1
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Pfeffer PL. The first lineage determination in mammals. Dev Biol 2024; 513:12-30. [PMID: 38761966 DOI: 10.1016/j.ydbio.2024.05.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2023] [Revised: 03/15/2024] [Accepted: 05/16/2024] [Indexed: 05/20/2024]
Abstract
This review describes in detail the morphological, cytoskeletal and gene expression events leading to the gene regulatory network bifurcation point of trophoblast and inner cell mass cells in a variety of mammalian preimplantation embryos. The interrelated processes of compaction and polarity establishment are discussed in terms of how they affect YAP/WWTR activity and the location and fate of cells. Comparisons between mouse, human, cattle, pig and rabbit embryos suggest a conserved role for YAP/WWTR signalling in trophoblast induction in eutherian animals though the mechanisms for, and timing of, YAP/WWTR activation differs among species. Downstream targets show further differences, with the trophoblast marker GATA3 being a direct target in all examined mammals, while CDX2-positive and SOX2-negative regulation varies.
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Affiliation(s)
- Peter L Pfeffer
- School of Biological Sciences, Victoria University of Wellington, Wellington, New Zealand.
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2
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Brückner DB, Tkačik G. Information content and optimization of self-organized developmental systems. Proc Natl Acad Sci U S A 2024; 121:e2322326121. [PMID: 38819997 PMCID: PMC11161761 DOI: 10.1073/pnas.2322326121] [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: 12/18/2023] [Accepted: 04/27/2024] [Indexed: 06/02/2024] Open
Abstract
A key feature of many developmental systems is their ability to self-organize spatial patterns of functionally distinct cell fates. To ensure proper biological function, such patterns must be established reproducibly, by controlling and even harnessing intrinsic and extrinsic fluctuations. While the relevant molecular processes are increasingly well understood, we lack a principled framework to quantify the performance of such stochastic self-organizing systems. To that end, we introduce an information-theoretic measure for self-organized fate specification during embryonic development. We show that the proposed measure assesses the total information content of fate patterns and decomposes it into interpretable contributions corresponding to the positional and correlational information. By optimizing the proposed measure, our framework provides a normative theory for developmental circuits, which we demonstrate on lateral inhibition, cell type proportioning, and reaction-diffusion models of self-organization. This paves a way toward a classification of developmental systems based on a common information-theoretic language, thereby organizing the zoo of implicated chemical and mechanical signaling processes.
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Affiliation(s)
- David B. Brückner
- Institute of Science and Technology Austria, AT-3400Klosterneuburg, Austria
| | - Gašper Tkačik
- Institute of Science and Technology Austria, AT-3400Klosterneuburg, Austria
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3
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Wauford N, Patel A, Tordoff J, Enghuus C, Jin A, Toppen J, Kemp ML, Weiss R. Synthetic symmetry breaking and programmable multicellular structure formation. Cell Syst 2023; 14:806-818.e5. [PMID: 37689062 PMCID: PMC10919224 DOI: 10.1016/j.cels.2023.08.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Revised: 04/14/2023] [Accepted: 08/02/2023] [Indexed: 09/11/2023]
Abstract
During development, cells undergo symmetry breaking into differentiated subpopulations that self-organize into complex structures.1,2,3,4,5 However, few tools exist to recapitulate these behaviors in a controllable and coupled manner.6,7,8,9 Here, we engineer a stochastic recombinase genetic switch tunable by small molecules to induce programmable symmetry breaking, commitment to downstream cell fates, and morphological self-organization. Inducers determine commitment probabilities, generating tunable subpopulations as a function of inducer dosage. We use this switch to control the cell-cell adhesion properties of cells committed to each fate.10,11 We generate a wide variety of 3D morphologies from a monoclonal population and develop a computational model showing high concordance with experimental results, yielding new quantitative insights into the relationship between cell-cell adhesion strengths and downstream morphologies. We expect that programmable symmetry breaking, generating precise and tunable subpopulation ratios and coupled to structure formation, will serve as an integral component of the toolbox for complex tissue and organoid engineering.
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Affiliation(s)
- Noreen Wauford
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Akshay Patel
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Jesse Tordoff
- Program in Computational and Systems Biology, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Casper Enghuus
- Department of Microbiology, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Andrew Jin
- The Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, USA
| | - Jack Toppen
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, GA, USA
| | - Melissa L Kemp
- The Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, USA
| | - Ron Weiss
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA; Department of Electrical Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA.
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4
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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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5
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Repina NA, Johnson HJ, Bao X, Zimmermann JA, Joy DA, Bi SZ, Kane RS, Schaffer DV. Optogenetic control of Wnt signaling models cell-intrinsic embryogenic patterning using 2D human pluripotent stem cell culture. Development 2023; 150:dev201386. [PMID: 37401411 PMCID: PMC10399980 DOI: 10.1242/dev.201386] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Accepted: 06/21/2023] [Indexed: 07/05/2023]
Abstract
In embryonic stem cell (ESC) models for early development, spatially and temporally varying patterns of signaling and cell types emerge spontaneously. However, mechanistic insight into this dynamic self-organization is limited by a lack of methods for spatiotemporal control of signaling, and the relevance of signal dynamics and cell-to-cell variability to pattern emergence remains unknown. Here, we combine optogenetic stimulation, imaging and transcriptomic approaches to study self-organization of human ESCs (hESC) in two-dimensional (2D) culture. Morphogen dynamics were controlled via optogenetic activation of canonical Wnt/β-catenin signaling (optoWnt), which drove broad transcriptional changes and mesendoderm differentiation at high efficiency (>99% cells). When activated within cell subpopulations, optoWnt induced cell self-organization into distinct epithelial and mesenchymal domains, mediated by changes in cell migration, an epithelial to mesenchymal-like transition and TGFβ signaling. Furthermore, we demonstrate that such optogenetic control of cell subpopulations can be used to uncover signaling feedback mechanisms between neighboring cell types. These findings reveal that cell-to-cell variability in Wnt signaling is sufficient to generate tissue-scale patterning and establish a hESC model system for investigating feedback mechanisms relevant to early human embryogenesis.
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Affiliation(s)
- Nicole A. Repina
- Department of Bioengineering, University of California, Berkeley, CA 94720, USA
- Graduate Program in Bioengineering, University of California, San Francisco and University of California, Berkeley, CA 94720, USA
| | - Hunter J. Johnson
- Department of Bioengineering, University of California, Berkeley, CA 94720, USA
- Graduate Program in Bioengineering, University of California, San Francisco and University of California, Berkeley, CA 94720, USA
| | - Xiaoping Bao
- Department of Chemical and Biomolecular Engineering, University of California, Berkeley, CA 94720, USA
| | - Joshua A. Zimmermann
- Department of Chemical and Biomolecular Engineering, University of California, Berkeley, CA 94720, USA
| | - David A. Joy
- Graduate Program in Bioengineering, University of California, San Francisco and University of California, Berkeley, CA 94720, USA
- Gladstone Institute of Cardiovascular Disease, Gladstone Institutes, San Francisco, CA 94158, USA
| | - Shirley Z. Bi
- Department of Bioengineering, University of California, Berkeley, CA 94720, USA
| | - Ravi S. Kane
- School of Chemical and Biomolecular Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA
| | - David V. Schaffer
- Department of Bioengineering, University of California, Berkeley, CA 94720, USA
- Department of Chemical and Biomolecular Engineering, University of California, Berkeley, CA 94720, USA
- Helen Wills Neuroscience Institute, University of California, Berkeley, CA 94720, USA
- Department of Molecular and Cell Biology, University of California, Berkeley, CA 94720, USA
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6
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Abstract
Organ development and homeostasis involve dynamic interactions between individual cells that collectively regulate tissue architecture and function. To ensure the highest tissue fidelity, equally fit cell populations are continuously renewed by stochastic replacement events, while cells perceived as less fit are actively removed by their fitter counterparts. This renewal is mediated by surveillance mechanisms that are collectively known as cell competition. Recent studies have revealed that cell competition has roles in most, if not all, developing and adult tissues. They have also established that cell competition functions both as a tumour-suppressive mechanism and as a tumour-promoting mechanism, thereby critically influencing cancer initiation and development. This Review discusses the latest insights into the mechanisms of cell competition and its different roles during embryonic development, homeostasis and cancer.
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7
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Chowdhary S, Hadjantonakis AK. Journey of the mouse primitive endoderm: from specification to maturation. Philos Trans R Soc Lond B Biol Sci 2022; 377:20210252. [PMID: 36252215 PMCID: PMC9574636 DOI: 10.1098/rstb.2021.0252] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2022] [Accepted: 05/25/2022] [Indexed: 12/22/2022] Open
Abstract
The blastocyst is a conserved stage and distinct milestone in the development of the mammalian embryo. Blastocyst stage embryos comprise three cell lineages which arise through two sequential binary cell fate specification steps. In the first, extra-embryonic trophectoderm (TE) cells segregate from inner cell mass (ICM) cells. Subsequently, ICM cells acquire a pluripotent epiblast (Epi) or extra-embryonic primitive endoderm (PrE, also referred to as hypoblast) identity. In the mouse, nascent Epi and PrE cells emerge in a salt-and-pepper distribution in the early blastocyst and are subsequently sorted into adjacent tissue layers by the late blastocyst stage. Epi cells cluster at the interior of the ICM, while PrE cells are positioned on its surface interfacing the blastocyst cavity, where they display apicobasal polarity. As the embryo implants into the maternal uterus, cells at the periphery of the PrE epithelium, at the intersection with the TE, break away and migrate along the TE as they mature into parietal endoderm (ParE). PrE cells remaining in association with the Epi mature into visceral endoderm. In this review, we discuss our current understanding of the PrE from its specification to its maturation. This article is part of the theme issue 'Extraembryonic tissues: exploring concepts, definitions and functions across the animal kingdom'.
