We performed gene expression profiling of total RNA from brain samples derived from BSE-infected versus non-infected cynomolgus macaques (Macaca fascicularis).
Gene expression profiling of brains from bovine spongiform encephalopathy (BSE)-infected cynomolgus macaques.
Sex, Age, Specimen part
View SamplesPseudomonas aeruginosa is an opportunistic pathogen that can adapt to changing environments and can secrete an exopolysaccharide known as alginate as a protection response resulting in a colony morphology and phenotype referred to as mucoid. However how P. aeruginosa senses its environment and activates alginate overproduction is not fully understood. Previously, we showed that Pseudomonas isolation agar (PIA) supplemented with ammonium metavanadate (PIAAMV) induces P. aeruginosa to overproduce alginate. Vanadate is a phosphate mimic and causes protein misfolding by disruption of disulfide bonds. Here we used PIAAMV to characterize the pathways involved in inducible alginate production and tested the global effects of P. aeruginosa growth on PIAAMV by a mutant library screen, transcriptomics, and in a murine acute virulence model. The PA14 non-redundant mutant library was screened on PIAAMV to identify new genes that are required for the inducible alginate stress response. A functionally diverse set of genes encoding products involved in cell envelope biogenesis, peptidoglycan, uptake of phosphate and iron, phenazines biosynthesis, and other processes were identified as positive regulators of the mucoid phenotype on PIAAMV. Transcriptome analysis of P. aeruginosa growing in the presence of vanadate caused differential expression of genes involved in virulence, envelope biogenesis, and cell stress pathways. In this study, it was observed that growth on PIAAMV attenuates P. aeruginosa in a mouse pneumonia model. Induction of alginate overproduction occurs as a stress response to protect P. aeruginosa but it may be possible to modulate and inhibit these pathways based on the new genes identified in this study.
Genes required for and effects of alginate overproduction induced by growth of Pseudomonas aeruginosa on Pseudomonas isolation agar supplemented with ammonium metavanadate.
No sample metadata fields
View SamplesThe molecular events at the basis of prion diseases are characterized by the involvement of several genes which are differentially regulated during the onset and the progression of the infection. Gene expression profiling studies are a powerful tool for the development of preclinical diagnostic tests. Most of the studies performed up to date utilized tissues which are not suitable for a future perspective of a rapid analysis of the infected animals and patients.
Whole Blood Gene Expression Profiling in Preclinical and Clinical Cattle Infected with Atypical Bovine Spongiform Encephalopathy.
Sex, Specimen part
View SamplesThe Pseudomonas aeruginosa response regulator AlgR is critical for the organism's virulence and controls up to 155 different genes. In order to determine which genes are controlled by phosphorylated and unphosphorylated AlgR, phosphomimetic and phosphoablative alleles were recombined onto the chromosome of PAO1. The algR gene was mutated at aspartate 54 to asparagine (D54N) for the phosphoablative allele and mutated at aspartete 54 to glutamate (D54E) for the phosphomimetic allele. These alleles were recombined into the PAO1 chromosome.
<i>Pseudomonas aeruginosa</i> AlgR Phosphorylation Status Differentially Regulates Pyocyanin and Pyoverdine Production.
No sample metadata fields
View SamplesAnalysis of hepatic gene expression in mice transiently overexpressing Bcl2 Overall design: 3 control GFP mice and 5 GFP-Bcl2 mice, 8 mouse liver samples total
Bcl2 is a critical regulator of bile acid homeostasis by dictating Shp and lncRNA H19 function.
No sample metadata fields
View SamplesPre-mRNA splicing is functionally coupled to transcription, and genotoxic stresses can enhance alternative exon inclusion by affecting elongating RNA polymerase II. We report here that various genotoxic stress inducers, including camptothecin, inhibit the interaction between EWS, an RNA polymerase II-associated factor, and YB-1, a spliceosome-associated factor. This results in the cotranscriptional skipping of several exons of the MDM2 gene encoding the main p53 ubiquitin-ligase. This reversible exon skipping participates in the timely regulation of MDM2 expression, and may contribute to the accumulation of p53 during stress exposure and its rapid shut off when stress is removed. Finally, a splicing-sensitive microarray identified numerous exons that are skipped in response to camptothecin and EWS/YB-1 depletion. These data demonstrate genotoxic stress-induced alteration of the communication between the transcriptional and splicing machineries, resulting in widespread exon skipping and playing a central role in the genotoxic stress response.
