LiT: RUI: Effects of Heat Stress on Hormonal Signaling in a Thermotolerant Equatorial Perennial Plant, Nicotiana Glauca (Graham)

Willamette University, Salem OR

Investigators

Abstract

Many perennial plants that live in hot climates have evolved to survive heat extremes. It is assumed that the seemingly modest temperature increases of 5-6ºC predicted to accompany the next century of global climate change will have little effect on these plants. However, research on the effects of such temperature increases on plant cells growing near their thermal survival limits suggests otherwise, and has led to this project. Plants grow by the division of existing cells, and then enlarging the smaller, newly-formed cells. It has been shown that 5-6ºC temperature increases block the action of a critical growth hormone, auxin, that at lower temperatures activates genes required for plant cells to divide and grow. In this project it will be determined whether 5-6ºC temperature increases block auxin's ability to activate genes that control cell division and growth in intact plants. It will also be examined whether temperature increases block auxin action by inhibiting one particular enzyme called a Rac GTPase, an important protein in the chain of events that leads to the auxin-activated responses. Broader Impacts: This research will be conducted in the biology department of a small undergraduate college in which faculty members and students participate together in research. This project will encourage undergraduates to pursue research careers by: (1) recruiting and training two students each year to conduct research; (2) developing collaborative research projects between students; (3) creating a student-led science reading group; and (4) arranging student-hosted visits by prominent scientists who will consult with students and faculty on research. A regional faculty workshop will be held on the topic of integrating research into undergraduate teaching. This study has implications for conservation management of native, heat-tolerant plants and the animals that may depend on them. It may also find application in the development of strategies to genetically engineer heat-tolerant perennial crops and ornamentals.