Ultrafast Omics Reveals Key Players in the Response of Plants to Abiotic Stress
The long-term goal of this project is to determine how ultrafast alterations in the metabolome and transcriptome of Arabidopsis in response to abiotic stress set the stage for signal transduction events that orchestrate the activation of acclimation responses. Our approach is to identify different metabolites, RNA molecules and pathways that respond to abiotic stress within 10-300 sec and determine how these responses are communicated between cells and impact plant acclimation using an integrated approach of functional genetics, physiology, advanced MS, imaging and bioinformatics.
Changes in environmental conditions such as temperature or light intensity are likely to cause immediate alterations in the level, composition and/or structure of different metabolites, proteins or RNA molecules that precede any known signal transduction or acclimation events in plants. These could occur within seconds of the change in environmental parameters and result from changes in membrane properties, differential enzymatic co-efficiencies, RNA processing, or metabolite and RNA stability. Although much is known about the different signaling and downstream pathways that mediate plant acclimation to stress, virtually nothing is known about the rapid changes in the metabolome and transcriptome of plants that occur within seconds or minutes of abiotic stress initiation. Recent studies from our laboratory identified over 600 transcripts, 50 metabolites and 30 putative new Arabidopsis genes that respond to abiotic stress within seconds. Some of these responses occurred at the affected tissue as well as in tissues that were not directly subjected to stress and included metabolites and transcripts with important function in abiotic stress tolerance. Interestingly, many of these ultrafast responses were altered in mutants impaired in reactive oxygen signaling, which were more susceptible to stress, indicating that reactive oxygen species, ultrafast responses and plant acclimation are intimately linked. We hypothesize that ultrafast alterations in the metabolome and transcriptome of Arabidopsis set the stage for signal transduction events that orchestrate the activation of acclimation responses to environmental stresses and impact plant acclimation.
Our specific aims are:
- Identify metabolites, transcripts and pathways that respond to abiotic stress within 10-300 sec and determine how these responses are communicated among different cells in the affected tissue.
- Determine how ultrafast responses to abiotic stress are communicated between plant tissues subjected to stress and the rest of the plant.
- Use mutants impaired in ultrafast molecular pathways to determine their role in plant acclimation.
This project will highlight an unknown aspect of the plant abiotic stress response, namely ultrafast metabolic and transcriptomic responses to stress. This could have a dramatic and transformative impact on the way we view and understand abiotic stress and its effects on plant metabolism. Results obtained from this study could lead to the development of new and novel approaches to enhance the tolerance of crops to local and/or global climatic changes using pathways and compounds that were not previously considered or known. The proposed study could also identify novel antioxidants and other compounds that function to reduce the effects of stress on cellular function. These could have a significant impact on many different biochemical and medical fields.
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