Gene expression profiling of zebrafish early eye development on 3 to 5 days post fertilization (dpf)
Integrating multiple genome annotation databases improves the interpretation of microarray gene expression data.
Specimen part
View SamplesThe innate immune system is a two-edged sword; it is absolutely required for host defense against infection, but if left uncontrolled can trigger a plethora of inflammatory diseases. Here we used systems biology approaches to predict and validate a gene regulatory network involving a dynamic interplay between the transcription factors NF-B, C/EBP, and ATF3 that controls inflammatory responses. We mathematically modeled transcriptional regulation of Il6 and Cebpd genes and experimentally validated the prediction that the combination of an initiator (NF-B), an amplifier (C/EBP) and an attenuator (ATF3) forms a regulatory circuit that discriminates between transient and persistent Toll-like receptor 4-induced signals. Our results suggest a mechanism that enables the innate immune system to detect the duration of infection and to respond appropriately.
Function of C/EBPdelta in a regulatory circuit that discriminates between transient and persistent TLR4-induced signals.
Sex, Specimen part
View SamplesPosterior embryonic axis develops from neuromesodermal progenitors which differentiate into neural tube and paraxial mesoderm
Recapitulating early development of mouse musculoskeletal precursors of the paraxial mesoderm <i>in vitro</i>.
Treatment
View SamplesCocaine-mediated repression of the histone methyltransferase (HMT) G9a has recently been implicated in transcriptional, morphological, and behavioral responses to chronic cocaine administration. Here, using a ribosomal affinity purification approach, we find that G9a repression by cocaine occurs in both Drd1 (striatonigral)- and Drd2 (striatopallidal)-expressing medium spiny neurons (MSNs). Conditional knockout and overexpression of G9a within these distinct cell types, however, reveals divergent behavioral phenotypes in response to repeated cocaine treatment. Our studies further indicate that such developmental deletion of G9a selectively in Drd2 neurons results in the unsilencing of transcriptional programs normally specific to striatonigral neurons, and the acquisition of Drd1-associated projection and electrophysiological properties. This partial striatopallidal to striatonigral switching phenotype in mice indicates a novel role for G9a in contributing to neuronal subtype identity, and suggests a critical function for cell-type specific histone methylation patterns in the regulation of behavioral responses to environmental stimuli.
G9a influences neuronal subtype specification in striatum.
Sex, Specimen part
View SamplesTo gain insight into the changes in gene expression pattern upon Ebola infection, CD45+/+ (100% protein level) and CD45+/- (62% protein level) mice were challenged with mouse adapted Ebola virus. At time-points day 0, 1, 3, 5, 7, 9, 11 and 13, spleen tissue was harvested and splenocytes isolated. Total RNA was isolated for mRNA expression analysis. The mouse genome 430 2.0 array (Affymetrix, Inc.), which consists of over 39,000 genes in a single array, was used. Based on gene expression patterns, the variable genes were grouped into sixteen clusters. Each cluster contained genes associated with cellular immune processes, signaling, cell-cycle, complement coagulation cascade, biosynthesis/metabolism, ubiquitous genes involved in several cascades, and genes of unknown function. Interestingly, gene expression in clusters 2 and 3 were significantly downregulated by day 1 following EBOV challenge in CD45100% mice. In contrast, at day 1 following EBOV infection, the CD45 62% mice maintained gene expression patterns similar to day 0. The differences in gene expression patterns between the CD45 100% and CD45 62% splenocytes were less apparent at day 3 following infection and by days 5 and 7 they became very similar. At day 9, when wild-type mice had succumbed to the disease, the pattern in CD45 62% mice remained similar to the day 7 patterns of CD45 100% and CD45 62% mice. The pattern at days 11 and 13 in the CD45 62% mice had returned to that of day 0 CD45 100% or CD45 62% mice. These results suggested that in CD45 100% mice, subversion of the cell transcriptional machinery during the early stages of EBOV infection (day 1) might represent a major factor leading to death of the mice. In CD45 62% mice, early control of gene regulation likely provided the appropriate antiviral responses leading to regulated inflammation, immune co-stimulation, and survival.
Reduced levels of protein tyrosine phosphatase CD45 protect mice from the lethal effects of Ebola virus infection.
Specimen part
View SamplesAffymetrix Human Gene 1.1 ST Array profiling of 285 primary medulloblastoma samples.
Subgroup-specific structural variation across 1,000 medulloblastoma genomes.
Sex, Age
View SamplesAs a critical cellular stress sensor, p53 mediates a variety of defensive processes including cell-cycle arrest, apoptosis, and senescence to prevent propagation of hyperproliferative cells or cells with a damaged genome, hence the formation of neoplasia. Transactivation of downstream genes plays an important while sometimes controversial role in regulating these cellular processes. To evaluate the dependence on transcriptional activation in p53s activities, we generated genetically-modified mouse lines carrying mutations in the transactivation domains (TADs) of p53. These transactivatio-deficient mutants serve as unique reagents to probe the dependence on robust transactivation in p53-mediated cellular functions, as well as the underneath mechanisms. To identify genes differentially regulated by these p53 mutants, we performed gene expression profiling analysis on mouse embryonic fibroblast cells (MEFs) from these mice in the context of oncogenic Ras-induced premature cellular senescence.
Distinct p53 transcriptional programs dictate acute DNA-damage responses and tumor suppression.
Specimen part
View Samplesprenatal stress response, genetic modification
Differential effects of prenatal stress in 5-Htt deficient mice: towards molecular mechanisms of gene × environment interactions.
Sex, Specimen part, Treatment
View SamplesBarrier integrity is central to the maintenance of a healthy immunological homeostasis. Impaired skin barrier function is linked with enhanced allergen sensitization and the development of diseases such as atopic dermatitis (AD), which can precede the development of other allergic diseases such as food allergies and asthma. Epidemiological evidence indicates that children suffering from allergies have lower levels of dietary fibre-derived short-chain fatty acids (SCFA). Using an experimental model of AD, we report that a fermentable fibre-rich diet alleviates AD severity and systemic allergen sensitization. The gut-skin axis underpins this phenomenon through SCFA, which strengthen skin barrier integrity by altering mitochondrial metabolism of epidermal keratinocytes. SCFA promote keratinocyte differentiation and the production of key structural lipids, resulting in enhanced barrier function. Our results demonstrate that dietary fibre and SCFA mitigate AD by improving barrier integrity, ultimately limiting early systemic allergen sensitization and development of disease. Overall design: 16 Samples, 4 groups in duplicate
Gut-derived short-chain fatty acids modulate skin barrier integrity by promoting keratinocyte metabolism and differentiation.
Genotype, Disease, Disease stage, Treatment, Subject
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Canonical and atypical E2Fs regulate the mammalian endocycle.
Age, Specimen part
View Samples