Expression data from the adipose tissue of mice fed a normal diet and a high fat diet.
ABSTRACT: To identify novel Peroxisome Proliferator-Activated Receptor gamma (PPARg) responsive secretory and/or transmembrane genes that is related to obesity, we integrated the expression data from the adipose tissue derived from obese mice with the other two data sets: expression profiling of adipocyte differentiation using ST2 cells and siRNA-mediated knockdown of Pparg during ST2 cell adipogenesis. We used microarrays to detect the up-regulated genes in adipose tissue derived from mice fed a high fat diet compared to a control. Total RNA from adipose tissue was obtained and from mice fed a high fat diet HFD32 (MOUSE_HFD) from 6 week-old to 18 week-old, or a normal diet CE-2 (MOUSE_ND) as a control. Pooled RNAs of each three animals were analyzed by the Affymetrix GeneChip microarray system.
Project description:Plants engineered for abiotic stress tolerance may soon be commercialized. The engineering of these plants typically involves the manipulation of complex multigene networks and may therefore have a greater potential to introduce pleiotropic effects than the simple monogenic traits that currently dominate the plant biotechnology market. Drought- tolerant Arabidopsis thaliana were engineered through overexpression of the transcription factor ABF3 in order to investigate unintended pleiotropic effects. In order to eliminate position effects, the Cre/lox recombination system was used to create control plant lines that contain identical T-DNA insertion sites but with the ABF3 transgene excised. This additionally allowed us to determine if Cre recombinase can cause unintended effects that impact the transcriptome. Microarray analysis of control plant lines that underwent Cre-mediated excision of the ABF3 transgene revealed only two genes that were differentially expressed in more than one plant line, suggesting that the impact of Cre recombinase on the transcriptome was minimal. In the absence of drought stress, overexpression of ABF3 had no effect on the transcriptome, but following drought stress, differences were observed in the gene expression patterns of plants overexpressing ABF3 relative to control plants. Examination of the functional distribution of the differentially expressed genes revealed strong similarity indicating that unintended pathways were not activated. In response to drought stress, overexpression of ABF3 results in a reprogramming of the drought response, which is characterized by changes in the timing or strength of expression of some drought response genes, without activating any unexpected gene networks. These results illustrate that important gene networks are highly regulated in Arabidopsis and that engineering stress tolerance may not necessarily cause extensive changes to the transcriptome.
Project description:c-Myc is one of key players that are crucially involved in maintaining the undifferentiated state and the self-renewal of ESCs. To understand the mechanism by which c-Myc helps preserve these prominent characteristics of ESCs, we generated null-ES cells for the Max gene, which encodes the best characterized partner protein for all Myc family proteins. Although Myc/Max complexes have been widely regarded as crucial regulators of the ESC status, our data reveal that ESCs do not absolutely require these complexes in so-called ground state or related conditons and that this requirement is restricted to conventional ES culture conditions without using a MAPK inhibitor. Simply Dox-treated or Nanog (WT or D67G mutant)-rescued Max-null ESCs which were cultured under conventional culture condition and 2i/Nam-treated completely Max-null ES cells from which Dox-regulatable cDNA was removed were used for RNA source. Samples from Dox-untreated Max-null ESCs cultured under conventional culture condition were used as reference samples for Dox-treated cells and Nanog-rescued cells, while a sample from wild-type ESCs cultured under 2i/Nam condition was used as a reference sample for completely Max-null ES cells cultured with 2i/Nam.
Project description:Gene expression profile of squamous lung cancer cells are used to identify genes that are differentially regulated. Experiment Overall Design: Each pair of samples represent a single patient with squamous lung cancer. One is derived from the cancer cells, and the other is from the normal cells. Five patients, with two arrays for each patients.
