NASA/NSF Collaborative Research: Evaluating Phytohormone Signal Transduction Using Xenopus oocytes

9416035 Sutton拟议研究的长期目标是确定与植物对环境刺激的反应有关的信号转导组件。利用非洲爪哇卵母细胞/mRNA注射系统，拟议的研究将集中在高等植物响应低温非冰冻温度和脱水等环境刺激的信号转导。这两种刺激对植物的共同作用是调节内源脱落酸(ABA)水平，并不是所有对低温的反应都依赖于ABA。ABA的作用模式尚未得到确凿的证明。关于ABA受体和第二信使(如果有的话)的实际位置仍然存在疑问，这是信号转导所必需的。拟议的研究最初将集中在ABA上，因为文献中有证据表明ABA刺激钙释放。本实验室的初步数据表明，ABA可能与质膜受体相互作用，导致细胞内钙的增加。这项建议的具体目的是：1)研究注射烟草mRNA的卵母细胞对ABA及其类似物的反应。2)如果钙被动员，定位其来源，试图确定ABA及其受体的功能方式。如果没有动员钙，以确定ABA正在利用的替代第二信使系统。3)利用非洲爪哇卵母细胞系统分离和鉴定ABA受体基因克隆。了解脱落酸和受体(S)如何相互作用将有助于理解植物对低温和脱水刺激的共同反应。建议的研究将涉及电生理学、分子生物学、生物化学和细胞生物学等领域。这项研究的综合性将使研究能够在适当的合作研究实验室进行，并将被证明是一个有益的和令人兴奋的环境，用于培训博士后助理和研究生。***

9416035 Sutton The long-term objective of the proposed research is to identify signal transduction components involved in plant response to environmental stimuli. Using the Xenopus oocyte/mRNA injection system, research proposed will focus on signal transduction in response to the environmental stimuli of low non-freezing temperature and dehydration in higher plants. A common effect of these two stimuli on plants is to modulate endogenous abscisic acid (ABA) levels, not all responses to low temperature are ABA dependent. The mode of action of ABA has not been conclusively demonstrated. Questions remain regarding actual location of ABA receptors, and second messengers, if any, that are necessary for signal transduction. Research proposed will initially focus on ABA, since there is evidence in the literature of ABA stimulating Ca release. Preliminary data from this lab suggests that ABA may interact with plasma membrane receptors and cause an increase in intracellular Ca. Specific aims of this proposal are: 1) To characterize the responses, to ABA and several ABA analogues, from oocytes injected with tobacco mRNA. 2) If Ca is mobilized, to localize its source in an attempt to determine the manner in which ABA and its receptors are functioning. If Ca is not mobilized, to determine the alternative second messenger system being utilized by ABA. 3) To utilize the Xenopus oocyte system to isolate and characterize ABA receptors cDNA clones. Knowing how ABA and receptor(s) interact will help in understanding plant responses common to the stimuli of low temperature and dehydration. Research proposed will involve the areas of electrophysiology, molecular biology, biochemistry and cell biology. The integrative nature of this research will make it possible for research to be performed at appropriate collaborative research laboratories and will prove to be a rewarding and exciting environment for training of postdoctoral associates and graduate students. ** *