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Du G, Oatley MJ, Law NC, Robbins C, Wu X, Oatley JM. Proper timing of a quiescence period in precursor prospermatogonia is required for stem cell pool establishment in the male germline. Development 2021; 148:261737. [PMID: 33929507 DOI: 10.1242/dev.194571] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Accepted: 03/30/2021] [Indexed: 11/20/2022]
Abstract
The stem cell-containing undifferentiated spermatogonial population in mammals, which ensures continual sperm production, arises during development from prospermatogonial precursors. Although a period of quiescence is known to occur in prospermatogonia prior to postnatal spermatogonial transition, the importance of this has not been defined. Here, using mouse models with conditional knockout of the master cell cycle regulator Rb1 to disrupt normal timing of the quiescence period, we found that failure to initiate mitotic arrest during fetal development leads to prospermatogonial apoptosis and germline ablation. Outcomes of single-cell RNA-sequencing analysis indicate that oxidative phosphorylation activity and inhibition of meiotic initiation are disrupted in prospermatogonia that fail to enter quiescence on a normal timeline. Taken together, these findings suggest that key layers of programming are laid down during the quiescent period in prospermatogonia to ensure proper fate specification and fitness in postnatal life.
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Affiliation(s)
- Guihua Du
- State Key Laboratory of Reproductive Medicine, Nanjing Medical University, Nanjing, Jiangsu, 211166, China.,School of Molecular Biosciences, Center for Reproductive Biology, College of Veterinary Medicine, Washington State University, Pullman, WA 99164, USA
| | - Melissa J Oatley
- School of Molecular Biosciences, Center for Reproductive Biology, College of Veterinary Medicine, Washington State University, Pullman, WA 99164, USA
| | - Nathan C Law
- School of Molecular Biosciences, Center for Reproductive Biology, College of Veterinary Medicine, Washington State University, Pullman, WA 99164, USA
| | - Colton Robbins
- School of Molecular Biosciences, Center for Reproductive Biology, College of Veterinary Medicine, Washington State University, Pullman, WA 99164, USA
| | - Xin Wu
- State Key Laboratory of Reproductive Medicine, Nanjing Medical University, Nanjing, Jiangsu, 211166, China
| | - Jon M Oatley
- School of Molecular Biosciences, Center for Reproductive Biology, College of Veterinary Medicine, Washington State University, Pullman, WA 99164, USA
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Sorrenti M, Klinger FG, Iona S, Rossi V, Marcozzi S, DE Felici M. Expression and possible roles of extracellular signal-related kinases 1-2 (ERK1-2) in mouse primordial germ cell development. J Reprod Dev 2020; 66:399-409. [PMID: 32418930 PMCID: PMC7593634 DOI: 10.1262/jrd.2019-141] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
In the present work, we described the expression and activity of extracellular signal-related kinases 1-2 (ERK1-2) in mouse primordial germ cells (PGCs) from
8.5–14.5 days post coitum (dpc) and investigated whether these kinases play a role in regulating the various processes of PGC development. Using
immunofluorescence and immunoblotting to detect the active phosphorylated form of ERK1-2 (p-ERK1-2), we found that the kinases were present in most
proliferating 8.5–10.5 dpc PGCs, low in 11.5 dpc PGCs, and progressively increasing between 12.5–14.5 dpc both in female and male PGCs. In
vitro culture experiments showed that inhibiting activation of ERK1-2 with the MEK-specific inhibitor U0126 significantly reduced the growth of 8.5
dpc PGCs in culture but had little effect on 11.5–12.5 dpc PGCs. Moreover, we found that the inhibitor did not affect the adhesion of 11.5 dpc PGCs, but it
significantly reduced their motility features onto a cell monolayer. Further, while the ability of female PGCs to begin meiosis was not significantly affected
by U0126, their progression through meiotic prophase I was slowed down. Notably, the activity of ERK1-2 was necessary for maintaining the correct expression of
oocyte-specific genes crucial for germ cells survival and the formation of primordial follicles.
