PlDAM-PlSOC1互作调控芍药地下芽生理休眠解除的分子机制研究

“芍药南移”意义显著，但江南暖冬引发芍药地下芽的生理休眠解除发生障碍，无法满足需冷量，严重阻碍了该项事业的推进。研究芽的生理休眠解除机理、培育出低需冷量种质几乎是唯一解决办法。DAM和SOC1被证明是调控多年生植物芽生理休眠的关键基因。前期发现，芍药DAM和SOC1的表达与芽生理休眠解除密切相关。本项目拟选择来自中国南、北地区且芽生理休眠性状差异显著的2个芍药种质，依据SMRT测序获得的全长序列来克隆PlDAM和PlSOC1及其启动子，利用同源沉默检验其调控芽生理休眠解除的功能；通过酵母单杂交、靶基因预测和转录因子筛选等，检测二者在芽生理休眠解除期的互作关系。对比PlDAM和PlSOC1的调控功能、表达特征、启动子结构、直接和间接互作在2个特异性种质间的差异，解析芍药芽生理休眠解除的分子调控机制，为培育生理休眠期短的低需冷量芍药种质提供科学依据；并为相对欠缺的地下芽休眠机理研究补充新成果。

“The southward planting of herbaceous peonies” is a classic scientific problem in the fields of landscape plants and ornamental horticulture. The renaissance of herb peonies’ industry and landscape use in the south regions of the Yangtze river is significant, but has always been hindered by warm winters which lead to serious disorder of the underground-bud endodormancy release and unsatisfied chilling requirement (CR) of herbaceous peonies. Studying the mechanism of bud endodormancy release and then breeding the low-CR germplasm is almost the only solution to solve this obstacle. DAM and SOC1 has been confirmed as the pivotal genes to regulate bud dormancy of perennial plants. Preliminary results showed that the expressions of PlDAM and PlSOC1 are closely related to bud endodormancy release of Paeonia lactiflora Pall. In this project, a pair of distinctive peony cultivars with opposite provenances and contrasting endodormancy traits will be selected as research materials. The full-length PlDAM and PlSOC1 of two cultivars and their promoters will be cloned based on the full-length sequences acquired by the single molecular real time (SMRT) sequencing previously. Functions of these two genes to regulate bud endodormancy release will be validated by silencing in P. lactiflora. The interactions between PlDAM and PlSOC1 will be observed by yeast one-hybrid, target-gene prediction and transcription factor screening. The differences in functions, expression, promoter sequences, direct and indirect interactions of PlDAM and PlSOC1 in two different specific germplasms will be compared to reveal the regulation mechanism of peony’s bud endodormancy release. This project will provide scientific evidences for breeding the low-CR peony germplasms, and enrich new knowledge to the limited mechanism research of underground bud dormancy.