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Byline: Tapas. Sur, Suparna. Chatterjee, Alok. Hazra, Richeek. Pradhan, Supriyo. Chowdhury Objectives: Systematic oral toxicity study for black tea (Camellia sinensis), the most commonly consumed variety of tea, is lacking. [...]

The effect of arsenate with or without phosphate on the growth and metabolism in rice seedlings cv. MTU1010 was studied. In the test, cv. arsenic was more toxic for root growth, than for shoot growth, where root hairs were fewer and short, roots were characteristically stubby, brittle and root tips gradually turned brown. Arsenic caused damage to the root epidermal cells and aerenchymatous cortex. The level of total chlorophyll, chlorophyll-a, chlorophyll-b and fluorescence intensity were decreased in arsenic treated rice seedlings. Arsenic toxicity affected the activities of different antioxidant scavenging enzymes in the test seedlings. Activities of superoxide dismutase and ascorbic acid oxidase were increased, whereas catalase and catechol peroxidase activities were decreased by arsenic application. In these seedlings, the oxidative stress has been observed with arsenic treatments and the level of proline, H2O2 and malondialdehyde contents were increased. Joint application of phosphate with arsenic showed significant alterations on all parameters tested under the purview of arsenic treatment alone leading to better growth and metabolism in rice seedlings. Thus the use of phosphorus enriched fertilizers in arsenic contaminated soil may improve the production of healthy rice plants. [ABSTRACT FROM AUTHOR]

Sequestration of a transcription factor in a cellular membrane and releasing it on demand is an additional layer of gene regulation that is considered a rapid mode to reprogram a gene expression cascade when a plasma membrane stress signal is perceived. Better understanding of the dynamic exchange of membrane-bound transcription factors (MTFs) during biotic stress requires the development of a simple, efficient, and quick assay system. Here we report an Agrobacterium-based transient transformation method to assay the localization of fluorescent protein-tagged MTFs in tomato leaf epidermal peels that are subsequently infected with a pathogenic fungus. Essentially, our method mimics natural infection and facilitates the realistic monitoring of MTF movement during activation of a signaling event.