1
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Raju A, Siggia ED. A geometrical model of cell fate specification in the mouse blastocyst. Development 2024; 151:dev202467. [PMID: 38563517 PMCID: PMC11112346 DOI: 10.1242/dev.202467] [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: 10/23/2023] [Accepted: 03/20/2024] [Indexed: 04/04/2024]
Abstract
The lineage decision that generates the epiblast and primitive endoderm from the inner cell mass (ICM) is a paradigm for cell fate specification. Recent mathematics has formalized Waddington's landscape metaphor and proven that lineage decisions in detailed gene network models must conform to a small list of low-dimensional stereotypic changes called bifurcations. The most plausible bifurcation for the ICM is the so-called heteroclinic flip that we define and elaborate here. Our re-analysis of recent data suggests that there is sufficient cell movement in the ICM so the FGF signal, which drives the lineage decision, can be treated as spatially uniform. We thus extend the bifurcation model for a single cell to the entire ICM by means of a self-consistently defined time-dependent FGF signal. This model is consistent with available data and we propose additional dynamic experiments to test it further. This demonstrates that simplified, quantitative and intuitively transparent descriptions are possible when attention is shifted from specific genes to lineages. The flip bifurcation is a very plausible model for any situation where the embryo needs control over the relative proportions of two fates by a morphogen feedback.
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Affiliation(s)
- Archishman Raju
- Simons Centre for the Study of Living Machines, National Centre for Biological Sciences, Tata Institute of Fundamental Research, Bangalore 560065, India
| | - Eric D. Siggia
- Center for Studies in Physics and Biology, Rockefeller University, New York, NY 10065, USA
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2
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Krawczyk K, Wilczak K, Szczepańska K, Maleszewski M, Suwińska A. Paracrine interactions through FGFR1 and FGFR2 receptors regulate the development of preimplantation mouse chimaeric embryo. Open Biol 2022; 12:220193. [PMID: 36382369 PMCID: PMC9667143 DOI: 10.1098/rsob.220193] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The preimplantation mammalian embryo has the potential to self-organize, allowing the formation of a correctly patterned embryo despite experimental perturbation. To better understand the mechanisms controlling the developmental plasticity of the early mouse embryo, we used chimaeras composed of an embryonic day (E)3.5 or E4.5 inner cell mass (ICM) and cleaving 8-cell embryo. We revealed that the restricted potential of the ICM can be compensated for by uncommitted 8-cell embryo-derived blastomeres, thus leading to the formation of a normal chimaeric blastocyst that can undergo full development. However, whether such chimaeras maintain developmental competence depends on the presence or specific orientation of the polarized primitive endoderm layer in the ICM component. We also demonstrated that downregulated FGFR1 and FGFR2 expression in 8-cell embryos disturbs intercellular interactions between both components and results in an inverse proportion of primitive endoderm and epiblast within the resulting ICM and abnormal embryo development. This finding suggests that FGF signalling is a key part of the regulatory mechanism that assigns cells to a given lineage and ensures the proper composition of the blastocyst, which is a prerequisite for its successful implantation in the uterus and for further development.
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Affiliation(s)
- Katarzyna Krawczyk
- Department of Embryology, Institute of Developmental Biology and Biomedical Sciences, Faculty of Biology, University of Warsaw, Miecznikowa 1, 02-096 Warsaw, Poland
| | - Katarzyna Wilczak
- Department of Embryology, Institute of Developmental Biology and Biomedical Sciences, Faculty of Biology, University of Warsaw, Miecznikowa 1, 02-096 Warsaw, Poland
| | - Katarzyna Szczepańska
- Department of Embryology, Institute of Developmental Biology and Biomedical Sciences, Faculty of Biology, University of Warsaw, Miecznikowa 1, 02-096 Warsaw, Poland
| | - Marek Maleszewski
- Department of Embryology, Institute of Developmental Biology and Biomedical Sciences, Faculty of Biology, University of Warsaw, Miecznikowa 1, 02-096 Warsaw, Poland
| | - Aneta Suwińska
- Department of Embryology, Institute of Developmental Biology and Biomedical Sciences, Faculty of Biology, University of Warsaw, Miecznikowa 1, 02-096 Warsaw, Poland
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3
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Dubois A, Vincenti L, Chervova A, Greenberg MVC, Vandormael-Pournin S, Bourc'his D, Cohen-Tannoudji M, Navarro P. H3K9 tri-methylation at Nanog times differentiation commitment and enables the acquisition of primitive endoderm fate. Development 2022; 149:276335. [PMID: 35976266 PMCID: PMC9482333 DOI: 10.1242/dev.201074] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2022] [Accepted: 08/04/2022] [Indexed: 11/23/2022]
Abstract
Mouse embryonic stem cells have an inherent propensity to explore gene regulatory states associated with either self-renewal or differentiation. This property depends on ERK, which downregulates pluripotency genes such as Nanog. Here, we aimed at identifying repressive histone modifications that would mark Nanog for inactivation in response to ERK activity. We found that the transcription factor ZFP57, which binds methylated DNA to nucleate heterochromatin, is recruited upstream of Nanog, within a region enriched for histone H3 lysine 9 tri-methylation (H3K9me3). Whereas before differentiation H3K9me3 at Nanog depends on ERK, in somatic cells it becomes independent of ERK. Moreover, the loss of H3K9me3 at Nanog, induced by deleting the region or by knocking out DNA methyltransferases or Zfp57, is associated with reduced heterogeneity of NANOG, delayed commitment into differentiation and impaired ability to acquire a primitive endoderm fate. Hence, a network axis centred on DNA methylation, ZFP57 and H3K9me3 links Nanog regulation to ERK activity for the timely establishment of new cell identities. We suggest that establishment of irreversible H3K9me3 at specific master regulators allows the acquisition of particular cell fates during differentiation. Summary: A regulatory axis integrating ERK, ZFP57, DNA and H3K9 methylation underlies the transition of Nanog expression from heterogeneous and dynamic to irreversibly silenced, enabling differentiation commitment and primitive endoderm specification.
