Andrographis paniculata transcriptome provides molecular insights into tissue-specific accumulation of medicinal diterpenes

• DOI: 10.1186/s12864-015-1864-y
• Publication Date: 2015-09-01T12:42:27Z
• Authors: Anchal Garg; Lalit Agrawal; Rajesh Chandra Misra; Shubha Sharma; Sumit Ghosh
• Keywords: KEGG; Andrographis Paniculata

Kalmegh (Andrographis paniculata) has been widely exploited in traditional medicine for the treatment of infectious diseases and health disorders. Ent-labdane-related diterpene (ent-LRD) specialized (i.e., secondary) metabolites kalmegh such as andrographolide, neoandrographolide 14-deoxy-11,12-didehydroandrographolide, are known variety pharmacological activities. However, due to lack genomic transcriptomic information, underlying molecular basis ent-LRDs biosynthesis remained largely unknown. To identify candidate genes ent-LRD biosynthetic pathway, we performed comparative transcriptome analysis using leaf root tissues that differentially accumulate ent-LRDs.De novo assembly Illumina HiSeq2000 platform-generated paired-end sequencing reads resulted into 69,011 64,244 transcripts which were assembled a total 84,628 unique transcripts. Annotation these Uniprot, Kyoto Encyclopedia Genes Genomes (KEGG) Carbohydrate-Active Enzymes (CAZy) databases identified pathway. These included encode enzymes plastidial 2C-methyl-D-erythritol-4-phosphate pathway provides C5 isoprenoid precursors biosynthesis, geranylgeranyl diphosphate synthase, class II synthase (diTPS), cytochrome P450 monooxygenase glycosyltransferase. Three diTPSs (ApCPS1, ApCPS2 ApCPS3) showed distinct tissue-specific expression profiles phylogenetically related dicotyledon ent-copalyl synthases, identified. ApCPS1, ApCPS3 832-, 817- 797- amino acids proteins 55-63 % identity, respectively. Spatio-temporal patterns accumulation consistent with involvement ApCPS1 general primary) metabolism phytohormone gibberellin, biosynthesis. Moreover, simple sequence repeats (SSRs) might assist genotyping developing specific chemotypes metabolic pathways, including ent-LRDs.Comparative transcriptomes disclosed novel three discrete spatio-temporal patterns; thus, suggesting their participation pathways kalmegh. Overall, results will be useful understanding medicinal breeding strategies improving yields.