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Boutourlinsky K, Allègre N, Chazaud C. Ex Vivo Culture for Preimplantation Mouse Embryo to Analyze Pluripotency. Methods Mol Biol 2021; 2214:1-10. [PMID: 32944899 DOI: 10.1007/978-1-0716-0958-3_1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
A couple of days after fertilization of a mouse oocyte by a sperm, two sequential cell differentiation events segregate pluripotent cells that can be identified by the presence of specific markers. Early mammalian embryos are relatively easy to recover as they are not yet implanted in the uterus matrix. Several decades of experimentation have enabled to find appropriate media to culture them, and therefore provide an excellent way to test different experimental setups such as the use of signaling inhibitors. We provide here a commonly used protocol to culture preimplantation embryos as well as a method to detect pluripotent cells in blastocysts.
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Affiliation(s)
- Katia Boutourlinsky
- Institut GReD, Université Clermont Auvergne, CNRS, Inserm, Clermont-Ferrand, 63000, France
| | - Nicolas Allègre
- Institut GReD, Université Clermont Auvergne, CNRS, Inserm, Clermont-Ferrand, 63000, France
| | - Claire Chazaud
- Institut GReD, Université Clermont Auvergne, CNRS, Inserm, Clermont-Ferrand, 63000, France.
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52
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Fiorentino J, Torres-Padilla ME, Scialdone A. Measuring and Modeling Single-Cell Heterogeneity and Fate Decision in Mouse Embryos. Annu Rev Genet 2020; 54:167-187. [PMID: 32867543 DOI: 10.1146/annurev-genet-021920-110200] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Cellular heterogeneity is a property of any living system; however, its relationship with cellular fate decision remains an open question. Recent technological advances have enabled valuable insights, especially in complex systems such as the mouse embryo. In this review, we discuss recent studies that characterize cellular heterogeneity at different levels during mouse development, from the two-cell stage up to gastrulation. In addition to key experimental findings, we review mathematical modeling approaches that help researchers interpret these findings. Disentangling the role of heterogeneity in cell fate decision will likely rely on the refined integration of experiments, large-scale omics data, and mathematical modeling, complemented by the use of synthetic embryos and gastruloids as promising in vitro models.
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Affiliation(s)
- Jonathan Fiorentino
- Institute of Epigenetics and Stem Cells (IES), Helmholtz Zentrum München, D-81377 München, Germany; .,Institute of Functional Epigenetics (IFE) and Institute of Computational Biology (ICB), Helmholtz Zentrum München, D-85764 Neuherberg, Germany
| | - Maria-Elena Torres-Padilla
- Institute of Epigenetics and Stem Cells (IES), Helmholtz Zentrum München, D-81377 München, Germany; .,Faculty of Biology, Ludwig-Maximilians Universität, D-82152 Planegg-Martinsried, Germany
| | - Antonio Scialdone
- Institute of Epigenetics and Stem Cells (IES), Helmholtz Zentrum München, D-81377 München, Germany; .,Institute of Functional Epigenetics (IFE) and Institute of Computational Biology (ICB), Helmholtz Zentrum München, D-85764 Neuherberg, Germany
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53
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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: 53] [Impact Index Per Article: 13.3] [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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54
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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: 54] [Impact Index Per Article: 13.5] [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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55
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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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56
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Riveiro AR, Brickman JM. From pluripotency to totipotency: an experimentalist's guide to cellular potency. Development 2020; 147:147/16/dev189845. [PMID: 32847824 DOI: 10.1242/dev.189845] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2020] [Accepted: 07/16/2020] [Indexed: 12/12/2022]
Abstract
Embryonic stem cells (ESCs) are derived from the pre-implantation mammalian blastocyst. At this point in time, the newly formed embryo is concerned with the generation and expansion of both the embryonic lineages required to build the embryo and the extra-embryonic lineages that support development. When used in grafting experiments, embryonic cells from early developmental stages can contribute to both embryonic and extra-embryonic lineages, but it is generally accepted that ESCs can give rise to only embryonic lineages. As a result, they are referred to as pluripotent, rather than totipotent. Here, we consider the experimental potential of various ESC populations and a number of recently identified in vitro culture systems producing states beyond pluripotency and reminiscent of those observed during pre-implantation development. We also consider the nature of totipotency and the extent to which cell populations in these culture systems exhibit this property.
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Affiliation(s)
- Alba Redó Riveiro
- Novo Nordisk Foundation Center for Stem Cell Biology (DanStem), University of Copenhagen, Blegdamsvej 3B, DK-2200 Copenhagen N, Denmark
| | - Joshua Mark Brickman
- Novo Nordisk Foundation Center for Stem Cell Biology (DanStem), University of Copenhagen, Blegdamsvej 3B, DK-2200 Copenhagen N, Denmark
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57
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Hashimoto M, Sasaki H. Cell competition controls differentiation in mouse embryos and stem cells. Curr Opin Cell Biol 2020; 67:1-8. [PMID: 32763500 DOI: 10.1016/j.ceb.2020.07.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2020] [Revised: 07/01/2020] [Accepted: 07/07/2020] [Indexed: 12/14/2022]
Abstract
Cell competition is a short-range intercellular communication, in which cells compare their fitness with that of their neighbors and eliminate the cells with relatively lower fitness. It is considered important for the formation and maintenance of healthy tissues; however, its exact role during development, especially in mammals, has been obscure. Recent studies in mouse embryonic epiblast and skin tissues revealed that cell differentiation in early embryos and stem cell proliferation tends to produce suboptimal cells, especially during early developmental stages. Cell competition occurs at multiple stages and via multiple mechanisms during development to ensure elimination of such low-quality cells. Thus, quality control via cell competition supports correct development by overcoming the heterogeneity produced during cell differentiation and stem cell proliferation.
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Affiliation(s)
- Masakazu Hashimoto
- Graduate School of Frontier Biosciences, Osaka University, Suita, Osaka 565-0871, Japan
| | - Hiroshi Sasaki
- Graduate School of Frontier Biosciences, Osaka University, Suita, Osaka 565-0871, Japan.
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58
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Saiz N, Mora-Bitria L, Rahman S, George H, Herder JP, Garcia-Ojalvo J, Hadjantonakis AK. Growth-factor-mediated coupling between lineage size and cell fate choice underlies robustness of mammalian development. eLife 2020; 9:e56079. [PMID: 32720894 PMCID: PMC7513828 DOI: 10.7554/elife.56079] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2020] [Accepted: 07/24/2020] [Indexed: 01/03/2023] Open
Abstract
Precise control and maintenance of population size is fundamental for organismal development and homeostasis. The three cell types of the mammalian blastocyst are generated in precise proportions over a short time, suggesting a mechanism to ensure a reproducible outcome. We developed a minimal mathematical model demonstrating growth factor signaling is sufficient to guarantee this robustness and which anticipates an embryo's response to perturbations in lineage composition. Addition of lineage-restricted cells both in vivo and in silico, causes a shift of the fate of progenitors away from the supernumerary cell type, while eliminating cells using laser ablation biases the specification of progenitors toward the targeted cell type. Finally, FGF4 couples fate decisions to lineage composition through changes in local growth factor concentration, providing a basis for the regulative abilities of the early mammalian embryo whereby fate decisions are coordinated at the population level to robustly generate tissues in the right proportions.
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Affiliation(s)
- Néstor Saiz
- Developmental Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, United States
| | - Laura Mora-Bitria
- Department of Experimental and Health Sciences, Universitat Pompeu Fabra, Barcelona Biomedical Research Park, Barcelona, Spain
| | - Shahadat Rahman
- Developmental Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, United States
| | - Hannah George
- Developmental Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, United States
| | - Jeremy P Herder
- Developmental Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, United States
| | - Jordi Garcia-Ojalvo
- Department of Experimental and Health Sciences, Universitat Pompeu Fabra, Barcelona Biomedical Research Park, Barcelona, Spain
| | - Anna-Katerina Hadjantonakis
- Developmental Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, United States
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59
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Płusa B, Piliszek A. Common principles of early mammalian embryo self-organisation. Development 2020; 147:147/14/dev183079. [PMID: 32699138 DOI: 10.1242/dev.183079] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Pre-implantation mammalian development unites extreme plasticity with a robust outcome: the formation of a blastocyst, an organised multi-layered structure ready for implantation. The process of blastocyst formation is one of the best-known examples of self-organisation. The first three cell lineages in mammalian development specify and arrange themselves during the morphogenic process based on cell-cell interactions. Despite decades of research, the unifying principles driving early mammalian development are still not fully defined. Here, we discuss the role of physical forces, and molecular and cellular mechanisms, in driving self-organisation and lineage formation that are shared between eutherian mammals.
