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GSE18128
Saccharomyces cerevisiae
22 Downloadable Samples
Affymetrix Yeast Genome S98 Array (ygs98)
Description
Despite the scientific and applied interest in anaerobic metabolism of Saccharomyces cerevisiae, not all genes whose transcription is up-regulated under anaerobic conditions have yet been linked to known transcription factors. Experiments with a reporter construct in which the promoter of the anaerobically up-regulated TIR1 gene was fused to LacZ revealed a complete loss of anaerobic up-regulation in a snf7 mutant. Anaerobic up-regulation was restored by expression of a truncated allele of RIM101 that encodes for a constitutively active Rim101p transcription factor. Analysis of LacZ expression in several deletion mutants confirmed that the effect of Snf7p on anaerobic up-regulation of TIR1 involved Rim101p and did not require a functional multi-vesicular body sorting pathway (in which Snf7p also participates). Transcriptome analysis in anaerobic chemostat cultures revealed that 26 additional genes exhibited a Snf7p/Rim101p dependent anaerobic up-regulation. Since, in its activated form, Rim101p is generally known as a transcriptional repressor, its role in anaerobic up regulation of TIR1 and other anaerobic yeast genes must involve additional factors. Further studies with deletion mutants in NRG1, NRG2 and SMP1, which were previously shown to be regulated by Rim101p, showed that these genes were not involved in the regulation of TIR1. However, the aerobic repression mechanism of TIR1 involved the general repressor Ssn6p-Tup1p complex. The physiological relevance of Snf7p/Rim101p-mediated transcriptional up-regulation of several genes in anaerobic yeast cultures was evident from reduced growth of a snf7 under anaerobic conditions.
Publication Title
Involvement of Snf7p and Rim101p in the transcriptional regulation of TIR1 and other anaerobically upregulated genes in Saccharomyces cerevisiae.
Sample Metadata Fields
No sample metadata fields
View Samples- Homo sapiens
- 17 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
To elucidate the molecular mechanisms of tamoxifen resistance in breast cancer, we performed gene array analysis and identified 366 genes with altered expression in four unique tamoxifen resistant (TamR) cell lines vs the parental tamoxifen sensitive MCF7/S0.5 cell line. Most of these genes were funcationally linked to cell proliferation, death and control gene expression, and include FYN, PRKCA, ITPR1, DPYD, DACH1, LYN, GBP1 and PRLR. Treatment with FYN specific small interfering RNA or a SRC family kinase inhibitor reduced cell growth of TamR cell lines while exerting no significant effect on MCF7/S0.5 cells. Moreover, overexpression of FYN in parental tamoxifen-sensitive MCF7/S0.5 cells resulted in reduced sensitivity to tamoxifen, demonstrating growth and survival promoting function of FYN in MCF7 cells. FYN knockdown in TamR cells led to reduced phosphorylation of 14-3-3 and CDc 25A, suggesting that FYN, by activation of of important cell cycle-associated proteins, may overcome the anti-proliferative effects of tamoxifen. Evaluation of the subcellular localization of FYN in primary breast tumors from two cohorts of endocrine-treated ER+ breast cancer patients, one with advanced disease (N = 47) and the other with early disease (N = 76), showed that in the former, plasma membrane-associated FYN expression strongly correlated with longer progression-free survival (P<0.0002). Similarly, in early breast cancer patients, membrane-associated expression of FYN in the primary breast tumor was significantly associated with increased metastasis-free (P<0.04) and overall (P<0.004) survival independent of tumor size, grade or lymph node status. Our results indicate that FYN has an important role in tamoxifen resistance, and its subcellular localization in breast tumor cells may be an important novel biomarker of response to endocrine therapy in breast cancer.
Publication Title
Gene expression profiling identifies FYN as an important molecule in tamoxifen resistance and a predictor of early recurrence in patients treated with endocrine therapy.
Sample Metadata Fields
Specimen part, Cell line
View Samples- Mus musculus
- 25 Downloadable Samples
- Affymetrix Mouse Gene 1.0 ST Array (mogene10st)
Description
This SuperSeries is composed of the SubSeries listed below.
Publication Title
Profiling peripheral nerve macrophages reveals two macrophage subsets with distinct localization, transcriptome and response to injury.
