Transcriptome-based approach for gene discovery and metabolic engineering of camptothecin biosynthesis in Nothopodytes nimmoniana Graham.

Nothapodytes nimmoniana (J.Graham) Mabb.(Icacinaceae),an important source of monoterpene indole alkaloid, camptothecin(CPT). Primary cellular target of CPT is DNA topoisomerase I (topo I). However, number of reports have indicated its therapeutic potential against colon cancer , uterine cervical cancer, ovarian cancer, AIDS and malaria . Two clinically used anti-tumor compounds, topotecan and irinotecan, are currently semi-synthesized using natural camptothecins. Biosynthetic pathway of CPT is yet to be fully enunciated. Transcriptome analysis offers a powerful platform for pathway elucidation and determining the expression profile of genes involved in CPT biosynthesis at the molecular level.