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GSE6141
Drosophila melanogaster
9 Downloadable Samples
Affymetrix Drosophila Genome 2.0 Array (drosophila2)
Description
To determine the physiological targets of the NELF complex, and provide insight into the mechanism of NELF activity in vivo.
Publication Title
NELF-mediated stalling of Pol II can enhance gene expression by blocking promoter-proximal nucleosome assembly.
Sample Metadata Fields
No sample metadata fields
View Samples- Homo sapiens
- 11 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
In this study we examined the influence of seminal plasma on gene expression in human Ect1 ectocervical epithelial cells, and the extent to which recombinant TGF3 elicits comparable changes. Ect1 cells were incubated with recombinant human TGF3 (5 ng/ml), 10% pooled human seminal plasma (v/v), or medium alone for 10h. RNA was reverse transcribed into cDNA and hybridized to Affymetrix GeneChip Human Genome U133 plus 2.0 microarrays (Affymetrix, Santa Clara, CA). Exposure of Ect1 cells to seminal plasma resulted in differential expression of a total of 3955 probe sets, identified using high stringency criteria with MAS 5.0 analysis. These corresponded to 1338 genes up-regulated and 1343 genes down-regulated by seminal plasma. TGF3 treatment of Ect1 cells resulted in differential expression of 884 probe sets, corresponding to 346 up-regulated genes and 229 down-regulated genes. The genes differentially regulated by seminal plasma included several genes associated with cytokinecytokine receptor interaction, TGF signalling, JAK/STAT signalling or VEGF signalling pathways, as specified by the KEGG database. Of 47 genes in these families, 17 (36.1%) were similarly regulated by both seminal plasma and TGF3. These data, together with additional experiments showing all three TGF isoforms can regulate inflammatory cytokine expression in Ect1 cells, identify TGF isoforms as key agents in seminal plasma that signal induction of pro-inflammatory cytokine synthesis in cervical cells.
Publication Title
TGF-β mediates proinflammatory seminal fluid signaling in human cervical epithelial cells.
Sample Metadata Fields
Cell line, Treatment
View Samples- Drosophila melanogaster
- 6 Downloadable Samples
- Affymetrix Drosophila Genome 2.0 Array (drosophila2)
Description
This SuperSeries is composed of the SubSeries listed below.
Publication Title
Pausing of RNA polymerase II disrupts DNA-specified nucleosome organization to enable precise gene regulation.
Sample Metadata Fields
Specimen part
View Samples- Drosophila melanogaster
- 13 Downloadable Samples
Illumina Genome Analyzer IIx, Illumina Genome Analyzer
Description
Control of RNA transcription is critical for the development and homeostasis of all organisms, and can occur at multiple steps of the transcription cycle, including RNA polymerase II (Pol II) recruitment, initiation, promoter-proximal pausing, and elongation. That Pol II accumulates on many promoters in metazoans implies that steps other than Pol II recruitment are rate-limiting and regulated 1-6. By integrating genome-wide Pol II chromatin immunoprecipition (ChIP) and Global Run-On (GRO) genomic data sets from Drosophila cells, we examined critical features of Pol II near promoters. The accumulation of promoter-proximal polymerase is widespread, occurring on 70% of active genes; and unlike elongating Pol II within the body of genes, promoter Pol II are held paused by factors like NELF, unable to transcribe unless nuclei are treated with strong detergent. Notably, we find that the vast majority of promoter-proximal Pol II detected by ChIP are paused, thereby identifying the biochemical nature of this rate-limiting step in transcription. Finally, we demonstrate that Drosophila promoters do not have the upstream divergent Pol II that is seen so broadly and prominently on mammalian promoters. We postulate this is a consequence of Drosophila's extensive use of directional core promoter sequence elements, which contrasts with mammals' lack of directional elements and prevalence of CpG island core promoters. In support of this idea, we show that the fraction of mammalian promoters containing a TATA box core element is dramatically depleted of upstream divergent transcription. Overall design: Comparison of multiple GRO-seq data sets
Publication Title
Defining the status of RNA polymerase at promoters.
Sample Metadata Fields
Cell line, Treatment, Subject
View Samples- Drosophila melanogaster
- 6 Downloadable Samples
- Affymetrix Drosophila Genome 2.0 Array (drosophila2)
Description
Metazoan transcription is controlled through either coordinated recruitment of transcription machinery to the gene promoter, or subsequently, through regulated pausing of RNA polymerase II (Pol II) in early elongation. We report that a key difference between genes that use these distinct regulatory strategies lies in the chromatin architecture specified by their DNA sequences. Pol II pausing is prominent at highly-regulated genes whose sequences inherently disfavor nucleosome formation within the gene, but favor nucleosomal occlusion of the promoter. Pausing of polymerase maintains these genes in an active state by inhibiting the formation of repressive promoter chromatin. In contrast, promoters of housekeeping genes that lack paused Pol II are deprived of nucleosomes regardless of polymerase binding, but show higher nucleosome occupancy downstream. Our results suggest that the default chromatin state of a gene instructs its regulation, and that highly-regulated promoters have evolved to encourage competition between nucleosomes and paused Pol II for promoter occupancy.
