Neuroendocrine (NE) cells use large dense core vesicles (LDCVs) to traffic, process, store and secrete neuropeptide hormones through the regulated secretory pathway. The DIMM basic helix-loop-helix transcription factor of Drosophila controls the level of regulated secretory activity in NE cells. To pursue its mechanisms, we have performed two independent genome-wide analyses of DIMM's activities: (i) in vivo chromatin immunoprecipitation (ChIP) to define genomic sites of DIMM occupancy and (ii) deep sequencing of purified DIMM neurons to characterize their transcriptional profile. By this combined approach, we showed that DIMM binds to conserved E-boxes in enhancers of 212 genes whose expression is enriched in DIMM-expressing NE cells. DIMM binds preferentially to certain E-boxes within first introns of specific gene isoforms. Statistical machine learning revealed that flanking regions of putative DIMM binding sites contribute to its DNA binding specificity. DIMM's transcriptional repertoire features at least 20 LDCV constituents. In addition, DIMM notably targets the pro-secretory transcription factor, CREB-A, but significantly, DIMM does not target any neuropeptide genes. DIMM therefore prescribes the scale of secretory activity in NE neurons, by a systematic control of the regulated secretory pathway at steps that are both proximal and distal.
Genome-wide features of neuroendocrine regulation in Drosophila by the basic helix-loop-helix transcription factor DIMMED.
Sex, Specimen part
View SamplesTo amass candidate DIMM targets in addition to Phm (Park et al., 2008a), we used genome-wide microarray profiling by over-expressing DIMM throughout the embryonic nervous system. We compared profiles from experimental (elav>dimm) and control (elav-GAL4) embryos at 22-26 hr and 28-32 hr after egg laying (AEL). The design was intended to identify transcripts consistently up-regulated shortly after the induction of DIMM; in so doing, we could circumvent the lethality that ensues in late embryonic, and/ or by early larval stages, due to pan-neuronal DIMM expression.
Molecular organization of Drosophila neuroendocrine cells by Dimmed.
Specimen part
View SamplesMice lacking the transcription factor Fezf1 exhibit defects in the structural and molecular organiztion of their olfactory system. To invetigate this at the level of gene expression, we isolated Fezf1 expressing cells by FACS from the MOE of Fezf1+/- or Fezf1-/- animals and compared their gene expression profiles.
Fezf1 and Fezf2 are required for olfactory development and sensory neuron identity.
Specimen part
View SamplesLiver fibrosis is characterized by the excessive formation and accumulation of matrix proteins as a result of wound healing in the liver. A main event during fibrogenesis is the activation of the liver resident quiescent hepatic stellate cell (qHSC). Recent studies suggest that reversion of the activated HSC (aHSC) phenotype into a quiescent-like phenotype could be a major cellular mechanism underlying fibrosis regression in the liver, thereby offering new therapeutic perspectives for the treatment of liver fibrosis. The goal of the present study is to identify experimental conditions that can revert the activated status of human HSCs and to map the molecular events associated with this phenotype reversion by gene expression profiling
In vitro reversion of activated primary human hepatic stellate cells.
Sex, Age, Specimen part, Subject
View SamplesWe are investigating hepatic transcriptional responses associated with castration and tumorigenic hepatitis induced by Helicobacter hepaticus infection in mature male A/JCr mice
Hepatocellular carcinoma associated with liver-gender disruption in male mice.
No sample metadata fields
View SamplesAdult-derived human liver stem/progenitor cells (ADHLSC) are obtained after primary culture of the liver parenchymal fraction. The cells are of fibroblastic morphology and exhibit a hepato-mesenchymal phenotype. Hepatic stellate cells (HSC) derived from the liver non-parenchymal fraction present a comparable morphology as ADHLSC. Because both ADHLSC and HSC are described as liver stem/progenitor cells, we strived to extensively compare both cell populations at different levels and to propose tools demonstrating their singularity.
