1
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Skory RM. Revisiting trophectoderm-inner cell mass lineage segregation in the mammalian preimplantation embryo. Hum Reprod 2024; 39:1889-1898. [PMID: 38926157 DOI: 10.1093/humrep/deae142] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2024] [Revised: 06/06/2024] [Indexed: 06/28/2024] Open
Abstract
In the first days of life, cells of the mammalian embryo segregate into two distinct lineages, trophectoderm and inner cell mass. Unlike nonmammalian species, mammalian development does not proceed from predetermined factors in the oocyte. Rather, asymmetries arise de novo in the early embryo incorporating cues from cell position, contractility, polarity, and cell-cell contacts. Molecular heterogeneities, including transcripts and non-coding RNAs, have now been characterized as early as the 2-cell stage. However, it's debated whether these early heterogeneities bias cells toward one fate or the other or whether lineage identity arises stochastically at the 16-cell stage. This review summarizes what is known about early blastomere asymmetries and our understanding of lineage allocation in the context of historical models. Preimplantation development is reviewed coupled with what is known about changes in morphology, contractility, and transcription factor networks. The addition of single-cell atlases of human embryos has begun to reveal key differences between human and mouse, including the timing of events and core transcription factors. Furthermore, the recent generation of blastoid models will provide valuable tools to test and understand fate determinants. Lastly, new techniques are reviewed, which may better synthesize existing knowledge with emerging data sets and reconcile models with the regulative capacity unique to the mammalian embryo.
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Affiliation(s)
- Robin M Skory
- Division of Reproductive Endocrinology and Infertility, Department of Obstetrics and Gynecology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Department of Cell and Developmental Biology, Institute for Regenerative Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
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2
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Zhang Y, Li X, Gao S, Liao Y, Luo Y, Liu M, Bian Y, Xiong H, Yue Y, He A. Genetic reporter for live tracing fluid flow forces during cell fate segregation in mouse blastocyst development. Cell Stem Cell 2023; 30:1110-1123.e9. [PMID: 37541214 DOI: 10.1016/j.stem.2023.07.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2023] [Revised: 06/02/2023] [Accepted: 07/10/2023] [Indexed: 08/06/2023]
Abstract
Mechanical forces are known to be important in mammalian blastocyst formation; however, due to limited tools, specific force inputs and how they relay to first cell fate control of inner cell mass (ICM) and/or trophectoderm (TE) remain elusive. Combining in toto live imaging and various perturbation experiments, we demonstrate and measure fluid flow forces existing in the mouse blastocyst cavity and identify Klf2(Krüppel-like factor 2) as a fluid force reporter with force-responsive enhancers. Long-term live imaging and lineage reconstructions reveal that blastomeres subject to higher fluid flow forces adopt ICM cell fates. These are reinforced by internal ferrofluid-induced flow force assays. We also utilize ex vivo fluid flow force mimicking and pharmacological perturbations to confirm mechanosensing specificity. Together, we report a genetically encoded reporter for continuously monitoring fluid flow forces and cell fate decisions and provide a live imaging framework to infer force information enriched lineage landscape during development. VIDEO ABSTRACT.
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Affiliation(s)
- Youdong Zhang
- Institute of Molecular Medicine, National Biomedical Imaging Center, College of Future Technology, Peking-Tsinghua Center for Life Sciences, Peking University, Beijing 100871, China
| | - Xin Li
- Institute of Molecular Medicine, National Biomedical Imaging Center, College of Future Technology, Peking-Tsinghua Center for Life Sciences, Peking University, Beijing 100871, China
| | - Shu Gao
- Institute of Molecular Medicine, National Biomedical Imaging Center, College of Future Technology, Peking-Tsinghua Center for Life Sciences, Peking University, Beijing 100871, China
| | - Yuanhui Liao
- School of Software and Microelectronics, Peking University, Beijing 100871, China
| | - Yingjie Luo
- Institute of Molecular Medicine, National Biomedical Imaging Center, College of Future Technology, Peking-Tsinghua Center for Life Sciences, Peking University, Beijing 100871, China
| | - Min Liu
- Institute of Molecular Medicine, National Biomedical Imaging Center, College of Future Technology, Peking-Tsinghua Center for Life Sciences, Peking University, Beijing 100871, China
| | - Yunkun Bian
- Institute of Molecular Medicine, National Biomedical Imaging Center, College of Future Technology, Peking-Tsinghua Center for Life Sciences, Peking University, Beijing 100871, China
| | - Haiqing Xiong
- Institute of Molecular Medicine, National Biomedical Imaging Center, College of Future Technology, Peking-Tsinghua Center for Life Sciences, Peking University, Beijing 100871, China
| | - Yanzhu Yue
- Institute of Molecular Medicine, National Biomedical Imaging Center, College of Future Technology, Peking-Tsinghua Center for Life Sciences, Peking University, Beijing 100871, China; Department of Cell Fate and Diseases, Jilin Provincial Key Laboratory of Women's Reproductive Health, the First Hospital of Jilin University, Changchun, Jilin 130061, China.
| | - Aibin He
- Institute of Molecular Medicine, National Biomedical Imaging Center, College of Future Technology, Peking-Tsinghua Center for Life Sciences, Peking University, Beijing 100871, China.
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3
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Otsuka T, Shimojo H, Sasaki H. Daughter cells inherit YAP localization from mother cells in early preimplantation embryos. Dev Growth Differ 2023; 65:360-369. [PMID: 37309238 DOI: 10.1111/dgd.12870] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2023] [Revised: 05/30/2023] [Accepted: 06/08/2023] [Indexed: 06/14/2023]
Abstract
The first stage of cell differentiation during mouse development is the differentiation into the trophectoderm and inner cell mass, which occurs during the 8-32-cell stages of preimplantation embryos. This differentiation is regulated by the Hippo signaling pathway. At the 32-cell stage, embryos establish a position-dependent distribution of the Hippo pathway coactivator, Yes-associated protein 1 (YAP, encoded by Yap1). The outer and inner cells showed nuclear and cytoplasmic localization of YAP, respectively. However, the process by which embryos establish position-dependent YAP localization remains elusive. Here, we established a YAP-reporter mouse line, Yap1mScarlet , and examined YAP-mScarlet protein dynamics during the 8-32-cell stages using live imaging. During mitosis, YAP-mScarlet diffused throughout the cells. YAP-mScarlet dynamics in daughter cells varied depending on the cell division patterns. YAP-mScarlet localization in daughter cells at the completion of cell division coincided with that in mother cells. Experimental manipulation of YAP-mScarlet localization in mother cells also altered its localization in daughter cells upon completion of cell division. In daughter cells, YAP-mScarlet localization gradually changed to the final pattern. In some divisions during the 8-16-cell stages, the cytoplasmic YAP-mScarlet localization preceded cell internalization. These results suggest that cell position is not a primary determinant of YAP localization and that the Hippo signaling status of the mother cell is inherited by the daughter cells, which likely contributes to the stabilization of the cell fate specification process beyond cell division.
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Affiliation(s)
- Tomoaki Otsuka
- Laboratory for Embryogenesis, Graduate School of Frontier Biosciences, Osaka University, Osaka, Japan
| | - Hiromi Shimojo
- Laboratory for Embryogenesis, Graduate School of Frontier Biosciences, Osaka University, Osaka, Japan
| | - Hiroshi Sasaki
- Laboratory for Embryogenesis, Graduate School of Frontier Biosciences, Osaka University, Osaka, Japan
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4
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Nunley H, Shao B, Grover P, Singh J, Joyce B, Kim-Yip R, Kohrman A, Watters A, Gal Z, Kickuth A, Chalifoux M, Shvartsman S, Posfai E, Brown LM. A novel ground truth dataset enables robust 3D nuclear instance segmentation in early mouse embryos. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.03.14.532646. [PMID: 36993260 PMCID: PMC10055179 DOI: 10.1101/2023.03.14.532646] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/19/2023]
Abstract
For investigations into fate specification and cell rearrangements in live images of preimplantation embryos, automated and accurate 3D instance segmentation of nuclei is invaluable; however, the performance of segmentation methods is limited by the images' low signal-to-noise ratio and high voxel anisotropy and the nuclei's dense packing and variable shapes. Supervised machine learning approaches have the potential to radically improve segmentation accuracy but are hampered by a lack of fully annotated 3D data. In this work, we first establish a novel mouse line expressing near-infrared nuclear reporter H2B-miRFP720. H2B-miRFP720 is the longest wavelength nuclear reporter in mice and can be imaged simultaneously with other reporters with minimal overlap. We then generate a dataset, which we call BlastoSPIM, of 3D microscopy images of H2B-miRFP720-expressing embryos with ground truth for nuclear instance segmentation. Using BlastoSPIM, we benchmark the performance of five convolutional neural networks and identify Stardist-3D as the most accurate instance segmentation method across preimplantation development. Stardist-3D, trained on BlastoSPIM, performs robustly up to the end of preimplantation development (> 100 nuclei) and enables studies of fate patterning in the late blastocyst. We, then, demonstrate BlastoSPIM's usefulness as pre-train data for related problems. BlastoSPIM and its corresponding Stardist-3D models are available at: blastospim.flatironinstitute.org.
