Stilbene accumulation in cell cultures of Vitis amurensis Rupr. overexpressing VaSTS1, VaSTS2, and VaSTS7 genes

Stilbenes (resveratrol, piceid, viniferins, etc.) are acting as phytoalexins and possess valuable biologically active properties. To improve stilbene production in grapevine, the effect of VaSTS1, VaSTS2, and VaSTS7 gene overexpression on stilbene production in callus cell cultures of wild grapevine Vitis amurensis Rupr. were accessed. Overexpression of VaSTS1 increased the total content of stilbenes by 1.2-2.1 times up to 0.36 mg per g of the dry weight (mg g(-1) dry wt) or 0.036 % of dry wt, while overexpression of VaSTS2 and VaSTS7 increased the content of stilbenes by 1.5-3.5 and 2.5-2.8 times (up to 0.48 and 0.60 mg g(-1) dry wt), respectively. P-coumaric acid (CA), a precursor of stilbenes, induced stilbene content and production in all cell lines with the highest positive effect on stilbene accumulation being observed in the STS2- and STS7-transgenic cell lines. After the CA feeding, the stilbene content increased up to 1.09-1.16 mg g(-1) dry wt in the STS2- and one STS7-transgenic cell lines and only up to 0.35 and 0.40 mg g(-1) dry wt in the control and STS1-transgenic cell lines, respectively. Thus, overexpression of VaSTS1, VaSTS2, and VaSTS7 genes had a positive effect on stilbene accumulation in the cells of V. amurensis cultivated in vitro. T-resveratrol and t-resveratrol glycosides were the prevalent stilbenes synthesized in the STS-transgenic calli before and after CA feeding. The results obtained are innovative for plant biotechnology, since stilbene production in plant cell cultures overexpressing a STS gene has not been studied until now.