Metabolic Regulation and Engineering of Artemisinin Biosynthesis in A. Annua

Artemisinin is a potent anti-malarial sesquiterpene lactone that is naturally biosynthesized in glandular trichomes of a Chinese herbal plant, Artemisia annua. Although semi-synthesis of artemisinin in yeast has been feasible, at present the A. annua plant is still the main commercial source of artemisinin. The content of artemisinin however is low in A. annua, limiting its supply to malarial victims. So it's crucial to elevate artemisinin production in A. annua. Up to date artemisinin biosynthetic pathway has been completely elucidated. And many regulatory factors, mediating diverse plant hormone or environmental signaling routes, have been identified to get involved in the regulation of artemisinin biosynthesis and glandular trichome formation. Understanding the regulatory mechanisms of artemisinin biosynthesis and glandular trichome formation will be conducive to our practice for improving artemisinin production by metabolic engineering. In this review, the metabolic regulatory network with regard to artemisinin biosynthesis and glandular trichome formation is summarized, and the advance on metabolic engineering to increase artemisinin content in A. annua is also discussed.