The classic reverse genetic screening, such as EMS-induced or T-DNA-mediated mutation, is a powerful tool to identify senescence-related genes in many model plants. For most non-model plants, however, this strategy is hard to achieve. Even for model plants, construction of a mutant library is usually labor and time-consuming. Virus-induced gene silencing (VIGS) provides an alternative to characterize gene function in a wide spectrum of plants through transient gene expression. To date, more than a dozen of VIGS vector systems have been developed from different RNA and DNA viruses, while Tobacco rattle virus (TRV) system might be one of the most used due to its wide host range and ease of use. Here, we describe a modified TRV vector, TRV-GFP, in which a green fluorescent protein (GFP) is fused to 3'-end of the coat protein (CP) gene in the TRV2 vector. Since the GFP-tagged CP protein could be traced under UV light in planta, identification of TRV-GFP-infected plants is easy. Application of this system in identifying genes regulating petal senescence in rose is described.
Keywords: Functional analysis; Petal senescence; Rose; Vacuum infiltration; Virus-induced gene silencing; pTRV; pTRV-GFP.