AabZlP1 positively regulates the biosynthesis of monoterpenes and sesquiterpenes in Artemisia annua

Artemisia annua synthesizes not only artemisinin but also diverse monoterpenes and non-artemisinin sesquiterpenes, which are widely utilized as aromatic and flavoring agents in the food, cosmetic, and healthcare industries. However, the regulatory mechanisms governing their biosynthesis remain unclear. In this study, we report that AabZIP1, an abscisic acid (ABA)-responsive bZIP transcription factor, modulates both monoterpene and sesquiterpene biosynthesis in A. annua. ABA exposure upregulated the expression of numerous terpene synthase (TPS) genes, including AaBPS, AaTPS5, AaBFS, AaCPS, AaECS, and AaGAS. Dual-luciferase assays, yeast one-hybrid, and electrophoretic mobility shift assays demonstrated that AabZIP1 directly bound to the promoters of AaBPS, AaCPS, and AaGAS, and indirectly modulates the others. Overexpression of AabZIP1 led to the significant increase of β-pinene, camphene, β-caryophyllene, cedrol, and germacrene A contents in transgenic plants. These findings establish AabZIP1 as a positive modulator of terpene synthesis and offer a molecular target for engineering A. annua to enhance the production of high-value terpenoids.