Technical Advance: Tobacco rattle virus as a vector for analysis of gene function by silencing

TLDR

Virus vectors that carry host-derived inserts trigger gene silencing in infected plants, a form of RNA‑mediated defense related to post‑transcriptional gene silencing. The study aims to develop a modified TRV infectious cDNA clone that permits insertion of non‑viral sequences for plant infection. The authors engineered the TRV clone to enable host sequence insertion and subsequent infection of plants. The TRV vector effectively silences endogenous genes without symptoms, targets RNAs in growing points, and shows promise for broad gene discovery in plants.

Abstract

Summary Virus vectors carrying host‐derived sequence inserts induce silencing of the corresponding genes in infected plants. This virus‐induced gene silencing (VIGS) is a manifestation of an RNA‐mediated defence mechanism that is related to post‐transcriptional gene silencing (PTGS) in transgenic plants. Here we describe an infectious cDNA clone of tobacco rattle virus (TRV) that has been modified to facilitate insertion of non‐viral sequence and subsequent infection to plants. We show that this vector mediates VIGS of endogenous genes in the absence of virus‐induced symptoms. Unlike other RNA virus vectors that have been used previously for VIGS, the TRV construct is able to target host RNAs in the growing points of plants. These features indicate that the TRV vector will have wide application for gene discovery in plants.