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GSE10091
Saccharomyces cerevisiae
4 Downloadable Samples
Affymetrix Yeast Genome S98 Array (ygs98)
Description
The accumulation of unfolded proteins in the lumen of the endoplasmic reticulum (ER) causes stress and induces the unfolded protein response (UPR) which is characterised in part by the transcriptional induction of genes involved in assisting protein folding. Translational responses to ER stress have been less well described and here we report on a genome-wide analysis of translational regulation in the response to the ER stress-inducing agent dithiothreitol (DTT) in Saccharomyces cerevisiae. Although the observed polysome profiles were similar under control and ER stress conditions microarray analysis identified transcipt-specific translational regulation. Genes with functions in ribosomal biogenesis and assembly were translationally repressed under ER stress. In contrast mRNAs for known UPR genes, including the UPR transcription factor HAC1, the ER-oxidoreductase ERO1 and the ER-associated protein degradation (ERAD) gene DER1 were enriched in polysomal fractions under ER stress conditions. In addition, we show that splicing of HAC1 mRNA is required for efficient ribosomal loading and that Gcn2p is required for normal HAC1 splicing, so shedding light on the role of this protein kinase in the UPR pathway.
Publication Title
Transcript-specific translational regulation in the unfolded protein response of Saccharomyces cerevisiae.
Sample Metadata Fields
No sample metadata fields
View Samples- Saccharomyces cerevisiae
- 27 Downloadable Samples
- Affymetrix Yeast Genome 2.0 Array (yeast2)
Description
Functional genomic analysis using different types of baker's yeast.
Publication Title
No associated publication
Sample Metadata Fields
No sample metadata fields
View Samples- Saccharomyces cerevisiae
- 14 Downloadable Samples
- Affymetrix Yeast Genome 2.0 Array (yeast2)
Description
Genes whose expression correlated to the degree of thermotolerance in S. cerevisiae were identified by DNA microarray analysis.
Publication Title
Identification of a gene, FMP21, whose expression levels are involved in thermotolerance in Saccharomyces cerevisiae.
Sample Metadata Fields
No sample metadata fields
View Samples- Saccharomyces cerevisiae
- 9 Downloadable Samples
- Affymetrix Yeast Genome 2.0 Array (yeast2)
Description
Saccharomyces cerevisiae is exposed to freeze-thaw stress in commercial processes including frozen dough baking. The cell viability and fermentation activity after freeze-thaw were dramatically decreased due to freeze-thaw injury. Because freeze-thaw injury involves complex phenomena, the mechanisms of it are not fully understood. We attempted to analyze the mechanisms of freeze-thaw injury by indirect gene expression analysis during post-thaw incubation after freeze-thaw treatment using DNA microarray profiling. The results showed that a high frequency of the genes involved in the homeostasis of metal ions were up-regulated depending on the freezing period. The phenotype of the deletion mutants of the up-regulated genes extracted by indirect gene expression analysis was assessed. The deletion strains of the MAC1 and CTR1 genes involved in copper ion homeostasis exhibited freeze-thaw sensitivity, suggesting that copper ion homeostasis is required for freeze-thaw tolerance. Supplementation with copper ions during post-thaw incubation increased intracellular superoxide dismutase activity. Inverse correlated with intracellular superoxide dismutase activity, intracellular levels of reactive oxygen species were decreased. Moreover, cell viability increased by supplementation with copper ions under specific assessment conditions. This study suggested that insufficiency of copper ion homeostasis may be one of the causes of freeze-thaw injury.
Publication Title
Insufficiency of copper ion homeostasis causes freeze-thaw injury of yeast cells as revealed by indirect gene expression analysis.
Sample Metadata Fields
No sample metadata fields
View Samples- Saccharomyces cerevisiae
- 8 Downloadable Samples
- Affymetrix Yeast Genome 2.0 Array (yeast2)
Description
Genes whose expression correlated to the acetic acid tolerance in S. cerevisiae were identified by DNA microarray analysis.
Publication Title
Identification of an acetate-tolerant strain of Saccharomyces cerevisiae and characterization by gene expression analysis.
Sample Metadata Fields
Treatment
View Samples- Saccharomyces cerevisiae
- 8 Downloadable Samples
- Affymetrix Yeast Genome S98 Array (ygs98)
Description
Frozen dough baking is useful method in the modern bread-making industry. However, the fermentation activity of bakers yeast dramatically decreased after thawing due to freeze injuries, because bakers yeast cells contained in dough experience freeze injuries during freeze-thaw processes. Here, we performed genome-wide expression analysis to determine genetic response in bakers yeasts under freeze-thaw condition using a DNA microarray analysis. Functional and clustering analyses in gene expression reveal that genes could be characterized by the term of freeze-thaw stress. Under short-term freeze stress (freeze treatment for 3 day), genes involved in ribosomal protein were up-regulated. Under long-term freeze stress (freeze treatment for longer than 7 day), genes involved in energy synthesis were up-regulated. In each phase, genes involved in protein damage, several stresses and trehalose and glycogen metabolism were also up-regulated. Through these freeze stress, yeast cells may improve reduced efficiency of translation and enhanced cell protection mechanism to survive under freeze stress condition. These regulations of these genes would be controlled by the cAMP-protein kinase A pathway.