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Affiliation(s)
- Agnès Dubois
- Institut Pasteur, Université Paris Cité, CNRS UMR3738, Epigenomics, Proliferation, and the Identity of Cells Unit 1 Department of Developmental and Stem Cell Biology , , F-75015 Paris , France
| | - Loris Vincenti
- Institut Pasteur, Université Paris Cité, CNRS UMR3738, Epigenomics, Proliferation, and the Identity of Cells Unit 1 Department of Developmental and Stem Cell Biology , , F-75015 Paris , France
| | - Almira Chervova
- Institut Pasteur, Université Paris Cité, CNRS UMR3738, Epigenomics, Proliferation, and the Identity of Cells Unit 1 Department of Developmental and Stem Cell Biology , , F-75015 Paris , France
| | - Maxim V. C. Greenberg
- Department of Genetics and Developmental Biology, Institut Curie, PSL Research University, INSERM, CNRS 2 , 75005 Paris , France
- Université Paris Cité, CNRS, Institut Jacques Monod 3 , F-75013 Paris , France
| | - Sandrine Vandormael-Pournin
- Institut Pasteur, Université Paris Cité, CNRS UMR3738, Epigenomics, Proliferation, and the Identity of Cells Unit 1 Department of Developmental and Stem Cell Biology , , F-75015 Paris , France
| | - Déborah Bourc'his
- Department of Genetics and Developmental Biology, Institut Curie, PSL Research University, INSERM, CNRS 2 , 75005 Paris , France
| | - Michel Cohen-Tannoudji
- Institut Pasteur, Université Paris Cité, CNRS UMR3738, Epigenomics, Proliferation, and the Identity of Cells Unit 1 Department of Developmental and Stem Cell Biology , , F-75015 Paris , France
| | - Pablo Navarro
- Institut Pasteur, Université Paris Cité, CNRS UMR3738, Epigenomics, Proliferation, and the Identity of Cells Unit 1 Department of Developmental and Stem Cell Biology , , F-75015 Paris , France
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4
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Allègre N, Chauveau S, Dennis C, Renaud Y, Meistermann D, Estrella LV, Pouchin P, Cohen-Tannoudji M, David L, Chazaud C. NANOG initiates epiblast fate through the coordination of pluripotency genes expression. Nat Commun 2022; 13:3550. [PMID: 35729116 PMCID: PMC9213552 DOI: 10.1038/s41467-022-30858-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2021] [Accepted: 05/24/2022] [Indexed: 12/20/2022] Open
Abstract
The epiblast is the source of all mammalian embryonic tissues and of pluripotent embryonic stem cells. It differentiates alongside the primitive endoderm in a “salt and pepper” pattern from inner cell mass (ICM) progenitors during the preimplantation stages through the activity of NANOG, GATA6 and the FGF pathway. When and how epiblast lineage specification is initiated is still unclear. Here, we show that the coordinated expression of pluripotency markers defines epiblast identity. Conversely, ICM progenitor cells display random cell-to-cell variability in expression of various pluripotency markers, remarkably dissimilar from the epiblast signature and independently from NANOG, GATA6 and FGF activities. Coordination of pluripotency markers expression fails in Nanog and Gata6 double KO (DKO) embryos. Collectively, our data suggest that NANOG triggers epiblast specification by ensuring the coordinated expression of pluripotency markers in a subset of cells, implying a stochastic mechanism. These features are likely conserved, as suggested by analysis of human embryos. Pluripotent epiblast cells segregate from primitive endoderm in the blastocyst inner cell mass (ICM). Here the authors show that mosaic epiblast differentiation during mouse and human preimplantation development initiates stochastically in ICM progenitors, independently of the FGF pathway, and requires NANOG activity
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Affiliation(s)
- Nicolas Allègre
- Université Clermont Auvergne, CNRS, INSERM, GReD Institute, Faculté de Médecine, F-63000, Clermont-Ferrand, France
| | - Sabine Chauveau
- Université Clermont Auvergne, CNRS, INSERM, GReD Institute, Faculté de Médecine, F-63000, Clermont-Ferrand, France
| | - Cynthia Dennis
- Université Clermont Auvergne, CNRS, INSERM, GReD Institute, Faculté de Médecine, F-63000, Clermont-Ferrand, France
| | - Yoan Renaud
- Université Clermont Auvergne, CNRS, INSERM, GReD Institute, Faculté de Médecine, F-63000, Clermont-Ferrand, France.,Byonet, 19 rue du courait, F-63200, Riom, France
| | - Dimitri Meistermann
- Université de Nantes, CHU Nantes, INSERM, CR2TI, UMR 1064, ITUN, F-44000, Nantes, France.,Université de Nantes, CNRS, LS2N, CNRS UMR 6004, F-44000, Nantes, France
| | - Lorena Valverde Estrella
- Université Clermont Auvergne, CNRS, INSERM, GReD Institute, Faculté de Médecine, F-63000, Clermont-Ferrand, France
| | - Pierre Pouchin
- Université Clermont Auvergne, CNRS, INSERM, GReD Institute, Faculté de Médecine, F-63000, Clermont-Ferrand, France
| | - Michel Cohen-Tannoudji
- Institut Pasteur, Université Paris Cité, CNRS UMR3738, Epigenomics, Proliferation, and the Identity of Cells, Department of Developmental and Stem Cell Biology, F-75015, Paris, France
| | - Laurent David
- Université de Nantes, CHU Nantes, INSERM, CR2TI, UMR 1064, ITUN, F-44000, Nantes, France.,Université de Nantes, CHU Nantes, INSERM, CNRS, UMS Biocore, INSERM UMS 016, CNRS UMS 3556, F-44000, Nantes, France
| | - Claire Chazaud
- Université Clermont Auvergne, CNRS, INSERM, GReD Institute, Faculté de Médecine, F-63000, Clermont-Ferrand, France.
