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SRP047000
Drosophila melanogaster
12 Downloadable Samples
Illumina HiSeq 2000
Description
PcG protein complex PRC2 is a methyltransferase specific for histone H3 lysine27, and H3K27me3 is essential for stable transcription silencing. Less well known but quantitatively much more important is the genome-wide role of PRC2 that dimethylates ~70% of total H3K27. Here we show that H3K27me2 occurs in inverse proportion to transcriptional activity in genes and intergenic regions and its loss results in global transcriptional derepression proportionally greatest in previously silent or weakly transcribed regions. H3K27me2 levels are controlled by opposing roaming activities of PRC2 and the H3K27 demethylase dUTX. Unexpectedly, we find an equally pervasive distribution of histone H2A ubiquitylated at lysine 118 (H2AK118ub), attributed to the RING1 subunit of PRC1-type complexes. Overall design: Examination of global changes in transcription genome-wide when E(z) is inactivated by monitoring total RNA from E(z) temperature-sensitive cells at 25°C and 31°C in duplicate
Publication Title
Genome-wide activities of Polycomb complexes control pervasive transcription.
Sample Metadata Fields
Cell line, Subject
View Samples- Mus musculus
- 2 Downloadable Samples
Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
Transgenic mice were generated that expressed the inhibitor of apoptosis and mitotic regulator survivin in pancreatic islet beta cells. Control non-transgenic or transgenic islets were then used in a model of islet transplantation in diabetic recipient mice and tested for their ability to correct hyperglycemia and allow long-term engraftment of tranplanted islets in vivo. Control or transgenic islets were analyzed by chip microarray for potential transcriptional changes associated with transgenic expression of survivin, in vivo.
Publication Title
Genome-wide analysis of Polycomb targets in Drosophila melanogaster.
Sample Metadata Fields
Sex, Age, Specimen part
View Samples- Drosophila melanogaster
- 12 Downloadable Samples
- Affymetrix Drosophila Genome 2.0 Array (drosophila2)
Description
Effects of Nipped-B and Rad21 sister chromatid cohesin proteins on gene expression data in ML-DmBG3 cells derived from Drosophila melanogaster larval central nervous system
Publication Title
Regulation of the Drosophila Enhancer of split and invected-engrailed gene complexes by sister chromatid cohesion proteins.
Sample Metadata Fields
Time
View Samples- Drosophila melanogaster
- 4 Downloadable Samples
- Illumina HiSeq 2000
Description
mRNA expression levels were determined by NGS for wildtype larvae as well as for larvae lacking HP1a [Su(var)205^04/Su(var)205^05 transheterozygotes]. Overall design: RNA samples from wildtype (OR) and HP1a mutant third instar larvae were examined, using duplicate biological samples and Illumina NGS.
Publication Title
Enrichment of HP1a on Drosophila chromosome 4 genes creates an alternate chromatin structure critical for regulation in this heterochromatic domain.
Sample Metadata Fields
Subject
View Samples- Drosophila melanogaster
- 8 Downloadable Samples
- Affymetrix Drosophila Genome 2.0 Array (drosophila2)
Description
This SuperSeries is composed of the SubSeries listed below.
Publication Title
Sequence-specific targeting of dosage compensation in Drosophila favors an active chromatin context.