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Affiliation(s)
- Sayali Chowdhary
- Developmental Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
| | - Anna-Katerina Hadjantonakis
- Developmental Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
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8
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Portela M, Jimenez-Carretero D, Labrador V, Andreu MJ, Arza E, Caiolfa VR, Manzanares M. Chromatin dynamics through mouse preimplantation development revealed by single molecule localisation microscopy. Biol Open 2022; 11:275915. [PMID: 35876820 PMCID: PMC9346283 DOI: 10.1242/bio.059401] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2022] [Accepted: 06/30/2022] [Indexed: 01/07/2023] Open
Abstract
Most studies addressing chromatin behaviour during preimplantation development are based on biochemical assays that lack spatial and cell-specific information, crucial during early development. Here, we describe the changes in chromatin taking place at the transition from totipotency to lineage specification, by using direct stochastical optical reconstruction microscopy (dSTORM) in whole-mount embryos during the first stages of mouse development. Through the study of two post-translational modifications of Histone 3 related to active and repressed chromatin, H3K4me3 and H3K9me3 respectively, we obtained a time-course of chromatin states, showing spatial differences between cell types, related to their differentiation state. This analysis adds a new layer of information to previous biochemical studies and provides novel insight to current models of chromatin organisation during the first stages of development. SUMMARY: We have applied super-resolution microscopy to analyse changes in the state of chromatin during the first stages of mouse development, from the two-cell stage to the blastocyst.
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Affiliation(s)
- Marta Portela
- Centro de Biología Molecular Severo Ochoa, CSIC-UAM, Madrid 28049, Spain.,Centro Nacional de Investigaciones Cardiovasculares (CNIC), Madrid 28029, Spain
| | - Daniel Jimenez-Carretero
- Bioinformatics Unit, Centro Nacional de Investigaciones Cardiovasculares (CNIC), Madrid 28029, Spain
| | - Veronica Labrador
- Microscopy and Dynamic Imaging Unit, Centro Nacional de Investigaciones Cardiovasculares (CNIC), Madrid 28029, Spain
| | - Maria Jose Andreu
- Centro Nacional de Investigaciones Cardiovasculares (CNIC), Madrid 28029, Spain
| | - Elvira Arza
- Microscopy and Dynamic Imaging Unit, Centro Nacional de Investigaciones Cardiovasculares (CNIC), Madrid 28029, Spain
| | - Valeria R Caiolfa
- Microscopy and Dynamic Imaging Unit, Centro Nacional de Investigaciones Cardiovasculares (CNIC), Madrid 28029, Spain.,Center for Experimental Imaging, Ospedale San Raffaele, Milan 20132, Italy
| | - Miguel Manzanares
- Centro de Biología Molecular Severo Ochoa, CSIC-UAM, Madrid 28049, Spain.,Centro Nacional de Investigaciones Cardiovasculares (CNIC), Madrid 28029, Spain
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9
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Shao Y, Fu J. Engineering multiscale structural orders for high-fidelity embryoids and organoids. Cell Stem Cell 2022; 29:722-743. [PMID: 35523138 PMCID: PMC9097334 DOI: 10.1016/j.stem.2022.04.003] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Embryoids and organoids hold great promise for human biology and medicine. Herein, we discuss conceptual and technological frameworks useful for developing high-fidelity embryoids and organoids that display tissue- and organ-level phenotypes and functions, which are critically needed for decoding developmental programs and improving translational applications. Through dissecting the layers of inputs controlling mammalian embryogenesis, we review recent progress in reconstructing multiscale structural orders in embryoids and organoids. Bioengineering tools useful for multiscale, multimodal structural engineering of tissue- and organ-level cellular organization and microenvironment are also discussed to present integrative, bioengineering-directed approaches to achieve next-generation, high-fidelity embryoids and organoids.
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Affiliation(s)
- Yue Shao
- Institute of Biomechanics and Medical Engineering, Department of Engineering Mechanics, Tsinghua University, Beijing 100084, China; State Key Laboratory of Primate Biomedical Research, Institute of Primate Translational Medicine, Kunming University of Science and Technology, Kunming, Yunnan 650500, China.
| | - Jianping Fu
- Department of Mechanical Engineering, University of Michigan, Ann Arbor, MI 48109, USA; Department of Cell & Developmental Biology, University of Michigan Medical School, Ann Arbor, MI 48109, USA; Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI 48109, USA
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10
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Nelson CM. Mechanical Control of Cell Differentiation: Insights from the Early Embryo. Annu Rev Biomed Eng 2022; 24:307-322. [PMID: 35385680 DOI: 10.1146/annurev-bioeng-060418-052527] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Differentiation is the process by which a cell activates the expression of tissue-specific genes, downregulates the expression of potency markers, and acquires the phenotypic characteristics of its mature fate. The signals that regulate differentiation include biochemical and mechanical factors within the surrounding microenvironment. We describe recent breakthroughs in our understanding of the mechanical control mechanisms that regulate differentiation, with a specific emphasis on the differentiation events that build the early mouse embryo. Engineering approaches to reproducibly mimic the mechanical regulation of differentiation will permit new insights into early development and applications in regenerative medicine. Expected final online publication date for the Annual Review of Biomedical Engineering, Volume 24 is June 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.
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Affiliation(s)
- Celeste M Nelson
- Departments of Chemical & Biological Engineering and Molecular Biology, Princeton University, Princeton, New Jersey USA;
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11
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Zeng J, Liu N, Yang Y, Cheng Y, Li Y, Guo X, Luo Q, Zhu L, Guan H, Song B, Sun X. Pak2 reduction induces a failure of early embryonic development in mice. Reprod Biol Endocrinol 2021; 19:181. [PMID: 34879863 PMCID: PMC8656077 DOI: 10.1186/s12958-021-00865-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/27/2021] [Accepted: 11/28/2021] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND The quality of the early embryo is vital to embryonic development and implantation. As a highly conserved serine/threonine kinase, p21-activated kinase 2 (Pak2) participates in diverse biologic processes, especially in cytoskeleton remodeling and cell apoptosis. In mice, Pak2 knock out and endothelial depletion of Pak2 showed embryonic lethality. However, the role of Pak2 in preimplantation embryos remains unelucidated. METHODS In the present work, Pak2 was reduced using a specific small interfering RNA in early mouse embryos, validating the unique roles of Pak2 in spindle assembly and DNA repair during mice early embryonic development. We also employed immunoblotting, immunostaining, in vitro fertilization (IVF) and image quantification analyses to test the Pak2 knockdown on the embryonic development progression, spindle assembly, chromosome alignment, oxidative stress, DNA lesions and blastocyst cell apoptosis. Areas in chromatin with γH2AX were detected by immunofluorescence microscopy and serve as a biomarker of DNA damages. RESULTS We found that Pak2 knockdown significantly reduced blastocyst formation of early embryos. In addition, Pak2 reduction led to dramatically increased abnormal spindle assembly and chromosomal aberrations in the embryos. We noted the overproduction of reactive oxygen species (ROS) with Pak2 knockdown in embryos. In response to DNA double strand breaks (DSBs), the histone protein H2AX is specifically phosphorylated at serine139 to generate γH2AX, which is used to quantitative DSBs. In this research, Pak2 knockdown also resulted in the accumulation of phosphorylated γH2AX, indicative of increased embryonic DNA damage. Commensurate with this, a significantly augmented rate of blastocyst cell apoptosis was detected in Pak2-KD embryos compared to their controls. CONCLUSIONS Collectively, our data suggest that Pak2 may serve as an important regulator of spindle assembly and DNA repair, and thus participate in the development of early mouse embryos.
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Affiliation(s)
- Juan Zeng
- Department of Obstetrics and Gynecology, Key Laboratory for Major Obstetric Diseases of Guangdong Province, The Third Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong, China
- Key Laboratory of Reproduction and Genetics of Guangdong Higher Education Institutes, Guangzhou, Guangdong, China
| | - Nengqing Liu
- Department of Obstetrics and Gynecology, Key Laboratory for Major Obstetric Diseases of Guangdong Province, The Third Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong, China
- Key Laboratory of Reproduction and Genetics of Guangdong Higher Education Institutes, Guangzhou, Guangdong, China
| | - Yinghong Yang
- Department of Obstetrics and Gynecology, Key Laboratory for Major Obstetric Diseases of Guangdong Province, The Third Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong, China
- Key Laboratory of Reproduction and Genetics of Guangdong Higher Education Institutes, Guangzhou, Guangdong, China
| | - Yi Cheng
- Department of Obstetrics and Gynecology, Key Laboratory for Major Obstetric Diseases of Guangdong Province, The Third Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong, China
- Key Laboratory of Reproduction and Genetics of Guangdong Higher Education Institutes, Guangzhou, Guangdong, China
| | - Yuanshuai Li
- Department of Obstetrics and Gynecology, Key Laboratory for Major Obstetric Diseases of Guangdong Province, The Third Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong, China
- Key Laboratory of Reproduction and Genetics of Guangdong Higher Education Institutes, Guangzhou, Guangdong, China
| | - Xiaoxia Guo
- Department of Obstetrics and Gynecology, Key Laboratory for Major Obstetric Diseases of Guangdong Province, The Third Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong, China
- Key Laboratory of Reproduction and Genetics of Guangdong Higher Education Institutes, Guangzhou, Guangdong, China
| | - Qian Luo
- Department of Obstetrics and Gynecology, Key Laboratory for Major Obstetric Diseases of Guangdong Province, The Third Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong, China
- Key Laboratory of Reproduction and Genetics of Guangdong Higher Education Institutes, Guangzhou, Guangdong, China
| | - Lifen Zhu
- Department of Obstetrics and Gynecology, Key Laboratory for Major Obstetric Diseases of Guangdong Province, The Third Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong, China
- Key Laboratory of Reproduction and Genetics of Guangdong Higher Education Institutes, Guangzhou, Guangdong, China
| | - Hongmei Guan
- Department of Obstetrics and Gynecology, Key Laboratory for Major Obstetric Diseases of Guangdong Province, The Third Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong, China
- Key Laboratory of Reproduction and Genetics of Guangdong Higher Education Institutes, Guangzhou, Guangdong, China
| | - Bing Song
- Department of Obstetrics and Gynecology, Key Laboratory for Major Obstetric Diseases of Guangdong Province, The Third Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong, China
- Key Laboratory of Reproduction and Genetics of Guangdong Higher Education Institutes, Guangzhou, Guangdong, China
| | - Xiaofang Sun
- Department of Obstetrics and Gynecology, Key Laboratory for Major Obstetric Diseases of Guangdong Province, The Third Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong, China.
- Key Laboratory of Reproduction and Genetics of Guangdong Higher Education Institutes, Guangzhou, Guangdong, China.
