Project description:Plants often face combinatorial stresses in their natural environment. Here arsenic (As) toxicity was combined with hypoxia (Hpx) in the roots of Arabidopsis thaliana as it often occurs in nature. The present work aimed to explore the effects of single and combined hypoxia and As stress applied at realistic stress levels to hydroponically grown A. thaliana. Arsenic as well as hypoxic growth conditions generate a characteristic signaling pattern, a significant part of which is mediated by ROS. The current study utilized the microarray to determine the overlapping signalling pattern and changes in gene expression for the defined stress combinaton compared to individual stresses. Overall design: Roots of Arabidopsis thaliana (Col-0; WT), grown hydroponically for 32d were exposed to either 250 µM As (AsV; Na2HAsO4) alone or in combination with hypoxic nutrient media and also hypoxia alone. The plant material was harvested after 7d of treatment and root samples were used for RNA extrcation and subsequent hybridization on Affymetrix microarray chips. Three completely independent biological replicates were analyzed for each treatment (C1, C2, C3: Control; As1, As2, As3: Arsenic; Hpx1, 3, 5: Hypoxia; Hpx2, 4, 6: Hypoxia + Arsenic)
Project description:We examined the changes in gene expression in Arabidopsis thaliana grown under arsenate stress. The transcriptional profiling reveals antioxidant activity and repression of the phosphate starvation response. Keywords: dual label, stress response Overall design: This experiment included a comparison of three biological replicate controls against three biological arsenate-stressed replicates with a dye-swap technical replicate for a total of six microarray slide hybridizations.
Project description:Gene expression patterns of the plant colonizing bacterium,Pseudomonas putida KT2440 were evaluated as a function of growth in the Arabidopsis thaliana rhizosphere. Gene expression in rhizosphere grown P. putida cells was compared to gene expression in non-rhizosphere grown cells. Keywords: Gene expression Overall design: The experiment contained three biological replicates, two conditions (plus plant, minus plant), and two time points (48 and 120 hours).