-
Nature Sep 2021Signals from sympathetic neurons and immune cells regulate adipocytes and thereby contribute to fat tissue biology. Interactions between the nervous and immune systems...
Signals from sympathetic neurons and immune cells regulate adipocytes and thereby contribute to fat tissue biology. Interactions between the nervous and immune systems have recently emerged as important regulators of host defence and inflammation. Nevertheless, it is unclear whether neuronal and immune cells co-operate in brain-body axes to orchestrate metabolism and obesity. Here we describe a neuro-mesenchymal unit that controls group 2 innate lymphoid cells (ILC2s), adipose tissue physiology, metabolism and obesity via a brain-adipose circuit. We found that sympathetic nerve terminals act on neighbouring adipose mesenchymal cells via the β2-adrenergic receptor to control the expression of glial-derived neurotrophic factor (GDNF) and the activity of ILC2s in gonadal fat. Accordingly, ILC2-autonomous manipulation of the GDNF receptor machinery led to alterations in ILC2 function, energy expenditure, insulin resistance and propensity to obesity. Retrograde tracing and chemical, surgical and chemogenetic manipulations identified a sympathetic aorticorenal circuit that modulates ILC2s in gonadal fat and connects to higher-order brain areas, including the paraventricular nucleus of the hypothalamus. Our results identify a neuro-mesenchymal unit that translates cues from long-range neuronal circuitry into adipose-resident ILC2 function, thereby shaping host metabolism and obesity.
Topics: Adipose Tissue; Animals; Brain; Cues; Cytokines; Energy Metabolism; Female; Glial Cell Line-Derived Neurotrophic Factor; Gonads; Immunity, Innate; Mesoderm; Mice; Mice, Inbred C57BL; Neural Pathways; Neurons; Obesity; Paraventricular Hypothalamic Nucleus; Proto-Oncogene Proteins c-ret; Receptors, Adrenergic, beta-2; Sympathetic Nervous System
PubMed: 34408322
DOI: 10.1038/s41586-021-03830-7 -
Nature Dec 2022Our understanding of human early development is severely hampered by limited access to embryonic tissues. Due to their close evolutionary relationship with humans,...
Our understanding of human early development is severely hampered by limited access to embryonic tissues. Due to their close evolutionary relationship with humans, nonhuman primates are often used as surrogates to understand human development but currently suffer from a lack of in vivo datasets, especially from gastrulation to early organogenesis during which the major embryonic cell types are dynamically specified. To fill this gap, we collected six Carnegie stage 8-11 cynomolgus monkey (Macaca fascicularis) embryos and performed in-depth transcriptomic analyses of 56,636 single cells. Our analyses show transcriptomic features of major perigastrulation cell types, which help shed light on morphogenetic events including primitive streak development, somitogenesis, gut tube formation, neural tube patterning and neural crest differentiation in primates. In addition, comparative analyses with mouse embryos and human embryoids uncovered conserved and divergent features of perigastrulation development across species-for example, species-specific dependency on Hippo signalling during presomitic mesoderm differentiation-and provide an initial assessment of relevant stem cell models of human early organogenesis. This comprehensive single-cell transcriptome atlas not only fills the knowledge gap in the nonhuman primate research field but also serves as an invaluable resource for understanding human embryogenesis and developmental disorders.
Topics: Animals; Humans; Mice; Gastrulation; Macaca fascicularis; Organogenesis; Single-Cell Analysis; Embryoid Bodies; Gene Expression Profiling; Primitive Streak; Neural Tube; Neural Crest; Hippo Signaling Pathway; Mesoderm; Stem Cells
PubMed: 36517595
DOI: 10.1038/s41586-022-05526-y -
Cell Jun 2023The hourglass model describes the convergence of species within the same phylum to a similar body plan during development; however, the molecular mechanisms underlying...