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Affiliation(s)
- Hayden Nunley
- Center for Computational Biology, Flatiron Institute - Simons Foundation, New York, United States of America
| | - Binglun Shao
- Center for Computational Biology, Flatiron Institute - Simons Foundation, New York, United States of America
- Department of Chemical and Biological Engineering, Princeton University, Princeton, New Jersey, United States of America
| | - Prateek Grover
- Center for Computational Biology, Flatiron Institute - Simons Foundation, New York, United States of America
| | - Jaspreet Singh
- Center for Computational Biology, Flatiron Institute - Simons Foundation, New York, United States of America
| | - Bradley Joyce
- Department of Molecular Biology, Princeton University, Princeton, New Jersey, United States of America
| | - Rebecca Kim-Yip
- Department of Molecular Biology, Princeton University, Princeton, New Jersey, United States of America
| | - Abraham Kohrman
- Department of Molecular Biology, Princeton University, Princeton, New Jersey, United States of America
| | - Aaron Watters
- Center for Computational Biology, Flatiron Institute - Simons Foundation, New York, United States of America
| | - Zsombor Gal
- Department of Molecular Biology, Princeton University, Princeton, New Jersey, United States of America
| | - Alison Kickuth
- Department of Molecular Biology, Princeton University, Princeton, New Jersey, United States of America
| | - Madeleine Chalifoux
- Department of Chemical and Biological Engineering, Princeton University, Princeton, New Jersey, United States of America
- Department of Molecular Biology, Princeton University, Princeton, New Jersey, United States of America
| | - Stanislav Shvartsman
- Center for Computational Biology, Flatiron Institute - Simons Foundation, New York, United States of America
- Department of Chemical and Biological Engineering, Princeton University, Princeton, New Jersey, United States of America
- Department of Molecular Biology, Princeton University, Princeton, New Jersey, United States of America
- The Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, New Jersey, United States of America
| | - Eszter Posfai
- Department of Molecular Biology, Princeton University, Princeton, New Jersey, United States of America
| | - Lisa M. Brown
- Center for Computational Biology, Flatiron Institute - Simons Foundation, New York, United States of America
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5
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Handschuh S, Glösmann M. Mouse embryo phenotyping using X-ray microCT. Front Cell Dev Biol 2022; 10:949184. [PMID: 36187491 PMCID: PMC9523164 DOI: 10.3389/fcell.2022.949184] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2022] [Accepted: 08/22/2022] [Indexed: 11/30/2022] Open
Abstract
Microscopic X-ray computed tomography (microCT) is a structural ex vivo imaging technique providing genuine isotropic 3D images from biological samples at micron resolution. MicroCT imaging is non-destructive and combines well with other modalities such as light and electron microscopy in correlative imaging workflows. Protocols for staining embryos with X-ray dense contrast agents enable the acquisition of high-contrast and high-resolution datasets of whole embryos and specific organ systems. High sample throughput is achieved with dedicated setups. Consequently, microCT has gained enormous importance for both qualitative and quantitative phenotyping of mouse development. We here summarize state-of-the-art protocols of sample preparation and imaging procedures, showcase contemporary applications, and discuss possible pitfalls and sources for artefacts. In addition, we give an outlook on phenotyping workflows using microscopic dual energy CT (microDECT) and tissue-specific contrast agents.
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6
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Rouillon J, Ali LMA, Hadj-Kaddour K, Marie-Luce R, Simon G, Onofre M, Denis-Quanquin S, Jean M, Albalat M, Vanthuyne N, Micouin G, Banyasz A, Gary-Bobo M, Monnereau C, Andraud C. Assembly of Aggregation-Induced Emission Active Bola-Amphiphilic Macromolecules into Luminescent Nanoparticles Optimized for Two-Photon Microscopy In Vivo. Biomacromolecules 2022; 23:2485-2495. [PMID: 35608946 DOI: 10.1021/acs.biomac.2c00232] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The (Z) and (E)-isomers of an extended tetraphenylethylene-based chromophore with optimized two-photon-induced luminescence properties are separated and functionalized with water-solubilizing pendant polymer groups, promoting their self-assembly in physiological media in the form of small, colloidal stable organic nanoparticles. The two resulting fluorescent suspensions are then evaluated as potential two-photon luminescent contrast agents for intravital epifluorescence and two-photon fluorescence microscopy. Comparisons with previously reported works involving similar fluorophores devoid of polymer side chains illustrate the benefits of later functionalization regarding the control of the self-assembly of the nano-objects and ultimately their biocompatibility toward the imaged organism.
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Affiliation(s)
- Jean Rouillon
- Univ. Lyon, ENS Lyon, CNRS, Laboratoire de Chimie, UMR 5182, 46 Allée d'Italie, 69364 Lyon, France
| | - Lamiaa M A Ali
- IBMM, Univ. Montpellier, CNRS, ENSCM, Montpellier 34293, France.,Department of Biochemistry Medical Research Institute, University of Alexandria, 21561 Alexandria, Egypt
| | | | - Raphaël Marie-Luce
- Univ. Lyon, ENS Lyon, CNRS, Laboratoire de Chimie, UMR 5182, 46 Allée d'Italie, 69364 Lyon, France
| | - Guillaume Simon
- Univ. Lyon, ENS Lyon, CNRS, Laboratoire de Chimie, UMR 5182, 46 Allée d'Italie, 69364 Lyon, France
| | - Mélanie Onofre
- IBMM, Univ. Montpellier, CNRS, ENSCM, Montpellier 34293, France
| | - Sandrine Denis-Quanquin
- Univ. Lyon, ENS Lyon, CNRS, Laboratoire de Chimie, UMR 5182, 46 Allée d'Italie, 69364 Lyon, France
| | - Marion Jean
- Aix Marseille University, CNRS, Centrale Marseille, iSm2, Marseille 13284, France
| | - Muriel Albalat
- Aix Marseille University, CNRS, Centrale Marseille, iSm2, Marseille 13284, France
| | - Nicolas Vanthuyne
- Aix Marseille University, CNRS, Centrale Marseille, iSm2, Marseille 13284, France
| | - Guillaume Micouin
- Univ. Lyon, ENS Lyon, CNRS, Laboratoire de Chimie, UMR 5182, 46 Allée d'Italie, 69364 Lyon, France
| | - Akos Banyasz
- Univ. Lyon, ENS Lyon, CNRS, Laboratoire de Chimie, UMR 5182, 46 Allée d'Italie, 69364 Lyon, France
| | | | - Cyrille Monnereau
- Univ. Lyon, ENS Lyon, CNRS, Laboratoire de Chimie, UMR 5182, 46 Allée d'Italie, 69364 Lyon, France
| | - Chantal Andraud
- Univ. Lyon, ENS Lyon, CNRS, Laboratoire de Chimie, UMR 5182, 46 Allée d'Italie, 69364 Lyon, France
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7
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Thowfeequ S, Stower MJ, Srinivas S. Epithelial dynamics during early mouse development. Curr Opin Genet Dev 2022; 72:110-117. [PMID: 34929609 PMCID: PMC7615355 DOI: 10.1016/j.gde.2021.11.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2021] [Revised: 11/19/2021] [Accepted: 11/23/2021] [Indexed: 11/03/2022]
Abstract
The first epithelia to arise in an organism face the challenge of maintaining the integrity of the newly formed tissue, while exhibiting the behavioral flexibility required for morphogenetic processes to occur effectively. Epithelial cells integrate biochemical and biomechanical cues, both intrinsic and extrinsic, in order to bring about the molecular changes which determine their morphology, behavior and fate. In this review we highlight recent advances in our understanding of the various dynamic processes that the emergent epithelial cells undergo during the first seven days of mouse development and speculate what the future holds in understanding the mechanistic bases for these processes through integrative approaches.
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Affiliation(s)
- Shifaan Thowfeequ
- University of Oxford, Department of Physiology, Anatomy and Genetics, South Parks Road, Oxford, OX1 3QX, UK
| | - Matthew J Stower
- University of Oxford, Department of Physiology, Anatomy and Genetics, South Parks Road, Oxford, OX1 3QX, UK
| | - Shankar Srinivas
- University of Oxford, Department of Physiology, Anatomy and Genetics, South Parks Road, Oxford, OX1 3QX, UK.
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8
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Cell fate determination and Hippo signaling pathway in preimplantation mouse embryo. Cell Tissue Res 2021; 386:423-444. [PMID: 34586506 DOI: 10.1007/s00441-021-03530-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Accepted: 09/20/2021] [Indexed: 10/20/2022]
Abstract
First cell fate determination plays crucial roles in cell specification during early phases of embryonic development. Three classical concepts have been proposed to explain the lineage specification mechanism of the preimplantation embryo: inside-outside, pre-patterning, and polarity models. Transcriptional effectors of the Hippo signal pathway are YAP and TAZ activators that can create a shuttle between the cytoplasm and the nucleus. Despite different localizations of YAP in the cell, it determines the fate of ICM and TE. How the decisive cue driving factors that determine YAP localization are coordinated remains a central unanswered question. How can an embryonic cell find its position? The objective of this review is to summarize the molecular and mechanical aspects in cell fate decision during mouse preimplantation embryonic development. The findings will reveal the relationship between cell-cell adhesion, cell polarity, and determination of cell fate during early embryonic development in mice and elucidate the inducing/inhibiting mechanisms that are involved in cell specification following zygotic genome activation and compaction processes. With future studies, new biophysical and chemical cues in the cell fate determination will impart significant spatiotemporal effects on early embryonic development. The achieved knowledge will provide important information to the development of new approaches to be used in infertility treatment and increase the success of pregnancy.
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9
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Abstract
The cytoskeleton - comprising actin filaments, microtubules and intermediate filaments - serves instructive roles in regulating cell function and behaviour during development. However, a key challenge in cell and developmental biology is to dissect how these different structures function and interact in vivo to build complex tissues, with the ultimate aim to understand these processes in a mammalian organism. The preimplantation mouse embryo has emerged as a primary model system for tackling this challenge. Not only does the mouse embryo share many morphological similarities with the human embryo during its initial stages of life, it also permits the combination of genetic manipulations with live-imaging approaches to study cytoskeletal dynamics directly within an intact embryonic system. These advantages have led to the discovery of novel cytoskeletal structures and mechanisms controlling lineage specification, cell-cell communication and the establishment of the first forms of tissue architecture during development. Here we highlight the diverse organization and functions of each of the three cytoskeletal filaments during the key events that shape the early mammalian embryo, and discuss how they work together to perform key developmental tasks, including cell fate specification and morphogenesis of the blastocyst. Collectively, these findings are unveiling a new picture of how cells in the early embryo dynamically remodel their cytoskeleton with unique spatial and temporal precision to drive developmental processes in the rapidly changing in vivo environment.
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10
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Kaneshiro J, Shioi G, Okamoto K, Onami S, Watanabe TM. Improvement in image quality via the pseudo confocal effect in multidirectional digital scanned laser light-sheet microscopy. OPTICS EXPRESS 2021; 29:24278-24288. [PMID: 34614676 DOI: 10.1364/oe.423783] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/19/2021] [Accepted: 06/21/2021] [Indexed: 06/13/2023]
Abstract
Multidirectional digital scanned laser light-sheet microscopy (mDSLM) cannot be used with the current pseudo confocal system to reduce blurring and background signals. The multiline scanning for light-sheet illumination and the simple image construction proposed in this study are alternative to the pseudo confocal system. We investigate the effectiveness of our pseudo confocal method combined with mDSLM on artificial phantoms and biological samples. The results indicate that image quality from mDSLM can be improved by the confocal effect; their combination is effective and can be applied to biological investigations.
