Project description:Samples GSM206658-GSM206693: Acquired Stress resistance in S. cerevisiae: NaCl primary and H2O2 secondary Transcriptional timecourses of yeast cells exposed to 0.7M NaCl alone, 0.5mM H2O2 alone, or 0.5mM H2O2 following 0.7M NaCl, all compared to an unstressed sample. Repeated using msn2∆ strain. Samples GSM291156-GSM291196: Transcriptional response to stress in strains lacking MSN2 and/or MSN4 Transcriptional timecourses of yeast cells (WT, msn2∆, msn4∆, or msn2∆msn4∆) exposed to 0.7M NaCl for 45 minutes or 30-37˚C Heat Shift for 15 min compared to an unstressed sample of the same strain. Keywords: Stress Response
Project description:To gain deep understanding of yeast cell response to heat stress, multiple laboratory strains have been intensively studied by genome-wide expression analysis for mechanistic dissection of classical heat shock response. However, robust industrial strains of S. cerevisiae have hardly been explored in global analysis for elucidating the mechanism of thermotolerant response (TR) during fermentation. Herein, we employed DIA/SWATH–based proteomic workflows to characterize proteome remodeling of an industrial strain ScY01 responding to prolonged thermal stress or transient heat shock.
Project description:In the yeast Saccharomyces cerevisiae, accumulation of misfolded proteins in the endoplasmic reticulum (ER) causes ER stress and activates the unfolded protein response (UPR) mediated by Hac1p, whereas the heat shock response (HSR) mediated by Hsf1p mainly regulates cytosolic processes and protects the cell from different stresses. In this study, we find that a constitutive activation of the HSR by over-expression of a mutant HSF1 gene could relieve ER stress in both wild type and hac1∆ UPR-deficient cells. We studied the genome-wide transcriptional response in order to identify regulatory mechanisms that govern the interplay between UPR and HSR responses. Interestingly, we find that the regulation of ER stress via HSR is mainly through facilitation of protein folding and secretion and not via the induction of Rpn4-dependent proteasomal activity.
Project description:In the yeast Saccharomyces cerevisiae, accumulation of misfolded proteins in the endoplasmic reticulum (ER) causes ER stress and activates the unfolded protein response (UPR) mediated by Hac1p, whereas the heat shock response (HSR) mediated by Hsf1p mainly regulates cytosolic processes and protects the cell from different stresses. In this study, we find that a constitutive activation of the HSR by over-expression of a mutant HSF1 gene could relieve ER stress in both wild type and hac1delta UPR-deficient cells. We studied the genome-wide transcriptional response in order to identify regulatory mechanisms that govern the interplay between UPR and HSR responses. Interestingly, we find that the regulation of ER stress via HSR is mainly through facilitation of protein folding and secretion and not via the induction of Rpn4-dependent proteasomal activity. Four Saccharomyces cerevisiae strains, WT, WT(hsf1), hac1delta and hac1delta(hsf1), were grown in SD-URA medium and treated with 2.5 mM DTT. After two hours induction, samples were taken for RNA extraction and hybridization on Affymetrix microarrays. Biological triplicates were applied.
Project description:To better understand how yeast adapt and respond to sequential stressors, an industrial yeast strain, URM 6670 (also known as BT0510), which is highly flocculent, tolerant to ethanol, osmotic and heat shock stresses, was subjected to three different treatments: 1. osmotic stress followed by ethanol stress, 2. oxidative stress followed by ethanol stress, 3. glucose withdrawal followed by ethanol stress. Samples were collected before the first stress (control), after the first stress and after the second stress (ethanol). RNA was extracted and analyzed by RNAseq.
Project description:We developed an artificial genome evolution system, which we termed ‘TAQing’, by introducing multiple genomic DNA double-strand breaks using a heat-activatable endonuclease in mitotic yeast. The heat-activated endonuclease, TaqI, induced random DSBs, which resulted in diverse types of chromosomal rearrangements including translocations. Array comparative genomic hybridization (aCGH) analysis was performed with cell-fused Saccharomyces cerevisiae strains induced genome evolution by TAQing system. Some of copy number variations (CNVs) induced by massive genome rearrangements were detected in the TAQed yeast strains.
Project description:The Saccharomyces cerevisiae MYO1 gene encodes the myosin type II heavy chain (Myo1p), a protein required for normal cytokinesis in budding yeast. Deletion of the MYO1 gene prevents actomyosin-driven cytokinesis thereby activating an alternative mechanism that involves the synthesis of a remedial septum. Myo1p deficiency in yeast (myo1) also causes the formation of attached cells, abnormal budding patterns, formation of enlarged and elongated cells, increased osmotic sensitivity, delocalized chitin deposition, and increased chitin synthesis. To determine how the differential expression of genes is related to these diverse phenotypes, we analyzed the global mRNA expression profile of myo1 strains. Global mRNA expression profiles of myo1 strains and their corresponding wild type controls were obtained by hybridization to yeast oligonucleotide microarrays. Results for selected genes were confirmed by real time RT-PCR. A total of 547 differentially expressed genes were identified with 263 up-regulated and 284 down regulated genes in the myo1 strains. Gene set enrichment analysis revealed the significant over-representation of genes in the protein biosynthesis and stress response categories. Genes involved in cell wall assembly (GAS1, PSA1, CIS3, FIT1, WSC2), MAP kinase activity (SLT2), Rho1p Guanine Exchange Factor (ROM1), and regulation of cell proliferation (RAS1) were also differentially expressed in myo1 strains. Conclusions: We have presented a global mRNA expression analysis of yeast myo1 strains and hypothesized about possible correlations with morphological and biochemical phenotypes observed in these strains. We report 547 differentially regulated genes in the myo1 mutant strains. Genes involved in the control of cell proliferation, protein synthesis and maturation, DNA replication, and cell division processes were largely down regulated, suggesting a mechanism for delayed cell cycle progression and growth that involves coordinated regulation of these processes in myo1 strains. Other genes involved in the cellular response to cell wall stress and cell wall organization were largely up-regulated suggesting that cell wall biogenesis is important for the completion of cytokinesis and cell wall morphogenetic processes that may also be affected by myosin II deficiency. Gene set enrichment analysis indicates that stress response and protein biosynthesis gene categories are inversely correlated in this mutant. Keywords: Comparative genomic hybridization