Project description:Subinhibitory concentrations of the neuroleptic drug thioridazine (TDZ) are well-known to enhance the killing of methicillin-resistant S. aureus (MRSA) by β-lactam antibiotics, however, the mechanism underlying the synergy between TDZ and β-lactams is not fully understood. In the present study we have examined the effect of a subinhibitory concentration of TDZ on antimicrobial resistance, the global transcriptome, and the cell wall composition of MRSA USA300. We show that TDZ is able to sensitize the bacteria to several classes of antimicrobials targeting the late stages of peptidoglycan synthesis. Furthermore, our microarray analysis demonstrates that TDZ modulates the expression of genes encoding membrane and surface proteins, transporters, and enzymes involved in amino acid biosynthesis. Interestingly, resemblance between the transcriptional profile of TDZ treatment and the transcriptomic response of S. aureus to known inhibitors of cell wall synthesis suggests that TDZ disturbs peptidoglycan biosynthesis at a stage that precedes transpeptidation. In support of this notion, dramatic changes in the muropeptide profile of USA300 were observed following growth in the presence of TDZ, indicating that TDZ can interfere with the formation of the pentaglycine branches. Strikingly, the addition of glycine to the growth medium relieved the effect of TDZ on the muropeptide profile. Furthermore, exogenous glycine offered a modest protective effect against TDZ-induced β-lactam sensitivity. We propose that TDZ exposure leads to a shortage of intracellular amino acids, including glycine, which is required for the production of normal peptidoglycan precursors with pentaglycine branches, the correct substrate of S. aureus penicillin-binding proteins. Collectively, this work demonstrates that TDZ has a major impact on the cell wall biosynthesis pathway in S. aureus and provides new insights into how MRSA may be sensitized towards β-lactam antibiotics. Staphylococcus aureus USA300 was grown to early exponential phase and treated with TDZ (16 µg/ml) alone or in combination with DCX (0.125 µg/ml) for 30 min. Changes in global gene expression were analyzed using the untreated culture as control. Hybridizations were performed in triplicate using RNA isolated from independent cultures.
Project description:We explored Max ablation-mediated up-regulation of germ-related genes, especially meiosis-related genes in mouse embryonic stem cells which were cultured either under conventional mouse ES medium or 2i condition using inhibitors against MEK and GSK3b. Effect of culture conditions (conventional mouse ES medium or 2i condition) on the expression profile of germ-related genes in Max expression ablated ES cells were examined using inducible Max-null ES cells in which Max gene had been homozygously disrupted, but carries Max cDNA in ROSA26 locus with tetracycline-off system.
Project description:We explored the relationship between Myc activity and PI3K signaling in ESCs. Our data demonstrate that Myc and PI3K signaling function cooperatively for supporting pluripotent property of ESCs. Moreover, our data demonstrate that exposure of ESCs to 2i condition render both Myc and PI3K dispensable for preserving ESC status. Effect of PI3K inhibitor, LY4294002 on EBRTcH3 ESCs or their derivatives overexpressing c-Myc (wild-type or T58A mutant) was examined. Effect of LY4294002 on EBRTcH3 ESCs under 2i conditions was also examined. Furthermore, effect of Max expression ablation was compared between ESCs and those overexpressing p110 alpha.
Project description:Nucleostemin (NS) gene is known to be expressed in stem cells in general including embryonic stem cells (ESCs). Previous knockdown and knockout studies have demonstrated that NS is important for the preservation of their self-renewality and high levels of pluripotent marker gene expression in mouse ESCs. In this study, we demonstrate that the forced expression of Nanog or Esrrb, but not other pluripotency factors, made NS expression dispensable in mouse ESCs. DNA microarray data deposited here underscored the notion that both Nanog and Esrrb could rather faithfully counteract the alteration of gene expression profile caused by NS expression ablation in ESCs. NS tet off ESCs (Stem Cells 27, 1066-1076, 2009) in which NS gene was homozygously disrupted, but NS cDNA was introduced in ROSA26 gene locus together with tetracycline-off system were used as parental ESCs to examine the effect of NS expression ablation in ESCs. In this study, how alteration of gene expression profile change associated with NS expression ablation was modulated by the forced expression of either constitutively active Stat3 (Stat3mut), Nanog or Esrrb. Effect obtained by the exposure to 2i condition (medium containing 2 kinase inhibitors against MEK and GSK3b) was also examined
Project description:Methylmercury (MeHg) is a highly toxic environmental pollutant. To understand the mechanisms of toxicity of the compound and possibly to discover new biomarkers for environmental monitoring, we have conducted toxicogenomics studies. We designed 126k-cod-oligonucleotide arrays and performed genome-wide gene expression assays in liver samples from juvenile cod treated with MeHg (0.5 and 2 mg/kg body weight). Microarray analysis showed MeHg differentially regulated hundreds of genes. Gene Ontology and pathway analyses of differentially regulated genes revealed that MeHg modulated mainly genes involved in immune response, oxidative stress response, tissue remodelling, and energy pathways such as lipid, carbohydrate and amino acid metabolism. The results provide insights into the mechanisms of toxicity of MeHg and provide candidate biomarkers of exposure to MeHg for further evaluation. Analyzed 5 samples from each of 3 groups: control, 0.5 mg/BW MeHg treated, and 2 mg/BW MeHg treated. Liver total RNA was reverse transcribed, Cy3-labeled, and hybridized (one-color hybridzation).