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5
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Filimonow K, de la Fuente R. Specification and role of extraembryonic endoderm lineages in the periimplantation mouse embryo. Theriogenology 2021; 180:189-206. [PMID: 34998083 DOI: 10.1016/j.theriogenology.2021.12.021] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2021] [Revised: 12/13/2021] [Accepted: 12/16/2021] [Indexed: 12/12/2022]
Abstract
During mammalian embryo development, the correct formation of the first extraembryonic endoderm lineages is fundamental for successful development. In the periimplantation blastocyst, the primitive endoderm (PrE) is formed, which gives rise to the parietal endoderm (PE) and visceral endoderm (VE) during further developmental stages. These PrE-derived lineages show significant differences in both their formation and roles. Whereas differentiation of the PE as a migratory lineage has been suggested to represent the first epithelial-to-mesenchymal transition (EMT) in development, organisation of the epithelial VE is of utmost importance for the correct axis definition and patterning of the embryo. Despite sharing a common origin, the striking differences between the VE and PE are indicative of their distinct roles in early development. However, there is a significant disparity in the current knowledge of each lineage, which reflects the need for a deeper understanding of their respective specification processes. In this review, we will discuss the origin and maturation of the PrE, PE, and VE during the periimplantation period using the mouse model as an example. Additionally, we consider the latest findings regarding the role of the PrE-derived lineages and early embryo morphogenesis, as obtained from the most recent in vitro models.
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Affiliation(s)
- Katarzyna Filimonow
- Department of Experimental Embryology, Institute of Genetics and Animal Biotechnology of the Polish Academy of Sciences, Jastrzębiec, Poland.
| | - Roberto de la Fuente
- Department of Experimental Embryology, Institute of Genetics and Animal Biotechnology of the Polish Academy of Sciences, Jastrzębiec, Poland.
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6
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Krawczyk K, Kosyl E, Częścik-Łysyszyn K, Wyszomirski T, Maleszewski M. Developmental capacity is unevenly distributed among single blastomeres of 2-cell and 4-cell stage mouse embryos. Sci Rep 2021; 11:21422. [PMID: 34728646 PMCID: PMC8563712 DOI: 10.1038/s41598-021-00834-1] [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: 06/16/2021] [Accepted: 10/14/2021] [Indexed: 11/25/2022] Open
Abstract
During preimplantation development, mammalian embryo cells (blastomeres) cleave, gradually losing their potencies and differentiating into three primary cell lineages: epiblast (EPI), trophectoderm (TE), and primitive endoderm (PE). The exact moment at which cells begin to vary in their potency for multilineage differentiation still remains unknown. We sought to answer the question of whether single cells isolated from 2- and 4-cell embryos differ in their ability to generate the progenitors and cells of blastocyst lineages. We revealed that twins were often able to develop into blastocysts containing inner cell masses (ICMs) with PE and EPI cells. Despite their capacity to create a blastocyst, the twins differed in their ability to produce EPI, PE, and TE cell lineages. In contrast, quadruplets rarely formed normal blastocysts, but instead developed into blastocysts with ICMs composed of only one cell lineage or completely devoid of an ICM altogether. We also showed that quadruplets have unequal capacities to differentiate into TE, PE, and EPI lineages. These findings could explain the difficulty of creating monozygotic twins and quadruplets from 2- and 4-cell stage mouse embryos.
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Affiliation(s)
- Katarzyna Krawczyk
- Department of Embryology, Institute of Developmental Biology and Biomedical Sciences, Faculty of Biology, University of Warsaw, Miecznikowa 1, 02-096, Warsaw, Poland.
| | - Ewa Kosyl
- Department of Embryology, Institute of Developmental Biology and Biomedical Sciences, Faculty of Biology, University of Warsaw, Miecznikowa 1, 02-096, Warsaw, Poland
| | - Karolina Częścik-Łysyszyn
- Department of Embryology, Institute of Developmental Biology and Biomedical Sciences, Faculty of Biology, University of Warsaw, Miecznikowa 1, 02-096, Warsaw, Poland
| | - Tomasz Wyszomirski
- Department of Ecology and Environmental Protection, Institute of Environmental Biology, Faculty of Biology, University of Warsaw, Żwirki i Wigury 101, 02-089, Warsaw, Poland
| | - Marek Maleszewski
- Department of Embryology, Institute of Developmental Biology and Biomedical Sciences, Faculty of Biology, University of Warsaw, Miecznikowa 1, 02-096, Warsaw, Poland.
