Transcriptome-wide mining suggests conglomerate of genes associated with tuberous root growth and development in Aconitum heterophyllum Wall

Abstract

Tuberous roots of Aconitum heterophyllum constitute storage organ for secondary metabolites, however, molecular components contributing to their formation are not known. The transcriptomes of A. heterophyllum were analyzed to identify possible genes associated with tuberous root development by taking clues from genes implicated in other plant species. Out of 18 genes, eight genes encoding GDP-mannose pyrophosphorylase (GMPase), SHAGGY, Expansin, RING-box protein 1 (RBX1), SRF receptor kinase (SRF), b-amylase, ADPglucose pyrophosphorylase (AGPase) and Auxin responsive factor 2 (ARF2) showed higher transcript abundance in roots (13–171 folds) compared to shoots. Comparative expression analysis of those genes between tuberous root developmental stages showed 11–97 folds increase in transcripts in fully developed roots compared to young rootlets, thereby implying their association in biosynthesis, accumulation and storage of primary metabolites towards root biomass. Cluster analysis revealed a positive correlation with the gene expression data for different stages of tuberous root formation in A. heterophyllum. The outcome of this study can be useful in genetic improvement of A. heterophyllum for root biomass yield.