Project description:The data revealed differential expression between floor plate and ventral lateral region in E10.5 mouse embryo midbrain. Several differentially expressed genes in these regions have been reported in the literature, demonstrating reliability of tissue dissection. Midbrain floor plate and non-overlapping adjacent ventral lateral region of mouse E10.5 embryo midbrain was dissected. Each sample was a pool from 6 embryos. Three replicates for each region were used for the experiment.
Project description:The data revealed differential expression between floor plate and ventral lateral region in E10.5 mouse embryo midbrain. Several differentially expressed genes in these regions have been reported in the literature, demonstrating reliability of tissue dissection.
Project description:Regional specificity of stem cell-derived astrocytes is believed to be an important prerequisite for their applications in disease modelling and cell-based therapies. The regional identity of these astrocytes is often defined by the positional characteristics of their antecedent, stem cell-derived neural progenitors patterned to a fate of interest, with the assumption that the positional specification is to be preserved by the derived astrocytes. Using a human iPSC line designed for tracing midbrain floor plate derivatives, here we show that lineage composition of the derived astrocytes is not a faithful recapitulation of the founder progenitor population, as demonstrated by the loss of floor plate differentiated progeny in the final astrocyte products. Using deep single cell RNA sequencing, we identified distinct transcriptomic signatures of midbrain floor plate-derived astrocytes. Our study highlights the need for rigorous characterisation of PSC-derived regional astrocytes and provides a valuable resource for assessing midbrain floor plate-derived human astrocytes.
Project description:Embryonic stem (ES) cells were differentiated in culture to midbrain dopaminergic (mDA) progenitors and subjected to ChIP-seq analysis to resolve genome-wide binding sites of forkhead box protein A2 (Foxa2). Foxa2 was found to directly regulate multiple lineage pathways to specify midbrain dopaminergic and floor plate progenitor identity.
Project description:Organizers are specialized cell populations that orchestrate cell patterning and axon guidance in the developing nervous system. Although non-human models have led to fundamental discoveries about the organization of the nervous system midline by the floor plate, an experimental model of human floor plate would enable broader insights into regulation of human neurodevelopment and midline connectivity. Here, we have developed stem cell-derived organoids resembling human floor plate (hFpO) and assembled them with spinal cord organoids (hSpO) to generate midline assembloids (hMA). We demonstrate that hFpO promote Sonic hedgehog-dependent ventral patterning of human spinal progenitors and Netrin-dependent guidance of human commissural axons, paralleling non-human models. To investigate evolutionary-divergent midline regulators, we profiled the hFpO secretome and identified 27 evolutionarily divergent genes between human and mouse. Utilizing the hMA platform, we targeted these candidates in an arrayed CRISPR knockout screen and reveal that GALNT2, a gene involved in O-linked glycosylation, impairs floor plate-mediated guidance of commissural axons in humans. This novel platform extends prior axon guidance discoveries into human-specific neurobiology with implications for mechanisms of nervous system evolution and neurodevelopmental disorders.
Project description:Investigations into the roles for Pbx1 and its transcriptional network in dopaminergic neuron development and Parkinson's Disease Three samples each from dorsal midbrain, forebrain, hindbrain, Alar plate, and ventral midbrain
Project description:In the developing embryo, haematopoietic stem cells (HSCs) emerge from the aorta-gonad-mesonephros (AGM) region but the molecular regulation of this process is poorly understood. Recently, the progression from E9.5 to E10.5 and polarity along the dorso-ventral axis have been identified as clear demarcations of the supportive HSC niche. To identify novel secreted regulators of HSC maturation, we performed RNA-sequencing over these spatio-temporal transitions in the AGM region, and supportive OP9 cell line.
Project description:In the developing embryo, haematopoietic stem cells (HSCs) emerge from the aorta-gonad-mesonephros (AGM) region but the molecular regulation of this process is poorly understood. Recently, the progression from E9.5 to E10.5 and polarity along the dorso-ventral axis have been identified as clear demarcations of the supportive HSC niche. To identify novel secreted regulators of HSC maturation, we performed RNA-sequencing over these spatio-temporal transitions in the AGM region, and supportive OP9 cell line.
Project description:Floor plate-derived extracellular signaling molecules, including canonical axon guidance cues of the Netrin family, control neuronal circuit organization. Despite the importance of the floor plate as an essential signaling centre in the developing vertebrate central nervous system, no systematic approach to identify binding partners for floor plate-expressed cellsurface and secreted proteins has been carried out. Here, we used a high-throughput assay to discover extracellular protein-protein interactions, which likely take place in the zebrafish floor plate microenvironment. The assembled floor plate network contains 47 interactions including the hitherto not reported interaction between Netrin-1 and Draxin. We further characterized this interaction, narrowed down the binding interface, and demonstrated that Draxin competes with Netrin receptors for binding to Netrin-1. Our results suggest that Draxin functions as an extracellular Netrin signaling modulator in vertebrates. A reciprocal gradient of Draxin might shape or sharpen the active Netrin gradient, thereby critically modulating its effect.