Status epilepticus (SE) is a life-threatening condition that can give rise to a number of neurological disorders, including learning deficits, depression, and epilepsy. Many of the effects of SE appear to be mediated by alterations in gene expression. To gain deeper insight into how SE affects the transcriptome, we employed the pilocarpine SE model in mice and Illumina-based high-throughput sequencing to characterize alterations in gene expression from the induction of SE, to the development of spontaneous seizure activity. While some genes were upregulated over the entire course of the pathological progression, each of the three sequenced time points (12-hour, 10-days and 6-weeks post-SE) had a largely unique transcriptional profile. Hence, genes that regulate synaptic physiology and transcription were most prominently altered at 12-hours post-SE; at 10-days post-SE, marked changes in metabolic and homeostatic gene expression were detected; at 6-weeks, substantial changes in the expression of cell excitability and morphogenesis genes were detected. At the level of cell signaling, KEGG analysis revealed dynamic changes within the MAPK pathways, as well as in CREB-associated gene expression. Notably, the inducible expression of several noncoding transcripts was also detected. These findings offer potential new insights into the cellular events that shape SE-evoked pathology. Overall design: cDNA from two animals was pooled into two independent biological replicates for each timepoint (ie. two sets of two animals per experimental group: control, 12 hours, 10 days, 6 weeks). Samples were sequenced using a Genome Analyzer II (GAII) at a concentration of 10pM in each lane. Base-calling was conducted with the standard Illumina Analysis Pipeline 1.0 (Firescrest-Bustard). Eight FASTQ sequence files (sequencing reads plus quality information) were generated and mapped to the mouse genome (UCSC mm9) using the Bowtie algorithm with default settings. A C++ program was used to count the number of uniquely mapped reads within exons of Ref-Seq genes (UCSC Genome Browser mm9 annotation).
Status epilepticus stimulates NDEL1 expression via the CREB/CRE pathway in the adult mouse brain.
Cell line, Subject, Time
View SamplesAnalysis of alterations in the hippocampus transcriptome caused by deletion of Mitogen Stress activated Kinase 1 (MSK1).
Mitogen- and Stress-Activated Protein Kinase 1 Regulates Status Epilepticus-Evoked Cell Death in the Hippocampus.
Specimen part
View SamplesPhenobarbital is a well studied xenobiotic compound. In this study, we describe the genomic responses in fruit flies and examine whether animals mutant for DHR96, an ortholog of xenobiotic nuclear receptors PXR and CAR, plays a role in mediating xenobiotic responses in Drosophila.
The DHR96 nuclear receptor regulates xenobiotic responses in Drosophila.
No sample metadata fields
View SamplesDHR96 plays a role in regulating xenobiotic responses in Drosophila. Using a gain-of-function approach we test whether DHR96 is sufficient to affect detoxification genes in the absence of a xenobiotic insult.
The DHR96 nuclear receptor regulates xenobiotic responses in Drosophila.
No sample metadata fields
View SamplesPurpose: The DBA/2J mouse is a model for secondary angle-closure glaucoma due to iris atrophy and pigment dispersion, which ultimately leads to increased intraocular pressure (IOP). We sought to correlate changes in retinal gene expression with glaucoma-like pathology by performing microarray analysis of retinal RNA from DBA/2J mice at 3 months before disease onset, and at 8 months, after IOP elevation. Methods: IOP was monitored monthly in DBA/2J animals by Tono-Pen and animals with normal (3 months) or elevated IOP (8 months) were identified. RNA was prepared from 3 individual retinas at each age, and the RNA was amplified and used to generate biotin-labeled probe for high density mouse Affymetrix arrays (U430.2). A subset of genes was selected for confirmation by quantitative RT-PCR using independent retina samples from DBA/2J animals at 3, 5 and 8 months of age, and compared to retinas from C57BL/6J control animals at 3 and 8 months. Results: There were changes in expression of 68 genes, with 32 genes increasing and 36 genes decreasing at 8 months versus 3 months. Upregulated genes were associated with immune response, glial activation, signaling and gene expression, while down-regulated genes included multiple crystallin genes. Significant changes in 9 upregulated genes and 2 downregulated genes were confirmed by quantitative RT-PCR, with some showing changes in expression by 5 months. Conclusions: DBA/2J retina shows evidence for glial activation and an immune-related response following IOP elevation, similar to what has been reported following acute elevation of IOP in other models.