The hourglass model describes the convergence of species within the same phylum to a similar body plan during development; however, the molecular mechanisms underlying this phenomenon in mammals remain poorly described. Here, we compare rabbit and mouse time-resolved differentiation trajectories to revisit this model at single-cell resolution. We modeled gastrulation dynamics using hundreds of embryos sampled between gestation days 6.0 and 8.5 and compared the species using a framework for time-resolved single-cell differentiation-flows analysis. We find convergence toward similar cell-state compositions at E7.5, supported by the quantitatively conserved expression of 76 transcription factors, despite divergence in surrounding trophoblast and hypoblast signaling. However, we observed noticeable changes in specification timing of some lineages and divergence of primordial germ cell programs, which in the rabbit do not activate mesoderm genes. Comparative analysis of temporal differentiation models provides a basis for studying the evolution of gastrulation dynamics across mammals.
Topics: Animals; Rabbits; Mice; Gastrulation; Mesoderm; Cell Differentiation; Mammals; Trophoblasts; Gene Expression Regulation, Developmental
PubMed: 37209682
DOI: 10.1016/j.cell.2023.04.037 -
Nature Feb 2023The vertebrate body displays a segmental organization that is most conspicuous in the periodic organization of the vertebral column and peripheral nerves. This metameric...
The vertebrate body displays a segmental organization that is most conspicuous in the periodic organization of the vertebral column and peripheral nerves. This metameric organization is first implemented when somites, which contain the precursors of skeletal muscles and vertebrae, are rhythmically generated from the presomitic mesoderm. Somites then become subdivided into anterior and posterior compartments that are essential for vertebral formation and segmental patterning of the peripheral nervous system. How this key somitic subdivision is established remains poorly understood. Here we introduce three-dimensional culture systems of human pluripotent stem cells called somitoids and segmentoids, which recapitulate the formation of somite-like structures with anteroposterior identity. We identify a key function of the segmentation clock in converting temporal rhythmicity into the spatial regularity of anterior and posterior somitic compartments. We show that an initial 'salt and pepper' expression of the segmentation gene MESP2 in the newly formed segment is transformed into compartments of anterior and posterior identity through an active cell-sorting mechanism. Our research demonstrates that the major patterning modules that are involved in somitogenesis, including the clock and wavefront, anteroposterior polarity patterning and somite epithelialization, can be dissociated and operate independently in our in vitro systems. Together, we define a framework for the symmetry-breaking process that initiates somite polarity patterning. Our work provides a platform for decoding general principles of somitogenesis and advancing knowledge of human development.
Topics: Humans; Body Patterning; Cell Culture Techniques, Three Dimensional; In Vitro Techniques; Somites; Spine; Biological Clocks; Epithelium
PubMed: 36543321
DOI: 10.1038/s41586-022-05655-4 -
Nature Dec 2019Formation of the three primary germ layers during gastrulation is an essential step in the establishment of the vertebrate body plan and is associated with major...
Formation of the three primary germ layers during gastrulation is an essential step in the establishment of the vertebrate body plan and is associated with major transcriptional changes. Global epigenetic reprogramming accompanies these changes, but the role of the epigenome in regulating early cell-fate choice remains unresolved, and the coordination between different molecular layers is unclear. Here we describe a single-cell multi-omics map of chromatin accessibility, DNA methylation and RNA expression during the onset of gastrulation in mouse embryos. The initial exit from pluripotency coincides with the establishment of a global repressive epigenetic landscape, followed by the emergence of lineage-specific epigenetic patterns during gastrulation. Notably, cells committed to mesoderm and endoderm undergo widespread coordinated epigenetic rearrangements at enhancer marks, driven by ten-eleven translocation (TET)-mediated demethylation and a concomitant increase of accessibility. By contrast, the methylation and accessibility landscape of ectodermal cells is already established in the early epiblast. Hence, regulatory elements associated with each germ layer are either epigenetically primed or remodelled before cell-fate decisions, providing the molecular framework for a hierarchical emergence of the primary germ layers.
Topics: Animals; Cell Differentiation; Cell Lineage; Chromatin; DNA Methylation; Demethylation; Embryoid Bodies; Endoderm; Enhancer Elements, Genetic; Epigenesis, Genetic; Epigenome; Erythropoiesis; Factor Analysis, Statistical; Gastrula; Gastrulation; Gene Expression Regulation, Developmental; Mesoderm; Mice; Pluripotent Stem Cells; RNA; Single-Cell Analysis; Time Factors; Zinc Fingers
PubMed: 31827285
DOI: 10.1038/s41586-019-1825-8 -
Nature Feb 2023Cell identity is governed by the complex regulation of gene expression, represented as gene-regulatory networks. Here we use gene-regulatory networks inferred from...
