Isolation of Δ5-3β-hydroxysteroid dehydrogenase involved in the biosynthetic pathway of cardenolides and its expression level under the influence of salicylic acid and methyl jasmonate elicitors in foxglove (Digitalis nervosa L)

Foxglove plants are important sources of medicinal cardiac glycosides compounds such as digoxin and digitoxin, which are used for treatment of congestive heart failure and cardiac arrhythmia. Digitalis has several valuable species but the only species native to Iran is digitalis nervosa. Considering the importance of study on native plants in order to be used in pharmaceutical industry this research was carried out. One of the key genes in the biosynthesis of digitalis cardenolide in plants is 3β-HSD, which encodes the enzyme 3β-HSD with important role in early stage of the cardenolide biosynthesis pathway. Purpose of the present study was to determine nucleotide sequence of 3β-HSD, phylogenetic analyses and its expression under influence of salicylic acid and methyl jasmonate elicitors in different tissues. Results revealed that a sequence encoding the enzyme show very close affinity to Digitalis lanata. In addition expression pattern of 3β-HSD in the transcript level revealed that a significant expression level was detected in leaf tissue, and also under treatment of methyl jasmonate and salicylic acid the expression level raised. Findings of our study could be used to increase cardenolide through metabolic engineering and genetic manipulation.