It has been unclear whether ischemic stroke induces neurogenesis or neuronal DNA-rearrangements in the human neocortex. We show here that neither is the case, using immunohistochemistry, transcriptome-, genome- and ploidy-analyses, and determination of nuclear bomb test-derived 14C-concentration in neuronal DNA. A large proportion of cortical neurons display DNA-fragmentation and DNA-repair short time after stroke, whereas neurons at chronic stages after stroke show DNA-integrity, demonstrating the relevance of an intact genome for survival. Overall design: Analyze of potential fusion transcripts in 13 samples, seven cortical ischemic stroke tissue and six control cortex, by deep sequencing using Illumina HiSeq 2000
The age and genomic integrity of neurons after cortical stroke in humans.
No sample metadata fields
View Samplesin the present study, we evaluated whether microbiota modulation is able to restore hepatic steatosis induced by n-3 PUFA depletion in mice. For this purpose, mice were fed during three months with a n-3 PUFA-depleted diet (presenting a high n-6/n-3 PUFA ratio), and then supplemented with fructooligosaccharides (FOS, 0.25g/day/mice), a prebiotic, during the last ten days of the experiment (DEF/FOS). In the same time, some n-3 PUFA-depleted mice were returned on a control diet during the last 10 days of treatment (DEF/CT) to compare the effect of FOS supplementation to a restored intake in n-3 PUFA. Microarray analyses were performed to identify the molecular targets modified by FOS supplementation in the liver of n-3 PUFA depleted mice. These mice were compared to control mice (fed a control diet during the 112 days of experiment) and to n-3 PUFA-depleted mice (fed a n-3 PUFA-depleted diet during the 112 days of experiment) for which the results have been previously published (Pachikian B.D. et al. PLoS One. 2011;6(8):e23365, accession number GSE26986)
Prebiotic approach alleviates hepatic steatosis: implication of fatty acid oxidative and cholesterol synthesis pathways.
Sex, Specimen part, Treatment
View SamplesThe goal of this study is to determine gene expression changes in the adult zebrafish spinal cord at 2 weeks after complete transection. Overall design: 2 samples were analyzed in duplicates: sham injured spinal cord and transected spinal cord at 2 weeks post-injury
Injury-induced ctgfa directs glial bridging and spinal cord regeneration in zebrafish.
No sample metadata fields
View SamplesBy contrast with mammals, adult zebrafish have a high capacity to regenerate damaged or lost myocardium through proliferation of spared cardiomyocytes. The epicardial sheet covering the heart is activated by injury and aids muscle regeneration through paracrine effects and as a multipotent cell source, and has received recent attention as a target in cardiac repair strategies. While it is recognized that epicardium is required for muscle regeneration and itself has high regenerative potential, the extent of cellular heterogeneity within epicardial tissue is largely unexplored. In this study, we performed transcriptome analysis on dozens of epicardial lineage cells purified from zebrafish harboring a transgenic reporter for the pan-epicardial gene tcf21. Hierarchical clustering analysis suggested the presence of at least three epicardial cell subsets defined by expression signatures. We validated many new pan-epicardial and epicardial markers by alternative expression assays. Additionally, we explored the function of the scaffolding protein and main component of caveolae, caveolin-1 (cav1), which was present in each epicardial subset. In BAC transgenic zebrafish, cav1 regulatory sequences drove strong expression in ostensibly all epicardial cells and in coronary vascular endothelial cells. Moreover, cav1 mutant zebrafish generated by genome editing showed grossly normal heart development and adult cardiac anatomy, but displayed profound defects in injury-induced cardiomyocyte proliferation and heart regeneration. Our study defines a new platform for the discovery of epicardial lineage markers, genetic tools, and mechanisms of heart regeneration. Overall design: Deep sequencing of isolated single epicardial cells
Single epicardial cell transcriptome sequencing identifies Caveolin 1 as an essential factor in zebrafish heart regeneration.
Age, Specimen part, Cell line, Subject
View SamplesWe compared transcriptional profiles of regenerating zebrafish caudal fins following fin amputation with profiles from uninjured zebrafish caudal fins Overall design: Examination of whole fin transcriptional profiles from regenerating fins (2 pools of 10 fins) and uninjured fins (2 pools of 10 fins)
Modulation of tissue repair by regeneration enhancer elements.
No sample metadata fields
View SamplesWe compared transcriptional and chromatin profiles of regenerating zebrafish hearts following genetic ablation with profiles from uninjured zebrafish hearts. Overall design: Examination of whole heart transcriptional profiles from ablated hearts (2 pools of 10 hearts) and uninjured hearts (2 pools of 10 hearts). Examination of differential H3K27Ac marks following genetic ablation of cardiomyocytes (regenerating hearts) and uninjured hearts.
Modulation of tissue repair by regeneration enhancer elements.
No sample metadata fields
View SamplesCortistatin A (CA) is a highly selective inhibitor of the Mediator kinases CDK8 and CDK19. Using CA, we report here the first large-scale identification of Mediator kinase substrates in human cells (HCT116). Among over 16,000 quantified phosphosites, we identified 78 high-confidence Mediator kinase targets within 64 proteins, including DNA-binding transcription factors and proteins associated with chromatin, DNA repair, and RNA polymerase II. Although RNA-Seq data correlated with Mediator kinase targets, CA effects on gene expression were limited and distinct from CDK8 or CDK19 knockdown. Quantitative proteome analyses, which tracked about 7,000 proteins across six time points (0 – 24h), revealed that CA selectively affected pathways implicated in inflammation, growth, and metabolic regulation; contrary to expectations, increased turnover of Mediator kinase targets was not generally observed. Collectively, these data support Mediator kinases as regulators of chromatin and RNA polymerase II activity and suggest cellular roles beyond transcription, including metabolism and DNA repair. Overall design: HCT116 cells were treated with either 100nM CA or DMSO in biological triplicate for each population (6 samples total). Treatment was for 24h for compound and vehicle.
Identification of Mediator Kinase Substrates in Human Cells using Cortistatin A and Quantitative Phosphoproteomics.
No sample metadata fields
View SamplesWe report high-throughput profiling of gene expression from whole zebrafish ventricles. We profile mRNA in uninjured ventricles and those undergoing regeneration 14 days after genetic ablation. This study provides a framework for understanding transcriptional changes during adult models of regeneration. Overall design: Examination of gene expression in cardiomyocytes under different states of proliferation.
Resolving Heart Regeneration by Replacement Histone Profiling.
No sample metadata fields
View SamplesWe report global RNA expression profiles from whole zebrafish hearts 24 hours after ventricle amputation. Zebrafish were exposed to atropine or water following surgery.
Nerves Regulate Cardiomyocyte Proliferation and Heart Regeneration.
Specimen part, Treatment
View SamplesElevated levels of microRNA miR-155 represent a candidate pathogenic factor in chronic B-lymphocytic leukemia (B-CLL). In this study, we present evidence that MYB (v-myb myeloblastosis viral oncogene homolog) is overexpressed in a subset of B-CLL patients. MYB physically associates with the promoter of MIR155 host gene (MIR155HG, also known as BIC, B-cell integration cluster) and stimulates its transcription. This coincides with the hypermethylated histone H3K4 residue and spread hyperacetylation of H3K9 at MIR155HG promoter. Our data provide evidence of oncogenic activities of MYB in B-CLL that include its stimulatory role in MIR155HG transcription.
MYB transcriptionally regulates the miR-155 host gene in chronic lymphocytic leukemia.
Specimen part, Disease, Disease stage
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