Project description:RNA-seq was used to assess mRNA transcript abundance in wild type and fra2Δ S. cerevisiae (BY4741) cells treated with 2-(6-benzyl-2-pyridyl)quinazoline (BPQ) and CuSO4. BPQ potentiates copper toxicity and in yeast, in common with other organisms, a major cause of copper toxicity is damage of iron-sulphur clusters. Iron sensing within yeast relies on mitochondrial iron-sulphur cluster biosynthesis and therefore treatment with BPQ and copper can be used to mimic iron deficiency. Fra2 is known to be a key component of the iron sensing mechanism; however, this mechanism can operate, to an extent, independently of Fra2. BPQ (+CuSO4) treatment was used with the aim of probing the regulation of the iron regulon of S. cerevisiae and the role of Fra2 in the suppression of the low iron response. This study has uncovered nine new Cth2 target-transcripts, plus a new Aft1 target-gene and paralogous non-target. Fra2 dominates basal repression of the iron regulon in iron-replete cultures, however, Fra2-independent control of the iron regulon is also observed with CTH2 appearing to be atypically Fra2-dependent. Transcripts from untreated and CuSO4 treated cells were included as controls.
Project description:RNA-seq was used to assess mRNA transcript abundance in wild type and fra2M-NM-^T S. cerevisiae (BY4741) cells treated with 2-(6-benzyl-2-pyridyl)quinazoline (BPQ) and CuSO4. BPQ potentiates copper toxicity and in yeast, in common with other organisms, a major cause of copper toxicity is damage of iron-sulphur clusters. Iron sensing within yeast relies on mitochondrial iron-sulphur cluster biosynthesis and therefore treatment with BPQ and copper can be used to mimic iron deficiency. Fra2 is known to be a key component of the iron sensing mechanism; however, this mechanism can operate, to an extent, independently of Fra2. BPQ (+CuSO4) treatment was used with the aim of probing the regulation of the iron regulon of S. cerevisiae and the role of Fra2 in the suppression of the low iron response. This study has uncovered nine new Cth2 target-transcripts, plus a new Aft1 target-gene and paralogous non-target. Fra2 dominates basal repression of the iron regulon in iron-replete cultures, however, Fra2-independent control of the iron regulon is also observed with CTH2 appearing to be atypically Fra2-dependent. Transcripts from untreated and CuSO4 treated cells were included as controls. Three independent biological replicates were analysed for each condition (BPQ and CuSO4 treated wild type and fra2M-NM-^T cells, CuSO4 treated wild type and fra2M-NM-^T cells and untreated wild type and fra2M-NM-^T cells)
Project description:Iron is an essential cofactor for enzymes involved in numerous cellular processes. We analyzed the metabolomes and transcriptomes of yeast grown in iron-rich and iron-poor media to determine which biosynthetic processes are altered when iron availability falls. Saccharomyces cerevisiae DBY7286 strain was grown from very low density to mid-log phase (A600 = 0.5, approximately 18 hrs.) in defined-iron SD minimal medium containing only the supplements necessary to meet auxotrophic requirements. Defined-iron SD minimal media were prepared with yeast nitrogen base lacking iron and copper, supplemented with 1 µM copper sulfate, 25 mM MES pH 6.1, 1 mM Ferrozine (Fluka), and the indicated concentrations of ferrous ammonium sulfate 10 µM (low iron) or 300 µM (high iron). All cells were grown at 30°C with shaking and four independent cultures were prepared for each growth condition
Project description:Correlations between the chemical structures of agricultural fungicides and mRNA expression levels following exposure of Saccharomyces cerevisiae to toxic doses of thiuram, zineb, maneb, TPN, and PCP were examined. Structurally, thiuram, zineb, and maneb are dithiocarbamate fungicides, whereas TPN and PCP are not. To characterize chemical toxicity, genes expression was classified according to the functional groups used by the MIPS database. However, no correlations between the classification scheme and chemical structures were found. Hierarchical clustering of gene expression profiles was performed to characterize the effects of the five chemicals. According to this analysis the similarity of gene expression profiles depended on the similarity of chemical structures. These results suggest that DNA microarray technology has potential for predicting the major chemicals which will cause environmental toxicity and will provide information on new biomonitoring methods. Keywords: stress response
Project description:This SuperSeries is composed of the following subset Series: GSE18240: Saccharomyces cerevisiae cells: control vs positive supercoiling accumulation after 0, 30 and 120 min GSE18241: S. cerevisiae cells: control vs positive supercoiling accumulation in absence of telomere silencing after 0 and 120 min GSE18605: Saccharomyces cerevisiae cells: effect of Top2 depletion without accumulation of positive superhelical stress Refer to individual Series
Project description:Clioquinol (CQ or iodochlorhydroxyquin, 5-chloro-7-iodo-8-hydroxyquinoline) is a hydrophobic chelator of copper, zinc, and iron. It was extensively used as an antibiotic for the treatment of diarrhea and skin infection in the mid-1900s, but then withdrawn because it was reported to be associated with subacute myelo-optic neuropathy (SMON) in Japan. Interest in this drug was recently revived as it was shown that CQ specifically kills cancer cells and significantly decreases Aβ level. Nevertheless, the underlying mechanisms of CQ’s drug effects and side effects are still unclear. We used yeast, Saccharomyces cerevisiae, as a model to study how CQ affects molecular and cellular functions. Genechip analysis was utilized to examine the effect of CQ on gene expression at the genomic level.
Project description:Saccharomyces cerevisiae cells were exposed to a copper chelator (100uM BCS) for 48 hours. Samples were compared to the zero hour timepoint at 0.5, 1, 2, 3, 4, 24 and 48 hours.
Project description:This study investigates the transcriptomic responses of Saccharomyces cerevisiae S96 normal and petite cells to 4-Methylcyclohexanemethanol (MCHM), a coal cleaning chemical spilled in the water supply of central West Virginia in 2014.
Project description:Saxitoxin is a potent neurotoxin produced by several species of dinoflagellates and cyanobacteria. The molecular target of saxitoxin in higher eukaryotes is the voltage-gated sodium channel; however, its target in lower eukaryotic organisms remains unknown. The goal of this study was to obtain the transcriptional fingerprint of the model lower eukaryote Saccharomyces cerevisiae upon exposure to saxitoxin to identify potential genes suitable for biomarker development. Microarray analyses identified multiple genes associated with copper and iron homeostasis and sulfur metabolism as significantly differentially expressed upon exposure to saxitoxin; these results were verified with quantitative reverse-transcriptase PCR (qRT-PCR). Additionally, the qRT-PCR assays were used to generate expression profiles in a subset of the differentially regulated genes across multiple exposure times and concentrations, the results of which demonstrated that overall, genes tended to respond in a consistent manner to the toxin. In general, the genes encoding the metallothioneins CUP1 and CRS5 were induced following exposure to saxitoxin, while those encoding the ferric/cupric reductase FRE1 and the copper uptake transporter CTR1 were repressed. The gene encoding the multicopper ferroxidase FET3, part of the high-affinity iron uptake system, was also induced in all treatments, along with the STR3 gene, which codes for the cystathionine beta-lyase found in the methionine biosynthetic pathway.