GENETIC DISSECTION OF PHYTOCHROME B SIGNALLING

PHYTOCHROME B 信号传导的基因剖析

• 批准号: 2415299
• 负责人: JASON W REED
• 金额: $ 9.87万
• 依托单位: UNIV OF NORTH CAROLINA CHAPEL HILL
• 依托单位国家: 美国
• 财政年份: 1995
• 资助国家: 美国
• 起止时间: 1995-05-01 至 2000-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2415299
• 关键词: Arabidopsis; biological signal transduction; molecular cloning; nonvisual photoreceptor; plant genetics; plant growth /development; plant physiology; pollen; temperature sensitive mutant

DESCRIPTION (Adapted from Applicant's Abstract): When subjected to variation in temperature, light, wind, or humidity, plants alter their physiology and development. Environmental conditions influence commitment to developmental events such as seed germination and flowering, as well as adjustments of growth leading to morphological variation, such as stem elongation, lateral bud inhibition (apical dominance), and leaf size. This plasticity of plant growth and form enables one to learn about the mechanisms of plant development by studying signal transduction pathways that link environmental signals to developmental responses. This proposal describes experiments designed to elucidate molecular mechanisms of light signal transduction. Light influences virtually all aspects of plant development, through signalling system distinct from the photosynthetic apparatus. These systems respond to far-red, red, blue, or UV light through the action of distinct photoreceptors. Mutations in the PHYB gene, encoding the red/far-red photoreceptor phytochrome B, cause several developmental phenotypes including elongated hypocotyls, early flowering, and increased apical dominance. Characterization of more phyB mutations will provide information on structural requirements for phytochrome B function. Screens for mutations that suppress or enhance the long hypocotyl phenotype of a phyB mutant will identify genes whose products function downstream in phytochrome B signal transduction, and possibly, in other light signalling pathways. Genetic and physiological experiments will reveal the roles of genes identified by the mutations in control of development by light. Map-based cloning of the most interesting loci will permit molecular reconstruction of the pathways controlling plant developmental responses to the environment. Understanding these mechanisms may allow more rational manipulation of agronomically important traits such as flowering, seed, germination, and height in crop plants, contributing to improvement in human nutrition. These experiments will also lead to fuller insight into basic mechanisms of plant growth.

描述（改编自申请人的摘要）：当经受 在温度、光线、风或湿度的变化中，植物会改变它们的 生理和发育。 环境条件影响 对种子发芽等发育事件的承诺， 开花，以及生长的调整，导致形态 变异，如茎伸长、侧芽抑制（顶端 优势度）和叶片大小。 这种植物生长和形态的可塑性 使人们能够了解植物发育的机制， 研究将环境信号与 发展反应。 该提案描述了设计的实验 阐明光信号转导的分子机制。 光 几乎影响植物发育的所有方面， 不同于光合器官的信号系统。 这些 系统响应远红，红，蓝，或紫外光通过行动 不同的光感受器。 PHYB基因的突变，编码 红/远红光感受器光敏色素B，引起几种发育 表型包括伸长的下胚轴，早花，和 增加顶端优势。 更多phyB突变的表征 将提供光敏色素B结构要求的信息 功能 筛选抑制或增强长 phyB突变体的下胚轴表型将鉴定其产物 在光敏色素B信号转导的下游起作用，并且可能， 在其他光信号通路中。 遗传和生理 实验将揭示由突变确定的基因的作用， 通过光来控制发展。 基于地图的克隆 有趣的基因座将允许分子重建的途径， 控制植物对环境的发育反应。 了解这些机制可能会使更合理的操纵， 农艺学上重要的性状，如开花、种子、发芽，以及 作物的高度，有助于改善人类营养。 这些实验也将导致对基本机制的更全面的了解 指植物生长。