Common ALL (cALL) is the most frequent entity of childhood ALL and carries an early pre-B cell phenotype. Expression patterns of 25 pediatric cALL samples were analyzed by use of high-density DNA microarrays HG-U133A.
MondoA is highly overexpressed in acute lymphoblastic leukemia cells and modulates their metabolism, differentiation and survival.
Specimen part
View SamplesAcute lymphoblastic leukemia (ALL) is the most common childhood cancer. To identify novel candidates for targeted treatment of childhood ALL, we performed a comprehensive transcriptome analysis yielding a set of genes specifically overexpressed in ALL. Among them we identified MondoA - a transcription factor regulating glycolysis in response to glucose availability. Here, we confirm that MondoA is highly overexpressed ALL, whereas the MondoA paralog, MondoB, is not expressed. Expression studies revealed that MondoA is not regulated by glucose availability in leukemia cells, but by the presence of lactate. An in silico MondoA promoter analysis identified two methylation-prone CpG-islands and four conserved binding sites for runt-related transcription factor 1 (RUNX1). In fact, MondoA and RUNX1 are significantly coexpressed in leukemia and experimental blockage of DNA methylation leads to a further induction of MondoA. In addition, using microarray profiling, gene-set enrichment analysis and RNA interference we provide for the first time evidence that MondoA expression not only increases glucose catabolism, but also maintains a more immature ALL phenotype, which is associated with enhanced survival and clonogenicity of leukemia cells. These data hint to an important contribution of MondoA to leukemia aggressiveness validating MondoA as an attractive candidate for targeted treatment of ALL.
MondoA is highly overexpressed in acute lymphoblastic leukemia cells and modulates their metabolism, differentiation and survival.
Specimen part, Cell line
View SamplesBiochemical fractionation of HEK293 nuclei and RNA-seq of chromatin-associated and soluble-nuclear RNA. Overall design: Nuclei from three biological replicates were isolated by detergent lysis, fractionated, then three chromatin and three soluble RNA samples were converted to cDNA using Illumina TruSeq stranded protocol, and sequenced on Illumina HiSeq2000
Nuclear Fractionation Reveals Thousands of Chromatin-Tethered Noncoding RNAs Adjacent to Active Genes.
No sample metadata fields
View SamplesWe performed single-cell RNA sequencing (RNA-seq) during the in vitro transition of mouse ESCs (mESCs) from a naïve pluripotent state into epiblast-like cells (EpiLCs), a primed pluripotent state. We derived pseudotime expression trajectories to investigate transcript dynamics of key metabolic regulators, with the aim to identify metabolic pathways that potentially impact on early embryonic cell state transitions. Overall design: Single-cell RNA-seq during the in vitro differentiation of mouse embryonic stem cells (ESCs) in 2i culture conditions (time point t=0h) into epiblast-like cells (EpiLCs) at time points t=24h and t=48h.
Metabolic regulation of pluripotency and germ cell fate through α-ketoglutarate.
Specimen part, Cell line, Subject
View SamplesThe rapid evolution of toxin resistance in animals has important consequences for the ecology of species and our economy. Pesticide resistance in insects has been a subject of intensive study, however, very little is known about how Drosophila species became resistant to natural toxins with ecological relevance, such as -amanitin that is produced in deadly poisonous mushrooms. Here we performed a microarray study to elucidate the genes, chromosomal loci, molecular functions, biological processes, and cellular components that contribute to the -amanitin resistance phenotype in Drosophila melanogaster. We suggest that toxin entry blockage through the cuticle, phase I and II detoxification, sequestration in lipid particles, and proteolytic cleavage of -amanitin contribute in concert to this quantitative trait. We speculate that the resistance to mushroom toxins in Drosophila melanogaster and perhaps in mycophagous Drosophila species has evolved as a cross-resistance to pesticides or other xenobiotic substances.
The mechanisms underlying α-amanitin resistance in Drosophila melanogaster: a microarray analysis.
Specimen part
View SamplesComparison of sense (forward probes) and antisense (reverse probes on U74 v1 gene arrays) transcripts in mouse kidney and brain.
