Vindoline Biosynthesis Is Transcriptionally locked in Catharanthus roseus Cell Suspension Cultures

Abstract

Catharanthus roseus cell cultures were exposed to different conditions in order to induce alkaloid metabolism. The exposure to jasmonate and fungal elicitors resulted in the transcriptional activation of tryptophan decarboxylase and in the accumulation of the monoterpenoid indole alkaloids ajmalicine and catharanthine, but not of vindoline. The inability of the cell cultures to produce vindoline was related to a lack of expression of the desacetoxyvindoline 4-hydroxylase (D4h) gene. Southern blot analysis revealed that D4h gene was not lost in the cell cultures.

Gene-to-metabolite networks for terpenoid indole alkaloid biosynthesis in Catharanthus roseus cells

“…In agreement with ref. 19, later pathway genes such as D4H and DAT were not expressed under our experimental conditions, justifying the fact that vindoline does not accumulate in cell cultures despite the availability of precursor metabolites.…”

Enhancement of Vindoline Production in Suspension Culture of the Catharanthus roseus Cell Line C20hi by Light and Methyl Jasmonate Elicitation

“…7 Variations at gene transcription levels reflected an early regulatory step in a biosynthetic pathway; therefore, we first tested the transcription of t16h and d4h in C20hi cells after elicitation. As can be seen in Fig.…”

“…Thus, the lack of vindoline biosynthesis becomes the major obstacle of using cell cultures to produce vinblastine and vincristine. 2,6,7 However, vindoline biosynthesis was restored in shoots that regenerated from a non-producing callus and tabersonine precursor accumulated in cell cultures, indicating that vindoline may be acquired by fulfilling its regulatory requirements. 8,9 As illustrated in Fig.…”

“…It has been reported that d4h is transcriptionally blocked in C. roseus cell cultures, which may result in a failure of vindoline biosynthesis. 7 Therefore, external regulatory strategies activating d4h transcription may contribute to the accumulation of vindoline, where elicitation is a very promising strategy.…”

Simultaneous Quantification of Four Indole Alkaloids in Catharanthus roseus Cell Line C20hi by UPLC-MS

“…Catharanthine can be isolated at high levels from periwinkle cell cultures, but stable production of vindoline has not been observed in these culture systems. [7][8][9] It is therefore assumed that the major obstacle of using cell cultures to produce dimeric alkaloids lies in the inability of cell cultures to produce vindoline. 9 However, vindoline biosynthesis is restored in shoots that regenerated from a non-producing callus, 10 which indicates that vindoline biosynthesis may be unblocked in cell cultures by fulfilling its regulatory requirements.…”