Characterization and function of short-chain dehydrogenases/reductases in hydroxysafflower yellow A biosynthesis pathway / 药学实践杂志

ABSTRACT

Objective To explore the function of short-chain dehydrogenases/reductases (SDRs) in safflower flavonoid, especially hydroxysafflower yellow A (HSYA) biosynthesis. Methods SDRs involved in HSYA biosynthesis pathway were screened based on safflower transcriptome database and metabolome database. The expression pattern was analyzed by qRT-PCR. The overexpression vector was constructed by seamless cloning technology, then genetically transformed to the Yunnan Weishan safflower strain by Agrobacterium gv3101. The transgenic T2 generation plants were positively verified, and the gene expression of corolla SDRs was analyzed. The content of secondary metabolites was assayed by UPLC-Q-TOF/MS. Results Three SDRs genes named CtSDR1, CtSDR2 and CtSDR3 involved in HSYA biosynthesis pathway were screened. Their expression in safflower from high to low was corolla > leaf > stem > root. The expression level in corolla increased gradually with corolla development. qRT-PCR analysis of corolla with positive verification of genome insertion sequence showed that the transcription level of CtSDR3 in corolla of T2 positive plants increased by 2~3 times compared with the blank control group, and the content of secondary metabolite HSYA increased by 7.1%~16.6% (P< 0.05). Conclusion CtSDR3 may be involved in the biosynthesis of flavonoids, especially HSYA, in safflower. It provides the support data for explaining the function of CtSDR3 in HSYA biosynthesis pathway.