目的 探究淹水胁迫对杭菊绿原酸合成途径中的关键酶香豆酰基喹酸酯3'-单加氧酶（C3'H）和莽草酸羟基肉桂酰基转移酶（HCT）基因的表达和活性成分的影响。方法 使用实时荧光定量PCR（qRT-PCR）方法基于杭菊转录组数据库克隆HCT和C3'H基因各2个，其中C3'H酶的2个基因CmC3'H1、CmC3'H2，HCT酶的2个基因CmHCT1、CmHCT2，并进行生物信息学分析；同时在杭菊花芽分化期进行淹水胁迫，以β-actin为内参基因，使用qRT-PCR检测以上4个基因的相对表达量；然后使用HPLC法测定杭菊这4个基因的下游产物及其他指标成分含量。结果 通过研究获得了4条基因的完整开放阅读框，并且预测其氨基酸序列的相对分子质量和理论等电点（pI），同时构建蛋白质三级结构模型。qRT-PCR结果显示在花芽分化期对杭菊进行持续3 d的淹水处理会导致以上4个基因在不同生长时期内的表达显著变化。HPLC结果显示淹水处理后的杭菊C3'H和HCT所催化形成的下游产物绿原酸含量显著高于对照组，同时发现其他2种指标成分木犀草苷和3，5-O-二咖啡酰基奎宁酸含量也显著高于对照组。结论 杭菊在淹水胁迫下可以通过调节4种基因的表达来调控下游产物的合成，从而对淹水胁迫做出应答，而且花芽分化期进行淹水胁迫可以显著增强杭菊活性成分的积累。

To investigate the effects of the expression of coumaroylquinate 3'-monooxygenase (C3'H) and shikimate O-hydroxycinnamoyltransferase (HCT) in the chlorogenic acid-producing pathway and active ingredients in Chrysanthemum morifolium under flooding stress, we cloned two C3'H genes which were CmC3'H1 and CmC3'H2 and two HCT genes which were CmHCT1 and CmHCT2 by the RT-PCR from Hangju and conducted bioinformatics analysis. During the flower bud differentiation stage, we flooded the C. morifolium and then used β-actin as the reference gene to detect the relative expression of the four genes by the qRT-PCR. Finally, the content of downstream products and other indicators of these four genes in C. morifolium were measured by HPLC. We obtained the four genes' complete open reading frame and predicted the relative molecular mass of the amino acid sequence and the theoretical isoelectric point (pI). And the protein tertiary structure models were constructed. The qRT-PCR results showed that flooding the C. morifolium for 3 days during the flower bud differentiation stage resulted in significant expression changes of the four genes at different growth stages. The results of HPLC showed that chlorogenic acid, the downstream product catalyzed by the C3'H and the HCT, was significantly higher than that in the control group. It was also found that the content of luteoloside and 3,5-O-di-caffeoylquinic acid was also significantly higher than those of the control group. Therefore, C. morifolium regulates the synthesis of downstream products by regulating the expression of the four genes under flooding stress, thereby responding to flooding stress. And the flooding stress during flower bud differentiation can significantly enhance the accumulation of active ingredients of C. morifolium.

R282.12

国家自然科学基金青年科学基金项目（81503180）；中央高校基本科研业务费专项资金资助项目（KJQN201643，KYZ201608）