Heterogeneous pools of adult neural stem cells (NSCs) contribute to brain maintenance and regeneration after injury. The balance of NSC activation and quiescence, as well as the induction of lineage-specific transcription factors, may contribute to diversity of neuronal and glial fates. To identify molecular hallmarks governing these characteristics, we performed single-cell sequencing of an unbiased pool of adult subventricular zone NSCs. This analysis identified a discrete, dormant NSC subpopulation that already expresses distinct combinations of lineage-specific transcription factors during homeostasis. Dormant NSCs enter a primed-quiescent state before activation, which is accompanied by downregulation of glycolytic metabolism, Notch, and BMP signaling and a concomitant upregulation of lineage-specific transcription factors and protein synthesis. In response to brain ischemia, interferon gamma signaling induces dormant NSC subpopulations to enter the primed-quiescent state. This study unveils general principles underlying NSC activation and lineage priming and opens potential avenues for regenerative medicine in the brain. Overall design: Single cell RNAseq of cells isolated from their in vivo niche in the subventricular zone, Striatum and Cortex during homeostasis as well as following ischemic injury. In total 272 single cells. (<WT>: homeostasis samples; <Ischemic_injured> and <Ischemic_injured_and_Interferon_gamma_knockout>: samples following ischemic injuried).
Single-Cell Transcriptomics Reveals a Population of Dormant Neural Stem Cells that Become Activated upon Brain Injury.
No sample metadata fields
View SamplesHeterogeneity of meningeal cortical cells was deciphered on the molecular level using single cell RNA seq Overall design: RNA sequencing of 179 meningeal cortical cells isolated from naive wild-type mice
Neurogenic Radial Glia-like Cells in Meninges Migrate and Differentiate into Functionally Integrated Neurons in the Neonatal Cortex.
Sex, Specimen part, Subject
View SamplesSingle cell RNA-seq of neural stem cell and astrocytes from old mice Overall design: Single cell RNA-seq of neural stem cell and astrocytes from old mice
Quiescence Modulates Stem Cell Maintenance and Regenerative Capacity in the Aging Brain.
Sex, Age, Specimen part, Cell line, Subject
View SamplesIn this work we present the PrPC-dependent gene expression signature in N2A cells and its implication on the most overrepresented functions; cell cycle, cell growth and proliferation and cell morphology.
PrP(C) regulates epidermal growth factor receptor function and cell shape dynamics in Neuro2a cells.
Specimen part
View SamplesWe demonstrate that Prnp dosage is critical for the maintenance of neuronal homeostasis since both its absence and, more relevantly, its overexpression induce higher sensitivity to kainate (KA) damage. These data correlate with electrophysiological results in freely behaving mutant mice showing an imbalance in activity-dependent synaptic processes, as determined from input/output curves, paired-pulse facilitation, and LTP studies. Gene expression profiling showed that 129 genes involved in canonical pathways such as Ubiquitination or Neurotransmission among others were co-regulated in knockout and PrPc overexpressing mice. RT-qPCR analysis of neurotransmission-related genes confirmed GABA-A and AMPA-Kainate receptor subunit transcriptional co-regulation in both Prnp -/- and Tg20 mice. Our results demonstrate that PrPc is necessary for the proper homeostatic functioning of hippocampal circuits, because of its interactions with GABAA and AMPA-Kainate receptors.
Regulation of GABA(A) and glutamate receptor expression, synaptic facilitation and long-term potentiation in the hippocampus of prion mutant mice.
Sex
View SamplesWe have used an integrative high content analysis approach to identify the specific miRNAs implicated in EGF signaling in HeLa cells as potential mediators of cancer mediated functions. We have used microarray and deep-sequencing technologies in order to obtain a global view of the EGF miRNA transcriptome with a robust experimental cross-validation. By applying a procedure based on Rankprod tests, we have delimited a solid set of EGF-regulated miRNAs. After validating regulated miRNAs by RT-qPCR, we have derived protein networks and biological functions from the predicted targets of the regulated miRNAs to gain insight into the potential role of miRNAs in EGF-treated cells. In addition, we have analyzed sequence heterogeneity due to editing relative to the reference sequence (isomirs) among regulated miRNAs. Overall design: Time course experiment comparing HeLa gene expression in response to EGF analyzed by small RNA-seq using Illumina 36-bp read massively parallel sequencing. Three independent experiments were performed where HeLa cells were serum deprived for 24 hours and were either left untreated or treated with EGF for 6h and harvested for RNA extraction. Thus, a total of 6 samples were analyzed, 3 controls and the 3 respective treated counterparts. These same samples were also analyzed in parallel on two different microarray platforms.
Microarray and deep sequencing cross-platform analysis of the mirRNome and isomiR variation in response to epidermal growth factor.