Gene expression profiling and secretome analysis differentiate adult-derived human liver stem/progenitor cells and human hepatic stellate cells.
Specimen part
View SamplesThe molecular determinants of a healthy human liver cell phenotype remain largely uncharacterized. In addition, the gene expression changes associated with activation of primary human hepatic stellate cells, a key event during fibrogenesis, remain poorly characterized. Here, we provide the transriptomic profile underpinning the healthy phenotype of human hepatocytes, liver sinusoidal endothelial cells (LSECs) and quiescent hepatic stellate cells (qHSCs) as well as activated HSCs (aHSCs)
Genome-wide analysis of DNA methylation and gene expression patterns in purified, uncultured human liver cells and activated hepatic stellate cells.
Sex, Age, Specimen part, Subject
View SamplesPurpose: The purpose of this study is to identify functionally inter-connected group of miRNAs whose reduced expression promotes leukemia development in vivo. We searched for relevant target genes of these miRNAs that are upregulated in T-ALL relative to controls. Methods: In order to examine the global gene expression, we generated 9 T-ALL patients and 4 normal controls by deep sequencing using Illumina Hi-Seq sequencer. The sequence reads that passed quality filters were analyzed using Spliced Transcripts Alignment to a Reference aligner (STAR) followed by differential gene expression analysis using DESeq. Results: Using an optimized data analysis workflow, we mapped reads per sample to the human genome (build hg19) and identified transcripts in both patient and controls with STAR workflow. We applied a machine learning approach to eliminate targets with redundant miRNA-mediated control. This strategy finds a convergence on the Myb oncogene and less prominent effects on the Hpb1 transcription factor. The abundance of both genes is increased in T-ALL and each can promote T-ALL in vivo. Conclusion: Our study reveals a Myc regulated network of tumor suppressor miRNAs in T-ALL. We identified a small number of functionally validated tumor suppressor miRNAs. These miRNAs are repressed upon Myc activation and this links their expression directly to Myb a key oncogenic driver in T-ALL. Overall design: Examination of global gene expression in 9 T-ALL patients and 4 normal controls using total RNA sequencing. BaseMeanA in DESeq_results.xlsx is the control.
Characterization of a set of tumor suppressor microRNAs in T cell acute lymphoblastic leukemia.
No sample metadata fields
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Integrative genomic and transcriptomic analysis identified candidate genes implicated in the pathogenesis of hepatosplenic T-cell lymphoma.
Age, Specimen part, Disease, Treatment
View SamplesUnveiling the regulatory pathways maintaining hepatic stellate cells (HSC) in a quiescent (q) phenotype is essential to develop new therapeutic strategies to treat fibrogenic diseases. To uncover the miRNA-mRNAs regulatory interactions in qHSCs, HSCs were FACS-sorted from healthy livers and activated HSCs were generated in vitro. MiRNA Taqman array analysis showed HSCs expressed a low number of miRNA, from which 46 were down-regulated and 212 up-regulated upon activation. Computational integration of miRNA and gene expression profiles revealed that 66% of qHSCs miRNAs correlated with more than 6 altered targeted mRNAs (17,2810,7 targets/miRNA), whereas aHSC-associated miRNAs had an average of 1,49 targeted genes. Interestingly, interaction networks generated by miRNA-targeted genes in qHSCs were associated with key HSCs activation processes. Next, selected miRNAs were validated in healthy and cirrhotic human livers and miR-192 was chosen for functional analysis. Down-regulation of miR-192 in HSC was found to be an early event during fibrosis progression in mouse models of liver injury. Moreover, mimic assays for miR-192 in HSCs revealed its role in HSC activation, proliferation and migration. Together, these results uncover the importance of miRNAs in the maintenance of qHSC phenotype and form the basis for understanding the regulatory networks in HSCs.
Integrative miRNA and Gene Expression Profiling Analysis of Human Quiescent Hepatic Stellate Cells.
Specimen part
View Samples