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12
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Herrera-Delgado E, Maître JL. A theoretical understanding of mammalian preimplantation development. Cells Dev 2021; 168:203752. [PMID: 34634520 DOI: 10.1016/j.cdev.2021.203752] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2021] [Revised: 09/30/2021] [Accepted: 09/30/2021] [Indexed: 11/28/2022]
Abstract
The blastocyst has long been a hallmark system of study in developmental biology due to its importance in mammalian development and clinical relevance for assisted reproductive technologies. In recent years, the blastocyst is emerging as a system of study for mathematical modelling. In this review, we compile, to our knowledge, all models describing preimplantation development. Coupled with experiments, these models have provided insight regarding the morphogenesis and cell-fate specification throughout preimplantation development. In the case of cell-fate specification, theoretical models have provided mechanisms explaining how proportion of cell types are established and maintained when confronted to perturbations. For cell-shape based models, they have described quantitatively how mechanical forces sculpt the blastocyst and even predicted how morphogenesis could be manipulated. As theoretical biology develops, we believe the next critical stage in modelling involves an integration of cell fate and mechanics to provide integrative models of development at distinct spatiotemporal scales. We discuss how, building on a balanced base of mechanical and chemical models, the preimplantation embryo will play a key role in integrating these two faces of the same coin.
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Affiliation(s)
| | - Jean-Léon Maître
- Institut Curie, PSL Research University, CNRS UMR3215, INSERM U934, Paris, France.
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13
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Leahy BD, Racowsky C, Needleman D. Inferring simple but precise quantitative models of human oocyte and early embryo development. J R Soc Interface 2021; 18:20210475. [PMID: 34493094 PMCID: PMC8424348 DOI: 10.1098/rsif.2021.0475] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2021] [Accepted: 08/16/2021] [Indexed: 11/12/2022] Open
Abstract
Macroscopic, phenomenological models are useful as concise framings of our understandings in fields from statistical physics to finance to biology. Constructing a phenomenological model for development would provide a framework for understanding the complicated, regulatory nature of oogenesis and embryogenesis. Here, we use a data-driven approach to infer quantitative, precise models of human oocyte maturation and pre-implantation embryo development, by analysing clinical in-vitro fertilization (IVF) data on 7399 IVF cycles resulting in 57 827 embryos. Surprisingly, we find that both oocyte maturation and early embryo development are quantitatively described by simple models with minimal interactions. This simplicity suggests that oogenesis and embryogenesis are composed of modular processes that are relatively siloed from one another. In particular, our analysis provides strong evidence that (i) pre-antral follicles produce anti-Müllerian hormone independently of effects from other follicles, (ii) oocytes mature to metaphase-II independently of the woman's age, her BMI and other factors, (iii) early embryo development is memoryless for the variables assessed here, in that the probability of an embryo transitioning from its current developmental stage to the next is independent of its previous stage. Our results both provide insight into the fundamentals of oogenesis and embryogenesis and have implications for the clinical IVF.
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Affiliation(s)
- Brian D. Leahy
- Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA, USA
- SEAS, Harvard University, Cambridge, MA, USA
| | - Catherine Racowsky
- Brigham Women’s Hospital, Boston, MA, USA
- Harvard Medical School, Boston, MA, USA
| | - Daniel Needleman
- Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA, USA
- SEAS, Harvard University, Cambridge, MA, USA
- Center for Computational Biology, Flatiron Institute, New York, NY, USA
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14
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Clonal dynamics in early human embryogenesis inferred from somatic mutation. Nature 2021; 597:393-397. [PMID: 34433967 DOI: 10.1038/s41586-021-03786-8] [Citation(s) in RCA: 58] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2020] [Accepted: 06/29/2021] [Indexed: 12/19/2022]
Abstract
Cellular dynamics and fate decision in early human embryogenesis remain largely unknown owing to the challenges of performing studies in human embryos1. Here, we explored whole-genomes of 334 single-cell colonies and targeted deep sequences of 379 bulk tissues obtained from various anatomical locations of seven recently deceased adult human donors. Using somatic mutations as an intrinsic barcode, we reconstructed early cellular phylogenies that demonstrate (1) an endogenous mutational rate that is higher in the first cell division but decreases to approximately one per cell per cell division later in life; (2) universal unequal contribution of early cells to embryo proper, resulting from early cellular bottlenecks that stochastically set aside epiblast cells within the embryo; (3) examples of varying degrees of early clonal imbalances between tissues on the left and right sides of the body, different germ layers and specific anatomical parts and organs; (4) emergence of a few ancestral cells that will substantially contribute to adult cell pools in blood and liver; and (5) presence of mitochondrial DNA heteroplasmy in the fertilized egg. Our approach also provides insights into the age-related mutational processes and loss of sex chromosomes in normal somatic cells. In sum, this study provides a foundation for future studies to complete cellular phylogenies in human embryogenesis.
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15
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Duran-Nebreda S, Pla J, Vidiella B, Piñero J, Conde-Pueyo N, Solé R. Synthetic Lateral Inhibition in Periodic Pattern Forming Microbial Colonies. ACS Synth Biol 2021; 10:277-285. [PMID: 33449631 PMCID: PMC8486170 DOI: 10.1021/acssynbio.0c00318] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Multicellular entities are characterized by intricate spatial patterns, intimately related to the functions they perform. These patterns are often created from isotropic embryonic structures, without external information cues guiding the symmetry breaking process. Mature biological structures also display characteristic scales with repeating distributions of signals or chemical species across space. Many candidate patterning modules have been used to explain processes during development and typically include a set of interacting and diffusing chemicals or agents known as morphogens. Great effort has been put forward to better understand the conditions in which pattern-forming processes can occur in the biological domain. However, evidence and practical knowledge allowing us to engineer symmetry-breaking is still lacking. Here we follow a different approach by designing a synthetic gene circuit in E. coli that implements a local activation long-range inhibition mechanism. The synthetic gene network implements an artificial differentiation process that changes the physicochemical properties of the agents. Using both experimental results and modeling, we show that the proposed system is capable of symmetry-breaking leading to regular spatial patterns during colony growth. Studying how these patterns emerge is fundamental to further our understanding of the evolution of biocomplexity and the role played by self-organization. The artificial system studied here and the engineering perspective on embryogenic processes can help validate developmental theories and identify universal properties underpinning biological pattern formation, with special interest for the area of synthetic developmental biology.
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Affiliation(s)
- Salva Duran-Nebreda
- Institut de Biologia Evolutiva (CSIC-UPF), 08003 Barcelona, Spain
- ICREA-Complex Systems Lab, Universitat Pompeu Fabra, 08003 Barcelona, Spain
- Evolution of Technology Lab, Institut de Biologia Evolutiva (CSIC-UPF), 08003 Barcelona, Spain
| | - Jordi Pla
- Institut de Biologia Evolutiva (CSIC-UPF), 08003 Barcelona, Spain
- ICREA-Complex Systems Lab, Universitat Pompeu Fabra, 08003 Barcelona, Spain
| | - Blai Vidiella
- Institut de Biologia Evolutiva (CSIC-UPF), 08003 Barcelona, Spain
- ICREA-Complex Systems Lab, Universitat Pompeu Fabra, 08003 Barcelona, Spain
| | - Jordi Piñero
- Institut de Biologia Evolutiva (CSIC-UPF), 08003 Barcelona, Spain
- ICREA-Complex Systems Lab, Universitat Pompeu Fabra, 08003 Barcelona, Spain
| | - Nuria Conde-Pueyo
- Institut de Biologia Evolutiva (CSIC-UPF), 08003 Barcelona, Spain
- ICREA-Complex Systems Lab, Universitat Pompeu Fabra, 08003 Barcelona, Spain
| | - Ricard Solé
- Institut de Biologia Evolutiva (CSIC-UPF), 08003 Barcelona, Spain
- ICREA-Complex Systems Lab, Universitat Pompeu Fabra, 08003 Barcelona, Spain
- Santa Fe Institute, 1399 Hyde Park Road, Santa Fe, New Mexico 87501, United States
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16
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Sharma J, Antenos M, Madan P. A Comparative Analysis of Hippo Signaling Pathway Components during Murine and Bovine Early Mammalian Embryogenesis. Genes (Basel) 2021; 12:281. [PMID: 33669396 PMCID: PMC7920285 DOI: 10.3390/genes12020281] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2020] [Revised: 02/08/2021] [Accepted: 02/12/2021] [Indexed: 12/20/2022] Open
Abstract
The time required for successful blastocyst formation varies among multiple species. The formation of a blastocyst is governed by numerous molecular cell signaling pathways, such as the Hippo signaling pathway. The Hippo signaling pathway is initiated by increased cell-cell contact and via apical polarity proteins (AMOT, PARD6, and NF2) during the period of preimplantation embryogenesis. Cell-cell contact and cell polarity activate (phosphorylates) the core cascade components of the pathway (mammalian sterile twenty like 1 and 2 (MST1/2) and large tumor suppressor 1 and 2 (LATS1/2)), which in turn phosphorylate the downstream effectors of the pathway (YAP1/TAZ). The Hippo pathway remains inactive with YAP1 (Yes Associated protein 1) present inside the nucleus in the trophectoderm (TE) cells (polar blastomeres) of the mouse blastocyst. In the inner cell mass (ICM) cells (apolar blastomeres), the pathway is activated with p-YAP1 present in the cytoplasm. On the contrary, during bovine embryogenesis, p-YAP1 is exclusively present in the nucleus in both TE and ICM cells. Contrary to mouse embryos, transcription co activator with PDZ-binding motif (TAZ) (also known as WWTR1) is also predominantly present in the cytoplasm in all the blastomeres during bovine embryogenesis. This review outlines the major differences in the localization and function of Hippo signaling pathway components of murine and bovine preimplantation embryos, suggesting significant differences in the regulation of this pathway in between the two species. The variance observed in the Hippo signaling pathway between murine and bovine embryos confirms that both of these early embryonic models are quite distinct. Moreover, based on the similarity of the Hippo signaling pathway between bovine and human early embryo development, bovine embryos could be an alternate model for understanding the regulation of the Hippo signaling pathway in human embryos.
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Affiliation(s)
| | | | - Pavneesh Madan
- Department of Biomedical Sciences, University of Guelph, Guelph, ON N1G 2W1, Canada; (J.S.); (M.A.)