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7
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Bora P, Gahurova L, Hauserova A, Stiborova M, Collier R, Potěšil D, Zdráhal Z, Bruce AW. DDX21 is a p38-MAPK-sensitive nucleolar protein necessary for mouse preimplantation embryo development and cell-fate specification. Open Biol 2021; 11:210092. [PMID: 34255976 PMCID: PMC8277471 DOI: 10.1098/rsob.210092] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Successful navigation of the mouse preimplantation stages of development, during which three distinct blastocyst lineages are derived, represents a prerequisite for continued development. We previously identified a role for p38-mitogen-activated kinases (p38-MAPK) regulating blastocyst inner cell mass (ICM) cell fate, specifically primitive endoderm (PrE) differentiation, that is intimately linked to rRNA precursor processing, polysome formation and protein translation regulation. Here, we develop this work by assaying the role of DEAD-box RNA helicase 21 (DDX21), a known regulator of rRNA processing, in the context of p38-MAPK regulation of preimplantation mouse embryo development. We show nuclear DDX21 protein is robustly expressed from the 16-cell stage, becoming exclusively nucleolar during blastocyst maturation, a localization dependent on active p38-MAPK. siRNA-mediated clonal Ddx21 knockdown within developing embryos is associated with profound cell-autonomous and non-autonomous proliferation defects and reduced blastocyst volume, by the equivalent peri-implantation blastocyst stage. Moreover, ICM residing Ddx21 knockdown clones express the EPI marker NANOG but rarely express the PrE differentiation marker GATA4. These data contribute further significance to the emerging importance of lineage-specific translation regulation, as identified for p38-MAPK, during mouse preimplantation development.
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Affiliation(s)
- Pablo Bora
- Laboratory of Early Mammalian Developmental Biology (LEMDB), Department of Molecular Biology and Genetics, Faculty of Science, University of South Bohemia, Branišovská 31, 37005 České Budějovice, Czech Republic
| | - Lenka Gahurova
- Laboratory of Early Mammalian Developmental Biology (LEMDB), Department of Molecular Biology and Genetics, Faculty of Science, University of South Bohemia, Branišovská 31, 37005 České Budějovice, Czech Republic.,Laboratory of Biochemistry and Molecular Biology of Germ Cells, Institute of Animal Physiology and Genetics, CAS, Rumburská 89, 27721 Liběchov, Czech Republic
| | - Andrea Hauserova
- Laboratory of Early Mammalian Developmental Biology (LEMDB), Department of Molecular Biology and Genetics, Faculty of Science, University of South Bohemia, Branišovská 31, 37005 České Budějovice, Czech Republic
| | - Martina Stiborova
- Laboratory of Early Mammalian Developmental Biology (LEMDB), Department of Molecular Biology and Genetics, Faculty of Science, University of South Bohemia, Branišovská 31, 37005 České Budějovice, Czech Republic
| | - Rebecca Collier
- Laboratory of Early Mammalian Developmental Biology (LEMDB), Department of Molecular Biology and Genetics, Faculty of Science, University of South Bohemia, Branišovská 31, 37005 České Budějovice, Czech Republic
| | - David Potěšil
- Central European Institute of Technology, Masaryk University, 62500 Brno, Czech Republic
| | - Zbyněk Zdráhal
- Central European Institute of Technology, Masaryk University, 62500 Brno, Czech Republic
| | - Alexander W Bruce
- Laboratory of Early Mammalian Developmental Biology (LEMDB), Department of Molecular Biology and Genetics, Faculty of Science, University of South Bohemia, Branišovská 31, 37005 České Budějovice, Czech Republic
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8
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p38-MAPK-mediated translation regulation during early blastocyst development is required for primitive endoderm differentiation in mice. Commun Biol 2021; 4:788. [PMID: 34172827 PMCID: PMC8233355 DOI: 10.1038/s42003-021-02290-z] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2020] [Accepted: 06/02/2021] [Indexed: 02/07/2023] Open
Abstract
Successful specification of the two mouse blastocyst inner cell mass (ICM) lineages (the primitive endoderm (PrE) and epiblast) is a prerequisite for continued development and requires active fibroblast growth factor 4 (FGF4) signaling. Previously, we identified a role for p38 mitogen-activated protein kinases (p38-MAPKs) during PrE differentiation, but the underlying mechanisms have remained unresolved. Here, we report an early blastocyst window of p38-MAPK activity that is required to regulate ribosome-related gene expression, rRNA precursor processing, polysome formation and protein translation. We show that p38-MAPK inhibition-induced PrE phenotypes can be partially rescued by activating the translational regulator mTOR. However, similar PrE phenotypes associated with extracellular signal-regulated kinase (ERK) pathway inhibition targeting active FGF4 signaling are not affected by mTOR activation. These data indicate a specific role for p38-MAPKs in providing a permissive translational environment during mouse blastocyst PrE differentiation that is distinct from classically reported FGF4-based mechanisms.
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9
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Ávila-González D, Portillo W, García-López G, Molina-Hernández A, Díaz-Martínez NE, Díaz NF. Unraveling the Spatiotemporal Human Pluripotency in Embryonic Development. Front Cell Dev Biol 2021; 9:676998. [PMID: 34249929 PMCID: PMC8262797 DOI: 10.3389/fcell.2021.676998] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2021] [Accepted: 05/21/2021] [Indexed: 11/13/2022] Open
Abstract
There have been significant advances in understanding human embryogenesis using human pluripotent stem cells (hPSCs) in conventional monolayer and 3D self-organized cultures. Thus, in vitro models have contributed to elucidate the molecular mechanisms for specification and differentiation during development. However, the molecular and functional spectrum of human pluripotency (i.e., intermediate states, pluripotency subtypes and regionalization) is still not fully understood. This review describes the mechanisms that establish and maintain pluripotency in human embryos and their differences with mouse embryos. Further, it describes a new pluripotent state representing a transition between naïve and primed pluripotency. This review also presents the data that divide pluripotency into substates expressing epiblast regionalization and amnion specification as well as primordial germ cells in primates. Finally, this work analyzes the amnion's relevance as an "signaling center" for regionalization before the onset of gastrulation.
