Purpose: Investigating the role of Drosophila G9a in oxidative stress responses. Methods: Flies were collected after eclosion and allowed to recover from CO2 exposure for 5 days prior to paraquat exposure. Paraquat (Methyl viologen dichloride hydrate 98 %; Sigma 856177) was mixed into the flyfood at 40 °C to a final concentration of 50 mM. For OS induction, 5-9 day old flies were transferred to paraquat containing food and incubated at 25 °C and 70 % humidity. At each time point, flies were flash frozen in liquid nitrogen followed by vortexing and filtering through a series of sieves to isolate heads from other body parts. 200 fly heads per sample were used for RNA extraction using QIAGEN lipid mini tissue kit. The TruSeq RNA Sample Preparation Kit v2 (Illumina) was used to prepare adapter ligated PCR fragments for sequencing. PCR was used to selectively enrich the fragments containing the adapters. The PCR fragments were validated using Agilent 2200 TapeStation. Single indexed samples were multiplexed and sequenced on an Illumina HiSeq 2000 sequencing system (Illumina) in single-end mode with a read length of 35 bp. Quality of sequenced reads was assessed with FastQC. The RNAseq experiments were conducted on two biological duplicates for each condition. Sequenced reads were aligned with Burrows-Wheeler algorithm (BWA) (Li & Durbin, 2010) to the Drosophila reference genome (BDGP.5, http://www.fruitfly.org/) and per gene read counts were generated with HTSeq count (Anders et al, 2015). 25–30 million reads with high quality alignment were obtained for each sample and used for differential expression analysis. DESeq (Anders & Huber, 2010) was used to obtain library size-normalized read counts and to calculate differential expression of genes in 4 pairwise comparisons: 0 h versus 6 h and 0 h versus 12 h after OS in both G9a mutants and controls (fold change =1.5, adjusted p-value= 0.05, Benjamini-Hochberg). Results: We found 2731 genes to be differential expressed in at least one of the four pairwise comparisons. The largest group of differentially expressed (DE) genes are highly augmented upon OS induction in the G9a mutant (41.7 % of all DE genes). The second largest group of DE genes (23.9 % of all DE genes) were more downregulated in G9a mutant in response to OS. Genes that are over-activated in G9a mutants are predominantly involved in OS response and OS mediated damage, whereas genes that are downregulated in G9a mutants are involved in energy metabolism. Conclusions: Our data suggest that G9a provides an epigenetic mechanism that safeguards an appropriate transcriptional response to OS and preserves immediately available energy, thereby acting as a critical regulatory hub between the transcriptional and physiological responses to oxidative stress. Overall design: fly-head mRNA libraries of 5-9 days old male G9aDD1 mutant and control during 0, 6 and 12 hours of paraquat oxidative stress exposure were sequenced in duplicate on Hi-seq 2000.
The histone methyltransferase G9a regulates tolerance to oxidative stress-induced energy consumption.
Specimen part, Treatment, Subject
View SamplesObjective
A subset of metastatic pancreatic ductal adenocarcinomas depends quantitatively on oncogenic Kras/Mek/Erk-induced hyperactive mTOR signalling.
No sample metadata fields
View SamplesAutoimmune pancreatitis (AIP) is a recently identified disease of the pancreas with unknown etiology and antigens. The aim of this study was to determine new target antigens and differentially regulated genes and proteins by means of transcriptomics and proteomics and to validate them in patients with autoimmune pancreatitis. Here we report a distinct downregulation at the RNA and protein level of pancreatic proteases (anionic trypsinogen, cationic trypsinogen, mesotrypsinogen, elastase IIIB) and pancreatic stone protein in autoimmune pancreatitis in comparison to alcohol-induced chronic pancreatitis.
Autoantibodies against the exocrine pancreas in autoimmune pancreatitis: gene and protein expression profiling and immunoassays identify pancreatic enzymes as a major target of the inflammatory process.
Sex, Age, Specimen part, Disease
View SamplesOzone is a highly toxic air pollutant and global health concern. Mechanisms of genetic susceptibility to ozone-induced lung inflammation are not completely understood. We hypothesized Notch3 and Notch4 are important determinants of susceptibility to ozone-induced lung inflammation. Wild type (WT), Notch3 (Notch3-/-) and Notch4 (Notch4-/-) knockout mice were exposed to ozone (0.3 ppm) or filtered air for 6-72 hours. Ozone increased bronchoalveolar lavage fluid (BALF) protein, a marker of lung permeability, in all genotypes, but significantly greater concentrations were found in Notch4-/- compared to WT and Notch3-/-. Significantly greater mean numbers of BALF neutrophils were found in Notch3-/- and Notch4-/- mice compared to WT mice after ozone. Expression of whole lung Tnf was significantly increased after ozone in all genotypes, and was significantly greater in Notch3-/- mice compared to WT. Statistical analyses of the transcriptome identified differentially expressed gene networks between WT and knockout mice basally and after ozone, and included Trim30, a member of the inflammasome pathway, and Traf6, an inflammatory signaling member. These novel findings are consistent with Notch3 and Notch4 as susceptibility genes for ozone-induced lung injury, and suggest that Notch receptors protect against innate immune inflammation.
Novel Roles for Notch3 and Notch4 Receptors in Gene Expression and Susceptibility to Ozone-Induced Lung Inflammation in Mice.
Specimen part
View SamplesCell type specific transcriptome analysis from laser microdissected megaspore mother cells (MMC) from Arabidopsis thaliana (L.) Heynh., accession Landsberg erecta.