Publication Title
No associated publication
Sample Metadata Fields
No sample metadata fields
View Samples- Saccharomyces cerevisiae
- 6 Downloadable Samples
- Affymetrix Yeast Genome 2.0 Array (yeast2)
Description
EOS1 is required for tolerance to oxidative stress in Saccharomyces cerevisiae; mutants are defective in the gene sensitive to hydrogen peroxide and tolerant to tunicamycin. To clarify the function of Eos1, we screened yeast genomic DNA libraries for heterologous genes that, when overexpressed from a plasmid, can suppress the hydrogen peroxide-sensitive eos1 mutation. We identified such a gene as IZH2, which has previously been reported to be a Zap1-regulated gene. However, the EOS1 and IZH2 genes do not themselves appear to be functionally interchangeable. Double disruption of the EOS1 and IZH2 genes yielded a slow-growth phenotype, suggesting that the two proteins are involved in related cellular processes. DNA microarray analysis revealed decreased expression of Zap1-regulated genes in the eos1-deletion mutant (delta eos1). Thus, it is likely that Eos1 is involved in zinc homeostasis.
Publication Title
No associated publication
Sample Metadata Fields
No sample metadata fields
View Samples- Saccharomyces cerevisiae
- 6 Downloadable Samples
- Affymetrix Yeast Genome 2.0 Array (yeast2)
Description
In frozen dough baking technology, bakers yeast Saccharomyces cerevisiae encounter freeze-thaw injury. After thawing, dramatically decrease in cell viability and fermentation activity is caused by freeze-thaw injury. The freezing period is critical factor in freeze-thaw injury, thus we focused and investigated time-dependent gene expression profiles in recovery process from freeze injury. First, changes in gene expression profiles in S. cerevisiae in recovery process from freeze-thaw injury were analyzed using a DNA microarray. The results showed the genes which were involved in homeostasis of metal ions were time-dependent up-regulated 2-fold or more in a series. Then we examined whether these genes were related to tolerance in freeze-thaw injury by using deletion strain. The results showed that deletion of MAC1, CTR1, and PCA1 genes which involved in copper ion transport exhibited freeze-thaw sensitivity in compared with wild type. These genes are involved in copper ion uptake to a cell under a copper deficiency condition or in copper ion homeostasis, suggesting that it may be related between freeze-thaw injury and copper ion transport. To determine the effect of supplementation of copper ion on cells after freeze-thaw treatment, cell viability, intracellular superoxide dismutase (SOD) activity, and intracellular levels of reactive oxygen species (ROS) were examined by various copper ion condition medium. The results showed that intracellular SOD activity was increased and intracellular levels of ROS were decreased by supplementation of copper ion, but there was no significant difference in cell viability. These results of the present study may suggest that copper ion concentration in yeast cell after freeze-thaw treatment is important to recovery from freeze-thaw injury due to redox control of intracellular levels of ROS, but copper ion did not directly affect cell viability.
Publication Title
No associated publication
Sample Metadata Fields
No sample metadata fields
View Samples- Saccharomyces cerevisiae
- 4 Downloadable Samples
- Affymetrix Yeast Genome 2.0 Array (yeast2)
Description
The vanillin tolerance Saccharomyces cerevisiae was screened and compared intracellular ergosterol levels with several laboratory yeast strains, to study potential relationship between ergosterol contents and vanillin tolerance. S. cerevisiae NBRC1950 was selected as a vanillin tolerant strain. Its ergosterol contents were higher than those of laboratory strains. The results of DNA microarray and quantitative RT-PCR analysis showed that 5 genes involved in ergosterol biosynthesis (ERG28, HMG1, MCR1, ERG5 and ERG7) were up-regulated in NBRC 1950 compared with strain X2180, suggested that high expressions of genes involved in ergosterol biosynthesis may cause for the high ergosterol content in strain NBRC 1950. S. cerevisiae HX strain, which was a high ergosterol content strain derived from X2180, became more tolerant to vanillin compared with the parental strain. It is suggested that high ergosterol contents may be in part responsible for vanillin tolerance. These findings provide a biotechnological basis for the molecular engineering of S. cerevisiae with increased tolerance to vanillin.
Publication Title
Involvement of ergosterol in tolerance to vanillin, a potential inhibitor of bioethanol fermentation, in Saccharomyces cerevisiae.
Sample Metadata Fields
No sample metadata fields
View Samples- Mus musculus
- 27 Downloadable Samples
- Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
We examined the effect of quercetin on the gene expression and function of epididymal adipose tissue (EAT) in Western diet-induced obese mice. Quercetin suppressed the increase in the number of macrophages and the decrease in the ratio of CD4+ to CD8+ T cells in EAT, and the elevation of plasma leptin and TNF levels in mice fed the Western diet. Comprehensive gene expression analysis revealed that quercetin suppressed gene expression associated with the accumulation and activation of immune cells, including macrophages and lymphocytes in EAT. It also improved the expression of the oxidative stress-sensitive transcription factor NFB, NADPH oxidases, and antioxidant enzymes. Quercetin markedly increased gene expression associated with mitochondrial oxidative phosphorylation and mitochondrial DNA Quercetin most likely universally suppresses the accumulation and activation of immune cells, including anti-inflammatory cells, whereas it specifically increased gene expression associated with mitochondrial oxidative phosphorylation. Suppression of oxidative stress and NFB activity likely contributed to the prevention of the accumulation and activation of immune cells and resulting chronic inflammation.
Publication Title
Quercetin suppresses immune cell accumulation and improves mitochondrial gene expression in adipose tissue of diet-induced obese mice.
Sample Metadata Fields
Sex, Specimen part
View Samples