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GSE43334
Homo sapiens
12 Downloadable Samples
Affymetrix Human Exon 1.0 ST Array [transcript (gene) version (huex10st)
Description
Stringent regulation of the interferon signaling pathway is essential for maintaining the immune response to pathogens and tumors. The transcription factor STAT1 is a crucial mediator of this response. Here we show that hCAF1/CNOT7 regulates class I and II interferon pathways at different crucial steps. In resting cells hCAF1 can control STAT1 trafficking by interacting with the latent form of STAT1 in the cytoplasm. IFN treatment induces STAT1 release, suggesting that hCAF1 may shield cytoplasmic STAT1 from undesirable stimulation. Consistent, hCAF1 silencing enhances STAT1 basal promoter occupancy associated with increased expression of a subset of STAT1-regulated genes. Consequently, hCAF1 knockdown cells exhibit an increased protection against viral infection and reduced viral replication. Furthermore, hCAF1 participates in the extinction of the IFN signal, through its deadenylase activity, by speeding up the degradation of some STAT1-regulated mRNAs. Since abnormal and unbalanced JAK/STAT activation is associated with immune disorders and cancer, hCAF1 could play a major role in innate immunity and oncogenesis, contributing to tumor escape.
Publication Title
hCAF1/CNOT7 regulates interferon signalling by targeting STAT1.
Sample Metadata Fields
Cell line
View Samples- Homo sapiens
- 32 Downloadable Samples
- Affymetrix Human Exon 1.0 ST Array [transcript (gene) version (huex10st)
Description
Alternative promoters (APs) occur in >30% protein-coding genes and contribute to proteome diversity. However, large-scale analyses of AP regulation are lacking, and little is known about their potential physiopathologic significance. To better understand the transcriptomic impact of estrogens, which play a major role in breast cancer, we analyzed gene and AP regulation by estradiol in MCF7 cells using pan-genomic exon arrays. We thereby identified novel estrogen-regulated genes, and determined the regulation of AP-encoded transcripts in 150 regulated genes. In <30% cases, APs were regulated in a similar manner by estradiol, while in >70% cases, they were regulated differentially. The patterns of AP regulation correlated with the patterns of estrogen receptor (ER) and CCCTC-binding factor (CTCF) binding sites at regulated gene loci. Interestingly, among genes with differentially regulated APs, we identified cases where estradiol regulated APs in an opposite manner, sometimes without affecting global gene expression levels. This promoter switch was mediated by the DDX5/DDX17 family of ER coregulators. Finally, genes with differentially regulated promoters were preferentially involved in specific processes (e.g., cell structure and motility, and cell cycle). We show in particular that isoforms encoded by the NET1 gene APs, which are inversely regulated by estradiol, play distinct roles in cell adhesion and cell cycle regulation, and that their expression is differentially associated with prognosis in ER+ breast cancer. Altogether, this study identifies the patterns of AP regulation in estrogen-regulated genes, demonstrates the contribution of AP-encoded isoforms to the estradiol-regulated transcriptome, as well as their physiopathologic significance in breast cancer.
Publication Title
Estrogen regulation and physiopathologic significance of alternative promoters in breast cancer.
Sample Metadata Fields
Disease, Disease stage, Cell line, Time
View Samples- Homo sapiens
- 12 Downloadable Samples
- Affymetrix Human Exon 1.0 ST Array [transcript (gene) version (huex10st)
Description
Alternative 3-terminal exons, which use intronic polyadenylation sites, are generally unconserved and lowly expressed, while the main gene products end in the last exon of genes. In this study, we discover a class of human genes, where the last exon appeared recently during evolution, and the major gene product uses an alternative 3-terminal exon corresponding to the ancestral last exon of the gene. This novel class of alternative 3-terminal exons are down-regulated on a large scale by doxorubicin, a cytostatic drug targeting topoisomerase II, and play a role in cell cycle regulation, including centromere-kinetochore assembly. The RNA-binding protein, HuR/ELAVL1 is a major regulator of this specific set of alternative 3-terminal exons. HuR binding to the alternative 3-terminal exon in the pre-messenger RNA promotes its splicing, and is reduced by topoisomerase inhibitors. These findings provide new insights into the evolution, function and molecular regulation of alternative 3-terminal exons.
Publication Title
A recently evolved class of alternative 3'-terminal exons involved in cell cycle regulation by topoisomerase inhibitors.
