Project description:Here we extend our previous EMLO gastruloid technology to cardiac (EMLOC) with the generation of interconnected neuro-gut-cardiac interconnected multilineages. The contractile EMLOCs recapitulate numerous developmental features of heart tube formation and specialization, cardiomyocyte differentiation and remodeling phases, epicardium, ventricular wall morphogenesis, and formation of the putative outflow tract. Cardiogenesis in EMLOCs originates anterior to the gut tube primordium and we observe neurons that progressively populate the cardiogenic region in a pattern that mirrors the spatial distribution of neurons in heart innervation. The EMLOC mode represents the first multi-lineage advancement of neuro-cardiac lineages in a gastruloid model that parallels human cardiogenesis with neurogenesis.
Project description:Multi-lineage development from gastruloids is enabling unprecedented opportunities to model and study human embryonic processes and is expected to accelerate ex vivo strategies in organ development. Reproducing human cardiogenesis with neurogenesis in a multi-lineage context remains challenging, requiring spatiotemporal input of paracrine and mechanical cues. Here we extend elongating multi-lineage organized (EMLO) gastruloids to include cardiogenesis (EMLOC) and describe interconnected neuro-cardiac lineages in a single gastruloid model. Contractile EMLOCs recapitulate numerous interlinked developmental features including heart tube formation and specialization, cardiomyocyte differentiation and remodeling phases, epicardium, ventricular wall morphogenesis, chamber-like structures and formation of a putative outflow tract. The EMLOC cardiac region, which originates anterior to gut tube primordium, is progressively populated by neurons in a spatial pattern mirroring the known distribution of neurons in the innervated human heart. This human EMLOC model represents a multi-lineage advancement for the study of coincident neurogenesis and cardiogenesis.
Project description:Gata factors are amongst the genes expressed early on in the process of cardiogenesis. We used microarrays to examine the immediate early targets of Gata4 and Gata5 in the Xenopus leavis animal cap cardiogenesis model. We hope to use these data to examine the roles of Gata4 and Gata5 in cardiogenesis and also to begin to dissect out the common and distinct targets of Gata4 and Gata5. Experiment Overall Design: Xenopus leavis embryos were injected at the one cell stage with dexamethasone-inducible Gata4 or Gata5 mRNA constructs (to examine endodermal and mesodermal targets) or with Gata4 in the presence of Dkk1 (to examine mesodermal targets.) Embryos were cultured to stage 9, whereupon animal caps were excised and cultured for 2.5 hours in media containing dexamethasone to induce the constructs and cycloheximide to block de novo protein synthesis and thus give only immediate early targets.
Project description:Self-organisation and coordinated morphogenesis of multiple cardiac lineages is essential for the development and function of the heart1-3. However, the absence of a human in vitro model that mimics the basic lineage architecture of the heart hinders research into developmental mechanisms and congenital defects4. Here, we describe the establishment of a reliable, lineage-controlled and high-throughput cardiac organoid platform. We show that cardiac mesoderm derived from human pluripotent stem cells robustly self-organises and differentiates into cardiomyocytes forming a cavity. Co-differentiation of cardiomyocytes and endothelial cells from cardiac mesoderm within these structures is required to form a separate endothelial layer. As in vivo, the epicardium engulfs these cardiac organoids, migrates into the cardiomyocyte layer and differentiates. We use this model to demonstrate that cardiac cavity formation is controlled by a mesodermal WNT-BMP signalling axis. Disruption of one of the key BMP targets in cardiac mesoderm, the transcription factor HAND1, interferes with cavity formation, which is consistent with its role in early heart tube and left chamber development5. Thus, the cardiac organoid platform represents a powerful resource for the quantitative and mechanistic analysis of early human cardiogenesis and defects that are otherwise inaccessible. Beyond understanding congenital heart disease, cardiac organoids provide a foundation for future translational research into human cardiac disorders.