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Affiliation(s)
- Berenika Płusa
- Faculty of Biology, Medicine and Health (FBMH), Division of Developmental Biology & Medicine, University of Manchester, Michael Smith Building, Oxford Road, Manchester, M13 9PT, UK
| | - Anna Piliszek
- Department of Experimental Embryology, Institute of Genetics and Animal Biotechnology, Polish Academy of Sciences, Jastrzebiec, Postepu 36A, 05-552 Magdalenka, Poland
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60
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Fischer SC, Corujo-Simon E, Lilao-Garzon J, Stelzer EHK, Muñoz-Descalzo S. The transition from local to global patterns governs the differentiation of mouse blastocysts. PLoS One 2020; 15:e0233030. [PMID: 32413083 PMCID: PMC7228118 DOI: 10.1371/journal.pone.0233030] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2020] [Accepted: 04/27/2020] [Indexed: 01/06/2023] Open
Abstract
During mammalian blastocyst development, inner cell mass (ICM) cells differentiate into epiblast (Epi) or primitive endoderm (PrE). These two fates are characterized by the expression of the transcription factors NANOG and GATA6, respectively. Here, we investigate the spatio-temporal distribution of NANOG and GATA6 expressing cells in the ICM of the mouse blastocysts with quantitative three-dimensional single cell-based neighbourhood analyses. We define the cell neighbourhood by local features, which include the expression levels of both fate markers expressed in each cell and its neighbours, and the number of neighbouring cells. We further include the position of a cell relative to the centre of the ICM as a global positional feature. Our analyses reveal a local three-dimensional pattern that is already present in early blastocysts: 1) Cells expressing the highest NANOG levels are surrounded by approximately nine neighbours, while 2) cells expressing GATA6 cluster according to their GATA6 levels. This local pattern evolves into a global pattern in the ICM that starts to emerge in mid blastocysts. We show that FGF/MAPK signalling is involved in the three-dimensional distribution of the cells and, using a mutant background, we further show that the GATA6 neighbourhood is regulated by NANOG. Our quantitative study suggests that the three-dimensional cell neighbourhood plays a role in Epi and PrE precursor specification. Our results highlight the importance of analysing the three-dimensional cell neighbourhood while investigating cell fate decisions during early mouse embryonic development.
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Affiliation(s)
- Sabine C. Fischer
- Physikalische Biologie, Buchmann Institute for Molecular Life Sciences, Goethe-Universität Frankfurt am Main, Frankfurt am Main, Germany
| | - Elena Corujo-Simon
- Department of Biology and Biochemistry, University of Bath, Bath, England, United Kingdom
| | - Joaquin Lilao-Garzon
- Department of Biology and Biochemistry, University of Bath, Bath, England, United Kingdom
- Instituto Universitario de Investigaciones Biomédicas y Sanitarias, Universidad Las Palmas de Gran Canaria, Las Palmas de Gran Canaria, Las Palmas de Gran Canaria, Spain
| | - Ernst H. K. Stelzer
- Physikalische Biologie, 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, England, United Kingdom
- Instituto Universitario de Investigaciones Biomédicas y Sanitarias, Universidad Las Palmas de Gran Canaria, Las Palmas de Gran Canaria, Las Palmas de Gran Canaria, Spain
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61
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Niwayama R, Moghe P, Liu YJ, Fabrèges D, Buchholz F, Piel M, Hiiragi T. A Tug-of-War between Cell Shape and Polarity Controls Division Orientation to Ensure Robust Patterning in the Mouse Blastocyst. Dev Cell 2019; 51:564-574.e6. [PMID: 31735668 PMCID: PMC6892278 DOI: 10.1016/j.devcel.2019.10.012] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2019] [Revised: 07/04/2019] [Accepted: 10/14/2019] [Indexed: 01/08/2023]
Abstract
Oriented cell division patterns tissues by modulating cell position and fate. While cell geometry, junctions, cortical tension, and polarity are known to control division orientation, relatively little is known about how these are coordinated to ensure robust patterning. Here, we systematically characterize cell division, volume, and shape changes during mouse pre-implantation development by in toto live imaging. The analysis leads us to a model in which the apical domain competes with cell shape to determine division orientation. Two key predictions of the model are verified experimentally: when outside cells of the 16-cell embryo are released from cell shape asymmetry, the axis of division is guided by the apical domain. Conversely, orientation cues from the apical domain can be overcome by applied shape asymmetry in the 8-cell embryo. We propose that such interplay between cell shape and polarity in controlling division orientation ensures robust patterning of the blastocyst and possibly other tissues. Cell division, volume, and shape changes are characterized by in toto embryo imaging Cell shape and the apical domain compete to determine division orientation Two key predictions of the model are verified experimentally The tug-of-war mechanism ensures robust cell allocation and patterning
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Affiliation(s)
- Ritsuya Niwayama
- European Molecular Biology Laboratory (EMBL), Heidelberg, Germany
| | - Prachiti Moghe
- European Molecular Biology Laboratory (EMBL), Heidelberg, Germany
| | - Yan-Jun Liu
- UMR 144 Institut Curie, Institut Pierre Gilles de Gennes for Microfluidics, Paris, France
| | - Dimitri Fabrèges
- European Molecular Biology Laboratory (EMBL), Heidelberg, Germany
| | - Frank Buchholz
- Medical Systems Biology, UCC, University Hospital and Medical Faculty Carl Gustav Carus, TU Dresden, Dresden, Germany
| | - Matthieu Piel
- UMR 144 Institut Curie, Institut Pierre Gilles de Gennes for Microfluidics, Paris, France
| | - Takashi Hiiragi
- European Molecular Biology Laboratory (EMBL), Heidelberg, Germany; Institute for Advanced Study of Human Biology (WPI-ASHBi), Kyoto University, Kyoto, Japan.
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62
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Frum T, Watts JL, Ralston A. TEAD4, YAP1 and WWTR1 prevent the premature onset of pluripotency prior to the 16-cell stage. Development 2019; 146:dev.179861. [PMID: 31444221 PMCID: PMC6765126 DOI: 10.1242/dev.179861] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2019] [Accepted: 08/09/2019] [Indexed: 12/15/2022]
Abstract
In mice, pluripotent cells are thought to derive from cells buried inside the embryo around the 16-cell stage. Sox2 is the only pluripotency gene known to be expressed specifically within inside cells at this stage. To understand how pluripotency is established, we therefore investigated the mechanisms regulating the initial activation of Sox2 expression. Surprisingly, Sox2 expression initiated normally in the absence of both Nanog and Oct4 (Pou5f1), highlighting differences between embryo and stem cell models of pluripotency. However, we observed precocious ectopic expression of Sox2 prior to the 16-cell stage in the absence of Yap1, Wwtr1 and Tead4. Interestingly, the repression of premature Sox2 expression was sensitive to LATS kinase activity, even though LATS proteins normally do not limit activity of TEAD4, YAP1 and WWTR1 during these early stages. Finally, we present evidence for direct transcriptional repression of Sox2 by YAP1, WWTR1 and TEAD4. Taken together, our observations reveal that, while embryos are initially competent to express Sox2 as early as the four-cell stage, transcriptional repression prevents the premature expression of Sox2, thereby restricting the pluripotency program to the stage when inside cells are first created. Highlighted Article: The pluripotency marker SOX2 is not initially regulated by OCT4 and NANOG, but by HIPPO pathway members during the first 2 days of mouse embryogenesis.
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Affiliation(s)
- Tristan Frum
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI 48824, USA
| | - Jennifer L Watts
- Physiology Graduate Program, Michigan State University, East Lansing, MI 48824, USA.,Reproductive and Developmental Biology Training Program, Michigan State University, East Lansing, MI 48824, USA
| | - Amy Ralston
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI 48824, USA .,Reproductive and Developmental Biology Training Program, Michigan State University, East Lansing, MI 48824, USA
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63
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Hashimoto M, Sasaki H. Epiblast Formation by TEAD-YAP-Dependent Expression of Pluripotency Factors and Competitive Elimination of Unspecified Cells. Dev Cell 2019; 50:139-154.e5. [PMID: 31204175 DOI: 10.1016/j.devcel.2019.05.024] [Citation(s) in RCA: 78] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2018] [Revised: 03/29/2019] [Accepted: 05/10/2019] [Indexed: 01/15/2023]
Abstract
The epiblast is a pluripotent cell population first formed in preimplantation embryos, and its quality is important for proper development. Here, we examined the mechanisms of epiblast formation and found that the Hippo pathway transcription factor TEAD and its coactivator YAP regulate expression of pluripotency factors. After specification of the inner cell mass, YAP accumulates in the nuclei and activates TEAD. TEAD activity is required for strong expression of pluripotency factors and is variable in the forming epiblast. Cells showing low TEAD activity are eliminated from the epiblast through cell competition. Pluripotency factor expression and MYC control cell competition downstream of TEAD activity. Cell competition eliminates unspecified cells and is required for proper organization of the epiblast. These results suggest that induction of pluripotency factors by TEAD activity and elimination of unspecified cells via cell competition ensure the production of an epiblast with naive pluripotency.
