Frontiers Science Center for Transformative Molecules, Joint International Research Laboratory of Metabolic & Developmental Sciences, Key Laboratory of Urban Agriculture (South) Ministry of Agriculture, Plant Biotechnology Research Center, Fudan-SJTU-Nottingham Plant Biotechnology R&D Center, School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai 200240, China.
Frontiers Science Center for Transformative Molecules, Joint International Research Laboratory of Metabolic & Developmental Sciences, Key Laboratory of Urban Agriculture (South) Ministry of Agriculture, Plant Biotechnology Research Center, Fudan-SJTU-Nottingham Plant Biotechnology R&D Center, School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai 200240, China.
J Plant Physiol. 2022 Jul;274:153712. doi: 10.1016/j.jplph.2022.153712. Epub 2022 May 23.
Malaria is a devastating parasitic disease with high levels of morbidity and mortality worldwide. Artemisinin, the active substance against malaria, is a sesquiterpenoid produced by Artemisia annua. To improve artemisinin content in the native A. annua plants, considerable efforts have been attempted, with genetic transformation serving as an effective strategy. Although, the most frequently-used cauliflower mosaic virus (CaMV) 35S (CaMV35S) promoter has proved to be efficient in A. annua transgenic studies, it appears to show weak activity in peltate glandular secretory trichomes (GSTs) of A. annua plants. Here, we characterized the 1727 bp fragment upstream from the translation start codon (ATG) of AaActin1, however, found it was inactive in tobacco. After removal of the 5' intron, the truncated AaActin1 promoter (tpACT) showed 69% and 50% activity of CaMV35S promoter in transiently transformed tobacco and stably transformed A. annua, respectively. β-glucuronidase (GUS) staining analysis showed that the tpACT promoter was capable of directing the constant expression of a foreign gene in peltate GSTs of transgenic A. annua, representing higher activity than CaMV35S promoter. Collectively, our study provided a novel promoter available for metabolic engineering of artemisinin biosynthesis in A. annua.
疟疾是一种具有高发病率和死亡率的毁灭性寄生虫病。青蒿素是一种抗疟的活性物质，它是由黄花蒿产生的倍半萜。为了提高本地黄花蒿植物中的青蒿素含量，人们已经尝试了相当多的努力，其中遗传转化是一种有效的策略。虽然最常用的花椰菜花叶病毒（CaMV）35S（CaMV35S）启动子已被证明在黄花蒿的转基因研究中是有效的，但它在黄花蒿植物的盾状腺毛分泌细胞（GSTs）中似乎表现出较弱的活性。在这里，我们对翻译起始密码子（ATG）上游的 1727bp 片段进行了特征分析，但发现它在烟草中没有活性。去除 5'内含子后，截短的 AaActin1 启动子（tpACT）在瞬时转化的烟草和稳定转化的黄花蒿中的活性分别为 CaMV35S 启动子的 69%和 50%。β-葡萄糖醛酸酶（GUS）染色分析表明，tpACT 启动子能够在转基因黄花蒿的盾状 GSTs 中指导外源基因的持续表达，其活性高于 CaMV35S 启动子。总之，我们的研究为黄花蒿青蒿素生物合成的代谢工程提供了一种新的启动子。