Transcriptome analysis of the Arabidopsis megaspore mother cell uncovers the importance of RNA helicases for plant germline development.
Sex, Specimen part, Subject
View SamplesNucellus tissue surrounding the megaspore mother cell in Arabidopsis thaliana (L.) Heynh. , accession Landsberg erecta, isolated by laser assisted microdissection
Transcriptome analysis of the Arabidopsis megaspore mother cell uncovers the importance of RNA helicases for plant germline development.
Specimen part, Subject
View SamplesThe goal of this study was to examine whether immune responses to Plasmodium chabaudi infection differ between the sexes and are altered by the presence of gonadal steroids. Gonadally-intact males were more likely than intact females to die following P. chabaudi infection, exhibit slower recovery from infection-associated weight loss, hypothermia, and anemia, have reduced IFN-associated gene expression and IFN production during peak parasitemia, and produce less antibody during the recovery phase of infection. Gonadectomy of male and female mice altered these sex-associated differences, suggesting that sex steroid hormone, in particular androgens and estrogens, may modulate immune responses to infection.
Involvement of gonadal steroids and gamma interferon in sex differences in response to blood-stage malaria infection.
No sample metadata fields
View SamplesWe previously identified toll-like receptor 4 (Tlr4) as a candidate gene responsible for ozone (O3)-induced pulmonary hyperpermeability and inflammation. The objective of this study was to determine the mechanism through which TLR4 modulates O3-induced pulmonary responses and to utilize transcriptomics to determine TLR4 effector molecules. C3H/HeJ (HeJ; Tlr4 mutant) and C3H/HeOuJ (OuJ; Tlr4 normal), mice were exposed continuously to 0.3 ppm O3 or filtered air for 6, 24, 48 or 72 hr. Affymetrix Mouse430A_MOE gene arrays were used to analyze lung homogenates from HeJ and OuJ mice followed using a bioinformatic analysis. Inflammation was assessed by bronchoalveolar lavage and molecular analysis by ELISA, immunoblotting, and transcription factor activity. TLR4 signals through both the MYD88-dependent and independent pathways in OuJ mice, which involves MAP kinase activation, NF-kappaB, AP-1, and KC. Microarray analyses identifiedTLR4 responsive genes for strain and time in OuJ versus HeJ mice (p<0.05). One significantly upregulated cluster of genes in OuJ were the heat shock proteins (Hspa1b; Hsp70), Hsp90ab1). Furthermore, O3-induced expression of HSP70 protein was increased in OuJ compared to HeJ mice following 24-48 h O3. Moreover, BAL polymorphonuclear leukocytes (PMN) and total protein were significantly reduced in response to O3 in Hspa1a/Hspa1btm1Dix (Hsp70-/-) compared to Hsp70+/+ mice (p<0.05). TLR4 signaling (MYD88-dependent), ERK1/2, AP-1 activity, and KC protein content were also significantly reduced after O3 exposure in Hsp70-/- compared to Hsp70+/+ mice (p<0.05). These studies suggest that HSP70 is involved in the regulation of O3-induced lung inflammation through the TLR4 pathway and provide evidence that HSP70 is an endogenous in vivo TLR4 ligand.
Identification of candidate genes downstream of TLR4 signaling after ozone exposure in mice: a role for heat-shock protein 70.
Sex, Specimen part, Treatment
View SamplesWe hypothesize that gene expression in the Type II cells of Nrf2+/+ and Nrf2-/- mice are divergent thus contributing the cell growth. More specifically, type II cells from Nrf2-/- mice have increased reactive oxygen species that cause the impaired cell growth. In order to test these hypotheses at the gene expression level, we utilized microarray analysis to examine transcriptional differences between Nrf2+/+ and Nrf2-/- cells.
Genetic dissection of the Nrf2-dependent redox signaling-regulated transcriptional programs of cell proliferation and cytoprotection.
No sample metadata fields
View SamplesConsumption of diets rich in fibers has been associated with several beneficial effects on gastrointestinal health. However, detailed studies on the molecular effects of fibers in colon are limited. In this study we investigated and compared the influence of five different fibers on the mucosal transcriptome, and luminal microbiota and SCFA concentrations in murine colon. Mice were fed diets enriched with fibers that differed in carbohydrate composition, namely inulin (IN), oligofructose (FOS), arabinoxylan (AX), guar gum (GG), resistant starch (RS) or a control diet (corn starch) for 10 days. Gene expression profiling revealed the regulation of specific, but also overlapping sets of epithelial genes by each fiber, which on a functional level were mainly linked to cell cycle and various metabolic pathways including fatty acid oxidation, tricarboxylic acid cycle, and electron transport chain. In addition, the transcription factor PPAR was predicted to be a prominent upstream regulator of these processes. Microbiota profiles were distinct per dietary fiber, but the fibers IN, FOS, AX and GG induced a common change in microbial groups. All dietary fibers, except resistant starch, increased SCFA concentrations but to a different extent. Multivariate data integration revealed strong correlations between the expression of genes involved in energy metabolism and the relative abundance of bacteria belonging to the group of Clostridium cluster XIVa, that are known butyrate producers. These findings illustrate the potential of multivariate data analysis to unravel simple relationships in complex systems.
Comparison of the effects of five dietary fibers on mucosal transcriptional profiles, and luminal microbiota composition and SCFA concentrations in murine colon.
Sex, Age, Specimen part
View Samples