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Affiliation(s)
- Masakazu Hashimoto
- Laboratory for Embryogenesis, Graduate School of Frontier Biosciences, Osaka University, Suita, Osaka 565-0871, Japan
| | - Hiroshi Sasaki
- Laboratory for Embryogenesis, Graduate School of Frontier Biosciences, Osaka University, Suita, Osaka 565-0871, Japan.
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64
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West JD, Tang PC, Everett CA, MacKay GE, Flockhart JH, Keighren MA. Re-evaluation of the causes of variation among mouse aggregation chimaeras. Biol Open 2019; 8:8/5/bio042804. [PMID: 31147312 PMCID: PMC6550066 DOI: 10.1242/bio.042804] [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: 11/01/2022] Open
Abstract
The composition of adult mouse aggregation chimaeras is much more variable than X-inactivation mosaics. An early theoretical model proposed that almost all the extra variation in chimaeras arises, before X-inactivation occurs, by spatially constrained, geometrical allocation of inner cell mass (ICM) cells to the epiblast and primitive endoderm (PrE). However, this is inconsistent with more recent embryological evidence. Analysis of published results for chimaeric blastocysts and mid-gestation chimaeras suggested that some variation exists among chimaeric morulae and more variation arises both when morula cells are allocated to the ICM versus the trophectoderm (TE) and when ICM cells are allocated to the epiblast versus the PrE. Computer simulation results were also consistent with the conclusion that stochastic allocation of cells to blastocyst lineages in two steps, without the type of geometrical sampling that was originally proposed, could cause a wide variation in chimaeric epiblast composition. Later allocation events will cause additional variation among both chimaeras and X-inactivation mosaics. We also suggest that previously published U-shaped frequency distributions for chimaeric placenta composition might be explained by how TE cells are allocated to the polar TE and/or the subsequent movement of cells from polar TE to mural TE.
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Affiliation(s)
- John D West
- Genes and Development Group, Centre for Integrative Physiology, Clinical Sciences, University of Edinburgh Medical School, Hugh Robson Building, George Square, Edinburgh EH8 9XD, UK
| | - Pin-Chi Tang
- Genes and Development Group, Centre for Integrative Physiology, Clinical Sciences, University of Edinburgh Medical School, Hugh Robson Building, George Square, Edinburgh EH8 9XD, UK
| | - Clare A Everett
- Genes and Development Group, Centre for Integrative Physiology, Clinical Sciences, University of Edinburgh Medical School, Hugh Robson Building, George Square, Edinburgh EH8 9XD, UK
| | - Gillian E MacKay
- Genes and Development Group, Centre for Integrative Physiology, Clinical Sciences, University of Edinburgh Medical School, Hugh Robson Building, George Square, Edinburgh EH8 9XD, UK
| | - Jean H Flockhart
- Genes and Development Group, Centre for Integrative Physiology, Clinical Sciences, University of Edinburgh Medical School, Hugh Robson Building, George Square, Edinburgh EH8 9XD, UK
| | - Margaret A Keighren
- Genes and Development Group, Centre for Integrative Physiology, Clinical Sciences, University of Edinburgh Medical School, Hugh Robson Building, George Square, Edinburgh EH8 9XD, UK
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65
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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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66
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Filimonow K, Saiz N, Suwińska A, Wyszomirski T, Grabarek JB, Ferretti E, Piliszek A, Plusa B, Maleszewski M. No evidence of involvement of E-cadherin in cell fate specification or the segregation of Epi and PrE in mouse blastocysts. PLoS One 2019; 14:e0212109. [PMID: 30735538 PMCID: PMC6368326 DOI: 10.1371/journal.pone.0212109] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2018] [Accepted: 01/27/2019] [Indexed: 12/13/2022] Open
Abstract
During preimplantation mouse development stages, emerging pluripotent epiblast (Epi) and extraembryonic primitive endoderm (PrE) cells are first distributed in the blastocyst in a "salt-and-pepper" manner before they segregate into separate layers. As a result of segregation, PrE cells become localised on the surface of the inner cell mass (ICM), and the Epi is enclosed by the PrE on one side and by the trophectoderm on the other. During later development, a subpopulation of PrE cells migrates away from the ICM and forms the parietal endoderm (PE), while cells remaining in contact with the Epi form the visceral endoderm (VE). Here, we asked: what are the mechanisms mediating Epi and PrE cell segregation and the subsequent VE vs PE specification? Differences in cell adhesion have been proposed; however, we demonstrate that the levels of plasma membrane-bound E-cadherin (CDH1, cadherin 1) in Epi and PrE cells only differ after the segregation of these lineages within the ICM. Moreover, manipulating E-cadherin levels did not affect lineage specification or segregation, thus failing to confirm its role during these processes. Rather, we report changes in E-cadherin localisation during later PrE-to-PE transition which are accompanied by the presence of Vimentin and Twist, supporting the hypothesis that an epithelial-to-mesenchymal transition process occurs in the mouse peri-implantation blastocyst.
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Affiliation(s)
- Katarzyna Filimonow
- Department of Embryology, Faculty of Biology, The University of Warsaw, I. Miecznikowa, Warsaw, Poland
- Division of Developmental Biology and Medicine, The University of Manchester, Oxford Road, Manchester, United Kingdom
- Department of Experimental Embryology, Institute of Genetics and Animal Breeding, Polish Academy of Sciences, Postępu 36a, Jastrzębiec, Poland
| | - Nestor Saiz
- Division of Developmental Biology and Medicine, The University of Manchester, Oxford Road, Manchester, United Kingdom
| | - Aneta Suwińska
- Department of Embryology, Faculty of Biology, The University of Warsaw, I. Miecznikowa, Warsaw, Poland
| | - Tomasz Wyszomirski
- Faculty of Biology, Biological and Chemical Research Centre, The University of Warsaw, Zwirki i Wigury, Warsaw, Poland
| | - Joanna B. Grabarek
- Division of Developmental Biology and Medicine, The University of Manchester, Oxford Road, Manchester, United Kingdom
| | - Elisabetta Ferretti
- The Danish Stem Cell Centre (DanStem), University of Copenhagen, Blegdamsvej, Copenhagen N, Denmark
| | - Anna Piliszek
- Department of Experimental Embryology, Institute of Genetics and Animal Breeding, Polish Academy of Sciences, Postępu 36a, Jastrzębiec, Poland
| | - Berenika Plusa
- Division of Developmental Biology and Medicine, The University of Manchester, Oxford Road, Manchester, United Kingdom
- * E-mail: (MM); (BP)
| | - Marek Maleszewski
- Department of Embryology, Faculty of Biology, The University of Warsaw, I. Miecznikowa, Warsaw, Poland
- * E-mail: (MM); (BP)
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67
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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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68
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Simon CS, Zhang L, Wu T, Cai W, Saiz N, Nowotschin S, Cai CL, Hadjantonakis AK. A Gata4 nuclear GFP transcriptional reporter to study endoderm and cardiac development in the mouse. Biol Open 2018; 7:bio.036517. [PMID: 30530745 PMCID: PMC6310872 DOI: 10.1242/bio.036517] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
The GATA zinc-finger transcription factor GATA4 is expressed in a variety of tissues during mouse embryonic development and in adult organs. These include the primitive endoderm of the blastocyst, visceral endoderm of the early post-implantation embryo, as well as lateral plate mesoderm, developing heart, liver, lung and gonads. Here, we generate a novel Gata4 targeted allele used to generate both a Gata4H2B-GFP transcriptional reporter and a Gata4FLAG fusion protein to analyse dynamic expression domains. We demonstrate that the Gata4H2B-GFP transcriptional reporter faithfully recapitulates known sites of Gata4 mRNA expression and correlates with endogenous GATA4 protein levels. This reporter labels nuclei of Gata4 expressing cells and is suitable for time-lapse imaging and single cell analyses. As such, this Gata4H2B-GFP allele will be a useful tool for studying Gata4 expression and transcriptional regulation.This article has an associated First Person interview with the first author of the paper.