Sample Metadata Fields
Cell line
View Samples- Drosophila melanogaster
- 8 Downloadable Samples
- Affymetrix Drosophila Genome 2.0 Array (drosophila2)
Description
The Drosophila MSL complex mediates dosage compensation by increasing transcription of the single X chromosome in males approximately two-fold. This is accomplished through recognition of the X chromosome and subsequent acetylation of histone H4K16 on X-linked genes. Initial binding to the X is thought to occur at a subset of sites. However, the consensus sequence motif of entry sites (MSL recognition element or MRE) is only slightly enriched on the X (~2 fold), and only a fraction of them is utilized by the MSL complex. Here we ask whether chromatin context could distinguish between utilized and non-utilized copies of the motif, by comparing their relative enrichment for histone modifications and chromosomal proteins mapped in the NHGRI modENCODE project. Through a comparative analysis of the chromatin features in male S2 cells, which contain MSL complex, and female Kc cells, which lack the complex, we find that the presence of active chromatin modifications, together with an elevated local GC content in surrounding sequence, has strong predictive value for functional MSL entry sites, independent of MSL binding. We tested these sites for function in Kc cells by RNAi knockdown of Sxl, resulting in induction of MSL complex. We show that ectopic MSL expression in Kc cells leads to H4K16 acetylation around these sites, and a relative increase in X chromosome transcription. Collectively, our results support a model in which a pre-existing active chromatin environment, coincident with H3K36me3, contributes to MSL entry site selection. The consequences of MSL targeting of the male X chromosome include increase in nucleosome lability, enrichment for H4K16 acetylation and JIL-1 kinase, and depletion of linker histone H1 on active X-linked genes. Our finding serves as a model to understand how chromatin and local sequence features are involved in the selection of functional protein binding sites in the genome.
Publication Title
Sequence-specific targeting of dosage compensation in Drosophila favors an active chromatin context.
Sample Metadata Fields
Cell line
View Samples- Drosophila melanogaster
- 3 Downloadable Samples
- Illumina Genome Analyzer II
Description
MSL (Male-specific lethal) complex increases transcription on the single X chromosome of Drosophila males in order to equalize expression of X-linked genes between males (XY) and females (XX). The increase in transcript levels correlates with MSL- dependent acetylation of histone H4 at K16 within the bodies of active genes, but identification of the transcriptional step affected has not been possible. In this study, we use global run-on sequencing (GRO-seq) to examine the specific effect of MSL complex on RNA Polymerase II (RNAP II) on a genome-wide level. Results indicate that MSL complex enhances transcription by facilitating the progression of RNAP II across the bodies of active X-linked genes. Improving transcriptional output downstream of typical gene-specific control may explain how dosage compensation can be imposed on the diverse set of genes along an entire chromosome. Overall design: Global Run-On Sequencing (GRO-Seq) reads, i.e., RNA-Seq of nascent RNA transcripts, from D. Melanogaster SL2 cells. Two biological replicates were analyzed.
Publication Title
Comprehensive analysis of the chromatin landscape in Drosophila melanogaster.
Sample Metadata Fields
Subject
View Samples- Mus musculus
- 12 Downloadable Samples
- Affymetrix Mouse Gene 1.0 ST Array (mogene10st)
Description
Dnmt3a catalyzes DNA methylation of gDNA, which contributes to the transriptional regulations of genes and genomic stability.
Publication Title
Methylation-independent repression of Dnmt3b contributes to oncogenic activity of Dnmt3a in mouse MYC-induced T-cell lymphomagenesis.
Sample Metadata Fields
Age, Specimen part
View Samples- Mus musculus
- 24 Downloadable Samples
- Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
Gut microbes elicit specific changes in gene expression in the colon of mice. We colonized germ-free mice with microbial communities from the guts of humans, zebrafish and termites, human skin and tongue, soil and estuarine microbial mats.
Publication Title
Bacteria from diverse habitats colonize and compete in the mouse gut.
Sample Metadata Fields
Sex, Specimen part
View Samples- Homo sapiens
- 74 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
Understanding the structure and interplay of cellular signalling pathways is one of the great challenges in molecular biology. Boolean Networks can infer signalling networks from observations of protein activation. In situations where it is difficult to assess protein activation directly, Nested Effect Models are an alternative. They derive the network structure indirectly from downstream effects of pathway perturbations. To date, Nested Effect Models cannot resolve signalling details like the formation of signalling complexes or the activation of proteins by multiple alternative input signals. Here we introduce Boolean Nested Effect Models (B-NEM). B-NEMs combine the use of downstream effects with the higher resolution of signalling pathway structures in Boolean Networks. We show that B-NEMs accurately reconstruct signal flows in simulated data. Using B-NEM we then resolve BCR signalling via PI3K and TAK1 kinases in BL2 lymphoma cell lines.
Publication Title
Analyzing synergistic and non-synergistic interactions in signalling pathways using Boolean Nested Effect Models.
Sample Metadata Fields
Specimen part, Cell line, Treatment
View Samples