Disruption of the MECP2 gene leads to Rett syndrome (RTT), a severe neurological disorder with features of autism. MECP2 encodes a methyl-DNA-binding protein that is proposed to function as a transcriptional repressor, but, despite numerous studies examining neuronal gene expression in MeCP2 mutants, no coherent model has emerged for how MeCP2 regulates transcription. Here we identify a genome-wide length-dependent increase in the expression of long genes in neurons lacking MeCP2. This gene misregulation occurs in human RTT brains and correlates with onset and severity of phenotypes in Mecp2 mutant mice, suggesting that the disruption of long gene expression contributes to RTT pathology. We present evidence that MeCP2 represses long genes by binding to brain-enriched, methylated CA dinucleotides within genes and show that loss of methylated CA in the brain recapitulates gene expression defects observed in MeCP2 mutants. We find that long genes encode proteins with neuronal functions, and overlap substantially with genes that have been implicated in autism and Fragile X syndrome. Reversing the overexpression of long genes in neurons lacking MeCP2 can improve some RTT-associated cellular deficits. These findings suggest that a function of MeCP2 in the mammalian brain is to temper the expression of genes in a length-dependent manner, and that mutations in MeCP2 and possibly other autism genes may cause neurological dysfunction by disrupting the expression of long genes in the brain. Overall design: Total RNA-seq Data from the visual cortex of wild-type and MeCP2 knockout animals at 8-10 weeks of age
Disruption of DNA-methylation-dependent long gene repression in Rett syndrome.
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View SamplesComparison between cell lines from 9 different cancer tissue of origin types (Breast, Central Nervous System, Colon, Leukemia, Melanoma, Non-Small Cell Lung, Ovarian, Prostate, Renal) from NCI-60 panel
Exon array analyses across the NCI-60 reveal potential regulation of TOP1 by transcription pausing at guanosine quartets in the first intron.
Sex, Age, Specimen part, Cell line
View SamplesComparison between cell lines from 9 different cancer tissue of origin types (Breast, Central Nervous System, Colon, Leukemia, Melanoma, Non-Small Cell Lung, Ovarian, Prostate, Renal) from NCI-60 panel.
Topoisomerase I levels in the NCI-60 cancer cell line panel determined by validated ELISA and microarray analysis and correlation with indenoisoquinoline sensitivity.
Sex, Age, Specimen part, Cell line
View SamplesGene expression from pre- and post- Cediranib treated patients with metastatic Alveolar Soft Part Sarcoma (ASPS)
Cediranib for metastatic alveolar soft part sarcoma.
Time
View SamplesExposure to high irradiance results in dramatic changes in nuclear gene expression in plants. However, little is known about the mechanisms by which changes in irradiance are sensed and how the information is transduced to the nucleus to initiate the genetic response. To investigate whether the photoreceptors are involved in the response to high irradiance, we analyzed expression of ELIP1, ELIP2, APX2 and LHCB2.4 in the phyA, phyB, cry1 and cry2 photoreceptor mutants and hy5 and hyh transcription factor mutants. Following exposure to high intensity white light for 3 h (HL, 1000 micro mol quanta m-2 s-1) expression of ELIP1/2 and APX2 was strongly induced and LHCB2.4 expression repressed in wild type. The cry1 and hy5 mutants showed specific mis-regulation of ELIP1/2 and we show that the induction of ELIP1/2 expression is mediated via CRY1 in a blue light intensity-dependent manner. Furthermore, using the Affymetrix Arabidopsis 24K Gene-Chip we showed that 77 of the HL responsive genes are regulated via CRY1, and 26 of those genes were also HY5 dependent. As a consequence of the mis-regulation of these genes the cry1 mutant displayed a high irradiance-sensitive phenotype with significant photoinactivation of PSII, indicated by reduced Fv/Fm. Thus, we describe a novel function of CRY1 in mediating plant responses to high irradiances that is essential to the induction of photoprotective mechanisms. This indicates that high irradiance can be sensed in a chloroplast-independent manner by a cytosolic/nucleic component.
Genome-wide gene expression analysis reveals a critical role for CRYPTOCHROME1 in the response of Arabidopsis to high irradiance.
