Styrax japonicus functional genomics: an efficient virus induced gene silencing (VIGS) system

VIGS (Virus-induced gene silencing), a method for posttranscriptional gene silencing, is an effective technique for investigating the activities of genes in plants. Since there is no report for available VIGS system in Styrax japonicus, the application of a VIGS approach that results in a gene knockdown to study gene function is limited. In this study, we compared the characteristics that could affect the viability of VIGS in S. japonicus, including the acetosyringone (AS) concentration, the Agrobacterium's optical density and the inoculation method. The stable reference genes of S. japonicus were selected to validate the gene's knockdown by quantitative PCR. As a result, we successfully constructed 2 VIGS systems based on TRV virus: vacuum with AS concentration of 200 μmol·L−1 and OD600 of 0.5, and friction-osmosis with AS concentration of 200 μmol·L−1 and OD600 of 1.0, which silencing efficiency was 83.33% and 74.19%, respectively. The successfully applied VIGS method provides a rapid and effective reverse gene functional analysis approach in S. japonicus to identify unknown gene functions.