Intellectual Merit: Sensing environmental changes and initiating an adequate response is critical for a plant's survival. Previous exposure to a stress can make a plant more resistant to future exposures by producing faster and/or stronger reactions to the stress. Altered responses imply that plants exercise a form of "memory" from a previous stress suggesting that plants could be "trained" to withstand future stresses. However, the mechanisms involved in plant stress memory are unknown leaving a fundamental biological question unanswered. The goals of this project are to examine whether repetitive dehydration stress causes altered responses indicative of plant's "stress memory" and to reveal factors involved in the mechanism. The specific aims are: 1) To analyze the plant's transcriptional and physiological responses to multiple dehydration stress treatments with the purpose of identifying the subset of trainable genes; 2) To identify genes demonstrating epigenetic memory by identifying trainable genes with persistently high levels of epigenetic marks; 3) To examine the roles of the ATX1 chromatin modifying protein and the hormone Abscisic Acid (ABA) in dehydration stress memory and training. Results from this study may broadly impact research on other types of plant stresses. A long term practical goal is to enhance the ability to generate crops that can better withstand recurring patterns of drought spells. This should be a fruitful area for future research both in terms of new science and in terms of applied value.
Broader Impacts: The proposed activities will positively impact human resource development through the direct training of scientists at the undergraduate, graduate and postgraduate level. Schools in rural Nebraska supply classes and laboratories with enthusiastic and motivated undergraduate students. The project will emphasize recruitment of students from underrepresented groups and encourage them to consider a career in biology. To further integrate research with education, undergraduate students will be engaged in small individual bioinformatics research projects, and week-long summer workshops will be organized for students from small liberal arts colleges. Also, the project will continue to be involved with University outreach programs for science teachers from the Lincoln high schools with the goal of acquainting them with cutting-edge genome/epigenome analyses and technologies.