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View SamplesThe transcriptome of zebrafish embryos treated with a Nodal signaling inhibitor at sphere stage, which causes neural tube defects, is compared to those treated at 30% epiboly, which does not. Overall design: Transcriptomic analysis of differential gene expression of key developmental pathways under differing inhibitory treatments.
Identification of transcripts potentially involved in neural tube closure using RNA sequencing.
No sample metadata fields
View SamplesOsteoblasts are key players in bone remodeling. The accessibility of human primary osteoblast-like cells (HOb) from bone explants render them a lucrative model for studying molecular physiology of bone turnover, discovery of novel anabolic therapeutics and mesenchymal cell biology in general. Relatively little is known about resting and dynamic expression profiles of HObs and no studies have been conducted to date to systematically assess the osteoblast transcriptome. The aim of this study was to characterize HObs and investigate signaling cascades and gene networks using genomewide expression profiling in resting and Bone Morphogenic Protein (BMP)-2 and Dexamethasone induced cells.
Systematic assessment of the human osteoblast transcriptome in resting and induced primary cells.
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View SamplesExcessive mRNA translation downstream of group I metabotropic glutamate receptors (mGlu1/5) is a core pathophysiology of fragile X syndrome (FX), however the differentially translating mRNAs that contribute to altered neural function are not known. We used Translating Ribosome Affinity Purification (TRAP) and RNA-seq to identify mistranslating mRNAs in CA1 pyramidal neurons of the FX mouse model (Fmr1-/y) hippocampus, which exhibit exaggerated mGlu1/5-induced long-term synaptic depression (LTD). In these neurons, we find the Chrm4 transcript encoding muscarinic acetylcholine receptor 4 (M4) is excessively translated, and synthesis of M4 downstream of mGlu5 activation is mimicked and occluded. Surprisingly, enhancement rather than inhibition of M4 activity normalizes core phenotypes in the Fmr1-/y, including excessive protein synthesis, exaggerated mGluR-LTD, and audiogenic seizures. These results suggest that not all excessively translated mRNAs in the Fmr1-/y brain are detrimental, and some may be candidates for enhancement to correct pathological changes in the FX brain. Overall design: 6 biological replicates of total hippocampal mRNA (Input) from WT and Fmr1 KO littermate pairs and CA1-TRAP-IP (IP) from the same 6 WT and KO littermate pairs.
Cell-Type-Specific Translation Profiling Reveals a Novel Strategy for Treating Fragile X Syndrome.
Sex, Specimen part, Cell line, Subject
View SamplesZaire ebolavirus (ZEBOV) infections are associated with high lethality in primates. ZEBOV primarily targets mononuclear phagocytes, which are activated upon infection and secrete mediators believed to trigger initial stages of pathogenesis. The characterization of the responses of target cells to ZEBOV infection may therefore not only further understanding of pathogenesis but also suggest possible points of therapeutic intervention. Gene expression profiles of primary human macrophages exposed to ZEBOV were determined using DNA microarrays and quantitative PCR to gain insight into the cellular response immediately after cell entry. Significant changes in mRNA concentrations encoding for 88 cellular proteins were observed. Most of these proteins have not yet been implicated in ZEBOV infection. Some, however, are inflammatory mediators known to be elevated during the acute phase of disease in the blood of ZEBOV-infected humans. Interestingly, the cellular response occurred within the first hour of Ebola virion exposure, i.e. prior to virus gene expression. This observation supports the hypothesis that virion binding or entry mediated by the spike glycoprotein (GP1,2) is the primary stimulus for an initial response. Indeed, ZEBOV virions, LPS, and virus-like particles consisting of only the ZEBOV matrix protein VP40 and GP1,2 (VLPVP40-GP) triggered comparable responses in macrophages, including pro-inflammatory and pro-apoptotic signals. In contrast, VLPVP40 (particles lacking GP1,2) caused an aberrant response. Notably, some cellular interferon-inducible genes were upregulated six hours after exposure to virions and LPS, but not after exposure to VLPVP40-GP. This suggests that GP1,2 binding to macrophages plays an important role in the immediate cellular response.
Ebola virion attachment and entry into human macrophages profoundly effects early cellular gene expression.
Disease, Disease stage, Subject
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Global analysis of the impact of environmental perturbation on cis-regulation of gene expression.
Sex, Specimen part, Time
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