LEAFY, a plant transcription factor as a model for transcriptional activation by ubiquitination

LEAFY，一种植物转录因子，作为泛素化转录激活的模型

• 批准号: 423452781
• 负责人: Dr. Ulla Dolde, Ph.D.
• 金额: --
• 依托单位: Laboratoire de Recherche en Sciences Végétales
• 依托单位国家: 德国
• 项目类别: Research Fellowships
• 财政年份: 2019
• 资助国家: 德国
• 起止时间: 2018-12-31 至 2021-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/423452781?language=en
• 关键词: LEAFY; plant; transcription; factor; model

Flowers are the most complex structure of flowering plants or angiosperms. Flowers ensure successful reproduction of angiosperms and are the basis for fruit and seed development, which are major food source for humans and animals. The plant-specific transcription factor LEAFY (LFY) is the master regulator of flower development in angiosperms. LFY specifies the emergence of the floral meristem identity and therefore, plays a central role in the developmental switch from vegetative stage (leaves and branches) to reproductive stage (flowers). Recently it has been shown that LFY activity is dependent on the interaction with the F-box protein UNUSUAL FLORAL ORGANS (UFO). UFO is an ubiquitin ligase and it is assumed that UFO is involved in protein degradation. It is known that LFY can trigger the formation of flowers from leaves in conjunction with UFO, but how UFO potentiates LFY activity has remained obscure. Although few examples of transcriptional activation by ubiquitination and possible degradation of transcription factors exist in yeast and mammals, this mechanism has so far not been ascribed to plants. The aim of this project is to unravel the biological role of LFY-UFO interaction in flower development and what the role of ubiquitination pathways is in regard of LFY activity as a test case for activation of transcription by ubiquitination in plants. I plan to investigate the mechanism of the LFY-UFO interaction in conjunction with the ubiquitin-system and to analyse the molecular consequences on target gene expression and flower development using an integrated approach using cell biology, biochemistry, molecular biology, top-notch imaging and proteomics. LFY is the perfect model to investigate this fundamental question in biology, due to its well-known characteristics and functions (structure, DNA binding properties, interacting partners, target genes, etc), as well as available tools. The knowledge gained from my studies will clearly benefit to the understanding of flower development in plants, especially since the LFY-UFO interactions was identified in several flowering plants. Besides, this project will tackle a question of general significance in biology regarding how ubiquitination can activate transcription, therefore being of great interest to communities interested in transcription and ubiquitination in other model organisms.

花是有花植物或被子植物中最复杂的结构。花是被子植物成功繁殖的保证，也是果实和种子发育的基础，而果实和种子是人类和动物的主要食物来源。植物特异性转录因子LEAFY（LFY）是被子植物花发育的主要调控因子。LFY指定花分生组织身份的出现，因此，在从营养阶段（叶和枝）到生殖阶段（花）的发育转换中起着核心作用。最近，它已被证明LFY活动是依赖于与F-盒蛋白不寻常的花器官（UFO）的相互作用。UFO是一种泛素连接酶，它被认为是参与蛋白质降解。人们知道LFY可以与UFO一起触发叶子形成花朵，但UFO如何增强LFY活动仍然不清楚。虽然在酵母和哺乳动物中存在通过泛素化和可能的转录因子降解的转录激活的例子很少，但这种机制迄今尚未归因于植物。该项目的目的是揭示LFY-UFO相互作用在花发育中的生物学作用，以及泛素化途径在LFY活性方面的作用，作为植物中泛素化激活转录的测试案例。我计划研究LFY-UFO相互作用的机制，结合泛素系统，并使用细胞生物学，生物化学，分子生物学，一流的成像和蛋白质组学的综合方法分析目标基因表达和花发育的分子后果。LFY是研究生物学中这一基本问题的完美模型，因为它具有众所周知的特征和功能（结构、DNA结合特性、相互作用伴侣、靶基因等）以及可用的工具。从我的研究中获得的知识显然将有助于理解植物中的花发育，特别是因为LFY-UFO相互作用在几种开花植物中被确定。此外，该项目将解决生物学中具有普遍意义的问题，即泛素化如何激活转录，因此对其他模式生物中的转录和泛素化感兴趣的社区非常感兴趣。