Glucocorticoids play central roles in the regulation of energy metabolism by shifting it toward catabolism, while AMPK is the master regulator of energy homeostasis, sensing energy depletion and stimulating pathways of increasing fuel uptake and saving on peripheral supplies. We showed here that AMPK regulates glucocorticoid actions on carbohydrate metabolism by targeting the glucocorticoid receptor (GR) and modifying transcription of glucocorticoid-responsive genes in a tissue- and promoter-specific fashion. Activation of AMPK in rats reversed glucocorticoid-induced hepatic steatosis and suppressed glucocorticoid-mediated stimulation of glucose metabolism. Transcriptomic analysis in the liver suggested marked overlaps between the AMPK and glucocorticoid signaling pathways directed mostly from AMPK to glucocorticoid actions. AMPK accomplishes this by phosphorylating serine 211 of the human GR indirectly through phosphorylation and consequent activation of p38 MAPK and by altering attraction of transcriptional coregulators to DNA-bound GR. In human peripheral mononuclear cells, AMPK mRNA expression positively correlated with that of glucocorticoid-responsive GILZ, which correlated also positively with the body mass index of subjects. These results indicate that the AMPK-mediated energy control system modulates glucocorticoid action at target tissues. Since increased action of glucocorticoids is associated with development of metabolic disorders, activation of AMPK could be a promising target for developing pharmacologic interventions to these pathologies.
AMPK regulates metabolic actions of glucocorticoids by phosphorylating the glucocorticoid receptor through p38 MAPK.
Sex
View SamplesSecond-hand smoke (SHS) exposure during pregnancy has adverse effects on offspring. We used microarrays to characterize the gene expression changes caused by in-utero exposure and adult exposure to SHS in adult mouse lungs.
In utero exposure to second-hand smoke aggravates adult responses to irritants: adult second-hand smoke.
Sex, Age, Specimen part, Treatment
View SamplesSHS exposure during pregnancy has adverse effects on offspring.
In utero exposure to second-hand smoke aggravates the response to ovalbumin in adult mice.
Sex, Specimen part
View SamplesProtein synthesis belongs to the most energy consuming processes in the cell. Lowering oxygen tension below normal (hypoxia) causes a rapid inhibition of global mRNA translation due to the decreased availability of energy. Interestingly, subsets of mRNAs pursue active translation under such circumstances. In human fibrosarcoma cells (HT1080) exposed to prolonged hypoxia (36 h, 1% oxygen) we observed that transcripts are either increasingly or decreasingly associated with ribosomes localized at the endoplasmic reticulum (ER). In a global setting it turned out that only 31% of transcripts showing elevated total-RNA levels were also increasingly present at the ER in hypoxia. These genes, regulated by its expression as well as its ER-localization, belong to the gene ontologys hypoxia response, glycolysis and HIF-1 transcription factor network supporting the view of active mRNA translation at the ER during hypoxia. Interestingly, a large group of RNAs was found to be unchanged at the expression level, but translocate to the ER in hypoxia. Among these are transcripts encoding translation factors and >180 ncRNAs. In summary, we provide evidence that protein synthesis is favoured at the ER and, thus, partitioning of the transcriptome between cytoplasmic and ER associated ribosomes mediates adaptation of gene expression in hypoxia.
Hypoxia-induced gene expression results from selective mRNA partitioning to the endoplasmic reticulum.
Specimen part, Cell line
View SamplesLiving organisms have to cope with multiple and combined fluctuations in their environment. According to their sessile mode of life, plants are even more subjected to such fluctuations impacting their physiology and development. In particular, nutrient availability is known to tune plant development through modulating hormonal signaling, and conversely, hormonal signals are key to control nutrient related signaling pathways (Krouk et al., 2011a). However, very few is known about molecular mechanisms leading to plant adaptation to such combined signals. Here we deployed an unprecedented combinatorial treatment matrix to reveal plant adaptation in response to nitrate (NO3-), ammonium (NH4+), auxin (IAA), cytokinins (CK) and abscisic acid (ABA) and their exhaustive binary combinations.
Combinatorial interaction network of transcriptomic and phenotypic responses to nitrogen and hormones in the Arabidopsis thaliana root.
Specimen part, Time
View SamplesWe used microarray analysis to investigate if keratinocytes excert an immuno-inflammatory response towards streptococcal M1 protein.
Vigilant keratinocytes trigger pathogen-associated molecular pattern signaling in response to streptococcal M1 protein.
Specimen part, Cell line
View SamplesA significant proportion of differentially expressed genes were associated with extracellular matrix organization and extracellular structure organization.
LAMA4 upregulation is associated with high liver metastasis potential and poor survival outcome of Pancreatic Cancer.
