Project description:Oxidative stress caused by Menadione or Hydrogen peroxide in synchronized Saccharomyces cerevisiae cultures. Alpha factor synchronized cultures (0.2-0.4 OD), treated at the beginning of S phase (25 min after release from G1 arrest) with either 2 mM Menadione (MD) or 0.24 mM Hydrogen peroxide (HP), show cell cycle effects. Cells treated with MD arrested at G1. Cells treated with HP delayed at S and then, after removal of HP at 135 minutes , continued the cell cycle, only to arrest at G2/M. Growth was carried out in 30C with shaking (295 rpm). Two time course experiments were performed with each oxidative stress agent, designated as H2O2 and H2O2_II, MD and MD_II. Keywords = oxidative stress Keywords = menadione Keywords = hydrogen peroxide Keywords = time course Keywords = cell cycle Keywords = yeast Keywords: other
Project description:Oxidative stress caused by Menadione or Hydrogen peroxide in synchronized Saccharomyces cerevisiae cultures. Alpha factor synchronized cultures (0.2-0.4 OD), treated at the beginning of S phase (25 min after release from G1 arrest) with either 2 mM Menadione (MD) or 0.24 mM Hydrogen peroxide (HP), show cell cycle effects. Cells treated with MD arrested at G1. Cells treated with HP delayed at S and then, after removal of HP at 135 minutes , continued the cell cycle, only to arrest at G2/M. Growth was carried out in 30C with shaking (295 rpm). Two time course experiments were performed with each oxidative stress agent, designated as H2O2 and H2O2_II, MD and MD_II. Keywords = oxidative stress Keywords = menadione Keywords = hydrogen peroxide Keywords = time course Keywords = cell cycle Keywords = yeast
Project description:We subjected yeast to two stresses, oxidative stress, which under current settings induces a fast and transient response in mRNA abundance, and DNA damage, which triggers a slow enduring response. Using microarrays we performed a conventional quantification of change in mRNA abundance. Experiment Overall Design: We used Affymetrix microarrays to quantify changes in mRNA abundance following oxidative stress (using hydrogen peroxide) and DNA damage stress (using methyl methanesulfonate) during a three-hour time course (0, 30 min, 60 min, 100 min, 140 min, 180 min).
Project description:Investigating the oxidative stress response: Candida glabrata strains were stressed with hydrogen peroxide and menadione (causing oxygen radicals) to induce the oxidative stress regulon, which is thought to be upregulated during the oxidative burst inside of phagocytic cells.
Project description:We examined the transcriptional changes observable under oxidative stress caused by menadione in Emericella nidulans. Keywords: time-course
Project description:To investigate the oxidant sensitivity of E/ER regulated gene expression, E/ER regulated genes are identified using E deprivation or ER-alpha siRNA knockdown; and oxidative stress responsive is determined by 8hr exposure to diamide, hydrogen peroxide and menadione Keywords: biomarker identification
Project description:Cbf1 is a basic helix-loop-helix transcription factor which regulates the expression of many genes of the sulphur assimilation pathway in yeast. Gamma-glutamylcysteine synthetase (GSH1), encoding the rate-limiting enzyme in glutathione biosynthesis, is constitutively elevated in cbf1 mutants indicating that Cbf1 normally represses GSH1 expression. We used transcriptional profiling to show that a number of antioxidant and stress genes are similarly repressed by Cbf1, consistent with the high oxidant tolerance of cbf1 mutants. Our data indicate that Cbf1 plays a key role in the regulation of gene expression during oxidative stress conditions induced by exposure to hydrogen peroxide. The Yap1 transcription factor induces GSH1 expression in response to hydrogen peroxide in a mechanism that does not require the Met4 transcription factor to overcome the inhibitory action of Cbf1. We show that hydrogen peroxide does not affect Cbf1 occupancy on the GSH1 promoter, but results in specific modification of Cbf1 by phosphorylation. Our data indicate that casein kinase (CK2) can directly phosphorylate Cbf1 in vitro. Furthermore, CK2 activity is required to phosphorylate Cbf1 and induce GSH1 expression in yeast cells in response to hydrogen peroxide. CK2 mutants are sensitive to hydrogen peroxide consistent with a role for CK2 in regulating the cellular response to oxidative stress. CK2 is a ubiquitous serine/threonine protein kinase and the finding that it is regulated by oxidative stress is particularly interesting, since there is increasing evidence that it is involved in a number of pathological conditions including cancer, neurodegenerative and cardiovascular diseases.
Project description:To investigate the oxidant sensitivity of E/ER regulated gene expression, E/ER regulated genes are identified using E deprivation or; ER-alpha siRNA knockdown; and oxidative stress responsive is determined by 8hr exposure to diamide, hydrogen peroxide and menadione Experiment Overall Design: MCF7 cells were treated under various conditions to identifiy oxidative stress responsive E/ER regulated genes. Association of these genes with respect to tumor phenotypes are assessed
Project description:Oxidative stress is a harmful condition in a cell, tissue, or organ, caused by an imbalnace between reactive oxygen species and other oxidants and the capacity of antioxidant defense systems to remove them. The budding yeast S. cerevisiae has been the major eukaryotic model for studies of response to oxidative stress. We used microarrays to study the genome-wide temporal response of the yeast S. cerevisiae to oxidative stress induced by cumene hydroperoxide. Keywords: time course
Project description:Oxidative stress is a harmful condition in a cell, tissue, or organ, caused by an imbalnace between reactive oxygen species and other oxidants and the capacity of antioxidant defense systems to remove them. The budding yeast S. cerevisiae has been the major eukaryotic model for studies of response to oxidative stress. We used microarrays to study the genome-wide temporal response of the yeast S. cerevisiae to oxidative stress induced by cumene hydroperoxide. Keywords: time course
