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Background: The medicinal plant, Catharanthus roseus (C. roseus), accumulates a wide range of terpenoid indole alkaloids (TIAs). Ethylene (ET) and methyl-jasmonate (MeJA) were previously reported as effective elicitors for the production of various valuable secondary metabolites of C. roseus, while a few ET or MeJA induced transcriptomic research is yet reported on this species. In this study, the de-novo transcriptome assembly of C. roseus is performed by using the next-generation sequencing technology. Results: The result shows that phenolic biosynthesis genes respond specifically to ET in leaves, monoterpenoid biosynthesis genes respond specifically to MeJA in roots. By screening the database, 23 ATP-binding cassette (ABC) transporter partial sequences are identified in C. roseus. On this basis, more than 80 key genes that encode key enzymes (namely TIA pathway, transcriptional factor (TF) and candidate ABC transporter) of alkaloid synthesis in TIA biosynthetic pathways are chosen to explore the integrative responses to ET and MeJA at the transcriptional level. Our data indicated that TIA accumulation is strictly regulated by the TF ethylene responsive factor (ERF) and bHLH iridoid synthesis 1 (BIS1). The heatmap, combined with principal component analysis (PCA) of C. roseus, shows that ERF co-expression with ABC2 and ABC8 specific expression in roots affect the root-specific accumulation of vinblastine in C. roseus. On the contrast, BIS1 activities follow a similar pattern of ABC3 and CrTPT2 specific expression in leaves, which affects the leaf-specific accumulation of vindoline in C. roseus. Conclusions: Results presented above illustrate that ethylene has a stronger effect than MeJA on TIA induction at both transcriptional and metabolite level. Furthermore, meta-analysis reveals that ERF and BIS1 form a positive feedback loop connecting two ABC transporters respectively and are actively involved in TIAs responding to ET and MeJA in C. roseus. [ABSTRACT FROM AUTHOR]

We selected different concentrations of ethephon, to stress C. roseus. We used qRT-PCR and HPLC followed by PCA to obtain comprehensive profiling of the vinblastine biosynthesis in response to ethephon. Based on our findings, the results showed that the high concentration of ethephon had a positive effect at both transcriptional and metabolite level. Meanwhile, there was a remarkable decrease of hydrogen peroxide content and a promoted peroxidase activity in leaves. The loading plot combination with correlation analysis suggested that CrPrx1 could be regarded as a positive regulator and interacts with ethylene response factor (ERF) to play a key role in vinblastine content and peroxidase (POD) activity. This study provides the foundation for a better understanding of the regulation and accumulation of vinblastine in response to ethephon. [ABSTRACT FROM AUTHOR]

Many plants in the family Apocynaceae have been used for medicinal purposes.Catharanthus roseusandVinca minorare the most important medicinal plants that belong to the Apocynaceae family. A procedure is reported for the determination of the bioactive alkaloids tabersonine, serpentine, vindoline, catharanthine, tryptamine, and vincamine in Apocynaceae plants (C. roseusandV. minor) by liquid chromatography electrospray ionization tandem mass spectrometry. Quantitation was performed from positive multiple reactions at 161.4 → 144.2, 349.4 → 263.0, 457.6 → 188.0, 337.5 → 168.3, 337.4 → 144.2, 355.4 → 337.2, and 854.5 → 286.4 for tryptamine, serpentine, vindoline, tabersonine, catharanthine, vincamine, and paclitaxel (the internal standard), respectively. The optimized method was employed for the determination of the active alkaloids in the leaves ofC. roseusandV. minorby liquid chromatography–tandem mass spectrometry. [ABSTRACT FROM PUBLISHER]