Project description:Non-coding RNAs regulate many biological processes including neurogenesis. The brain-enriched miR-124 is assigned as a key player of neuronal differentiation via its complex, but little understood, regulation of thousands of annotated targets. To systematically chart its regulatory functions, we used CRISPR/Cas9 gene editing to disrupt all six miR-124 alleles in human stem cells. Upon neuronal induction, miR-124-depleted cells underwent neurogenesis and became functional neurons, albeit with altered morphology and neurotransmitter specification. By RNA-induced-silencing-complex precipitation, we found that other miRNA species were upregulated in miR-124 depleted neurons. Furthermore, we identified 98 miR-124 targets of which some directly led to decreased viability. We performed advanced transcription-factor-network analysis and revealed indirect miR-124 effects on apoptosis and neuronal subtype differentiation. Our data emphasizes the need for combined experimental- and systems-level analyses to comprehensively disentangle and reveal miRNA functions, including their involvement in the neurogenesis of diverse neuronal cell types found in the human brain.
Project description:Non-coding RNAs regulate many biological processes including neurogenesis. The brain-enriched miR-124 is assigned as a key player of neuronal differentiation via its complex, but little understood, regulation of thousands of annotated targets. To systematically chart its regulatory functions, we used CRISPR/Cas9 gene editing to disrupt all six miR-124 alleles in human stem cells. Upon neuronal induction, miR-124-depleted cells underwent neurogenesis and became functional neurons, albeit with altered morphology and neurotransmitter specification. By RNA-induced-silencing-complex precipitation, we found that other miRNA species were upregulated in miR-124 depleted neurons. Furthermore, we identified 98 miR-124 targets of which some directly led to decreased viability. We performed advanced transcription-factor-network analysis and revealed indirect miR-124 effects on apoptosis and neuronal subtype differentiation. Our data emphasizes the need for combined experimental- and systems-level analyses to comprehensively disentangle and reveal miRNA functions, including their involvement in the neurogenesis of diverse neuronal cell types found in the human brain.
Project description:Non-coding RNAs regulate many biological processes including neurogenesis. The brain-enriched miR-124 is assigned as a key player of neuronal differentiation via its complex, but little understood, regulation of thousands of annotated targets. To systematically chart its regulatory functions, we used CRISPR/Cas9 gene editing to disrupt all six miR-124 alleles in human stem cells. Upon neuronal induction, miR-124-depleted cells underwent neurogenesis and became functional neurons, albeit with altered morphology and neurotransmitter specification. By RNA-induced-silencing-complex precipitation, we found that other miRNA species were upregulated in miR-124 depleted neurons. Furthermore, we identified 98 miR-124 targets of which some directly led to decreased viability. We performed advanced transcription-factor-network analysis and revealed indirect miR-124 effects on apoptosis and neuronal subtype differentiation. Our data emphasizes the need for combined experimental- and systems-level analyses to comprehensively disentangle and reveal miRNA functions, including their involvement in the neurogenesis of diverse neuronal cell types found in the human brain.
Project description:Non-coding RNAs regulate many biological processes including neurogenesis. The brain-enriched miR-124 is assigned as a key player of neuronal differentiation via its complex, but little understood, regulation of thousands of annotated targets. To systematically chart its regulatory functions, we used CRISPR/Cas9 gene editing to disrupt all six miR-124 alleles in human stem cells. Upon neuronal induction, miR-124-depleted cells underwent neurogenesis and became functional neurons, albeit with altered morphology and neurotransmitter specification. By RNA-induced-silencing-complex precipitation, we found that other miRNA species were upregulated in miR-124 depleted neurons. Furthermore, we identified 98 miR-124 targets of which some directly led to decreased viability. We performed advanced transcription-factor-network analysis and revealed indirect miR-124 effects on apoptosis and neuronal subtype differentiation. Our data emphasizes the need for combined experimental- and systems-level analyses to comprehensively disentangle and reveal miRNA functions, including their involvement in the neurogenesis of diverse neuronal cell types found in the human brain.