The Microarray study was designed to characterize the whole genome transcription profile of two subpopulations of H1 human embryonic stem cells we identified by size using flow cytometry.The heterogeneous nature of stem cells is an important issue in both research and therapeutic use in terms of directing cell lineage differentiation pathways, as well as self-renewal properties. Using flow cytometry we have identified two distinct subpopulations by size within the H1 and BGN1 human embryonic stem (hES) cell lines. Both populations express stem the cell markers Oct-4, Nanog, Tra-1-60, Tra-1-80 and SSea-4 and express very low levels of differentiation markers common to the three germ layers. To investigate if the two populations possessed different transcription profiles, we performed whole genome microarray analysis, and identified approximately 400 genes with significant differential expression (p<0.01). Cloning experiments indicate that both populations are able to repopulate each other and maintain the parental population. The large cell population responds to retinoic acid (RA) differentiation as evidenced by greater than a 50% loss of gated cell number and loss of Oct-4 expression; while the small cell population number does not change and maintains Oct-4 protein expression. The presence of these two populations could be vitally important with respect to stem cell therapy and research as they respond differently to differentiation signals, which may be important in directing stem cell differentiation for disease therapy.
Differential responses to retinoic acid and endocrine disruptor compounds of subpopulations within human embryonic stem cell lines.
Specimen part, Disease, Cell line
View SamplesThe goals of this study were to identify LIN28 downstream gene targets in breast cancer cells. We use a subclone of the MCF-7 breast cancer cell line, MCF-7M as our model system. Methods: mRNA-protein complexes (mRNP) lysates were prepared from MCF-7M cells and incubated with Protein-A Sepharose beads (Sigma-Aldrich) and either LIN28 (Abcam) or control normal rabbit serum IgG antibodies. LIN28 interacting mRNAs were identified by whole genome sequencing. Results: Using an optimized data analysis workflow, we mapped approximately 13 million sequence reads for LIN28-IP and CTL- IP (IgG), respectively to the to the human genome (build h19). Conclusions: mRNA were significantly bound by LIN28 if LIN28 RIP had 2.5 fold increase in normalized reads compared to IgG. We found that LIN28 was predominantly bound at coding exons and 3''UTRs, 38% & 45% respectively, in the 843 mRNAs within MCF-7M genome. Overall design: LIN28 mRNA enriched regions identified from LIN28/RNA complexes prepared from MCF-7M cells.
LIN28A Modulates Splicing and Gene Expression Programs in Breast Cancer Cells.
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View SamplesThis SuperSeries is composed of the SubSeries listed below.
The transcriptional programme controlled by Runx1 during early embryonic blood development.
Specimen part, Cell line
View SamplesTranscription factors have long been recognised as powerful regulators of mammalian development, yet it is largely unknown how individual key regulators operate within wider regulatory networks. Here we have used a combination of global gene expression and chromatin-immunoprecipitation approaches across four ES-cell-derived populations of increasing haematopoietic potential to define the transcriptional programme controlled by Runx1, an essential regulator of blood cell specification. Integrated analysis of these complementary genome-wide datasets allowed us to construct a global regulatory network model, which suggested that core regulatory circuits are activated sequentially during blood specification, but will ultimately collaborate to control many haematopoietically expressed genes. Using the CD41/integrin alpha 2b gene as a model, cellular and in vivo studies showed that CD41 is controlled by both early and late circuits in fully specified blood cells, but initiation of CD41 expression critically depends on a later subcircuit driven by Runx1. Taken together, this study represents the first global analysis of the transcriptional programme controlled by any key haematopoietic regulator during the process of early blood cell specification. Moreover, the concept of interplay between sequentially deployed core regulatory circuits is likely to represent a design principle widely applicable to the transcriptional control of mammalian development.
The transcriptional programme controlled by Runx1 during early embryonic blood development.
Specimen part, Cell line
View SamplesThe adenosine 2A receptor (A2AR) is expressed on regulatory T cells (Tregs), but the functional significance is currently unknown. We compared the gene expression between wild-type (WT) and A2AR knockout (KO) Tregs and between WT Tregs treated with vehicle or a selective A2AR agonist.
Autocrine adenosine signaling promotes regulatory T cell-mediated renal protection.