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Affiliation(s)
- Maria Sorrenti
- Department of Biomedicine and Prevention, Section of Histology and Embryology, University of Rome "Tor Vergata", Rome 00173, Italy
| | - Francesca Gioia Klinger
- Department of Biomedicine and Prevention, Section of Histology and Embryology, University of Rome "Tor Vergata", Rome 00173, Italy
| | - Saveria Iona
- Department of Biomedicine and Prevention, Section of Histology and Embryology, University of Rome "Tor Vergata", Rome 00173, Italy
| | - Valerio Rossi
- Department of Biomedicine and Prevention, Section of Histology and Embryology, University of Rome "Tor Vergata", Rome 00173, Italy
| | - Serena Marcozzi
- Department of Biomedicine and Prevention, Section of Histology and Embryology, University of Rome "Tor Vergata", Rome 00173, Italy
| | - Massimo DE Felici
- Department of Biomedicine and Prevention, Section of Histology and Embryology, University of Rome "Tor Vergata", Rome 00173, Italy
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Wang JH, Li Y, Deng SL, Liu YX, Lian ZX, Yu K. Recent Research Advances in Mitosis during Mammalian Gametogenesis. Cells 2019; 8:cells8060567. [PMID: 31185583 PMCID: PMC6628140 DOI: 10.3390/cells8060567] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2019] [Revised: 06/02/2019] [Accepted: 06/06/2019] [Indexed: 12/13/2022] Open
Abstract
Mitosis is a highly sophisticated and well-regulated process during the development and differentiation of mammalian gametogenesis. The regulation of mitosis plays an essential role in keeping the formulation in oogenesis and gametogenesis. In the past few years, substantial research progress has been made by showing that cyclins/cyclin-dependent kinase (CDK) have roles in the regulation of meiosis. In addition, more functional signaling molecules have been discovered in mitosis. Growing evidence has also indicated that miRNAs influence cell cycling. In this review, we focus on specific genes, cyclins/Cdk, signaling pathways/molecules, and miRNAs to discuss the latest achievements in understanding their roles in mitosis during gametogenesis. Further elucidation of mitosis during gametogenesis may facilitate delineating all processes of mammalian reproduction and the development of disease treatments.
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Affiliation(s)
- Jia-Hao Wang
- Beijing Key Laboratory for Animal Genetic Improvement, National Engineering Laboratory for Animal Breeding, Key Laboratory of Animal Genetics and Breeding of the Ministry of Agriculture, College of Animal Science and Technology, China Agricultural University, Beijing 100193, China.
| | - Yan Li
- Beijing Key Laboratory for Animal Genetic Improvement, National Engineering Laboratory for Animal Breeding, Key Laboratory of Animal Genetics and Breeding of the Ministry of Agriculture, College of Animal Science and Technology, China Agricultural University, Beijing 100193, China.
| | - Shou-Long Deng
- CAS Key Laboratory of Genome Sciences and Information, Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing 100101, China.
| | - Yi-Xun Liu
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China.
| | - Zheng-Xing Lian
- Beijing Key Laboratory for Animal Genetic Improvement, National Engineering Laboratory for Animal Breeding, Key Laboratory of Animal Genetics and Breeding of the Ministry of Agriculture, College of Animal Science and Technology, China Agricultural University, Beijing 100193, China.
| | - Kun Yu
- Beijing Key Laboratory for Animal Genetic Improvement, National Engineering Laboratory for Animal Breeding, Key Laboratory of Animal Genetics and Breeding of the Ministry of Agriculture, College of Animal Science and Technology, China Agricultural University, Beijing 100193, China.
