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Merle M, Friedman L, Chureau C, Shoushtarizadeh A, Gregor T. Precise and scalable self-organization in mammalian pseudo-embryos. Nat Struct Mol Biol 2024; 31:896-902. [PMID: 38491138 DOI: 10.1038/s41594-024-01251-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2023] [Accepted: 02/08/2024] [Indexed: 03/18/2024]
Abstract
Gene expression is inherently noisy, posing a challenge to understanding how precise and reproducible patterns of gene expression emerge in mammals. Here we investigate this phenomenon using gastruloids, a three-dimensional in vitro model for early mammalian development. Our study reveals intrinsic reproducibility in the self-organization of gastruloids, encompassing growth dynamics and gene expression patterns. We observe a remarkable degree of control over gene expression along the main body axis, with pattern boundaries positioned with single-cell precision. Furthermore, as gastruloids grow, both their physical proportions and gene expression patterns scale proportionally with system size. Notably, these properties emerge spontaneously in self-organizing cell aggregates, distinct from many in vivo systems constrained by fixed boundary conditions. Our findings shed light on the intricacies of developmental precision, reproducibility and size scaling within a mammalian system, suggesting that these phenomena might constitute fundamental features of multicellularity.
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Affiliation(s)
- Mélody Merle
- Department of Developmental and Stem Cell Biology, CNRS UMR3738 Paris Cité, Institut Pasteur, Paris, France
| | - Leah Friedman
- Department of Developmental and Stem Cell Biology, CNRS UMR3738 Paris Cité, Institut Pasteur, Paris, France
| | - Corinne Chureau
- Department of Developmental and Stem Cell Biology, CNRS UMR3738 Paris Cité, Institut Pasteur, Paris, France
| | - Armin Shoushtarizadeh
- Department of Developmental and Stem Cell Biology, CNRS UMR3738 Paris Cité, Institut Pasteur, Paris, France
| | - Thomas Gregor
- Department of Developmental and Stem Cell Biology, CNRS UMR3738 Paris Cité, Institut Pasteur, Paris, France.
- Joseph Henry Laboratories of Physics & Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ, USA.
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2
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Li JH, Trivedi V, Diz-Muñoz A. Understanding the interplay of membrane trafficking, cell surface mechanics, and stem cell differentiation. Semin Cell Dev Biol 2023; 133:123-134. [PMID: 35641408 PMCID: PMC9703995 DOI: 10.1016/j.semcdb.2022.05.010] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Revised: 04/08/2022] [Accepted: 05/14/2022] [Indexed: 01/17/2023]
Abstract
Stem cells can generate a diversity of cell types during development, regeneration and adult tissue homeostasis. Differentiation changes not only the cell fate in terms of gene expression but also the physical properties and functions of cells, e.g. the secretory activity, cell shape, or mechanics. Conversely, these activities and properties can also regulate differentiation itself. Membrane trafficking is known to modulate signal transduction and thus has the potential to control stem cell differentiation. On the other hand, membrane trafficking, particularly from and to the plasma membrane, depends on the mechanical properties of the cell surface such as tension within the plasma membrane or the cortex. Indeed, recent findings demonstrate that cell surface mechanics can also control cell fate. Here, we review the bidirectional relationships between these three fundamental cellular functions, i.e. membrane trafficking, cell surface mechanics, and stem cell differentiation. Furthermore, we discuss commonly used methods in each field and how combining them with new tools will enhance our understanding of their interplay. Understanding how membrane trafficking and cell surface mechanics can guide stem cell fate holds great potential as these concepts could be exploited for directed differentiation of stem cells for the fields of tissue engineering and regenerative medicine.
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Affiliation(s)
- Jia Hui Li
- Cell Biology and Biophysics Unit, European Molecular Biology Laboratory (EMBL), Meyerhofstraße 1, Heidelberg 69117, Germany
| | - Vikas Trivedi
- EMBL, PRBB, Dr. Aiguader, 88, Barcelona 08003, Spain,Developmental Biology Unit, EMBL, Meyerhofstraße 1, Heidelberg 69117, Germany
| | - Alba Diz-Muñoz
- Cell Biology and Biophysics Unit, European Molecular Biology Laboratory (EMBL), Meyerhofstraße 1, Heidelberg 69117, Germany.