Specimen part
View SamplesTo explore the global mechanisms of estrogen-regulated transcription, we used chromatin immunoprecipitation coupled with DNA microarrays to determine the localization of RNA polymerase II (Pol II), estrogen receptor alpha (ERalpha), steroid receptor coactivator proteins (SRC), and acetylated histones H3/H4 (AcH) at estrogen-regulated promoters in MCF-7 cells with or without estradiol (E2) treatment. In addition, we correlated factor occupancy with gene expression and the presence of transcription factor binding elements. Using this integrative approach, we defined a set of 58 direct E2 target genes based on E2-regulated Pol II occupancy and classified their promoters based on factor binding, histone modification, and transcriptional output. Many of these direct E2 target genes exhibit interesting modes of regulation and biological activities, some of which may be relevant to the onset and proliferation of breast cancers. Our studies indicate that about one-third of these direct E2 target genes contain promoter-proximal ERalpha-binding sites, which is considerably more than previous estimates. Some of these genes represent possible novel targets for regulation through the ERalpha/AP-1 tethering pathway. Our studies have also revealed several previously uncharacterized global features of E2-regulated gene expression, including strong positive correlations between Pol II occupancy and AcH levels, as well as between the E2-dependent recruitment of ERalpha and SRC at the promoters of E2-stimulated genes. Furthermore, our studies have revealed new mechanistic insights into E2-regulated gene expression, including the absence of SRC binding at E2-repressed genes and the presence of constitutively bound, promoter-proximally paused Pol IIs at some E2-regulated promoters. These mechanistic insights are likely to be relevant for understanding gene regulation by a wide variety of nuclear receptors.
Genomic analyses of transcription factor binding, histone acetylation, and gene expression reveal mechanistically distinct classes of estrogen-regulated promoters.
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View SamplesThe loss of REST in uterine fibroids promotes aberrant gene expression and enables mTOR pathway activation
Loss of the repressor REST in uterine fibroids promotes aberrant G protein-coupled receptor 10 expression and activates mammalian target of rapamycin pathway.
Specimen part, Treatment
View SamplesUnderstanding the molecular underpinnings of cancer is of critical importance to developing targeted intervention strategies. Identification of such targets, however, is notoriously difficult and unpredictable. Malignant cell transformation requires the cooperation of a few oncogenic mutations that cause substantial reorganization of many cell features and induce complex changes in gene expression patterns. Genes critical to this multi-faceted cellular phenotype thus only have been identified following signaling pathway analysis or on an ad hoc basis. Our observations that cell transformation by cooperating oncogenic lesions depends on synergistic modulation of downstream signaling circuitry suggest that malignant transformation is a highly cooperative process, involving synergy at multiple levels of regulation, including gene expression. Here we show that a large proportion of genes controlled synergistically by loss-of-function p53 and Ras activation are critical to the malignant state. Remarkably, 14 among 24 such 'cooperation response genes' (CRGs) were found to contribute to tumor formation in gene perturbation experiments. In contrast, only one in 14 perturbations of genes responding in a non-synergistic manner had a similar effect. Synergistic control of gene expression by oncogenic mutations thus emerges as an underlying key to malignancy and provides an attractive rationale for identifying intervention targets in gene networks downstream of oncogenic gain and loss-of-function mutations.
Synergistic response to oncogenic mutations defines gene class critical to cancer phenotype.
No sample metadata fields
View SamplesThe mammalian circadian clock system is made up of individual cell and tissue clocks that function as a coherent network, however it remains unclear which rhythmic functions of the liver clock are autonomous or rely on clocks in other tissues. Here, using mice which only have a functioning liver clock, we investigate the autonomous vs non-autonomous reatures of the liver clock and diurnal rhythmicity in the liver Overall design: 8-12 week-old, female WT, KO and Liver-RE BMAL1-stop-FL mice (see referenced paper for details) were fed ad libitum normal chow under 12hr light/ 12hr dark schedule. Livers were harvested every 4 hours over the circadian cycle at ZT0, 4, 8, 12, 16, 20 (n=3 per time point per group). Total RNA was extracted and used for RNA-seq.
Defining the Independence of the Liver Circadian Clock.
Specimen part, Subject
View SamplesThe Ets transcription factor, ERG, plays a central role in definitive hematopoiesis and its overexpression in acute myeloid leukemia is associated with a stem cell signature and bad prognosis. However, little is known about the underlying mechanism by which ERG causes leukemia. Therefore we sought to identify ERG targets that participate in development of leukemia by integration of expression arrays and Chromatin immunoprecipitation.
Genome-scale expression and transcription factor binding profiles reveal therapeutic targets in transgenic ERG myeloid leukemia.
No sample metadata fields
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