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Zaveri L, Dhawan J. Cycling to Meet Fate: Connecting Pluripotency to the Cell Cycle. Front Cell Dev Biol 2018; 6:57. [PMID: 29974052 PMCID: PMC6020794 DOI: 10.3389/fcell.2018.00057] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2018] [Accepted: 05/14/2018] [Indexed: 01/26/2023] Open
Abstract
Pluripotent stem cells are characterized by their high proliferative rates, their ability to self-renew and their potential to differentiate to all the three germ layers. This rapid proliferation is brought about by a highly modified cell cycle that allows the cells to quickly shuttle from DNA synthesis to cell division, by reducing the time spent in the intervening gap phases. Many key regulators that define the somatic cell cycle are either absent or exhibit altered behavior, allowing the pluripotent cell to bypass cell cycle checkpoints typical of somatic cells. Experimental analysis of this modified stem cell cycle has been challenging due to the strong link between rapid proliferation and pluripotency, since perturbations to the cell cycle or pluripotency factors result in differentiation. Despite these hurdles, our understanding of this unique cell cycle has greatly improved over the past decade, in part because of the availability of new technologies that permit the analysis of single cells in heterogeneous populations. This review aims to highlight some of the recent discoveries in this area with a special emphasis on different states of pluripotency. We also discuss the highly interlinked network that connects pluripotency factors and key cell cycle genes and review evidence for how this interdependency may promote the rapid cell cycle. This issue gains translational importance since disruptions in stem cell proliferation and differentiation can impact disorders at opposite ends of a spectrum, from cancer to degenerative disease.
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Affiliation(s)
- Lamuk Zaveri
- Institute for Stem Cell Biology and Regenerative Medicine, Bangalore, India.,CSIR - Centre for Cellular and Molecular Biology, Hyderabad, India.,Manipal Academy of Higher Education, Manipal, India
| | - Jyotsna Dhawan
- Institute for Stem Cell Biology and Regenerative Medicine, Bangalore, India.,CSIR - Centre for Cellular and Molecular Biology, Hyderabad, India
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Abstract
Gonocytes (or prospermatogonia) are the precursors to spermatogonial stem cells (SSCs), which provide the foundation for spermatogenesis through their ability to both self-renew and generate daughter cells. Despite their relative importance, the regulatory mechanisms that govern gonocyte maintenance and transition to SSCs are poorly understood. Recently, we reported that constitutive activation of NOTCH1 signaling in Sertoli cells causes gonocyte exit from quiescence--the first suggestion of the potential role of this signaling pathway in the testis. This Extra View will review what is known about NOTCH signaling, particularly in Sertoli cells and germ cells in the testes, by providing a background on germ cell biology and a summary of our recently published data on NOTCH1 signaling in Sertoli cells. We also describe additional data showing that aberrant proliferation and differentiation of gonocytes in response to constitutive activation of NOTCH1 signaling in Sertoli cells involves de novo expression of cell cycle proteins and a marked upregulation of the KIT receptor. These data further suggest that NOTCH signaling orchestrates a dynamic balance between maintenance and differentiation of gonocytes in the perinatal testis.
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Affiliation(s)
- Thomas Xavier Garcia
- Department of Endocrine Neoplasia and Hormonal Disorders, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
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Park BW, Shen W, Linher-Melville K, Li J. Deleted in azoospermia-like enhances in vitro derived porcine germ cell formation and meiosis. Stem Cells Dev 2012; 22:939-50. [PMID: 23259838 DOI: 10.1089/scd.2012.0323] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Evidence supporting that deleted in azoospermia-like (DAZL) plays a key role during gametogenesis and meiosis continues to emerge. Our study aimed to determine whether overexpression of DAZL using a lentiviral approach in a somatic stem cell to germ cell in vitro differentiation culture could enhance the formation of primordial germ cell-like cells (PLCs) and oocyte-like cells (OLCs). Introduction of DAZL at the beginning of induced differentiation significantly increased the formation of Fragilis-positive PLCs, which was independent of mitotic proliferation. In addition, mRNA levels of the germ cell markers Oct4, Stella, and Vasa were also higher in the DAZL-transduced group and suppressed when DAZL was knocked down using small interference RNA. At later stages of differentiation, the expression of several genes associated with meiosis, including Scp3, Dmc1, Rec8, and Stra8, was determined to be significantly higher when DAZL was overexpressed, which was abrogated by its knockdown. Exogenous introduction of DAZL also increased the protein levels of SCP3 and VASA, which again was reversed by its knockdown. Although not a common phenomenon in the in vitro differentiation system, the percentage of SCP3-positive cells displaying meiotic chromosome patterns in the DAZL-transduced group was higher than in the control, as was the overall percentage of OLCs that were generated. The introduction of factors such as DAZL into a stem cell-to-germ cell differentiation culture may provide an opportunity to better understand the key genes and their interactions during gametogenesis, also providing a means to enhance the generation of germ cells in vitro.
