CmRAP2.2与CmMYB1R1L蛋白复合体调控菊花耐涝性分子机制研究

菊花原产我国，具有极高的观赏和经济价值。涝渍是制约菊花产业发展的主要胁迫之一，而菊花耐涝性分子机制研究还很滞后，限制了菊花耐涝性改良进程。项目组前期基于高密度遗传图谱的连锁作图结合转录组分析，在主效QTL qWAT6.1候选区间内挖掘出明显受涝渍胁迫诱导的VII ERF基因CmRAP2.2，发现其与CmMYB1R1L互作，且异源超表达CmRAP2.2和CmMYB1R1L均能增强拟南芥耐涝性，但其互作调控耐涝性分子机制未知。为此，本项目拟创制CmRAP2.2、CmMYB1R1L转基因菊花，明确其调控菊花耐涝性功能；基于瞬时基因沉默技术，阐明CmRAP2.2与CmMYB1R1L蛋白复合体调控菊花耐涝性的作用机制；通过转录组测序等，揭示CmRAP2.2和CmMYB1R1L共同调控的下游耐涝相关分子通路。研究结果将为菊花耐涝育种提供理论依据和基因资源，并有望丰富植物耐涝分子调控网络。

Chrysanthemum originates from China with high ornamental and economic values. Waterlogging is a major abiotic stress that adversely affects chrysanthemum’s production. However, little information is known about molecular mechanism for waterlogging tolerance in chrysanthemum, which hinders the process of chrysanthemum genetic improvement. Combining linkage mapping based on a high-density genetic map and transcriptome analysis，we excavated a VII ERF gene CmRAP2.2 in the candidate interval of the main-effect QTL termed qWAT6.1, which was obviously induced by waterlogging stress. Further study indicated CmRAP2.2 interacted with CmMYB1R1L, and heterologous over-expression of CmRAP2.2 and CmMYB1R1L both enhanced waterlogging tolerance in Arabidopsis, whereas the molecular mechanism of their interaction regulating waterlogging tolerance is unknown. Therefore, this project is dedicated to create CmRAP2.2 and CmMYB1R1L transgenic chrysanthemums to identify their functions in regulating the waterlogging tolerance of chrysanthemum; clarify the mechanism of CmRAP2.2 and CmMYB1R1L complex involved in chrysanthemum waterlogging tolerance based on transient gene silencing technology; uncover downstream waterlogging tolerance-related molecular pathways co-regulated by CmRAP2.2 and CmMYB1R1L via transcriptome sequencing. The findings of this study will provide theoretical basis and genetic resources for chrysanthemum waterlogging tolerance breeding, and hopefully enrich the plant's waterlogging tolerance molecular regulation network.