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3
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Ahmadi A, Mazloomnejad R, Kasravi M, Gholamine B, Bahrami S, Sarzaeem MM, Niknejad H. Recent advances on small molecules in osteogenic differentiation of stem cells and the underlying signaling pathways. Stem Cell Res Ther 2022; 13:518. [PMID: 36371202 PMCID: PMC9652959 DOI: 10.1186/s13287-022-03204-4] [Citation(s) in RCA: 23] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2022] [Accepted: 10/09/2022] [Indexed: 11/15/2022] Open
Abstract
Bone-related diseases are major contributors to morbidity and mortality in elderly people and the current treatments result in insufficient healing and several complications. One of the promising areas of research for healing bone fractures and skeletal defects is regenerative medicine using stem cells. Differentiating stem cells using agents that shift cell development towards the preferred lineage requires activation of certain intracellular signaling pathways, many of which are known to induce osteogenesis during embryological stages. Imitating embryological bone formation through activation of these signaling pathways has been the focus of many osteogenic studies. Activation of osteogenic signaling can be done by using small molecules. Several of these agents, e.g., statins, metformin, adenosine, and dexamethasone have other clinical uses but have also shown osteogenic capacities. On the other hand, some other molecules such as T63 and tetrahydroquinolines are not as well recognized in the clinic. Osteogenic small molecules exert their effects through the activation of signaling pathways known to be related to osteogenesis. These pathways include more well-known pathways including BMP/Smad, Wnt, and Hedgehog as well as ancillary pathways including estrogen signaling and neuropeptide signaling. In this paper, we review the recent data on small molecule-mediated osteogenic differentiation, possible adjunctive agents with these molecules, and the signaling pathways through which each small molecule exerts its effects.
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Affiliation(s)
- Armin Ahmadi
- Department of Pharmacology, School of Medicine, Shahid Beheshti University of Medical Sciences, P.O. Box: 1985711151, Tehran, Iran
| | - Radman Mazloomnejad
- Department of Pharmacology, School of Medicine, Shahid Beheshti University of Medical Sciences, P.O. Box: 1985711151, Tehran, Iran
| | - Mohammadreza Kasravi
- Department of Pharmacology, School of Medicine, Shahid Beheshti University of Medical Sciences, P.O. Box: 1985711151, Tehran, Iran
| | - Babak Gholamine
- Department of Pharmacology, School of Medicine, Shahid Beheshti University of Medical Sciences, P.O. Box: 1985711151, Tehran, Iran
| | - Soheyl Bahrami
- Ludwig Boltzmann Institute for Experimental and Clinical Traumatology in AUVA Research Center, Vienna, Austria
| | - Mohammad Mahdi Sarzaeem
- Department of Orthopedic Surgery, Imam Hossein Medical Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Hassan Niknejad
- Department of Pharmacology, School of Medicine, Shahid Beheshti University of Medical Sciences, P.O. Box: 1985711151, Tehran, Iran.
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4
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Diacou R, Nandigrami P, Fiser A, Liu W, Ashery-Padan R, Cvekl A. Cell fate decisions, transcription factors and signaling during early retinal development. Prog Retin Eye Res 2022; 91:101093. [PMID: 35817658 PMCID: PMC9669153 DOI: 10.1016/j.preteyeres.2022.101093] [Citation(s) in RCA: 28] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2022] [Revised: 06/02/2022] [Accepted: 06/03/2022] [Indexed: 12/30/2022]
Abstract
The development of the vertebrate eyes is a complex process starting from anterior-posterior and dorso-ventral patterning of the anterior neural tube, resulting in the formation of the eye field. Symmetrical separation of the eye field at the anterior neural plate is followed by two symmetrical evaginations to generate a pair of optic vesicles. Next, reciprocal invagination of the optic vesicles with surface ectoderm-derived lens placodes generates double-layered optic cups. The inner and outer layers of the optic cups develop into the neural retina and retinal pigment epithelium (RPE), respectively. In vitro produced retinal tissues, called retinal organoids, are formed from human pluripotent stem cells, mimicking major steps of retinal differentiation in vivo. This review article summarizes recent progress in our understanding of early eye development, focusing on the formation the eye field, optic vesicles, and early optic cups. Recent single-cell transcriptomic studies are integrated with classical in vivo genetic and functional studies to uncover a range of cellular mechanisms underlying early eye development. The functions of signal transduction pathways and lineage-specific DNA-binding transcription factors are dissected to explain cell-specific regulatory mechanisms underlying cell fate determination during early eye development. The functions of homeodomain (HD) transcription factors Otx2, Pax6, Lhx2, Six3 and Six6, which are required for early eye development, are discussed in detail. Comprehensive understanding of the mechanisms of early eye development provides insight into the molecular and cellular basis of developmental ocular anomalies, such as optic cup coloboma. Lastly, modeling human development and inherited retinal diseases using stem cell-derived retinal organoids generates opportunities to discover novel therapies for retinal diseases.
