Identification and Gene Expression Analyses of Cytochrome P450 Candidates for Glycyrrhizin and Abrusoside Biosynthesis in Abrus precatorius

Abstract

Triterpenoid saponins are glycoside triterpenes in the saponin group that have significant medicinal properties that include anti-inflammatory, antibacterial, antifungal, and antioxidant activities. Abrusoside and glycyrrhizin, part of the triterpenoid saponins, are bioactive compounds that are produced in Abrus precatorius. Although it has the potential to play critical roles in multiple industries, the specific enzymes and biosynthesis pathway are still understudied. This study aims to identify and characterize CYP450 candidates differentially expressed in A. precatorius under combined hydroponic and MeJA stress for abrusoside/glycyrrhizin biosynthesis. Transcriptomics data was filtered to select CYP450 candidates followed by transcript expression level visualization using heatmap. Candidate gene characterization analysis was conducted by generation of phylogeny trees built using MEGA11, identification of conserved motifs using MEME-suite, and predicted protein 3D structures modelling using AlphaFold. Selected candidates based on the expression data and gene characterization were used for primer design for qualitative polymerase chain reaction (qPCR) analysis to further validate the transcriptomic data. Primer pairs were designed using Primer-BLAST/Primer3, first strand cDNA was synthesised, and PCR condition was optimized. A total of 88