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17
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Fu J, Warmflash A, Lutolf MP. Stem-cell-based embryo models for fundamental research and translation. NATURE MATERIALS 2021; 20:132-144. [PMID: 33199861 PMCID: PMC7855549 DOI: 10.1038/s41563-020-00829-9] [Citation(s) in RCA: 78] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Accepted: 09/14/2020] [Indexed: 06/01/2023]
Abstract
Despite its importance, understanding the early phases of human development has been limited by availability of human samples. The recent emergence of stem-cell-derived embryo models, a new field aiming to use stem cells to construct in vitro models to recapitulate snapshots of the development of the mammalian conceptus, opens up exciting opportunities to promote fundamental understanding of human development and advance reproductive and regenerative medicine. This Review provides a summary of the current knowledge of early mammalian development, using mouse and human conceptuses as models, and emphasizes their similarities and critical differences. We then highlight existing embryo models that mimic different aspects of mouse and human development. We further discuss bioengineering tools used for controlling multicellular interactions and self-organization critical for the development of these models. We conclude with a discussion of the important next steps and exciting future opportunities of stem-cell-derived embryo models for fundamental discovery and translation.
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Affiliation(s)
- Jianping Fu
- Department of Mechanical Engineering, University of Michigan, Ann Arbor, MI, USA.
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, USA.
- Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, MI, USA.
| | - Aryeh Warmflash
- Department of Biosciences, Rice University, Houston, TX, USA.
- Department of Bioengineering, Rice University, Houston, TX, USA.
| | - Matthias P Lutolf
- Laboratory of Stem Cell Bioengineering, Institute of Bioengineering, School of Life Sciences and School of Engineering, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland.
- Institute of Chemical Sciences and Engineering, School of Basic Science, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland.
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18
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Fiorentino J, Torres-Padilla ME, Scialdone A. Measuring and Modeling Single-Cell Heterogeneity and Fate Decision in Mouse Embryos. Annu Rev Genet 2020; 54:167-187. [PMID: 32867543 DOI: 10.1146/annurev-genet-021920-110200] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Cellular heterogeneity is a property of any living system; however, its relationship with cellular fate decision remains an open question. Recent technological advances have enabled valuable insights, especially in complex systems such as the mouse embryo. In this review, we discuss recent studies that characterize cellular heterogeneity at different levels during mouse development, from the two-cell stage up to gastrulation. In addition to key experimental findings, we review mathematical modeling approaches that help researchers interpret these findings. Disentangling the role of heterogeneity in cell fate decision will likely rely on the refined integration of experiments, large-scale omics data, and mathematical modeling, complemented by the use of synthetic embryos and gastruloids as promising in vitro models.
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Affiliation(s)
- Jonathan Fiorentino
- Institute of Epigenetics and Stem Cells (IES), Helmholtz Zentrum München, D-81377 München, Germany; .,Institute of Functional Epigenetics (IFE) and Institute of Computational Biology (ICB), Helmholtz Zentrum München, D-85764 Neuherberg, Germany
| | - Maria-Elena Torres-Padilla
- Institute of Epigenetics and Stem Cells (IES), Helmholtz Zentrum München, D-81377 München, Germany; .,Faculty of Biology, Ludwig-Maximilians Universität, D-82152 Planegg-Martinsried, Germany
| | - Antonio Scialdone
- Institute of Epigenetics and Stem Cells (IES), Helmholtz Zentrum München, D-81377 München, Germany; .,Institute of Functional Epigenetics (IFE) and Institute of Computational Biology (ICB), Helmholtz Zentrum München, D-85764 Neuherberg, Germany
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19
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Leonavicius K, Royer C, Miranda AMA, Tyser RCV, Kip A, Srinivas S. Spatial protein analysis in developing tissues: a sampling-based image processing approach. Philos Trans R Soc Lond B Biol Sci 2020; 375:20190560. [PMID: 32829691 PMCID: PMC7482225 DOI: 10.1098/rstb.2019.0560] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/22/2020] [Indexed: 11/19/2022] Open
Abstract
Advances in fluorescence microscopy approaches have made it relatively easy to generate multi-dimensional image volumes and have highlighted the need for flexible image analysis tools for the extraction of quantitative information from such data. Here we demonstrate that by focusing on simplified feature-based nuclear segmentation and probabilistic cytoplasmic detection we can create a tool that is able to extract geometry-based information from diverse mammalian tissue images. Our open-source image analysis platform, called 'SilentMark', can cope with three-dimensional noisy images and with crowded fields of cells to quantify signal intensity in different cellular compartments. Additionally, it provides tissue geometry related information, which allows one to quantify protein distribution with respect to marked regions of interest. The lightweight SilentMark algorithms have the advantage of not requiring multiple processors, graphics cards or training datasets and can be run even with just several hundred megabytes of memory. This makes it possible to use the method as a Web application, effectively eliminating setup hurdles and compatibility issues with operating systems. We test this platform on mouse pre-implantation embryos, embryonic stem cell-derived embryoid bodies and mouse embryonic heart, and relate protein localization to tissue geometry. This article is part of a discussion meeting issue 'Contemporary morphogenesis'.
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20
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Toralova T, Kinterova V, Chmelikova E, Kanka J. The neglected part of early embryonic development: maternal protein degradation. Cell Mol Life Sci 2020; 77:3177-3194. [PMID: 32095869 PMCID: PMC11104927 DOI: 10.1007/s00018-020-03482-2] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2019] [Revised: 01/24/2020] [Accepted: 02/07/2020] [Indexed: 12/28/2022]
Abstract
The degradation of maternally provided molecules is a very important process during early embryogenesis. However, the vast majority of studies deals with mRNA degradation and protein degradation is only a very little explored process yet. The aim of this article was to summarize current knowledge about the protein degradation during embryogenesis of mammals. In addition to resuming of known data concerning mammalian embryogenesis, we tried to fill the gaps in knowledge by comparison with facts known about protein degradation in early embryos of non-mammalian species. Maternal protein degradation seems to be driven by very strict rules in terms of specificity and timing. The degradation of some maternal proteins is certainly necessary for the normal course of embryonic genome activation (EGA) and several concrete proteins that need to be degraded before major EGA have been already found. Nevertheless, the most important period seems to take place even before preimplantation development-during oocyte maturation. The defects arisen during this period seems to be later irreparable.
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Affiliation(s)
- Tereza Toralova
- Laboratory of Developmental Biology, Institute of Animal Physiology and Genetics of the Czech Academy of Sciences, Libechov, Czech Republic
| | - Veronika Kinterova
- Laboratory of Developmental Biology, Institute of Animal Physiology and Genetics of the Czech Academy of Sciences, Libechov, Czech Republic.
- Department of Veterinary Sciences, Czech University of Life Sciences in Prague, Prague, Czech Republic.
| | - Eva Chmelikova
- Department of Veterinary Sciences, Czech University of Life Sciences in Prague, Prague, Czech Republic
| | - Jiri Kanka
- Laboratory of Developmental Biology, Institute of Animal Physiology and Genetics of the Czech Academy of Sciences, Libechov, Czech Republic
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21
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Płusa B, Piliszek A. Common principles of early mammalian embryo self-organisation. Development 2020; 147:147/14/dev183079. [PMID: 32699138 DOI: 10.1242/dev.183079] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Pre-implantation mammalian development unites extreme plasticity with a robust outcome: the formation of a blastocyst, an organised multi-layered structure ready for implantation. The process of blastocyst formation is one of the best-known examples of self-organisation. The first three cell lineages in mammalian development specify and arrange themselves during the morphogenic process based on cell-cell interactions. Despite decades of research, the unifying principles driving early mammalian development are still not fully defined. Here, we discuss the role of physical forces, and molecular and cellular mechanisms, in driving self-organisation and lineage formation that are shared between eutherian mammals.
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Affiliation(s)
- Berenika Płusa
- Faculty of Biology, Medicine and Health (FBMH), Division of Developmental Biology & Medicine, University of Manchester, Michael Smith Building, Oxford Road, Manchester, M13 9PT, UK
| | - Anna Piliszek
- Department of Experimental Embryology, Institute of Genetics and Animal Biotechnology, Polish Academy of Sciences, Jastrzebiec, Postepu 36A, 05-552 Magdalenka, Poland
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22
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Takahashi T, Shiraishi A. Stem Cell Signaling Pathways in the Small Intestine. Int J Mol Sci 2020; 21:ijms21062032. [PMID: 32188141 PMCID: PMC7139586 DOI: 10.3390/ijms21062032] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2020] [Revised: 03/06/2020] [Accepted: 03/09/2020] [Indexed: 12/20/2022] Open
Abstract
The ability of stem cells to divide and differentiate is necessary for tissue repair and homeostasis. Appropriate spatial and temporal mechanisms are needed. Local intercellular signaling increases expression of specific genes that mediate and maintain differentiation. Diffusible signaling molecules provide concentration-dependent induction of specific patterns of cell types or regions. Differentiation of adjacent cells, on the other hand, requires cell–cell contact and subsequent signaling. These two types of signals work together to allow stem cells to provide what organisms require. The ability to grow organoids has increased our understanding of the cellular and molecular features of small “niches” that modulate stem cell function in various organs, including the small intestine.
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23
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Vukic M, Wu H, Daxinger L. Making headway towards understanding how epigenetic mechanisms contribute to early-life effects. Philos Trans R Soc Lond B Biol Sci 2020; 374:20180126. [PMID: 30966890 DOI: 10.1098/rstb.2018.0126] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
It has become clear that in addition to the DNA sequence there is another layer of information, termed epigenetic modifications, that can influence phenotypes and traits. In particular, environmental epigenomics, which addresses the effect of the environment on the epigenome and human health, is becoming an area of great interest for many researchers working in different scientific fields. In this review, we will consider the current evidence that early-life environmental signals can have long-term effects on the epigenome. We will further evaluate how recent technological advances may enable us to unravel the molecular mechanisms underlying these phenomena, which will be crucial for understanding heritability in health and disease. This article is part of the theme issue 'Developing differences: early-life effects and evolutionary medicine'.
