A conserved molecular pathway has emerged controlling endoderm formation in Xenopus zebrafish and mice. Key genes in this pathway include Nodal ligands and transcription factors of the Mix-like paired homeodomain class, Gata4-6 zinc finger factors and Sox17 HMG domain proteins. While a linear epistatic pathway has been proposed, the precise hierarchical relationships between these factors and their downstream targets are largely unresolved. Here we used a combination of microarray analysis and loss-of-function experiments to examine the global regulatory network controlling Xenopus endoderm formation. We identified over 300 transcripts enriched in the gastrula endoderm, including most of the known endoderm regulators as well as over a hundred uncharacterized genes. Surprisingly only 10% of the endoderm transcriptome is regulated as predicted by the current linear model. We find that Nodals, Mixer and Sox17 have both shared and distinct sets of downstream targets and that a number of unexpected autoregulatory loops exist between Sox17 and Gata4-6, Sox17 and Bix1, 2, 4 and between Sox17 and Xnr4. We find that Mixer does not function primarily via Sox17 as previously proposed. This data provides a new insight into the complexity of endoderm formation and will serve as valuable resource for establishing a complete endoderm gene regulatory network.
Global analysis of the transcriptional network controlling Xenopus endoderm formation.
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View SamplesSecretion of insulin by pancreatic cells in response to glucose is central for glucose homeostasis, and dysregulation of this process is a hallmark of the early stages of diabetes. We utilized a tetracycline-inducible approach to investigate the immediate impact of a pulse of Sox17 expression on the insulin secretory pathway. Sox17 gain-of-function animals (Sox17-GOF) were generated using an Ins2-rtTA mouse line and a line in which Sox17 expression is regulated by the tetracycline transactivator (tetO-Sox17). Administering doxycycline to 16-week old mice resulted in Sox17 overexpression in mature cells in the islets.
Sox17 regulates insulin secretion in the normal and pathologic mouse β cell.
Age, Specimen part
View SamplesPurpose: Next-generation sequencing (NGS) has revolutionized systems-based analysis of cellular pathways. The goals of this study are to compare GBM transcriptome profiling (RNA-seq) after shRNA based knockdown of PRKAB1 and to compare gene expression by optimal high-throughput data analysis Overall design: Methods: Total RNA profiles of two GBM cells (scramble and PRKAB1 sh RNA treated) were generated by deep sequencing, in triplicate, using Illumina Hiseq 2000. The sequence reads that passed quality filters were analyzed at the transcript isoform level with two methods: Burrows–Wheeler Aligner (BWA) followed by ANOVA (ANOVA) and TopHat followed by Cufflinks. qRT–PCR validation was performed using SYBR Green assays
AMP kinase promotes glioblastoma bioenergetics and tumour growth.
Specimen part, Race, Subject
View SamplesThis SuperSeries is composed of the SubSeries listed below.
The synthetic glucocorticoids prednisolone and dexamethasone regulate the same genes in acute lymphoblastic leukemia cells.
Specimen part, Cell line, Treatment
View SamplesBackground: Glucocorticoids (GCs) cause apoptosis in malignant cells of lymphoid lineage by transcriptionally regulating a plethora of genes. As a result, GCs are included in almost all treatment protocols for lymphoid malignancies, particularly childhood acute lymphoblastic leukemia (chALL). The most commonly used synthetic GCs in the clinical setting are prednisolone and dexamethasone. While the latter has a higher activity and more effectively reduces the tumor load in patients, it is also accompanied by more serious adverse effects than the former. Whether this difference might be explained by regulation of different genes by the two GCs has never been addressed.
The synthetic glucocorticoids prednisolone and dexamethasone regulate the same genes in acute lymphoblastic leukemia cells.
Specimen part, Cell line
View SamplesBackground: Glucocorticoids (GCs) cause apoptosis in malignant cells of lymphoid lineage by transcriptionally regulating a plethora of genes. As a result, GCs are included in almost all treatment protocols for lymphoid malignancies, particularly childhood acute lymphoblastic leukemia (chALL). The most commonly used synthetic GCs in the clinical setting are prednisolone and dexamethasone. While the latter has a higher activity and more effectively reduces the tumor load in patients, it is also accompanied by more serious adverse effects than the former. Whether this difference might be explained by regulation of different genes by the two GCs has never been addressed.
