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 SamplesEpidermal stem cells ensure that skin homeostasis is maintained. In murine skin, epidermal stem cells cluster at specific niches where, under steady-state conditions, they undergo cycles of dormancy and activation1. When cellular replenishment is required, epidermal stem cells egress from the niche and proliferate for a limited number of times to subsequently feed into the differentiated compartment1-3. However, only a subset of stem cells becomes active during each round of morphogenesis, suggesting that stem cells coexist in heterogeneous responsive states within the same niche. Using a circadian clock fluorescent reporter mouse model, we show that the dormant epidermal stem cell niche contains two coexisting populations of stem cells at opposite phases of the clock, which are differentially predisposed to respond to homeostatic cues. In dormant niches, the core molecular clock protein Bmal1 transcriptionally modulates the expression of stem cell regulatory genes, including modulators of Wnt and TGFb, to create two coexisting stem cell populations, one predisposed, and the other less prone, to activation. Unbalancing this equilibrium of epidermal stem cells, through conditional epidermal deletion of Bmal1, resulted in a long-term progressive accumulation of non-responsive stem cells, premature impairment of tissue self-renewal, and a significant reduction in the development of squamous cell carcinomas. Our results indicate that the molecular clock machinery fine-tunes the spatiotemporal behavior of epidermal stem cells within their niche, and that perturbation of this mechanism affects tissue homeostasis and the predisposition to neoplastic transformation. The goals of this study was to compare the transcriptome of epidermal stem cells according to their circadian rhythm phase. We isolated epidermal stem cells (bulge cells; alpha6bright/CD34+ population) from 19 days old Per1-Venus mice and separated them according to Venusbright (clock positive) and Venus dim (clock negative). The goals of this study was to compare the transcriptome of epidermal stem cells in which their circadian rhythm machinery has been perturbed by deleting the gene that encodes for Bmal1. We compared the transcriptomes of basal interfollicular epidermis cells (alpha6 integrin bright/CD34- cells) from the dorsal skin of 1 year old BmalKO mice and their respective control littermates. Each array corresponds to purified cells from approximately 5 mice.
The circadian molecular clock creates epidermal stem cell heterogeneity.
Specimen part
View SamplesmiR-132 and miR-212 are structurally-related microRNAs that have been found to exert powerful modulatory effects within the central nervous system (CNS). Notably, these microRNAs are tandomly processed from the same non-coding transcript, and share a common seed sequence: thus it has been difficult to assess the distinct contribution of each microRNA to gene expression within the CNS. Here, we employed a combination of conditional knockout and transgenic mouse models to examine the contribution of the miR-132/212 gene locus to learning and memory, and then to assess the distinct effects that each microRNA has on hippocampal gene expression. Using a conditional deletion approach, we show that miR-132/212 double knockout mice exhibit significant cognitive deficits in spatial memory, recognition memory, and in tests of novel object recognition. Next, we utilized transgenic miR-132 and miR-212 overexpression mouse lines and the miR-132/212 double knockout line explore the distinct effects of these two miRNAs on the transcriptional profile of the hippocampus. Illumina sequencing revealed that miR-132/212 deletion increased the expression of 1,138 genes; Venn analysis showed that 96 of these genes were also downregulated in mice overexpressing miR-132. Of the 58 genes that were decreased in animals overexpressing miR-212, only four of them were also increased in the knockout line. Functional gene ontology analysis of downregulated genes revealed significant enrichment of genes related to synaptic transmission, neuronal proliferation, and morphogenesis, processes known for their roles in learning, and memory formation. These data, coupled with previous studies, firmly establish a role for the miR-132/212 gene locus as a key regulator of cognitive capacity. Further, although miR-132 and miR-212 share a seed sequence, these data indicate that these miRNAs do not exhibit strongly overlapping mRNA targeting profiles, thus indicating that, these two genes may function in a complex, non-redundant manner to shape the transcriptional profile of the CNS. The dysregulation of miR-132/212 expression could contribute to signaling mechanisms that are involved in an array of cognitive disorders Overall design: Hippocampal mRNA was isolated from CaMKII-Cre::miR-132/212f/f, tTA::miR132, and tTA::miR212 animals, as well as their respective nontransgenic controls. cDNA from six animals was pooled into three independent biological replicates for each. Libraries were prepared according to the Illumina TruSeqTM Sample Preparation Guide and sequenced using an Illumina Genome Analyzer II. Sequences were aligned to the UCSC mm9 reference genome using Bowtie v0.12.7 and custom R scripts. The sequence data have been submitted to the NCBI Short Read Archive with accession number in progress. Relative abundance was measured in Fragments Per Kilobase of exon per Million fragments mapped using Cufflinks v1.2.