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Affiliation(s)
- Maja Vukic
- Department of Human Genetics, Leiden University Medical Centre , Einthovenweg 20, 2333 ZC Leiden , The Netherlands
| | - Haoyu Wu
- Department of Human Genetics, Leiden University Medical Centre , Einthovenweg 20, 2333 ZC Leiden , The Netherlands
| | - Lucia Daxinger
- Department of Human Genetics, Leiden University Medical Centre , Einthovenweg 20, 2333 ZC Leiden , The Netherlands
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24
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ROCK and RHO Playlist for Preimplantation Development: Streaming to HIPPO Pathway and Apicobasal Polarity in the First Cell Differentiation. ADVANCES IN ANATOMY EMBRYOLOGY AND CELL BIOLOGY 2020; 229:47-68. [PMID: 29177764 DOI: 10.1007/978-3-319-63187-5_5] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
In placental mammalian development, the first cell differentiation produces two distinct lineages that emerge according to their position within the embryo: the trophectoderm (TE, placenta precursor) differentiates in the surface, while the inner cell mass (ICM, fetal body precursor) forms inside. Here, we discuss how such position-dependent lineage specifications are regulated by the RHOA subfamily of small GTPases and RHO-associated coiled-coil kinases (ROCK). Recent studies in mouse show that activities of RHO/ROCK are required to promote TE differentiation and to concomitantly suppress ICM formation. RHO/ROCK operate through the HIPPO signaling pathway, whose cell position-specific modulation is central to establishing unique gene expression profiles that confer cell fate. In particular, activities of RHO/ROCK are essential in outside cells to promote nuclear localization of transcriptional co-activators YAP/TAZ, the downstream effectors of HIPPO signaling. Nuclear localization of YAP/TAZ depends on the formation of apicobasal polarity in outside cells, which requires activities of RHO/ROCK. We propose models of how RHO/ROCK regulate lineage specification and lay out challenges for future investigations to deepen our understanding of the roles of RHO/ROCK in preimplantation development. Finally, as RHO/ROCK may be inhibited by certain pharmacological agents, we discuss their potential impact on human preimplantation development in relation to fertility preservation in women.
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25
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Bai L, Yang L, Zhao C, Song L, Liu X, Bai C, Su G, Wei Z, Li G. Histone Demethylase UTX is an Essential Factor for Zygotic Genome Activation and Regulates Zscan4 Expression in Mouse Embryos. Int J Biol Sci 2019; 15:2363-2372. [PMID: 31595154 PMCID: PMC6775313 DOI: 10.7150/ijbs.34635] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2019] [Accepted: 07/28/2019] [Indexed: 01/05/2023] Open
Abstract
Following fertilization, the zygotic genome is activated through a process termed zygotic genome activation (ZGA), which enables zygotic gene products to replace the maternal products and initiates early embryonic development. During the ZGA period, the embryonic epigenome experiences extensive recodifications. The H3K27me3 demethylase UTX is essential for post-implantation embryonic development. However, it remains unclear whether UTX participates in preimplantation development, especially during the ZGA process. In the present study, we showed that either knockdown or overexpression of UTX led to embryonic development retardation, whereas simultaneous depletion of UTX and overexpression of ZSCAN4D rescued the embryonic development, indicating that UTX positively regulated Zscan4d expression. Using a transgenic mice model, we also found that UTX was required for preimplantation embryonic development. In conclusion, these results indicate that UTX functions as a novel regulator and plays critical roles during ZGA in addition to early embryonic development.
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Affiliation(s)
- Lige Bai
- State Key Laboratory of Reproductive Regulation and Breeding of Grassland Livestock (R2BGL), Inner Mongolia University, Hohhot, China.,College of Life Sciences, Inner Mongolia University, Hohhot, China
| | - Lei Yang
- State Key Laboratory of Reproductive Regulation and Breeding of Grassland Livestock (R2BGL), Inner Mongolia University, Hohhot, China
| | - Caiquan Zhao
- State Key Laboratory of Reproductive Regulation and Breeding of Grassland Livestock (R2BGL), Inner Mongolia University, Hohhot, China.,College of Life Sciences, Inner Mongolia University, Hohhot, China
| | - Lishuang Song
- State Key Laboratory of Reproductive Regulation and Breeding of Grassland Livestock (R2BGL), Inner Mongolia University, Hohhot, China.,College of Life Sciences, Inner Mongolia University, Hohhot, China
| | - Xuefei Liu
- State Key Laboratory of Reproductive Regulation and Breeding of Grassland Livestock (R2BGL), Inner Mongolia University, Hohhot, China
| | - Chunling Bai
- State Key Laboratory of Reproductive Regulation and Breeding of Grassland Livestock (R2BGL), Inner Mongolia University, Hohhot, China.,College of Life Sciences, Inner Mongolia University, Hohhot, China
| | - Guanghua Su
- State Key Laboratory of Reproductive Regulation and Breeding of Grassland Livestock (R2BGL), Inner Mongolia University, Hohhot, China.,College of Life Sciences, Inner Mongolia University, Hohhot, China
| | - Zhuying Wei
- State Key Laboratory of Reproductive Regulation and Breeding of Grassland Livestock (R2BGL), Inner Mongolia University, Hohhot, China.,College of Life Sciences, Inner Mongolia University, Hohhot, China
| | - Guangpeng Li
- State Key Laboratory of Reproductive Regulation and Breeding of Grassland Livestock (R2BGL), Inner Mongolia University, Hohhot, China.,College of Life Sciences, Inner Mongolia University, Hohhot, China
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26
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Roberts RM, Ezashi T, Sheridan MA, Yang Y. Specification of trophoblast from embryonic stem cells exposed to BMP4. Biol Reprod 2019; 99:212-224. [PMID: 29579154 DOI: 10.1093/biolre/ioy070] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2017] [Accepted: 03/21/2018] [Indexed: 01/16/2023] Open
Abstract
Trophoblast (TB) comprises the outer cell layers of the mammalian placenta that make direct contact with the maternal uterus and, in species with a highly invasive placenta, maternal blood. It has its origin as trophectoderm, a single epithelial layer of extra-embryonic ectoderm that surrounds the embryo proper at the blastocyst stage of development. Here, we briefly compare the features of TB specification and determination in the mouse and the human. We then review research on a model system that has been increasingly employed to study TB emergence, namely the BMP4 (bone morphogenetic protein-4)-directed differentiation of human embryonic stem cells (ESCd), and discuss why outcomes using it have proved so uneven. We also examine the controversial aspects of this model, particularly the issue of whether or not the ESCd represents TB at all. Our focus here has been to explore similarities and potential differences between the phenotypes of ESCd, trophectoderm, placental villous TB, and human TB stem cells. We then explore the role of BMP4 in the differentiation of human pluripotent cells to TB and suggest that it converts the ESC into a totipotent state that is primed for TB differentiation when self-renewal is blocked. Finally we speculate that the TB formed from ESC is homologous to the trophectoderm-derived, invasive TB that envelopes the implanting conceptus during the second week of pregnancy.
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Affiliation(s)
- R Michael Roberts
- Bond Life Sciences Center, University of Missouri, Columbia, Missouri, USA.,Department of Biochemistry, University of Missouri, Columbia, Missouri, USA.,Division of Animal Sciences, University of Missouri, Columbia, Missouri, USA
| | - Toshihiko Ezashi
- Bond Life Sciences Center, University of Missouri, Columbia, Missouri, USA.,Division of Animal Sciences, University of Missouri, Columbia, Missouri, USA
| | - Megan A Sheridan
- Bond Life Sciences Center, University of Missouri, Columbia, Missouri, USA.,Department of Biochemistry, University of Missouri, Columbia, Missouri, USA
| | - Ying Yang
- Department of Molecular Pharmacology and Physiology, University of South Florida, Tampa, Florida, USA
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27
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Shparberg RA, Glover HJ, Morris MB. Modeling Mammalian Commitment to the Neural Lineage Using Embryos and Embryonic Stem Cells. Front Physiol 2019; 10:705. [PMID: 31354503 PMCID: PMC6637848 DOI: 10.3389/fphys.2019.00705] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2019] [Accepted: 05/20/2019] [Indexed: 12/21/2022] Open
Abstract
Early mammalian embryogenesis relies on a large range of cellular and molecular mechanisms to guide cell fate. In this highly complex interacting system, molecular circuitry tightly controls emergent properties, including cell differentiation, proliferation, morphology, migration, and communication. These molecular circuits include those responsible for the control of gene and protein expression, as well as metabolism and epigenetics. Due to the complexity of this circuitry and the relative inaccessibility of the mammalian embryo in utero, mammalian neural commitment remains one of the most challenging and poorly understood areas of developmental biology. In order to generate the nervous system, the embryo first produces two pluripotent populations, the inner cell mass and then the primitive ectoderm. The latter is the cellular substrate for gastrulation from which the three multipotent germ layers form. The germ layer definitive ectoderm, in turn, is the substrate for multipotent neurectoderm (neural plate and neural tube) formation, representing the first morphological signs of nervous system development. Subsequent patterning of the neural tube is then responsible for the formation of most of the central and peripheral nervous systems. While a large number of studies have assessed how a competent neurectoderm produces mature neural cells, less is known about the molecular signatures of definitive ectoderm and neurectoderm and the key molecular mechanisms driving their formation. Using pluripotent stem cells as a model, we will discuss the current understanding of how the pluripotent inner cell mass transitions to pluripotent primitive ectoderm and sequentially to the multipotent definitive ectoderm and neurectoderm. We will focus on the integration of cell signaling, gene activation, and epigenetic control that govern these developmental steps, and provide insight into the novel growth factor-like role that specific amino acids, such as L-proline, play in this process.
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Affiliation(s)
| | | | - Michael B. Morris
- Embryonic Stem Cell Laboratory, Discipline of Physiology, School of Medical Sciences, Bosch Institute, University of Sydney, Sydney, NSW, Australia
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28
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Hydraulic control of mammalian embryo size and cell fate. Nature 2019; 571:112-116. [PMID: 31189957 DOI: 10.1038/s41586-019-1309-x] [Citation(s) in RCA: 174] [Impact Index Per Article: 34.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2018] [Accepted: 05/21/2019] [Indexed: 11/08/2022]
Abstract
Size control is fundamental in tissue development and homeostasis1,2. Although the role of cell proliferation in these processes has been widely studied, the mechanisms that control embryo size-and how these mechanisms affect cell fate-remain unknown. Here we use the mouse blastocyst as a model to unravel a key role of fluid-filled lumen in the control of embryo size and specification of cell fate. We find that there is a twofold increase in lumenal pressure during blastocyst development, which translates into a concomitant increase in cell cortical tension and tissue stiffness of the trophectoderm that lines the lumen. Increased cortical tension leads to vinculin mechanosensing and maturation of functional tight junctions, which establishes a positive feedback loop to accommodate lumen growth. When the cortical tension reaches a critical threshold, cell-cell adhesion cannot be sustained during mitotic entry, which leads to trophectoderm rupture and blastocyst collapse. A simple theory of hydraulically gated oscillations recapitulates the observed dynamics of size oscillations, and predicts the scaling of embryo size with tissue volume. This theory further predicts that disrupted tight junctions or increased tissue stiffness lead to a smaller embryo size, which we verified by biophysical, embryological, pharmacological and genetic perturbations. Changes in lumenal pressure and size can influence the cell division pattern of the trophectoderm, and thereby affect cell allocation and fate. Our study reveals how lumenal pressure and tissue mechanics control embryo size at the tissue scale, which is coupled to cell position and fate at the cellular scale.
