1
|
Abstract
WNT/CTNNB1 signaling plays a critical role in the development of all multicellular animals. Here, we include both the embryonic stages, during which tissue morphogenesis takes place, and the postnatal stages of development, during which tissue homeostasis occurs. Thus, embryonic development concerns lineage development and cell fate specification, while postnatal development involves tissue maintenance and regeneration. Multiple tools are available to researchers who want to investigate, and ideally visualize, the dynamic and pleiotropic involvement of WNT/CTNNB1 signaling in these processes. Here, we discuss and evaluate the decisions that researchers need to make in identifying the experimental system and appropriate tools for the specific question they want to address, covering different types of WNT/CTNNB1 reporters in cells and mice. At a molecular level, advanced quantitative imaging techniques can provide spatio-temporal information that cannot be provided by traditional biochemical assays. We therefore also highlight some recent studies to show their potential in deciphering the complex and dynamic mechanisms that drive WNT/CTNNB1 signaling.
Collapse
|
2
|
Pour M, Kumar AS, Farag N, Bolondi A, Kretzmer H, Walther M, Wittler L, Meissner A, Nachman I. Emergence and patterning dynamics of mouse-definitive endoderm. iScience 2022; 25:103556. [PMID: 34988400 PMCID: PMC8693470 DOI: 10.1016/j.isci.2021.103556] [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] [Received: 05/11/2021] [Revised: 10/21/2021] [Accepted: 12/01/2021] [Indexed: 11/30/2022] Open
Abstract
The segregation of definitive endoderm (DE) from bipotent mesendoderm progenitors leads to the formation of two distinct germ layers. Dissecting DE commitment and onset has been challenging as it occurs within a narrow spatiotemporal window in the embryo. Here, we employ a dual Bra/Sox17 reporter cell line to study DE onset dynamics. We find Sox17 expression initiates in vivo in isolated cells within a temporally restricted window. In 2D and 3D in vitro models, DE cells emerge from mesendoderm progenitors at a temporally regular, but spatially stochastic pattern, which is subsequently arranged by self-sorting of Sox17 + cells. A subpopulation of Bra-high cells commits to a Sox17+ fate independent of external Wnt signal. Self-sorting coincides with upregulation of E-cadherin but is not necessary for DE differentiation or proliferation. Our in vivo and in vitro results highlight basic rules governing DE onset and patterning through the commonalities and differences between these systems. Sox17 onsets in a few isolated cells within Bra-expressing population Sox17 onset followed by expansion and self-sorting Final number of Sox17+ cells does not depend on self-sorting or cell movement The DE segregation pattern is similar in in vivo and in 2D, 3D in vitro systems
Collapse
Affiliation(s)
- Maayan Pour
- School of Neurobiology, Biochemistry and Biophysics, Department of Biochemistry and Molecular Biology, Tel Aviv University, Tel Aviv 6997801, Israel
| | - Abhishek Sampath Kumar
- Department of Genome Regulation, Max Planck Institute for Molecular Genetics, 14195 Berlin, Germany
| | - Naama Farag
- School of Neurobiology, Biochemistry and Biophysics, Department of Biochemistry and Molecular Biology, Tel Aviv University, Tel Aviv 6997801, Israel
| | - Adriano Bolondi
- Department of Genome Regulation, Max Planck Institute for Molecular Genetics, 14195 Berlin, Germany
| | - Helene Kretzmer
- Department of Genome Regulation, Max Planck Institute for Molecular Genetics, 14195 Berlin, Germany
| | - Maria Walther
- Department of Genome Regulation, Max Planck Institute for Molecular Genetics, 14195 Berlin, Germany
| | - Lars Wittler
- Department of Developmental Genetics, Max Planck Institute for Molecular Genetics, 14195 Berlin, Germany
| | - Alexander Meissner
- Department of Genome Regulation, Max Planck Institute for Molecular Genetics, 14195 Berlin, Germany.,Department of Stem Cell and Regenerative Biology, Harvard University, Cambridge, MA 02138, USA.,Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Iftach Nachman
- School of Neurobiology, Biochemistry and Biophysics, Department of Biochemistry and Molecular Biology, Tel Aviv University, Tel Aviv 6997801, Israel
| |
Collapse
|
3
|
Srivastava P, Kilian KA. Micro-Engineered Models of Development Using Induced Pluripotent Stem Cells. Front Bioeng Biotechnol 2019; 7:357. [PMID: 31850326 PMCID: PMC6895561 DOI: 10.3389/fbioe.2019.00357] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Accepted: 11/08/2019] [Indexed: 12/31/2022] Open
Abstract
During fetal development, embryonic cells are coaxed through a series of lineage choices which lead to the formation of the three germ layers and subsequently to all the cell types that are required to form an adult human body. Landmark cell fate decisions leading to symmetry breaking, establishment of the primitive streak and first tri-lineage differentiation happen after implantation, and therefore have been attributed to be a function of the embryo's spatiotemporal 3D environment. These mechanical and geometric cues induce a cascade of signaling pathways leading to cell differentiation and orientation. Due to the physiological, ethical, and legal limitations of accessing an intact human embryo for functional studies, multiple in-vitro models have been developed to try and recapitulate the key milestones of mammalian embryogenesis using mouse embryos, or mouse and human embryonic stem cells. More recently, the development of induced pluripotent stem cells represents a cell source which is being explored to prepare a developmental model, owing to their genetic and functional similarities to embryonic stem cells. Here we review the use of micro-engineered cell culture materials as platforms to define the physical and geometric contributions during the cell fate defining process and to study the underlying pathways. This information has applications in various biomedical contexts including tissue engineering, stem cell therapy, and organoid cultures for disease modeling.
Collapse
Affiliation(s)
- Pallavi Srivastava
- School of Medical Sciences, University of New South Wales, Sydney, NSW, Australia
- Australian Centre for Nanomedicine, School of Chemistry, School of Materials Science and Engineering, University of New South Wales, Sydney, NSW, Australia
| | - Kristopher A. Kilian
- Australian Centre for Nanomedicine, School of Chemistry, School of Materials Science and Engineering, University of New South Wales, Sydney, NSW, Australia
| |
Collapse
|
4
|
Vianello S, Lutolf MP. Understanding the Mechanobiology of Early Mammalian Development through Bioengineered Models. Dev Cell 2019; 48:751-763. [PMID: 30913407 DOI: 10.1016/j.devcel.2019.02.024] [Citation(s) in RCA: 60] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2018] [Revised: 01/13/2019] [Accepted: 02/26/2019] [Indexed: 12/21/2022]
Abstract
Research in developmental biology has been recently enriched by a multitude of in vitro models recapitulating key milestones of mammalian embryogenesis. These models obviate the challenge posed by the inaccessibility of implanted embryos, multiply experimental opportunities, and favor approaches traditionally associated with organoids and tissue engineering. Here, we provide a perspective on how these models can be applied to study the mechano-geometrical contributions to early mammalian development, which still escape direct verification in species that develop in utero. We thus outline new avenues for robust and scalable perturbation of geometry and mechanics in ways traditionally limited to non-implanting developmental models.
Collapse
Affiliation(s)
- Stefano Vianello
- Laboratory of Stem Cell Bioengineering, Institute of Bioengineering, School of Life Sciences (SV) and School of Engineering (STI), Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland.
| | - Matthias P Lutolf
- Laboratory of Stem Cell Bioengineering, Institute of Bioengineering, School of Life Sciences (SV) and School of Engineering (STI), Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland; Institute of Chemical Sciences and Engineering, School of Basic Science (SB), EPFL, Lausanne, Switzerland.
| |
Collapse
|