AUTHOR=Dong Boran , Wang Xingxing , Jiang Rui , Fang Shiyuan , Li Jinxing , Li Qing , Lv Zong you , Chen Wan sheng 

TITLE=AaCycTL Regulates Cuticle and Trichome Development in Arabidopsis and Artemisia annua L.

JOURNAL=Frontiers in Plant Science

VOLUME=12

YEAR=2021

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2021.808283

DOI=10.3389/fpls.2021.808283

ISSN=1664-462X

ABSTRACT=<p>Artemisinin is an important drug for resistance against malaria. Artemisinin is derived from the glandular trichome of leaves, stems, or buds of the Chinese traditional herb <italic>Artemisia annua</italic>. Increasing the trichome density may enhance the artemisinin content of <italic>A. annua</italic>. It has been proven that cyclins are involved in the development of trichomes in tomato, Arabidopsis, and tobacco, but it is unclear whether the cyclins in <italic>A. annua</italic> influence trichome development. In this study, we showed that <italic>AaCycTL</italic> may regulate trichome development and affect the content of artemisinin. We cloned <italic>AaCycTL</italic> and found that it has the same expression files as the artemisinin biosynthesis pathway gene. We overexpressed <italic>AaCycTL</italic> in Arabidopsis, and the results indicated that <italic>AaCycTL</italic> changed the wax coverage on the surface of Arabidopsis leaves. The trichome density decreased as well. Using yeast two-hybrid and BiFC assays, we show that <italic>AaCycTL</italic> can interact with <italic>AaTAR1</italic>. Moreover, we overexpressed <italic>AaCycTL</italic> in <italic>A. annua</italic> and found that the expression of <italic>AaCycTL</italic> was increased to 82–195%. Changes in wax coverage on the surface of transgenic <italic>A. annua</italic> leaves or stems were found as well. We identified the expression of the artemisinin biosynthesis pathway genes <italic>ADS</italic>, <italic>CYP71AV1</italic>, and <italic>ALDH1</italic> has decreased to 88–98%, 76–97%, and 82–97% in the <italic>AaCycTL</italic>-overexpressing <italic>A. annua</italic> lines, respectively. Furthermore, we found reduced the content of artemisinin. In agreement, overexpression of <italic>AaCycTL</italic> in <italic>A. annua</italic> or Arabidopsis may alter waxy loading, change the initiation of trichomes and downregulate trichome density. Altogether, <italic>AaCycTL</italic> mediates trichome development in <italic>A. annua</italic> and thus may serve to regulate trichome density and be used for artemisinin biosynthesis.</p>