黄酮化合物是植物重要的次生代谢物，与植物适应环境和抗逆有重要的关系。我们前期研究光质对烟草黄酮化合物积累的影响，发现高比例的UV-A能够抑制黄酮甲基衍生物的积累，而远红光促进其积累，与黄酮及黄酮糖苷衍生物受光质调控的模式相反，并且黄酮甲基转移酶基因（NtFOMT）与主要黄酮合成基因受光质调控的表达模式相矛盾。为了研究光质调控黄酮甲基化反应的机理，本研究利用基因组步移技术，从烟草基因组中克隆到NtFOMT基因的启动子。并进行启动子5’端连续缺失片段切割，构建融合YFP的表达载体，明确了响应光质调控的启动子片段。后续拟通过定点突变分析确定响应光质调控的顺式作用元件，然后利用酵母单杂交方法克隆介导光质调控的转录因子。通过综合分析不同光质条件下转录因子和NtFOMT的表达规律以及黄酮甲基衍生物的积累规律，明确光质调控黄酮甲基化反应的机理，为光质调控植物次生代谢提供理论基础。

Flavonoids are important secondary metabolites in plants and play an important role in the biological processes related to the adaptation of plants to the environment and stress resistance. In our previous study, the influence of light quality on the accumulation of flavonoids in tobacco was studied and the result indicated that the accumulation of flavonoid methyl derivatives was negatively correlated with the proportion of ultraviolet (UV-A; 350–400 nm) and positively correlated with the proportions of far-red light (FR; 716–810 nm), which was contrary to the mode of flavonoid and its glycoside derivatives regulated by light quality. The expression pattern of NtFOMT regulated by light quality was conflict with the main synthetic gene of flavonoid. To study the mechanism of flavonoid methylation reaction regulated by light quality, the promoter of NtFOMT was cloned from tobacco with the method of genome walking and five 5' truncated fragments of the promoter were used to construct a carrier containing YFP reporter gene. In this study, the site-directed mutagenesis technique will be employed to analyze cis-acting element response to the regulation of light quality and the transcription factor will be cloned by the yeast one hybrid system. The mechanism of flavonoid methylation regulated by light quality will be discussed by analyzing the transcription factor, expression profile of NtFOMT and accumulation of flavonoid methyl derivatives. The results will establish a theoretical basis for the study of plant secondary metabolism regulated by light quality.