Cell identity is governed by the complex regulation of gene expression, represented as gene-regulatory networks. Here we use gene-regulatory networks inferred from single-cell multi-omics data to perform in silico transcription factor perturbations, simulating the consequent changes in cell identity using only unperturbed wild-type data. We apply this machine-learning-based approach, CellOracle, to well-established paradigms-mouse and human haematopoiesis, and zebrafish embryogenesis-and we correctly model reported changes in phenotype that occur as a result of transcription factor perturbation. Through systematic in silico transcription factor perturbation in the developing zebrafish, we simulate and experimentally validate a previously unreported phenotype that results from the loss of noto, an established notochord regulator. Furthermore, we identify an axial mesoderm regulator, lhx1a. Together, these results show that CellOracle can be used to analyse the regulation of cell identity by transcription factors, and can provide mechanistic insights into development and differentiation.
Topics: Animals; Humans; Mice; Cell Differentiation; Embryonic Development; Gene Regulatory Networks; Phenotype; Transcription Factors; Zebrafish; Computer Simulation; Mesoderm; Hematopoiesis
PubMed: 36755098
DOI: 10.1038/s41586-022-05688-9 -
Biomedicine & Pharmacotherapy =... Oct 2019Endothelial-to-mesenchymal transition (EndMT) is closely related to the pathogenesis of various diseases, including cardiac fibrosis. Transforming growth factor...
Endothelial-to-mesenchymal transition (EndMT) is closely related to the pathogenesis of various diseases, including cardiac fibrosis. Transforming growth factor (TGF)-β1 strongly induces EndMT, and sirtuin 1 (SIRT1) may play vital roles in TGF-β/Smad pathway inhibition. This study aimed to determine whether SIRT1 activation inhibits EndMT, thereby attenuating cardiac fibrosis. Cardiac fibrosis was induced in C57BL/6 mice by subcutaneously injecting isoproterenol. SIRT1 was activated and then suppressed by intraperitoneally injecting resveratrol (RSV) and EX527, respectively. EndMT was induced by adding TGF-β1 to H5V cells and measured by immunofluorescence and western blot. The role of SIRT1 in EndMT was determined by lentivirus-mediated overexpression of SIRT1. Interactions between SIRT1 and Smad2/3 in the TGF-β/Smad2/3 pathway were examined by immunoprecipitation. SIRT1 activation upregulated CD31 and vascular endothelial-cadherin, and downregulated α-smooth muscle actin, fibroblast-specific protein 1, and vimentin. SIRT1 upregulated and EX527 inhibited TGF-β receptor 1 (TGF-βR1) and P-Smad2/3 expression, respectively. SIRT1 activation and overexpression by RSV/SRT2104 and lentivirus transfection, respectively, reduced TGF-β1-induced EndMT. SIRT1 and Smad2/3 interaction was shown by immunoprecipitation in vivo and in vitro. TGF-βR1 and P-Smad2/3 expression was downregulated and Smad2/3 nuclear translocation was inhibited. In conclusion, SIRT1 activated by RSV attenuated isoproterenol-induced cardiac fibrosis by regulating EndMT via the TGF-β/Smad2/3 pathway.
Topics: Animals; Cardiomegaly; Cell Line; Cell Nucleus; Collagen; Down-Regulation; Endothelium; Fibrosis; Isoproterenol; Male; Mesoderm; Mice, Inbred C57BL; Models, Biological; Myocardium; Phosphorylation; Protein Transport; Resveratrol; Sirtuin 1; Smad Proteins; Transforming Growth Factor beta
PubMed: 31351433
DOI: 10.1016/j.biopha.2019.109227 -
Cell Research Sep 2023Studies of cultured embryos have provided insights into human peri-implantation development. However, detailed knowledge of peri-implantation lineage development as well...
