AUTHOR=Zhou Wei , Wang Shuai , Shen Yafang , Liu Yunhui , Maoz Itay , Gao Xiankui , Chen Chengan , Liu Tingyao , Wang Can , Kai Guoyin 

TITLE=Overexpression of SmSCR1 Promotes Tanshinone Accumulation and Hairy Root Growth in Salvia miltiorrhiza

JOURNAL=Frontiers in Plant Science

VOLUME=13

YEAR=2022

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2022.860033

DOI=10.3389/fpls.2022.860033

ISSN=1664-462X

ABSTRACT=<p>Lipid-soluble tanshinone is one of the main bioactive substances in the medicinal plant <italic>Salvia miltiorrhiza</italic>, and its medicinal demand is growing rapidly. Yeast extract (YE) modulates the tanshinone biosynthesis, but the underlying regulatory network remains obscure. In this study, a YE-responsive transcriptional factor Scarecrow1 (<italic>SCR1</italic>) was identified in <italic>S. miltiorrhiza</italic> from the YE-induced transcriptome dataset. <italic>SmSCR1</italic> is located in the nucleus. Overexpression of <italic>SmSCR1</italic> in <italic>S. miltiorrhiza</italic> roots resulted in a significantly higher accumulation of tanshinone than the control, with the highest 1.49-fold increase. We also detected upregulation of tanshinone biosynthetic genes, <italic>SmSCR1</italic> and <italic>SmHMGR1</italic>, and distinct alteration of growth and development of the hairy roots in the overexpression lines compared to the control. An inverse phenotype was observed in <italic>SmSCR1</italic>-SRDX suppression expression lines. We found that <italic>SmSCR1</italic> can bind to the promoter of <italic>SmCPS1</italic> to induce its expression. This study provides new insight into the regulatory mechanism on the growth and development of hairy roots, tanshinone accumulation, and the metabolic engineering of bioactive compounds in <italic>S. miltiorrhiza</italic>.</p>