Mechanism Of Jasmonic Acids Involved In The Regulation Of TIA Biosynthesis In Catharanthus Roseus

Terpenoid Indole Alkaloids?TIAs?have particular and considerable medical properties,especially in the treatment of cancer.The unique commercial source of TIAs is the Madagascar periwinkle {Catharanthzus roseus?L.?G Don)which can produce more than 150 alkaloids,including the effective antitumor drugs,vinblastine,and vincristine.To date,many studies have found that jasmonic acid could participate in the biosynthesis process of TIA.However,most studies focused on single or several genes,and mainly focused on the transcriptional level and metabolic level.Therefore,to provide the theory support for TIA production increase,this study aims to explore the molecular mechanism of jasmonic acid in regulating TIA synthesis in C.roseus.MOmicsn based study was of great significance for the in-depth understanding of the response mechanism of TIAs under jasmonic acid treatment at transcriptional,translation,and metabolic levels,respectively.At the transcriptional level,the monoterpenoid biosynthesis genes showed particular sensitivity when stimulated by jasmonic acid under KEGG pathway enrichment analysis.We found that the upstream of TIA pathway genes were more sensitive to jasmonic acid in roots by qRT-PCR.A total of 2011 transcription factors were found in C.roseus.Through correlation and heatmap analyses,an AP2/ERF transcription factor?designated as CrERF1?was discovered.Subcellular colocalization demonstrated that CrERF1 was located in the nucleus.Dual-LUC promoter analysis found that CrERF1 was able to activate the strictosidine synthase?STR?promoter which is the core regulator gene of the TIA pathway and enhance the expression of STR.In addition to responding positively to jasmonic acid,it was interested to find that CrERF1 and CrORCA2 were highly expressed under heat stress.Jasmonic acid and heat stress may regulate the expression of CrERF1 and then regulate the STR.Correlation analysis indicated that CrERF1 co-expressed with CRO₁19553,and CrORCA2 showed a similar expression pattern with CRO₁14609 involving in the biosynthesis and transportation of the tryptamine actively.CRO₁16588 is one of the ABC family transporter,which is specifically expressed in the root,and it probably involved in the transport and accumulation of ajmalicine actively.At the metabolism level,we compared the effects of various hormones on TIAs production.The results showed that jasmonic acid could promote the production of tabersonine dramatically?6 folds?.Meanwhile,it's found that vinblastine,the essential medicine composition for curing cancer,responded to jasmonic acid actively on production.The metabolomic analysis also found that jasmonic acid can significantly improve the biosynthesis of the metabolites in the vindoline and vinblastine pathways.At the translation level,we used polysome profiling to find the difference of TIA pathway genes in response to jasmonic acid and ACC.We found that the TIA pathway genes were down-regulated in response to ACC;in contrast,the TIA pathway genes were responded positively to jasmonic acid treatment.The translation of the PRX gene was remarkably up-regulated by jasmonic acid induction.There was no significant change in PRX at the transcription level in response to jasmonic acid.Our results showed that jasmonic acid enhances the production of vinblastine mainly by improving the translation level of PRX.To sum up,this study compared the biosynthesis of TIAs in responses to various hormones at the transcription,translation,and metabolic processes.Phytohormone jasmonic acid is actively involved in the regulation of the biosynthesis process of TIA in C.roseus from multiple aspects.Jasmonic acid can directly regulate the translation of PRX to affect the synthesis of vinblastine,or indirectly through the regulation of the expression of transcription factors and transporters,thereby affecting the expression of TIA pathway genes and the transportation of alkaloids.