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Affiliation(s)
- Daniela Ávila-González
- Instituto de Neurobiología, Universidad Nacional Autónoma de México, Juriquilla, Mexico
- Instituto Nacional de Perinatología, Mexico City, Mexico
| | - Wendy Portillo
- Instituto de Neurobiología, Universidad Nacional Autónoma de México, Juriquilla, Mexico
| | | | | | - Néstor E. Díaz-Martínez
- Biotecnología Médica y Farmacéutica, Centro de Investigación y Asistencia en Tecnología y Diseño del Estado de Jalisco, Guadalajara, Mexico
| | - Néstor F. Díaz
- Instituto Nacional de Perinatología, Mexico City, Mexico
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10
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A multiscale model via single-cell transcriptomics reveals robust patterning mechanisms during early mammalian embryo development. PLoS Comput Biol 2021; 17:e1008571. [PMID: 33684098 PMCID: PMC7971879 DOI: 10.1371/journal.pcbi.1008571] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Revised: 03/18/2021] [Accepted: 11/27/2020] [Indexed: 01/18/2023] Open
Abstract
During early mammalian embryo development, a small number of cells make robust fate decisions at particular spatial locations in a tight time window to form inner cell mass (ICM), and later epiblast (Epi) and primitive endoderm (PE). While recent single-cell transcriptomics data allows scrutinization of heterogeneity of individual cells, consistent spatial and temporal mechanisms the early embryo utilize to robustly form the Epi/PE layers from ICM remain elusive. Here we build a multiscale three-dimensional model for mammalian embryo to recapitulate the observed patterning process from zygote to late blastocyst. By integrating the spatiotemporal information reconstructed from multiple single-cell transcriptomic datasets, the data-informed modeling analysis suggests two major processes critical to the formation of Epi/PE layers: a selective cell-cell adhesion mechanism (via EphA4/EphrinB2) for fate-location coordination and a temporal attenuation mechanism of cell signaling (via Fgf). Spatial imaging data and distinct subsets of single-cell gene expression data are then used to validate the predictions. Together, our study provides a multiscale framework that incorporates single-cell gene expression datasets to analyze gene regulations, cell-cell communications, and physical interactions among cells in complex geometries at single-cell resolution, with direct application to late-stage development of embryogenesis.
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11
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Pokrass MJ, Ryan KA, Xin T, Pielstick B, Timp W, Greco V, Regot S. Cell-Cycle-Dependent ERK Signaling Dynamics Direct Fate Specification in the Mammalian Preimplantation Embryo. Dev Cell 2020; 55:328-340.e5. [PMID: 33091369 PMCID: PMC7658051 DOI: 10.1016/j.devcel.2020.09.013] [Citation(s) in RCA: 48] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Revised: 06/12/2020] [Accepted: 09/09/2020] [Indexed: 12/18/2022]
Abstract
Despite the noisy nature of single cells, multicellular organisms robustly generate different cell types from one zygote. This process involves dynamic cross regulation between signaling and gene expression that is difficult to capture with fixed-cell approaches. To study signaling dynamics and fate specification during preimplantation development, we generated a transgenic mouse expressing the ERK kinase translocation reporter and measured ERK activity in single cells of live embryos. Our results show primarily active ERK in both the inner cell mass and trophectoderm cells due to fibroblast growth factor (FGF) signaling. Strikingly, a subset of mitotic events results in a short pulse of ERK inactivity in both daughter cells that correlates with elevated endpoint NANOG levels. Moreover, endogenous tagging of Nanog in embryonic stem cells reveals that ERK inhibition promotes enhanced stabilization of NANOG protein after mitosis. Our data show that cell cycle, signaling, and differentiation are coordinated during preimplantation development.
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Affiliation(s)
- Michael J Pokrass
- Department Molecular Biology and Genetics, the Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Department Oncology, the Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Biochemistry, Cellular, and Molecular Biology Graduate Program, Baltimore, MD, USA
| | - Kathleen A Ryan
- Department Molecular Biology and Genetics, the Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Department Oncology, the Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Tianchi Xin
- Genetics Department, Yale School of Medicine, New Haven, CT 06520, USA
| | - Brittany Pielstick
- Biochemistry, Cellular, and Molecular Biology Graduate Program, Baltimore, MD, USA; Biomedical Engineering Department, the Johns Hopkins University, Baltimore, MD 21218, USA
| | - Winston Timp
- Biomedical Engineering Department, the Johns Hopkins University, Baltimore, MD 21218, USA
| | - Valentina Greco
- Genetics Department, Yale School of Medicine, New Haven, CT 06520, USA
| | - Sergi Regot
- Department Molecular Biology and Genetics, the Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Department Oncology, the Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.
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12
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Simon CS, Rahman S, Raina D, Schröter C, Hadjantonakis AK. Live Visualization of ERK Activity in the Mouse Blastocyst Reveals Lineage-Specific Signaling Dynamics. Dev Cell 2020; 55:341-353.e5. [PMID: 33091370 PMCID: PMC7658048 DOI: 10.1016/j.devcel.2020.09.030] [Citation(s) in RCA: 48] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2020] [Revised: 06/05/2020] [Accepted: 09/28/2020] [Indexed: 01/16/2023]
Abstract
FGF/ERK signaling is crucial for the patterning and proliferation of cell lineages that comprise the mouse blastocyst. However, ERK signaling dynamics have never been directly visualized in live embryos. To address whether differential signaling is associated with particular cell fates and states, we generated a targeted mouse line expressing an ERK-kinase translocation reporter (KTR) that enables live quantification of ERK activity at single-cell resolution. 3D time-lapse imaging of this biosensor in embryos revealed spatially graded ERK activity in the trophectoderm prior to overt polar versus mural differentiation. Within the inner cell mass (ICM), all cells relayed FGF/ERK signals with varying durations and magnitude. Primitive endoderm cells displayed higher overall levels of ERK activity, while pluripotent epiblast cells exhibited lower basal activity with sporadic pulses. These results constitute a direct visualization of signaling events during mammalian pre-implantation development and reveal the existence of spatial and temporal lineage-specific dynamics.
