Wang Ting, Li Mengke, Tang Xu, He Yao, Fang Qing, Fan Tingting, Liu Shishi, Deng Kejun
Department of Biotechnology, School of Life Sciences and Technology, Center for Informational Biology, Innovation Center for Electronic Information & Traditional Chinese Medicine, University of Electronic Science and Technology of China, Chengdu 610054, China.
Chongqing Key Laboratory of Plant Resource Conservation and Germplasm Innovation, Integrative Science Center of Germplasm Creation in Western China (Chongqing) Science City, School of Life Sciences, Southwest University, 400715 Chongqing, China.
Int J Biol Macromol. 2025 Jul;318(Pt 3):145067. doi: 10.1016/j.ijbiomac.2025.145067. Epub 2025 Jun 6.
Transcription factors (TFs) are crucial in regulating secondary metabolic pathways, it is still a hot topic in drug mechanism research. However, the exploration and validation of its functions are far from sufficient. We presented the functional analysis of SmbHLH125, a novel bHLH transcription factor from Salvia miltiorrhiza. Overexpression of SmbHLH125 inhibited hairy root elongation, whereas knockout could grow normally, reduced rosmarinic acid levels, and increased salvianolic acid B and tanshinones. Muti-omics and yeast one-hybrid assays revealed that SmbHLH125 binds to the promoters of Sm4CL3 and SmHMGR1, key enzyme genes of biosynthesis pathway of phenolic acids and tanshinones respectively, and negatively regulates their expressions. It also binds to the promoters of SmAACT2, SmDXR and SmMK to positively regulates their expression. Moreover, we found that SmbHLH125 regulates a variety of functional phenolic acids and tanshinones. Therefore, we explored deeper that SmLAC7, CYP736A12 and CYP71AU50 might be potential enzymes genes for phenolic acid synthesis, and CYP736A12, CYP92B28, CYP71AU50, CYP97C28 and CYP71A6 may be catalase genes for tanshinone synthesis through gene-metabolite co-expression analysis. In conclusion, we have identified a new regulator with broad effects on secondary metabolism and provides a new perspective for analyzing and predicting gene functions.
转录因子（TFs）在调节次生代谢途径中起着关键作用，这仍是药物机制研究中的一个热门话题。然而，对其功能的探索和验证还远远不够。我们对丹参中一种新的bHLH转录因子SmbHLH125进行了功能分析。SmbHLH125的过表达抑制了毛状根的伸长，而敲除则能正常生长，降低了迷迭香酸水平，并增加了丹酚酸B和丹参酮的含量。多组学和酵母单杂交试验表明，SmbHLH125分别与酚酸和丹参酮生物合成途径的关键酶基因Sm4CL3和SmHMGR1的启动子结合，并对其表达起负调控作用。它还与SmAACT2、SmDXR和SmMK的启动子结合，对其表达起正调控作用。此外，我们发现SmbHLH125调节多种功能性酚酸和丹参酮。因此，我们通过基因-代谢物共表达分析进一步探索发现，SmLAC7、CYP736A12和CYP71AU50可能是酚酸合成的潜在酶基因，而CYP736A12、CYP92B28、CYP71AU50、CYP97C28和CYP71A6可能是丹参酮合成的过氧化氢酶基因。总之，我们鉴定出了一种对次生代谢具有广泛影响的新调节因子，为分析和预测基因功能提供了新的视角。
