Cell fate specification relies on the action of critical transcription factors that become available at distinct stages of embryonic development. One such factor is NeuroD1, which is essential for eliciting the neuronal development program and possesses the ability to reprogram other cell types into neurons. Given this capacity, it is important to understand its targets and the mechanism underlying neuronal specification. Here, we show that NeuroD1 directly binds regulatory elements of neuronal genes that are developmentally silenced by epigenetic mechanisms. This targeting is sufficient to initiate events that confer transcriptional competence, including reprogramming of transcription factor landscape, conversion of heterochromatin to euchromatin and increased chromatin accessibility, indicating potential pioneer factor ability of NeuroD1. The transcriptional induction of neuronal fate genes is maintained via epigenetic memory despite a transient NeuroD1 induction during neurogenesis. Our study not only reveals the NeuroD1-dependent gene regulatory program driving neurogenesis but also increases our understanding of how cell-fate specification during development involves a concerted action of transcription factors and epigenetic mechanisms. Overall design: 1. Ectopic NeuroD1 was induced for 48 hours (+Dox) in ES cells for checking initiation of neuronal transcriptional program in comparison to uninduced condition (-Dox) 2. ChIP-seq was performed after 24 hours of NeuroD1 induction in ES cells.
NeuroD1 reprograms chromatin and transcription factor landscapes to induce the neuronal program.
No sample metadata fields
View SamplesTranscriptome analysis of somatic stem cells and their progeny is fundamental to identify new factors controlling proliferation versus differentiation during tissue formation. Here we generated a combinatorial, fluorescent reporter mouse line to isolate proliferating neural stem cells, differentiating progenitors and newborn neurons that coexist as intermingled cell populations during brain development. Transcriptome sequencing revealed numerous novel long non-coding (lnc)RNAs and uncharacterized protein-coding transcripts identifying the signature of neurogenic commitment. Importantly, most lncRNAs overlapped neurogenic genes and shared with them a nearly identical expression pattern suggesting that lncRNAs control corticogenesis by tuning the expression of nearby cell fate determinants. We assessed the power of our approach by manipulating lncRNAs and protein-coding transcripts with no function in corticogenesis reported to date. This led to several evident phenotypes in neurogenic commitment and neuronal survival indicating that our study provides a remarkably high number of uncharacterized transcripts with hitherto unsuspected roles in brain development. Finally, we focussed on one lncRNA, Miat, whose manipulation was found to trigger pleiotropic effects on brain development and aberrant splicing of Wnt7b. Hence, our study suggests that lncRNA-mediated alternative splicing of cell fate determinants controls stem cell commitment during neurogenesis. “LncRNAs control neurogenesis” Aprea, Prenninger, Dori, Monasor, Wessendof, Zocher, Massalini, Ghosh, Alexopoulou, Lesche, Dahl, Groszer, Hiller, Calegari, The EMBO Journal (In Press) Overall design: mRNA profiles of Proliferating Progenitors, Differentiating Progenitors and Neurons from lateral cortex of E14.5 mouse embryos. Each cell type in three biological replicates.
Transcriptome sequencing during mouse brain development identifies long non-coding RNAs functionally involved in neurogenic commitment.
No sample metadata fields
View SamplesIn addition to the recently published in situ transcriptomics of LCL skin lesions (Novais et al., Khouri et al.), we herein present the first systemic disease signature of localized cutaneous leishmaniasis (LCL), using Affymetrix microarrays (HuGene 1.0) followed by systems biology analysis of the PBMC transciptome of LCL patients (n=18), as compared to healthy controls (n=12).
Systems Approach Reveals Nuclear Factor Erythroid 2-Related Factor 2/Protein Kinase R Crosstalk in Human Cutaneous Leishmaniasis.
Specimen part, Disease stage
View SamplesThis SuperSeries is composed of the SubSeries listed below.
MicroRNAs establish robustness and adaptability of a critical gene network to regulate progenitor fate decisions during cortical neurogenesis.