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Affiliation(s)
- Claire S Simon
- Developmental Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
| | - Shahadat Rahman
- Developmental Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
| | - Dhruv Raina
- Department of Systemic Cell Biology, Max Planck Institute of Molecular Physiology, Otto-Hahn-Strasse 11, 44227 Dortmund, Germany
| | - Christian Schröter
- Department of Systemic Cell Biology, Max Planck Institute of Molecular Physiology, Otto-Hahn-Strasse 11, 44227 Dortmund, Germany
| | - Anna-Katerina Hadjantonakis
- Developmental Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA.
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13
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Saiz N, Hadjantonakis AK. Coordination between patterning and morphogenesis ensures robustness during mouse development. Philos Trans R Soc Lond B Biol Sci 2020; 375:20190562. [PMID: 32829684 PMCID: PMC7482220 DOI: 10.1098/rstb.2019.0562] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/01/2020] [Indexed: 12/11/2022] Open
Abstract
The mammalian preimplantation embryo is a highly tractable, self-organizing developmental system in which three cell types are consistently specified without the need for maternal factors or external signals. Studies in the mouse over the past decades have greatly improved our understanding of the cues that trigger symmetry breaking in the embryo, the transcription factors that control lineage specification and commitment, and the mechanical forces that drive morphogenesis and inform cell fate decisions. These studies have also uncovered how these multiple inputs are integrated to allocate the right number of cells to each lineage despite inherent biological noise, and as a response to perturbations. In this review, we summarize our current understanding of how these processes are coordinated to ensure a robust and precise developmental outcome during early mouse development. This article is part of a discussion meeting issue 'Contemporary morphogenesis'.
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Affiliation(s)
- Néstor Saiz
- Developmental Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, NY 10065, USA
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14
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Bessonnard S, Vandormael-Pournin S, Coqueran S, Cohen-Tannoudji M, Artus J. PDGF Signaling in Primitive Endoderm Cell Survival Is Mediated by PI3K-mTOR Through p53-Independent Mechanism. Stem Cells 2019; 37:888-898. [PMID: 30913328 DOI: 10.1002/stem.3008] [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: 10/12/2018] [Revised: 02/18/2019] [Accepted: 03/12/2019] [Indexed: 12/22/2022]
Abstract
Receptor tyrosine kinase signaling pathways are key regulators for the formation of the primitive endoderm (PrE) and the epiblast (Epi) from the inner cell mass (ICM) of the mouse preimplantation embryo. Among them, FGF signaling is critical for PrE cell specification, whereas PDGF signaling is critical for the survival of committed PrE cells. Here, we investigated possible functional redundancies among FGF, PDGF, and KIT signaling and showed that only PDGF signaling is involved in PrE cell survival. In addition, we analyzed the effectors downstream of PDGFRα. Our results suggest that the role of PDGF signaling in PrE cell survival is mediated through PI3K-mTOR and independently from p53. Lastly, we uncovered a role for PI3K-mTOR signaling in the survival of Epi cells. Taken together, we propose that survival of ICM cell lineages relies on the regulation of PI3K-mTOR signaling through the regulation of multiple signaling pathways. Stem Cells 2019;37:888-898.
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Affiliation(s)
- Sylvain Bessonnard
- Early Mammalian Development and Stem Cell Biology, Institut Pasteur, CNRS UMR 3738, Paris, France
| | | | - Sabrina Coqueran
- Early Mammalian Development and Stem Cell Biology, Institut Pasteur, CNRS UMR 3738, Paris, France
| | - Michel Cohen-Tannoudji
- Early Mammalian Development and Stem Cell Biology, Institut Pasteur, CNRS UMR 3738, Paris, France
| | - Jérôme Artus
- Early Mammalian Development and Stem Cell Biology, Institut Pasteur, CNRS UMR 3738, Paris, France
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15
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Azami T, Bassalert C, Allègre N, Estrella LV, Pouchin P, Ema M, Chazaud C. Regulation of ERK signalling pathway in the developing mouse blastocyst. Development 2019; 146:dev.177139. [DOI: 10.1242/dev.177139] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2019] [Accepted: 07/11/2019] [Indexed: 12/24/2022]
Abstract
Activation of the ERK signalling pathway is essential for the differentiation of the inner cell mass (ICM) during mouse preimplantation development. We show here that ERK phosphorylation is present in ICM precursor cells, in differentiated Primitive Endoderm (PrE) cells as well as in the mature, formative state Epiblast (Epi). We further show that DUSP4 and ETV5, factors often involved in negative feedback loops of the FGF pathway are differently regulated. While DUSP4 presence clearly depends on ERK phosphorylation in PrE cells, ETV5 localises mainly to Epi cells. Unexpectedly, ETV5 accumulation does not depend on direct activation by ERK but requires NANOG activity. Indeed ETV5, like Fgf4 expression, is not present in Nanog mutant embryos. Our results lead us to propose that in pluripotent early Epi cells, NANOG induces the expression of both Fgf4 and Etv5 to enable the differentiation of neighbouring cells into PrE while protecting the Epi identity from autocrine signalling.
