Ischemic tolerance can be induced by numerous preconditioning stimuli, including various Toll-like receptor (TLR) ligands. We have shown previously that systemic administration of the TLR4 ligand, lipopolysaccharide (LPS) or the TLR9 ligand, unmethylated CpG ODNs prior to transient brain ischemia in mice confers substantial protection against ischemic damage. To elucidate the molecular mechanisms of preconditioning, we compared brain and blood genomic profiles in response to preconditioning with these TLR ligands and to preconditioning via exposure to brief ischemia.
Multiple preconditioning paradigms converge on interferon regulatory factor-dependent signaling to promote tolerance to ischemic brain injury.
Specimen part, Treatment
View SamplesC57BL/6J (B6) and DBA/2J (D2) are two of the most commonly used inbred mouse strains in neuroscience research. However, the only currently available mouse genome is based entirely on the B6 strain sequence. Subsequently, oligonucleotide microarray probes are based solely on this B6 reference sequence, making their application for gene expression profiling comparisons across mouse strains dubious due to their allelic sequence differences, including single nucleotide polymorphisms (SNPs). The emergence of next-generation sequencing (NGS) and the RNA-Seq application provides a clear alternative to oligonucleotide arrays for detecting differential gene expression without the problems inherent to hybridization-based technologies. Using RNA-Seq, an average of 22 million short sequencing reads were generated per sample for 21 samples (10 B6 and 11 D2), and these reads were aligned to the mouse reference genome, allowing 16,183 Ensembl genes to be queried in striatum for both strains. To determine differential expression, 'digital mRNA counting' is applied based on reads that map to exons. The current study compares RNA-Seq (Illumina GA IIx) with two microarray platforms (Illumina MouseRef-8 v2.0 and Affymetrix MOE 430 2.0) to detect differential striatal gene expression between the B6 and D2 inbred mouse strains. We show that by using stringent data processing requirements differential expression as determined by RNA-Seq is concordant with both the Affymetrix and Illumina platforms in more instances than it is concordant with only a single platform, and that instances of discordance with respect to direction of fold change were rare. Finally, we show that additional information is gained from RNA-Seq compared to hybridization-based techniques as RNA-Seq detects more genes than either microarray platform. The majority of genes differentially expressed in RNA-Seq were only detected as present in RNA-Seq, which is important for studies with smaller effect sizes where the sensitivity of hybridization-based techniques could bias interpretation.
No associated publication
Sex, Specimen part
View SamplesWe used gene expression microarrays to identify genes whose expression was influenced differently by TNFa in Fancc-deficient mice compared to wild type (WT) mice. To identify genes whose expression was directly or indirectly influenced by Fancc, we looked in particular for genes either suppressed or induced by TNF in WT cells that were not affected by TNF in Fancc-deficient cells.
FANCL ubiquitinates β-catenin and enhances its nuclear function.
Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Otitis media impacts hundreds of mouse middle and inner ear genes.
Age, Specimen part, Treatment
View SamplesObjective: Otitis media is known to alter expression of cytokine and other genes in the mouse middle ear and inner ear. However, whole mouse genome studies of gene expression in otitis media have not previously been undertaken. Ninety-nine percent of mouse genes are shared in the human, so these studies are relevant to the human condition.
Otitis media impacts hundreds of mouse middle and inner ear genes.
Age, Specimen part, Treatment
View SamplesObjective: Otitis media is known to alter expression of cytokine and other genes in the mouse middle ear and inner ear. However, whole mouse genome studies of gene expression in otitis media have not previously been undertaken. Ninety-nine percent of mouse genes are shared in the human, so these studies are relevant to the human condition.
Otitis media impacts hundreds of mouse middle and inner ear genes.
Age, Specimen part, Treatment
View SamplesTo identify the molecular impact of SPIO nanoparticle inhalation exposure on lung tissue.
No associated publication
Sex, Specimen part, Treatment
View SamplesMethyl tert-butyl ether (MTBE) has been shown to target developing vasculature in piscine and mammalian model systems. In the zebrafish, MTBE induces vascular lesions throughout development. These lesions result from exposure to MTBE at an early stage in development (6-somites to Prim-5 stages). During this time period, transcript levels of vegfa, vegfc, and vegfr1 were significantly decreased in embryos exposed to 5 mM MTBE.
Manipulation of the HIF-Vegf pathway rescues methyl tert-butyl ether (MTBE)-induced vascular lesions.
Specimen part
View SamplesZebrafish have the remarkable ability to regenerate body parts including the heart, spinal cord and fins by a process referred to as epimorphic regeneration. Recent studies have illustrated that similar to adult zebrafish, early life stage-larvae also possess the ability to regenerate the caudal fin. A comparative genomic analysis was used to determine the degree of conservation in gene expression among the regenerating adult caudal fin, adult heart and larval fin. Results indicate that these tissues respond to amputation/injury with strikingly similar genomic responses. Comparative analysis revealed raldh2, a rate-limiting enzyme for the synthesis of Retinoic acid (RA), as one of the highly induced genes across the three regeneration platforms.
Comparative expression profiling reveals an essential role for raldh2 in epimorphic regeneration.
No sample metadata fields
View SamplesAtherosclerosis is a chronic inflammatory disease characterized by the accumulation of lipid-loaded macrophages in the arterial wall. Intimal macrophages internalize modified lipoproteins such as oxidized LDL (oxLDL) through scavenger receptors, leading to storage of excess cholesteryl esters in lipid bodies and a "foam cell" phenotype. In addition, stimulation of macrophage Toll-like receptors (TLRs) has been shown to promote lipid body proliferation. We investigated the possibility that there are transcriptional regulators that are common to both pathways for stimulating foam cell formation (modified lipoproteins and TLR stimulation), and identified the transcription factor ATF3 as a candidate regulator.
ATF3 protects against atherosclerosis by suppressing 25-hydroxycholesterol-induced lipid body formation.
Sex, Specimen part
View Samples