Promotion of artemisinin biosynthesis in transgenic Artemisia annua by overexpressing ADS, CYP71AV1 and CPR genes

Abstract

Artemisinin is an effective anti-malarial drug isolated from A. annua, which has an enormous commercialization demand all over the world. However, the low artemisinin content of A. annua greatly limits the commercialization of artemisinin. In this study, we report the results of our experiments, where for the first time we have achieved the overexpression of ADS, CYP71AV1 and CPR genes in A. annua. Eight transgenic A. annua plants were obtained through Agrobacterium tumefaciens-mediated transformation, which was confirmed by PCR. Southern-blot analyses showed that some of the transgenic lines had low copies of the integration transgenes. The results of real time-qPCR showed that the expression levels of ADS, CYP71AV1 and CPR genes were significantly increased, too. The HPLC analyses showed that the artemisinin contents were significantly increased in these transgenic plants. One of the transgenic plants, ACR16, was found to contain 2.4-fold higher (15.1mg/g DW) artemisinin than the control plants (pCAMBIA2300 transgenic plants). All above results showed that overexpression of ADS, CYP71AV1 and CPR genes in A. annua could promoted the metabolic flux flows toward biosynthesis of artemisinin and effectively increase the level of artemisinin content in transgenic A. annua plants.