Publication Title
Pausing of RNA polymerase II disrupts DNA-specified nucleosome organization to enable precise gene regulation.
Sample Metadata Fields
Specimen part
View Samples- Drosophila melanogaster
- 6 Downloadable Samples
- Affymetrix Drosophila Genome 2.0 Array (drosophila2)
Description
Regulation of gene expression is integral to the development and survival of all organisms. Transcription begins with the assembly of a pre-initiation complex at the gene promoter, followed by initiation of RNA synthesis and the transition to productive elongation. In many cases, recruitment of RNA polymerase II (Pol II) to a promoter is necessary and sufficient for activation of gene. However, there are a few notable exceptions to this paradigm, including heat shock genes and several proto-oncogenes, whose expression is attenuated by regulated stalling of polymerase elongation within the promoter-proximal region. To determine the importance of polymerase stalling for transcription regulation, we performed a genome-wide search for Drosophila genes with promoter-proximally stalled Pol II. Our data reveal that stalling is widespread, occurring at hundreds of genes that respond to stimuli and developmental signals, indicating a role for regulation of polymerase elongation in the transcriptional responses to dynamic environmental and developmental cues.
Publication Title
RNA polymerase is poised for activation across the genome.
Sample Metadata Fields
No sample metadata fields
View Samples- Mus musculus, Homo sapiens
- 12 Downloadable Samples
- Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
This SuperSeries is composed of the SubSeries listed below.
Publication Title
Activation of the aryl hydrocarbon receptor dampens the severity of inflammatory skin conditions.
Sample Metadata Fields
Sex, Age, Specimen part, Treatment, Subject
View Samples- Homo sapiens
- 84 Downloadable Samples
- IlluminaHiSeq2000
Description
Environmental stimuli are known to contribute to psoriasis pathogenesis and that of other autoimmune diseases, but the mechanism is unknown. Here we show that the aryl hydrocarbon receptor (AhR), a transcription factor that senses environmental stimuli, modulates pathology in psoriasis. AhR-activating ligands reduced inflammation in the lesional skin of psoriasis patients, whereas AhR antagonists upregulated inflammation. Similarly, AhR signaling via the endogenous FICZ ligand reduced the inflammatory response in the imiquimod-induced model of psoriasis and AhR deficient mice exhibited a substantial exacerbation of the disease, compared to AhR sufficient controls. Non-haematopoietic cells, in particular keratinocytes, were responsible for this hyper-inflammatory response, which involved increased reactivity to IL-1beta and upregulation of AP-1 family members of transcription factors. Thus, our data suggest a critical role for AhR in the regulation of inflammatory responses and open the possibility for novel therapeutic strategies in chronic inflammatory disorders. Overall design: Total RNA obtained from skin explants taken from psoriatic patients or healthy donors cultured in the presence of AhR agonist or antagonist
Publication Title
Activation of the aryl hydrocarbon receptor dampens the severity of inflammatory skin conditions.
Sample Metadata Fields
No sample metadata fields
View Samples- Mus musculus
- 12 Downloadable Samples
- Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
Environmental stimuli are known to contribute to psoriasis pathogenesis and that of other autoimmune diseases, but the mechanism is unknown. Here we show that the aryl hydrocarbon receptor (AhR), a transcription factor that senses environmental stimuli, modulates pathology in psoriasis. AhR-activating ligands reduced inflammation in the lesional skin of psoriasis patients, whereas AhR antagonists upregulated inflammation. Similarly, AhR signaling via the endogenous FICZ ligand reduced the inflammatory response in the imiquimod-induced model of psoriasis and AhR deficient mice exhibited a substantial exacerbation of the disease, compared to AhR sufficient controls. Non-haematopoietic cells, in particular keratinocytes, were responsible for this hyper-inflammatory response, which involved increased reactivity to IL-1beta and upregulation of AP-1 family members of transcription factors. Thus, our data suggest a critical role for AhR in the regulation of inflammatory responses and open the possibility for novel therapeutic strategies in chronic inflammatory disorders.
Publication Title
Activation of the aryl hydrocarbon receptor dampens the severity of inflammatory skin conditions.
Sample Metadata Fields
Specimen part
View Samples- Mus musculus
- 82 Downloadable Samples
- Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
This SuperSeries is composed of the SubSeries listed below.
Publication Title
The role of hypoxia in 2-butoxyethanol-induced hemangiosarcoma.
Sample Metadata Fields
Specimen part, Treatment, Time
View Samples