Signal Transduction in Plant Guard Cells

植物保护细胞将用于研究植物膜信号转导的细胞过程。保护细胞将环境刺激转化为与质子泵活性相关的胀压变化。该项目将研究电致泵介导保护细胞对光和植物激素等刺激反应的机制。使用膜片钳技术的电生理学方法将用于测量原生质体和液泡中的电泵电流。荧光探针结合视频成像技术将用于检查伴随质子泵送的内部pH值的变化。研究将集中于研究：1)红色和蓝色光接受对质子泵电流的控制，2)脱落酸和吲哚乙酸等植物激素对电致泵电流的影响，3)细胞质因子对质子泵电流的调节，4)质子泵刺激引起的内部pH变化，5)液泡膜中质子泵电流的性质。本研究将利用电生理学和荧光探针技术，结合光学显微镜的视频成像技术，为植物膜将环境信号转化为细胞反应的机制，以及钙和pH在信号转导事件链中所起的作用提供基础的新信息。

Plant guard cells will be used to study cellular processes underlying signal transduction in plant membranes. Guard cells transduce environmental stimuli into changes in turgor pressure associated with proton pump activity. This project will examine mechanisms by which electrogenic pumps mediate guard cell responses to stimuli such as light and plant hormones. Electrophysiological approaches using the patch clamp technique will be used to measure electrogenic pump currents in protoplasts and vacuoles. Fluorescent probes in conjunction with video imaging techniques will be used to examine changes in internal pH that accompany proton pumping. Research will focus on the study of: 1) the control of proton pump currents by red and blue photoreception, 2) effects of plant hormones such as abscisic acid and indole acetic acid on electrogenic pump currents, 3) regulation of proton pump currents by cytoplasmic factors, 4) changes in internal pH that accompany stimulation of proton-pumping, and 5) the properties of proton pump currents in the vacuolar membrane. This research will use techniques of electrophysiology and fluorescent probes in combination with video imaging techniques for the light microscope to provide fundamental new information on the mechanisms by which plant membranes transduce environmental signals into cellular responses, and on the role played by calcium and pH in the chain of signal transduction events.