Mechanics regulate human embryonic stem cell self-organization to specify mesoderm

AbstractEmbryogenesis is directed by morphogens that induce differentiation within a defined tissue geometry. Tissue organization is mediated by cell-cell and cell-extracellular matrix (ECM) adhesions and is modulated by cell tension and tissue-level force. Whether cell tension regulates development by directly influencing morphogen signaling remains unclear. Human embryonic stem cells (hESCs) exhibit an intrinsic capacity for self-organization that motivates their use as a tractable model of early human embryogenesis. We engineered patterned substrates that enhance cell-cell interactions to direct the self-organization of cultured hESCs into “gastrulation-like” nodes. Tissue geometries that generate local nodes of high cell-cell tension and induce these self-organized tissue nodes drive BMP4-dependent gastrulation by enhancing phosphorylation and nuclear translocation of β-catenin to promote Wnt signaling and mesoderm specification. The findings underscore the interplay between tissue organization, cell tension, and morphogen-dependent differentiation, and demonstrate that cell- and tissue-level forces directly regulate cell fate specification in early human development.Graphical AbstractHighlightsSubstrates that enhance cell-cell adhesion promote hESC self-organizationTissue nodes exhibiting high tension are predisposed to gastrulation inductionColony geometry dictates the localization of tension nodes to specify mesodermTension activates β-catenin and stimulates Wnt signaling to induce mesodermIn BriefEngineered substrates that promote cell-cell adhesion and reconstitute epiblast tissue organization facilitate “gastrulation-like” morphogenesis in cultured hESCs. Tissue geometries that foster localized regions of high cell-cell tension potentiate BMP4-dependent mesoderm specification by enhancing phosphorylation and nuclear translocation of β-catenin to promote Wnt signaling.

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Tet proteins influence the balance between neuroectodermal and mesodermal fate choice by inhibiting Wnt signaling

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1617802113 ◽

2016 ◽

Vol 113 (51) ◽

pp. E8267-E8276 ◽

Cited By ~ 42

Author(s):

Xiang Li ◽

Xiaojing Yue ◽

William A. Pastor ◽

Lizhu Lin ◽

Romain Georges ◽

...

Keyword(s):

Wnt Signaling ◽

Cell Fate ◽

Transcriptional Activation ◽

Ectopic Expression ◽

Embryonic Stem ◽

Mesodermal Cell ◽

Cell Fate Decisions ◽

Tet Proteins ◽

Mesoderm Specification ◽

Wnt Inhibitor

TET-family dioxygenases catalyze conversion of 5-methylcytosine (5mC) to 5-hydroxymethylcytosine (5hmC) and oxidized methylcytosines in DNA. Here, we show that mouse embryonic stem cells (mESCs), either lacking Tet3 alone or with triple deficiency of Tet1/2/3, displayed impaired adoption of neural cell fate and concomitantly skewed toward cardiac mesodermal fate. Conversely, ectopic expression of Tet3 enhanced neural differentiation and limited cardiac mesoderm specification. Genome-wide analyses showed that Tet3 mediates cell-fate decisions by inhibiting Wnt signaling, partly through promoter demethylation and transcriptional activation of the Wnt inhibitor secreted frizzled-related protein 4 (Sfrp4). Tet1/2/3-deficient embryos (embryonic day 8.0–8.5) showed hyperactivated Wnt signaling, as well as aberrant differentiation of bipotent neuromesodermal progenitors (NMPs) into mesoderm at the expense of neuroectoderm. Our data demonstrate a key role for TET proteins in modulating Wnt signaling and establishing the proper balance between neural and mesodermal cell fate determination in mouse embryos and ESCs.

