IPH-926 is an anticancer drug-resistant tumor cell line derived from a chemo-refractory human infiltrating lobular breast cancer (ILBC). IPH-926 ILBC cells were subjected to gene expression profiling using an Affymetrix HG U133 Plus 2.0 array.
ABCB1/MDR1 contributes to the anticancer drug-resistant phenotype of IPH-926 human lobular breast cancer cells.
Specimen part, Cell line
View SamplesPromoter-proximal pausing of RNA polymerase II (Pol II) is a widespread transcriptional regulatory step across metazoans. Here we find that the nuclear exon junction complex (pre-EJC) is a critical and conserved regulator of this process. Depletion of pre-EJC subunits leads to a global decrease in Pol II pausing and to premature entry into elongation. This effect occurs, at least in part, via non-canonical recruitment of pre-EJC components at promoters. Failure to recruit the pre-EJC at promoters results in increased binding of the positive transcription elongation complex (P-TEFb) and in enhanced Pol II release. Notably, restoring pausing is sufficient to rescue exon skipping and the photoreceptor differentiation defect associated with depletion of pre-EJC components in vivo. We propose that the pre-EJC serves as an early transcriptional checkpoint to prevent premature entry into elongation, ensuring proper recruitment of RNA processing components that are necessary for exon definition. Overall design: polyA mRNA -seq in conditions with the indicated knockdown treatments
Promoter-proximal pausing mediated by the exon junction complex regulates splicing.
Specimen part, Cell line, Subject
View SamplesThe exon junction complex (EJC) is a highly conserved ribonucleoprotein complex which binds RNAs at a late stage of the splicing reaction and remains associated following export to the cytoplasm. This complex is involved in several cellular post-transcriptional processes including mRNA localization, translation and degradation. The EJC plays an additional role in the splicing of a subset of genes in Drosophila and in human cells but the underlying mechanism remains to be elucidated. Here, we have found a novel function for the EJC and its splicing subunit RnpS1 in preventing transposon accumulation in both Drosophila germline and surrounding follicular cells. This function is mediated specifically through the control of the splicing of the piwi transcript. In absence of RnpS1 one of the piwi intron is retained. This intron contains a weak 5’ splice site as well as degenerate transposon fragments, reminiscent of heterochromatic introns. In addition, we identified a small A/T rich region, which alters its polypyrimidine tract (PPT) and confers the RnpS1’s dependency. Finally, we showed that the removal of this intron by RnpS1 requires the initial splicing of the flanking introns, suggesting a model in which the EJC facilitates the splicing of challenging introns following its initial deposition to adjacent exon junctions. Overall design: In total there are 4 different conditions. Comparisons were made between piwi mutant vs control piwi and rnps1 KD vs controls RnpS1
The exon junction complex controls transposable element activity by ensuring faithful splicing of the piwi transcript.
Specimen part, Subject
View SamplesHuman solid tumors contain rare cancer side population (SP) cells, which expel the fluorescencent dye H33342 and display cancer stem cell characteristics. Transcriptional profiling of cancer SP cells isolated by H33342 fluorescence analysis is a newly emerging approach to discover cancer stem cell markers and aberrant differentiation pathways. Using Affymetrix expression microarrays this study investigated differential gene expression between SP and non-SP (NSP) cells isolated from the CAL-51 human mammary carcinoma cell line.
Down-regulation of the fetal stem cell factor SOX17 by H33342: a mechanism responsible for differential gene expression in breast cancer side population cells.
Specimen part
View SamplesN6-methyladenosine RNA (m6A) is the most abundant internal mRNA modification in mammals. While its role in the regulation of posttranscriptional gene expression is beginning to be unveiled, its function during development of complex organisms is poorly understood. Here, we identify Spenito as a novel member of the methyltransferase complex and show that m6A in Drosophila is necessary for proper synaptic growth, and in regulation of early steps of pre-mRNA splicing. Splicing of Sex-lethal and of its downstream targets are defective in animals lacking m6A, revealing also important roles in sex determination and dosage compensation. Finally, we implicate the nuclear m6A reader protein, YT521-B, as a crucial effector of m6A modifications in vivo. Altogether, our work provides important novel insights into m6A biology through identification and characterization of both m6A-writing and -reading proteins in Drosophila and their effects on splicing, neurogenesis and sex-determination within the context of the whole animal. Overall design: RNA seq in Drosophila melanogaster (flies) (3 Conditions, triplicates)
m<sup>6</sup>A modulates neuronal functions and sex determination in Drosophila.
Sex, Specimen part, Subject
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Reconstruction of phrenic neuron identity in embryonic stem cell-derived motor neurons.
Specimen part
View SamplesExpression response after induction of putative phrenic neuronal determinants in ES cell-derived motor neurons was compared to a pre-determined list of genes over-expressed in FACS-sorted primary.
Reconstruction of phrenic neuron identity in embryonic stem cell-derived motor neurons.
Specimen part
View SamplesExpression response after induction of putative phrenic neuronal determinants in ES cells was compared to a pre-determined list of genes over-expressed in FACS-sorted phrenic cells.
Reconstruction of phrenic neuron identity in embryonic stem cell-derived motor neurons.
Specimen part
View SamplesThe tissue-specific pattern of mRNA expression can indicate important clues about gene function. High-density oligonucleotide arrays offer the opportunity to examine patterns of gene expression on a genome scale. Toward this end, we have designed custom arrays that interrogate the expression of the vast majority of protein-encoding human and mouse genes and have used them to profile a panel of 79 human and 61 mouse tissues. The resulting data set provides the expression patterns for thousands of predicted genes, as well as known and poorly characterized genes, from mice and humans. We have explored this data set for global trends in gene expression, evaluated commonly used lines of evidence in gene prediction methodologies, and investigated patterns indicative of chromosomal organization of transcription. We describe hundreds of regions of correlated transcription and show that some are subject to both tissue and parental allele-specific expression, suggesting a link between spatial expression and imprinting.
A gene atlas of the mouse and human protein-encoding transcriptomes.
No sample metadata fields
View SamplesNeutrophil lysis after phagocytosis is a process potentially important in the pathogenesis of community-associated methicillin-resistant S. aureus (CA-MRSA) infection. The mechanism for this process is not currently known. Therefore, to better understand CA-MRSA virulence we used human oligonucleotide microarrays to investigate the mechanism underlying enhanced PMN lysis that occurs after phagocytosis of CA-MRSA.
Rapid neutrophil destruction following phagocytosis of Staphylococcus aureus.
Specimen part, Treatment
View Samples