Cloning and functional identification of novel <italic>CYP71D375</italic> related to tanshinone biosynthesis in <italic>Salvia miltiorrhiza</italic>

Abstract

Tanshinones, extracted from Salvia miltiorrhiza , are best known for the treatment of cardiovascular and cerebrovascular diseases, whose biosynthesis is a subject of considerable interest. Studies in elucidating tanshinone biosynthesis mainly focus on the function of CYP450 oxidase. Based on the genome and transcriptome of Salvia miltiorrhiza , a medicinal model plant, a SmCYP71D375 gene related to tanshinone biosynthesis was identified, with the entire open reading frame of 1515 base pair (bp), in length encoding one polypeptide of 504 amino acids. The expression of SmCYP71D375 was the highest in the periderm, in accordance with the synthesis and accumulation of tanshinone, indicating that SmCYP71D375 might be involved in tanshinone biosynthesis. The content of 1R-hydroxymiltirone, miltirone, cryptotanshinone, and tanshinone IIA were decreased significantly by expression inhibition of SmCYP71D375 via RNAi transgenic hairy root system, confirming that SmCYP71D375 catalyzed the biosynthesis of tanshinones in vivo . This study will help to elucidate the biosynthetic pathway of tanshinones, and pave the way for the research of synthetic pathways of high-oxide secondary metabolites in the plant kingdom.