Overall goal: To elucidate the endothelial-specific role of Gata4 signaling in endothelial maturation and vascular maintenance. Purpose of analysis: To generate a transcriptional profile of Gata4-deficient endothelial cells in the adult myocardium under homeostatic conditions. Overall design: Experimental structure: Transcriptional profile generated using RNAseq and differential gene expression analyses of endothelial cells lacking Gata4 isolated from healthy hearts.
Gata4-Dependent Differentiation of c-Kit<sup>+</sup>-Derived Endothelial Cells Underlies Artefactual Cardiomyocyte Regeneration in the Heart.
Specimen part, Subject
View SamplesCardiac fibroblasts convert to myofibroblasts with injury to mediate healing after acute myocardial infarction and to mediate long-standing fibrosis with chronic disease. Myofibroblasts remain a poorly defined cell-type in terms of their origins and functional effects in vivo. Methods: Here we generate Postn (periostin) gene-targeted mice containing a tamoxifen inducible Cre for cellular lineage tracing analysis. This Postn allele identifies essentially all myofibroblasts within the heart and multiple other tissues. Results: Lineage tracing with 4 additional Cre-expressing mouse lines shows that periostin-expressing myofibroblasts in the heart derive from tissue-resident fibroblasts of the Tcf21 lineage, but not endothelial, immune/myeloid or smooth muscle cells. Deletion of periostin+ myofibroblasts reduces collagen production and scar formation after myocardial infarction. Periostin-traced myofibroblasts also revert back to a less activated state upon injury resolution. Conclusions: Our results define the myofibroblast as a periostin-expressing cell-type necessary for adaptive healing and fibrosis in the heart, which arises from Tcf21+ tissue-resident fibroblasts. Overall design: Fluidigm C1 whole genome transcriptome analysis of lineage mapped cardiac myofibroblasts
Genetic lineage tracing defines myofibroblast origin and function in the injured heart.
Specimen part, Cell line, Subject
View SamplesThe lack of mouse models permitting the specific ablation of tissue-resident macrophages and monocyte-derived cells complicates understanding of their contribution to tissue integrity and to immune responses. Here we use a new model permitting diphtheria-toxin (DT)-mediated depletion of those cells and in which dendritic cells are spared. We showed that the myeloid cells of the mouse ear skin dermis are dominated by a population of melanin-laden macrophages, called melanophages, that has been missed in most previous studies. By using gene expression profiling, DT-mediated ablation and parabiosis, we determined their identity including their similarity to other skin macrophages, their origin and their dynamics. Limited information exist on the identity of the skin cells responsible for long-term tattoo persistence. Benefiting of our knowledge on melanophages, we showed that they are responsible for retaining tattoo pigment particles through a dynamic process which characterization has direct implications for improving strategies aiming at removing tattoos.
Unveiling skin macrophage dynamics explains both tattoo persistence and strenuous removal.
Specimen part, Treatment
View SamplesThe chromatin modifying enzymes that drive the erythroid-specific transcription program are incompletely understood. Setd8 is the sole histone methyltransferase in mammals capable of generating mono-methylated histone H4 lysine 20 (H4K20me1) and is expressed at significantly higher levels in erythroid cells than any other cell- or tissue- type, suggesting that Setd8 has an erythroid-specific function. To test this hypothesis, stable knockdown of Setd8 was established in extensively self-renewing erythroblasts (ESREs), a well-characterized, non-transformed, model of erythroid maturation. Setd8 knockdown impaired erythroid maturation, characterized by a delay in hemoglobin accumulation, larger cell area, persistent kit expression, incomplete nuclear condensation, and lower rates of enucleation than control cells. Setd8 knockdown did not alter ESRE proliferation or viability, or result in accumulation of DNA damage. Global gene expression analyses following Setd8 knockdown suggests that in erythroid cells, Setd8 functions primarily as a repressor and demonstrated high levels of Gata2 expression. Setd8 occupies critical regulatory elements in the Gata2 locus, and knockdown of Setd8 resulted in loss of H4K20me1 and gain of H4 acetylation at the Gata2 1S promoter. Taken together, these results imply that Setd8 is an important regulator of erythroid maturation that works in part through repression of Gata2. Overall design: RNA-seq was performed of Setd8 knockdown and control cells, both while the cells were proliferating, and after 6 hours of maturation.
