STRUCTURE FUNCTION ANALYSIS OF INFORMATION PROCESSING IN SENSORY SYSTEMS

植物细胞信号转导的分子基础仍然是 大部分未知。 虽然钙离子被认为是第二个 植物细胞信使，胞质钙离子的时空变化 离子对各种环境刺激响应并不好 由于成像技术上的困难而被表征。 我们有 开发了一种新的方法来加载钙指标， 钙绿色-1和indo-1进入植物细胞的细胞质， 气孔保卫细胞 气孔控制气体交换，包括 H2O损失（蒸腾）和CO2吸收。 了解法规 气孔的数量对今后的遗传改良具有重要意义 气体交换 激素脱落酸（阿坝）导致气孔 在脱水条件下关闭。 虽然阿坝信号 途径是未知的，已经提出，增加 胞质CA ~（2+）是最早发现的阿坝信号事件。 使用 一种新开发的将钙指示剂加载到 鸭跖草属保卫细胞和表皮细胞的细胞质 通过对植物体内Ca 2+浓度的时空变化进行监测， 浓度响应阿坝通过使用激光荧光共聚焦 成像技术。 此外，我们还扩展了这种方法， 正在进行分子遗传学研究，以确定ABA是如何诱导 拟南芥阿坝信号突变体中CA 2+的增加受到影响 thaliana. 我们还开发了比率式同焦成像 包括拟南芥在内的植物细胞。 这些研究 允许对克隆的遗传基因座的功能进行细胞分析 拟南芥中阿坝信号的研究。 我们也计划应用这些 其他植物细胞的技术，识别和响应 寡糖激发子，以阐明 植物特异性防御反应信号转导。 我们有 一直在使用共聚焦显微镜和图像分析设施， NCMR，包括在NCMR开发的程序B轨道。

Molecular bases for signal transduction in plant cells are still largely unknown. Though calcium ion was proposed as a second messenger in plant cells, spatio-temporal changes in cytosolic calcium ion in response to various environmental stimuli have not been well characterized due to the technical difficulties in imaging. We have developed a novel method to load the calcium indicators such as calcium green-1 and indo-1 into the cytoplasm of plant cells including stomatal guard cells. Stomatal pores control gas exchange including H2O loss (transpiration) and CO2 uptake. Understanding the regulation of stomatal pores is important for the future genetic improvement of gas exchange. The hormone absisic acid (ABA) causes stomatal pores to close uder dehydrated conditions. Although much of the ABA signaling pathway is unknown, it has been proposed that an increase in cytoplasmic CA2+ is the earlies known ABA signaling event. Using the newly-developed method to load the calcium indicatiors into the cytoplasm of guard cells as well as epidermal cells of Commelina communis, we monitored the spatio-temporal changes in Ca2+ concentration in response to ABA by using laser fluorescence confocal imaging techniques. Furthermore, we have extended this approach and are pursuing molecular genetic studies to determine how ABA-induced CA2+ increases are affected in ABA signaling mutants of Arabidopsis thaliana. We have also developed ratiometric onfocal imaging technique s for plant cells including Arabidopsis. These studies are allowing a cellular analysis of the function of cloned genetic loci for ABA signaling in Arabidopsis. We are also planning to apply these techniques to other plant cells that recognizes and respons to ligosaccharide elicitors to elucidate the molecular mechanisms of signal transduction for plan-specific denfense responses. We have been using the confocal microscopy and image analysis facilites at the NCMIR, including the program B track developed at the NCMIR.