Sample Metadata Fields
Cell line
View Samples- Homo sapiens
- 15 Downloadable Samples
- Affymetrix Human Exon 1.0 ST Array [probe set (exon) version (huex10st)
Description
T-cell clones were obtained by limiting dilution culture of PBMC of HTLV-1 carriers. Exon expression profiling was performed using Affymetrix exon array (Affymetrix Human Exon 1.0 ST Array) according to the manufacturer's instructions. Gene version of CEL files 01 to 12 are presented in GSE46518.
Publication Title
HTLV-1-infected CD4+ T-cells display alternative exon usages that culminate in adult T-cell leukemia.
Sample Metadata Fields
Specimen part
View Samples- Homo sapiens
- 6 Downloadable Samples
- Affymetrix Human Exon 1.0 ST Array [probe set (exon) version (huex10st)
Description
Pre-mRNA splicing is functionally coupled to transcription, and genotoxic stresses can enhance alternative exon inclusion by affecting elongating RNA polymerase II. We report here that various genotoxic stress inducers, including camptothecin, inhibit the interaction between EWS, an RNA polymerase II-associated factor, and YB-1, a spliceosome-associated factor. This results in the cotranscriptional skipping of several exons of the MDM2 gene encoding the main p53 ubiquitin-ligase. This reversible exon skipping participates in the timely regulation of MDM2 expression, and may contribute to the accumulation of p53 during stress exposure and its rapid shut off when stress is removed. Finally, a splicing-sensitive microarray identified numerous exons that are skipped in response to camptothecin and EWS/YB-1 depletion. These data demonstrate genotoxic stress-induced alteration of the communication between the transcriptional and splicing machineries, resulting in widespread exon skipping and playing a central role in the genotoxic stress response.
Publication Title
Cotranscriptional exon skipping in the genotoxic stress response.
Sample Metadata Fields
Specimen part, Cell line
View Samples- Homo sapiens
- 9 Downloadable Samples
- Affymetrix Human Exon 1.0 ST Array [transcript (gene) version (huex10st)
Description
Altered expression of microRNAs (miRNAs), an abundant class of small non-protein-coding RNAs that mostly function as negative regulators of protein-coding gene expression, is common in cancer. Here we analyze the regulation of miRNA expression in response to estrogen, a steroid hormone that is involved in the development and progression of breast carcinomas and that is acting via the estrogen receptors (ER) transcription factors. We set out to thoroughly describe miRNA expression, by using miRNA microarrays and real time RTPCR experiments, in various breast tumor cell lines in which estrogen signaling has been induced by 17-estradiol (E2). We show that the expression of a broad set of miRNAs decreases following E2 treatment in an ER-dependent manner. We further show that enforced expression of several of the repressed miRNAs reduces E2-dependent cell growth, thus linking expression of specific miRNAs with estrogen-dependent cellular response. In addition, a transcriptome analysis revealed that the E2-repressed miR-26a and miR-181a regulate many genes associated with cell growth and proliferation, including the progesterone receptor gene, a key actor in estrogen signaling. Strikingly, miRNA expression is also regulated in breast cancers of women who had received antiestrogen neoadjuvant therapy thereby showing an estrogen-dependent in vivo regulation of miRNA expression. Overall, our data indicates that the extensive alterations in miRNA regulation upon estrogen signalling pathway plays a key role in estrogen-dependent functions and highlights the utility of considering miRNA expression in the understanding of antiestrogen resistance of breast cancer.
Publication Title
Widespread estrogen-dependent repression of micrornas involved in breast tumor cell growth.
Sample Metadata Fields
Cell line
View Samples- Homo sapiens
- 12 Downloadable Samples
- Affymetrix Human Exon 1.0 ST Array [probe set (exon) version (huex10st)
Description
RNA helicases DDX5 and DDX17 are members of a large family of highly conserved proteins involved in gene expression regulation, although their in vivo targets and activities in biological processes like cell differentiation, that requires reprogramming of gene expression programs at multiple levels, are not well characterized. In this report, we uncovered a new mechanism by which DDX5 and DDX17 cooperate with hnRNP H/F splicing factors to define epithelial- and myoblast-specific splicing subprograms. We next observed that downregulation of DDX5 and DDX17 protein expression during epithelial to mesenchymal transdifferentiation and during myogenesis contributes to switching splicing programs during these processes. Remarkably, this downregulation is mediated by the production of microRNAs induced upon differentiation in a DDX5/DDX17-dependent manner. Since DDX5 and DDX17 also function as coregulators of master transcriptional regulators of differentiation, we propose to name these proteins master orchestrators of differentiation, that dynamically orchestrate several layers of gene expression.
