Project description:We identified a small zinc finger protein, MBS, as a new mediator of singlet oxygen responses in Chlamydomonas and Arabidopsis. MBS is required for induction of singlet oxygen-dependent gene expression and, upon oxidative stress, accumulates in distinct granules in the cytosol of Arabidopsis cells. First, we recorded changes in light stress-regulated gene expression profiles after genetically perturbing MBS function by isolating mutants for the two MBS genes (MBS1 and MBS2) and by overexpression of MBS1 in Arabidopsis thaliana. Then, these light stress-related gene expression profiles were analyzed with respect to genes specifically responding to singlet oxygen and hydrogen peroxide/superoxide. The results indicated that MBS inactivation leads to an impaired response to singlet oxygen signaling under light stress. Knock-out or knock-down of the MBS1 and MBS2 genes and overexpression of MBS1 in Arabidopsis thaliana were compared with the wild type and the flu mutant as controls under light stress. Arabidopsis seedlings of mbs1-1, RNAi-MBS2/mbs1-1, 35S:MBS1, the wild type and the flu mutant were harvested at 0 h and 3 h of light stress (HL, 1000 µE m−2 s−1). Total RNA was extracted and cDNA was hybridized to Affymetrix ATH1 microarrays in three biological replicates.
Project description:In order to elucidate the role of the Arabidopsis thaliana LLM-domain B-GATAs in response to high light intensities, a transcriptomic analysis of Col-0, a hexuple LLM-domain B-GATA mutant hex (gnc gnl gata15 gata16 gata17 gata17l) and GNLox under high-ligh stress conditions was performed.
Project description:In response to WRKY40 and WRKY60 perturbation (and high light stress), significant transcriptional re-programming occurs particularly for genes encoding stress responsive mitochondrial and choloplast proteins. We used microarrays to analyse the response to WRKY40 and WRKY63 KO/OE in resonse to high light stress. Wild-type (Col0) and transgenic WRKY40 and WRKY60 knock-out/over-expressing Arabidopsis plants were grown to 21-days and leaf samples were collected with/without high light treatment.
Project description:HSC70 is the cytosolic isoform of plant HSP70. We have found that HSC70 family proteins bind to the heat shock transcription factor A1s (HsfA1s), which are the master regulators of the heat shock response in plants, and suppress their activity. We additionally found that the triple knock out of HSC70s alters responses of Arabidopsis plants to salt stress. To investigate the role of the HSC70s in salt stress responses, we evaluated the effects of the triple knock out on the transcriptome under salt stress.