Sample Metadata Fields
No sample metadata fields
View Samples- Mus musculus
- 25 Downloadable Samples
Affymetrix Mouse Gene 1.0 ST Array (mogene10st)
Description
We performed ontogenic, transcriptomic and spatial characterization of sciatic nerve Macs (snMacs). Using multiple fate-mapping systems, we show that snMacs do not derive from the early embryonic precursors colonizing the CNS, but originate primarily from late embryonic precursors and get replaced by bone marrow-derived Macs over time. Using single-cell profiling, we identified a tissue-specific core signature of snMacs and found two spatially-separated snMacs: Relmα + Mgl1 + snMacs in the epineurium and Relmα Mgl1 snMacs in the endoneurium. Globally, snMacs lack most core signature genes of microglia, with only the endoneurial subset expressing a restricted number of these genes. Single-cell transcriptomics revealed that in response to injury both snMacs respond differently and that the PNS, in contrast to the CNS, is permissive to prolonged engraftment of monocyte-derived Macs recruited upon injury.
Publication Title
Profiling peripheral nerve macrophages reveals two macrophage subsets with distinct localization, transcriptome and response to injury.
Sample Metadata Fields
No sample metadata fields
View Samples- Homo sapiens
- 8 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
Use existing public data, cell lines and patient tumors with a personalized medicine approach to predict effective therapies for treatment of Neurofibroma tumors.
Publication Title
Molecular-guided therapy predictions reveal drug resistance phenotypes and treatment alternatives in malignant peripheral nerve sheath tumors.
Sample Metadata Fields
Specimen part
View Samples- Drosophila melanogaster
- 24 Downloadable Samples
Illumina HiSeq 2500
Description
Eukaryotic mRNAs undergo a cycle of transcription, nuclear export, and degradation. A major challenge is to obtain a global, quantitative view of these processes. Here we measured the genome-wide nucleocytoplasmic dynamics of mRNA in Drosophila cells by metabolic labeling in combination with cellular fractionation. By mathematical modeling of these data we determined rates of transcription, export and cytoplasmic decay for >5,000 genes. We characterized these kinetic rates and investigated links with mRNA features, RNA-binding proteins (RBPs) and chromatin states. We found prominent correlations between mRNA decay rate and transcript size, while nuclear export rates are linked to the size of the 3''UTR. Transcription, export and decay rates are each associated with distinct spectra of RBPs. Specific classes of genes, such as those encoding cytoplasmic ribosomal proteins, exhibit characteristic combinations of rate constants, suggesting modular control. Overall, transcription and decay rates have a major impact on transcript abundance, while nuclear export is of minor importance. Finally, correlations between rate constants suggest global coordination between the three processes. Our approach should be generally applicable to other cell systems and provides insights into the genome-wide nucleocytoplasmic kinetics of mRNA. Overall design: 24 RNA-seq experiments comprising 2 biological replicates: pre-exsiting nuclear mRNA time 0h (samples 1&13), pre-exsiting nuclear mRNA time 0.5h (samples 2&14), pre-exsiting nuclear mRNA time 1.5h (samples 3&15) , pre-exsiting nuclear mRNA time 3h (samples 4&16), pre-exsiting nuclear mRNA time 5h (samples 5&17), pre-exsiting nuclear mRNA time 7.5h (samples 6&18), pre-exsiting cytoplasmic mRNA time 0h (samples 7&19), pre-exsiting cytoplasmic mRNA time 0.5h (samples 8&20), pre-exsiting cytoplasmic mRNA time 1.5h (samples 9&21) , pre-exsiting cytoplasmic mRNA time 3h (samples 10&22), pre-exsiting cytoplasmic mRNA time 5h (samples 11&23), pre-exsiting cytoplasmic mRNA time 7.5h (samples 12&24)
Publication Title
Comprehensive analysis of nucleocytoplasmic dynamics of mRNA in Drosophila cells.
