Several bacterial human pathogens regulate the production of virulence factors by temperature, expressing them only at 37 C. Accordingly we show that the production of all P. aeruginosa virulence factors that are dependent on the QS transcriptional regulator RhlR, but only a fraction that are activated by LasR, are induced at 37 C compared to 30 C or 25 C. The RhlR-dependent induction at 37 C is a posttranscriptional effect due to an RNA thermometer of the ROSE family that thermoregulates the expression of rhlAB operon involved in rhamnolipids production, a virulence associated trait. This RNA structure also affects the expression of the downstream rhlR gene. A second thermometer is present upstream lasI and causes a reduced expression of this gene at lower temperatures without causing a significant decrease of the autoinducer 3-oxo-dodecanoyl homoserine lactone.
Regulation of Pseudomonas aeruginosa virulence factors by two novel RNA thermometers.
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View SamplesBackground. Although the emergence of RNA sequencing (RNA-seq), microarrays remain in widespread use for gene expression analysis in the clinic. There are over 767,000 RNA microarrays from human samples in public repositories, which are an invaluable resource for biomedical research and personalized medicine. The absolute gene expression analysis allows the transcriptome profiling of all expressed genes under the specific biological condition without the need of a reference sample. However, the background fluorescence represents a challenge to determine the absolute gene expression in microarrays. Given that the Y chromosome is absent in female subjects, we used it as a new approach for absolute gene expression analysis in which the fluorescence of the Y chromosome genes of female subjects was used as the background fluorescence for all the probes in the microarray. This fluorescence was used to establish an absolute gene expression threshold, allowing the differentiation between expressed and non-expressed genes in microarrays.
A novel approach for human whole transcriptome analysis based on absolute gene expression of microarray data.
Sex, Specimen part
View SamplesPhysical performance relies on the concerted action of myriad responses, many of which are under circadian clock control. Little is known, however, regarding the time-dependent effect on exercise performance at the molecular level. We found that both mice and humans exhibit day-time variance in exercise capacity between the early and late part of their active phase. The day-time variance in mice was dependent on exercise intensity and relied on the circadian clock proteins PER1/2. High throughput gene expression and metabolic profiling of skeletal muscle revealed metabolic pathways that are differently activated upon exercise in a day-time dependent manner. Remarkably, we discovered that ZMP, an endogenous AMPK activator, is induced by exercise in a time-dependent manner to regulate key steps in glycolytic and fatty acid oxidation pathways and potentially enhance exercise capacity. Overall, we propose that time of the day is a major modifier of exercise capacity and associated metabolic pathways. Overall design: basal, high intensity and moderate intensity runnig protocol at ZT14 and ZT22 in gastrocnemius muscle in C57B6 mice
Physiological and Molecular Dissection of Daily Variance in Exercise Capacity.
Sex, Cell line, Subject, Time
View SamplesIn pluripotential reprogramming, a pluripotent state is established within somatic cells. In this study, we have generated induced pluripotent stem (iPS) cells from bi-maternal (uniparental) parthenogenetic neural stem cells (pNSCs) by transduction with four (Oct4, Klf4, Sox2, and c-Myc) or two (Oct4 and Klf4) transcription factors. The parthenogenetic iPS (piPS) cells directly reprogrammed from pNSCs were able to generate germline-competent himeras, and hierarchical clustering analysis showed that piPS cells were clustered more closer to parthenogenetic ES cells than normal female ES cells. Interestingly, piPS cells showed loss of parthenogenetic-specific imprinting patterns of donor cells. Microarray data also showed that the maternally imprinted genes, which were not expressed in pNSCs, were upregulated in piPS cells, indicating that pluripotential reprogramming lead to induce loss of imprinting as well as re-establishment of various features of pluripotent cells in parthenogenetic somatic cells.
Generation of parthenogenetic induced pluripotent stem cells from parthenogenetic neural stem cells.
Sex, Specimen part
View SamplesPurpose: The phosphoinositide 3-kinase (PI3K) pathway is fundamental for cell proliferation and survival and is frequently altered and activated in neoplasia, including carcinomas of the lung. In this study we investigated the potential of targeting the catalytic class IA PI3K isoforms in small cell lung cancer (SCLC), which is the most aggressive of all lung cancer types. Experimental Design: The expression of PI3K isoforms in patient specimens was analyzed. The effects on SCLC cell survival and downstream signaling were determined following PI3K isoform inhibition by selective inhibitors or down-regulation by small interfering RNA. Results: Over-expression of the PI3K isoforms p110 and p110 was shown by immunohistochemistry in primary SCLC tissue samples. Targeting the PI3K p110 with RNA interference (RNAi) or selective pharmacological inhibitors resulted in strongly affected cell proliferation of SCLC cells in vitro and in vivo, while targeting p110 was less effective. Inhibition of p110 also resulted in increased apoptosis and autophagy, which was accompanied by decreased phosphorylation of Akt and components of the mammalian target of rapamycin (mTOR) pathway, such as the ribosomal S6 protein, and the eukaryotic translation initiation factor 4E-binding protein 1 (4E-BP1). A DNA microarray analysis revealed that p110 inhibition profoundly affected the balance of pro- and anti-apoptotic Bcl-2 family proteins. Finally, p110 inhibition led to impaired SCLC tumor formation and vascularization in vivo. Conclusion: Together our data demonstrate the key involvement of the PI3K isoform p110 in multiple tumor-promoting processes in SCLC.
Targeting the phosphoinositide 3-kinase p110-α isoform impairs cell proliferation, survival, and tumor growth in small cell lung cancer.
Cell line, Treatment
View SamplesTGF-beta3 produced by developing Th17 cells induces highly pathogenic T cells that are functionally and molecularly distinct from TGF-beta1-induced Th17 cells. The microarray data represent a distinct molecular signature for pathogenic versus non-pathogenic Th17 cells.
Induction and molecular signature of pathogenic TH17 cells.
Sex, Specimen part
View SamplesThis study is a follow-up to GSE35790.
Transcriptional regulatory logic of the diurnal cycle in the mouse liver.
Sex, Specimen part, Time
View SamplesGene transcripts and proteins expressed during disease pathogenesis identify targets for therapy. We performed microarray analysis of histologically characterized multiple sclerosis (MS) brain lesions in comparison with control brain samples to identify differentially expressed molecules. We identified CD47 as a target of interest and studied its biology in MS and EAE.
Janus-like opposing roles of CD47 in autoimmune brain inflammation in humans and mice.
Specimen part, Disease, Disease stage
View SamplesLiver RNA samples from C57BL6 mice drinking Hydrogen water for 4 weeks
Molecular hydrogen upregulates heat shock response and collagen biosynthesis, and downregulates cell cycles: meta-analyses of gene expression profiles.
Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
A unique H2A histone variant occupies the transcriptional start site of active genes.
Sex, Age, Specimen part
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