Identification of triterpene and sesquiterpene biosynthetic pathway genes in Citrullus colocynthis L. fruit using Next Generation Sequencing (NGS) technology

Identification of the genes biosynthesizing medicinal plants-specific metabolites is now performed with great speed and accuracy using new transcriptome study technologies such as RNA sequencing. The present study was carried out to find the specific genes in the biosynthetic pathway of triterpenes and sesquiterpenes in the fruit tissue of colocynth (Citrullus colocynthis L.). After RNA extraction from the tissue of colocynth fruits harvested from Andimeshk region in Khuzestan province in 2017, RNA sequencing technique was performed using the Illumina HiSeq2500 platform. The bioinformatics steps including de novo assembly, using the Evidential-gene software, and functional annotation, using the KAAS database, were performed. In the KAAS database, 17359 unigenes were annotated in 134 plant pathways. Among the different and important secondary metabolites pathways in the fruit tissue of colocynth, 39 unigenes and 8 orthologous genes were assigned to the triterpenes and sesquiterpenes gene pathways. Transcriptome analysis of this medicinal plant with the aim of identifying the genes of secondary metabolites biosynthetic pathways underlies various research and practical aspects such as biosynthetic pathway engineering of herbal medicines.