Microarray analysis of retinal gene expression in the DBA/2J model of glaucoma.
Age
View SamplesWe used microarrays to understand the effect miR-155 has on osteoclast differentiation.
miRNA-based mechanism for the commitment of multipotent progenitors to a single cellular fate.
Cell line
View SamplesAnalysis of gene expression in 17 low-grade fibromyxoid sarcoma (LGFMS) samples compared to that of histologically similar tumors. LGFMS is characterized by the specific translocations t(7;16)(q33;p11) or t(11;16)(p11;p11) and corresponding fusion genes FUS-CREB3L2 or FUS-CREB3L1.
FUS-CREB3L2/L1-positive sarcomas show a specific gene expression profile with upregulation of CD24 and FOXL1.
Specimen part, Disease
View SamplesA functional part of the Dicer gene was knocked out from MEF using a conditional knockout strain
Determinants of targeting by endogenous and exogenous microRNAs and siRNAs.
No sample metadata fields
View SamplesEed (embryonic ectoderm development) is a core component of the Polycomb Repressive Complex 2 (PRC2) which catalyzes the methylation of histone H3 lysine 27 (H3K27). Trimethylated H3K27 (H3K27me3) can act as a signal for PRC1 recruitment in the process of gene silencing and chromatin condensation. Previous studies with Eed KO ESCs revealed a failure to down-regulate a limited list of pluripotency factors in differentiating ESCs. Our aim was to analyze the consequences of Eed KO for ESC differentiation. To this end we first analyzed ESC differentiation in the absence of Eed and employed in silico data to assess pluripotency gene expression and H3K27me3 patterns. We linked these data to expression analyses of wildtype and Eed KO ESCs. We observed that in wildtype ESCs a subset of pluripotency genes including Oct4, Nanog, Sox2 and Oct4 target genes progressively gain H3K27me3 during differentiation. These genes remain expressed in differentiating Eed KO ESCs. This suggests that the deregulation of a limited set of pluripotency factors impedes ESC differentiation. Global analyses of H3K27me3 and Oct4 ChIP-seq data indicate that in ESCs the binding of Oct4 to promoter regions is not a general predictor for PRC2-mediated silencing during differentiation. However, motif analyses suggest a binding of Oct4 together with Sox2 and Nanog at promoters of genes that are PRC2-dependently silenced during differentiation. In summary, our data further characterize Eed function in ESCs by showing that Eed/PRC2 is essential for the onset of ESC differentiation.
Polycomb protein EED is required for silencing of pluripotency genes upon ESC differentiation.
Specimen part, Cell line
View SamplesAdult BALB/c female mice were injected intraperitoneally with a single dose at 20 mg per kg of antisense oligonucleotide either against miR-29a (5-TAACCGATTTCAGATGGTGCTA-3) or against a scrambled sequence (5-TCATTGGCATGTACCATGCAGCT-3 Antisense oligonucleotides contained 2-O-methoxyethyl (2-MOE), 2-flouro (2-F) 2'-alpha-flouro units with a phosphorothioate backbone (Regulus Therapeutics). Six days following the injection, liver was isolated, total RNA was prepared as described above, and the RNA was amplified and biotinylated using the MessageAmp Premier kit (Ambion). Samples (n=4 each experimental and control) were hybridized to Affymetrix GeneChip Mouse Genome 430 2.0 Arrays in the Childrens Hospital of Philadelphia Nucleic Acids Core Facilityand analyzed with the assistance of the Penn Bioinformatics Core. Probe intensities were normalized using the GCRMA method and the significance of the log2-transformed, GCRMA-normalized signal intensities was determined using SAM
MicroRNA profiling identifies miR-29 as a regulator of disease-associated pathways in experimental biliary atresia.
Sex, Specimen part, Treatment
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