Expression profile for undifferentiated F9 Embryonal Carcinoma cell line
Identification of active transcriptional regulatory modules by the functional assay of DNA from nucleosome-free regions.
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View SamplesAbf1 and Rap1 are General Regulatory Factors that contribute to transcriptional activation of a large number of genes, as well as to replication, silencing, and telomere structure in yeast. In spite of their widespread roles in transcription, the scope of their functional targets genome-wide has not been previously determined. We have used microarrays to examine the contribution of these essential GRFs to transcription genome-wide, by using ts mutants that dissociate from their binding sites at 37 C. We combined this data with published ChIP-chip studies and motif analysis to identify probable direct targets for Abf1 and Rap1. We also identified a substantial number of genes likely to bind Rap1 or Abf1, but not affected by loss of GRF binding. Interestingly, the results strongly suggest that Rap1 can contribute to gene activation from farther upstream than can Abf1. Also, consistent with previous work, more genes that bind Abf1 are unaffected by loss of binding than those that bind Rap1. Finally, we showed for several such genes that the Abf1 C-terminal region, which contains the putative activation domain, is not needed to confer this peculiar "memory effect" that allows continued transcription after loss of Abf1 binding.
Genome-wide analysis of transcriptional dependence and probable target sites for Abf1 and Rap1 in Saccharomyces cerevisiae.
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View SamplesThis study provides a framework describing how magnetic exposure is transduced from the most-plausible molecular-level biosensor (lipid membranes) to cell-level responses that include differentiation toward neural lineages. In addition, SMF provided a stimulus that uncovered new relationships that exist even in the absence of magnetic fields between gangliosides, the time dependent regulation of IL-6 signaling by these glycolipids, and the fate of embryonic cells.
Moderate strength (0.23-0.28 T) static magnetic fields (SMF) modulate signaling and differentiation in human embryonic cells.
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View SamplesThis study identified genomwide KCl inducible readthrough transcription. The project also includes a Cap-Seq experiment to identify transcriptional start sites, demonstrating that KCl does not activate downstream transcriptional start sites, but indeed does induce readthrough
Widespread Inducible Transcription Downstream of Human Genes.
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View SamplesThese cultures were grown to examine the differences in Agr-regulated virulence factor gene expression between wild-type S. aureus FRI1169 and a non-hemolytic variant isolated from a biofilm inoculated with FRI1169. The study is described more thoroughly in the paper "Generation of virulence factor variants in Staphylococcus aureus biofilms", Yarwood et al., J. Bacteriol. 2007.
Generation of virulence factor variants in Staphylococcus aureus biofilms.
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View SamplesRNA localization is a regulatory mechanism that is conserved from bacteria to mammals. Yet, little is known about the mechanism and the logic that govern the distribution of RNA transcripts within the cell. Here we present a novel organ culture system, which enables the isolation of RNA specifically from NGF dependent re-growing peripheral axons of mouse embryo sensory neurons. In combination with massive parallel sequencing technology, we determine the sub-cellular localization of most transcripts in the transcriptome. We found that the axon is enriched in mRNAs that encode secreted proteins, transcription factors and the translation machinery. In contrast, the axon was largely depleted from mRNAs encoding transmembrane proteins, a particularly interesting finding, since many of these gene products are specifically expressed in the tip of the axon at the protein level. Comparison of the mitochondrial mRNAs encoded in the nucleus with those encoded in the mitochondria, uncovered completely different localization pattern, with the latter much enriched in the axon fraction. This discovery is intriguing since the protein products encoded by the nuclear and mitochondrial genome form large co-complexes. Finally, focusing on alternative splice variants that are specific to axonal fractions, we find short sequence motifs that are enriched in the axonal transcriptome. Together our findings shed light on the extensive role of RNA localization and its characteristics. Overall design: For each RNA sample, Spinal Cords\ DRGs were dissected from 40 E13.5 embryos and cultured for 48H. Total RNA was extracted from whole DRG and Peripheral axons. Poly-A enriched. In duplicates, using GAIIx. Read length - 80nt.
Subcellular transcriptomics-dissection of the mRNA composition in the axonal compartment of sensory neurons.
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View SamplesTo investigate the systemic molecular changes occurring as a result of Dhr96 knockdown or over-expression, a comparison between knockdown or overexpression lines and their genetic controls were performed. 0-3 day old adult males or females were reared on 3 separate batches of diet (this was the standard diet we used for culturing Drosophila melanogaster and was made up of 10L water, 100g agar (USP #7060 Bio-serve), 350g Brewers dried yeast (Sunshine Health), 300g black treacle (Lyles), 150g sucrose (Tate & Lyle), 300g Difco dextrose (Becton Dickinson), 150g cornmeal (#1151, Bioserve), 100g wheatgerm (#1659, Bioserve), 200g soya bean flour (#S9633 Sigma Aldrich), 10g methyl-4-hydroxybenzoate (#H3647 Sigma Aldrich) in 10ml ethanol, 50ml proprionic acid (#P5561 Sigma Aldrich)). Each of these 3 batches was considered to represent independent biological replication. The RNA samples were hybridized to the Affymetrix Drosophila GeneChip 2.