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Enhanced Waddington landscape model with cell–cell communication can explain molecular mechanisms of self-organization

Bioinformatics ◽

10.1093/bioinformatics/btz201 ◽

2019 ◽

Vol 35 (20) ◽

pp. 4081-4088

Author(s):

Hosein Fooladi ◽

Parsa Moradi ◽

Ali Sharifi-Zarchi ◽

Babak Hosein Khalaj

Keyword(s):

Molecular Mechanisms ◽

Embryonic Stem ◽

Cell Communication ◽

Self Organization ◽

Supplementary Information ◽

Embryonic Cells ◽

Human Escs ◽

Germ Layers ◽

Cell Cell

Abstract Motivation The molecular mechanisms of self-organization that orchestrate embryonic cells to create astonishing patterns have been among major questions of developmental biology. It is recently shown that embryonic stem cells (ESCs), when cultured in particular micropatterns, can self-organize and mimic the early steps of pre-implantation embryogenesis. A systems-biology model to address this observation from a dynamical systems perspective is essential and can enhance understanding of the phenomenon. Results Here, we propose a multicellular mathematical model for pattern formation during in vitro gastrulation of human ESCs. This model enhances the basic principles of Waddington epigenetic landscape with cell–cell communication, in order to enable pattern and tissue formation. We have shown the sufficiency of a simple mechanism by using a minimal number of parameters in the model, in order to address a variety of experimental observations such as the formation of three germ layers and trophectoderm, responses to altered culture conditions and micropattern diameters and unexpected spotted forms of the germ layers under certain conditions. Moreover, we have tested different boundary conditions as well as various shapes, observing that the pattern is initiated from the boundary and gradually spreads towards the center. This model provides a basis for in-silico modeling of self-organization. Availability and implementation https://github.com/HFooladi/Self_Organization. Supplementary information Supplementary data are available at Bioinformatics online.

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Optogenetic control of Wnt signaling for modeling early embryogenic patterning with human pluripotent stem cells

10.1101/665695 ◽

2019 ◽

Cited By ~ 6

Author(s):

Nicole A. Repina ◽

Xiaoping Bao ◽

Joshua A. Zimmermann ◽

David A. Joy ◽

Ravi S. Kane ◽

...

Keyword(s):

Stem Cells ◽

Wnt Signaling ◽

Pluripotent Stem Cells ◽

High Efficiency ◽

Dynamic Range ◽

Embryonic Stem ◽

Human Pluripotent Stem Cells ◽

Self Organization ◽

Human Escs ◽

Mesenchymal Transition

ABSTRACTThe processes of cell proliferation, differentiation, migration, and self-organization during early embryonic development are governed by dynamic, spatially and temporally varying morphogen signals. Analogous tissue patterns emerge spontaneously in embryonic stem cell (ESC) models for gastrulation, but mechanistic insight into this self-organization is limited by a lack of molecular methods to precisely control morphogen signal dynamics. Here we combine optogenetic stimulation and single-cell imaging approaches to study self-organization of human pluripotent stem cells. Precise control of morphogen signal dynamics, achieved through activation of canonical Wnt/β-catenin signaling over a broad high dynamic range (>500-fold) using an optoWnt optogenetic system, drove broad transcriptional changes and mesendoderm differentiation of human ESCs at high efficiency (>95% cells). Furthermore, activating Wnt signaling in subpopulations of ESCs in 2D and 3D cultures induced cell self-organization and morphogenesis reminiscent of human gastrulation, including changes in cell migration and epithelial to mesenchymal transition. Our findings thus reveal an instructive role for Wnt in directing cell patterning in this ESC model for gastrulation.

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ER71 specifies Flk-1+ hemangiogenic mesoderm by inhibiting cardiac mesoderm and Wnt signaling

Blood ◽

10.1182/blood-2012-01-403766 ◽

2012 ◽

Vol 119 (14) ◽

pp. 3295-3305 ◽

Cited By ~ 54

Author(s):

Fang Liu ◽

Inyoung Kang ◽

Changwon Park ◽

Li-Wei Chang ◽

Wei Wang ◽

...

