Project description:The involvement the thioredoxin system in radiation resistance was investigated in human lung cancer cells by a combination of ionizing radiation and specific thioredoxin reductase-inhibition by a phosphine gold compound. Gene expression profiles (Human Gene 1.0 ST) of lung cancer cells subjected to ionizing radiation and/or inhibition of thioredoxin reductase were studied. Data analyses were performed using the Affymetrix GeneChip Operating Software (GCOS) Version 1.4.
Project description:af47_thioredoxins - comparison ws vs de and dy - Knock-out mutants of the ferredoxin-thioredoxin reductase were used to evaluate the impact of the redox perturbation of the plastidial thioredoxins on Arabidopsis transcriptome. - Wild-type (WS) and two T-DNA mutant lines for the variable subunit of ferredoxin:thioredoxin reductase ( DY and DE from INRA of Versailles collection) were compared Keywords: wt vs mutant comparison
Project description:Transcriptional profiling of human mesenchymal stem cells comparing normoxic MSCs cells with hypoxic MSCs cells. Hypoxia may inhibit senescence of MSCs during expansion. Goal was to determine the effects of hypoxia on global MSCs gene expression.
Project description:The involvement the thioredoxin system in radiation resistance was investigated in human lung cancer cells by a combination of ionizing radiation and specific thioredoxin reductase-inhibition by a phosphine gold compound.
Project description:The Saccharomyces cerevisiae Yap1p transcription factor is required for the H2O2-dependent activation of many antioxidant genes including the TRX2 gene encoding thioredoxin 2. To identify factors that regulate Yap1p activity, we carried out a genetic screen for mutants that show elevated expression of a TRX2-HIS3 fusion in the absence of H2O2. Two independent mutants isolated in this screen carried mutations in the TRR1 gene encoding thioredoxin reductase. Northern blot and whole-genome expression analysis revealed that the basal expression of most Yap1p targets and many other H2O2-inducible genes is elevated in Deltatrr1 mutants in the absence of external stress. In Deltatrr1 mutants treated with H2O2, the Yap1p targets, as well as genes comprising a general environmental stress response and genes encoding protein-folding chaperones, are hyperinduced. However, despite the elevated expression of genes encoding antioxidant enzymes, Deltatrr1 mutants are extremely sensitive to H2O2. The results suggest that cells lacking thioredoxin reductase have diminished capacity to detoxify oxidants and/or to repair oxidative stress-induced damage and that the thioredoxin system is involved in the redox regulation of Yap1p transcriptional activity.
Project description:Gene methylation profiling of immortalized human mesenchymal stem cells comparing HPV E6/E7-transfected MSCs cells with human telomerase reverse transcriptase (hTERT)- and HPV E6/E7-transfected MSCs. hTERT may increase gene methylation in MSCs. Goal was to determine the effects of different transfected genes on global gene methylation in MSCs.
Project description:The Saccharomyces cerevisiae Yap1p transcription factor is required for the H2O2-dependent activation of many antioxidant genes including the TRX2 gene encoding thioredoxin 2. To identify factors that regulate Yap1p activity, we carried out a genetic screen for mutants that show elevated expression of a TRX2-HIS3 fusion in the absence of H2O2. Two independent mutants isolated in this screen carried mutations in the TRR1 gene encoding thioredoxin reductase. Northern blot and whole-genome expression analysis revealed that the basal expression of most Yap1p targets and many other H2O2-inducible genes is elevated in Deltatrr1 mutants in the absence of external stress. In Deltatrr1 mutants treated with H2O2, the Yap1p targets, as well as genes comprising a general environmental stress response and genes encoding protein-folding chaperones, are hyperinduced. However, despite the elevated expression of genes encoding antioxidant enzymes, Deltatrr1 mutants are extremely sensitive to H2O2. The results suggest that cells lacking thioredoxin reductase have diminished capacity to detoxify oxidants and/or to repair oxidative stress-induced damage and that the thioredoxin system is involved in the redox regulation of Yap1p transcriptional activity. Groups of assays that are related as part of a time series. Using regression correlation
Project description:Transcriptomic study of a thioredoxin reductase knock-out mutant.<br> <br> Biological question :<br> Thioredoxins are small redox proteins implicated in crucial pathways of cell life. They are reduced by a conserved flavoprotein named NADPH-dependent thioredoxin reductase (NTR). In order to give an insight into the functions of the NTR/thioredoxin pathway in Arabidopsis, we have used a reverse genetic approch. Both NTR genes (NTRA and NTRB) have been inactivated in the double ntra ntrb mutant. T-DNA lines have been provided by the SALK library. Surprisingly, this mutant shows a limited phenotype suggested that some additional redox pathways are involved in compensating the inactivation of the NTR/thioredoxin pathway. In order to isolate compensatory genes that would be transcriptionally induced in the ntra ntrb mutant, we have performed this CATMA project.<br> <br> Seeds of the wild-type Col-0 ecotype and of the ntra ntrb homozygote double mutant were sowed in soil. Three replicates of lines were made (Col-0 1, 2 and 3 ntra ntrb 1, 2 and 3) : plants were put at different places of the greenhouse and grown at different times. Germination was synchronized by 4 days at 4C and plants were grown during 17 days, until they reached a 6 rosette leaves stage. Entire plants (30 plants per sample) were harvested, frozen in liquid nitrogen and stored at -80C until extraction.<br> <br>