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11
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O'Hagan D, Kruger RE, Gu B, Ralston A. Efficient generation of endogenous protein reporters for mouse development. Development 2021; 148:269311. [PMID: 34036333 PMCID: PMC8276983 DOI: 10.1242/dev.197418] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2020] [Accepted: 05/20/2021] [Indexed: 01/09/2023]
Abstract
Fluorescent proteins and epitope tags can reveal protein localization in cells and animals, yet the large size of many tags hinders efficient genome targeting. Accordingly, many studies have relied on characterizing overexpressed proteins, which might not recapitulate endogenous protein activities. Here, we present two strategies for higher throughput production of endogenous protein reporters in mice, focusing on the blastocyst model of development. Our first strategy makes use of a split fluorescent protein, mNeonGreen2 (mNG2). Knock-in of a small portion of the mNG2 gene, in frame with gene coding regions of interest, was highly efficient in embryos, potentially obviating the need to establish mouse lines. When complemented by the larger portion of the mNG2 gene, fluorescence was reconstituted and endogenous protein localization faithfully reported in living embryos. Our second strategy achieves in-frame knock-in of a relatively small protein tag, which provides high efficiency and higher sensitivity protein reporting. Together, these two approaches provide complementary advantages and enable broad downstream applications.
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Affiliation(s)
- Daniel O'Hagan
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI 48824, USA
| | - Robin E Kruger
- Reproductive and Developmental Sciences Training Program, Michigan State University, East Lansing, MI 48824, USA
| | - Bin Gu
- Department of Obstetrics, Gynecology and Reproductive Biology, Michigan State University, East Lansing, MI 48824, USA.,Institute for Quantitative Health Science and Engineering, 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 Sciences Training Program, Michigan State University, East Lansing, MI 48824, USA
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12
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Liebisch T, Drusko A, Mathew B, Stelzer EHK, Fischer SC, Matthäus F. Cell fate clusters in ICM organoids arise from cell fate heredity and division: a modelling approach. Sci Rep 2020; 10:22405. [PMID: 33376253 PMCID: PMC7772343 DOI: 10.1038/s41598-020-80141-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2020] [Accepted: 12/17/2020] [Indexed: 01/13/2023] Open
Abstract
During the mammalian preimplantation phase, cells undergo two subsequent cell fate decisions. During the first decision, the trophectoderm and the inner cell mass are formed. Subsequently, the inner cell mass segregates into the epiblast and the primitive endoderm. Inner cell mass organoids represent an experimental model system, mimicking the second cell fate decision. It has been shown that cells of the same fate tend to cluster stronger than expected for random cell fate decisions. Three major processes are hypothesised to contribute to the cell fate arrangements: (1) chemical signalling; (2) cell sorting; and (3) cell proliferation. In order to quantify the influence of cell proliferation on the observed cell lineage type clustering, we developed an agent-based model accounting for mechanical cell-cell interaction, i.e. adhesion and repulsion, cell division, stochastic cell fate decision and cell fate heredity. The model supports the hypothesis that initial cell fate acquisition is a stochastically driven process, taking place in the early development of inner cell mass organoids. Further, we show that the observed neighbourhood structures can emerge solely due to cell fate heredity during cell division.
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Affiliation(s)
- Tim Liebisch
- Faculty of Biological Sciences and Frankfurt Institute for Advanced Studies (FIAS), Goethe Universität Frankfurt am Main, Ruth-Moufang-Straße 1, 60438, Frankfurt, Germany.
| | - Armin Drusko
- Faculty of Biological Sciences and Frankfurt Institute for Advanced Studies (FIAS), Goethe Universität Frankfurt am Main, Ruth-Moufang-Straße 1, 60438, Frankfurt, Germany
| | - Biena Mathew
- Faculty of Biological Sciences and Buchmann Institute for Molecular Life Sciences (BMLS), Goethe Universität Frankfurt am Main, Max-von-Laue Str. 15, 60438, Frankfurt, Germany
| | - Ernst H K Stelzer
- Faculty of Biological Sciences and Buchmann Institute for Molecular Life Sciences (BMLS), Goethe Universität Frankfurt am Main, Max-von-Laue Str. 15, 60438, Frankfurt, Germany
| | - Sabine C Fischer
- Center for Computational and Theoretical Biology (CCTB), Julius-Maximilians-Universität Würzburg, Campus Hubland Nord 32, 97074, Würzburg, Germany
| | - Franziska Matthäus
- Faculty of Biological Sciences and Frankfurt Institute for Advanced Studies (FIAS), Goethe Universität Frankfurt am Main, Ruth-Moufang-Straße 1, 60438, Frankfurt, Germany
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13
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Saiz N, Hadjantonakis AK. Coordination between patterning and morphogenesis ensures robustness during mouse development. Philos Trans R Soc Lond B Biol Sci 2020; 375:20190562. [PMID: 32829684 PMCID: PMC7482220 DOI: 10.1098/rstb.2019.0562] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/01/2020] [Indexed: 12/11/2022] Open
Abstract
The mammalian preimplantation embryo is a highly tractable, self-organizing developmental system in which three cell types are consistently specified without the need for maternal factors or external signals. Studies in the mouse over the past decades have greatly improved our understanding of the cues that trigger symmetry breaking in the embryo, the transcription factors that control lineage specification and commitment, and the mechanical forces that drive morphogenesis and inform cell fate decisions. These studies have also uncovered how these multiple inputs are integrated to allocate the right number of cells to each lineage despite inherent biological noise, and as a response to perturbations. In this review, we summarize our current understanding of how these processes are coordinated to ensure a robust and precise developmental outcome during early mouse development. This article is part of a discussion meeting issue 'Contemporary morphogenesis'.
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Affiliation(s)
- Néstor Saiz
- Developmental Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, NY 10065, USA
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14
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Toyooka Y. Trophoblast lineage specification in the mammalian preimplantation embryo. Reprod Med Biol 2020; 19:209-221. [PMID: 32684820 PMCID: PMC7360972 DOI: 10.1002/rmb2.12333] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2020] [Revised: 05/31/2020] [Accepted: 06/02/2020] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND The establishment of the trophectoderm (TE) and the inner cell mass (ICM) is the first cell lineage segregation that occurs in mammalian preimplantation development. TE will contribute to the placenta while ICM cells give rise to the epiblast (EPI) and primitive endoderm (PrE). There are two historical models for TE/ICM segregation: the positional (inside-outside) model and the polarity model, but both models alone cannot explain the mechanism of TE/ICM segregation. METHODS This article discusses a current possible model based on recent studies including the finding through live-cell imaging of the expression patterns of caudal type homeobox 2 (Cdx2), a key transcription factor of TE differentiation in the mouse embryo. RESULTS It was observed that a part of outer Cdx2-expressing blastomeres was internalized at the around 20- to 30-cell stage, downregulates Cdx2, ceases TE differentiation, and participates in ICM lineages. CONCLUSION The early blastomere, which starts differentiation toward the TE cell fate, still has plasticity and can change its fate. Differentiation potency of all blastomeres until approximately the 32-cell stage is presumably not irreversibly restricted even if they show heterogeneity in their epigenetic modifications or gene expression patterns.
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Affiliation(s)
- Yayoi Toyooka
- Center for iPS Cell Research and Application (CiRA)Kyoto UniversityKyotoJapan
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15
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Abstract
Embryonic development is highly complex and dynamic, requiring the coordination of numerous molecular and cellular events at precise times and places. Advances in imaging technology have made it possible to follow developmental processes at cellular, tissue, and organ levels over time as they take place in the intact embryo. Parallel innovations of in vivo probes permit imaging to report on molecular, physiological, and anatomical events of embryogenesis, but the resulting multidimensional data sets pose significant challenges for extracting knowledge. In this review, we discuss recent and emerging advances in imaging technologies, in vivo labeling, and data processing that offer the greatest potential for jointly deciphering the intricate cellular dynamics and the underlying molecular mechanisms. Our discussion of the emerging area of “image-omics” highlights both the challenges of data analysis and the promise of more fully embracing computation and data science for rapidly advancing our understanding of biology.
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Affiliation(s)
- Francesco Cutrale
- Department of Biomedical Engineering, University of Southern California, Los Angeles, California 90089, USA
- Translational Imaging Center, University of Southern California, Los Angeles, California 90089, USA
| | - Scott E. Fraser
- Department of Biomedical Engineering, University of Southern California, Los Angeles, California 90089, USA
- Translational Imaging Center, University of Southern California, Los Angeles, California 90089, USA
- Division of Molecular and Computational Biology, Department of Biological Sciences, University of Southern California, Los Angeles, California 90089, USA
| | - Le A. Trinh
- Translational Imaging Center, University of Southern California, Los Angeles, California 90089, USA
- Division of Molecular and Computational Biology, Department of Biological Sciences, University of Southern California, Los Angeles, California 90089, USA
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16
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Frum T, Ralston A. Visualizing HIPPO Signaling Components in Mouse Early Embryonic Development. Methods Mol Biol 2019; 1893:335-352. [PMID: 30565145 DOI: 10.1007/978-1-4939-8910-2_25] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The HIPPO signaling pathway plays an early and essential role in mammalian embryogenesis. The earliest known roles for HIPPO signaling during mouse development include segregating fetal and extraembryonic lineages and establishing the pluripotent progenitors of embryonic stem (ES) cells. In the mouse early embryo, HIPPO signaling responds to multiple cell biological inputs, including cell polarization, cytoskeleton, and cell environment, to influence gene expression and the first cell fate decisions in development. Methods to monitor and manipulate HIPPO signaling in the mouse early embryo are fundamental to discovering mechanisms regulating pluripotency in vivo, but properties of the early embryo, such as small cell number and spherical architecture, pose unique challenges for signaling pathway analysis. Here, we share approaches for visualizing HIPPO signaling in mouse early embryos. In addition, these methods can be applied to visualize HIPPO signaling in other spherical or cystic structures comprised of relatively few cells, such as organoids, or for the examination of other signaling pathways in these contexts.
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Affiliation(s)
- Tristan Frum
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI, USA
| | - Amy Ralston
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI, USA.
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17
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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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18
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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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19
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Our First Choice: Cellular and Genetic Underpinnings of Trophectoderm Identity and Differentiation in the Mammalian Embryo. Curr Top Dev Biol 2018; 128:59-80. [DOI: 10.1016/bs.ctdb.2017.10.009] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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20
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Cell Polarity-Dependent Regulation of Cell Allocation and the First Lineage Specification in the Preimplantation Mouse Embryo. Curr Top Dev Biol 2018; 128:11-35. [DOI: 10.1016/bs.ctdb.2017.10.008] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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21
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Bissiere S, Gasnier M, Alvarez YD, Plachta N. Cell Fate Decisions During Preimplantation Mammalian Development. Curr Top Dev Biol 2017; 128:37-58. [PMID: 29477170 DOI: 10.1016/bs.ctdb.2017.11.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
The early mouse embryo offers a phenomenal system to dissect how changes in the mechanisms controlling cell fate are integrated with morphogenetic events at the single-cell level. New technologies based on live imaging have enabled the discovery of dynamic changes in the regulation of single genes, transcription factors, and epigenetic mechanisms directing early cell fate decision in the early embryo. Here, we review recent progress in linking molecular dynamic events occurring at the level of the single cell in vivo, to some of the key morphogenetic changes regulating early mouse development.
