Light, Stomatal Function and Energy Transduction in Guard Cells

气孔调节叶片中的气体交换，从而影响 生产力和植物的水分平衡。 气孔 控制依赖于保卫细胞的感觉传导， 内部和外部刺激，翻译信息， 叶环境中的主要条件，以调制 气孔的大小。 本报告的总体目标 研究计划是了解信号感知， 代谢转导和孔径调节 气孔对光线的反应。 最近的研究 表明光激活了保卫细胞的质子泵 质膜通过两种不同的转导途径， 一个由蓝光感光器激活，另一个由 保卫细胞叶绿体 该提案的目的是详细说明 参与的感觉转导步骤的表征 泵激活。 利用电生理技术 膜片钳、代谢和光生物学两方面的特点 将研究途径，包括临界浓度 ATP和其他辅因子，注量率依赖性，特异性 药理学特性，以及 与保护电池对太阳能的响应有关的两种途径 辐射 蓝光感光器的身份将是 在低温和室温下通过光谱分析研究 温度 完整叶片的气体交换技术 用于将亚细胞和细胞外基质的分辨特征 细胞水平与气孔性能的关系 条件 气孔是叶片表面的气孔， 水和气体进出叶片组织的通道。 通过气孔的适当运输对于植物的生长至关重要。 进行光合作用和维持水分平衡的能力。 气孔的打开和关闭是对环境刺激的反应。 这项研究的结果将增进我们对 调节气孔运动的细胞机制， 更一般地说，将增加基本知识， 植物的感觉传导和离子运输机制 细胞

Stomata regulate gas exchange in leaves, thus affecting productivity and the water balance of the plant. Stomatal control depends on sensory transduction by guard cells of internal and external stimuli, translating information about prevailing conditions in the leaf environment to modulation of the size of stomatal apertures. The overall objective of this research program is to understand the signal perception, metabolic transduction, and aperture regulation during the movements of stomata in response to light. Recent studies have shown that light activates proton pumping at the guard cell plasmalemma via two different transduction pathways, one activated by a blue light photoreceptor and the other by the guard cell chloroplast. The aim of this proposal is the detailed characterization of the sensory transduction steps involved in pump activation. Using the electrophysiological technique of patch clamping, metabolic and photobiological features of the two pathways will be investigated, including critical concentrations of ATP and other cofactors, fluence-rate dependence, specific pharmacological properties, and interactive features between the two pathways in connection with the guard cell response to solar radiation. The identity of the blue light photoreceptor will be investigated by spectroscopic analysis at low and room temperature. Gas exchange techniques with intact leaves will be used to correlate resolved features at the subcellular and cellular level with stomatal performance under physiological conditions. Stomata are pores in the surface of a leaf which regulate the passage of water and gasses into and out of the leaf's tissue. Proper traffic through the stomata is vital for the plant's ability to conduct photosynthesis and maintain its water balance. The stomata open and close in response to environmental stimuli. The results of this research will enhance our understanding of the cellular mechanisms which regulate the movements of stomata, and more generally, will increase basic knowledge of the mechanisms of sensory transduction and ion transport in plant cells.