Grapevine virusA-mediated gene silencing in Nicotiana benthamiana and Vitis vinifera.

Virus-induced gene silencing (VIGS) is an attractive approach for studying gene function. Although the number of virus vectors available for use in VIGS experiments has increased in recent years, most of these vectors are applied in annual or herbaceous plants. The aim of this work was to develop a VIGS vector based on the Grapevine virus A (GVA), which is a member of the genus Vitivirus, family Flexiviridae. The GVA vector was used to silence the endogenous phytoene desaturase (PDS) gene in Nicotiana benthamiana plants. In addition, an Agrobacterium-mediated method for inoculating micropropagated Vitis vinifera cv. Prime plantlets via their roots was developed. Using this method, it was possible to silence the endogenous PDS gene in V. vinifera plantlets. The GVA-derived VIGS vector may constitute an important tool for improving functional genomics in V. vinifera.