Keyword(s):

Stem Cells ◽

Endothelial Cell ◽

Embryonic Stem Cells ◽

Wnt Signaling ◽

Wnt Signaling Pathway ◽

Embryonic Stem ◽

Cell Lineage ◽

Mesoderm Specification ◽

In The Wild ◽

Ets Transcription Factor

Abstract Two distinct types of Flk-1+ mesoderm, hemangiogenic and cardiogenic, are thought to contribute to blood, vessel, and cardiac cell lineages. However, our understanding of how Flk-1+ mesoderm is specified is currently limited. In the present study, we investigated whether ER71, an Ets transcription factor essential for hematopoietic and endothelial cell lineage development, could modulate the hemangiogenic or cardiogenic outcome of the Flk-1+ mesoderm. We show that Flk-1+ mesoderm can be divided into Flk-1+PDGFRα− hemangiogenic and Flk-1+PDGFRα+ cardiogenic mesoderm. ER71-deficient embryonic stem cells produced only the Flk-1+PDGFRα+ cardiogenic mesoderm, which generated SMCs and cardiomyocytes. Enforced ER71 expression in the wild-type embryonic stem cells skewed toward the Flk-1+PDGFRα− mesoderm formation, which generated hematopoietic and endothelial cells. Whereas hematopoietic and endothelial cell genes were positively regulated by ER71, cardiac and Wnt signaling pathway genes were negatively regulated by ER71. We show that ER71 could inhibit Wnt signaling in VE-cadherin–independent as well as VE-cadherin–dependent VE-cadherin/β-catenin/Flk-1 complex formation. Enforced β-catenin could rescue cardiogenic mesoderm in the context of ER71 overexpression. In contrast, ER71-deficient Flk-1+ mesoderm displayed enhanced Wnt signaling, which was reduced by ER71 re-introduction. We provide the molecular basis for the antagonistic relationship between hemangiogenic and cardiogenic mesoderm specification by ER71 and Wnt signaling.

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Enhanced Waddington Landscape Model with Cell-Cell Communication Can Explain Molecular Mechanisms of Self-Organization

10.1101/241604 ◽

2018 ◽

Author(s):

H. Fooladi ◽

P. Moradi ◽

A. Sharifi-Zarchi ◽

B. H. Khalaj

Keyword(s):

Molecular Mechanisms ◽

Embryonic Stem ◽

Cell Communication ◽

Culture Conditions ◽

Self Organization ◽

Embryonic Cells ◽

Human Escs ◽

Germ Layers ◽

Cell Cell

AbstractThe molecular mechanisms of self-organization that orchestrate embryonic cells to create astonishing patterns have been among major questions of developmental biology. It is recently shown that embryonic stem cells (ESCs), when cultured on particular micropatterns, can self-organize and mimic early steps of pre-implantation embryogenesis. A systems-biology model to address this observation from a dynamical systems perspective is essential. Here, we propose a multicellular mathematical model for pattern formation during in vitro gastrulation of human ESCs. This model enhances the basic principles of Waddington epigenetic landscape with cell-cell communication, in order to enable pattern and tissue formation. To prevent overfitting of the model, there is a minimal number of parameters in the model, which are sufficient to address different experimental observations such as the formation of three germ layers and trophectoderm, responses to altered culture conditions and micropattern diameters, and unexpected spotted forms of the germ layers under certain conditions. This model provides a basis for in-silico modeling of self-organization.

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Faculty Opinions recommendation of Maintenance of pluripotency in human and mouse embryonic stem cells through activation of Wnt signaling by a pharmacological GSK-3-specific inhibitor.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.1016828.204353 ◽

2004 ◽

Author(s):

Gerald Spangrude

Keyword(s):

Stem Cells ◽

Embryonic Stem Cells ◽

Wnt Signaling ◽

Embryonic Stem ◽

Specific Inhibitor ◽

Mouse Embryonic Stem Cells ◽

Human And Mouse

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Hierarchical modeling of mechano-chemical dynamics of epithelial sheets across cells and tissue

Scientific Reports ◽

10.1038/s41598-021-83396-6 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Yoshifumi Asakura ◽

Yohei Kondo ◽

Kazuhiro Aoki ◽

Honda Naoki

Keyword(s):