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Affiliation(s)
| | - Maxime Gasnier
- Institute of Molecular and Cell Biology, A*STAR, Singapore, Singapore
| | - Yanina D Alvarez
- Institute of Molecular and Cell Biology, A*STAR, Singapore, Singapore; Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Conicet, Buenos Aires, Argentina
| | - Nicolas Plachta
- Institute of Molecular and Cell Biology, A*STAR, Singapore, Singapore; National University of Singapore, Singapore, Singapore.
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22
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Korotkevich E, Niwayama R, Courtois A, Friese S, Berger N, Buchholz F, Hiiragi T. The Apical Domain Is Required and Sufficient for the First Lineage Segregation in the Mouse Embryo. Dev Cell 2017; 40:235-247.e7. [PMID: 28171747 PMCID: PMC5300053 DOI: 10.1016/j.devcel.2017.01.006] [Citation(s) in RCA: 139] [Impact Index Per Article: 19.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2016] [Revised: 12/10/2016] [Accepted: 01/09/2017] [Indexed: 11/29/2022]
Abstract
Mammalian development begins with segregation of the extra-embryonic trophectoderm from the embryonic lineage in the blastocyst. While cell polarity and adhesion play key roles, the decisive cue driving this lineage segregation remains elusive. Here, to study symmetry breaking, we use a reduced system in which isolated blastomeres recapitulate the first lineage segregation. We find that in the 8-cell stage embryo, the apical domain recruits a spindle pole to ensure its differential distribution upon division. Daughter cells that inherit the apical domain adopt trophectoderm fate. However, the fate of apolar daughter cells depends on whether their position within the embryo facilitates apical domain formation by Cdh1-independent cell contact. Finally, we develop methods for transplanting apical domains and show that acquisition of this domain is not only required but also sufficient for the first lineage segregation. Thus, we provide mechanistic understanding that reconciles previous models for symmetry breaking in mouse development. A reduced system was established to study symmetry breaking in mouse development 8-cell stage blastomeres acquire the capacity to self-organize the apical domain The apical domain is required and sufficient for the first lineage segregation Contact asymmetry specifies cell fate, leading to self-organized embryo patterning
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Affiliation(s)
- Ekaterina Korotkevich
- Developmental Biology Unit, European Molecular Biology Laboratory (EMBL), 69117 Heidelberg, Germany
| | - Ritsuya Niwayama
- Developmental Biology Unit, European Molecular Biology Laboratory (EMBL), 69117 Heidelberg, Germany
| | - Aurélien Courtois
- Developmental Biology Unit, European Molecular Biology Laboratory (EMBL), 69117 Heidelberg, Germany
| | - Stefanie Friese
- Developmental Biology Unit, European Molecular Biology Laboratory (EMBL), 69117 Heidelberg, Germany
| | - Nicolas Berger
- Medical Systems Biology, UCC, University Hospital and Medical Faculty Carl Gustav Carus, TU Dresden, 01062 Dresden, Germany; Max Planck Institute of Molecular Cell Biology and Genetics, 01307 Dresden, Germany
| | - Frank Buchholz
- Medical Systems Biology, UCC, University Hospital and Medical Faculty Carl Gustav Carus, TU Dresden, 01062 Dresden, Germany; Max Planck Institute of Molecular Cell Biology and Genetics, 01307 Dresden, Germany
| | - Takashi Hiiragi
- Developmental Biology Unit, European Molecular Biology Laboratory (EMBL), 69117 Heidelberg, Germany.
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23
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Forceful patterning in mouse preimplantation embryos. Semin Cell Dev Biol 2017; 71:129-136. [PMID: 28577924 DOI: 10.1016/j.semcdb.2017.05.011] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2017] [Revised: 05/16/2017] [Accepted: 05/21/2017] [Indexed: 12/22/2022]
Abstract
The generation of a functional organism from a single, fertilized ovum requires the spatially coordinated regulation of diverse cell identities. The establishment and precise arrangement of differentiated cells in developing embryos has, historically, been extensively studied by geneticists and developmental biologists. While chemical gradients and genetic regulatory networks are widely acknowledged to play significant roles in embryo patterning, recent studies have highlighted that mechanical forces generated by, and exerted on, embryos are also crucial for the proper control of cell differentiation and morphogenesis. Here we review the most recent findings in murine preimplantation embryogenesis on the roles of cortical tension in the coupling of cell-fate determination and cell positioning in 8-16-cell-stage embryos. These basic principles of mechanochemical coupling in mouse embryos can be applied to other pattern formation phenomena that rely on localized modifications of cell polarity proteins and actin cytoskeletal components and activities.
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24
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Mouse blastomeres acquire ability to divide asymmetrically before compaction. PLoS One 2017; 12:e0175032. [PMID: 28362853 PMCID: PMC5376319 DOI: 10.1371/journal.pone.0175032] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2016] [Accepted: 03/20/2017] [Indexed: 11/23/2022] Open
Abstract
The mouse preimplantation embryo generates the precursors of trophectoderm (TE) and inner cell mass (ICM) during the 8- to 16-cell stage transition, when the apico-basal polarized blastomeres undergo divisions that give rise to cells with different fate. Asymmetric segregation of polar domain at 8–16 cell division generate two cell types, polar cells which adopt an outer position and develop in TE and apolar cells which are allocated to inner position as the precursors of ICM. It is still not know when the blastomeres of 8-cell stage start to be determined to undergo asymmetric division. Here, we analyze the frequency of symmetric and asymmetric divisions of blastomeres isolated from 8-cell stage embryo before and after compaction. Using p-Ezrin as the polarity marker we found that size of blastomeres in 2/16 pairs cannot be used as a criterion for distinguishing symmetric and asymmetric divisions. Our results showed that at early 8-cell stage, before any visible signs of cortical polarity, a subset of blastomeres had been already predestined to divide asymmetrically. We also showed that almost all of 8-cell stage blastomeres isolated from compacted embryo divide asymmetrically, whereas in intact embryos, the frequency of asymmetric divisions is significantly lower. Therefore we conclude that in intact embryo the frequency of symmetric and asymmetric division is regulated by cell-cell interactions.
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25
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Posfai E, Petropoulos S, de Barros FRO, Schell JP, Jurisica I, Sandberg R, Lanner F, Rossant J. Position- and Hippo signaling-dependent plasticity during lineage segregation in the early mouse embryo. eLife 2017; 6:22906. [PMID: 28226240 PMCID: PMC5370188 DOI: 10.7554/elife.22906] [Citation(s) in RCA: 99] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2016] [Accepted: 02/13/2017] [Indexed: 12/16/2022] Open
Abstract
The segregation of the trophectoderm (TE) from the inner cell mass (ICM) in the mouse blastocyst is determined by position-dependent Hippo signaling. However, the window of responsiveness to Hippo signaling, the exact timing of lineage commitment and the overall relationship between cell commitment and global gene expression changes are still unclear. Single-cell RNA sequencing during lineage segregation revealed that the TE transcriptional profile stabilizes earlier than the ICM and prior to blastocyst formation. Using quantitative Cdx2-eGFP expression as a readout of Hippo signaling activity, we assessed the experimental potential of individual blastomeres based on their level of Cdx2-eGFP expression and correlated potential with gene expression dynamics. We find that TE specification and commitment coincide and occur at the time of transcriptional stabilization, whereas ICM cells still retain the ability to regenerate TE up to the early blastocyst stage. Plasticity of both lineages is coincident with their window of sensitivity to Hippo signaling. DOI:http://dx.doi.org/10.7554/eLife.22906.001 In female mammals, conception is a complex process that involves several stages. First, an egg is released from the ovary and travels along a tube called the oviduct, where sperm from a male may fertilize it. If the egg is fertilized, the newly formed embryo moves into the womb, where it will then implant into the walls. In mice, it takes around four days for the embryo to implant and during this time, the cells in the embryo divide several times and start to specialize to form distinct cell types called lineages. The first two lineages to form are known as the inner cell mass and the trophectoderm. The inner cell mass forms a ball of cells within the embryo and contains the precursors of all cells that build the animal’s body. The trophectoderm forms a layer that surrounds the inner cell mass and will become part of the placenta (the organ that supplies the embryo with nutrients while it is in the womb). The embryo can organize these lineages without any instructions from the mother. However, it is still not clear when the cells start to differ from each other, and when they ‘commit’ to stay in these lineages. Cells in the inner cell mass and trophectoderm have different gene expression profiles, meaning that many genes display different levels of activity in these two lineages. Posfai et al. use a technique called single-cell RNA sequencing to analyse gene activity as the inner cell mass and trophectoderm form in mouse embryos. By measuring changes in gene activity, it is possible to track their development and show which genes change expression levels when each lineage specifies and commits. The experiments reveal that the inner cell mass and trophectoderm lineages develop at different times. As the inner cell mass forms, cells adopt the inner cell mass ‘identity’ before they commit to remaining in this lineage, revealing a window of time where different signals could still change the fate of the cells. However, when the early trophectoderm cells show the first signs of specialization, they also commit to their new identity at the same time. These findings suggest that the different timings at which these cell lineages form might provide embryos with the means to organize their own cells. An important future challenge is to understand exactly how the cells commit to their fate. DOI:http://dx.doi.org/10.7554/eLife.22906.002
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Affiliation(s)
- Eszter Posfai
- Program in Developmental and Stem Cell Biology, Hospital for Sick Children, Toronto, Canada
| | - Sophie Petropoulos
- Department of Clinical Science, Intervention and Technology, Karolinska Institutet, Stockholm, Sweden.,Ludwig Institute for Cancer Research, Karolinska Institutet, Stockholm, Sweden.,Division of Obstetrics and Gynecology, Karolinska Universitetssjukhuset, Stockholm, Sweden
| | | | - John Paul Schell
- Department of Clinical Science, Intervention and Technology, Karolinska Institutet, Stockholm, Sweden.,Division of Obstetrics and Gynecology, Karolinska Universitetssjukhuset, Stockholm, Sweden
| | - Igor Jurisica
- Princess Margaret Cancer Centre, University Health Network, University of Toronto, Toronto, Canada.,Departments of Medical Biophysics and Computer Science, University of Toronto, Toronto, Canada.,Institute of Neuroimmunology, Slovak Academy of Sciences, Bratislava, Slovakia
| | - Rickard Sandberg
- Ludwig Institute for Cancer Research, Karolinska Institutet, Stockholm, Sweden.,Department of Cell and Molecular Biology, Karolinska Institutet, Stockholm, Sweden
| | - Fredrik Lanner
- Department of Clinical Science, Intervention and Technology, Karolinska Institutet, Stockholm, Sweden.,Division of Obstetrics and Gynecology, Karolinska Universitetssjukhuset, Stockholm, Sweden
| | - Janet Rossant
- Program in Developmental and Stem Cell Biology, Hospital for Sick Children, Toronto, Canada.,Department of Molecular Genetics, University of Toronto, Toronto, Canada
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26
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Swain JE. Novel Imaging Techniques to Assess Gametes and Preimplantation Embryos. Hum Reprod 2016. [DOI: 10.1002/9781118849613.ch6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Affiliation(s)
- Jason E. Swain
- Center for Reproductive Medicine, Department of Obstetrics & Gynecology; University of Michigan; Ann Arbor MI USA
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27
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Menchero S, Rayon T, Andreu MJ, Manzanares M. Signaling pathways in mammalian preimplantation development: Linking cellular phenotypes to lineage decisions. Dev Dyn 2016; 246:245-261. [DOI: 10.1002/dvdy.24471] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2016] [Revised: 11/16/2016] [Accepted: 11/16/2016] [Indexed: 12/20/2022] Open
Affiliation(s)
- Sergio Menchero
- Centro Nacional de Investigaciones Cardiovasculares (CNIC); Madrid Spain
| | - Teresa Rayon
- Centro Nacional de Investigaciones Cardiovasculares (CNIC); Madrid Spain
| | - Maria Jose Andreu
- Centro Nacional de Investigaciones Cardiovasculares (CNIC); Madrid Spain
| | - Miguel Manzanares
- Centro Nacional de Investigaciones Cardiovasculares (CNIC); Madrid Spain
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28
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White MD, Zenker J, Bissiere S, Plachta N. How cells change shape and position in the early mammalian embryo. Curr Opin Cell Biol 2016; 44:7-13. [PMID: 28033492 DOI: 10.1016/j.ceb.2016.11.002] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2016] [Revised: 11/23/2016] [Accepted: 11/27/2016] [Indexed: 10/20/2022]
Abstract
During preimplantation development, cells of the mammalian embryo must resolve their shape and position to ensure the future viability of the fetus. These initial changes are established as the embryo expands from one to thirty-two cells, and a group of originally spherical cells is transformed into a more polarized structure with distinct cell geometries and lineages. Recent advances in the application of non-invasive imaging technologies have enabled the discovery of mechanisms regulating patterning of the early mammalian embryo. Here, we review recent findings revealing cell protrusions that trigger early changes in cell shape and embryo compaction, and how anisotropies in mechanical forces drive the first spatial segregation of cells in the embryo to form the pluripotent inner mass.