Expression profiling of antisense transcripts on DNA arrays.
No sample metadata fields
View SamplesCommonalities and dissimilarities between the IGF1R and INSR pathways
Systems Analysis of Insulin and IGF1 Receptors Networks in Breast Cancer Cells Identifies Commonalities and Divergences in Expression Patterns.
Cell line
View SamplesIdentification of filamin-A as a target for insulin and IGF1 action.
Genome-Wide Analyses Identify Filamin-A As a Novel Downstream Target for Insulin and IGF1 Action.
Cell line, Treatment
View SamplesBackground: Eukaryotic cells express a complex layer of noncoding RNAs. An intriguing family of regulatory RNAs includes transcripts from the opposite strand of protein coding genes, so called natural antisense transcripts (NATs). Here, we test the hypothesis that antisense transcription triggers RNA interference and gives rise to endogenous short RNAs (endo-siRNAs). Methods/Results: We used cloned human embryonic kidney cells (HEK293) followed by short RNAseq to investigate the small genic RNA transcriptome. 378 genes gave rise to short RNA reads that mapped to exons of RefSeq genes. The length profile of short RNAs showed a broad peak of 20-24 nucleotides, indicative of endo-siRNAs. Collapsed reads mapped predominantly to the first and the last exon of genes (74%). RNAs reads were intersected with sequences occupied by RNAPolII or bound to Argonaute (AGO1 by crosslinking, ligation, and sequencing of hybrids, CLASH). In the first exon, 94% of the reads correlated with PolII occupancy with an average density of 130 (relative units); this decreased to 65%/20 in middle exons and 54%/12 in the last exon. CLASH reads mapping to multi-exon genes showed little distribution bias with an average of about 5 CLASH reads overlapping with 60% of the endo-siRNA reads. However, endo-siRNAs (21-25 nt) intersecting with CLASH reads were enriched at the 5''end and decreased towards the 3''end. We then investigated the 378 genes with particular focus on features indicative for short RNA production; however, found that endo-siRNA numbers did not correlate with gene structures that favor convergent transcription. In contrast, our gene set was found notably over-represented in the NATsDB sense/antisense group as compared to non-overlapping and non-bidirectional groups. Moreover, read counts showed no correlation with the steady-state levels of the related mRNAs and the pattern of endo-siRNAs proved reproducible after an induced mutagenic insult. Conclusions: Our results suggest that antisense transcripts contribute to low levels of endo-siRNAs in fully differentiated human cells. A characteristic endo-siRNA footprint is being produced at sites of RNAPolII transcription which is also related to AGO1. This endo-siRNA signature represents an intriguing finding and its reproducibility suggests that the production of endo-siRNAs is a regulated process with potential homoeostatic impact. Overall design: Size selected RNASeq of 3 human embryonic kidney cell (HEK293) samples. 1 control and 2 samples exposed to 100 µg/ml ethyl methanesulfonate for 24 hrs.
Contribution of natural antisense transcription to an endogenous siRNA signature in human cells.
No sample metadata fields
View SamplesThe loss of loricrin, a major component of the cornified envelope, results in a delay of epidermal barrier formation. Therefore, the living layers of the epidermis are aberrantly exposed to late-stage amniotic fluid, which may serve as the signal to upregulate genes that functionally compensate for the loss of loricrin. Consistent with this hypothesis, metabolomic studies revealed marked changes in amniotic fluid between E14.5 and E16.5 dpc. In addition, we discovered that the Nrf2/Keap1 pathway detects these compositional changes and directly upregulates the expression of genes involved in the compensatory response, thus ensuring postnatal survival. In support of this finding, we demonstrate that genetically blocking the Nrf2 pathway abolishes the compensatory response, and preemptively activating Nrf2 pharmacologically rescues the delay in barrier formation in utero. Our findings reveal that the functions of Nrf2 and the composition of amniotic fluid have co-evolved to ensure the formation of a functional barrier.
Amniotic fluid activates the nrf2/keap1 pathway to repair an epidermal barrier defect in utero.
Specimen part
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