Cell line, Subject
View SamplesEpidermal growth factor (EGF) is a key regulatory growth factor activating a myriad of processes affecting cell proliferation and survival that are relevant to normal development and disease. Here we have used a combined approach to study the EGF dependent transcriptome of HeLa cells. We obtained mRNA expression profiles using multiple long oligonucleotide based microarray platforms (from Agilent, Operon, Febit, and Illumina) in combination with digital gene expression profiling (DGE) with the Illumina Genome Analyzer I (GA-I). By applying a procedure for cross-platform data meta-analysis based on rank product and global ancova tests, we establish a well validated gene set with transcript levels altered after EGF treatment. We used this robust gene list to build higher order networks of gene interaction by interconnecting associated networks, supporting and extending the important role of the EGF signaling pathway in cancer. In addition, we found a whole new set of genes previously unrelated to the currently accepted EGF associated cellular functions, among which are metallothionein genes. We propose the use of global genomic cross-validation to generate more reliable datasets derived from high content technologies (microarrays or deep sequencing). This approach should help to improve the confidence of downstream in silico functional inference analyses based on high content data. Keywords: treated vs. untreated comparison, time course Overall design: Time course experiment comparing HeLa gene expression in response to EGF analyzed on different microarray platforms (Agilent, IMPPC, Illumina, and Operon) and by digital gene expression using short read high throughput tag sequencing. Three independent experiments were performed where HeLa cells were serum deprived for 24 hours and were either left untreated or treated with EGF for 6, and 24 h and harvested for RNA extraction. Technical dye swap duplicates were performed for each of the three biological replicates in both time points. Comparative genomic hybridization of HeLa cell genomic DNA versus poooled genomic DNA from blood obtained from human females conducted on commercial oligonucleotide microarrays (Human Genome CGH Microarray Kit 244A, Agilent Technologies) in order to assess DNA dosage dependence of gene expression levels and response to EGF. Digital gene expression using short read high throughput tag sequencing data submitted to NCBI''s SRA
Multiple platform assessment of the EGF dependent transcriptome by microarray and deep tag sequencing analysis.
No sample metadata fields
View SamplesSporadic Creutzfeldt-Jakob disease (sCJD) is the most prevalent form of human prion disease and it is characterized by the presence of neuronal loss, spongiform degeneration, chronic inflammation and the accumulation of misfolded and pathogenic prion protein (PrPSc). The molecular mechanisms underlying these alterations are largely unknown, but the presence of intracellular neuronal calcium (Ca+2) overload, a general feature in models of prion diseases, is suggested to play a key role in prion pathogenesis. Here we describe the presence of massive regulation of Ca+2 responsive genes in sCJD brain tissue, accompanied by two Ca+2-dependent processes: endoplasmic reticulum stress and the activation of the cysteine proteases Calpains 1/2. Pathogenic Calpain activation in sCJD is linked to the cleavage of their cellular substrates, impaired autophagy and lysosomal damage, which is partially reversed by Calpain inhibition in a cellular prion model. Calpain 1 treatment enhances seeding activity of PrPSc in a prion conversion assay. Neuronal lysosomal impairment caused by Calpain over activation leads to the release of the lysosomal protease Cathepsin S that in sCJD mainly localises in axons. Additionally, massive Cathepsin S overexpression is detected in microglial cells. Alterations in Ca+2 homeostasis and activation of Calpain-Cathepsin axis already occur at pre-clinical stages of the disease as detected in a humanized sCJD mouse model. Altogether our work indicates that unbalanced Calpain-Cathepsin activation is a relevant contributor to the pathogenesis of sCJD at multiple molecular levels and a potential target for therapeutic intervention. Overall design: To identify differentially expressed genes during development of sCJD pathology we analysed the expression levels in the cortical region of tg340-PRNP129MM mice infected with sCJD MM1 brain homogenates at pre-clinical (120 dpi) and clinical (180 dpi) stages.
Altered Ca<sup>2+</sup> homeostasis induces Calpain-Cathepsin axis activation in sporadic Creutzfeldt-Jakob disease.
Subject, Time
View SamplesCarcinoma development in colorectal cancer (CRC) is driven by genetic alterations in numerous signaling pathways. Alterations in the RAS-ERK1/2 pathway are associated with the shortest overall survival for patients after diagnosis of CRC metastatic disease, but how RAS-ERK signaling regulates CRC metastasis is still unknown.
ERK1/2 Signaling Induces Upregulation of ANGPT2 and CXCR4 to Mediate Liver Metastasis in Colon Cancer.
Cell line, Treatment
View SamplesThis SuperSeries is composed of the SubSeries listed below.
dKDM5/LID regulates H3K4me3 dynamics at the transcription-start site (TSS) of actively transcribed developmental genes.
Specimen part
View Samples