Long-Term Goal and Background: The long-term goal of this research project is to facilitate the assignment of function to every gene in Arabidopsis thaliana. To date, the function of the proteins encoded by more than 20% of plant genes is completely unknown, with the function of up to 43% of these proteins poorly characterized. The specific focus of this research is genes of unknown function and the networks that respond to environmental stress, such as chilling, drought, salt, flooding, high light, and oxidative environments. Environmental stress is the primary cause of crop loss world-wide. A plant's survival and growth is dependent on its ability to cope with environmental stresses. It is clear that a plant's stress response results from a complex set of changes in gene networks and metabolism. While 1000s of genes have been linked to stress networks, in only a few cases have their biochemical and genetic functions been elucidated. In fact, most of the stress-regulated genes identified to date have completely unknown function(s). Specific Aims and Expected Outcome: 1. Determine the change in stress tolerance for > 1,600 plant lines with a disrupted expression of genes of unknown function. The approach is to test plant lines for resistance or susceptibility to stresses including water deficit, salt, high light, heat, chilling, freezing, anaerobiosis, heavy metal and oxidative stress. The primary goal is to begin a systematic approach to evaluate the contribution of all Arabidopsis genes to stress tolerance. Expected outcome: Assigning a putative function to > 1,600 genes with an unknown function. 2. Determine the relationship of genes of unknown function within a global protein-protein interaction network. The approach is to determine > 20,000 examples of protein-protein interactions using a random yeast two-hybrid screening strategy. The primary goal is to uncover links between genes of known and unknown function. Expected outcome: A protein-protein map for Arabidopsis. 3. Over-express > 150 selected genes of unknown function in plants, test transgenic plants for changes in stress tolerance, and search for interacting protein partners. The hypothesis to be tested for each gene is that its over-expression can alter a particular stress response. Expected outcome: Identifying proteins of unknown function with a central importance in stress response and their protein partners. 4. Profile changes in gene expression in > 20 stress-response mutants grown under at least two different stress conditions. The primary goal is to begin creating a network of gene expression changes that can help better focus in-depth experiments on enzymes and regulators of potential importance to environmental stress. Expected outcome: Identifying gene networks involved in environmental stress. 5. Coordinate a centralized website for information on genes of unknown function ("unknowns") from Arabidopsis and provide outreach and training activities for those under privileged and underrepresented in science, on the role of science in agriculture, the environment, and human health. Web-based resources will be established to disseminate unpublished information and link annotation and data to all Arabidopsis "unknowns". All plant lines and results of the project will be released to the academic community on a biannual basis. Expected outcome: A centralized website to enhance research on genes with unknown function. Broader Impacts: The two key "Broader Impacts" of the proposed research are: 1) development and maintenance of a centralized website for information on Arabidopsis genes of unknown function. This site will track and disseminate information on homozygous T-DNA insertion lines for "unknown" genes and their phenotypes, and provide gene structure, gene annotation, protein interaction and mRNA profiling data. 2) Educational outreach for K-12 and interdisciplinary training to postdoctoral, graduate and undergraduates trainees. A summer outreach workshop will teach high school students about Mendelian inheritance in Arabidopsis, the role of science in agriculture, the environment, and human health. This laboratory-based internship program will provide self-confidence building experiences and expose the students to laboratories and scientists. Both undergraduate and K-12 outreach and training activities will target the under privileged and underrepresented in science