植物UV-B信号通路中关键模块（UVR8-BES1/BIM1）的起源与演化研究

UV-B信号通路的起源是绿色植物演化过程中的关键革新，它在植物适应陆地强烈UV-B辐射、调控植物代谢及生长发育中发挥了重要作用。UVR8是绿色植物特有的UV-B受体，BES1/BIM1是UVR8下游的关键调控元件。UVR8-BES1/BIM1模块是植物传导UV-B信号的核心元件，UV-B辐射能够促进UVR8-BES1/BIM1的结合，实现生长发育调控和UV-B适应。然而，UVR8-BES1/BIM1模块仅在拟南芥中有相关研究，关于该模块的起源及演化研究尚未有报道。本项目拟通过生物信息学和分子生物学相结合的手段，从不同植物类群中获得UVR8、BES1和BIM1的同源序列，进行大尺度的系统发育及分子进化分析；选取绿藻、轮藻和早期陆地植物的代表物种进行功能实验，揭示UVR8-BES1/BIM1模块的起源及在植物适应UV-B辐射中的作用，为深入理解早期陆地植物适应陆生环境的机制提供科学依据。

The origin of UV-B signaling pathway is a key innovation in the evolution of green plants, and it plays vital roles in plant metabolism, growth, developments, and the adaptations to the intense UV-B radiations in terrestrial environments. UVR8 is the plant-specific UV-B photoreceptor, and BES1/BIM1 are the crucial regulators mediated by UVR8. UVR8-BES1/BIM1 module is the core components in plant UV-B signaling pathway, and the UV-B-light-promoted UVR8-BES1/BIM1 interactions can induce UV-B acclimation. The UVR8-BES1/BIM1 signaling pathway has been mainly studied in Arabidopsis thaliana, however, the origin and evolution of this module are largely unknown. In this study, we will obtain the orthologs of UVR8、BES1 and BIM1 using both bioinformatics and cloning approaches from different groups of green plants, and perform phylogenetic and molecular evolutionary analyses. Meanwhile, we will select representatives from chlorophytes, charophytes and early land plants to examine the function of UVR8-BES1/BIM1 module. Our results will reveal the origin and potential roles of UVR8-BES1/BIM1 module in UV-B acclimation, and advance our understanding of the molecular mechanisms underpinning the adaptations of plants to terrestrial environments.