STRUCTURE AND FUNCTION OF THE PHOTOSENSOR PHYTOCHROME

植物具有高度灵敏的光敏传感器光敏色素。红色 波长光被光传感器分子的Pr形式感知， 它被光化学转化为PFR形式。然后是后者 在植物中触发两种类型的细胞信号转导，一种 涉及到几个基因的表达，这些基因在 黑暗和另一种涉及细胞器运动和 形态/昼夜节律，如开花等。 可通过远红波长光还原为Pr形式。 植物体介导的光信号响应的分子机制 在植物中的作用仍未完全阐明。长期目标 因此，拟议的研究的目的是了解 光敏色素在结构-机械水平上的作用。我们的特定 这项研究的目的是阐明其结构和功能 植物光致变色光传感器与模型的关系 例如原生质体之类的系统。因为基因的调节作用和 光敏色素介导的光敏转导过程可能 显示出与荷尔蒙基因有用的对比和/或相似性 动物的调节和感觉转导(如视觉)， 拟议中的研究在生物医学上与增进我们的理解有关 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.