We use mice containing a gene trap in the first intron of the Rest gene, which effectively eliminates transcription from all coding exons, to prematurely remove REST from neural progenitors. We find catastrophic DNA damage that occurs during S-phase of the cell cycle and concominant with activation of p53 pro-apoptotic sgnalling, with consequences including abnormal chromosome separation, apoptosis, and smaller brains.
The REST remodeling complex protects genomic integrity during embryonic neurogenesis.
Specimen part
View SamplesWe use mice containing a gene trap in the first intron of the Rest gene, which effectively eliminates transcription from all coding exons, to prematurely remove REST from neural progenitors. We find catastrophic DNA damage that occurs during S-phase of the cell cycle, with consequences including abnormal chromosome separation, apoptosis, and smaller brains. Further support for persistent effects is the latent appearance of proneural glioblastomas in adult mice also lacking the tumor suppressor, p53. A Rest deficient mouse line generated previously, using a conventional gene targeting approach, does not exhibit these phenotypes, likely due to a remaining C terminal peptide that still binds chromatin and recruits REST chromatin modifiers.Our results indicate that REST-mediated chromatin remodeling is required for proper S-phase dynamics, prior to its well-established role in relieving repression of neuronal genes at terminal differentiation.
The REST remodeling complex protects genomic integrity during embryonic neurogenesis.
Specimen part
View SamplesThese experiments were designed to test the hypothesis that REST and Polycomb Repressor Complex 2 function cooperatively in undifferentiated ESCs. Our results show that H3K27me3-enriched genes show no de-repression in REST-/- ESCs, while REST target genes show significant de-repression. Overall design: RNA-seq was performed and analyzed using two biological replicates for each genotype, WT (N6) and REST-/- (N8) mouse embryonic stem cells.
Polycomb- and REST-associated histone deacetylases are independent pathways toward a mature neuronal phenotype.
No sample metadata fields
View SamplesRIPK4 but not the related kinases RIPK1, RIPK2, and RIPK3 caused similar transcriptional changes to Wnt3a. Overall design: PA1 cells were transfected by 8ug RIPK1, RIPK2, RIPK3, or RIPK4 for 48h, RNA were extracted and sequenced.
Phosphorylation of Dishevelled by protein kinase RIPK4 regulates Wnt signaling.
Cell line, Subject
View SamplesmiR-92 enhances c-Myc induced apoptosis. In the R26MER/MER mouse embryonic fibroblasts (MEFs), a switchable variant of Myc, MycERT2, was knocked into the genomic region downstream of the constitutive Rosa26 promoter, allowing acute activation of c-Myc by 4-OHT-induced nuclear translocation. This in vitro system nicely recapitulates c-Myc-induced apoptosis, as activated MycERT2 induces strong p53-dependent apoptosis in response to serum starvation. Enforced miR-92 expression in three independent R26MER/MER MEF lines significantly enhanced Myc-induced apoptosis.
A component of the mir-17-92 polycistronic oncomir promotes oncogene-dependent apoptosis.
Specimen part
View SamplesThis study investigates the effects of the aryl hydrocarbon receptor (AhR) ligands TCDD, PCB126 and PeCDF; the non-AhR ligand PCB153 and the binary mixture PCB126/PCB153 on hepatic gene expression in female sprague dawley rats. Rats were treated with toxicological equivalent doses of TCDD (100ng/kg), PeCDF (200ng/kg), PCB126 (1000ng/kg) and PCB153 (1000ug/kg) 5 days a week for 13 weeks.
Hepatic gene downregulation following acute and subchronic exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin.
Specimen part, Treatment
View SamplesMigrating schistosomula are an important stage of the schistosome lifecycle and represent a key target for elimination of infection by natural and vaccine induced host immune responses. To gain a better understanding of how these parasites initiate a primary host immune response we have characterised the host lung response to migrating Schistosoma japonicum schistosomula using a combination of histochemistry, microarrays and quantitative cytokine analysis. Our data suggest that, during a S. japonicum infection, actively migrating schistosomula induce a Type-2 cytokine response in the lung that may support the subsequent development of a CD4+ T helper 2 (Th2) response against egg antigens. This hypothesis is supported by the fact that schistosomula and schistosome eggs are known to express important Th2-inducing antigens such as omega-1, peroxiredoxin, kappa-5 and IPSE/alpha1. The host lung response to migrating schistosomula was associated with increased numbers of macrophages and expression of markers for alternatively activated macrophages (AAM) in the lung. Activation of AAM in the lung and at the systemic level could lead to the modulation of the host immune response to favour parasite survival. Induction of these cells could also contribute to diminished inflammatory responses to, for example, allergy and asthma that are known to be associated with helminth infections. These data enhance our understanding of the mechanisms whereby schistosomes may evade the immune response and the mechanisms by which schistosome infection can help influence the host response following exposure to allergenic stimuli.
Migrating Schistosoma japonicum schistosomula induce an innate immune response and wound healing in the murine lung.
Sex, Age, Specimen part
View SamplesHepatitis C Virus is a leading cause of chronic liver disease. The identification and characterisation of key host cellular factors that play a role in the HCV replication cycle is important for the understanding of disease pathogenesis and the identification of novel anti-viral therapeutic targets. Gene expression profiling of HCV infected Huh7 cells by microarray analysis was performed to identify host cellular genes that are transcriptionally regulated by infection. The expression of host genes involved in cellular defence mechanisms (apoptosis, proliferation and anti-oxidant responses), cellular metabolism (lipid and protein metabolism) and intracellular transport (vesicle trafficking and cytoskeleton regulation) was significantly altered by HCV infection. The gene expression patterns identified provide insight into the potential mechanisms that contribute to HCV associated pathogenesis. These include an increase in pro-inflammatory and pro-apoptotic signalling and a decrease in the anti-oxidant response pathways of the infected cell.
Gene expression profiling indicates the roles of host oxidative stress, apoptosis, lipid metabolism, and intracellular transport genes in the replication of hepatitis C virus.
Specimen part, Cell line
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.
No sample metadata fields
View SamplesTFH and Th1 cells generated after viral or intracellular bacterial infections are critical for the control of infections and the development of immunological memories. However, the mechanisms that govern the choice of activated CD4 T cells to the two alternative fates remain unclear. Here, we found that reciprocal expression of TCF1 and Blimp1 between viral-specific TFH and Th1 cells started early after infection. TCF1 was intrinsically required for the differentiation of TFH cells. In the absence of TCF1, TFH cells failed to maintain their transcriptional and metabolic signatures, distinct from those in Th1 cells. Mechanistically, TCF1 functioned through forming negative feedback loops with IL-2 and Blimp1 signaling. Thus, we have demonstrated an essential role of TCF1 in TFH-cell differentiation.
TCF1 Is Required for the T Follicular Helper Cell Response to Viral Infection.
Specimen part
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