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Affiliation(s)
- Raven Diacou
- Department of Genetics, Albert Einstein College of Medicine, Bronx, NY, 10461, USA; Department of Ophthalmology and Visual Sciences, Albert Einstein College of Medicine, Bronx, NY, 10461, USA
| | - Prithviraj Nandigrami
- Department of Systems and Computational Biology, Albert Einstein College of Medicine, Bronx, NY, 10461, USA; Department of Biochemistry, Albert Einstein College of Medicine, Bronx, NY, 10461, USA
| | - Andras Fiser
- Department of Systems and Computational Biology, Albert Einstein College of Medicine, Bronx, NY, 10461, USA; Department of Biochemistry, Albert Einstein College of Medicine, Bronx, NY, 10461, USA
| | - Wei Liu
- Department of Genetics, Albert Einstein College of Medicine, Bronx, NY, 10461, USA; Department of Ophthalmology and Visual Sciences, Albert Einstein College of Medicine, Bronx, NY, 10461, USA
| | - Ruth Ashery-Padan
- Sackler School of Medicine, Tel Aviv University, Tel Aviv, 69978, Israel
| | - Ales Cvekl
- Department of Genetics, Albert Einstein College of Medicine, Bronx, NY, 10461, USA; Department of Ophthalmology and Visual Sciences, Albert Einstein College of Medicine, Bronx, NY, 10461, USA.
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5
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Oriola D, Marin-Riera M, Anlaş K, Gritti N, Sanaki-Matsumiya M, Aalderink G, Ebisuya M, Sharpe J, Trivedi V. Arrested coalescence of multicellular aggregates. SOFT MATTER 2022; 18:3771-3780. [PMID: 35511111 DOI: 10.1039/d2sm00063f] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Multicellular aggregates are known to exhibit liquid-like properties. The fusion process of two cell aggregates is commonly studied as the coalescence of two viscous drops. However, tissues are complex materials and can exhibit viscoelastic behaviour. It is known that elastic effects can prevent the complete fusion of two drops, a phenomenon known as arrested coalescence. Here we study this phenomenon in stem cell aggregates and provide a theoretical framework which agrees with the experiments. In addition, agent-based simulations show that active cell fluctuations can control a solid-to-fluid phase transition, revealing that arrested coalescence can be found in the vicinity of an unjamming transition. By analysing the dynamics of the fusion process and combining it with nanoindentation measurements, we obtain the effective viscosity, shear modulus and surface tension of the aggregates. More generally, our work provides a simple, fast and inexpensive method to characterize the mechanical properties of viscoelastic materials.
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Affiliation(s)
- David Oriola
- European Molecular Biology Laboratory, EMBL Barcelona, Dr. Aiguader 88, PRBB Building, 08003, Barcelona, Spain.
| | - Miquel Marin-Riera
- European Molecular Biology Laboratory, EMBL Barcelona, Dr. Aiguader 88, PRBB Building, 08003, Barcelona, Spain.
| | - Kerim Anlaş
- European Molecular Biology Laboratory, EMBL Barcelona, Dr. Aiguader 88, PRBB Building, 08003, Barcelona, Spain.
| | - Nicola Gritti
- European Molecular Biology Laboratory, EMBL Barcelona, Dr. Aiguader 88, PRBB Building, 08003, Barcelona, Spain.
| | - Marina Sanaki-Matsumiya
- European Molecular Biology Laboratory, EMBL Barcelona, Dr. Aiguader 88, PRBB Building, 08003, Barcelona, Spain.
| | - Germaine Aalderink
- European Molecular Biology Laboratory, EMBL Barcelona, Dr. Aiguader 88, PRBB Building, 08003, Barcelona, Spain.
| | - Miki Ebisuya
- European Molecular Biology Laboratory, EMBL Barcelona, Dr. Aiguader 88, PRBB Building, 08003, Barcelona, Spain.
| | - James Sharpe
- European Molecular Biology Laboratory, EMBL Barcelona, Dr. Aiguader 88, PRBB Building, 08003, Barcelona, Spain.
- Institució Catalana de Recerca i Estudis Avançats, 08010, Barcelona, Spain
| | - Vikas Trivedi
- European Molecular Biology Laboratory, EMBL Barcelona, Dr. Aiguader 88, PRBB Building, 08003, Barcelona, Spain.