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Affiliation(s)
- Bong-Wook Park
- Department of Animal and Poultry Science, University of Guelph, Guelph, Ontario, Canada
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Pashai N, Hao H, All A, Gupta S, Chaerkady R, De Los Angeles A, Gearhart JD, Kerr CL. Genome-wide profiling of pluripotent cells reveals a unique molecular signature of human embryonic germ cells. PLoS One 2012; 7:e39088. [PMID: 22737227 PMCID: PMC3380858 DOI: 10.1371/journal.pone.0039088] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2012] [Accepted: 05/18/2012] [Indexed: 11/18/2022] Open
Abstract
Human embryonic germ cells (EGCs) provide a powerful model for identifying molecules involved in the pluripotent state when compared to their progenitors, primordial germ cells (PGCs), and other pluripotent stem cells. Microarray and Principal Component Analysis (PCA) reveals for the first time that human EGCs possess a transcription profile distinct from PGCs and other pluripotent stem cells. Validation with qRT-PCR confirms that human EGCs and PGCs express many pluripotency-associated genes but with quantifiable differences compared to pluripotent embryonic stem cells (ESCs), induced pluripotent stem cells (IPSCs), and embryonal carcinoma cells (ECCs). Analyses also identified a number of target genes that may be potentially associated with their unique pluripotent states. These include IPO7, MED7, RBM26, HSPD1, and KRAS which were upregulated in EGCs along with other pluripotent stem cells when compared to PGCs. Other potential target genes were also found which may contribute toward a primed ESC-like state. These genes were exclusively up-regulated in ESCs, IPSCs and ECCs including PARP1, CCNE1, CDK6, AURKA, MAD2L1, CCNG1, and CCNB1 which are involved in cell cycle regulation, cellular metabolism and DNA repair and replication. Gene classification analysis also confirmed that the distinguishing feature of EGCs compared to ESCs, ECCs, and IPSCs lies primarily in their genetic contribution to cellular metabolism, cell cycle, and cell adhesion. In contrast, several genes were found upregulated in PGCs which may help distinguish their unipotent state including HBA1, DMRT1, SPANXA1, and EHD2. Together, these findings provide the first glimpse into a unique genomic signature of human germ cells and pluripotent stem cells and provide genes potentially involved in defining different states of germ-line pluripotency.
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Affiliation(s)
- Nikta Pashai
- Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
| | - Haiping Hao
- Deep Sequencing and Microarray Core, High Throughput Biology Center, Johns Hopkins University, Baltimore, Maryland, United States of America
| | - Angelo All
- Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
- Department of Neurology, Johns Hopkins University, Baltimore, Maryland, United States of America
| | - Siddharth Gupta
- Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
| | - Raghothama Chaerkady
- Department of Biological Chemistry, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
| | - Alejandro De Los Angeles
- Stem Cell Transplantation Program, Division of Pediatric Hematology Oncology, Children’s Hospital Boston, Massachusetts, United States of America
- Department of Biological Chemistry and Molecular Pharmacology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, Massachusetts, United States of America
- Harvard Stem Cell Institute, Cambridge, Massachusetts, United States of America
| | - John D. Gearhart
- Department of Cell and Developmental Biology, Institute of Regenerative Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
- Department of Animal Biology, Institute of Regenerative Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Candace L. Kerr
- Stem Cell Program, Institute for Cell Engineering, Johns Hopkins University, Baltimore, Maryland, United States of America
- Department of Gynecology and Obstetrics, Institute for Cell Engineering, Johns Hopkins University, Baltimore, Maryland, United States of America
- * E-mail:
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Jin J, Kwon YW, Paek JS, Cho HJ, Yu J, Lee JY, Chu IS, Park IH, Park YB, Kim HS, Kim Y. Analysis of differential proteomes of induced pluripotent stem cells by protein-based reprogramming of fibroblasts. J Proteome Res 2011; 10:977-89. [PMID: 21175196 DOI: 10.1021/pr100624f] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
