Molecular and Genetic Dissection of Ultraviolet-B Signaling in Arabidopsis

拟南芥中 UV-B 信号传导的分子和遗传解析

• 批准号: 8017840
• 负责人: Zheng-Hui HE
• 金额: $ 23.03万
• 依托单位: SAN FRANCISCO STATE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-03-01 至 2014-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8017840
• 关键词: Agriculture; Animals; Arabidopsis; Biochemical; Biological; Carcinogens; Cataract; Cells; Cloning; DNA Damage; Depressed mood; Development; Dissection; Employee Strikes; Environment; Environmental Risk Factor; Eye; Genetic; Goals; Growth; Health; Human; Immune system; Learning; Light; Malignant Neoplasms; Malignant neoplasm of prostate; Maps; Mediating; Molecular; Molecular Genetics; Nature; Organism; Pathway interactions; Perception; Phenotype; Photosynthesis; Physiological; Plants; Play; Proteins; Receptor Signaling; Recommendation; Reporting; Role; Signal Pathway; Signal Transduction; Skin Cancer; Solar Energy; Suppressor Genes; Testing; The Sun; Vitamin D; Work; innovation; mutant; receptor; response; ultraviolet

DESCRIPTION (provided by applicant): All sun-exposed organisms have to encounter ultraviolet-B (UV-B, 280-320 nm), an integral part of solar radiation. Depending on its energy levels, UV-B can be harmful or beneficial to biological organisms. High- level UV-B causes direct harms including DNA damage, eye cataracts, skin cancer, and immune system suppression in animals, as well as retarded growth and depressed photosynthesis in plants. On the other hand, low-level UV-B can provide beneficial effects including serving as developmental signals in plants and aiding vitamin D synthesis in human. Opposing effects of UV-B on human cancers have also been reported. While UV-B is a known carcinogen that causes skin cancer, it can help suppress prostate cancer development. The damaging effects of high-level UV-B have been intensively studied in many organisms, but little is known about the molecular mechanism of how cells sense low-level UV-B and transduce its specific signals. Low-level UV-B perception and signaling are well-documented physiological phenomena in plants, but the molecular nature of the involved UV-B-specific receptor(s) remains elusive. Understanding the molecular mechanism of how cells sense and respond to UV-B at all levels is fundamentally important to both agriculture and human health. It has been difficult to genetically pin down a specific pathway that is activated by low-level UV-B because of the lack of unambiguous screenable phenotypes specifically associated with low-level UV-B. We have identified an Arabidopsis mutant, rus1 that is specifically hypersensitive to low- level UV-B. The striking phenotypes and extreme UV-B sensitivities of rus1 provide a feasible platform to identify genetic components that can be good candidates for UV-B specific receptors and signaling components. Our long-term goal is to delineate the molecular mechanism of low-level UV-B signaling in Arabidopsis. Our objective in this application is to characterize signaling components that genetically and biochemically interact with RUS1. Our central hypothesis is that RUS1 and its partners function as key players in low-level UV-B perception. We propose the following two specific aims: Aim 1: Characterize specific UV-B signaling components by mapping and cloning extragenic rus1 suppressor genes; Aim 2: Investigate functional roles of RUS1-interacting proteins in UV-B signaling. These studies are innovative in that the dissection of the UV-B signaling pathway would provide vital information of how cells sense and respond to low-level UV-B. At the completion of these studies we expect to know the molecular mechanism of how RUS1 works with other components to respond to environmental low-level UV-B. The successful completion of these studies will help bring a more profound understanding of how cells sense and respond to UV-B at different levels and what is learned can be ultimately used to develop enhanced agricultural practices and better health recommendations for both animals and human. PUBLIC HEALTH RELEVANCE: Ultraviolet-B, an unavoidable environmental factor, can be either harmful as a human carcinogen or beneficial as a prostate cancer suppressor. While much is known about the damaging effect of high-level UV-B, little is known about the molecular mechanism of how cells can be benefited by perceiving low-level UV-B. Our contribution here is to be a detailed molecular understanding of how Arabidopsis cells sense and respond to low-level UV-B. This contribution can be ultimately used to develop better health recommendations and enhanced agricultural practices.

描述（由申请人提供）：所有暴露的生物都必须遇到紫外线-B（UV-B，280-320 nm），这是太阳辐射的组成部分。根据其能量水平，UV-B可能对生物生物有害或有益。高级UV-B会导致直接危害，包括DNA损伤，眼睛白内障，皮肤癌和动物的免疫系统抑制，以及植物中迟滞的生长和光合作用。另一方面，低级UV-B可以提供有益的效果，包括作为植物中的发育信号和帮助人类的维生素D合成。还报道了UV-B对人类癌症的相反影响。虽然UV-B是导致皮肤癌的已知致癌物，但它可以帮助抑制前列腺癌的发展。在许多生物体中，对高级UV-B的破坏作用进行了深入研究，但是对于细胞如何感觉到低水平UV-B并传递其特定信号的分子机制知之甚少。低水平的UV-B感知和信号传导是植物中有据可查的生理现象，但是所涉及的UV-B特异性受体的分子特性仍然难以捉摸。了解细胞如何在各个级别感知和响应UV-B的分子机制对农业和人类健康都至关重要。由于缺乏与低级UV-B相关的明确筛选表型，因此很难将基因固定在被低级UV-B激活的特定途径上。我们已经确定了一种对低水平UV-B的高度敏感的拟南芥突变体Rus1。 RUS1的引人注目的表型和极端的UV-B敏感性提供了一个可行的平台，以识别遗传成分，这些遗传成分可能是UV-B特异性受体和信号传导成分的良好候选者。我们的长期目标是描绘拟南芥中低级UV-B信号传导的分子机制。我们在此应用中的目的是表征遗传和生化与RUS1相互作用的信号传导成分。我们的中心假设是Rus1及其合作伙伴在低级UV-B感知中起着关键参与者的作用。我们提出以下两个特定目的：目标1：通过映射和克隆基因外RUS1抑制基因来表征特定的UV-B信号成分； AIM 2：研究RUS1相互作用蛋白在UV-B信号传导中的功能作用。这些研究具有创新性，因为对UV-B信号通路的解剖会提供至关重要的信息，以了解细胞的感知和对低水平UV-B的反应。这些研究完成时，我们希望知道RUS1如何与其他组件一起工作的分子机制，以对环境低水平的UV-B响应。这些研究的成功完成将有助于更深刻地了解细胞如何在不同层面上感知和对UV-B的反应，最终可以使用所学的知识来开发增强的农业实践，并为动物和人类提供更好的健康建议。 公共卫生相关性：紫外线B（不可避免的环境因素）可能是人类致癌物的有害，或者作为前列腺癌抑制剂有益。尽管对高级UV-B的破坏作用有很多了解，但对于如何通过感知低级UV-B而受益的细胞的分子机制知之甚少。我们在这里的贡献是对拟南芥细胞如何感知和对低水平UV-B的响应的详细分子理解。这项贡献最终可用于制定更好的健康建议并增强农业实践。