茶树是以幼嫩叶片为利用对象的多年生常绿木本作物。春季萌芽早晚影响茶叶的经济价值和茶树对气温波动的应对能力，一直是茶树品种选育过程中备受关注的重要生物学性状之一。项目组前期研究表明茶树越冬芽休眠解除的早晚是影响春茶发芽期的重要因素，DNA甲基化译码蛋白CsMBD13a介导的主动去甲基化过程在茶树休眠解除调控中发挥核心作用。为深入解析CsMBD13a的作用机制，本项目将在基因序列及表达分析的基础上，利用转基因等技术手段明确基因的功能及启动子响应模式；通过上游转录因子和互作蛋白的全面鉴定揭示CsMBD13a的分子调控机制；开展转基因植株gDNA甲基化水平检测，转录组、全基因组甲基化测序分析，结合休眠解除阶段茶树越冬芽的CHIP-Seq分析发掘CsMBD13a的识别区域和下游调控基因，阐明其在茶树休眠解除中的作用机制。为茶树休眠机理的全面揭示、不同萌发物候茶树品种选育和分子设计育种提供理论支撑。

Tea plant is a perennial evergreen woody species that use fresh leaves as their utilization object. The date of bud break in spring affects the economic value of tea products and the ability of young shoots in coping with temperature fluctuations, which has always been one of the most important biological characteristics in the process of tea variety breeding. Previous studies showed that the dormancy release of tea overwintering buds was an important factor affecting the bud break of tea plant in spring. It was hypothesized that active demethylation mediated by DNA methylation decoding protein CsMBD13a plays a central role in the regulation of dormancy release of tea plants. In order to further understand the role and mechanism of CsMBD13a, this project will perform gene sequence and expression analysis initially, and then use the transgenic technique to clarify gene function and promoter response mode. Moreover, comprehensive identification of upstream transcription factors and interaction proteins will be carried out to reveal the molecular regulation mechanism of CsMBD13a. Furthermore, gDNA methylation level detection, transcriptome analysis, genome-wide methylation sequencing analysis of transgenic plants, combing with CHIP-Seq analysis of overwintering buds of tea plants during dormancy release period, will be performed to identify the recognition regions and downstream regulatory genes of CsMBD13a. Finally, the role and mechanism of CsMBD13a in dormancy release regulation of tea plants will be clarified to improve understanding of bud dormancy and laid a theoretical foundation for the selection and molecular design breeding of tea varieties with different sprouting phenology.