杜鹃花是世界著名的园林用观赏灌木，品种繁多，但我国园林绿化常用品种却十分单一。低温是限制杜鹃花品种在我国广泛应用的主要因素。对不同杜鹃花品种冬季耐寒性观测中，我们筛选出耐寒品种‘埃尔西·李’，通过分析其冷驯化前后转录组数据，找到差异表达显著的R2R3型MYBs基因。本研究拟通过对杜鹃花MYBs基因的全长克隆和比对分析，确定其类型、序列特性、亚细胞定位和转录激活活性；分析不同耐寒性品种中冷驯化和正常生长条件下，MYBs基因的表达模式；通过转化拟南芥进行表型分析和功能鉴定；转化杜鹃花后，利用ChIP-seq筛选下游靶基因，并在体内和体外对其启动子序列与MYBs转录因子的结合性进行验证；检测靶基因在杜鹃花冷驯化中的表达量变化。综合以上分析，探讨MYBs参与杜鹃花冷驯化提高植物耐寒性的分子调控机制。该研究不仅能丰富MYB转录因子调控冷胁迫响应的理论基础，还可以为选育耐寒杜鹃花种质提供分子参考。

Rhododendron spp. are one of the most famous ornamental shrubs in the world with a large variety of cultivars. However, cultivars commonly used in landscaping in China are limited. Low temperature is the main factor limiting the wide application of rhododendrons in China. From the screening of freezing tolerance in different rhododendrons cultivars, we found that ‘Elsie Lee’ is the most cold hardy one. Through the analysis of the transcriptome data before and after cold acclimation, find R2R3 MYB genes were highly upregulated. Here, we intend to determine their type, sequence characteristics, subcellular localization and transcriptional activation activity by the full-length cloning and comparative analysis of the MYB genes in rhododendron. The expression patterns of MYB genes will be analyzed under cold acclimation and normal growth conditions in different cold-resistant cultivars. Phenotypic analysis and functional identification will be performed on transgenic Arabidopsis thaliana. The downstream target genes will be screened by ChIP-seq on transgenic rhododendron, and whether their promoter sequences can be bound to MYBs will be verified both in vivo and in vitro. The expression of downstream target genes in cold-acclimation of rhododendron will be determined. So far, we could explore the molecular regulation mechanism of MYBs involvement in the cold-acclimation of rhododendron to improve its freezing tolerance. This study can not only enrich the theory of MYB transcription factors regulation of cold stress response, can also provide molecular reference for breeding cold-resistant rhododendron germplasm.