Publication Title
RNA helicases DDX5 and DDX17 dynamically orchestrate transcription, miRNA, and splicing programs in cell differentiation.
Sample Metadata Fields
Specimen part, Cell line
View Samples- Homo sapiens
- 8 Downloadable Samples
- Affymetrix Human Exon 1.0 ST Array [transcript (gene) version (huex10st)
Description
5-Fluorouracil (5-FU) is a widely used chemotherapeutic drug in colorectal cancer. Previous studies showed that 5-FU modulates RNA metabolism and mRNA expression. In addition, it has been reported that 5-FU incorporates into the RNAs constituting the translational machinery and that 5-FU affects the amount of some mRNAs associated with ribosomes. However, the impact of 5-FU on translational regulation remains unclear. Using translatome profiling, we report that a clinically relevant dose of 5-FU induces a translational reprogramming in colorectal cancer cell lines. Comparison of mRNA distribution between polysomal and non-polysomal fractions in response to 5-FU treatment using microarray quantification identified 313 genes whose translation was selectively regulated. These regulations were mostly stimulatory (91%). Among these genes, we showed that 5-FU increases the mRNA translation of HIVEP2, which encodes a transcription factor whose translation in normal condition is known to be inhibited by mir-155. In response to 5-FU, the expression of mir-155 decreases thus stimulating the translation of HIVEP2 mRNA. Interestingly, the 5-FU-induced increase in specific mRNA translation was associated with reduction of global protein synthesis. Altogether, these findings indicate that 5-FU promotes a translational reprogramming leading to the increased translation of a subset of mRNAs that involves at least for some of them, miRNA-dependent mechanisms. This study supports a still poorly evaluated role of translational control in drug response.
Publication Title
Translational reprogramming of colorectal cancer cells induced by 5-fluorouracil through a miRNA-dependent mechanism.
Sample Metadata Fields
Treatment
View Samples- Homo sapiens
- 6 Downloadable Samples
- Affymetrix Human Exon 1.0 ST Array [probe set (exon) version (huex10st)
Description
Myotonic dystrophes (DM), the most common adult muscular dystrophy, are the first recognized examples of RNA-mediated diseases in which expression of mutant RNAs containing expanded CUG or CCUG repeats interfere with the splicing of other mRNAs. Using whole-genome microarrays, we found that alternative splicing of the BIN1 mRNA is altered in DM skeletal muscle tissues, resulting in the expression of an inactive form of BIN1 deprived of phosphoinositide-binding and membrane-tubulating activities. BIN1 is involved in tubular invaginations of the plasma membrane and is essential for biogenesis of the muscle T-tubules, which are specialized skeletal muscle membrane structures essential to correct excitation-contraction (E-C) coupling. Mutations in the BIN1 gene cause centronuclear myopathy (CNM) that shares some histopathological features with DM, and both diseases are characterized by muscle weakness. Consistent with a loss-of-function of BIN1, muscle T-tubules were altered in DM patients, and membrane tubulation was restored upon expression of the correct splicing form of BIN1 in DM muscle cells. By deciphering the mechanism of BIN1 splicing mis-regulation we demonstrate that the splicing regulator, MBNL1, which is sequestered by expanded CUG and CCUG in DM, binds the BIN1 pre-mRNA and regulates directly its alternative splicing. Finally, reproducing BIN1 splicing alteration in mice is sufficient to reproduce the DM features of T-tubule alterations and muscle weakness. We propose that alteration of BIN1 alternative splicing regulation leads to muscle weakness, a predominant pathological feature of DM.
Publication Title
Misregulated alternative splicing of BIN1 is associated with T tubule alterations and muscle weakness in myotonic dystrophy.
Sample Metadata Fields
Specimen part
View Samples- Homo sapiens
- 6 Downloadable Samples
IlluminaHiSeq2000
Description
Analysis of alternative splicing in heart (left ventricles) samples of 3 adult DM1 patients versus 3 adult controls Overall design: PolyA RNA from left ventricles (heart) of 3 controls and 3 DM1 patients were analysed by massive parrallel sequencing
Publication Title
Splicing misregulation of SCN5A contributes to cardiac-conduction delay and heart arrhythmia in myotonic dystrophy.
Sample Metadata Fields
No sample metadata fields
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