Submitted to: American Society of Plant Biologists Annual Meeting
Publication Type: Abstract Only
Publication Acceptance Date: 5/24/2004
Publication Date: 7/24/2004
Citation: Li, L., Lyi, S.M. 2004. Transcriptome changes in response to selenium in arabidopsis thaliana [abstract]. American Society of Plant Biologists Annual Meeting. p.76-77.
Technical Abstract: In plants, selenium is metabolized using a sulfur assimilation pathway. To obtain a complete inventory of genes and pathways that are responsive to selenium and to identify the potential important or novel genes in regulating selenium metabolism, global expression profiling in Arabidopsis in response to selenium treatment was examined. The Affymetrix ATH1 chips that contain approximately 90% of the estimated genes in the total Arabidopsis genome were used. Arabidopsis plants grown hydroponically in modified Johnson nutrient solution for 4 weeks were treated with 10 uM Na2SeO4 for 30 min and 24 hours. The plants were analyzed for concentrations of selenium, sulfate and the other minerals. Transcriptome analysis revealed that 391 genes were altered in expression with a greater than 2-fold change over control, and the majority of these genes responded to selenium treatment at 30 min time point. Among these selenium-responsive genes, 217 genes responded specifically to selenium. As expected, genes involved in sulfate uptake and metabolism (e.g. a high-affinity sulfate transporter, adenosine-5-phosphosulfate-kinase, and S-adenosylmethionine methyltransferase) were induced by selenium. In addition, genes involved in various sulfur-related pathways were also induced. A significant number of calcium-regulated genes were identified. Among the most highly induced genes, two transcription factors that appear to be specific to selenium were found at 30 min of treatment, and various inter-cellular transporters were up-regulated at 24 hours. Knockouts of several potential important genes that may be involved in early signaling transduction processes and selenium metabolism are under study.