Insecticide detoxification indicator strains as tools for enhancing chemical discovery screens.
Sex, Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Insecticide detoxification indicator strains as tools for enhancing chemical discovery screens.
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View SamplesTo test whether other genes were being silenced in the Cyp6g1 knockdown strain due to off-target RNAi effects, and whether other gene expression changes were contributing to the altered susceptibility to imidacloprid in these knockdown flies. A comparison between w;Act5C-GAL4/CyO; UAS:RNAi_Cyp6g1Hp2/TM3Sb and the genetic control w;Act-GAL4/CyO;+/TM3Sb was performed. Ten 2-3 day old adult males or females were transferred to sugar-agar plates and then collected at various time points (0, 2, 5, 8 hours). The RNA samples for up to three independent experiments per timepoint for each genotype were then pooled, in equal concentrations, before hybridisation to the Affymetrix Drosophila GeneChip 1.
Insecticide detoxification indicator strains as tools for enhancing chemical discovery screens.
Sex, Specimen part, Time
View SamplesMicroRNAs (miRNAs) are single-stranded non-coding RNAs that negatively regulate target gene expression through mRNA cleavage or translational repression. There is mounting evidence that they play critical roles in heart disease. The expression of known miRNAs in the heart has been studied at length by microarray and quantitative PCR but it is becoming evident that microRNA isoforms (isomiRs) are potentially physiologically important. It is well known that left ventricular (patho)physiology is influenced by transmural heterogeneity of cardiomyocyte phenotype, and this likely reflects underlying heterogeneity of gene expression. Given the significant role of miRNAs in regulating gene expression, knowledge of how the miRNA profile varies across the ventricular wall will be crucial to better understand the mechanisms governing transmural physiological heterogeneity. To determinine miRNA/isomiR expression profiles in the rat heart we investigated tissue from different locations across the left ventricular wall using deep sequencing. We detected significant quantities of 145 known rat miRNAs and 68 potential novel orthologs of known miRNAs, in mature, mature* and isomiR formation. Many isomiRs were detected at a higher frequency than their canonical sequence in miRBase and have different predicted targets. The most common miR-133a isomiR was more effective at targeting a construct containing a sequence from the gelsolin gene than was canonical miR-133a, as determined by dual-fluorescence assay. We identified a novel rat miR-1 homolog from a second miR-1 gene; and a novel rat miRNA similar to miR-676. We also cloned and sequenced the rat miR-486 gene which is not in miRBase (v18). Signalling pathways predicted to be targeted by the most highly detected miRNAs include Ubiquitin-mediated Proteolysis, Mitogen-Activated Protein Kinase, Regulation of Actin Cytoskeleton, Wnt signalling, Calcium Signalling, Gap junctions and Arrhythmogenic Right Ventricular Cardiomyopathy. Most miRNAs are not expressed in a gradient across the ventricular wall, with exceptions including miR-10b, miR-21, miR-99b and miR-486. Overall design: The hearts of 3 male 8 month old Sprague-Dawley rats were rapidly extracted after euthanasia with sodium pentobarbital. A section of the free wall of the left ventricle was dissected into epicardium, mid-myocardium and endocardium by cutting approximately 1 mm from the epicardial and endocardial surfaces. Small RNA was extracted (miRNeasy Kit; Qiagen, Crawley UK), quantified (Nanodrop; Thermo Scientific) and quality assessed for degradation (RNA Nano Chip, Bioanalyser 2100; Aligent Technologies, Wokingham UK; only samples with a RNA integrity no. (RIN) =8 were carried forward) and retention of small RNA (Small RNA Chip, Bioanalyser 2100). Small RNA was preferentially ligated with adapters, reverse transcribed into cDNA and amplified with 9 individually tagged primer indices (TruSeq Small RNA Sample Preparation Kit; Illumina, Little Chesterford, UK) and a library of small RNA created for each sample. After gel purification the cDNA products were again analysed on the bioanalyser using a High Sensitivity DNA Chip and assessed for the presence and concentration of the peak corresponding to ligated and tagged miRNA (approximately 147nt). Only samples with suitable RIN values exhibiting good retention of small RNA species were used for library preparation. After pooling, the samples were sequenced by TrinSeq (Trinity Genome Sequencing Lab & Neuropsychiatric Genetics Group, Trinity College Dublin, Ireland (http://www.medicine.tcd.ie/sequencing); using TruSeq SR Cluster Kit v5 (Illumina) and the resultant data trimmed and aligned to miRBase v18 (CLC Genomics Workbench v4.0; CLC bio, Swansea UK).
Distinctive profile of IsomiR expression and novel microRNAs in rat heart left ventricle.
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