Studies of cultured embryos have provided insights into human peri-implantation development. However, detailed knowledge of peri-implantation lineage development as well as underlying mechanisms remains obscure. Using 3D-cultured human embryos, herein we report a complete cell atlas of the early post-implantation lineages and decipher cellular composition and gene signatures of the epiblast and hypoblast derivatives. In addition, we develop an embryo-like assembloid (E-assembloid) by assembling naive hESCs and extraembryonic cells. Using human embryos and E-assembloids, we reveal that WNT, BMP and Nodal signaling pathways synergistically, but functionally differently, orchestrate human peri-implantation lineage development. Specially, we dissect mechanisms underlying extraembryonic mesoderm and extraembryonic endoderm specifications. Finally, an improved E-assembloid is developed to recapitulate the epiblast and hypoblast development and tissue architectures in the pre-gastrulation human embryo. Our findings provide insights into human peri-implantation development, and the E-assembloid offers a useful model to disentangle cellular behaviors and signaling interactions that drive human embryogenesis.
Topics: Humans; Germ Layers; Embryo, Mammalian; Embryo Implantation; Endoderm; Mesoderm; Embryonic Development
PubMed: 37460804
DOI: 10.1038/s41422-023-00846-8 -
Nature Communications Aug 2022Cranial neural crest cells are an evolutionary innovation of vertebrates for craniofacial development and function, yet the mechanisms that govern the cell fate...
Cranial neural crest cells are an evolutionary innovation of vertebrates for craniofacial development and function, yet the mechanisms that govern the cell fate decisions of postmigratory cranial neural crest cells remain largely unknown. Using the mouse molar as a model, we perform single-cell transcriptome profiling to interrogate the cell fate diversification of postmigratory cranial neural crest cells. We reveal the landscape of transcriptional heterogeneity and define the specific cellular domains during the progression of cranial neural crest cell-derived dental lineage diversification, and find that each domain makes a specific contribution to distinct molar mesenchymal tissues. Furthermore, IGF signaling-mediated cell-cell interaction between the cellular domains highlights the pivotal role of autonomous regulation of the dental mesenchyme. Importantly, we reveal cell-type-specific gene regulatory networks in the dental mesenchyme and show that Foxp4 is indispensable for the differentiation of periodontal ligament. Our single-cell atlas provides comprehensive mechanistic insight into the cell fate diversification process of the cranial neural crest cell-derived odontogenic populations.
Topics: Animals; Cell Differentiation; Gene Expression Regulation, Developmental; Mesoderm; Mice; Morphogenesis; Neural Crest; Odontogenesis; Signal Transduction
PubMed: 35974052
DOI: 10.1038/s41467-022-32490-y -
Cell Feb 2023Axial development of mammals involves coordinated morphogenetic events, including axial elongation, somitogenesis, and neural tube formation. To gain insight into the...
Axial development of mammals involves coordinated morphogenetic events, including axial elongation, somitogenesis, and neural tube formation. To gain insight into the signals controlling the dynamics of human axial morphogenesis, we generated axially elongating organoids by inducing anteroposterior symmetry breaking of spatially coupled epithelial cysts derived from human pluripotent stem cells. Each organoid was composed of a neural tube flanked by presomitic mesoderm sequentially segmented into somites. Periodic activation of the somite differentiation gene MESP2 coincided in space and time with anteriorly traveling segmentation clock waves in the presomitic mesoderm of the organoids, recapitulating critical aspects of somitogenesis. Timed perturbations demonstrated that FGF and WNT signaling play distinct roles in axial elongation and somitogenesis, and that FGF signaling gradients drive segmentation clock waves. By generating and perturbing organoids that robustly recapitulate the architecture of multiple axial tissues in human embryos, this work offers a means to dissect mechanisms underlying human embryogenesis.
Topics: Animals; Humans; Body Patterning; Embryonic Development; Gene Expression Regulation, Developmental; Mammals; Mesoderm; Morphogenesis; Somites; Wnt Signaling Pathway; Organoids
PubMed: 36657441
DOI: 10.1016/j.cell.2022.12.042