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Affiliation(s)
- Takuya Azami
- Department of Stem Cells and Human Disease Models, Research Center for Animal Life Science, Shiga University of Medical Science, Seta, Tsukinowa-cho, Otsu, Shiga 520-2192, Japan
| | - Cécilia Bassalert
- GReD laboratory, Université Clermont Auvergne, CNRS, Inserm, Faculté de Médecine, CRBC, F-63000 Clermont-Ferrand, France
| | - Nicolas Allègre
- GReD laboratory, Université Clermont Auvergne, CNRS, Inserm, Faculté de Médecine, CRBC, F-63000 Clermont-Ferrand, France
| | - Lorena Valverde Estrella
- GReD laboratory, Université Clermont Auvergne, CNRS, Inserm, Faculté de Médecine, CRBC, F-63000 Clermont-Ferrand, France
| | - Pierre Pouchin
- GReD laboratory, Université Clermont Auvergne, CNRS, Inserm, Faculté de Médecine, CRBC, F-63000 Clermont-Ferrand, France
| | - Masatsugu Ema
- Department of Stem Cells and Human Disease Models, Research Center for Animal Life Science, Shiga University of Medical Science, Seta, Tsukinowa-cho, Otsu, Shiga 520-2192, Japan
- Institute for the Advanced Study of Human Biology (ASHBi), Kyoto University Institute for Advanced Study 606-8501, Japan
| | - Claire Chazaud
- GReD laboratory, Université Clermont Auvergne, CNRS, Inserm, Faculté de Médecine, CRBC, F-63000 Clermont-Ferrand, France
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16
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Mathew B, Muñoz-Descalzo S, Corujo-Simon E, Schröter C, Stelzer EHK, Fischer SC. Mouse ICM Organoids Reveal Three-Dimensional Cell Fate Clustering. Biophys J 2018; 116:127-141. [PMID: 30514631 PMCID: PMC6341222 DOI: 10.1016/j.bpj.2018.11.011] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2018] [Revised: 10/26/2018] [Accepted: 11/09/2018] [Indexed: 02/05/2023] Open
Abstract
During mammalian preimplantation, cells of the inner cell mass (ICM) adopt either an embryonic or an extraembryonic fate. This process is tightly regulated in space and time and has been studied previously in mouse embryos and embryonic stem cell models. Current research suggests that cell fates are arranged in a salt-and-pepper pattern of random cell positioning or a spatially alternating pattern. However, the details of the three-dimensional patterns of cell fate specification have not been investigated in the embryo nor in in vitro systems. We developed ICM organoids as a, to our knowledge, novel three-dimensional in vitro stem cell system to model mechanisms of fate decisions that occur in the ICM. ICM organoids show similarities to the in vivo system that arise regardless of the differences in geometry and total cell number. Inspecting ICM organoids and mouse embryos, we describe a so far unknown local clustering of cells with identical fates in both systems. These findings are based on the three-dimensional quantitative analysis of spatiotemporal patterns of NANOG and GATA6 expression in combination with computational rule-based modeling. The pattern identified by our analysis is distinct from the current view of a salt-and-pepper pattern. Our investigation of the spatial distributions both in vivo and in vitro dissects the contributions of the different parts of the embryo to cell fate specifications. In perspective, our combination of quantitative in vivo and in vitro analyses can be extended to other mammalian organisms and thus creates a powerful approach to study embryogenesis.
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Affiliation(s)
- Biena Mathew
- Physikalische Biologie, Fachbereich Biowissenschaften, Buchmann Institute for Molecular Life Sciences, Goethe-Universität Frankfurt am Main, Frankfurt am Main, Germany
| | - Silvia Muñoz-Descalzo
- Department of Biology and Biochemistry, University of Bath, Bath, United Kingdom; Instituto Universitario de Investigaciones Biomédicas y Sanitarias, Universidad Las Palmas de Gran Canaria, Las Palmas de Gran Canaria, Spain
| | - Elena Corujo-Simon
- Instituto Universitario de Investigaciones Biomédicas y Sanitarias, Universidad Las Palmas de Gran Canaria, Las Palmas de Gran Canaria, Spain
| | - Christian Schröter
- Department of Systemic Cell Biology, Max-Planck-Institute of Molecular Physiology, Dortmund, Germany
| | - Ernst H K Stelzer
- Physikalische Biologie, Fachbereich Biowissenschaften, Buchmann Institute for Molecular Life Sciences, Goethe-Universität Frankfurt am Main, Frankfurt am Main, Germany
| | - Sabine C Fischer
- Physikalische Biologie, Fachbereich Biowissenschaften, Buchmann Institute for Molecular Life Sciences, Goethe-Universität Frankfurt am Main, Frankfurt am Main, Germany.
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17
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Plusa B, Hadjantonakis AK. (De)constructing the blastocyst: Lessons in self-organization from the mouse. ACTA ACUST UNITED AC 2018. [DOI: 10.1016/j.coisb.2018.08.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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18
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Konishi R, Nakano T, Yamaguchi S. Distinct requirements for the maintenance and establishment of mouse embryonic stem cells. Stem Cell Res 2018; 31:55-61. [PMID: 30015174 DOI: 10.1016/j.scr.2018.07.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/12/2018] [Revised: 06/19/2018] [Accepted: 07/09/2018] [Indexed: 10/28/2022] Open
Abstract
Mouse embryonic stem cells (ESCs) that maintain a sustainable pluripotent state are derived from the inner cell mass (ICM) of blastocysts, in which pluripotency is lost during differentiation in vivo. It is unclear when and how the ability to maintain pluripotency is acquired during the derivation of ESCs. We analyzed the required culture condition for the maintenance and establishment of ESCs in detail. Even at low concentration of the GSK3β inhibitor and LIF (LowGiL), the expression levels of pluripotency markers and the chimera-producing ability of the cells were comparable with those of ESCs cultured in the presence of both inhibitors and LIF (2iL). However, blastocysts underwent spontaneous differentiation, and ESCs were not established under LowGiL condition. Time-course analysis showed that 2iL condition for three days from the initiation of culture was sufficient for the acquisition of permanent pluripotency. Although X chromosome-linked pluripotent genes were significantly up-regulated during the culture of both male and female blastocysts in 2iL condition, no such up-regulation was observed in LowGiL condition. In conclusion, 2iL-dependent activation of these X-linked genes at the earliest phase of ESC derivation is one of the molecular bases for the acquisition of permanent pluripotency.