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Affiliation(s)
- Melanie D White
- Institute of Molecular and Cell Biology, A*STAR, 61 Biopolis Drive, Singapore 138673, Singapore
| | - Jennifer Zenker
- Institute of Molecular and Cell Biology, A*STAR, 61 Biopolis Drive, Singapore 138673, Singapore
| | - Stephanie Bissiere
- Institute of Molecular and Cell Biology, A*STAR, 61 Biopolis Drive, Singapore 138673, Singapore
| | - Nicolas Plachta
- Institute of Molecular and Cell Biology, A*STAR, 61 Biopolis Drive, Singapore 138673, Singapore.
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29
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Sepulveda-Rincon LP, Dube D, Adenot P, Laffont L, Ruffini S, Gall L, Campbell BK, Duranthon V, Beaujean N, Maalouf WE. Random Allocation of Blastomere Descendants to the Trophectoderm and ICM of the Bovine Blastocyst. Biol Reprod 2016; 95:123. [PMID: 27760750 PMCID: PMC5333943 DOI: 10.1095/biolreprod.116.141200] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2016] [Revised: 05/12/2016] [Accepted: 10/17/2016] [Indexed: 01/27/2023] Open
Abstract
The first lineage specification during mammalian embryo development can be visually distinguished at the blastocyst stage. Two cell lineages are observed on the embryonic-abembryonic axis of the blastocyst: the inner cell mass and the trophectoderm. The timing and mechanisms driving this process are still not fully understood. In mouse embryos, cells seem prepatterned to become certain cell lineage because the first cleavage plane has been related with further embryonic-abembryonic axis at the blastocyst stage. Nevertheless, this possibility has been very debatable. Our objective was to determine whether this would be the case in another mammalian species, the bovine. To achieve this, cells of in vitro produced bovine embryos were traced from the 2-cell stage to the blastocyst stage. Blastocysts were then classified according to the allocation of the labeled cells in the embryonic and/or abembryonic part of the blastocyst. Surprisingly, we found that there is a significant percentage of the embryos (∼60%) with labeled and nonlabeled cells randomly distributed and intermingled. Using time-lapse microscopy, we have identified the emergence of this random pattern at the third to fourth cell cycle, when cells started to intermingle. Even though no differences were found on morphokinetics among different embryos, these random blastocysts and those with labeled cells separated by the embryonic-abembryonic axis (deviant pattern) are significantly bigger; moreover deviant embryos have a significantly higher number of cells. Interestingly, we observed that daughter cells allocation at the blastocyst stage is not affected by biopsies performed at an earlier stage.
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Affiliation(s)
- Lessly P Sepulveda-Rincon
- Child Health, Obstetrics and Gynecology, School of Medicine, University of Nottingham, Nottingham, United Kingdom
| | - Delphine Dube
- UMR BDR, INRA, ENVA, Université Paris Saclay, Jouy en Josas, France
| | - Pierre Adenot
- UMR BDR, INRA, ENVA, Université Paris Saclay, Jouy en Josas, France
| | - Ludivine Laffont
- UMR BDR, INRA, ENVA, Université Paris Saclay, Jouy en Josas, France
| | - Sylvie Ruffini
- UMR BDR, INRA, ENVA, Université Paris Saclay, Jouy en Josas, France
| | - Laurence Gall
- UMR BDR, INRA, ENVA, Université Paris Saclay, Jouy en Josas, France
| | - Bruce K Campbell
- Child Health, Obstetrics and Gynecology, School of Medicine, University of Nottingham, Nottingham, United Kingdom
| | | | - Nathalie Beaujean
- UMR BDR, INRA, ENVA, Université Paris Saclay, Jouy en Josas, France
- Univ Lyon, Université de Lyon 1, Inserm, Bron, France
| | - Walid E Maalouf
- Child Health, Obstetrics and Gynecology, School of Medicine, University of Nottingham, Nottingham, United Kingdom
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30
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Wang S, Lakomy DS, Garcia MD, Lopez AL, Larin KV, Larina IV. Four-dimensional live imaging of hemodynamics in mammalian embryonic heart with Doppler optical coherence tomography. JOURNAL OF BIOPHOTONICS 2016; 9:837-47. [PMID: 26996292 PMCID: PMC5152918 DOI: 10.1002/jbio.201500314] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2015] [Revised: 02/03/2016] [Accepted: 03/01/2016] [Indexed: 05/19/2023]
Abstract
Hemodynamic analysis of the mouse embryonic heart is essential for understanding the functional aspects of early cardiogenesis and advancing the research in congenital heart defects. However, high-resolution imaging of cardiac hemodynamics in mammalian models remains challenging, primarily due to the dynamic nature and deep location of the embryonic heart. Here we report four-dimensional micro-scale imaging of blood flow in the early mouse embryonic heart, enabling time-resolved measurement and analysis of flow velocity throughout the heart tube. Our method uses Doppler optical coherence tomography in live mouse embryo culture, and employs a post-processing synchronization approach to reconstruct three-dimensional data over time at a 100 Hz volume rate. Experiments were performed on live mouse embryos at embryonic day 9.0. Our results show blood flow dynamics inside the beating heart, with the capability for quantitative flow velocity assessment in the primitive atrium, atrioventricular and bulboventricular regions, and bulbus cordis. Combined cardiodynamic and hemodynamic analysis indicates this functional imaging method can be utilized to further investigate the mechanical relationship between blood flow dynamics and cardiac wall movement, bringing new possibilities to study biomechanics in early mammalian cardiogenesis. Four-dimensional live hemodynamic imaging of the mouse embryonic heart at embryonic day 9.0 using Doppler optical coherence tomography, showing directional blood flows in the sinus venosus, primitive atrium, atrioventricular region and vitelline vein.
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Affiliation(s)
- Shang Wang
- Department of Molecular Physiology and Biophysics, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, U.S
| | - David S Lakomy
- Department of Molecular Physiology and Biophysics, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, U.S
| | - Monica D Garcia
- Department of Molecular Physiology and Biophysics, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, U.S
| | - Andrew L Lopez
- Department of Molecular Physiology and Biophysics, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, U.S
| | - Kirill V Larin
- Department of Molecular Physiology and Biophysics, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, U.S
- Department of Biomedical Engineering, University of Houston, 3605 Cullen Blvd., 77204, Houston, TX 77204, U.S
- Interdisciplinary Laboratory of Biophotonics, Tomsk State University, Tomsk, 634050, Russia
| | - Irina V Larina
- Department of Molecular Physiology and Biophysics, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, U.S..
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31
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Wang S, Lakomy DS, Garcia MD, Lopez AL, Larin KV, Larina IV. Four-dimensional live imaging of hemodynamics in mammalian embryonic heart with Doppler optical coherence tomography. JOURNAL OF BIOPHOTONICS 2016. [PMID: 26996292 DOI: 10.1002/jbio.v9.8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
Hemodynamic analysis of the mouse embryonic heart is essential for understanding the functional aspects of early cardiogenesis and advancing the research in congenital heart defects. However, high-resolution imaging of cardiac hemodynamics in mammalian models remains challenging, primarily due to the dynamic nature and deep location of the embryonic heart. Here we report four-dimensional micro-scale imaging of blood flow in the early mouse embryonic heart, enabling time-resolved measurement and analysis of flow velocity throughout the heart tube. Our method uses Doppler optical coherence tomography in live mouse embryo culture, and employs a post-processing synchronization approach to reconstruct three-dimensional data over time at a 100 Hz volume rate. Experiments were performed on live mouse embryos at embryonic day 9.0. Our results show blood flow dynamics inside the beating heart, with the capability for quantitative flow velocity assessment in the primitive atrium, atrioventricular and bulboventricular regions, and bulbus cordis. Combined cardiodynamic and hemodynamic analysis indicates this functional imaging method can be utilized to further investigate the mechanical relationship between blood flow dynamics and cardiac wall movement, bringing new possibilities to study biomechanics in early mammalian cardiogenesis. Four-dimensional live hemodynamic imaging of the mouse embryonic heart at embryonic day 9.0 using Doppler optical coherence tomography, showing directional blood flows in the sinus venosus, primitive atrium, atrioventricular region and vitelline vein.