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Serra D, Mayr U, Boni A, Lukonin I, Rempfler M, Challet Meylan L, Stadler MB, Strnad P, Papasaikas P, Vischi D, Waldt A, Roma G, Liberali P. Self-organization and symmetry breaking in intestinal organoid development. Nature 2019; 569:66-72. [PMID: 31019299 PMCID: PMC6544541 DOI: 10.1038/s41586-019-1146-y] [Citation(s) in RCA: 297] [Impact Index Per Article: 59.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2018] [Accepted: 03/27/2019] [Indexed: 01/08/2023]
Abstract
Intestinal organoids are complex three-dimensional structures that mimic the cell type composition and tissue organization of the intestine by recapitulating the self-organizing ability of cell populations derived from a single intestinal stem cell. Crucial in this process is a first symmetry-breaking event, in which only a fraction of identical cells in a symmetrical sphere differentiate into Paneth cells, which generate the stem cell niche and lead to asymmetric structures such as crypts and villi. We here combine single-cell quantitative genomic and imaging approaches to characterize the development of intestinal organoids from single cells. We show that their development follows a regeneration process driven by transient Yap1 activation. Cell-to-cell variability in Yap1, emerging in symmetrical spheres, initiates a Notch/Dll1 activation driving the symmetry-breaking event and the formation of the first Paneth cell. Our findings reveal how single cells exposed to a uniform growth-promoting environment have the intrinsic ability to generate emergent, self-organized behavior resulting in the formation of complex multicellular asymmetric structures.
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Affiliation(s)
- Denise Serra
- Friedrich Miescher Institute for Biomedical Research (FMI), Basel, Switzerland.,University of Basel, Basel, Switzerland
| | - Urs Mayr
- Friedrich Miescher Institute for Biomedical Research (FMI), Basel, Switzerland.,University of Basel, Basel, Switzerland
| | - Andrea Boni
- Friedrich Miescher Institute for Biomedical Research (FMI), Basel, Switzerland.,Viventis Microscopy Sàrl, EPFL Innovation Park, Lausanne, Switzerland
| | - Ilya Lukonin
- Friedrich Miescher Institute for Biomedical Research (FMI), Basel, Switzerland.,University of Basel, Basel, Switzerland
| | - Markus Rempfler
- Friedrich Miescher Institute for Biomedical Research (FMI), Basel, Switzerland
| | | | - Michael B Stadler
- Friedrich Miescher Institute for Biomedical Research (FMI), Basel, Switzerland.,Swiss Institute of Bioinformatics, Basel, Switzerland
| | - Petr Strnad
- Friedrich Miescher Institute for Biomedical Research (FMI), Basel, Switzerland.,Viventis Microscopy Sàrl, EPFL Innovation Park, Lausanne, Switzerland
| | - Panagiotis Papasaikas
- Friedrich Miescher Institute for Biomedical Research (FMI), Basel, Switzerland.,Swiss Institute of Bioinformatics, Basel, Switzerland
| | - Dario Vischi
- Friedrich Miescher Institute for Biomedical Research (FMI), Basel, Switzerland
| | - Annick Waldt
- Novartis Institutes for BioMedical Research, Novartis Pharma AG, Basel, Switzerland
| | - Guglielmo Roma
- Novartis Institutes for BioMedical Research, Novartis Pharma AG, Basel, Switzerland
| | - Prisca Liberali
- Friedrich Miescher Institute for Biomedical Research (FMI), Basel, Switzerland. .,University of Basel, Basel, Switzerland.
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Silva TP, Cotovio JP, Bekman E, Carmo-Fonseca M, Cabral JMS, Fernandes TG. Design Principles for Pluripotent Stem Cell-Derived Organoid Engineering. Stem Cells Int 2019; 2019:4508470. [PMID: 31149014 PMCID: PMC6501244 DOI: 10.1155/2019/4508470] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2018] [Revised: 02/12/2019] [Accepted: 02/24/2019] [Indexed: 12/17/2022] Open
Abstract
Human morphogenesis is a complex process involving distinct microenvironmental and physical signals that are manipulated in space and time to give rise to complex tissues and organs. Advances in pluripotent stem cell (PSC) technology have promoted the in vitro recreation of processes involved in human morphogenesis. The development of organoids from human PSCs represents one reliable source for modeling a large spectrum of human disorders, as well as a promising approach for drug screening and toxicological tests. Based on the "self-organization" capacity of stem cells, different PSC-derived organoids have been created; however, considerable differences between in vitro-generated PSC-derived organoids and their in vivo counterparts have been reported. Advances in the bioengineering field have allowed the manipulation of different components, including cellular and noncellular factors, to better mimic the in vivo microenvironment. In this review, we focus on different examples of bioengineering approaches used to promote the self-organization of stem cells, including assembly, patterning, and morphogenesis in vitro, contributing to tissue-like structure formation.
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Affiliation(s)
- Teresa P. Silva
- Department of Bioengineering and iBB-Institute for Bioengineering and Biosciences, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisboa, Portugal
- The Discoveries Centre for Regenerative and Precision Medicine, Lisbon Campus, Universidade de Lisboa, Lisboa, Portugal
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Av Prof Egas Moniz, Edificio Egas Moniz, 1649-028 Lisboa, Portugal
| | - João P. Cotovio
- Department of Bioengineering and iBB-Institute for Bioengineering and Biosciences, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisboa, Portugal
- The Discoveries Centre for Regenerative and Precision Medicine, Lisbon Campus, Universidade de Lisboa, Lisboa, Portugal
| | - Evguenia Bekman
- Department of Bioengineering and iBB-Institute for Bioengineering and Biosciences, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisboa, Portugal
- The Discoveries Centre for Regenerative and Precision Medicine, Lisbon Campus, Universidade de Lisboa, Lisboa, Portugal
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Av Prof Egas Moniz, Edificio Egas Moniz, 1649-028 Lisboa, Portugal
| | - Maria Carmo-Fonseca
- The Discoveries Centre for Regenerative and Precision Medicine, Lisbon Campus, Universidade de Lisboa, Lisboa, Portugal
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Av Prof Egas Moniz, Edificio Egas Moniz, 1649-028 Lisboa, Portugal
| | - Joaquim M. S. Cabral
- Department of Bioengineering and iBB-Institute for Bioengineering and Biosciences, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisboa, Portugal
- The Discoveries Centre for Regenerative and Precision Medicine, Lisbon Campus, Universidade de Lisboa, Lisboa, Portugal
| | - Tiago G. Fernandes
- Department of Bioengineering and iBB-Institute for Bioengineering and Biosciences, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisboa, Portugal
- The Discoveries Centre for Regenerative and Precision Medicine, Lisbon Campus, Universidade de Lisboa, Lisboa, Portugal
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Menchero S, Rollan I, Lopez-Izquierdo A, Andreu MJ, Sainz de Aja J, Kang M, Adan J, Benedito R, Rayon T, Hadjantonakis AK, Manzanares M. Transitions in cell potency during early mouse development are driven by Notch. eLife 2019; 8:42930. [PMID: 30958266 PMCID: PMC6486152 DOI: 10.7554/elife.42930] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2018] [Accepted: 04/07/2019] [Indexed: 12/11/2022] Open
Abstract
The Notch signalling pathway plays fundamental roles in diverse developmental processes in metazoans, where it is important in driving cell fate and directing differentiation of various cell types. However, we still have limited knowledge about the role of Notch in early preimplantation stages of mammalian development, or how it interacts with other signalling pathways active at these stages such as Hippo. By using genetic and pharmacological tools in vivo, together with image analysis of single embryos and pluripotent cell culture, we have found that Notch is active from the 4-cell stage. Transcriptomic analysis in single morula identified novel Notch targets, such as early naïve pluripotency markers or transcriptional repressors such as TLE4. Our results reveal a previously undescribed role for Notch in driving transitions during the gradual loss of potency that takes place in the early mouse embryo prior to the first lineage decisions. We start life as a single cell, which immediately begins to divide to form an embryo that will eventually contain all the different kinds of cells found in the adult body. During the first few rounds of cell division, embryonic cells can become any type of adult cells, but also form the placenta, the organ that sustains the embryo while in the womb. As cells keep on dividing, they lose this ability, called potency, and they take on more specific and inflexible roles. The first choice embryonic cells must make is whether to become part of the placenta or part of the future body. These types of decisions are controlled by molecular cascades known as signalling pathways, which relay information from the cells surface to its control centre. There, specific genes get turned on or off in response to an outside signal. Previous research showed that two signalling pathways, Hippo and Notch, help separate placenta cells from those that will form the rest of the body. However, it was not known whether the two pathways worked independently, or if they were overlapping. Menchero et al. therefore wanted to find out when exactly the Notch pathway started to be active, and examine how it helped cells to either become the placenta or part of the future body. Experiments with developing mouse embryos showed that the Notch pathway was activated after the very first two cell divisions, when the embryo consists of only four cells. Genetic manipulations combined with drug treatments that changed the activity of the Notch pathway confirmed that Notch and Hippo acted independently at this stage. Further, larger-scale analysis of gene activity in these embryos also revealed that Notch signalling was working in a previously unknown way: it turned off the genes that maintain potency, pushing the cells to become more specialised. Ultimately, identifying this new mode of action for the Notch pathway in the early embryo may help to understand how the signalling cascade acts in other types of processes. This knowledge could be useful, for example, to push embryonic cells grown in the laboratory towards a desired fate.
