Efficient gene silencing induction in tomato by a viral satellite DNA vector

Virus-induced gene silencing (VIGS) in tomato (Lycopersicon esculentum Mill.) is currently routinely analysed using Tobacco rattle virus (TRV)-based vector. We recently reported a new vector system modified from DNAβ (DNAmβ) of Tomato yellow leaf curl China virus (TYLCCNV) for VIGS analysis in Solanaceousspecies including tomato. Here, we describe DNAmβ-induced gene silencing in tomato. We found that DNAmβ-induced gene silencing was initiated from vascular tissues, and later scattered to other tissues. Once initiated in seedlings, the silencing phenotype lasted for the entire life span of the plants, was expressed in a variety of tissues and organs including leaf, shoot, stem, flower and fruit, and could be achieved at any growth stage. It was insensitive to temperature as high as 32 °C and no symptoms were observed in silenced plants. The DNAmβ vector worked efficiently in at least seven tomato cultivars, indicating that this system has great potential as a versatile VIGS system for routine functional analysis of genes in tomato.