STRUCTURE AND FUNCTION OF THE PHOTOSENSOR PHYTOCHROME

植物具有高度敏感的光敏色素。 红色 波长光被Pr形式的光传感器分子感知， 其被光化学转化为Pfr形式。 后者然后 在植物中触发两种类型的细胞信号传导， 涉及在细胞中转录的几个基因的表达， 黑暗和另一个涉及细胞器运动， 形态/昼夜节律，如开花等。 可以通过远红波长的光恢复到Pr形式。 光敏色素介导光信号反应的分子机制 在植物中的作用还没有完全阐明。 长期目标 因此，这项研究的目的是了解 光敏色素在结构-机制水平上的作用。 我们的具体 本研究的目的是阐明 植物与模型中光致变色光感受器的关系 系统如原生质体。 由于基因的调节作用和 光敏色素介导的感光传导过程可能 揭示了与激素基因的有用对比和/或相似性 调节和感觉传导（例如视觉）， 拟议的研究在生物医学上相关，以提高我们的理解， 调节生物学和感觉生理学的基本原理。

Plants possess a highly sensitive photosensor phytochrome. Red wavelength light is perceived by the Pr form of photosensor molecule, which is photochemically converted to the Pfr form. The latter then triggers two types of cellular signal transduction in plants, one involving expression of several genes that are nt transcribed in the dark and another involving organelle movement and morphological/circadian rhythms such as flowering, etc. The Pfr form can be reverted to the Pr form by far-red wavelength light. The molecular mechanism of the phytocrome-mediated photosignal responses in plants still has not been fully elucidated. The long term objective of the proposed study is, therefore, is to understand the mechanisms of phytochrome action at the structural-mechanistic level. Our specific aim of the proposed research is to elucidate the structure-function relationship of the photochromic light sensor in plants and in model systems such as protoplasts. Since the gene regulatory role and the photosensory transduction process mediated by phytochrome are likely to reveal a useful contrast and/or similarity to the hormonal gene regulation and sensory transduction (e.g.m vision) in animals, the proposed study is biomedically relevant in enhancing our understanding of the basic principles of regulatory biology and sensory physiology.