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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
| | - Lu Zhang
- Department of Developmental and Regenerative Biology, The Mindich Child Health and Development Institute, and The Black Family Stem Cell Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Tao Wu
- Developmental Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA.,School of Basic Medicine and Clinical Pharmacy, China Pharmaceutical University, Nanjing 211198, China
| | - Weibin Cai
- Department of Developmental and Regenerative Biology, The Mindich Child Health and Development Institute, and The Black Family Stem Cell Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Nestor Saiz
- Developmental Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
| | - Sonja Nowotschin
- Developmental Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
| | - Chen-Leng Cai
- Department of Developmental and Regenerative Biology, The Mindich Child Health and Development Institute, and The Black Family Stem Cell Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Anna-Katerina Hadjantonakis
- Developmental Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
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69
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Abstract
Establishing the different lineages of the early mammalian embryo takes place over several days and several rounds of cell divisions from the fertilized egg. The resulting blastocyst contains the pluripotent cells of the epiblast, from which embryonic stem cells can be derived, as well as the extraembryonic lineages required for a mammalian embryo to survive in the uterine environment. The dynamics of the cellular and genetic interactions controlling the initiation and maintenance of these lineages in the mouse embryo are increasingly well understood through application of the tools of single-cell genomics, gene editing, and in vivo imaging. Exploring the similarities and differences between mouse and human development will be essential for translation of these findings into new insights into human biology, derivation of stem cells, and improvements in fertility treatments.
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Affiliation(s)
- Janet Rossant
- Program in Stem Cell and Developmental Biology, Hospital for Sick Children, Toronto, Ontario M5G 0A4, Canada
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario M5S 1A8, Canada
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70
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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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71
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Characterizing Inner Pressure and Stiffness of Trophoblast and Inner Cell Mass of Blastocysts. Biophys J 2018; 115:2443-2450. [PMID: 30509858 DOI: 10.1016/j.bpj.2018.11.008] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2018] [Revised: 10/23/2018] [Accepted: 11/05/2018] [Indexed: 12/14/2022] Open
Abstract
It has long been recognized that mechanical forces underlie mammalian embryonic shape changes. Before gastrulation, the blastocyst embryo undergoes significant shape changes, namely, the blastocyst cavity emerges and expands, and the inner cell mass (ICM) forms and changes in shape. The embryo's inner pressure has been hypothesized to be the driving mechanical input that causes the expansion of the blastocyst cavity and the shape changes of the ICM. However, how the inner pressure and the mechanics of the trophoblast and the ICM change during development is unknown because of the lack of a suitable tool for quantitative characterization. This work presents a laser-assisted magnetic tweezer technique for measuring the inner pressure and Young's modulus of the trophoblast and ICM of the blastocyst-stage mouse embryo. The results quantitatively showed that the inner pressure and Young's modulus of the trophoblast and ICM all increase during progression of mouse blastocysts, providing useful data for understanding how mechanical factors are physiologically integrated with other cues to direct embryo development.
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72
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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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73
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Abstract
We present an overview of symmetry breaking in early mammalian development as a continuous process from compaction to specification of the body axes. While earlier studies have focused on individual symmetry-breaking events, recent advances enable us to explore progressive symmetry breaking during early mammalian development. Although we primarily discuss embryonic development of the mouse, as it is the best-studied mammalian model system to date, we also highlight the shared and distinct aspects between different mammalian species. Finally, we discuss how insights gained from studying mammalian development can be generalized in light of self-organization principles. With this review, we hope to highlight new perspectives in studying symmetry breaking and self-organization in multicellular systems.
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Affiliation(s)
- Hui Ting Zhang
- European Molecular Biology Laboratory, 69117 Heidelberg, Germany;
| | - Takashi Hiiragi
- European Molecular Biology Laboratory, 69117 Heidelberg, Germany;
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74
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Pfeffer PL. Building Principles for Constructing a Mammalian Blastocyst Embryo. BIOLOGY 2018; 7:biology7030041. [PMID: 30041494 PMCID: PMC6164496 DOI: 10.3390/biology7030041] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/13/2018] [Revised: 07/19/2018] [Accepted: 07/20/2018] [Indexed: 12/16/2022]
Abstract
The self-organisation of a fertilised egg to form a blastocyst structure, which consists of three distinct cell lineages (trophoblast, epiblast and hypoblast) arranged around an off-centre cavity, is unique to mammals. While the starting point (the zygote) and endpoint (the blastocyst) are similar in all mammals, the intervening events have diverged. This review examines and compares the descriptive and functional data surrounding embryonic gene activation, symmetry-breaking, first and second lineage establishment, and fate commitment in a wide range of mammalian orders. The exquisite detail known from mouse embryogenesis, embryonic stem cell studies and the wealth of recent single cell transcriptomic experiments are used to highlight the building principles underlying early mammalian embryonic development.
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Affiliation(s)
- Peter L Pfeffer
- School of Biological Sciences, Victoria University of Wellington, Wellington 6012, New Zealand.
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75
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Morgani SM, Saiz N, Garg V, Raina D, Simon CS, Kang M, Arias AM, Nichols J, Schröter C, Hadjantonakis AK. A Sprouty4 reporter to monitor FGF/ERK signaling activity in ESCs and mice. Dev Biol 2018; 441:104-126. [PMID: 29964027 DOI: 10.1016/j.ydbio.2018.06.017] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2018] [Revised: 06/25/2018] [Accepted: 06/25/2018] [Indexed: 12/31/2022]
Abstract
The FGF/ERK signaling pathway is highly conserved throughout evolution and plays fundamental roles during embryonic development and in adult organisms. While a plethora of expression data exists for ligands, receptors and pathway regulators, we know little about the spatial organization or dynamics of signaling in individual cells within populations. To this end we developed a transcriptional readout of FGF/ERK activity by targeting a histone H2B-linked Venus fluorophore to the endogenous locus of Spry4, an early pathway target, and generated Spry4H2B-Venus embryonic stem cells (ESCs) and a derivative mouse line. The Spry4H2B-Venus reporter was heterogeneously expressed within ESC cultures and responded to FGF/ERK signaling manipulation. In vivo, the Spry4H2B-Venus reporter recapitulated the expression pattern of Spry4 and localized to sites of known FGF/ERK activity including the inner cell mass of the pre-implantation embryo and the limb buds, somites and isthmus of the post-implantation embryo. Additionally, we observed highly localized reporter expression within adult organs. Genetic and chemical disruption of FGF/ERK signaling, in vivo in pre- and post-implantation embryos, abrogated Venus expression establishing the reporter as an accurate signaling readout. This tool will provide new insights into the dynamics of the FGF/ERK signaling pathway during mammalian development.
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Affiliation(s)
- Sophie M Morgani
- Developmental Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA; Wellcome Trust-Medical Research Council Centre for Stem Cell Research, University of Cambridge, Tennis Court Road, Cambridge CB2 1QR, UK
| | - Nestor Saiz
- Developmental Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
| | - Vidur Garg
- Developmental Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA; Biochemistry, Cell and Molecular Biology Program, Weill Cornell Graduate School of Medical Sciences, 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
| | - Claire S Simon
- Developmental Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
| | - Minjung Kang
- Developmental Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA; Biochemistry, Cell and Molecular Biology Program, Weill Cornell Graduate School of Medical Sciences, New York, NY 10065, USA
| | | | - Jennifer Nichols
- Wellcome Trust-Medical Research Council Centre for Stem Cell Research, University of Cambridge, Tennis Court Road, Cambridge CB2 1QR, UK
| | - 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; Biochemistry, Cell and Molecular Biology Program, Weill Cornell Graduate School of Medical Sciences, New York, NY 10065, USA.
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76
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Gleicher N. Expected advances in human fertility treatments and their likely translational consequences. J Transl Med 2018; 16:149. [PMID: 29866181 PMCID: PMC5987489 DOI: 10.1186/s12967-018-1525-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2018] [Accepted: 05/26/2018] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND Due to rapid research progress in reproductive biology and reproductive clinical endocrinology, many human infertility treatments are close to potential breakthroughs and translational applications. We here review current barriers, where such breakthroughs will likely come from, what they will entail, and their potential clinical applications. MAIN TEXT The radical nature of change will primarily benefit older women, reduce fertility treatment costs and thereby expand access to treatment. A still widely overlooked prerequisite for implantation and normal pregnancy maintenance is timely development of maternal immunological tolerance toward an implanting paternal semi-allograft, if malfunctioning associated with implantation failure and pregnancy loss, while premature termination of tolerance appears associated with premature labor, pre-eclampsia/eclampsia and gestoses of pregnancy. Common denominators between pregnancy and invasive malignancies have again been attracting attention, suggesting that, like in malignant tumors, degrees of embryo aneuploidy may affect invasiveness and ability to "disarm" the immune system's innate response against implanting embryos. Linking tolerance to implantation, we offer evidence that the so-called "implantation window" is likely immunological rather than hormonally defined. CONCLUSIONS Because many here outlined treatment changes will disproportionally benefit older women, they will exert a pronounced effect on society, as increasing numbers of women at grandparental ages will become mothers.
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Affiliation(s)
- Norbert Gleicher
- The CHR, 21 East 69th Street, New York, NY, 10021, USA.
