into primordial follicles. However at the onset of meiosis, the germ cell becomes transcriptionally silenced. Consequently translational control of pre-stored mRNAs plays a central role in coordinating gene expression throughout the remainder of oogenesis; RNA binding proteins are key to this regulation. In this review we examine the role of exemplars of such proteins, namely LIN28, DAZL, BOLL and FMRP, and highlight how their roles during germ cell development are critical to oogenesis and the establishment of the primordial follicle pool. RNA-binding proteins (RBPs) are key regulators of gene expression during oogenesis. RBPs LIN28, DAZL, BOLL and FMRP display stage-specific expression in fetal oocytes. LIN28 and DAZL may regulate self-renewal and progression into meiosis respectively. BOLL and FMRP may be involved in the later stages of prophase I and oocyte growth. RBPs may have critical roles in establishing the ovarian reserve during fetal life.
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Affiliation(s)
- Roseanne Rosario
- MRC Centre for Reproductive Health, Queen's Medical Research Institute, University of Edinburgh, 47 Little France Crescent, Edinburgh EH16 4TJ, UK
| | - Andrew J Childs
- Department of Comparative Biomedical Sciences, The Royal Veterinary College, London NW1 0TU, UK
| | - Richard A Anderson
- MRC Centre for Reproductive Health, Queen's Medical Research Institute, University of Edinburgh, 47 Little France Crescent, Edinburgh EH16 4TJ, UK.
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