Wound Healing ◽

Cell Migration ◽

Continuum Model ◽

Tissue Level ◽

Chemical Signals ◽

Cellular Level ◽

Mathematical Framework ◽

Collective Cell Migration ◽

The Continuum ◽

Cell Cell

AbstractCollective cell migration is a fundamental process in embryonic development and tissue homeostasis. This is a macroscopic population-level phenomenon that emerges across hierarchy from microscopic cell-cell interactions; however, the underlying mechanism remains unclear. Here, we addressed this issue by focusing on epithelial collective cell migration, driven by the mechanical force regulated by chemical signals of traveling ERK activation waves, observed in wound healing. We propose a hierarchical mathematical framework for understanding how cells are orchestrated through mechanochemical cell-cell interaction. In this framework, we mathematically transformed a particle-based model at the cellular level into a continuum model at the tissue level. The continuum model described relationships between cell migration and mechanochemical variables, namely, ERK activity gradients, cell density, and velocity field, which could be compared with live-cell imaging data. Through numerical simulations, the continuum model recapitulated the ERK wave-induced collective cell migration in wound healing. We also numerically confirmed a consistency between these two models. Thus, our hierarchical approach offers a new theoretical platform to reveal a causality between macroscopic tissue-level and microscopic cellular-level phenomena. Furthermore, our model is also capable of deriving a theoretical insight on both of mechanical and chemical signals, in the causality of tissue and cellular dynamics.

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Coordination of sonic hedgehog and Wnt signaling determines ventral and dorsal telencephalic neuron types from human embryonic stem cells

Development ◽

10.1242/dev.036624 ◽

2009 ◽

Vol 136 (23) ◽

pp. 4055-4063 ◽

Cited By ~ 199

Author(s):

X.-J. Li ◽

X. Zhang ◽

M. A. Johnson ◽

Z.-B. Wang ◽

T. LaVaute ◽

...

Keyword(s):

Stem Cells ◽

Embryonic Stem Cells ◽

Wnt Signaling ◽

Sonic Hedgehog ◽

Human Embryonic Stem Cells ◽

Embryonic Stem

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Maturation of Embryonic Stem Cells Into Endothelial Cells in an In Vitro Model of Vasculogenesis

Blood ◽

10.1182/blood.v93.4.1253.404k31_1253_1263 ◽

1999 ◽

Vol 93 (4) ◽

pp. 1253-1263 ◽

Cited By ~ 5

Author(s):

Masanori Hirashima ◽

Hiroshi Kataoka ◽

Satomi Nishikawa ◽

Norihisa Matsuyoshi ◽

Shin-Ichi Nishikawa

Keyword(s):

Cell Adhesion ◽

Endothelial Cell ◽

Growth Factor ◽

Culture System ◽

Molecular Mechanisms ◽

Es Cells ◽

Embryonic Stem ◽

Vascular Endothelial ◽

Cell Cell

A primitive vascular plexus is formed through coordinated regulation of differentiation, proliferation, migration, and cell-cell adhesion of endothelial cell (EC) progenitors. In this study, a culture system was devised to investigate the behavior of purified EC progenitors in vitro. Because Flk-1+ cells derived from ES cells did not initially express other EC markers, they were sorted and used as EC progenitors. Their in vitro differentiation into ECs, via vascular endothelial-cadherin (VE-cadherin)+ platelet-endothelial cell adhesion molecule-1 (PECAM-1)+ CD34−to VE-cadherin+ PECAM-1+CD34+ stage, occurred without exogenous factors, whereas their proliferation, particularly at low cell density, required OP9 feeder cells. On OP9 feeder layer, EC progenitors gave rise to sheet-like clusters of Flk-1+ cells, with VE-cadherin concentrated at the cell-cell junction. The growth was suppressed by Flt-1-IgG1 chimeric protein and dependent on vascular endothelial growth factor (VEGF) but not placenta growth factor (PIGF). Further addition of VEGF resulted in cell dispersion, indicating the role of VEGF in the migration of ECs as well as their proliferation. Cell-cell adhesion of ECs in this culture system was mediated by VE-cadherin. Thus, the culture system described here is useful in dissecting the cellular events of EC progenitors that occur during vasculogenesis and in investigating the molecular mechanisms underlying these processes.

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