Project description:In this experiment we tested the transcriptome of transgenic Arabidopsis seedlings (5-day-old) constitutively expressing the zinc-finger protein Zat12 (At5g59820) under the control of the 35S-CaMV promoter (Zat12). The transcriptome of these seedlings was compared to that of wild type seedlings grown under the same conditions (WT) and to that of wild type seedlings grown under the same conditions and subjected to a hydrogen peroxide stress (WT+H2O2). Hydrogen peroxide treatment was performed by applying 20 mM hydrogen peroxide for 1 hour. In parallel to these experiments transgenic plants expressing Zat12 were subjected to a similar hydrogen peroxide stress (Zat12+H2O2). All treatments were performed with similar size and age seedlings grown in liquid culture (MS) and sampled at the same time as described by Davletova et al., 2005. Experimenter name = Ron Mittler Experimenter phone = 1-775-784-1384 Experimenter fax = 1-775-784-1650 Experimenter department = Dept. of Biochemistry Experimenter institute = University of Nevada Experimenter address = MS200 Experimenter address = Reno Experimenter address = Nevada Experimenter zip/postal_code = 89557 Experimenter country = USA Keywords: genetic_modification_design; stimulus_or_stress_design
Project description:Using data from microarray experiments, we investigated the effects of excess hydrogen peroxide on D. vulgaris. Keywords: stress response, time course Comparison of cells treated with 1 mM H2O2,sterile water Peroxide to untreated cells at times of 0,120,240,30,480,60 min.
Project description:Adaptation to hydrogen peroxide in Saccharomyces cerevisiae is profiled with expression arrays. Adaptation describes the process in which a mild dose of toxin (in this case, hydrogen peroxide) is able to protect against a later acute dose. Here, we study two adaptive protocols (0.1 mM H2O2 and 0.1 + 0.4 mM H2O2) and one acute protocol (0.4 mM H2O2) to identify processes uniquely involved in adaptation. Predictions from these studies are validated in expression profiling of deletion mutants of the transcription factors Yap1, Mga2, and Rox1.
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:In this experiment we tested the transcriptome of transgenic Arabidopsis seedlings (5-day-old) constitutively expressing the zinc-finger protein Zat12 (At5g59820) under the control of the 35S-CaMV promoter (Zat12). The transcriptome of these seedlings was compared to that of wild type seedlings grown under the same conditions (WT) and to that of wild type seedlings grown under the same conditions and subjected to a hydrogen peroxide stress (WT+H2O2). Hydrogen peroxide treatment was performed by applying 20 mM hydrogen peroxide for 1 hour. In parallel to these experiments transgenic plants expressing Zat12 were subjected to a similar hydrogen peroxide stress (Zat12+H2O2). All treatments were performed with similar size and age seedlings grown in liquid culture (MS) and sampled at the same time as described by Davletova et al., 2005. Experimenter name = Ron Mittler; Experimenter phone = 1-775-784-1384; Experimenter fax = 1-775-784-1650; Experimenter department = Dept. of Biochemistry; Experimenter institute = University of Nevada; Experimenter address = MS200; Experimenter address = Reno; Experimenter address = Nevada; Experimenter zip/postal_code = 89557; Experimenter country = USA Experiment Overall Design: 12 samples were used in this experiment
Project description:Hydrogen peroxide (H2O2) can act as a signaling molecule that influences various aspects of plant growth and development, including stress signaling and cell death. Catalase deficient plants are pioneering systems which accumulate hydrogen peroxide (H2O2) from peroxisomal origin during photorespiratory challenges. Respiratory burst oxidase homologues D and F are known to participate in intracellular oxidative stress response launched in cat2 mutants (Chaouch et al., 2012). We studied the compared the transcriptional response of cat2 rbohD and cat2 rbohF double mutants versus the cat2 background to further adress their role during photorespiratory stress.
Project description:To identify genes that regulate root development in a hydrogen peroxide devendent manner, we performed a time course microarray analysis of root treated with 1mM H2O2.
Project description:Oxidative stress due to endogenous hydrogen peroxide production by Lactobacillus species is a well-known issue in the food industry. In this study, the transcriptional response to oxygen of Lactobacillus johnsonii, one of the H2O2-producing strains used in the food industry, was analyzed. It was found that aerobic growth conditions led to a more than two-fold downregulation of 45 genes as compared to anaerobic growth, whereas 6 genes were more than twofold upregulated. Among the upregulated genes were two genes that displayed significant homology to NADH-dependent oxidoreductase (NOX). The postulated transcriptional regulation of the nox promoter by oxygen was studied using a GUS-reporter construct, confirming a 2.1-fold upregulated GUS-expression upon aerobic growth. Exposure to sublethal levels of hydrogen peroxide did not result in significant regulation of the nox promoter. In a previous study of hydrogen peroxide production by L. johnsonii, a NADH flavin reductase (NFR) was identified to be involved in hydrogen peroxide production. An NFR-deficient derivative was strongly impaired in H2O2 production, but regained a partial H2O2 producing capacity upon prolonged oxygen exposure. The nox-promoter appeared to be 3.6-fold upregulated under aerobic conditions in the NFR-deficient background, which may imply a role of this gene in the regained H2O2 production. Indeed, deletion of the nox-gene in the NFR-deletion background, resulted in a strain that no longer produced H2O2, also during prolonged exposure to oxygen. The double-mutant (nfr, nox) displayed strongly impaired aerobic growth and oxygenation induced rapid growth stagnation that is not caused by H2O2. We conclude that H2O2 production in L. johnsonii is primarily dependent on NFR but can also involve an oxygen-inducible NADH oxidase under aerobic conditions. Moreover, our results imply that H2O2 production plays a prominent role in oxygen tolerance of L. johnsonii.
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:ChIP-seq analysis was conducted to investigate the effects of hydrogen peroxide (H2O2) treatment on the occupancy of MLL1 and UTX, and the associated histone modifications in HaCaT cells.