- European Molecular Biology Laboratory, Developmental Biology Unit, Meyerhofstraße 1, 69117 Heidelberg, Germany
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6
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Veenvliet JV, Lenne PF, Turner DA, Nachman I, Trivedi V. Sculpting with stem cells: how models of embryo development take shape. Development 2021; 148:dev192914. [PMID: 34908102 PMCID: PMC8722391 DOI: 10.1242/dev.192914] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
During embryogenesis, organisms acquire their shape given boundary conditions that impose geometrical, mechanical and biochemical constraints. A detailed integrative understanding how these morphogenetic information modules pattern and shape the mammalian embryo is still lacking, mostly owing to the inaccessibility of the embryo in vivo for direct observation and manipulation. These impediments are circumvented by the developmental engineering of embryo-like structures (stembryos) from pluripotent stem cells that are easy to access, track, manipulate and scale. Here, we explain how unlocking distinct levels of embryo-like architecture through controlled modulations of the cellular environment enables the identification of minimal sets of mechanical and biochemical inputs necessary to pattern and shape the mammalian embryo. We detail how this can be complemented with precise measurements and manipulations of tissue biochemistry, mechanics and geometry across spatial and temporal scales to provide insights into the mechanochemical feedback loops governing embryo morphogenesis. Finally, we discuss how, even in the absence of active manipulations, stembryos display intrinsic phenotypic variability that can be leveraged to define the constraints that ensure reproducible morphogenesis in vivo.
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Affiliation(s)
- Jesse V. Veenvliet
- Stembryogenesis Lab, Max Planck Institute of Molecular Cell Biology and Genetics, Pfotenhauerstrasse 108, 01307 Dresden, Germany
- Department of Developmental Genetics, Max Planck Institute for Molecular Genetics, Ihnestrasse 63-73, 14195 Berlin, Germany
- Cluster of Excellence Physics of Life, Technische Universität Dresden, 01307 Dresden, Germany
| | - Pierre-François Lenne
- Aix Marseille University, CNRS, IBDM, Turing Center for Living Systems, 13288, Marseille, France
| | - David A. Turner
- Institute of Life Course and Medical Sciences, William Henry Duncan Building, University of Liverpool, Liverpool, L7 8TX, UK
| | - Iftach Nachman
- School of Neurobiology, Biochemistry and Biophysics, Tel Aviv University, 6997801, Tel Aviv, Israel
| | - Vikas Trivedi
- European Molecular Biology Laboratories (EMBL), Barcelona, 08003, Spain
- EMBL Heidelberg, Developmental Biology Unit, 69117, Heidelberg, Germany
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7
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Gritti N, Lim JL, Anlaş K, Pandya M, Aalderink G, Martínez-Ara G, Trivedi V. MOrgAna: accessible quantitative analysis of organoids with machine learning. Development 2021; 148:dev199611. [PMID: 34494114 PMCID: PMC8451065 DOI: 10.1242/dev.199611] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Accepted: 07/12/2021] [Indexed: 12/20/2022]
Abstract
Recent years have seen a dramatic increase in the application of organoids to developmental biology, biomedical and translational studies. Organoids are large structures with high phenotypic complexity and are imaged on a wide range of platforms, from simple benchtop stereoscopes to high-content confocal-based imaging systems. The large volumes of images, resulting from hundreds of organoids cultured at once, are becoming increasingly difficult to inspect and interpret. Hence, there is a pressing demand for a coding-free, intuitive and scalable solution that analyses such image data in an automated yet rapid manner. Here, we present MOrgAna, a Python-based software that implements machine learning to segment images, quantify and visualize morphological and fluorescence information of organoids across hundreds of images, each with one object, within minutes. Although the MOrgAna interface is developed for users with little to no programming experience, its modular structure makes it a customizable package for advanced users. We showcase the versatility of MOrgAna on several in vitro systems, each imaged with a different microscope, thus demonstrating the wide applicability of the software to diverse organoid types and biomedical studies.
