Gene suppression and metabolome change in camptothecin biosynthesis

Abstract

Camptothecin is produced in the hairy roots but not in cell suspension culture of Ophiorrhiza pumila. The hairy root specific metabolites were profiled by non-target analysis by using infusion FT-ICR-MS. Furthermore, the gene expression of two enzymes, triptophane decarboxylase (TDC) and secologanin synthase (SLS), involved in the biosynthetic pathway of indole alkaloids were modified by RNAi silencing. The metabolic changes in these hairy roots were analyzed by LC-FT-ICR-MS. From the exact mass of the ion peaks that changed correlatively with the suppressed gene expression, candidates of intermediates were predicted.