Use of an attenuated strain of tobamovirus for early detection of virus-induced gene silencing

Abstract

Virus-induced gene silencing (VIGS) can be used to study gene function by mediating sequence-specific mRNA degradation and suppressing the expression of endogenous target genes. We previously demonstrated that the TocJ vector based on the tomato mosaic tobamoviruses (ToMV) was able to multiply, spread systemically and express green fluorescence protein in Solanaceous plants. TocJ harbouring fragments of endogenous genes could induce VIGS of the parental gene expression, but also induced viral infection symptoms. In this study, an attenuated strain of ToMV, L11A, was used to construct a ToMV vector in order to reduce the virus- induced symptoms. This new vector, named LcJ, was able to spread systemically and mediated VIGS of endogenous genes without visible symptoms. We propose that the use of this attenuated strain for the construction of virus vectors is beneficial for the induction of VIGS.