The synthetic glucocorticoids prednisolone and dexamethasone regulate the same genes in acute lymphoblastic leukemia cells.
Specimen part, Cell line, Treatment
View SamplesWe use single-cell RNA sequencing (scRNA-seq) to explore the transcriptional changes associated with estrogen-induced dysplasia in mouse ovarian surface epithelial cells Overall design: scRNA-seq of control and estrogen-treated (100nM) mOSE cultured for 15 days. scRNA-seq was performed using the Fluidigm HT 3' RNA-seq protocol on the Fluidigm C1
Single-cell RNA-sequencing reveals transcriptional dynamics of estrogen-induced dysplasia in the ovarian surface epithelium.
Specimen part, Treatment, Subject
View SamplesBackground: ETV6/RUNX1 (E/R) (also known as TEL/AML1) is the most frequent gene fusion in childhood acute lymphoblastic leukemia (ALL) and also most likely the crucial factor for disease initiation, whereas its role in leukemia propagation and maintenance remains largely elusive. To address this issue we performed a shRNA-mediated knock-down (KD) of the E/R fusion gene and investigated the ensuing consequences on genome-wide gene expression patterns and deducible regulatory functions in two E/R-positive leukemic cell lines. Findings: Microarray analyses identified 777 genes whose expression was substantially altered. Although approximately equal proportions were either up- (KD-UP) or down-regulated (KD-DOWN), the effects on biological processes and pathways differed considerably. The E/R KD-DOWN set was significantly enriched for genes included in the cell activation, immune response, apoptosis, signal transduction and development and differentiation categories, whereas in the E/R KD-UP set only the PI3K/AKT/mTOR signaling and hematopoietic stem cells categories became evident. Comparable expression signatures obtained from primary E/R-positive ALL samples underline the relevance of these pathways and molecular functions. We also validated six differentially expressed genes representing the categories stem cell properties, B-cell differentiation, immune response, cell adhesion and DNA damage with RT-qPCR. Conclusion: The results of our analyses provide the first preliminary evidence that the continuous expression of the E/R fusion gene interferes with regular B-cell development by repressing key functions that are necessary under physiological circumstances. E/R may thus constitute also the essential driving force for the propagation and maintenance of the leukemic process irrespective of potential consequences of associated secondary changes. Finally, these findings may also provide a valuable source of potentially attractive therapeutic targets.
The leukemia-specific fusion gene ETV6/RUNX1 perturbs distinct key biological functions primarily by gene repression.
Cell line, Treatment
View SamplesGlucocorticoids (GCs) are a central component in treating childhood acute lymphoblastic leukemia (chALL). They mainly act via regulating gene transcription. However, control of mRNA translation by GC has never been assessed systematically. In our research, T- and precursor B-ALL cells were cultured with and without GC for 6 hours and subjected to translational profiling, a technique combining sucrose gradient fractionation and microarray analysis of mRNA in different fractions. Analysis of GC regulation in different pools revealed no significant differences in regulation of mRNA translation by GC, suggesting no evidence for translational regulation by GC.
Translational profiling in childhood acute lymphoblastic leukemia: no evidence for glucocorticoid regulation of mRNA translation.
Cell line, Treatment
View SamplesEWS-FLI1 is a chimeric ETS transcription factor that is, due to a chromosomal rearrangement, specifically expressed in Ewings sarcoma family tumors (ESFT) and is thought to be the initiating event in the development of the disease. Previous genomic profiling experiments have identified a number of EWS-FLI1 regulated genes and genes that discriminate ESFT from other sarcomas, but so far a comprehensive analysis of EWS-FLI1 dependent molecular functions characterizing this aggressive cancer is lacking. In this study a molecular function map of ESFT was constructed based on an integrative analysis of gene expression profiling experiments on a uniform microarray platform following EWS-FLI1 knockdown in a panel of five ESFT cell lines, and on gene expression data from the same platform of 59 primary ESFT tumors. Based on the assumption that EWS-FLI1 is the driving transcriptional force in ESFT pathogenesis, we predicted an inverse correlation of gene expression for EWS-FLI1 regulated genes between the putative tissue of origin and the cell lines under EWS-FLI1 knockdown conditions. Consistent with recent reports, mesenchymal progenitor cells (MPC) were found to fit this hypothesis best and were therefore used as the reference tissue for the construction of the molecular function map in ESFT.
A molecular function map of Ewing's sarcoma.
No sample metadata fields
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