This SuperSeries is composed of the SubSeries listed below.
A tissue-specific landscape of sense/antisense transcription in the mouse intestine.
Specimen part
View SamplesGenome wide expression profiling to determine the overlap of Affymetrix-signals with SOLID sequencing
A tissue-specific landscape of sense/antisense transcription in the mouse intestine.
Specimen part
View SamplesMET expression is elevated in a majority of human skin cancers but its contributions to pathogenesis have not been evaluated. In a mouse model of constitutive overexpression of HGF (MT-HGF), the incidence of squamous cell skin tumors induced by initiation with 7,12-dimethylbenz(a)anthracene (DMBA) followed by exposure to 12-O-tetradecanoyl-phorbol-13-acetate (TPA) is increased fivefold over control groups. Half of these tumors carry Hras1 or Kras mutations. Without DMBA initiation, tumors also erupt on MT-HGF mouse skin but only when TPA promotion is enhanced by crossing these mice with mice overexpressing cutaneous PKC. None of these tumors have Ras mutations. In culture, MT-HGF keratinocytes share identical MET mediated phenotypic and biochemical features with wildtype keratinocytes transformed by oncogenic RAS. In both cell types, these common features of initiated keratinocytes arise from autocrine activation of EGFR through elevated expression and release of EGFR ligands. Inhibition of EGFR ablates the initiated signature of MT-HGF keratinocytes in vitro and causes regression of MT-HGF induced tumors in vivo. Global gene expression data indicate that MT-HGF and RAS transformed keratinocytes share largely an identical profile of over 5000 mRNAs. Gene ontology analysis reveals the most affected concordant signature is enriched for functions relevant to tissue development and response to wounding, accompanied by cytokine and growth factor activity, and peptidase and endopeptidase activity previously not linked to initiated keratinocytes. Furthermore, gene co-expression analysis in skin cancer patients revealed a core RAS/MET co-expression network considerably activated in pre cancerous and cancerous lesions. Thus MET activation though EGFR contributes to human cutaneous cancers, and inhibitors could be efficacious in advanced lesions such as those seen in transplant recipient patients.
MET signaling in keratinocytes activates EGFR and initiates squamous carcinogenesis.
Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
A model system for assessing and comparing the ability of exon microarray and tag sequencing to detect genes specific for malignant B-cells.
Cell line
View SamplesThe purpose of this study was to develop a quantification method that can be used to assess the ability of tag-seq to detect malignant B-cell transcripts. The data support that tumour cell concentration is an important variable with fundamental impact on gene expression pattern. Overall design: We analysed eight serial dilutions of the malignant B-cell line, OCI-Ly8, into the embryonic kidney cell line, HEK293, by tag-sequencing. No technical replicates were performed.
A model system for assessing and comparing the ability of exon microarray and tag sequencing to detect genes specific for malignant B-cells.
Cell line, Subject
View SamplesThe purpose of this study was to develop a quantification method that can be used to assess the ability of exon microarray to detect malignant B-cell transcripts.
A model system for assessing and comparing the ability of exon microarray and tag sequencing to detect genes specific for malignant B-cells.
Cell line
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 SamplesImpaired 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 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 Samples