Histone methyltransferase Setd8 represses Gata2 expression and regulates erythroid maturation.
No sample metadata fields
View SamplesThe aim of the dataset was to study on a genome-wide level the impact of Lat deficiency on gene expression in resting and activated CD4+ T cells
Quantitative proteomics analysis of signalosome dynamics in primary T cells identifies the surface receptor CD6 as a Lat adaptor-independent TCR signaling hub.
Specimen part
View SamplesDouble-stranded RNA (dsRNA) can enter different pathways in mammalian cells, including sequence-specific RNA interference, sequence-independent interferon response and editing by adenosine deaminases. To assess the potential of expressed dsRNA to induce interferon stimulated genes in somatic cells, we performed microarray analysis of HEK293 and HeLa cells transfected with a MosIR plasmid expressing an mRNA with a long inverted repeat structure in its 3UTR (MosIR) or with a parental MosIR plasmid (without inverted repeat) as a control.
dsRNA expression in the mouse elicits RNAi in oocytes and low adenosine deamination in somatic cells.
Specimen part
View SamplesRNA-seq was performed on eosinophils isolated from colons of naive C57/BL6 mice. Overall design: 2 samples of naive colonic eosinophils
Reuse of public, genome-wide, murine eosinophil expression data for hypotheses development.
Specimen part, Cell line, Subject
View SamplesMyosteatosis is the pathological accumulation of lipid that occurs in conjunction with atrophy and fibrosis following skeletal muscle injury or disease. Little is known about the mechanisms by which lipid accumulates in myosteatosis, but many studies have demonstrated the degree of lipid infiltration negatively correlates with muscle function and regeneration. Our goal was to identify biochemical pathways that lead to muscle dysfunction and lipid accumulation in injured rotator cuff muscles, a model that demonstrates severe myosteatosis. Adult rats were subjected to a massive tear to the rotator cuff musculature. After a period of either 0 (healthy control), 10, 30, or 60 days, muscles were prepared for RNA sequencing, shotgun lipidomics, metabolomics, biochemical measures, electron microscopy, and muscle fiber contractility. Following rotator cuff injury, there was a decrease in muscle fiber specific force production that was lowest at 30d. There was a dramatic time dependent increase in triacylglyceride content. Interestingly, genes related to not only triacylglyceride synthesis, but also lipid oxidation were largely downregulated over time. Using bioinformatics techniques, we identified that biochemical pathways related to mitochondrial dysfunction and reactive oxygen species were considerably increased in muscles with myosteatosis. Long chain acyl-carnitines and L-carnitine, precursors to beta-oxidation, were depleted following rotator cuff tear. Electron micrographs showed injured muscles displayed large lipid droplets within mitochondria at early time points, and an accumulation of peripheral segment mitochondria at all time points. Several markers of oxidative stress were elevated following rotator cuff tear. The results from this study suggest that the accumulation of lipid in myosteatosis is not a result of canonical lipid synthesis, but occurs due to decreased lipid oxidation in mitochondria. A failure in lipid utilization by mitochondria would ultimately cause an accumulation of lipid even in the absence of increased synthesis. Further study will identify whether this process is required for the onset of myosteatosis. Overall design: Rats were subjected to a bilateral full-thickness supraspinatus tear and suprascapular neurectomy. Samples (N=4 per group) were taken at 0 days (unoperated controls), 10 days, 30 days, and 60 days post-injury
Reduced mitochondrial lipid oxidation leads to fat accumulation in myosteatosis.
No sample metadata fields
View SamplesSmall RNAs, such as miRNAs and siRNAs, are involved in gene regulation in a variety of systems, including mouse oocytes. Dicer is a ribonuclease III enzyme essential for miRNA and siRNA biosynthesis. In an effort to uncover the function of small RNAs during oocyte growth, we specifically deleted Dicer in growing oocytes and analyzed the global pattern of gene expression in these Dicer-deficient oocytes.
MicroRNA activity is suppressed in mouse oocytes.
Sex, Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Activity-dependent regulation of inhibitory synapse development by Npas4.
No sample metadata fields
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