Differential transcriptome and metabolome analysis of Plumbago zeylanica L. reveal putative genes involved in plumbagin biosynthesis

Plumbagin is a pharmacologically active naphthoquinone present in the Plumbago zeylanica L. having important medicinal properties. The root of P. zeylanica is rich and primary tissue of the plumbagin biosynthesis and accumulation. The complete biosynthetic pathway of plumbagin in plant is still obscure. The present study attempts to understand the plumbagin biosynthetic pathway with the help of differential transcriptome and metabolome analysis of P. zeylanica leaf and root. The transcriptome data showed co-expression of Aldo-keto reductase (PzAKR), Polyketide cyclase (Pzcyclase) and Cytochrome P450 (PzCYPs) transcripts along with the Polyketide synthase (PzPKS) transcripts. Their higher expression in root as compared to leaf supports their possible involvement in plumbagin biosynthesis. The metabolome data of leaf and root revealed naphthalene derivative isoshinanolone that could be potential precursor of plumbagin. Pathway elucidation and transcriptome data of P. zeylanica, will enable and accelerate research on naphthoquinone biosynthesis in plants. [Display omitted] •The medicinally important plant, Plumbago zeylanica L. roots accumulate antitumor compound plumbagin.•The polyketide synthase is the only known enzyme from plumbagin biosynthetic.•We propose aldo-keto reductase, polyketide cyclase and cytochrome P450s as candidate pathway genes.•Differential metabolites analysis suggests that isoshinanolone could be potential precursor of plumbagin biosynthesis.•Study enhances genomic resource of Plumbago zeylanica and will help in accelerating the research on polyketide biosynthesis.