- The Foundation for Reproductive Medicine, New York, NY, 10021, USA.
- Laboratory for Stem Cell Biology and Molecular Embryology, Rockefeller University, New York, NY, 10065, USA.
- Department of Obstetrics and Gynecology, Vienna Medical School, 1090, Vienna, Austria.
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77
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Simon CS, Hadjantonakis AK, Schröter C. Making lineage decisions with biological noise: Lessons from the early mouse embryo. WILEY INTERDISCIPLINARY REVIEWS-DEVELOPMENTAL BIOLOGY 2018; 7:e319. [PMID: 29709110 DOI: 10.1002/wdev.319] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2017] [Revised: 02/09/2018] [Accepted: 03/13/2018] [Indexed: 12/18/2022]
Abstract
Understanding how individual cells make fate decisions that lead to the faithful formation and homeostatic maintenance of tissues is a fundamental goal of contemporary developmental and stem cell biology. Seemingly uniform populations of stem cells and multipotent progenitors display a surprising degree of heterogeneity, primarily originating from the inherent stochastic nature of molecular processes underlying gene expression. Despite this heterogeneity, lineage decisions result in tissues of a defined size and with consistent proportions of differentiated cell types. Using the early mouse embryo as a model we review recent developments that have allowed the quantification of molecular intercellular heterogeneity during cell differentiation. We first discuss the relationship between these heterogeneities and developmental cellular potential. We then review recent theoretical approaches that formalize the mechanisms underlying fate decisions in the inner cell mass of the blastocyst stage embryo. These models build on our extensive knowledge of the genetic control of fate decisions in this system and will become essential tools for a rigorous understanding of the connection between noisy molecular processes and reproducible outcomes at the multicellular level. We conclude by suggesting that cell-to-cell communication provides a mechanism to exploit and buffer intercellular variability in a self-organized process that culminates in the reproducible formation of the mature mammalian blastocyst stage embryo that is ready for implantation into the maternal uterus. This article is categorized under: Gene Expression and Transcriptional Hierarchies > Cellular Differentiation Establishment of Spatial and Temporal Patterns > Regulation of Size, Proportion, and Timing Gene Expression and Transcriptional Hierarchies > Gene Networks and Genomics Gene Expression and Transcriptional Hierarchies > Quantitative Methods and Models.
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Affiliation(s)
- Claire S Simon
- Developmental Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Anna-Katerina Hadjantonakis
- Developmental Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Christian Schröter
- Department of Systemic Cell Biology, Max Planck Institute of Molecular Physiology, Dortmund, Germany
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78
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Meng Y, Moore R, Tao W, Smith ER, Tse JD, Caslini C, Xu XX. GATA6 phosphorylation by Erk1/2 propels exit from pluripotency and commitment to primitive endoderm. Dev Biol 2018; 436:55-65. [PMID: 29454706 PMCID: PMC5912698 DOI: 10.1016/j.ydbio.2018.02.007] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2017] [Revised: 02/13/2018] [Accepted: 02/13/2018] [Indexed: 02/07/2023]
Abstract
The transcription factor GATA6 and the Fgf/Ras/MAPK signaling pathway are essential for the development of the primitive endoderm (PrE), one of the two lineages derived from the pluripotent inner cell mass (ICM) of mammalian blastocysts. A mutant mouse line in which Gata6-coding exons are replaced with H2BGFP (histone H2B Green Fluorescence Protein fusion protein) was developed to monitor Gata6 promoter activity. In the Gata6-H2BGFP heterozygous blastocysts, the ICM cells that initially had uniform GFP fluorescence signal at E3.5 diverged into two populations by the 64-cell stage, either as the GFP-high PrE or the GFP-low epiblasts (Epi). However in the GATA6-null blastocysts, the originally moderate GFP expression subsided in all ICM cells, indicating that the GATA6 protein is required to maintain its own promoter activity during PrE linage commitment. In embryonic stem cells, expressed GATA6 was shown to bind and activate the Gata6 promoter in PrE differentiation. Mutations of a conserved serine residue (S264) for Erk1/2 phosphorylation in GATA6 protein drastically impacted its ability to activate its own promoter. We conclude that phosphorylation of GATA6 by Erk1/2 compels exit from pluripotent state, and the phosphorylation propels a GATA6 positive feedback regulatory circuit to compel PrE differentiation. Our findings resolve the longstanding question on the dual requirements of GATA6 and Ras/MAPK pathway for PrE commitment of the pluripotent ICM.
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Affiliation(s)
- Yue Meng
- Department of Cell Biology, University of Miami Miller School of Medicine, Miami, FL 33136, USA; Graduate Program in Molecular Cell and Developmental Biology, University of Miami Miller School of Medicine, Miami, FL 33136, USA
| | - Robert Moore
- Department of Cell Biology, University of Miami Miller School of Medicine, Miami, FL 33136, USA
| | - Wensi Tao
- Department of Cell Biology, University of Miami Miller School of Medicine, Miami, FL 33136, USA; Graduate Program in Molecular Cell and Developmental Biology, University of Miami Miller School of Medicine, Miami, FL 33136, USA
| | - Elizabeth R Smith
- Department of Cell Biology, University of Miami Miller School of Medicine, Miami, FL 33136, USA
| | - Jeffrey D Tse
- Department of Cell Biology, University of Miami Miller School of Medicine, Miami, FL 33136, USA; Graduate Program in Molecular Cell and Developmental Biology, University of Miami Miller School of Medicine, Miami, FL 33136, USA
| | - Corrado Caslini
- Department of Pathology, University of Miami Miller School of Medicine, Miami, FL 33136, USA
| | - Xiang-Xi Xu
- Department of Cell Biology, University of Miami Miller School of Medicine, Miami, FL 33136, USA; Graduate Program in Molecular Cell and Developmental Biology, University of Miami Miller School of Medicine, Miami, FL 33136, USA.
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79
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Stirparo GG, Boroviak T, Guo G, Nichols J, Smith A, Bertone P. Integrated analysis of single-cell embryo data yields a unified transcriptome signature for the human pre-implantation epiblast. Development 2018; 145:dev158501. [PMID: 29361568 PMCID: PMC5818005 DOI: 10.1242/dev.158501] [Citation(s) in RCA: 113] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2017] [Accepted: 01/04/2018] [Indexed: 12/13/2022]
Abstract
Single-cell profiling techniques create opportunities to delineate cell fate progression in mammalian development. Recent studies have provided transcriptome data from human pre-implantation embryos, in total comprising nearly 2000 individual cells. Interpretation of these data is confounded by biological factors, such as variable embryo staging and cell-type ambiguity, as well as technical challenges in the collective analysis of datasets produced with different sample preparation and sequencing protocols. Here, we address these issues to assemble a complete gene expression time course spanning human pre-implantation embryogenesis. We identify key transcriptional features over developmental time and elucidate lineage-specific regulatory networks. We resolve post-hoc cell-type assignment in the blastocyst, and define robust transcriptional prototypes that capture epiblast and primitive endoderm lineages. Examination of human pluripotent stem cell transcriptomes in this framework identifies culture conditions that sustain a naïve state pertaining to the inner cell mass. Our approach thus clarifies understanding both of lineage segregation in the early human embryo and of in vitro stem cell identity, and provides an analytical resource for comparative molecular embryology.
