TRICHOME AND ARTEMISININ REGULATOR 1 Is Required for Trichome Development and Artemisinin Biosynthesis in Artemisia annua.

Abstract

Trichomes, small protrusions on the surface of many plant species, can produce and store various secondary metabolic products. Artemisinin, the most famous and potent medicine for malaria, is synthesized, stored, and secreted by Artemisia annua trichomes. However, the molecular basis regulating the biosynthesis of artemisinin and the development of trichomes in A. annua remains poorly understood. Here, we report that an AP2 transcription factor, TRICHOME AND ARTEMISININ REGULATOR 1 (TAR1), plays crucial roles in regulating the development of trichomes and the biosynthesis of artemisinin in A. annua. TAR1, which encodes a protein specially located in the nucleus, is mainly expressed in young leaves, flower buds, and some trichomes. In TAR1-RNAi lines, the morphology of trichomes and the composition of cuticular wax were altered, and the artemisinin content was dramatically reduced, which could be significantly increased by TAR1 oeverexpression. Expression levels of several key genes that are involved in artemisinin biosynthesis were altered when TAR1 was silenced or overexpressed. By the electrophoretic mobility shift, yeast one-hybrid and transient transformation β-glucuronidase assays, we showed that ADS and CYP71AV1, two key genes in the biosynthesis pathway of artemisinin, are likely the direct targets of TAR1. Taken together, our results indicate that TAR1 is a key component of the molecular network regulating trichome development and artemisinin biosynthesis in A. annua.

• Authors: Hexin Tan, Ling Xiao, Shouhong Gao, Qing Li, Junfeng Chen, Ying Xiao, Qian Ji, Ruibing Chen, Wansheng Chen, Lei Zhang
• Journal: Molecular plant (Mol Plant) Vol. 8 Issue 9 Pg. 1396-411 (Sep 2015) ISSN: 1752-9867 [Electronic] England
• PMID: 25870149 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: Copyright © 2015 The Author. Published by Elsevier Inc. All rights reserved.

Chemical References

• Artemisinins
• Plant Proteins
• Waxes
• artemisinin

Topics

• Amino Acid Sequence
• Artemisia annua (genetics, metabolism)
• Artemisinins (chemistry, metabolism)
• Base Sequence
• Biosynthetic Pathways
• Cell Nucleus (metabolism)
• Flowers (metabolism)
• Gene Expression Regulation, Plant
• Gene Silencing
• Genes, Plant
• Molecular Sequence Data
• Phenotype
• Plant Epidermis (metabolism)
• Plant Leaves (metabolism, ultrastructure)
• Plant Proteins (chemistry, metabolism)
• Protein Binding
• Protein Transport
• RNA Interference
• Sequence Analysis, DNA
• Trichomes (growth & development, metabolism)
• Waxes (metabolism)