Chromatin Accessibility Is Associated with Artemisinin Biosynthesis Regulation in Artemisia annua.

Limeng Zhou,Yingzhang Huang,Dianjing Guo,Qi Wang

doi:10.3390/molecules26041194

Limeng Zhou, Yingzhang Huang + Show 2 more

Open Access

https://doi.org/10.3390/molecules26041194

Copy DOI

Abstract

Glandular trichome (GT) is the dominant site for artemisinin production in Artemisia annua. Several critical genes involved in artemisinin biosynthesis are specifically expressed in GT. However, the molecular mechanism of differential gene expression between GT and other tissue types remains elusive. Chromatin accessibility, defined as the degree to which nuclear molecules are able to interact with chromatin DNA, reflects gene expression capacity to a certain extent. Here, we investigated and compared the landscape of chromatin accessibility in Artemisia annua leaf and GT using the Assay for Transposase-Accessible Chromatin using sequencing (ATAC-seq) technique. We identified 5413 GT high accessible and 4045 GT low accessible regions, and these GT high accessible regions may contribute to GT-specific biological functions. Several GT-specific artemisinin biosynthetic genes, such as DBR2 and CYP71AV1, showed higher accessible regions in GT compared to that in leaf, implying that they might be regulated by chromatin accessibility. In addition, transcription factor binding motifs for MYB, bZIP, C2H2, and AP2 were overrepresented in the highly accessible chromatin regions associated with artemisinin biosynthetic genes in glandular trichomes. Finally, we proposed a working model illustrating the chromatin accessibility dynamics in regulating artemisinin biosynthetic gene expression. This work provided new insights into epigenetic regulation of gene expression in GT.

Highlights

Malaria, as one of the most-deadly diseases, threatens the lives of nearly half of the world population
We sought to investigate the accessible chromatin in Glandular trichome (GT) and leaf of Artemisia annua
These genes are likely responsible for the establishment and maintenance of cellular identity and function of glandular trichome, which is the main site for secondary metabolite biosynthesis (Figure 3D)

Summary

Introduction

As one of the most-deadly diseases, threatens the lives of nearly half of the world population. Artemisinin, a sesquiterpene metabolite discovered from Chinese herb Artemisia annua, is a potent drug against malaria [1,2]. Artemisia annua has gained increasing attention as a potential source as a drug against COVID19 [4,5]. Despite its importance, artemisinin abundance in Artemisia annua is too low (about 0.1–1.0% dry weight) to meet the increasing demands [6,7]. Artemisininrelated traits were investigated and improved through population genetics [10,11] and molecular genetic breeding [12,13]. A comprehensive understanding of artemisinin’s biosynthetic regulatory mechanism is of great importance for improving the artemisinin yield through genetic engineering approach

Methods

Results

Conclusion