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GSE10554
Saccharomyces cerevisiae
6 Downloadable Samples
Affymetrix Yeast Genome S98 Array (ygs98)
Description
Background: Pterostilbene, a naturally occurring phenolic compound produced by agronomically important plant genera such as Vitis and Vacciunium, is a phytoalexin exhibiting potent antifungal activity. Additionally, recent studies have demonstrated several important pharmacological properties associated with pterostilbene. Despite this, a systematic study of the effects of pterostilbene on eukaryotic cells at the molecular level has not been previously reported. Thus, the aim of the present study was to identify the cellular pathways affected by pterostilbene by performing transcript profiling studies, employing the model yeast Saccharomyces cerevisiae. Methods: S. cerevisiae strain S288C was exposed to pterostilbene at the IC50 concentration (70 uM) for one generation (3 h). Transcript profiling experiments were performed on three biological replicate samples using the Affymetrix GeneChip Yeast Genome S98 Array. The data were analyzed using the statistical methods available in the GeneSifter microarray data analysis system. To validate the results, eleven differentially expressed genes were further examined by quantitative real-time RT-PCR, and S. cerevisiae mutant strains with deletions in these genes were analyzed for altered sensitivity to pterostilbene. Results: Transcript profiling studies revealed that pterostilbene exposure significantly down-regulated the expression of genes involved in methionine metabolism, while the expression of genes involved in mitochondrial functions, drug detoxification, and transcription factor activity were significantly up-regulated. Additional analyses revealed that a large number of genes involved in lipid metabolism were also affected by pterostilbene treatment. Conclusions: Using transcript profiling, we have identified the cellular pathways targeted by pterostilbene, an analog of resveratrol. The observed response in lipid metabolism genes is consistent with its known hypolipidemic properties, and the induction of mitochondrial genes is consistent with its demonstrated role in apoptosis in human cancer cell lines. Furthermore, our data show that pterostilbene has a significant effect on methionine metabolism, a previously unreported effect for this compound.
Publication Title
Identification of molecular pathways affected by pterostilbene, a natural dimethylether analog of resveratrol.
Sample Metadata Fields
No sample metadata fields
View Samples- Saccharomyces cerevisiae, Candida albicans
- 8 Downloadable Samples
- Affymetrix Yeast Genome 2.0 Array (yeast2)
Description
6-Nonadecynoic acid (6-NDA), a plant-derived acetylenic acid, exhibits strong inhibitory activity against the human fungal pathogens Candida albicans, Aspergillus fumigatus, and Trichophyton mentagrophytes. In the present study, transcriptional profiling coupled with mutant and biochemical analyses were conducted using the model organism Saccharomyces cerevisiae to investigate the mechanism of action of this compound. 6-NDA elicited a transcriptome response indicative of fatty acid stress, altering the expression of genes known to be affected when yeast cells are grown in the presence of oleate. Mutants of S. cerevisiae lacking transcription factors that regulate fatty acid beta-oxidation showed increased sensitivity to 6-NDA. Fatty acid profile analysis indicated that 6-NDA inhibited the formation of fatty acids longer than 14 carbons in length. In addition, the growth inhibitory effect of 6-NDA was rescued in the presence of exogenously supplied oleate. To investigate the response of a pathogenic fungal species to 6-NDA, transcriptional profiling and biochemical analyses were also conducted in C. albicans. The transcriptional response and fatty acid profile of C. albicans were comparable to those obtained in S. cerevisiae, and the rescue of growth inhibition with exogenous oleate was also observed in C. albicans. In addition, 6-NDA enhanced the potency of the antifungal drug fluconazole in a fluconazole-resistant clinical isolate of C. albicans. Collectively, our results indicate that the antifungal activity of 6-NDA is mediated by a disruption in fatty acid homeostasis, and that this compound has potential utility in combination therapy in the treatment of drug-resistant fungal infections.
Publication Title
A potent plant-derived antifungal acetylenic acid mediates its activity by interfering with fatty acid homeostasis.
Sample Metadata Fields
No sample metadata fields
View Samples- Saccharomyces cerevisiae
- 29 Downloadable Samples
- Affymetrix Yeast Genome 2.0 Array (yeast2)
Description
Eupolauridine and liriodenine are plant-derived aporphinoid alkaloids that exhibit potent inhibitory activity against the opportunistic fungal pathogens Candida albicans and Cryptococcus neoformans. However, the molecular mechanism of this antifungal activity is unknown. In this study, we show that eupolauridine 9591 (E9591), a synthetic analog of eupolauridine, and liriodenine methiodide (LMT), a methiodide salt of liriodenine, mediate their antifungal activities by disrupting mitochondrial iron-sulfur (Fe-S) cluster synthesis. Several lines of evidence supported this conclusion. First, both E9591 and LMT elicited a transcriptional response indicative of iron imbalance, causing the induction of genes that are required for iron uptake and for the maintenance of cellular iron homeostasis. Second, a genome-wide fitness profile analysis showed that yeast mutants with deletions in iron homeostasisrelated genes were hypersensitive to E9591 and LMT. Third, treatment of wild-type yeast cells with E9591 or LMT generated cellular defects that mimicked deficiencies in mitochondrial Fe-S cluster synthesis, including an increase in mitochondrial iron levels, a decrease in the activities of Fe-S cluster enzymes, a decrease in respiratory function, and an increase in oxidative stress. Collectively, our results demonstrate that E9591 and LMT perturb mitochondrial Fe-S cluster biosynthesis; thus, these two compounds target a cellular pathway that is distinct from the pathways commonly targeted by clinically used antifungal drugs. Therefore, the identification of this pathway as a target for antifungal compounds has potential applications in the development of new antifungal therapies.