Sample Metadata Fields
Cell line, Treatment, Subject
View Samples- Mus musculus
- 4 Downloadable Samples
- Illumina HiSeq 2000
Description
In mammals, the nuclear lamina interacts with hundreds of large genomic regions, termed lamina-associated domains (LADs) that are generally in a transcriptionally repressed state. Lamins form the major structural component of the lamina and have been reported to bind DNA and chromatin. Here we systematically evaluated whether lamins are necessary for the peripheral localization of LADs in murine embryonic stem cells. Surprisingly, removal of essentially all lamins did not have any detectable effect on the genome-wide interaction pattern of chromatin with the inner nuclear membrane. This suggests that other components of the inner nuclear membrane mediate these interactions. Overall design: 2 samples, each with a biological replicate: wt mESC, B type lamin null (dKO) dKO mESC
Publication Title
Nuclear lamins are not required for lamina-associated domain organization in mouse embryonic stem cells.
Sample Metadata Fields
No sample metadata fields
View Samples- Drosophila melanogaster
- 6 Downloadable Samples
- Illumina HiSeq 2000
Description
Dam identification (DamID) is a powerful technique to generate genome-wide maps of chromatin protein binding. Due to its high sensitivity it is particularly suited to study the genome interactions of chromatin proteins in small tissue samples in model organisms such as Drosophila. Here we report an intein-based approach to tune the expression level of Dam and Dam-fusion proteins in Drosophila by addition of a ligand to fly food. This helps to suppress toxic effects of Dam. In addition we describe a strategy for genetically controlled expression of Dam in a specific cell type in complex tissues. We demonstrate the utility of the latter by generating a glia-specific map of Polycomb in small samples of brain tissue. Overall design: RNA sequencing of 3 samples, each using 2 biological replicates.
Publication Title
Inducible DamID systems for genomic mapping of chromatin proteins in Drosophila.
Sample Metadata Fields
Sex, Specimen part, Subject
View Samples- Mus musculus
- 6 Downloadable Samples
- Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
The spatial organization of DNA in the cell nucleus is an emerging key contributor to genomic function. We have developed 4C technology, or 3C-on-chip, which allows for an unbiased genome-wide search for DNA loci that contact a given locus in the nuclear space. We demonstrate here that active and inactive genes are engaged in many long-range intrachromosomal interactions and can also form interchromosomal contacts. The active b-globin locus in fetal liver contacts mostly transcribed, but not necessarily tissue-specific, loci elsewhere on chromosome 7, while the inactive locus in fetal brain contacts different, transcriptionally silent, loci. A housekeeping gene in a gene dense region on chromosome 8 forms long-range contacts predominantly with other active gene clusters, both in cis and in trans, and many of these intra- and interchromosomal interactions are conserved between the tissues analyzed. Our data demonstrate that chromosomes fold into areas of active chromatin and areas of inactive chromatin and establish 4C technology as a powerful tool to study nuclear architecture.
Publication Title
Nuclear organization of active and inactive chromatin domains uncovered by chromosome conformation capture-on-chip (4C).
Sample Metadata Fields
Specimen part
View Samples- Homo sapiens
- 24 Downloadable Samples
- Illumina HiSeq 2000
Description
Background. Cellular senescence is a mechanism that virtually irreversibly suppresses the proliferative capacity of cells in response to various stress signals. This includes the expression of activated oncogenes, which cause Oncogene-Induced Senescence (OIS). A body of evidence points to the involvement of chromatin reorganization, including the formation of senescence-associated heterochromatic foci (SAHF). The nuclear lamina (NL) is an important contributor to genome organization and has been involved in cellular senescence and organismal aging. It interacts with multiple regions of the genome called lamina-associated domains (LADs). Some LADs are cell type-specific, while others are conserved between cell types and are referred to as constitutive LADs. Here, we used DamID to investigate the changes in genome-NL interactions in a model of OIS triggered by the expression of the BRAFV600E oncogene.Results. We found that OIS cells lose most of their constitutive LADs (cLADS), suggesting the loss of a specific mechanism that targets cLADs to the NL. In addition, multiple genes relocated to the NL. Unexpectedly, they were not repressed, implying the abrogation of the repressive activity of the NL during OIS. Finally, OIS cells displayed an increased association of telomeres with the NL.Conclusions. Our study reveals that senescent cells acquire a new type of LAD organization and suggest the existence of as yet unknown mechanisms that tether cLADs to the NL and repress gene expression at the NL.
Publication Title
Massive reshaping of genome-nuclear lamina interactions during oncogene-induced senescence.
Sample Metadata Fields
Specimen part, Cell line, Subject, Time
View Samples