Targeted deletion of miR-132/-212 impairs memory and alters the hippocampal transcriptome.
Cell line, Subject
View SamplesThis array set was used to identify the genes that are highly expressed in the mouse suprachiasmatic nucleus (SCN). Because pharmacological inhibition of Gai/o activity with pertussis toxin hampers intercellular synchronization and causes dampened rhythms of the entire SCN, we hypothesized that member(s) of the Regulator of G protein Signaling (RGS) family might contribute to synchronized cellular oscillations in the SCN. To test this hypothesis, we surveyed all known mouse Rgs genes for their expression by using GeneChip and selected the genes that are highly expressed in the SCN for further analysis.
Circadian regulation of intracellular G-protein signalling mediates intercellular synchrony and rhythmicity in the suprachiasmatic nucleus.
Sex, Age, Specimen part, Disease, Treatment, Time
View SamplesThe eukaryotic translation initiation factor (eIF) 3a is described in various tumor entities as potential tumor marker involved in development and progression of cancer. eIF3a is the largest subunit of the eIF3 complex, a key functional entity in 80S establishment and translation initiation. We hypothesize that eIF3a is more a specific than global translation initiator and involved in signalling pathways that are frequently targeted in UBC therapy.
eIF3a is over-expressed in urinary bladder cancer and influences its phenotype independent of translation initiation.
Specimen part, Cell line, Treatment
View SamplesPulmonary vascular occlusions due to thromboemboli can result in pulmonary hypertension and right heart damage. Treatments to clear the vascular obstructions such as i.v. heparain or thrombolytics can resolve the hypertension but right ventricular damage often occurs first. Methods of protecting the right ventricle from hypertensive damage during the course of acute treatment to clear the thromboemboli are needed. Monocyte- and neutrophil-mediated inflammation and fibrosis are associated with chronic right ventricular damage but the pathways involved are not understood. A comprehesive survey of gene expression during chronic pulmonary embolism verses control rats has been conducted in this study.
Transcriptional changes in right ventricular tissues are enriched in the outflow tract compared with the apex during chronic pulmonary embolism in rats.
Sex
View SamplesThe elaboration of a quality oocyte is integrally linked to the correct developmental progression of cumulus cell phenotype. In humans and non-human primates, oocyte quality is diminished with in vitro maturation. To determine the changes in gene expression in rhesus monkey cumulus cells (CC) that occur during the final day prior to oocyte maturation and how these changes differ between in vitro and in vivo maturation (IVM and VVM), we completed a detailed comparison of transcriptomes using the Affymetrix gene array. We observe a large number of genes differing in expression when comparing IVM-CC and VVM-CC directly, but a much larger number of differences comparing the transitions from the pre-oocyte maturation to post- IVM and post-VVM state. We observe a truncation or delay in the normal pattern of gene regulation, but also remarkable compensatory changes in gene expression during IVM. Among the genes affected in cumulus cells by IVM are those that contribute to productive cell-cell interactions between cumulus cell and oocyte and between cumulus cells. Numerous genes involved in lipid metabolism are incorrectly regulated during IVM, and the synthesis of sex hormones appears not suppressed during IVM. We identify a panel of 24 marker genes, the expression of which should provide the foundation for understanding how IVM can be improved, for monitoring IVM conditions, and for diagnosing oocyte quality.
Extensive effects of in vitro oocyte maturation on rhesus monkey cumulus cell transcriptome.
Specimen part
View SamplesElevated levels of microRNA miR-155 represent a candidate pathogenic factor in chronic B-lymphocytic leukemia (B-CLL). In this study, we present evidence that MYB (v-myb myeloblastosis viral oncogene homolog) is overexpressed in a subset of B-CLL patients. MYB physically associates with the promoter of MIR155 host gene (MIR155HG, also known as BIC, B-cell integration cluster) and stimulates its transcription. This coincides with the hypermethylated histone H3K4 residue and spread hyperacetylation of H3K9 at MIR155HG promoter. Our data provide evidence of oncogenic activities of MYB in B-CLL that include its stimulatory role in MIR155HG transcription.
MYB transcriptionally regulates the miR-155 host gene in chronic lymphocytic leukemia.
Specimen part, Disease, Disease stage
View Samples