月季是全球第一大切花。在我国，月季冬季生产效益最高。然而，低温条件（<10℃）往往引起花瓣过度重瓣化，导致花朵畸形，严重影响切花品质。申请者通过原位杂交和基因沉默等手段，明确了RhAG基因在花朵过度重瓣化中起到了重要作用，并通过对RhAG沉默植株与正常植株的转录组数据比较，发现了多个差异表达的转录因子基因。本项目拟对确受RhAG调控的下游基因展开筛选。同时，利用已克隆的RhAG启动子，开展响应低温，调节RhAG表达的上游转录因子筛选。通过基因沉默方法明确RhAG上游和下游候选基因的功能；基于原位杂交技术分析其时空表达特性；通过EMSA、ChIP和转录激活等技术证实候选基因与RhAG的上下游关系。项目力图从转录层面探讨以RhAG为重要节点的基因调节网络及其在低温调节花朵发育中的作用机制，进而为解决月季冬季生产中花朵畸形这一实践中的瓶颈问题提供理论依据，并为月季品质改良分子育种提供基因储备。

Rose is one of the most important cut flowers in the world. In China, production of cut rose flower would have higher profit in the winter than other seasons due to the price. However, low temperatures（<10℃）in the winter would cause formation of excessive petal, resulting in low quality flowers with abnormal shape. Our previous work demonstrated that RhAG plays an important role in petal development under low temperature by In situ hybridazition and VIGS approach and we found some the transcription factor genes with expression differences by comparing the transcriptomic profiles of normal flowers and RhAG-silenced ones. Here, we propose to isolate downstream gene regulated by RhAG. In addition, we try to isolate the potential transcription factors which regulate RhAG by yeast-one-hybrid using the promoter of RhAG. Then we will confirm the function of candidate genes in petal development using VIGS approach. In situ hybridazition will be conducted to show the temporal and spatial expression pattern of candidates, while EMSA, ChIP and transactivation assay will be used to make sure the regulatory relationship of RhAG and the candidates. Base on these works, we try to establish the RhAG-dependent transcriptional regulatory network and the central role of RhAG. The results should shed lights on the molecular mechanism of low-temperature induced excessive and aberrant petal formation in rose, and may provide potential genes for molecular breeding in the future.