The recent generation of induced pluripotent stem (iPS) cells represents a novel opportunity to complement embryonic stem (ES) cell-based approaches. iPS cells can be generated by viral transduction of specific transcription factors, but there is a potential risk of tumorigenicity by random retroviral integration. We have generated novel iPS (sFB-protein-iPS) cells from murine dermal fibroblasts (FVB-sFB) that have ES cell characteristics, using ES cell-derived cell extracts instead of performing viral transduction. Notably, only cell extracts from an ES cell line (C57-mES) on the C57/BL6 background generated iPS cells in our protocol-not an ES cell line (E14-mES) on the 129 background. Hypothesizing that determining the differences in these 2 mES cell lines will provide vital insight into the reprogramming machinery, we performed proteomic and global gene expression analysis by iTRAQ and mRNA microarray, respectively. We observed that pluripotent ES cells and ES cell extract-derived iPS cells had differential proteomes and global gene expression patterns. Notably, reprogramming-competent C57-mES cells highly expressed proteins that regulate protein synthesis and metabolism, compared with reprogramming-incompetent 129-mES cells, suggesting that there is a threshold that protein synthetic machinery must exceed to initiate reprogramming.
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Affiliation(s)
- Jonghwa Jin
- Department of Biomedical Sciences, Seoul National University College of Medicine, Seoul, Korea
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Abstract
The germ cell lineage is our lifelong reservoir of reproductive stem cells and our mechanism for transmitting genes to future generations. These highly specialised cells are specified early during development and then migrate to the embryonic gonads where sex differentiation occurs. Germ cell sex differentiation is directed by the somatic gonadal environment and is characterised by two distinct cell cycle states that are maintained until after birth. In the mouse, XY germ cells in a testis cease mitotic proliferation and enter G(1)/G(0) arrest from 12.5 dpc, while XX germ cells in an ovary enter prophase I of meiosis from 13.5 dpc. This chapter discusses the factors known to control proliferation and survival of germ cells during their journey of specification to sex differentiation during development.
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Affiliation(s)
- Cassy M Spiller
- Division of Molecular Genetics and Development, Institute for Molecular Bioscience, The University of Queensland, Brisbane QLD 4072, Australia
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Abrajano JJ, Qureshi IA, Gokhan S, Zheng D, Bergman A, Mehler MF. Differential deployment of REST and CoREST promotes glial subtype specification and oligodendrocyte lineage maturation. PLoS One 2009; 4:e7665. [PMID: 19888342 PMCID: PMC2766030 DOI: 10.1371/journal.pone.0007665] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2009] [Accepted: 10/03/2009] [Indexed: 02/07/2023] Open
Abstract
Background The repressor element-1 (RE1) silencing transcription factor/neuron-restrictive silencer factor (REST/NRSF) is a master transcriptional regulator that binds to numerous genomic RE1 sites where it acts as a molecular scaffold for dynamic recruitment of modulatory and epigenetic cofactors, including corepressor for element-1-silencing transcription factor (CoREST). CoREST also acts as a hub for various cofactors that play important roles in epigenetic remodeling and transcriptional regulation. While REST can recruit CoREST to its macromolecular complex, CoREST complexes also function at genomic sites independently of REST. REST and CoREST perform a broad array of context-specific functions, which include repression of neuronal differentiation genes in neural stem cells (NSCs) and other non-neuronal cells as well as promotion of neurogenesis. Despite their involvement in multiple aspects of neuronal development, REST and CoREST are not believed to have any direct modulatory roles in glial cell maturation. Methodology/Principal Findings We challenged this view by performing the first study of REST and CoREST in NSC-mediated glial lineage specification and differentiation. Utilizing ChIP on chip (ChIP-chip) assays, we identified distinct but overlapping developmental stage-specific profiles for REST and CoREST target genes during astrocyte (AS) and oligodendrocyte (OL) lineage specification and OL lineage maturation and myelination, including many genes not previously implicated in glial cell biology or linked to REST and CoREST regulation. Amongst these factors are those implicated in macroglial (AS and OL) cell identity, maturation, and maintenance, such as members of key developmental signaling pathways and combinatorial transcription factor codes. Conclusions/Significance Our results imply that REST and CoREST modulate not only neuronal but also glial lineage elaboration. These factors may therefore mediate critical developmental processes including the coupling of neurogenesis and gliogenesis and neuronal-glial interactions that underlie synaptic and neural network plasticity and homeostasis in health and in specific neurological disease states.