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Affiliation(s)
- Giuliano G Stirparo
- Wellcome Trust - Medical Research Council Stem Cell Institute, University of Cambridge, Tennis Court Road, Cambridge CB2 1QR, UK
| | - Thorsten Boroviak
- Wellcome Trust - Medical Research Council Stem Cell Institute, University of Cambridge, Tennis Court Road, Cambridge CB2 1QR, UK
| | - Ge Guo
- Wellcome Trust - Medical Research Council Stem Cell Institute, University of Cambridge, Tennis Court Road, Cambridge CB2 1QR, UK
| | - Jennifer Nichols
- Wellcome Trust - Medical Research Council Stem Cell Institute, University of Cambridge, Tennis Court Road, Cambridge CB2 1QR, UK
- Department of Physiology, Development and Neuroscience, University of Cambridge, Tennis Court Road, Cambridge CB2 3EG, UK
| | - Austin Smith
- Wellcome Trust - Medical Research Council Stem Cell Institute, University of Cambridge, Tennis Court Road, Cambridge CB2 1QR, UK
- Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge CB2 1GA, UK
| | - Paul Bertone
- Wellcome Trust - Medical Research Council Stem Cell Institute, University of Cambridge, Tennis Court Road, Cambridge CB2 1QR, UK
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80
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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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81
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Klimczewska K, Kasperczuk A, Suwińska A. The Regulative Nature of Mammalian Embryos. Curr Top Dev Biol 2018; 128:105-149. [DOI: 10.1016/bs.ctdb.2017.10.010] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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82
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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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83
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Dynamics of lineage commitment revealed by single-cell transcriptomics of differentiating embryonic stem cells. Nat Commun 2017; 8:1096. [PMID: 29061959 PMCID: PMC5653659 DOI: 10.1038/s41467-017-01076-4] [Citation(s) in RCA: 113] [Impact Index Per Article: 16.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2016] [Accepted: 08/15/2017] [Indexed: 01/01/2023] Open
Abstract
Gene expression heterogeneity in the pluripotent state of mouse
embryonic stem cells (mESCs) has been increasingly well-characterized. In contrast,
exit from pluripotency and lineage commitment have not been studied systematically
at the single-cell level. Here we measure the gene expression dynamics of retinoic
acid driven mESC differentiation from pluripotency to lineage commitment, using an
unbiased single-cell transcriptomics approach. We find that the exit from
pluripotency marks the start of a lineage transition as well as a transient phase of
increased susceptibility to lineage specifying signals. Our study reveals several
transcriptional signatures of this phase, including a sharp increase of gene
expression variability and sequential expression of two classes of transcriptional
regulators. In summary, we provide a comprehensive analysis of the exit from
pluripotency and lineage commitment at the single cell level, a potential stepping
stone to improved lineage manipulation through timing of differentiation
cues. Commitment to different fates by differentiating pluripotent cells
depends upon integration of external and internal signals. Here the authors analyse
the entry of mouse embryonic stem cells into retinoic acid-mediated differentiation
using single cell transcriptomics with high temporal resolution.
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84
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Bardot E, Tzavaras N, Benson DL, Dubois NC. Quantitative Whole-mount Immunofluorescence Analysis of Cardiac Progenitor Populations in Mouse Embryos. J Vis Exp 2017:10.3791/56446. [PMID: 29053691 PMCID: PMC6475905 DOI: 10.3791/56446] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
The use of ever-advancing imaging techniques has contributed broadly to our increased understanding of embryonic development. Pre-implantation development and organogenesis are two areas of research that have benefitted greatly from these advances, due to the high quality of data that can be obtained directly from imaging pre-implantation embryos or ex vivo organs. While pre-implantation embryos have yielded data with especially high spatial resolution, later stages have been less amenable to three-dimensional reconstruction. Obtaining high-quality 3D or volumetric data for known embryonic structures in combination with fate mapping or genetic lineage tracing will allow for a more comprehensive analysis of the morphogenetic events taking place during embryogenesis. This protocol describes a whole-mount immunofluorescence approach that allows for the labeling, visualization, and quantification of progenitor cell populations within the developing cardiac crescent, a key structure formed during heart development. The approach is designed in such a way that both cell- and tissue-level information can be obtained. Using confocal microscopy and image processing, this protocol allows for three-dimensional spatial reconstruction of the cardiac crescent, thereby providing the ability to analyze the localization and organization of specific progenitor populations during this critical phase of heart development. Importantly, the use of reference antibodies allows for successive masking of the cardiac crescent and subsequent quantitative measurements of areas within the crescent. This protocol will not only enable a detailed examination of early heart development, but with adaptations should be applicable to most organ systems in the gastrula to early somite stage mouse embryo.
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Affiliation(s)
- Evan Bardot
- Cell, Developmental, and Regenerative Biology Department, Icahn School of Medicine at Mount Sinai; Mindich Child Health and Development Institute, Icahn School of Medicine at Mount Sinai; Black Family Stem Cell Institute, Icahn School of Medicine at Mount Sinai
| | - Nikos Tzavaras
- Microscopy Core, Icahn School of Medicine at Mount Sinai
| | - Deanna L Benson
- Department of Neuroscience, Icahn School of Medicine at Mount Sinai; Friedman Brain Institute, Icahn School of Medicine at Mount Sinai
| | - Nicole C Dubois
- Cell, Developmental, and Regenerative Biology Department, Icahn School of Medicine at Mount Sinai; Mindich Child Health and Development Institute, Icahn School of Medicine at Mount Sinai; Black Family Stem Cell Institute, Icahn School of Medicine at Mount Sinai;
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85
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Bessonnard S, Coqueran S, Vandormael-Pournin S, Dufour A, Artus J, Cohen-Tannoudji M. ICM conversion to epiblast by FGF/ERK inhibition is limited in time and requires transcription and protein degradation. Sci Rep 2017; 7:12285. [PMID: 28947813 PMCID: PMC5612930 DOI: 10.1038/s41598-017-12120-0] [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: 06/19/2017] [Accepted: 09/04/2017] [Indexed: 01/02/2023] Open
Abstract
Inner cell Mass (ICM) specification into epiblast (Epi) and primitive endoderm (PrE) is an asynchronous and progressive process taking place between E3.0 to E3.75 under the control of the Fibroblast Growth Factor (FGF)/Extracellular signal-Regulated Kinase (ERK) signaling pathway. Here, we have analyzed in details the kinetics of specification and found that ICM cell responsiveness to the up and down regulation of FGF signaling activity are temporally distinct. We also showed that PrE progenitors are generated later than Epi progenitors. We further demonstrated that, during this late phase of specification, a 4 hours period of FGF/ERK inhibition prior E3.75 is sufficient to convert ICM cells into Epi. Finally, we showed that ICM conversion into Epi in response to inhibition during this short time window requires both transcription and proteasome degradation. Collectively, our data give new insights into the timing and mechanisms involved in the process of ICM specification.
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Affiliation(s)
- Sylvain Bessonnard
- Institut Pasteur, CNRS, Unité de Génétique Fonctionnelle de la Souris, UMR 3738, Department of Developmental & Stem Cell Biology, 25 rue du docteur Roux, F-75015, Paris, France
| | - Sabrina Coqueran
- Institut Pasteur, CNRS, Unité de Génétique Fonctionnelle de la Souris, UMR 3738, Department of Developmental & Stem Cell Biology, 25 rue du docteur Roux, F-75015, Paris, France
| | - Sandrine Vandormael-Pournin
- Institut Pasteur, CNRS, Unité de Génétique Fonctionnelle de la Souris, UMR 3738, Department of Developmental & Stem Cell Biology, 25 rue du docteur Roux, F-75015, Paris, France
| | - Alexandre Dufour
- Institut Pasteur, Bioimage Analysis Unit, CNRS UMR 3691, Paris, France.,INSERM UMR935, Paul Brousse Hospital, University Paris Sud, Villejuif, France
| | - Jérôme Artus
- Institut Pasteur, CNRS, Unité de Génétique Fonctionnelle de la Souris, UMR 3738, Department of Developmental & Stem Cell Biology, 25 rue du docteur Roux, F-75015, Paris, France. .,INSERM UMR935, Paul Brousse Hospital, University Paris Sud, Villejuif, France. .,Faculty of Medicine, Kremlin-Bicêtre, University Paris Sud, Paris Saclay, France.
| | - Michel Cohen-Tannoudji
- Institut Pasteur, CNRS, Unité de Génétique Fonctionnelle de la Souris, UMR 3738, Department of Developmental & Stem Cell Biology, 25 rue du docteur Roux, F-75015, Paris, France.
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86
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Piliszek A, Madeja ZE, Plusa B. Suppression of ERK signalling abolishes primitive endoderm formation but does not promote pluripotency in rabbit embryo. Development 2017; 144:3719-3730. [PMID: 28935706 PMCID: PMC5675450 DOI: 10.1242/dev.156406] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2017] [Accepted: 09/04/2017] [Indexed: 12/13/2022]
Abstract
Formation of epiblast (EPI) – the founder line of all embryonic lineages – and extra-embryonic supportive tissues is one of the key events in mammalian development. The prevailing model of early mammalian development is based almost exclusively on the mouse. Here, we provide a comprehensive, stage-by-stage analysis of EPI and extra-embryonic primitive endoderm (PrE) formation during preimplantation development of the rabbit. Although we observed that rabbit embryos have several features in common with mouse embryos, including a stage-related initiation of lineage specification, our results demonstrate the existence of some key differences in lineage specification among mammals. Contrary to the current view, our data suggest that reciprocal repression of GATA6 and NANOG is not fundamental for the initial stages of PrE versus EPI specification in mammals. Furthermore, our results provide insight into the observed discrepancies relating to the role of FGF/ERK signalling in PrE versus EPI specification between mouse and other mammals. Highlighted Article: A comprehensive analysis of rabbit preimplantation development reveals key differences between rabbit and mouse, with some aspects of lineage specification in rabbit more closely resembling that of human and primate embryos.
