Metabolic engineering of volatile isoprenoids in grapevine

Grapevine deoxyxylulose phosphate synthase (VvDXS) was reported as a positional candidate gene for muscat flavor having been co-localized with a major QTL for monoterpenoids in berries. Recently a putative causal SNP responsible for a non-neutral substitution in the VvDXS1 protein was found to be significantly associated with muscat flavored varieties and a functional effect of this polymorphism was proven in transgenic tobacco adopting a reverse genetics approach. Here we aimed at applying the same strategy in grapevine in order to deeply investigate the metabolic changes induced by the overexpression of the mutated (M) or non mutated (nM) form of VvDXS1. Grapevine transgenic shoots were obtained and acclimatized in greenhouse. The expression pattern of VvDXS1 was evaluated in leaves of transgenic and wild type plants at different time points and the emission of volatile organic compounds (VOC) was assessed.