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Affiliation(s)
- Sergio Menchero
- Centro Nacional de Investigaciones Cardiovasculares Carlos III (CNIC), Madrid, Spain
| | - Isabel Rollan
- Centro Nacional de Investigaciones Cardiovasculares Carlos III (CNIC), Madrid, Spain
| | | | - Maria Jose Andreu
- Centro Nacional de Investigaciones Cardiovasculares Carlos III (CNIC), Madrid, Spain
| | - Julio Sainz de Aja
- Centro Nacional de Investigaciones Cardiovasculares Carlos III (CNIC), Madrid, Spain
| | - Minjung Kang
- Developmental Biology Program, Sloan Kettering Institute, New York, United States
| | - Javier Adan
- Centro Nacional de Investigaciones Cardiovasculares Carlos III (CNIC), Madrid, Spain
| | - Rui Benedito
- Molecular Genetics of Angiogenesis Group, Centro Nacional de Investigaciones Cardiovasculares Carlos III (CNIC), Madrid, Spain
| | - Teresa Rayon
- Centro Nacional de Investigaciones Cardiovasculares Carlos III (CNIC), Madrid, Spain
| | | | - Miguel Manzanares
- Centro Nacional de Investigaciones Cardiovasculares Carlos III (CNIC), Madrid, Spain
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Singh H, Sreedharan S, Tiwari K, Green NH, Smythe C, Pramanik SK, Thomas JA, Das A. Two photon excitable graphene quantum dots for structured illumination microscopy and imaging applications: lysosome specificity and tissue-dependent imaging. Chem Commun (Camb) 2019; 55:521-524. [DOI: 10.1039/c8cc08610a] [Citation(s) in RCA: 54] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Two-photon active graphene quantum dots (GQDs) are obtained from extracts of the neem root.
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Affiliation(s)
- Harwinder Singh
- CSIR-Central Salt and Marine Chemicals Research Institute
- Bhavnagar
- India
- Academy of Scientific & Innovative Research
- CSIR-CSMCRI
| | | | - Karishma Tiwari
- CSIR-Central Salt and Marine Chemicals Research Institute
- Bhavnagar
- India
| | - Nicola H. Green
- Department of Materials Science and Engineering
- Kroto Research Institute
- North Campus
- Broad Lane
- University of Sheffield
| | - Carl Smythe
- Department of Biomedical Science
- University of Sheffield
- Sheffield
- UK
| | | | - Jim A. Thomas
- Department of Chemistry
- University of Sheffield
- Western Bank
- Sheffield
- UK
| | - Amitava Das
- CSIR-Central Salt and Marine Chemicals Research Institute
- Bhavnagar
- India
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34
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Imai H, Fujii W, Kusakabe KT, Kiso Y, Kano K. Aggregation recovers developmental plasticity in mouse polyploid embryos. Reprod Fertil Dev 2019; 31:404-411. [DOI: 10.1071/rd18093] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2018] [Accepted: 07/21/2018] [Indexed: 11/23/2022] Open
Abstract
Tetraploid embryos normally develop into blastocysts and embryonic stem cells can be established from tetraploid blastocysts in mice. Thus, polyploidisation does not seem to be so harmful during preimplantation development. However, the mechanisms by which early mammalian development accepts polyploidisation are poorly understood. In this study, we aimed to elucidate the effect of polyploidisation on early mammalian development and to further comprehend its tolerance using hyperpolyploid embryos produced by repetitive whole genome duplication. We successfully established several types of polyploid embryos (tetraploid, octaploid and hexadecaploid) and studied their developmental potential invitro. We demonstrated that all types of these polyploid embryos maintained the ability to develop to the blastocyst stage, which implies that mammalian cells might have basic cellular functions in implanted embryos, despite polyploidisation. However, the inner cell mass was absent in hexadecaploid blastocysts. To complement the total number of cells in blastocysts, a fused hexadecaploid embryo was produced by aggregating several hexadecaploid embryos. The results indicated that the fused hexadecaploid embryo finally recovered pluripotent cells in the blastocyst. Thus, our findings suggest that early mammalian embryos may have the tolerance and higher plasticity to adapt to hyperpolyploidisation for blastocyst formation, despite intense alteration of the genome volume.
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35
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Pennings S, Revuelta A, McLaughlin KA, Abd Hadi NA, Petchreing P, Ottaviano R, Meehan RR. Dynamics and Mechanisms of DNA Methylation Reprogramming. EPIGENETICS AND REGENERATION 2019:19-45. [DOI: 10.1016/b978-0-12-814879-2.00002-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/02/2023]
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36
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Asymmetric Expression of LincGET Biases Cell Fate in Two-Cell Mouse Embryos. Cell 2018; 175:1887-1901.e18. [DOI: 10.1016/j.cell.2018.11.039] [Citation(s) in RCA: 63] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2018] [Revised: 07/01/2018] [Accepted: 11/22/2018] [Indexed: 11/21/2022]
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37
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Xavier da Silveira Dos Santos A, Liberali P. From single cells to tissue self-organization. FEBS J 2018; 286:1495-1513. [PMID: 30390414 PMCID: PMC6519261 DOI: 10.1111/febs.14694] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2018] [Revised: 10/10/2018] [Accepted: 11/02/2018] [Indexed: 12/16/2022]
Abstract
Self-organization is a process by which interacting cells organize and arrange themselves in higher order structures and patterns. To achieve this, cells must have molecular mechanisms to sense their complex local environment and interpret it to respond accordingly. A combination of cell-intrinsic and cell-extrinsic cues are decoded by the single cells dictating their behaviour, their differentiation and symmetry-breaking potential driving development, tissue remodeling and regenerative processes. A unifying property of these self-organized pattern-forming systems is the importance of fluctuations, cell-to-cell variability, or noise. Cell-to-cell variability is an inherent and emergent property of populations of cells that maximize the population performance instead of the individual cell, providing tissues the flexibility to develop and maintain homeostasis in diverse environments. In this review, we will explore the role of self-organization and cell-to-cell variability as fundamental properties of multicellularity-and the requisite of single-cell resolution for its understanding. Moreover, we will analyze how single cells generate emergent multicellular dynamics observed at the tissue level 'travelling' across different scales: spatial, temporal and functional.
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Affiliation(s)
| | - Prisca Liberali
- Friedrich Miescher Institute for Biomedical Research (FMI), Basel, Switzerland.,University of Basel, Switzerland
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38
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Almonacid M, Terret ME, Verlhac MH. Control of nucleus positioning in mouse oocytes. Semin Cell Dev Biol 2018; 82:34-40. [DOI: 10.1016/j.semcdb.2017.08.010] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2017] [Accepted: 08/03/2017] [Indexed: 12/15/2022]
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39
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40
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Biase FH, Wu Q, Calandrelli R, Rivas-Astroza M, Zhou S, Chen Z, Zhong S. Rainbow-Seq: Combining Cell Lineage Tracing with Single-Cell RNA Sequencing in Preimplantation Embryos. iScience 2018; 7:16-29. [PMID: 30267678 PMCID: PMC6135740 DOI: 10.1016/j.isci.2018.08.009] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2018] [Revised: 08/01/2018] [Accepted: 08/10/2018] [Indexed: 02/06/2023] Open
Abstract
We developed the Rainbow-seq technology to trace cell division history and reveal single-cell transcriptomes. With distinct fluorescent protein genes as lineage markers, Rainbow-seq enables each single-cell RNA sequencing (RNA-seq) experiment to simultaneously decode the lineage marker genes and read single-cell transcriptomes. We triggered lineage tracking in each blastomere at the 2-cell stage, observed microscopically inequivalent contributions of the progeny to the two embryonic poles at the blastocyst stage, and analyzed every single cell at either 4- or 8-cell stage with deep paired-end sequencing of full-length transcripts. Although lineage difference was not marked unequivocally at a single-gene level, it became clear when the transcriptome was analyzed as a whole. Moreover, several groups of novel transcript isoforms with embedded repeat sequences exhibited lineage difference, suggesting a possible link between DNA demethylation and cell fate decision. Rainbow-seq bridged a critical gap between division history and single-cell RNA-seq assays.
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Affiliation(s)
- Fernando H Biase
- Department of Bioengineering, University of California San Diego, San Diego, CA 92130, USA
| | - Qiuyang Wu
- Department of Bioengineering, University of California San Diego, San Diego, CA 92130, USA; Department of Computer Science and Technology, Tongji University, Shanghai 201804, China
| | - Riccardo Calandrelli
- Department of Bioengineering, University of California San Diego, San Diego, CA 92130, USA
| | - Marcelo Rivas-Astroza
- Department of Bioengineering, University of California San Diego, San Diego, CA 92130, USA
| | - Shuigeng Zhou
- School of Computer Science, Fudan University, Shanghai 200433, China
| | - Zhen Chen
- Department of Diabetes Complications and Metabolism, City of Hope, Duarte, CA 91010, USA
| | - Sheng Zhong
- Department of Bioengineering, University of California San Diego, San Diego, CA 92130, USA.
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Abstract
We present an overview of symmetry breaking in early mammalian development as a continuous process from compaction to specification of the body axes. While earlier studies have focused on individual symmetry-breaking events, recent advances enable us to explore progressive symmetry breaking during early mammalian development. Although we primarily discuss embryonic development of the mouse, as it is the best-studied mammalian model system to date, we also highlight the shared and distinct aspects between different mammalian species. Finally, we discuss how insights gained from studying mammalian development can be generalized in light of self-organization principles. With this review, we hope to highlight new perspectives in studying symmetry breaking and self-organization in multicellular systems.