Publication Title
Two plant-derived aporphinoid alkaloids exert their antifungal activity by disrupting mitochondrial iron-sulfur cluster biosynthesis.
Sample Metadata Fields
No sample metadata fields
View Samples- Saccharomyces cerevisiae
- 8 Downloadable Samples
- Affymetrix Yeast Genome S98 Array (ygs98)
Description
Previously, it has been demonstrated that formate can be utilized by Saccharomyces cerevisiae as additional energy source using cells grown in a glucose-limited chemostat. Here, we investigated utilization of formaldehyde as co-substrate. Since endogenous formaldehyde dehydrogenase activities were insufficient to allow co-feeding of formaldehyde, the Hansenula polymorpha FLD1, encoding formaldehyde dehydrogenase, was introduced in S. cerevisiae. Chemostat cultivations revealed that formaldehyde was co-utilized with glucose, but the yield was lower than predicted. Moreover, formate was secreted by the cells. Upon co-expression of the H. polymorpha gene encoding formate dehydrogenase, FMD, the levels of secreted formate decreased, but the biomass yield was still lower than anticipated.
Publication Title
Engineering and analysis of a Saccharomyces cerevisiae strain that uses formaldehyde as an auxiliary substrate.
Sample Metadata Fields
No sample metadata fields
View Samples- Caenorhabditis elegans
- 146 Downloadable Samples
- Affymetrix C. elegans Genome Array (celegans)
Description
The principal toxicity of acute organophosphate (OP) pesticides poisoning is the disruption of neurotransmission through inhibition of acetylcholinesterase (AChE). However, other mechanisms leading to persistent effects and neurodegeneration remain controversial and difficult to detect. Because Caenorhabditis elegans is relatively resistant to OP lethalityparticularly through the inhibition of AChEstudies in this nematode provide an opportunity to observe alterations in global gene expression following OP exposure that cannot be readily observed in less resistant organisms.
Publication Title
Alterations in gene expression in Caenorhabditis elegans associated with organophosphate pesticide intoxication and recovery.
Sample Metadata Fields
No sample metadata fields
View Samples- Homo sapiens
- 4 Downloadable Samples
- Affymetrix Human Gene 1.0 ST Array (hugene10st)
Description
In order to identify novel genes regulated by p53, stable line containing tet-on inducible p53 construct was generated and used for gene expression analysis.
Publication Title
Ferroptosis as a p53-mediated activity during tumour suppression.
Sample Metadata Fields
Cell line
View Samples- Rattus norvegicus
- 9 Downloadable Samples
- Affymetrix Rat Genome 230 2.0 Array (rat2302)
Description
The objective of the study was to better understand the mechanism behind scar formation by identifying ECM factors and other unique genes differentially expressed during rat ligament healing via microarray. Rat medial collateral ligaments (MCL) were surgically transected or left intact. MCLs were collected at day 3 or 7 post-injury and used for microarray analysis. Results were compared to the normal intact ligaments.
Publication Title
Gene profiling of the rat medial collateral ligament during early healing using microarray analysis.
Sample Metadata Fields
Sex, Specimen part
View Samples- Rattus norvegicus
- 59 Downloadable Samples
- Affymetrix Rat Genome 230 2.0 Array (rat2302)
Description
U.S. Service Members and civilians are at risk of exposure to a variety of environmental health hazards throughout their normal duty activities and in industrial occupations. Metals are widely used in large quantities in a number of industrial processes and are a common environmental toxicant, which increases the possibility of being exposed at toxic levels. While metal toxicity has been widely studied, the exact mechanisms of toxicity remain unclear. In order to further elucidate these mechanisms and identify candidate biomarkers, rats were exposed via a single intraperitoneal injection to three concentrations of CdCl2 and Na2Cr2O7, with livers harvested at 1, 3, or 7 days after exposure. Cd and Cr accumulated in the liver at 1 day post exposure. Cd levels remained elevated over the length of the experiment, while Cr levels declined. Metal exposures induced ROS, including hydroxyl radical (OH), resulting in DNA strand breaks and lipid peroxidation. Interestingly, ROS and cellular damage appeared to increase with time post-exposure in both metals, despite declines in Cr levels. Differentially expressed genes were identified via microarray analysis. Both metals perturbed gene expression in pathways related to oxidative stress, metabolism, DNA damage, cell cycle, and inflammatory response. This work provides insight into the temporal effects and mechanistic pathways involved in acute metal intoxication, leading to the identification of candidate biomarkers.
Publication Title
Temporal changes in rat liver gene expression after acute cadmium and chromium exposure.
Sample Metadata Fields
Specimen part, Treatment
View Samples- Mus musculus
- 12 Downloadable Samples
- Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
Cells located at the invasive front and in the tumor mass of mouse cervical squamous cell carcinomas were isolated by laser microdissection from hematoxylin-stained HPV/E2 sections. 7 months old HPV/E2 mice treated with oestrogen develop invasive cervical squamous cell carcinomas. This model recapitulates human invasive cervical neoplasias.
Publication Title
Inflammatory Cytokines Induce Podoplanin Expression at the Tumor Invasive Front.
Sample Metadata Fields
Specimen part
View Samples- Rattus norvegicus
- 139 Downloadable Samples
- Affymetrix Rat Gene 1.1 ST Array (ragene11st)
Description
Background: The in vivo gene response associated with hyperthermia and subsequent return to homeostasis or development of heat illness is poorly understood. Early activation of gene networks in the heat stress response is likely to lead to the systemic inflammation, multi-organ functional impairment, and other pathophysiological states characteristic of heat illness. Here, we perform an unbiased global characterization of the multi-organ gene response using an in vivo model of heat stress in the conscious rat.
Publication Title
Patterns of gene expression associated with recovery and injury in heat-stressed rats.
Sample Metadata Fields
Sex, Specimen part
View Samples