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Affiliation(s)
- Nicola Gritti
- European Molecular Biology Laboratory (EMBL), Barcelona 08003, Spain
| | - Jia Le Lim
- European Molecular Biology Laboratory (EMBL), Barcelona 08003, Spain
| | - Kerim Anlaş
- European Molecular Biology Laboratory (EMBL), Barcelona 08003, Spain
| | - Mallica Pandya
- European Molecular Biology Laboratory (EMBL), Barcelona 08003, Spain
| | | | | | - Vikas Trivedi
- European Molecular Biology Laboratory (EMBL), Barcelona 08003, Spain
- EMBL Heidelberg, Developmental Biology Unit, 69117 Heidelberg, Germany
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8
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Anlas K, Trivedi V. Studying evolution of the primary body axis in vivo and in vitro. eLife 2021; 10:e69066. [PMID: 34463611 PMCID: PMC8456739 DOI: 10.7554/elife.69066] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2021] [Accepted: 07/27/2021] [Indexed: 02/06/2023] Open
Abstract
The metazoan body plan is established during early embryogenesis via collective cell rearrangements and evolutionarily conserved gene networks, as part of a process commonly referred to as gastrulation. While substantial progress has been achieved in terms of characterizing the embryonic development of several model organisms, underlying principles of many early patterning processes nevertheless remain enigmatic. Despite the diversity of (pre-)gastrulating embryo and adult body shapes across the animal kingdom, the body axes, which are arguably the most fundamental features, generally remain identical between phyla. Recently there has been a renewed appreciation of ex vivo and in vitro embryo-like systems to model early embryonic patterning events. Here, we briefly review key examples and propose that similarities in morphogenesis and associated gene expression dynamics may reveal an evolutionarily conserved developmental mode as well as provide further insights into the role of external or extraembryonic cues in shaping the early embryo. In summary, we argue that embryo-like systems can be employed to inform previously uncharted aspects of animal body plan evolution as well as associated patterning rules.
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Affiliation(s)
| | - Vikas Trivedi
- EMBL BarcelonaBarcelonaSpain
- EMBL Heidelberg, Developmental BiologyHeidelbergGermany
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9
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van den Brink SC, van Oudenaarden A. 3D gastruloids: a novel frontier in stem cell-based in vitro modeling of mammalian gastrulation. Trends Cell Biol 2021; 31:747-759. [PMID: 34304959 DOI: 10.1016/j.tcb.2021.06.007] [Citation(s) in RCA: 52] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Revised: 06/16/2021] [Accepted: 06/18/2021] [Indexed: 12/24/2022]
Abstract
3D gastruloids, aggregates of embryonic stem cells that recapitulate key aspects of gastrula-stage embryos, have emerged as a powerful tool to study the early stages of mammalian post-implantation development in vitro. Owing to their tractable nature and the relative ease by which they can be generated in large numbers, 3D gastruloids provide an unparalleled opportunity to study normal and pathological embryogenesis from a bottom-up perspective and in a high-throughput manner. Here, we review how gastruloid models can be exploited to deepen our understanding of mammalian development. In addition, we discuss current limitations, potential clinical applications, and ethical implications of this emerging model system.
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Affiliation(s)
- Susanne C van den Brink
- Oncode Institute, Hubrecht Institute-KNAW (Royal Netherlands Academy of Arts and Sciences) and University Medical Center Utrecht, Utrecht, The Netherlands.
| | - Alexander van Oudenaarden
- Oncode Institute, Hubrecht Institute-KNAW (Royal Netherlands Academy of Arts and Sciences) and University Medical Center Utrecht, Utrecht, The Netherlands
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10
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Oriola D, Spagnoli FM. Engineering life in synthetic systems. Development 2021; 148:270849. [PMID: 34251450 DOI: 10.1242/dev.199497] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2021] [Accepted: 06/01/2021] [Indexed: 11/20/2022]
Abstract
The second EMBO-EMBL Symposium 'Synthetic Morphogenesis: From Gene Circuits to Tissue Architecture' was held virtually in March 2021, with participants from all over the world joining from the comfort of their sofas to discuss synthetic morphogenesis at large. Leading scientists from a range of disciplines, including developmental biology, physics, chemistry and computer science, covered a gamut of topics from the principles of cell and tissue organization, patterning and gene regulatory networks, to synthetic approaches for exploring evolutionary and developmental biology principles. Here, we describe some of the high points.
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Affiliation(s)
- David Oriola
- EMBL Barcelona, Dr Aiguader 88, 08003 Barcelona, Spain
| | - Francesca M Spagnoli
- Centre for Stem Cells and Regenerative Medicine, King's College London, Guy's Hospital, Floor 28, Tower Wing, Great Maze Pond, London SE1 9RT, UK
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11
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Affiliation(s)
- Jake Cornwall-Scoones
- California Institute of Technology, Division of Biology and Biological Engineering, 1200 E. California Boulevard, Pasadena, CA, 91125, USA
| | - Magdalena Zernicka-Goetz
- California Institute of Technology, Division of Biology and Biological Engineering, 1200 E. California Boulevard, Pasadena, CA, 91125, USA; Mammalian Embryo and Stem Cell Group, University of Cambridge, Department of Physiology, Development and Neuroscience, Cambridge, CB2 3EG, UK.
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