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Affiliation(s)
- Hui Ting Zhang
- European Molecular Biology Laboratory, 69117 Heidelberg, Germany;
| | - Takashi Hiiragi
- European Molecular Biology Laboratory, 69117 Heidelberg, Germany;
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42
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Yekani F, Azarnia M, Esfandiari F, Hassani SN, Baharvand H. Enhanced development of mouse single blastomeres into blastocysts via the simultaneous inhibition of TGF-β and ERK pathways in microdroplet culture. J Cell Biochem 2018; 119:7621-7630. [PMID: 29923640 DOI: 10.1002/jcb.27106] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2017] [Accepted: 04/07/2018] [Indexed: 11/12/2022]
Abstract
Optimization of an in vitro culture that supports blastocyst (BL) development from single blastomeres (SBs) is essential to generate additional embryos for farm animals and humans and unravel the mechanisms that underlie totipotency. In this study, we have examined BL development from SBs that were derived from 2-cell and 4-cell mouse embryos in different media. Moreover, BLs were assessed for inner cell mass (ICM) by staining with Oct4. We found that BL development was improved in a lower volume of medium (1 µL) compared with a higher volume (5 µL). Furthermore, the supplementation of medium with the inhibitors of ERK1/2 and TGFβ (R2i) signaling pathways in 1 µL droplets of T6 medium improved BL development. The co-culture of SBs with intact embryos in the presence of R2i showed more BL development and ICM to trophectoderm cell number ratio in comparison with SB culture and SB group culture. We also observed reduced total cell number, ICM, and trophectoderm cell numbers in all of the SB culture conditions versus intact embryo development. These findings might facilitate the successful generation of additional embryos for biomedical applications and elucidate the mechanisms that underlie totipotency.
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Affiliation(s)
- Farshid Yekani
- Department of Animal Biology, Faculty of Biological Sciences, Kharazmi University, Tehran, Iran.,Department of Stem Cells and Developmental Biology, Cell Science Research Center, Royan Institute for Stem Cell Biology and Technology, ACECR, Tehran, Iran
| | - Mahnaz Azarnia
- Department of Animal Biology, Faculty of Biological Sciences, Kharazmi University, Tehran, Iran
| | - Fereshteh Esfandiari
- Department of Stem Cells and Developmental Biology, Cell Science Research Center, Royan Institute for Stem Cell Biology and Technology, ACECR, Tehran, Iran
| | - Seyedeh-Nafiseh Hassani
- Department of Stem Cells and Developmental Biology, Cell Science Research Center, Royan Institute for Stem Cell Biology and Technology, ACECR, Tehran, Iran
| | - Hossein Baharvand
- Department of Stem Cells and Developmental Biology, Cell Science Research Center, Royan Institute for Stem Cell Biology and Technology, ACECR, Tehran, Iran.,Department of Developmental Biology, University of Science and Culture, Tehran, Iran
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White MD, Zenker J, Bissiere S, Plachta N. Instructions for Assembling the Early Mammalian Embryo. Dev Cell 2018; 45:667-679. [DOI: 10.1016/j.devcel.2018.05.013] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2017] [Revised: 01/23/2018] [Accepted: 05/10/2018] [Indexed: 12/15/2022]
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44
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Toda S, Blauch LR, Tang SKY, Morsut L, Lim WA. Programming self-organizing multicellular structures with synthetic cell-cell signaling. Science 2018; 361:156-162. [PMID: 29853554 DOI: 10.1126/science.aat0271] [Citation(s) in RCA: 239] [Impact Index Per Article: 39.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2018] [Accepted: 05/22/2018] [Indexed: 12/13/2022]
Abstract
A common theme in the self-organization of multicellular tissues is the use of cell-cell signaling networks to induce morphological changes. We used the modular synNotch juxtacrine signaling platform to engineer artificial genetic programs in which specific cell-cell contacts induced changes in cadherin cell adhesion. Despite their simplicity, these minimal intercellular programs were sufficient to yield assemblies with hallmarks of natural developmental systems: robust self-organization into multidomain structures, well-choreographed sequential assembly, cell type divergence, symmetry breaking, and the capacity for regeneration upon injury. The ability of these networks to drive complex structure formation illustrates the power of interlinking cell signaling with cell sorting: Signal-induced spatial reorganization alters the local signals received by each cell, resulting in iterative cycles of cell fate branching. These results provide insights into the evolution of multicellularity and demonstrate the potential to engineer customized self-organizing tissues or materials.
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Affiliation(s)
- Satoshi Toda
- Department of Cellular and Molecular Pharmacology, Howard Hughes Medical Institute, and Center for Systems and Synthetic Biology, University of California, San Francisco, CA 94158, USA
| | - Lucas R Blauch
- Department of Mechanical Engineering, Stanford University, Stanford, CA 94305, USA
| | - Sindy K Y Tang
- Department of Mechanical Engineering, Stanford University, Stanford, CA 94305, USA
| | - Leonardo Morsut
- Department of Cellular and Molecular Pharmacology, Howard Hughes Medical Institute, and Center for Systems and Synthetic Biology, University of California, San Francisco, CA 94158, USA. .,Present address: Eli and Edythe Broad CIRM Center for Regenerative Medicine and Stem Cell Research, University of Southern California, Los Angeles, CA 90033, USA
| | - Wendell A Lim
- Department of Cellular and Molecular Pharmacology, Howard Hughes Medical Institute, and Center for Systems and Synthetic Biology, University of California, San Francisco, CA 94158, USA.
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45
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Blastocyst-like structures generated solely from stem cells. Nature 2018; 557:106-111. [PMID: 29720634 DOI: 10.1038/s41586-018-0051-0] [Citation(s) in RCA: 310] [Impact Index Per Article: 51.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2015] [Accepted: 02/28/2018] [Indexed: 02/07/2023]
Abstract
The blastocyst (the early mammalian embryo) forms all embryonic and extra-embryonic tissues, including the placenta. It consists of a spherical thin-walled layer, known as the trophectoderm, that surrounds a fluid-filled cavity sheltering the embryonic cells 1 . From mouse blastocysts, it is possible to derive both trophoblast 2 and embryonic stem-cell lines 3 , which are in vitro analogues of the trophectoderm and embryonic compartments, respectively. Here we report that trophoblast and embryonic stem cells cooperate in vitro to form structures that morphologically and transcriptionally resemble embryonic day 3.5 blastocysts, termed blastoids. Like blastocysts, blastoids form from inductive signals that originate from the inner embryonic cells and drive the development of the outer trophectoderm. The nature and function of these signals have been largely unexplored. Genetically and physically uncoupling the embryonic and trophectoderm compartments, along with single-cell transcriptomics, reveals the extensive inventory of embryonic inductions. We specifically show that the embryonic cells maintain trophoblast proliferation and self-renewal, while fine-tuning trophoblast epithelial morphogenesis in part via a BMP4/Nodal-KLF6 axis. Although blastoids do not support the development of bona fide embryos, we demonstrate that embryonic inductions are crucial to form a trophectoderm state that robustly implants and triggers decidualization in utero. Thus, at this stage, the nascent embryo fuels trophectoderm development and implantation.
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Eckersley-Maslin MA, Alda-Catalinas C, Reik W. Dynamics of the epigenetic landscape during the maternal-to-zygotic transition. Nat Rev Mol Cell Biol 2018; 19:436-450. [DOI: 10.1038/s41580-018-0008-z] [Citation(s) in RCA: 198] [Impact Index Per Article: 33.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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Psychiatry in a Dish: Stem Cells and Brain Organoids Modeling Autism Spectrum Disorders. Biol Psychiatry 2018; 83:558-568. [PMID: 29295738 DOI: 10.1016/j.biopsych.2017.11.011] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/05/2017] [Revised: 11/03/2017] [Accepted: 11/03/2017] [Indexed: 12/23/2022]
Abstract
Autism spectrum disorders are a group of pervasive neurodevelopmental conditions with heterogeneous etiology, characterized by deficits in social cognition, communication, and behavioral flexibility. Despite an increasing scientific effort to find the pathophysiological explanations for the disease, the neurobiological links remain unclear. A large amount of evidence suggests that pathological processes taking place in early embryonic neurodevelopment might be responsible for later manifestation of autistic symptoms. This dysfunctional development includes altered maturation/differentiation processes, disturbances in cell-cell communication, and an unbalanced ratio between certain neuronal populations. All those processes are highly dependent on the interconnectivity and three-dimensional organizations of the brain. Moreover, in order to gain a deeper understanding of the complex neurobiology of autism spectrum disorders, valid disease models are pivotal. Induced pluripotent stem cells could potentially help to elucidate the complex mechanisms of the disease and lead to the development of more effective individualized treatment. The induced pluripotent stem cells approach allows comparison between the development of various cellular phenotypes generated from cell lines of patients and healthy individuals. A newly advanced organoid technology makes it possible to create three-dimensional in vitro models of brain development and structural interconnectivity, based on induced pluripotent stem cells derived from the respective individuals. The biggest challenge for modeling psychiatric diseases in vitro is finding and establishing the link between cellular and molecular findings with the clinical symptoms, and this review aims to give an overview over the feasibility and applicability of this new tissue engineering tool in psychiatry.
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Wang X, Luo M, Wu H, Zhang Z, Liu J, Xu Z, Johnson W, Sun Y. A Three-Dimensional Magnetic Tweezer System for Intraembryonic Navigation and Measurement. IEEE T ROBOT 2018. [DOI: 10.1109/tro.2017.2765673] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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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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van Haastert PJM, Keizer-Gunnink I, Kortholt A. The cytoskeleton regulates symmetry transitions in moving amoeboid cells. J Cell Sci 2018; 131:jcs.208892. [DOI: 10.1242/jcs.208892] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2017] [Accepted: 02/19/2018] [Indexed: 01/24/2023] Open
Abstract
Symmetry and symmetry breaking are essential in biology. Symmetry comes in different forms: rotational symmetry, mirror symmetry and alternating right/left symmetry. Especially the transitions between the different symmetry forms specify crucial points in cell biology, including gastrulation in development, formation of the cleavage furrow in cell division, or the front in cell polarity. However, the mechanisms of these symmetry transitions are not well understood. Here we have investigated the fundaments of symmetry and symmetry transitions of the cytoskeleton during cell movement. Our data show that the dynamic shape changes of amoeboid cells are far from random, but are the consequence of refined symmetries and symmetry changes that are orchestrated by small G-proteins and the cytoskeleton, with local stimulation by F-actin and Scar , and local inhibition by IQGAP2 and myosin.
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Affiliation(s)
- Peter J. M. van Haastert
- Department of Cell Biochemistry, University of Groningen, Nijenborgh 7, 9747 AG Groningen, The Netherlands
| | - Ineke Keizer-Gunnink
- Department of Cell Biochemistry, University of Groningen, Nijenborgh 7, 9747 AG Groningen, The Netherlands
| | - Arjan Kortholt
- Department of Cell Biochemistry, University of Groningen, Nijenborgh 7, 9747 AG Groningen, The Netherlands
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