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Affiliation(s)
- Joseph J Abrajano
- Institute for Brain Disorders and Neural Regeneration, Albert Einstein College of Medicine, Bronx, New York, United States of America
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Abstract
Background information. Primordial germ cells in developing male and female gonads are responsive to somatic cell cues that direct their sex-specific differentiation into functional gametes. The first divergence of the male and female pathways is a change in cell cycle state observed from 12.5 dpc (days post coitum) in mice. At this time XY and XX germ cells cease mitotic division and enter G1/G0 arrest and meiosis prophase I respectively. Aberrant cell cycle regulation at this time can lead to disrupted ovarian development, germ cell apoptosis, reduced fertility and/or the formation of germ cell tumours. Results. In order to unravel the mechanisms utilized by germ cells to achieve and maintain the correct cell cycle states, we analysed the expression of a large number of cell cycle genes in purified germ cells across the crucial time of sex differentiation. Our results revealed common signalling for both XX and XY germ cell survival involving calcium signalling. A robust mechanism for apoptosis and checkpoint control was observed in XY germ cells, characterized by p53 and Atm (ataxia telangiectasia mutated) expression. Additionally, a member of the retinoblastoma family and p21 were identified, linking these factors to XY germ cell G1/G0 arrest. Lastly, in XX germ cells we observed a down-regulation of genes involved in both G1- and G2-phases of the cell cycle consistent with their entry into meiosis. Conclusion. The present study has provided a detailed analysis of cell cycle gene expression during fetal germ cell development and identified candidate factors warranting further investigation in order to understand cases of aberrant cell cycle control in these specialized cells.
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Han JY. Germ cells and transgenesis in chickens. Comp Immunol Microbiol Infect Dis 2009; 32:61-80. [DOI: 10.1016/j.cimid.2007.11.010] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/10/2007] [Indexed: 01/15/2023]
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Embryonic stem cell-specific microRNAs regulate the G1-S transition and promote rapid proliferation. Nat Genet 2008; 40:1478-83. [PMID: 18978791 PMCID: PMC2630798 DOI: 10.1038/ng.250] [Citation(s) in RCA: 504] [Impact Index Per Article: 31.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2008] [Accepted: 08/27/2008] [Indexed: 01/04/2023]
Abstract
Dgcr8 knockout embryonic stem (ES) cells lack microprocessor activity and hence all canonical microRNAs (miRNAs). These cells proliferate slowly and accumulate in G1 phase of the cell cycle1. Here, by screening a comprehensive library of individual miRNAs in the background of the Dgcr8 knockout ES cells, we report that multiple ES cell-specific miRNAs, members of the miR-290 family, rescue the ES cell proliferation defect. Furthermore, rescued cells no longer accumulate in the G1 phase of the cell cycle. These miRNAs function by suppressing several key regulators of the G1/S transition. These results show that post-transcriptional regulation by miRNAs promotes the G1/S transition of the ES cell cycle enabling their rapid proliferation. Furthermore, our screening strategy provides an alternative and powerful approach for uncovering the role of individual miRNAs in biological processes as it overcomes the common problem of redundancy and saturation in the miRNA system.
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