Overexpression of blue light receptor AaCRY1 improves artemisinin content in Artemisia annua L.

Artemisinin, an effective antimalarial compound, is isolated from the medicinal plantArtemisia annuaL. However, because of the low content of artemisinin inA. annua, the demand of artemisinin exceeds supply. Previous studies show that the artemisinin biosynthesis is promoted by light inA. annua. Cryptochrome1 (CRY1) is involved in many processes in the light response. In this study,AaCRY1was cloned fromA. annua. OverexpressingAaCRY1inArabidopsis thaliana cry1mutant resulted in blue-light-dependent short hypocotyl phenotype and short coleoptile under blue light. Yeast two-hybrid and subcellular colocalization showed that AaCRY1 interacted with AtCOP1 (ubiquitin E3 ligase CONSTITUTIVE PHOTOMORPHOGENIC1). Overexpression ofAaCRY1in transgenicA. annuaincreased the artemisinin content. WhenAaCRY1was overexpressed inA. annuadriven by theCYP71AV1(cytochrome P450 dependent amorpha-4,11-diene 12-hydroxylase) promoter, the artemisinin content was 1.6 times higher than that of the control. Furthermore, we expressed the C terminal of AaCRY1(CCT) involved a GUS-CCT fusion protein inA. annua. The results showed that the artemisinin content was increased to 1.7- to 2.4-fold in GUS-CCT transgenicA. annuaplants. These results demonstrate that overexpression ofGUS-CCTis an effective strategy to increase artemisinin production inA. annua.

Automated summary

Research shows that the cryptochrome1 in Artemisia annua is involved in blue light response, promoting artemisinin biosynthesis when overexpressed. Overexpression of AaCRY1 can increase artemisinin content, with the fusion protein GUS-CCT showing the most effective results.