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Affiliation(s)
- Shang Wang
- Department of Molecular Physiology and Biophysics, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, U.S
| | - David S Lakomy
- Department of Molecular Physiology and Biophysics, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, U.S
| | - Monica D Garcia
- Department of Molecular Physiology and Biophysics, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, U.S
| | - Andrew L Lopez
- Department of Molecular Physiology and Biophysics, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, U.S
| | - Kirill V Larin
- Department of Molecular Physiology and Biophysics, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, U.S
- Department of Biomedical Engineering, University of Houston, 3605 Cullen Blvd., 77204, Houston, TX 77204, U.S
- Interdisciplinary Laboratory of Biophotonics, Tomsk State University, Tomsk, 634050, Russia
| | - Irina V Larina
- Department of Molecular Physiology and Biophysics, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, U.S..
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Humięcka M, Krupa M, Guzewska MM, Maleszewski M, Suwińska A. ESCs injected into the 8-cell stage mouse embryo modify pattern of cleavage and cell lineage specification. Mech Dev 2016; 141:40-50. [PMID: 27345419 DOI: 10.1016/j.mod.2016.06.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2016] [Revised: 06/16/2016] [Accepted: 06/19/2016] [Indexed: 11/17/2022]
Abstract
During mouse embryogenesis initial specification of the cell fates depends on the type of division during 8- to 16- and 16- to 32-cell stage transition. A conservative division of a blastomere creates two polar outer daughter cells, which are precursors of the trophectoderm (TE), whereas a differentiative division gives rise to a polar outer cell and an apolar inner (the presumptive inner cell mass - ICM) cell. We hypothesize that the type of division may depend on the interactions between blastomeres of the embryo. To investigate whether modification of these interactions influences divisions, we analyzed the pattern of blastomere division and cell lineage specification in chimeric embryos obtained by injection of a different number of mouse embryonic stem cells (ESCs) into 8-cell embryos. As the ESCs populate only the ICM of the resulting chimeric blastocysts, they emulated in our model additional inner cells. We found that introduction of ESCs decreased the number of inner, apolar blastomeres at the 8- to 16-cell stage transition and reduced the number of ICM cells of host embryo-origin during formation of the blastocyst. Moreover, we showed that the proportion of inner blastomeres and their fate (EPI or PE) in chimeric blastocysts was dependent on the number of ESCs injected. Our results suggest the existence of a regulative mechanism, which links number of inner cells with a proportion of conservative vs. differentiative blastomere divisions during the cleavage and thus dictates their developmental fate.
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Affiliation(s)
- Monika Humięcka
- Department of Embryology, Faculty of Biology, University of Warsaw, Warsaw, Poland
| | - Magdalena Krupa
- Department of Embryology, Faculty of Biology, University of Warsaw, Warsaw, Poland
| | - Maria M Guzewska
- Department of Embryology, Faculty of Biology, University of Warsaw, Warsaw, Poland
| | - Marek Maleszewski
- Department of Embryology, Faculty of Biology, University of Warsaw, Warsaw, Poland.
| | - Aneta Suwińska
- Department of Embryology, Faculty of Biology, University of Warsaw, Warsaw, Poland.
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33
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Garg V, Morgani S, Hadjantonakis AK. Capturing Identity and Fate Ex Vivo: Stem Cells from the Mouse Blastocyst. Curr Top Dev Biol 2016; 120:361-400. [PMID: 27475857 DOI: 10.1016/bs.ctdb.2016.04.007] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
During mouse preimplantation development, three molecularly, morphologically, and spatially distinct lineages are formed, the embryonic epiblast, the extraembryonic primitive endoderm, and the trophectoderm. Stem cell lines representing each of these lineages have now been derived and can be indefinitely maintained and expanded in culture, providing an unlimited source of material to study the interplay of tissue-specific transcription factors and signaling pathways involved in these fundamental cell fate decisions. Here we outline our current understanding of the derivation, maintenance, and properties of these in vitro stem cell models representing the preimplantation embryonic lineages.
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Affiliation(s)
- V Garg
- Developmental Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY, United States; Biochemistry, Cell and Molecular Biology Program, Weill Cornell Graduate School of Medical Sciences, New York, NY, United States
| | - S Morgani
- Developmental Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY, United States
| | - A-K Hadjantonakis
- Developmental Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY, United States; Biochemistry, Cell and Molecular Biology Program, Weill Cornell Graduate School of Medical Sciences, New York, NY, United States.
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Lokken AA, Ralston A. The Genetic Regulation of Cell Fate During Preimplantation Mouse Development. Curr Top Dev Biol 2016; 120:173-202. [PMID: 27475852 DOI: 10.1016/bs.ctdb.2016.04.006] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The adult body is estimated to contain several hundred distinct cell types, each with a specialized physiological function. Failure to maintain cell fate can lead to devastating diseases and cancer, but understanding how cell fates are assigned and maintained during animal development provides new opportunities for human health intervention. The mouse is a premier model for evaluating the genetic regulation of cell fate during development because of the wide variety of tools for measuring and manipulating gene expression levels, the ability to access embryos at desired developmental stages, and the similarities between mouse and human development, particularly during the early stages of development. During the first 3 days of mouse development, the preimplantation embryo sets aside cells that will contribute to the extraembryonic tissues. The extraembryonic tissues are essential for establishing pregnancy and ensuring normal fetal development in both mice and humans. Genetic analyses of mouse preimplantation development have permitted identification of genes that are essential for specification of the extraembryonic lineages. In this chapter, we review the tools and concepts of mouse preimplantation development. We describe genes that are essential for cell fate specification during preimplantation stages, and we describe diverse models proposed to account for the mechanisms of cell fate specification during early development.
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Affiliation(s)
- A A Lokken
- Michigan State University, East Lansing, MI, United States
| | - A Ralston
- Michigan State University, East Lansing, MI, United States.
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35
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Chazaud C, Yamanaka Y. Lineage specification in the mouse preimplantation embryo. Development 2016; 143:1063-74. [DOI: 10.1242/dev.128314] [Citation(s) in RCA: 199] [Impact Index Per Article: 24.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
During mouse preimplantation embryo development, totipotent blastomeres generate the first three cell lineages of the embryo: trophectoderm, epiblast and primitive endoderm. In recent years, studies have shown that this process appears to be regulated by differences in cell-cell interactions, gene expression and the microenvironment of individual cells, rather than the active partitioning of maternal determinants. Precisely how these differences first emerge and how they dictate subsequent molecular and cellular behaviours are key questions in the field. As we review here, recent advances in live imaging, computational modelling and single-cell transcriptome analyses are providing new insights into these questions.
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Affiliation(s)
- Claire Chazaud
- Université Clermont Auvergne, Laboratoire GReD, Clermont-Ferrand F-63000, France
- Inserm, UMR1103, Clermont-Ferrand F-63001, France
- CNRS, UMR6293, Clermont-Ferrand F-63001, France
| | - Yojiro Yamanaka
- Goodman Cancer Research Centre, Department of Human Genetics, McGill University, 1160 Pine Avenue West, rm419, Montreal, Quebec, Canada H3A 1A3
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36
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Goolam M, Scialdone A, Graham SJL, Macaulay IC, Jedrusik A, Hupalowska A, Voet T, Marioni JC, Zernicka-Goetz M. Heterogeneity in Oct4 and Sox2 Targets Biases Cell Fate in 4-Cell Mouse Embryos. Cell 2016; 165:61-74. [PMID: 27015307 PMCID: PMC4819611 DOI: 10.1016/j.cell.2016.01.047] [Citation(s) in RCA: 291] [Impact Index Per Article: 36.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2015] [Revised: 11/10/2015] [Accepted: 01/22/2016] [Indexed: 01/08/2023]
Abstract
The major and essential objective of pre-implantation development is to establish embryonic and extra-embryonic cell fates. To address when and how this fundamental process is initiated in mammals, we characterize transcriptomes of all individual cells throughout mouse pre-implantation development. This identifies targets of master pluripotency regulators Oct4 and Sox2 as being highly heterogeneously expressed between blastomeres of the 4-cell embryo, with Sox21 showing one of the most heterogeneous expression profiles. Live-cell tracking demonstrates that cells with decreased Sox21 yield more extra-embryonic than pluripotent progeny. Consistently, decreasing Sox21 results in premature upregulation of the differentiation regulator Cdx2, suggesting that Sox21 helps safeguard pluripotency. Furthermore, Sox21 is elevated following increased expression of the histone H3R26-methylase CARM1 and is lowered following CARM1 inhibition, indicating the importance of epigenetic regulation. Therefore, our results indicate that heterogeneous gene expression, as early as the 4-cell stage, initiates cell-fate decisions by modulating the balance of pluripotency and differentiation.
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Affiliation(s)
- Mubeen Goolam
- Department of Physiology, Development & Neuroscience, University of Cambridge, Downing Street, Cambridge CB2 3EG, UK
| | - Antonio Scialdone
- European Bioinformatics Institute, European Molecular Biology Laboratory (EMBL-EBI), Wellcome Genome Campus, Cambridge CB10 1SD, UK; Wellcome Trust Sanger Institute, Wellcome Genome Campus, Cambridge CB10 1SA, UK
| | - Sarah J L Graham
- Department of Physiology, Development & Neuroscience, University of Cambridge, Downing Street, Cambridge CB2 3EG, UK
| | - Iain C Macaulay
- Wellcome Trust Sanger Institute, Wellcome Genome Campus, Cambridge CB10 1SA, UK
| | - Agnieszka Jedrusik
- Department of Physiology, Development & Neuroscience, University of Cambridge, Downing Street, Cambridge CB2 3EG, UK
| | - Anna Hupalowska
- Department of Physiology, Development & Neuroscience, University of Cambridge, Downing Street, Cambridge CB2 3EG, UK
| | - Thierry Voet
- Wellcome Trust Sanger Institute, Wellcome Genome Campus, Cambridge CB10 1SA, UK; Laboratory of Reproductive Genomics, Department of Human Genetics, KU Leuven, Herestraat 49, 3000 Leuven, Belgium
| | - John C Marioni
- European Bioinformatics Institute, European Molecular Biology Laboratory (EMBL-EBI), Wellcome Genome Campus, Cambridge CB10 1SD, UK; Wellcome Trust Sanger Institute, Wellcome Genome Campus, Cambridge CB10 1SA, UK; Cancer Research UK-Cambridge Institute, University of Cambridge, Li Ka Shing Centre, Cambridge CB2 0RE, UK.
| | - Magdalena Zernicka-Goetz
- Department of Physiology, Development & Neuroscience, University of Cambridge, Downing Street, Cambridge CB2 3EG, UK.
