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

许多生活在炎热气候中的多年生植物已经进化到能够在极端高温下生存。 据推测，预计伴随下世纪全球气候变化而出现的5-6摄氏度的温和升温对这些植物的影响很小。然而，关于这种温度升高对在其热存活极限附近生长的植物细胞的影响的研究表明，情况并非如此，并导致了这个项目。植物的生长是通过现有细胞的分裂，然后扩大较小的新形成的细胞。研究表明，温度升高5-6ºC会阻碍一种关键的生长激素-生长素的作用，而生长素在较低温度下会激活植物细胞分裂和生长所需的基因。 在这个项目中，将确定5-6ºC的温度升高是否会阻止生长素激活控制完整植物细胞分裂和生长的基因的能力。 还将研究温度升高是否会通过抑制一种称为Rac GTdR的特定酶来阻断生长素的作用，Rac GTdR是导致生长素激活反应的事件链中的一种重要蛋白质。 更广泛的影响：这项研究将在一个小型本科学院的生物系进行，教师和学生共同参与研究。该项目将鼓励本科生通过以下方式从事研究事业：（1）每年招募和培训两名学生进行研究;（2）开发学生之间的合作研究项目;（3）创建一个以学生为主导的科学阅读小组;以及（4）安排由杰出科学家主持的学生访问，他们将与学生和教师就研究进行咨询。将举行一个区域教师讲习班，主题是将研究纳入本科教学。 这项研究对保护本地耐热植物和可能依赖它们的动物的管理具有意义。 它也可以应用于开发耐热多年生作物和植物的遗传工程策略。

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.