Phenolic acids and tanshinones are main bioactive compounds produced in Salvia miltiorrhiza widely used in treatment of cardiovascular diseases, which could be promoted by abscisic acid elicitation. However, the regulation mechanism remained to be elucidated. An ABA-inducible IIa WRKY transcription factor (TF) named SmWRKY34 exhibiting high homology with AtWRKY40 was isolated. SmWRKY34 exhibited a negative role on phenolic acids and tanshinones by directly regulating SmRAS and SmGGPPS. Moreover, ABA-responsive bZIP TF member named SmbZIP3 expressing significantly in SmWRKY34 transcriptome was screened. SmWRKY34 showed a negative regulatory role on SmbZIP3. SmbZIP3 acted as a positive regulator in the biosynthesis of phenolic acids and tanshinones by targeting SmTAT and two tanshinone-promoting TFs SmERF128 and SmMYB9b. Taken together, we identify a new module WRKY34-bZIP3 involved in ABA signaling that manipulates phenolic acid and tanshinone accumulation, shedding new insights in metabolic engineering application in S. miltiorrhiza.

丹参中产生的酚酸和丹参酮是主要的生物活性化合物，广泛用于心血管疾病的治疗，可通过脱落酸诱导促进。然而，调控机制仍有待阐明。分离出与 AtWRKY40 具有高度同源性的名为SmWRKY34的 ABA 诱导型 IIa WRKY 转录因子 (TF) 。SmWRKY34通过直接调节SmRAS和SmGGPPS对酚酸和丹参酮表现出负面作用。此外，筛选了在SmWRKY34转录组中显着表达的名为SmbZIP3的 ABA 响应 bZIP TF 成员。SmWRKY34 显示对SmbZIP3的负调节作用。SmbZIP3通过靶向SmTAT和两种促进丹参酮的 TFs SmERF128和SmMYB9b在酚酸和丹参酮的生物合成中充当正调节剂。总之，我们确定了一个新的模块 WRKY34-bZIP3 参与 ABA 信号传导，它控制酚酸和丹参酮的积累，为丹参代谢工程应用提供了新的见解。