Specimen part, Treatment
View SamplesWe used the flu mutant of Arabidopsis and a transgenic line that overexpresses the thylakoid-bound ascorbate peroxidase (tAPX) to address the interactions between different reactive oxygen species (ROS) signaling pathways. The conditional flu mutant of Arabidopsis accumulates excess protochlorophyllide in the dark within chloroplast membranes that upon illumination acts as a photosensitizer and generates singlet oxygen (1O2). Immediately after the release of singlet oxygen rapid changes in nuclear gene expression occur. Distinct sets of genes were activated that were different from those induced by other reactive oxygen species, superoxide or hydrogen peroxide (H2O2), suggesting that different types of active oxygen species activate distinct signaling pathways. It was not known whether the pathways operate separately or interact with each other. We have addressed this problem by modulating noninvasively the level of H2O2 in plastids by means of a transgenic line that overexpresses the thylakoid-bound ascorbate peroxidase (tAPX, line 14/2 PMID: 15165186). In the flu mutant overexpressing tAPX, the expression of most of the nuclear genes that were rapidly activated after the release of 1O2 was significantly higher in flu plants overexpressing tAPX, whereas in wild-type plants, overexpression of tAPX had only a very minor impact on nuclear gene expression. The results suggest that H2O2 antagonizes the 1O2-mediated signaling of stress responses as seen in the flu mutant. This cross-talk between H2O2- and 1O2-dependent signaling pathways might contribute to the overall stability and robustness of wild-type plants exposed to adverse environmental stress conditions.
Cross-talk between singlet oxygen- and hydrogen peroxide-dependent signaling of stress responses in Arabidopsis thaliana.
No sample metadata fields
View SamplesClimate change and disease have large negative impacts on poultry production, but little is known about the interactions of responses to these stressors in chickens. Fayoumi (heat and disease resistant) and broiler (heat and disease susceptible) chicken lines were stimulated at 22 days of age, using a 2x2x2 factorial design including: breed (Fayoumi or broiler), inflammatory stimulus [lipopolysaccharide (LPS) or saline], and temperature (35°C or 25°C). Transcriptional changes in spleens were analyzed using RNA-sequencing on the Illumina HiSeq 2500. Thirty-two individual cDNA libraries were sequenced (four per treatment) and an average of 22 million reads were generated per library. Stimulation with LPS induced more differentially expressed genes (DEG, log2 fold change = 2 and FDR = 0.05) in the broiler (N=283) than the Fayoumi (N=85), whereas heat treatment resulted in fewer DEG in broiler (N=22) compared to Fayoumi (N=107). The double stimulus of LPS+heat induced the largest numbers of changes in gene expression, for which broiler had 567 DEG and Fayoumi had 1471 DEG of which 399 were shared between breeds. Further analysis of DEG revealed pathways impacted by these stressors such as Remodelling of Epithelial Adherens Junctions due to heat stress, Granulocyte Adhesion and Diapedesis due to LPS, and Hepatic Fibrosis/Hepatic Stellate Cell Activation due to LPS+heat. The genes and pathways identified provide deeper understanding of the response to the applied stressors and may serve as biomarkers for genetic selection for heat and disease tolerant chickens. Overall design: At 22 days of age, divergent chicken breeds (Fayoumi and broiler) were treated with a thermal treatment (heat stress at 35C, or thermoneutral at 25C as a control) for 3.5 hours, then stimulated subcutaneously with an inflammatory stimulus (LPS, or saline as a control) for another 3.5 hours. Chickens were euthanized and spleens were harvested. A total of 32 indivudally coded cDNA libraries were prepared using TruSeq v2 library preparation kit which selects for polyA mRNA. In this 2x2x2 full factorial design with the factors of breed, thermal treatment, and inflammatory stimulus, there were a total of 8 treatment groups. Each treatment group had a total of 4 animal biological replicates. Therefore, a total of 32 individual barcoded samples were sequenced. A total of 8 individually barcoded cDNA libraries were sequenced per lane using the HiSeq Illumina 2500, and we used 4 lanes total. Reads were mapped to Galgal 2.0.
Unique genetic responses revealed in RNA-seq of the spleen of chickens stimulated with lipopolysaccharide and short-term heat.
Subject
View SamplesSle1c is a sublocus of the NZM2410-derived Sle1 major susceptibility locus. We have previously shown that Sle1c contributes to lupus pathogenesis by conferring CD4+ T cell-intrinsic hyperactivation and increased susceptibility to chronic graft-versus-host disease (cGVHD) that mapped to the centromeric portion of the locus. In this study, we have refined the centromeric sublocus to a 675Kb interval, termed Sle1c2. Recombinant congenic strains expressing Sle1c2 exhibited a T cell-intrinsic CD4+ T cell hyperactivation and cGVHD susceptibility, similar to mice with the parental Sle1c.
Murine lupus susceptibility locus Sle1c2 mediates CD4+ T cell activation and maps to estrogen-related receptor γ.
Sex, Age, Specimen part
View Samples