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Affiliation(s)
- Riyo Konishi
- Department of Stem Cell Pathology, Graduate School of Frontier Biosciences, Osaka University, Yamada-oka 2-2 Suita, Osaka 565-0871, Japan
| | - Toru Nakano
- Department of Stem Cell Pathology, Graduate School of Frontier Biosciences, Osaka University, Yamada-oka 2-2 Suita, Osaka 565-0871, Japan; Department of Pathology, Medical School, Osaka University, Yamada-oka 2-2 Suita, Osaka 565-0871, Japan; CREST, Japan Agency for Medical Research and Development (AMED), Japan
| | - Shinpei Yamaguchi
- Department of Pathology, Medical School, Osaka University, Yamada-oka 2-2 Suita, Osaka 565-0871, Japan; PRESTO, Japan Science and Technology Agency (JST), Japan.
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19
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White MD, Zenker J, Bissiere S, Plachta N. Instructions for Assembling the Early Mammalian Embryo. Dev Cell 2018; 45:667-679. [DOI: 10.1016/j.devcel.2018.05.013] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2017] [Revised: 01/23/2018] [Accepted: 05/10/2018] [Indexed: 12/15/2022]
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20
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The Pleiotropic Effects of the Canonical Wnt Pathway in Early Development and Pluripotency. Genes (Basel) 2018; 9:genes9020093. [PMID: 29443926 PMCID: PMC5852589 DOI: 10.3390/genes9020093] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2017] [Revised: 01/30/2018] [Accepted: 01/30/2018] [Indexed: 12/20/2022] Open
Abstract
The technology to derive embryonic and induced pluripotent stem cells from early embryonic stages and adult somatic cells, respectively, emerged as a powerful resource to enable the establishment of new in vitro models, which recapitulate early developmental processes and disease. Additionally, pluripotent stem cells (PSCs) represent an invaluable source of relevant differentiated cell types with immense potential for regenerative medicine and cell replacement therapies. Pluripotent stem cells support self-renewal, potency and proliferation for extensive periods of culture in vitro. However, the core pathways that rule each of these cellular features specific to PSCs only recently began to be clarified. The Wnt signaling pathway is pivotal during early embryogenesis and is central for the induction and maintenance of the pluripotency of PSCs. Signaling by the Wnt family of ligands is conveyed intracellularly by the stabilization of β-catenin in the cytoplasm and in the nucleus, where it elicits the transcriptional activity of T-cell factor (TCF)/lymphoid enhancer factor (LEF) family of transcription factors. Interestingly, in PSCs, the Wnt/β-catenin–TCF/LEF axis has several unrelated and sometimes opposite cellular functions such as self-renewal, stemness, lineage commitment and cell cycle regulation. In addition, tight control of the Wnt signaling pathway enhances reprogramming of somatic cells to induced pluripotency. Several recent research efforts emphasize the pleiotropic functions of the Wnt signaling pathway in the pluripotent state. Nonetheless, conflicting results and unanswered questions still linger. In this review, we will focus on the diverse functions of the canonical Wnt signaling pathway on the developmental processes preceding embryo implantation, as well as on its roles in pluripotent stem cell biology such as self-renewal and cell cycle regulation and somatic cell reprogramming.
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Abstract
At the time of implantation, the mouse blastocyst has developed three cell lineages: the epiblast (Epi), the primitive endoderm (PrE), and the trophectoderm (TE). The PrE and TE are extraembryonic tissues but their interactions with the Epi are critical to sustain embryonic growth, as well as to pattern the embryo. We review here the cellular and molecular events that lead to the production of PrE and Epi lineages and discuss the different hypotheses that are proposed for the induction of these cell types. In the second part, we report the current knowledge about the epithelialization of the PrE.
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Plasticity of the inner cell mass in mouse blastocyst is restricted by the activity of FGF/MAPK pathway. Sci Rep 2017; 7:15136. [PMID: 29123210 PMCID: PMC5680175 DOI: 10.1038/s41598-017-15427-0] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2017] [Accepted: 10/25/2017] [Indexed: 12/20/2022] Open
Abstract
In order to ensure successful development, cells of the early mammalian embryo must differentiate to either trophectoderm (TE) or inner cell mass (ICM), followed by epiblast (EPI) or primitive endoderm (PE) specification within the ICM. Here, we deciphered the mechanism that assures the correct order of these sequential cell fate decisions. We revealed that TE-deprived ICMs derived from 32-cell blastocysts are still able to reconstruct TE during in vitro culture, confirming totipotency of ICM cells at this stage. ICMs isolated from more advanced blastocysts no longer retain totipotency, failing to form TE and generating PE on their surface. We demonstrated that the transition from full potency to lineage priming is prevented by inhibition of the FGF/MAPK signalling pathway. Moreover, we found that after this first restriction step, ICM cells still retain fate flexibility, manifested by ability to convert their fate into an alternative lineage (PE towards EPI and vice versa), until peri-implantation stage.
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