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37
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Toyooka Y, Oka S, Fujimori T. Early preimplantation cells expressing Cdx2 exhibit plasticity of specification to TE and ICM lineages through positional changes. Dev Biol 2016; 411:50-60. [PMID: 26806703 DOI: 10.1016/j.ydbio.2016.01.011] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2015] [Revised: 10/28/2015] [Accepted: 01/20/2016] [Indexed: 10/22/2022]
Abstract
The establishment of the trophectoderm (TE) and the inner cell mass (ICM) is the first cell lineage segregation to occur in mouse preimplantation development. These two cell lineages arise in a position-dependent manner at the blastocyst stage: the outer cells form TE, which will generate the future placenta, while the inner cells give rise to the ICM, from which the epiblast (EPI) and primitive endoderm (PrE) arise. Previous studies have shown that a portion of cells relocate from the outside position to the inside during this preimplantation stage, but few studies have investigated the correlation between cell relocation and the expression of key transcription factors critical for cell differentiation. To monitor cell movement and the status of the TE-specification pathway in living embryos, we established Cdx2-GFP reporter mice allowing us to visualize the expression of Caudal-type transcriptional factor (Cdx2), a key regulator of the initiation of TE differentiation. Observation of Cdx2-GFP preimplantation embryos by live cell imaging revealed that all cells localized in an initial outer position initiated the expression of Cdx2. Subsequently, cells that changed their position from an outer to an inner position downregulated Cdx2 expression and contributed to the ICM. Finally we showed that internalized cells likely contribute to both the EPI and PrE. Our datas indicate that cells expressing even high levels of Cdx2 can internalize, deactivate an activated TE-specification molecular pathway and integrate into the pluripotent cell population.
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Affiliation(s)
- Yayoi Toyooka
- Division of Embryology, National Institute for Basic Biology, Okazaki, Japan; Department of Basic Biology, School of Life Science, SOKENDAI (The Graduate University for Advanced Studies), Okazaki, Aichi, Japan.
| | - Sanae Oka
- Division of Embryology, National Institute for Basic Biology, Okazaki, Japan
| | - Toshihiko Fujimori
- Division of Embryology, National Institute for Basic Biology, Okazaki, Japan; Department of Basic Biology, School of Life Science, SOKENDAI (The Graduate University for Advanced Studies), Okazaki, Aichi, Japan.
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38
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Frankenberg SR, de Barros FR, Rossant J, Renfree MB. The mammalian blastocyst. WILEY INTERDISCIPLINARY REVIEWS-DEVELOPMENTAL BIOLOGY 2016; 5:210-32. [DOI: 10.1002/wdev.220] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/12/2015] [Revised: 10/22/2015] [Accepted: 10/29/2015] [Indexed: 11/10/2022]
Affiliation(s)
| | - Flavia R.O. de Barros
- Program in Developmental and Stem Cell Biology; Peter Gilgan Centre for Research and Learning, Hospital for Sick Children; Toronto Canada
- Department of Molecular Genetics; University of Toronto; Toronto Canada
| | - Janet Rossant
- Program in Developmental and Stem Cell Biology; Peter Gilgan Centre for Research and Learning, Hospital for Sick Children; Toronto Canada
- Department of Molecular Genetics; University of Toronto; Toronto Canada
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39
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Wong CY, Mills JK. Automation and optimization of multi-pulse laser zona drilling of mouse embryos during embryo biopsy. IEEE Trans Biomed Eng 2016; 64:629-636. [DOI: 10.1109/tbme.2016.2571060] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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40
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Graham SJ, Zernicka-Goetz M. The Acquisition of Cell Fate in Mouse Development. Curr Top Dev Biol 2016; 117:671-95. [DOI: 10.1016/bs.ctdb.2015.11.021] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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41
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Bessonnard S, Mesnard D, Constam DB. PC7 and the related proteases Furin and Pace4 regulate E-cadherin function during blastocyst formation. J Cell Biol 2015; 210:1185-97. [PMID: 26416966 PMCID: PMC4586756 DOI: 10.1083/jcb.201503042] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Targeted deletion of PC7 and the related proprotein convertases Furin and Pace4, combined with live imaging of their activities, unmasks their overlapping and complementary functions in morula compaction and ICM formation in mouse blastocysts and in E-cadherin precursor processing. The first cell differentiation in mammalian embryos segregates polarized trophectoderm cells from an apolar inner cell mass (ICM). This lineage decision is specified in compacted morulae by cell polarization and adhesion acting on the Yes-associated protein in the Hippo signaling pathway, but the regulatory mechanisms are unclear. We show that morula compaction and ICM formation depend on PC7 and the related proprotein convertases (PCs) Furin and Pace4 and that these proteases jointly regulate cell–cell adhesion mediated by E-cadherin processing. We also mapped the spatiotemporal activity profiles of these proteases by live imaging of a transgenic reporter substrate in wild-type and PC mutant embryos. Differential inhibition by a common inhibitor revealed that all three PCs are active in inner and outer cells, but in partially nonoverlapping compartments. E-cadherin processing by multiple PCs emerges as a novel mechanism to modulate cell–cell adhesion and fate allocation.
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Affiliation(s)
- Sylvain Bessonnard
- Swiss Federal Institute of Technology in Lausanne, School of Life Sciences, Swiss Institute for Experimental Cancer Research, 1015 Lausanne, Switzerland
| | - Daniel Mesnard
- Swiss Federal Institute of Technology in Lausanne, School of Life Sciences, Swiss Institute for Experimental Cancer Research, 1015 Lausanne, Switzerland
| | - Daniel B Constam
- Swiss Federal Institute of Technology in Lausanne, School of Life Sciences, Swiss Institute for Experimental Cancer Research, 1015 Lausanne, Switzerland
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42
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Strnad P, Gunther S, Reichmann J, Krzic U, Balazs B, de Medeiros G, Norlin N, Hiiragi T, Hufnagel L, Ellenberg J. Inverted light-sheet microscope for imaging mouse pre-implantation development. Nat Methods 2015; 13:139-42. [DOI: 10.1038/nmeth.3690] [Citation(s) in RCA: 117] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2015] [Accepted: 11/17/2015] [Indexed: 12/23/2022]
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43
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Hirate Y, Hirahara S, Inoue KI, Kiyonari H, Niwa H, Sasaki H. Par-aPKC-dependent and -independent mechanisms cooperatively control cell polarity, Hippo signaling, and cell positioning in 16-cell stage mouse embryos. Dev Growth Differ 2015; 57:544-56. [PMID: 26450797 DOI: 10.1111/dgd.12235] [Citation(s) in RCA: 58] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2015] [Revised: 07/11/2015] [Accepted: 07/12/2015] [Indexed: 12/24/2022]
Abstract
In preimplantation mouse embryos, the Hippo signaling pathway plays a central role in regulating the fates of the trophectoderm (TE) and the inner cell mass (ICM). In early blastocysts with more than 32 cells, the Par-aPKC system controls polarization of the outer cells along the apicobasal axis, and cell polarity suppresses Hippo signaling. Inactivation of Hippo signaling promotes nuclear accumulation of a coactivator protein, Yap, leading to induction of TE-specific genes. However, whether similar mechanisms operate at earlier stages is not known. Here, we show that slightly different mechanisms operate in 16-cell stage embryos. Similar to 32-cell stage embryos, disruption of the Par-aPKC system activated Hippo signaling and suppressed nuclear Yap and Cdx2 expression in the outer cells. However, unlike 32-cell stage embryos, 16-cell stage embryos with a disrupted Par-aPKC system maintained apical localization of phosphorylated Ezrin/Radixin/Moesin (p-ERM), and the effects on Yap and Cdx2 were weak. Furthermore, normal 16-cell stage embryos often contained apolar cells in the outer position. In these cells, the Hippo pathway was strongly activated and Yap was excluded from the nuclei, thus resembling inner cells. Dissociated blastomeres of 8-cell stage embryos form polar-apolar couplets, which exhibit different levels of nuclear Yap, and the polar cell engulfed the apolar cell. These results suggest that cell polarization at the 16-cell stage is regulated by both Par-aPKC-dependent and -independent mechanisms. Asymmetric cell division is involved in cell polarity control, and cell polarity regulates cell positioning and most likely controls Hippo signaling.
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Affiliation(s)
- Yoshikazu Hirate
- Department of Cell Fate Control, Institute of Molecular Embryology and Genetics, Kumamoto University, 2-2-1 Honjo, Chuo-ku, Kumamoto, 860-0811, Japan
| | - Shino Hirahara
- Laboratory for Embryonic Induction, RIKEN Center for Developmental Biology, 2-2-3 Minatojima-minamimachi, Chuo-ku, Kobe, Hyogo, 650-0047, Japan
| | - Ken-Ichi Inoue
- Animal Resource Development Unit, Division of Bio-function Dynamics Imaging, RIKEN Center for Life Science Technologies, 2-2-3 Minatojima-minamimachi, Chuo-ku, Kobe, Hyogo, 650-0047, Japan
| | - Hiroshi Kiyonari
- Animal Resource Development Unit, Division of Bio-function Dynamics Imaging, RIKEN Center for Life Science Technologies, 2-2-3 Minatojima-minamimachi, Chuo-ku, Kobe, Hyogo, 650-0047, Japan.,Genetic Engineering Team, Division of Bio-function Dynamics Imaging, RIKEN Center for Life Science Technologies, 2-2-3 Minatojima-minamimachi, Chuo-ku, Kobe, Hyogo, 650-0047, Japan
| | - Hiroshi Niwa
- Laboratory for Pluripotent Cell Studies, RIKEN Center for Developmental Biology, 2-2-3 Minatojima-minamimachi, Chuo-ku, Kobe, Hyogo, 650-0047, Japan.,Department of Stem Cell Biology, Institute of Molecular Embryology and Genetics, Kumamoto University, 2-2-1 Honjo, Chuo-ku, Kumamoto, 860-0811, Japan
| | - Hiroshi Sasaki
- Department of Cell Fate Control, Institute of Molecular Embryology and Genetics, Kumamoto University, 2-2-1 Honjo, Chuo-ku, Kumamoto, 860-0811, Japan.,Laboratory for Embryogenesis, Graduate School of Frontier BioSciences, Osaka University, 1-3 Yamadaoka, Suita, Osaka, 565-0871, Japan
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44
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Biggins JS, Royer C, Watanabe T, Srinivas S. Towards understanding the roles of position and geometry on cell fate decisions during preimplantation development. Semin Cell Dev Biol 2015; 47-48:74-9. [PMID: 26349030 PMCID: PMC4683091 DOI: 10.1016/j.semcdb.2015.09.006] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2015] [Revised: 09/01/2015] [Accepted: 09/02/2015] [Indexed: 01/15/2023]
Abstract
The first lineage segregation event in mouse embryos produces two separate cell populations: inner cell mass and trophectoderm. This is understood to be brought about by cells sensing their position within the embryo and differentiating accordingly. The cellular and molecular underpinnings of this process remain under investigation and have variously been considered to be completely stochastic or alternately, subject to some predisposition set up at fertilisation or before. Here, we consider these views in light of recent publications, discuss the possible role of cell geometry and mechanical forces in this process and describe how modelling could contribute in addressing this issue.
