Identification of genes involved in steroid alkaloid biosynthesis in Fritillaria imperialis via de novo transcriptomics.

Crown imperial (CI) has been used in traditional medicine. Today it is known that such beneficial effects are due to its richness in steroidal alkaloids (SA). Using de novo transcriptomics, orthologues/paralogues finder, phylogenetic analysis and tissue- and developmental stage-specific expression analysis, we identified ten genes and several TFs involved in the biosynthesis of SA in CI. The comparative analysis of ten genes expression profiles revealed the possibility of their co-regulation, which may imply the possibility of their organization in metabolic gene clusters. Having in mind convergent evolution of steroidal biosynthetic pathways in flowering plants and records of convergent evolution of specific proteins, observed expression patterns open a reasonable interest to investigate the possibility of the existence of genes cluster organization in SA pathway in the family Liliaceae or at least in some species of genus Fritillaria. Obtained results support transcriptomics as useful approach in elucidating genes underlying complex biochemical pathways.