Background: Mycobacterium avium subspecies paratuberculosis (MPTb) is the causative agent of Johnes disease, an intestinal disease of ruminants with major economic consequences. MPTb bacilli are phagocytosed by host macrophages upon exposure where they persist, resulting in lengthy subclinical phases of infection that can lead to immunopathology and disease dissemination. Consequently, analysis of the macrophage transcriptome in response to MPTb infection can provide valuable insights into the molecular mechanisms that underlie Johnes disease. Here, we investigate pan-genomic gene expression in bovine monocyte-derived macrophages (MDM) purified from seven age-matched non-related females, in response to in vitro infection with MPTb (multiplicity of infection 2:1) at intervals of 2 hours, 6 hours and 24 hours post-infection.
Pan-genomic analysis of bovine monocyte-derived macrophage gene expression in response to in vitro infection with Mycobacterium avium subspecies paratuberculosis.
Sex, Age, Specimen part, Time
View SamplesMycobacterium bovis is an intracellular pathogen that causes tuberculosis in cattle. Following infection, the pathogen resides and persists inside host macrophages by subverting host immune responses via a diverse range of mechanisms. Here, a high-density bovine microarray platform was used to examine the bovine monocyte-derived macrophage transcriptome response to M. bovis infection relative to infection with the attenuated vaccine strain, M. bovis Bacille CalmetteGurin. Differentially expressed genes were identified (adjusted P-value 0.01) and interaction networks generated across an infection time course of 2, 6 and 24 h. The largest number of biological interactions was observed in the 24 h network, which exhibited small-worldscale-free network properties. The 24 h network featured a small number of key hub and bottleneck gene nodes, including IKBKE, MYC, NFKB1 and EGR1 that differentiated the macrophage response to virulent and attenuated M. bovis strains, possibly via the modulation of host cell death mechanisms. These hub and bottleneck genes represent possible targets for immunomodulation of host macrophages by virulent mycobacterial species that enable their survival within a hostile environment.
Key Hub and Bottleneck Genes Differentiate the Macrophage Response to Virulent and Attenuated Mycobacterium bovis.
Sex, Age, Specimen part, Treatment, Time
View SamplesBackground: Mycobacterium bovis, the causative agent of bovine tuberculosis, is a major cause of mortality in global cattle populations. Macrophages are among the first cells types to encounter M. bovis following exposure and the response elicited by these cells is pivotal in determining the outcome of infection. Here, a functional genomics approach was undertaken to investigate global gene expression profiles in bovine monocyte-derived macrophages (MDM) purified from seven age-matched non-related females, in response to in vitro challenge with M. bovis (multiplicity of infection 2:1). Total cellular RNA was extracted from non-challenged control and M. bovis-challenged MDM for all animals at intervals of 2 hours, 6 hours and 24 hours post-challenge and prepared for global gene expression analysis using the Affymetrix GeneChip Bovine Genome Array.
Global gene expression and systems biology analysis of bovine monocyte-derived macrophages in response to in vitro challenge with Mycobacterium bovis.
Sex, Age, Specimen part, Time
View SamplesThe aim of the study was to illucidate how BAFF mediates B cell survival and growth through the identification of BAFF-regulated genes.
BAFF controls B cell metabolic fitness through a PKC beta- and Akt-dependent mechanism.
No sample metadata fields
View SamplesCytochrome oxydases and quinol monooxygenase were removed from the E. coli genome resulting in oxygen-independent physiology
Deletion of genes encoding cytochrome oxidases and quinol monooxygenase blocks the aerobic-anaerobic shift in Escherichia coli K-12 MG1655.
No sample metadata fields
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Alteration of mRNA and microRNA expression profiles in rat muscular type vasculature in early postnatal development.
Sex
View SamplesAdult-onset diseases can be associated with in utero events, but mechanisms for such temporally distant dysregulation of organ function remain unknown. The polycomb histone methyltransferase, Ezh2, stabilizes transcription by depositing repressive histone marks during development that persist into adulthood, but the function of Ezh2-mediated transcriptional stability in postnatal organ homeostasis is not understood. Here, we show that Ezh2 stabilizes the postnatal cardiac gene expression program and prevents cardiac pathology, primarily by repressing the homeodomain transcription factor Six1 in differentiating cardiac progenitors. Loss of Ezh2 in embryonic cardiac progenitors, but not in differentiated cardiomyocytes, resulted in postnatal cardiac pathology, including cardiomyocyte hypertrophy and fibrosis. Loss of Ezh2 caused broad derepression of skeletal muscle genes, including the homeodomain transcription factor Six1, which is expressed in cardiac progenitors but is normally silenced upon cardiac differentiation. Many of the deregulated genes are direct Six1 targets, implying a critical requirement for stable repression of Six1 in cardiac myocytes. Indeed, upon de-repression, Six1 promotes cardiac pathology, as it was sufficient to induce cardiac hypertrophy. Furthermore, genetic reduction of Six1 levels almost completely rescued the pathology of Ezh2-deficient hearts. Thus, repression of a single transcription factor in cardiac progenitors by Ezh2 is essential for stability of the adult heart gene expression program and homeostasis. Our results suggest that epigenetic dysregulation during discrete developmental windows can predispose to adult disease and dysregulated stress responses.
Epigenetic repression of cardiac progenitor gene expression by Ezh2 is required for postnatal cardiac homeostasis.
Specimen part
View SamplesThis study tested the hypothesis that mRNA expression profiles change in the muscular type rat saphenous artery during early postnatal development. To explore this, we performed mRNA microarray analysis on muscular type saphenous arteries of young (10-12 days) and adult (2-3 months) rats.
Alteration of mRNA and microRNA expression profiles in rat muscular type vasculature in early postnatal development.
Sex
View SamplesAlthough in vitro studies of embryonic stem cells have identified Polycomb repressor complexes (PRCs) as key regulators of differentiation, it remains unclear as to how PRC-mediated mechanisms control fates of multipotent progenitors in developing tissues. Here, we show that an essential PRC component, Ezh2, is expressed in epidermal progenitors, but diminishes concomitant with embryonic differentiation and with postnatal decline in proliferative activity. We show that Ezh2 controls proliferative potential of basal progenitors by repressing the Ink4A-Ink4B locus, and tempers the developmental rate of differentiation by preventing premature recruitment of AP1 transcriptional activator to the structural genes that are required for epidermal differentiation. Together, our studies reveal that PRCs control epigenetic modifications temporally and spatially in tissue-restricted stem cells by maintaining their proliferative potential and globally repressing undesirable differentiation programs, while selectively establishing a specific terminal differentiation program in a step-wise fashion.
Ezh2 orchestrates gene expression for the stepwise differentiation of tissue-specific stem cells.
No sample metadata fields
View SamplesGoal of the experiment: Analysis of gene expression changes in the cortex, striatum, hippocampus, hypothalamus, Drd2-MSNs and Drd1-MSNs of mice with a postnatal, neuron-specific ablation of GLP or G9a as compared to control mice.
Control of cognition and adaptive behavior by the GLP/G9a epigenetic suppressor complex.
Specimen part
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