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Affiliation(s)
- John S Biggins
- Cavendish Laboratory, University of Cambridge, Cambridge, UK
| | - Christophe Royer
- Department of Physiology Anatomy and Genetics, University of Oxford, Oxford, UK
| | - Tomoko Watanabe
- Department of Physiology Anatomy and Genetics, University of Oxford, Oxford, UK
| | - Shankar Srinivas
- Department of Physiology Anatomy and Genetics, University of Oxford, Oxford, UK.
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45
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Samarage C, White M, Álvarez Y, Fierro-González J, Henon Y, Jesudason E, Bissiere S, Fouras A, Plachta N. Cortical Tension Allocates the First Inner Cells of the Mammalian Embryo. Dev Cell 2015; 34:435-47. [DOI: 10.1016/j.devcel.2015.07.004] [Citation(s) in RCA: 126] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2015] [Revised: 05/18/2015] [Accepted: 07/13/2015] [Indexed: 01/08/2023]
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46
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Single cells get together: High-resolution approaches to study the dynamics of early mouse development. Semin Cell Dev Biol 2015; 47-48:92-100. [PMID: 26183190 DOI: 10.1016/j.semcdb.2015.06.004] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2015] [Revised: 06/17/2015] [Accepted: 06/19/2015] [Indexed: 11/22/2022]
Abstract
Embryonic development is a complex and highly dynamic process during which individual cells interact with one another, adopt different identities and organize themselves in three-dimensional space to generate an entire organism. Recent technical developments in genomics and high-resolution quantitative imaging are making it possible to study cellular populations at single-cell resolution and begin to integrate different inputs, for example genetic, physical and chemical factors, that affect cell differentiation over spatial and temporal scales. The preimplantation mouse embryo allows the analysis of cell fate decisions in vivo with high spatiotemporal resolution. In this review we highlight how the application of live imaging and single-cell resolution analysis pipelines is providing an unprecedented level of insight on the processes that shape the earliest stages of mammalian development.
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47
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Dietrich JE, Panavaite L, Gunther S, Wennekamp S, Groner AC, Pigge A, Salvenmoser S, Trono D, Hufnagel L, Hiiragi T. Venus trap in the mouse embryo reveals distinct molecular dynamics underlying specification of first embryonic lineages. EMBO Rep 2015; 16:1005-21. [PMID: 26142281 DOI: 10.15252/embr.201540162] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2015] [Accepted: 06/02/2015] [Indexed: 12/31/2022] Open
Abstract
Mammalian development begins with the segregation of embryonic and extra-embryonic lineages in the blastocyst. Recent studies revealed cell-to-cell gene expression heterogeneity and dynamic cell rearrangements during mouse blastocyst formation. Thus, mechanistic understanding of lineage specification requires quantitative description of gene expression dynamics at a single-cell resolution in living embryos. However, only a few fluorescent gene expression reporter mice are available and quantitative live image analysis is limited so far. Here, we carried out a fluorescence gene-trap screen and established reporter mice expressing Venus specifically in the first lineages. Lineage tracking, quantitative gene expression and cell position analyses allowed us to build a comprehensive lineage map of mouse pre-implantation development. Our systematic analysis revealed that, contrary to the available models, the timing and mechanism of lineage specification may be distinct between the trophectoderm and the inner cell mass. While expression of our trophectoderm-specific lineage marker is upregulated in outside cells upon asymmetric divisions at 8- and 16-cell stages, the inside-specific upregulation of the inner-cell-mass marker only becomes evident at the 64-cell stage. This study thus provides a framework toward systems-level understanding of embryogenesis marked by high dynamicity and stochastic variability.
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Affiliation(s)
- Jens-Erik Dietrich
- Developmental Biology Unit, European Molecular Biology Laboratory (EMBL), Heidelberg, Germany
| | - Laura Panavaite
- Developmental Biology Unit, European Molecular Biology Laboratory (EMBL), Heidelberg, Germany
| | - Stefan Gunther
- Cell Biology and Biophysics Unit, European Molecular Biology Laboratory (EMBL), Heidelberg, Germany
| | - Sebastian Wennekamp
- Developmental Biology Unit, European Molecular Biology Laboratory (EMBL), Heidelberg, Germany
| | - Anna C Groner
- School of Life Sciences Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - Anton Pigge
- Max Planck Institute for Molecular Biomedicine, Muenster, Germany
| | - Stefanie Salvenmoser
- Developmental Biology Unit, European Molecular Biology Laboratory (EMBL), Heidelberg, Germany
| | - Didier Trono
- School of Life Sciences Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - Lars Hufnagel
- Cell Biology and Biophysics Unit, European Molecular Biology Laboratory (EMBL), Heidelberg, Germany
| | - Takashi Hiiragi
- Developmental Biology Unit, European Molecular Biology Laboratory (EMBL), Heidelberg, Germany
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48
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Hermitte S, Chazaud C. Primitive endoderm differentiation: from specification to epithelium formation. Philos Trans R Soc Lond B Biol Sci 2015; 369:rstb.2013.0537. [PMID: 25349446 DOI: 10.1098/rstb.2013.0537] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
In amniotes, primitive endoderm (PrE) plays important roles not only for nutrient support but also as an inductive tissue required for embryo patterning. PrE is an epithelial monolayer that is visible shortly before embryo implantation and is one of the first three cell lineages produced by the embryo. We review here the molecular mechanisms that have been uncovered during the past 10 years on PrE and epiblast cell lineage specification within the inner cell mass of the blastocyst and on their subsequent steps of differentiation.
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Affiliation(s)
- Stéphanie Hermitte
- Clermont Université, Université d'Auvergne, Laboratoire GReD, BP 10448, 63000 Clermont-Ferrand, France INSERM, UMR1103, 63001 Clermont-Ferrand, France CNRS, UMR6293, 63001 Clermont-Ferrand, France
| | - Claire Chazaud
- Clermont Université, Université d'Auvergne, Laboratoire GReD, BP 10448, 63000 Clermont-Ferrand, France INSERM, UMR1103, 63001 Clermont-Ferrand, France CNRS, UMR6293, 63001 Clermont-Ferrand, France
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49
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Sasaki H. Position- and polarity-dependent Hippo signaling regulates cell fates in preimplantation mouse embryos. Semin Cell Dev Biol 2015; 47-48:80-7. [PMID: 25986053 DOI: 10.1016/j.semcdb.2015.05.003] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2015] [Revised: 05/08/2015] [Accepted: 05/08/2015] [Indexed: 11/25/2022]
Abstract
During the preimplantation stage, mouse embryos establish two cell lineages by the time of early blastocyst formation: the trophectoderm (TE) and the inner cell mass (ICM). Historical models have proposed that the establishment of these two lineages depends on the cell position within the embryo (e.g., the positional model) or cell polarization along the apicobasal axis (e.g., the polarity model). Recent findings have revealed that the Hippo signaling pathway plays a central role in the cell fate-specification process: active and inactive Hippo signaling in the inner and outer cells promote ICM and TE fates, respectively. Intercellular adhesion activates, while apicobasal polarization suppresses Hippo signaling, and a combination of these processes determines the spatially regulated activation of the Hippo pathway in 32-cell-stage embryos. Therefore, there is experimental evidence in favor of both positional and polarity models. At the molecular level, phosphorylation of the Hippo-pathway component angiomotin at adherens junctions (AJs) in the inner (apolar) cells activates the Lats protein kinase and triggers Hippo signaling. In the outer cells, however, cell polarization sequesters Amot from basolateral AJs and suppresses activation of the Hippo pathway. Other mechanisms, including asymmetric cell division and Notch signaling, also play important roles in the regulation of embryonic development. In this review, I discuss how these mechanisms cooperate with the Hippo signaling pathway during cell fate-specification processes.
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Affiliation(s)
- Hiroshi Sasaki
- Laboratory for Embryogenesis, Graduate School of Frontier Biosciences, Osaka University, 1-3 Yamadaoka, Suita, Osaka 565-0871, Japan.
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50
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Watanabe T, Biggins JS, Tannan NB, Srinivas S. Limited predictive value of blastomere angle of division in trophectoderm and inner cell mass specification. Development 2014; 141:2279-88. [PMID: 24866117 PMCID: PMC4034423 DOI: 10.1242/dev.103267] [Citation(s) in RCA: 81] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
The formation of trophectoderm (TE) and pluripotent inner cell mass (ICM) is one of the earliest events during mammalian embryogenesis. It is believed that the orientation of division of polarised blastomeres in the 8- and 16-cell stage embryo determines the fate of daughter cells, based on how asymmetrically distributed lineage determinants are segregated. To investigate the relationship between angle of division and subsequent fate in unperturbed embryos, we constructed cellular resolution digital representations of the development of mouse embryos from the morula to early blastocyst stage, based on 4D confocal image volumes. We find that at the 16-cell stage, very few inside cells are initially produced as a result of cell division, but that the number increases due to cell movement. Contrary to expectations, outside cells at the 16-cell stage represent a heterogeneous population, with some fated to contributing exclusively to the TE and others capable of contributing to both the TE and ICM. Our data support the view that factors other than the angle of division, such as the position of a blastomere, play a major role in the specification of TE and ICM.
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Affiliation(s)
- Tomoko Watanabe
- Department of Physiology Anatomy and Genetics, University of Oxford, Oxford OX1 3QX, UK
| | - John S Biggins
- Cavendish Laboratory, University of Cambridge, Cambridge CB3 0HE, UK
| | - Neeta Bala Tannan
- Department of Physiology Anatomy and Genetics, University of Oxford, Oxford OX1 3QX, UK
| | - Shankar Srinivas
- Department of Physiology Anatomy and Genetics, University of Oxford, Oxford OX1 3QX, UK
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