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Affiliation(s)
- Anna Piliszek
- Department of Experimental Embryology, Institute of Genetics and Animal Breeding, Polish Academy of Sciences, Postępu 36a, 05-552 Jastrzębiec, Poland
| | - Zofia E Madeja
- Department of Genetics and Animal Breeding, Faculty of Veterinary Medicine and Animal Sciences, Poznan University of Life Sciences, Wołyńska 33, 60-637 Poznań, Poland
| | - Berenika Plusa
- Faculty of Biology, Medicine and Health, The University of Manchester, Oxford Road, Manchester M13 9PT, UK
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87
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Nissen SB, Perera M, Gonzalez JM, Morgani SM, Jensen MH, Sneppen K, Brickman JM, Trusina A. Four simple rules that are sufficient to generate the mammalian blastocyst. PLoS Biol 2017; 15:e2000737. [PMID: 28700688 PMCID: PMC5507476 DOI: 10.1371/journal.pbio.2000737] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2016] [Accepted: 06/09/2017] [Indexed: 11/18/2022] Open
Abstract
Early mammalian development is both highly regulative and self-organizing. It involves the interplay of cell position, predetermined gene regulatory networks, and environmental interactions to generate the physical arrangement of the blastocyst with precise timing. However, this process occurs in the absence of maternal information and in the presence of transcriptional stochasticity. How does the preimplantation embryo ensure robust, reproducible development in this context? It utilizes a versatile toolbox that includes complex intracellular networks coupled to cell-cell communication, segregation by differential adhesion, and apoptosis. Here, we ask whether a minimal set of developmental rules based on this toolbox is sufficient for successful blastocyst development, and to what extent these rules can explain mutant and experimental phenotypes. We implemented experimentally reported mechanisms for polarity, cell-cell signaling, adhesion, and apoptosis as a set of developmental rules in an agent-based in silico model of physically interacting cells. We find that this model quantitatively reproduces specific mutant phenotypes and provides an explanation for the emergence of heterogeneity without requiring any initial transcriptional variation. It also suggests that a fixed time point for the cells' competence of fibroblast growth factor (FGF)/extracellular signal-regulated kinase (ERK) sets an embryonic clock that enables certain scaling phenomena, a concept that we evaluate quantitatively by manipulating embryos in vitro. Based on these observations, we conclude that the minimal set of rules enables the embryo to experiment with stochastic gene expression and could provide the robustness necessary for the evolutionary diversification of the preimplantation gene regulatory network.
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Affiliation(s)
- Silas Boye Nissen
- StemPhys, Niels Bohr Institute, University of Copenhagen, Copenhagen, Denmark
| | - Marta Perera
- The Danish Stem Cell Centre, DanStem, University of Copenhagen, Copenhagen, Denmark
| | | | - Sophie M. Morgani
- The Danish Stem Cell Centre, DanStem, University of Copenhagen, Copenhagen, Denmark
| | - Mogens H. Jensen
- StemPhys, Niels Bohr Institute, University of Copenhagen, Copenhagen, Denmark
| | - Kim Sneppen
- CMOL, Niels Bohr Institute, University of Copenhagen, Copenhagen, Denmark
| | - Joshua M. Brickman
- StemPhys, Niels Bohr Institute, University of Copenhagen, Copenhagen, Denmark
- The Danish Stem Cell Centre, DanStem, University of Copenhagen, Copenhagen, Denmark
- * E-mail: (JMB); (AT)
| | - Ala Trusina
- StemPhys, Niels Bohr Institute, University of Copenhagen, Copenhagen, Denmark
- * E-mail: (JMB); (AT)
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88
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Morgani S, Nichols J, Hadjantonakis AK. The many faces of Pluripotency: in vitro adaptations of a continuum of in vivo states. BMC DEVELOPMENTAL BIOLOGY 2017; 17:7. [PMID: 28610558 PMCID: PMC5470286 DOI: 10.1186/s12861-017-0150-4] [Citation(s) in RCA: 108] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/28/2017] [Accepted: 06/01/2017] [Indexed: 12/20/2022]
Abstract
Pluripotency defines the propensity of a cell to differentiate into, and generate, all somatic, as well as germ cells. The epiblast of the early mammalian embryo is the founder population of all germ layer derivatives and thus represents the bona fide in vivo pluripotent cell population. The so-called pluripotent state spans several days of development and is lost during gastrulation as epiblast cells make fate decisions towards a mesoderm, endoderm or ectoderm identity. It is now widely recognized that the features of the pluripotent population evolve as development proceeds from the pre- to post-implantation period, marked by distinct transcriptional and epigenetic signatures. During this period of time epiblast cells mature through a continuum of pluripotent states with unique properties. Aspects of this pluripotent continuum can be captured in vitro in the form of stable pluripotent stem cell types. In this review we discuss the continuum of pluripotency existing within the mammalian embryo, using the mouse as a model, and the cognate stem cell types that can be derived and propagated in vitro. Furthermore, we speculate on embryonic stage-specific characteristics that could be utilized to identify novel, developmentally relevant, pluripotent states.
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Affiliation(s)
- Sophie Morgani
- Developmental Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA
- Wellcome Trust-Medical Research Council Centre for Stem Cell Research, University of Cambridge, Tennis Court Road, Cambridge, CB2 1QR, UK
| | - Jennifer Nichols
- Wellcome Trust-Medical Research Council Centre for Stem Cell Research, University of Cambridge, Tennis Court Road, Cambridge, CB2 1QR, UK
| | - Anna-Katerina Hadjantonakis
- Developmental Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA.
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89
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Abstract
Embryonic development is a self-organised process during which cells divide, interact, change fate according to a complex gene regulatory network and organise themselves in a three-dimensional space. Here, we model this complex dynamic phenomenon in the context of the acquisition of epiblast and primitive endoderm identities within the inner cell mass of the preimplantation embryo in the mouse. The multiscale model describes cell division and interactions between cells, as well as biochemical reactions inside each individual cell and in the extracellular matrix. The computational results first confirm that the previously proposed mechanism by which extra-cellular signalling allows cells to select the appropriate fate in a tristable regulatory network is robust when considering a realistic framework involving cell division and three-dimensional interactions. The simulations recapitulate a variety of in vivo observations on wild-type and mutant embryos and suggest that the gene regulatory network confers differential plasticity to the different cell fates. A detailed analysis of the specification process emphasizes that developmental transitions and the salt-and-pepper patterning of epiblast and primitive endoderm cells from a homogenous population of inner cell mass cells arise from the interplay between the internal gene regulatory network and extracellular signalling by Fgf4. Importantly, noise is necessary to create some initial heterogeneity in the specification process. The simulations suggest that initial cell-to-cell differences originating from slight inhomogeneities in extracellular Fgf4 signalling, in possible combination with slightly different concentrations of the key transcription factors between daughter cells, are able to break the original symmetry and are amplified in a flexible and self-regulated manner until the blastocyst stage.
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90
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Kang M, Garg V, Hadjantonakis AK. Lineage Establishment and Progression within the Inner Cell Mass of the Mouse Blastocyst Requires FGFR1 and FGFR2. Dev Cell 2017; 41:496-510.e5. [PMID: 28552559 DOI: 10.1016/j.devcel.2017.05.003] [Citation(s) in RCA: 100] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2016] [Revised: 04/17/2017] [Accepted: 04/30/2017] [Indexed: 11/29/2022]
Abstract
Fibroblast growth factor 4 (FGF4) is the key signal driving specification of primitive endoderm (PrE) versus pluripotent epiblast (EPI) within the inner cell mass (ICM) of the mouse blastocyst. To gain insight into the receptor(s) responding to FGF4 within ICM cells, we combined single-cell-resolution quantitative imaging with single-cell transcriptomics of wild-type and Fgf receptor (Fgfr) mutant embryos. Despite the PrE-specific expression of FGFR2, it is FGFR1, expressed by all ICM cells, that is critical for establishment of a PrE identity. Signaling through FGFR1 is also required to constrain levels of the pluripotency-associated factor NANOG in EPI cells. However, the activity of both receptors is required for lineage establishment within the ICM. Gene expression profiling of 534 single ICM cells identified distinct downstream targets associated with each receptor. These data lead us to propose a model whereby unique and additive activities of FGFR1 and FGFR2 within the ICM coordinate establishment of two distinct lineages.
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Affiliation(s)
- Minjung Kang
- Developmental Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA; Biochemistry Cell and Molecular Biology Program, Weill Cornell Graduate School of Medical Sciences, Cornell University, New York, NY 10065, USA
| | - Vidur Garg
- Developmental Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA; Biochemistry Cell and Molecular Biology Program, Weill Cornell Graduate School of Medical Sciences, Cornell University, New York, NY 10065, USA
| | - Anna-Katerina Hadjantonakis
- Developmental Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA.