Cotranscriptional exon skipping in the genotoxic stress response.
Specimen part, Cell line
View SamplesThe transcription factor STAT3 is constitutively activated in tumors of different origin but the molecular bases for STAT3 addiction of tumor cells have not yet been clearly identified. We generated knock/in mice carrying the constitutively active Stat3 allele, Stat3C, and showed that Stat3C could enhance Neu oncogenic power, triggering the production of earlier onset, more invasive mammary tumors. Tumor-derived cell lines displayed higher migration and invasion and disrupted distribution of cell-cell junction markers. The tensin family member Cten (C-Terminal Tensin-like), known to mediate EGF-induced migration and highly expressed in inflammatory breast cancer, was up-regulated in both Neu;Stat3C cells and tumors. Both Cten expression and enhanced migration were strictly dependent on Stat3, and Cten silencing normalized cell migration and rescued cell-cell contact defects. Importantly, the pro-inflammatory cytokine IL-6 could mediate Cten induction in MCF10 cells, in an exquisitely Stat3-dependent way. This model allowed us to shed some light on the oncogenic role of Stat3 in the breast, suggesting moreover a mechanism through which inflammatory signals can cooperate with EGF receptors in inflammatory breast cancer.
Constitutively active Stat3 enhances neu-mediated migration and metastasis in mammary tumors via upregulation of Cten.
No sample metadata fields
View SamplesThe fruit fly Drosophila melanogaster is a good model to unravel the molecular mechanisms of innate immunity, and has led to some important discoveries on the sensing and signalling of microbial infections. The response of drosophila to virus infections remains poorly characterized, and appears to involve two facets. On one hand RNA interference (RNAi) involves the recognition and processing of dsRNA into small interfering (si) RNAs by the host ribonuclease Dicer-2 (Dcr-2), whereas on the other hand an inducible response controlled by the evolutionarily conserved JAK/STAT pathway contributes to the antiviral host defence. In order to clarify the contribution of the siRNA and JAK/STAT pathways to the control of viral infections, we have compared the resistance of flies wild-type or mutant for Dcr-2 or the JAK kinase Hopscotch (Hop) to infections by seven RNA or DNA viruses belonging to different families. Our results reveal a unique susceptibility of hop mutant flies to infection by DCV and CrPV, two members of the Dicistroviridae family. Genome-wide microarray analysis confirmed that different sets of genes were induced following infection by DCV (GSE2828) or two unrelated RNA viruses, FHV and SINV. Overall, our data reveal that RNAi is an efficient antiviral mechanism, operating against a large range of viruses, including a DNA virus. By contrast, the antiviral contribution of the JAK/STAT pathway appears to be virus-specific.
Broad RNA interference-mediated antiviral immunity and virus-specific inducible responses in Drosophila.
Time
View SamplesWe used an inducible ShRNA system and microarrays to detail the global programme of gene expression underlying neuroblastoma differentiation upon CHAF1A silencing .
Histone chaperone CHAF1A inhibits differentiation and promotes aggressive neuroblastoma.
No sample metadata fields
View Samplesaffy_ccr_maize - affy_ccr_maize - Cinnamoyl-CoA reductase (CCR) catalyzes a key step in monolignol biosynthesis. We show that downregulation of CCR in maize was associated with lower lignin content and a strong decrease in H units. Concomitantly, these cell wall modifications were associated with higher digestibility. On another hand, immunocytochemistry indicated a modification of lignification pattern and cellulose content. Transcript profiling was used as comprehensive phenotyping tools to investigate how CCR downregulation impacted metabolism and the biosynthesis of other cell wall polymers. -2 wild type and 2 CCR mutants were compared. Plants were grown in greenhouse condition and harvested at 7-8 leaf stages.
Characterization of a cinnamoyl-CoA reductase 1 (CCR1) mutant in maize: effects on lignification, fibre development, and global gene expression.
No sample metadata fields
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