Specimen part
View SamplesDuring cortical development neurons are generated sequentially from basal progenitors (BPs) which specifically express the transcription factor Tbr2. We used fluorescent-activaed cell sorting (FACS) to isolate BPs from Tbr2GFP knockin reporter mice (Arnold SJ et al. Genesis, 2009) at early (embryonic day, E13) and late (embryonic day, E16) stages of cortical neurogenesis and determined mRNA expression profiles using mouse mRNA microarray (Illumina MouseWG-6 v2). Comparison of E13 and E16 mRNA expression profiles allowed us to identify regulatory gene networks for maintaining stage specific homeostasis of BPs throughout neurogenesis.
MicroRNAs establish robustness and adaptability of a critical gene network to regulate progenitor fate decisions during cortical neurogenesis.
Specimen part
View SamplesTranscriptome study of 2 Saccharomyces cerevisiae W303 derivatives, one carrying GFP (control) and one carrying aSyn-GFP
Different 8-hydroxyquinolines protect models of TDP-43 protein, α-synuclein, and polyglutamine proteotoxicity through distinct mechanisms.
Specimen part, Disease, Cell line
View SamplesThe MaxiK potassium channel is a key modulator of smooth muscle tone. Due to its calcium and voltage sensitivity, MaxiK is activated following depolarization and Ca2+ mobilization, therefore relaxing the muscle. We investigate the effects of silencing MaxiK for 48h in corpus cavernosuml smooth muscle (CCSM) cells to identify possible mechanisms of compensation through molecular crosstalk between pathways regulating smooth muscle tone.
Silencing MaxiK activity in corporal smooth muscle cells initiates compensatory mechanisms to maintain calcium homeostasis.
Specimen part
View SamplesThe discovery of significant heterogeneity in the self-renewal durability of adult haematopoietic stem cells (HSCs) has challenged our understanding of the molecules involved in population maintenance throughout life. Gene expression studies in bulk populations are difficult to interpret since multiple HSC subtypes are present and HSC purity is typically less than 50% of the input cell population. Numerous groups have therefore turned to studying gene expression profiles of single HSCs, but again these studies are limited by the purity of the input fraction and an inability to directly ascribe a molecular program to a durable self-renewing HSC. Here we combine single cell functional assays with flow cytometric index sorting and single cell gene expression assays to gain the first insight into the gene expression program of HSCs that possess durable self-renewal. This approach can be used in other stem cell systems and sets the stage for linking key molecules with defined cellular functions. Overall design: single-cell RNA-Seq of haematopoietic stem cells
Combined Single-Cell Functional and Gene Expression Analysis Resolves Heterogeneity within Stem Cell Populations.
No sample metadata fields
View SamplesEnteroendocrine L-cells release hormones that control metabolism and appetite and are targets under investigation for the treatment of diabetes and obesity. Understanding L-cell diversity and expression profiles is critical for identifying target receptors that will translate into altered hormone secretion. We performed single cell RNA sequencing of mouse L-cells from the upper small intestine to distinguish cellular populations, revealing that L-cells form 3 major clusters: a group with typical characteristics of classical L-cells, including high expression of Gcg and Pyy; a cell type overlapping with Gip-expressing K-cells; and a unique cluster expressing Tph1 and Pzp that was predominantly located in duodenal villi and co-produced 5HT. Expression of G-protein coupled receptors differed between clusters, suggesting the cell types are differentially regulated, and would be differentially targetable. Our findings support the emerging concept that many enteroendocrine cell populations are highly overlapping, with individual cells producing a range of peptides previously assigned to distinct cell types. Overall design: Single cell RNA sequencing of mouse duodenal L-cells cells
Single-cell RNA-sequencing reveals a distinct population of proglucagon-expressing cells specific to the mouse upper small intestine.
Specimen part, Subject
View SamplesTo identify the molecular characterisitics of parallel lineage-biased MPP populations arising from hematopoietic stem cells (HSC) we conducted genome-wide analyses of hematopoietic stem, progenitor and mature myeloid cell populations using Affymetrix Gene ST1.0 arrays.
Functionally Distinct Subsets of Lineage-Biased Multipotent Progenitors Control Blood Production in Normal and Regenerative Conditions.
Specimen part
View Samples