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91
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Molotkov A, Mazot P, Brewer JR, Cinalli RM, Soriano P. Distinct Requirements for FGFR1 and FGFR2 in Primitive Endoderm Development and Exit from Pluripotency. Dev Cell 2017; 41:511-526.e4. [PMID: 28552557 DOI: 10.1016/j.devcel.2017.05.004] [Citation(s) in RCA: 114] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2016] [Revised: 03/13/2017] [Accepted: 04/30/2017] [Indexed: 12/23/2022]
Abstract
Activation of the FGF signaling pathway during preimplantation development of the mouse embryo is known to be essential for differentiation of the inner cell mass and the formation of the primitive endoderm (PrE). We now show using fluorescent reporter knockin lines that Fgfr1 is expressed in all cell populations of the blastocyst, while Fgfr2 expression becomes restricted to extraembryonic lineages, including the PrE. We further show that loss of both receptors prevents the development of the PrE and demonstrate that FGFR1 plays a more prominent role in this process than FGFR2. Finally, we document an essential role for FGFRs in embryonic stem cell (ESC) differentiation, with FGFR1 again having a greater influence than FGFR2 in ESC exit from the pluripotent state. Collectively, these results identify mechanisms through which FGF signaling regulates inner cell mass lineage restriction and cell commitment during preimplantation development.
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Affiliation(s)
- Andrei Molotkov
- Department of Cell, Developmental, and Regenerative Biology, Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Pierre Mazot
- Department of Cell, Developmental, and Regenerative Biology, Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - J Richard Brewer
- Department of Cell, Developmental, and Regenerative Biology, Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Ryan M Cinalli
- Department of Cell, Developmental, and Regenerative Biology, Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Philippe Soriano
- Department of Cell, Developmental, and Regenerative Biology, Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA.
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92
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Saiz N, Hadjantonakis AK. A developmental insurance policy. eLife 2017; 6. [PMID: 28350296 PMCID: PMC5370181 DOI: 10.7554/elife.26260] [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] [Received: 03/21/2017] [Accepted: 03/21/2017] [Indexed: 11/26/2022] Open
Abstract
Why does a totipotent state linger within the inner cell mass of mouse embryos?
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Affiliation(s)
- Nestor Saiz
- Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, United States
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93
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Azami T, Waku T, Matsumoto K, Jeon H, Muratani M, Kawashima A, Yanagisawa J, Manabe I, Nagai R, Kunath T, Nakamura T, Kurimoto K, Saitou M, Takahashi S, Ema M. Klf5 maintains the balance of primitive endoderm to epiblast specification during mouse embryonic development by suppression of Fgf4. Development 2017; 144:3706-3718. [DOI: 10.1242/dev.150755] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2017] [Accepted: 08/25/2017] [Indexed: 12/17/2022]
Abstract
The inner cell mass of the mouse blastocyst gives rise to the pluripotent epiblast (EPI), which forms the embryo proper, and the primitive endoderm (PrE), which forms extra-embryonic yolk sac tissues. All inner cells co-express lineage markers such as Nanog and Gata6 at embryonic day (E) 3.25, and the EPI and PrE precursor cells eventually segregate to exclusively express Nanog and Gata6, respectively. Fibroblast growth factor (FGF)/extracellular signal-regulated kinase (ERK) signalling is involved in segregation of the EPI and PrE lineages; however, the mechanism involved in Fgf4-regulation is poorly understood. Here, we identified Klf5 as an upstream repressor of Fgf4. While Fgf4 was markedly upregulated in Klf5 knockout (KO) embryos at E3.0, it was downregulated in embryos overexpressing Klf5. Furthermore, Klf5 KO and overexpressing blastocysts showed skewed lineage specification phenotypes, similar to FGF4-treated preimplantation embryos and Fgf4 KO embryos, respectively. Inhibitors of the FGF receptor and ERK pathways reversed the skewed lineage specification of Klf5 KO blastocysts. These data demonstrate that Klf5 suppresses Fgf4-Fgfr-ERK signalling, thus preventing precocious activation of the PrE specification programme.
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Affiliation(s)
- Takuya Azami
- Department of Anatomy and Embryology, Faculty of Medicine, University of Tsukuba, 1-1-1 Tennoudai, Tsukuba, Ibaraki 305-8575, Japan
- 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
| | - Tsuyoshi Waku
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Ken Matsumoto
- 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
| | - Hyojung Jeon
- Department of Anatomy and Embryology, Faculty of Medicine, University of Tsukuba, 1-1-1 Tennoudai, Tsukuba, Ibaraki 305-8575, Japan
| | - Masafumi Muratani
- Department of Genome Biology, Faculty of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8575, Japan
| | - Akihiro Kawashima
- Department of Anatomy and Embryology, Faculty of Medicine, University of Tsukuba, 1-1-1 Tennoudai, Tsukuba, Ibaraki 305-8575, Japan
| | - Jun Yanagisawa
- Graduate School of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8577, Japan
- Center for Tsukuba Advanced Research Alliance, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8577, Japan
| | - Ichiro Manabe
- Department of Cardiovascular Medicine, The University of Tokyo Graduate School of Medicine, Bunkyo, Tokyo 113-8655, Japan
| | - Ryozo Nagai
- Jichi Medical University, 3311-1 Yakushiji, Shimotsuke, Tochigi 329-0498, Japan
| | - Tilo Kunath
- MRC Centre for Regenerative Medicine, School of Biological Sciences, University of Edinburgh, 5 Little France Drive, Edinburgh EH16 4UU, UK
| | - Tomonori Nakamura
- Department of Anatomy and Cell Biology, Graduate School of Medicine, Kyoto University, Yoshida-Konoe-cho, Sakyo-ku, Kyoto 606-8501, Japan
- JST, ERATO, Yoshida-Konoe-cho, Sakyo-ku, Kyoto 606-8501, Japan
| | - Kazuki Kurimoto
- Department of Anatomy and Cell Biology, Graduate School of Medicine, Kyoto University, Yoshida-Konoe-cho, Sakyo-ku, Kyoto 606-8501, Japan
- JST, ERATO, Yoshida-Konoe-cho, Sakyo-ku, Kyoto 606-8501, Japan
| | - Mitinori Saitou
- Department of Anatomy and Cell Biology, Graduate School of Medicine, Kyoto University, Yoshida-Konoe-cho, Sakyo-ku, Kyoto 606-8501, Japan
- JST, ERATO, Yoshida-Konoe-cho, Sakyo-ku, Kyoto 606-8501, Japan
- Department of Reprogramming Science, Center for iPS Cell Research and Application, Kyoto University, 53 Kawahara-cho, Shogoin Yoshida, Sakyo-ku, Kyoto 606-8507, Japan
- Institute for Integrated Cell-Material Sciences, Kyoto University, Yoshida-Ushinomiya-cho, Sakyo-ku, Kyoto 606-8501, Japan
| | - Satoru Takahashi
- Department of Anatomy and Embryology, Faculty of Medicine, University of Tsukuba, 1-1-1 Tennoudai, Tsukuba, Ibaraki 305-8575, Japan
- Center for Tsukuba Advanced Research Alliance, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8577, Japan
- International Institute for Integrative Sleep Medicine, Life Science Center, and Laboratory Animal Resource Center, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8577, Japan
| | - 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
- PRESTO, Japan Science and Technology Agency, 4-1-8 Honcho Kawaguchi, Saitama 332-0012, Japan
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Asynchronous fate decisions by single cells collectively ensure consistent lineage composition in the mouse blastocyst. Nat Commun 2016; 7:13463. [PMID: 27857135 PMCID: PMC5120222 DOI: 10.1038/ncomms13463] [Citation(s) in RCA: 92] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2016] [Accepted: 10/04/2016] [Indexed: 01/18/2023] Open
Abstract
Intercellular communication is essential to coordinate the behaviour of individual cells during organismal development. The preimplantation mammalian embryo is a paradigm of tissue self-organization and regulative development; however, the cellular basis of these regulative abilities has not been established. Here we use a quantitative image analysis pipeline to undertake a high-resolution, single-cell level analysis of lineage specification in the inner cell mass (ICM) of the mouse blastocyst. We show that a consistent ratio of epiblast and primitive endoderm lineages is achieved through incremental allocation of cells from a common progenitor pool, and that the lineage composition of the ICM is conserved regardless of its size. Furthermore, timed modulation of the FGF-MAPK pathway shows that individual progenitors commit to either fate asynchronously during blastocyst development. These data indicate that such incremental lineage allocation provides the basis for a tissue size control mechanism that ensures the generation of lineages of appropriate size. Early embryonic cell fate and lineage specification is tightly regulated in the preimplantation mammalian embryo. Here, the authors quantitatively examine the ratio of epiblast to primitive endoderm lineages in the blastocyst and show composition of the inner cell mass is conserved, independent of its size.
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