A new strategy to enhance the biosynthesis of trans-resveratrol by overexpressing stilbene synthase gene in elicited Vitis vinifera cell cultures

In this work, transgenic lines of suspension cultured cells of Vitis vinifera cv. Monastrell containing the plasmid pMOG800-sts have been obtained. The cell growth of these transgenic cell lines decreased slightly as compared to non-transgenic suspension cultured cells, while cell viability was not affected. In addition, the elicitation with cyclodextrins and methyl jasmonate enhanced the production of transresveratrol, observing the highest levels of this compound in sts-expressing transgenic Vitis suspension cultured cells with the sts expression cassette in the forwards orientation. Moreover, the forwards 2 (F2) transgenic cell line produced the greater levels of trans-resveratrol in comparison with the nontransgenic cell line. In fact, when suspension cultured cells were treated with both elicitors, the accumulation of trans-resveratrol outside the cells in the F2 transgenic suspension cultured cells increased twice (1458 mg.L-1) as compared to non-transgenic cell lines (724 mg.L-1). In both cases, the levels of trans-resveratrol detected in the treatment with cyclodextrins and methyl jasmonate were greater than the sum of the individual treatments, and therefore we observed a synergistic effect in the presence of both elicitors. Moreover, the expression profile of sts gene in transgenic V vinifera cell lines was similar to the expression profile detected for the endogenous sts gene in non-transgenic V vinifera cell lines, being the expression levels greater in the treatment with methyl jasmonate and cyclodextrins, which was related to the high levels of trans-resveratrol found in the presence of both elicitors. (C) 2017 Elsevier Masson SAS. All rights reserved.