Impaired DNA replication is a hallmark of cancer and a cause of genomic instability. We report that, in addition to causing genetic change, impaired DNA replication during embryonic development can have major epigenetic consequences for a genome. In a genome-wide screen, we identified impaired DNA replication as causing increased expression from a repressed transgene in Caenorhabditis elegans. The acquired expression state behaved as an “epiallele,” being inherited for multiple generations before fully resetting. Derepression was not restricted to the transgene but was caused by a global reduction in heterochromatin-associated histone modifications due to the impaired retention of modified histones on DNA during replication in the early embryo. Impaired DNA replication during development can therefore globally derepress chromatin, creating new intergenerationally inherited epigenetic expression states. Overall design: 3 replicates of div-1 mutant worms and N2 wild type worms
Impaired DNA replication derepresses chromatin and generates a transgenerationally inherited epigenetic memory.
Specimen part, Subject
View SamplesPioneer transcription factors are able to recognise and bind their motif sequences in inaccessible or closed chromatin, and their ability to achieve this is required to establish new regulatory elements and transcriptional networks during development and cellular reprogramming. An essential feature of this pioneering activity is the transition from inaccessible chromatin to a nucleosome-depleted and accessible chromatin state typical of normal regulatory elements, and this is believed to facilitate further transcription factor binding events. However, the mechanisms by which many pioneer transcription factors achieve this remarkable feat remain elusive. Here we reveal that the pluripotency-associated pioneer factor OCT4 binds inaccessible chromatin to shape the chromatin accessibility, transcription factor co-binding and regulatory potential of thousands of distal regulatory elements in mouse embryonic stem cells, demonstrating that its pioneering activity is a feature of normal pluripotency, and not just reprogramming. The accessible chromatin formed at OCT4 binding sites relies on the chromatin remodelling factor BRG1, which is recruited to these sites by OCT4. The occupancy of BRG1 is then required to support OCT4/SOX2 co-binding and normal expression of the pluripotency-associated transcriptome, and this reliance on BRG1 reflects OCT4 binding dynamics during cellular reprograming and early mouse development. Together these observations reveal a distinct requirement for the chromatin remodelling factor BRG1 in shaping the pioneering activity of OCT4 and regulating the pluripotency network in embryonic stem cells. Overall design: ZHBTC4 and Brg1fl/fl mouse embryonic stem cells were used to ablate OCT4 and BRG1 expression respectively, followed by ATAC-seq, ChIP-seq or RNA-seq to examine their contribution towards chromatin accessibility, transcription factor occupancy, and gene expression.
The pioneer factor OCT4 requires the chromatin remodeller BRG1 to support gene regulatory element function in mouse embryonic stem cells.
Cell line, Treatment, Subject
View SamplesT lymphocytes can be generated from T-cell-derived induced pluripotent stem cells (T-iPS). We used microarrays to better elucidate their phenotype and compare their gene expression profile to that of known lymhoid subsets from peripheral blood.
Generation of tumor-targeted human T lymphocytes from induced pluripotent stem cells for cancer therapy.
Specimen part
View SamplesEmbryonic mouse brain development involves a sequential differentiation of multipotent progenitor cells into neurons and glia. Using microarrays and large 2-D electrophoresis, we investigated the transcriptome and proteome of mouse brains at embryonic days 9.5, 11.5 and 13.5. During this developmental period, neural progenitor cells shift from proliferation to neuronal differentiation. As expected, we detected numerous expression changes between the time points investigated but interestingly, the rate of alteration was about 10% to 13% of all proteins and mRNAs during every two days of development. Furthermore, up- and downregulation was balanced. This was confirmed for two additional stages of development, embryonic day 16 and 18. We hypothesize that during embryonic development, the rate of protein expression alteration is rather constant due to a limitation of cellular resources such as energy, space and free water. The similar complexity found at the transcriptome and proteome level at all stages suggests, that changes in relative concentration of gene products rather than an increased number of gene products dominate throughout cellular differentiation. We found that metabolism and cell cycle related gene products were downregulated in expression when precursor cells switched from proliferation to neuronal differentiation (day 9.5 to 11.5), whereas neuron specific gene products were upregulated. A detailed analysis revealed their implication in differentiation related processes such as rearrangement of the actin cytoskeleton as well as Notch and Wnt signaling pathways.
Transcriptome and proteome analysis of early embryonic mouse brain development.
No sample metadata fields
View SamplesHepatocellular carcinoma (HCC) accounts for the majority of malignant liver tumors and results in many deaths each year, emphasizing the need for new therapies. The protein-protein interaction between menin and histone methyltransferase Mixed Lineage Leukemia 1 (MLL1) plays an important role in the development of HCC, implying that pharmacologic inhibition of this interaction could lead to new therapeutic strategy for the HCC patients. Therefore, we performed RNA sequencing experiment to determine the transcriptome change in the HepG2 cells upon treatment of MI-503, a small molecule inhibitor of the menin-MLL1 interaction with optimized drug-like properties Overall design: HepG2 cells were plated in the 12-well plates at the initial concentration of 0.4x106 cells/ml and treated with 3 µM MI-503 or DMSO (0.25%) in triplicates. After 3 days of treatment viable cell number was adjusted to the original concentration in the DMSO treated samples and the same dilution factor was used to adjust cell number in the MI-503 treated cells. Media was changed and compound or DMSO was re-supplied at that time. Cells were harvested after 3 more days of incubation.
Pharmacologic Inhibition of the Menin-MLL Interaction Leads to Transcriptional Repression of <i>PEG10</i> and Blocks Hepatocellular Carcinoma.
Treatment, Subject
View SamplesThe roles of histone demethylase RBP2 in gene expression were assessed using gene expression profiling experiments with wild type and RBP2-/- primary MEFs. Several cytokine genes including SDF1 and Kit ligand were upregulated upon inactivation of RBP2.
The retinoblastoma binding protein RBP2 is an H3K4 demethylase.
No sample metadata fields
View SamplesEstablishment of a transcriptomic profile of human cells treated with kaemferol, daidzein, kaemferol/genistein, or daidzein/genistein with particular emphasis on signature of genes coding for enzymes involved in glycosaminoglycan synthesis stands for the present study. The hypothesis tested was that kaemferol, daidzein, kaemferol/genistein, and daidzein/genistein influence expression of some genes, among which are those coding for enzymes required for the synthesis of different GAGs being pathologically accumulated in mucopolysaccharidoses. Results provide important information concerning the extent of action of kaemferol, daidzein, kaemferol/genistein, and daidzein/genistein at the molecular level in terms of modulation of gene expression.
Modulation of expression of genes involved in glycosaminoglycan metabolism and lysosome biogenesis by flavonoids.
Specimen part, Cell line, Treatment
View SamplesIn order to identify the effects of the induction of the gene of interest on the mouse ES transcriptome, we performed Affymetrix Gene-Chip hybridization experiments for the different inducible cell lines
Reverse engineering a mouse embryonic stem cell-specific transcriptional network reveals a new modulator of neuronal differentiation.
Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
A tissue-specific landscape of sense/antisense transcription in the mouse intestine.
Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Reverse engineering a mouse embryonic stem cell-specific transcriptional network reveals a new modulator of neuronal differentiation.
Cell line
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