Histone Deacetylase GiSRT2 Negatively Regulates Flavonoid Biosynthesis in <i>Glycyrrhiza inflata</i>
Jiangyi Zeng,
Yun Huang,
Lijun Zhou,
Xiaoju Liang,
Chao Yang,
Hongxia Wang,
Ling Yuan,
Ying Wang,
Yongqing Li
Affiliations
Jiangyi Zeng
Guangdong Provincial Key Laboratory of Applied Botany & Guangdong Provincial Key Laboratory of Digital Botanical Garden, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China
Yun Huang
Guangdong Provincial Key Laboratory of Applied Botany & Guangdong Provincial Key Laboratory of Digital Botanical Garden, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China
Lijun Zhou
Guangdong Provincial Key Laboratory of Applied Botany & Guangdong Provincial Key Laboratory of Digital Botanical Garden, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China
Xiaoju Liang
Guangdong Provincial Key Laboratory of Applied Botany & Guangdong Provincial Key Laboratory of Digital Botanical Garden, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China
Chao Yang
Guangdong Provincial Key Laboratory of Applied Botany & Guangdong Provincial Key Laboratory of Digital Botanical Garden, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China
Hongxia Wang
University of Chinese Academy of Sciences, Beijing 100049, China
Ling Yuan
Department of Plant and Soil Sciences, University of Kentucky, Lexington, KY 40506, USA
Ying Wang
Guangdong Provincial Key Laboratory of Applied Botany & Guangdong Provincial Key Laboratory of Digital Botanical Garden, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China
Yongqing Li
Guangdong Provincial Key Laboratory of Applied Botany & Guangdong Provincial Key Laboratory of Digital Botanical Garden, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China
Glycyrrhiza inflata Batalin is a medicinal licorice species that has been widely used by humans for centuries. Licochalcone A (LCA) is a characteristic flavonoid that accumulates in G. inflata roots with high economical value. However, the biosynthetic pathway and regulatory network of its accumulation remain largely unknown. Here we found that a histone deacetylase (HDAC) inhibitor nicotinamide (NIC) could enhance the accumulation of LCA and total flavonoids in G. inflata seedlings. GiSRT2, a NIC-targeted HDAC was functionally analyzed and its RNAi transgenic hairy roots accumulated much more LCA and total flavonoids than its OE lines and the controls, indicating a negative regulatory role of GiSRT2 in the accumulation of LCA and total flavonoids. Co-analysis of transcriptome and metabolome of RNAi-GiSRT2 lines revealed potential mechanisms in this process. An O-methyltransferase gene, GiLMT1 was up-regulated in RNAi-GiSRT2 lines and the encoded enzyme catalyzed an intermediate step in LCA biosynthesis pathway. Transgenic hairy roots of GiLMT1 proved that GiLMT1 is required for LCA accumulation. Together, this work highlights the critical role of GiSRT2 in the regulation of flavonoid biosynthesis and identifies GiLMT1 as a candidate gene for the biosynthesis of LCA with synthetic biology approaches.
