Abstract
Double-stranded RNAs (DsRNAs) that contain a sequence homologous to the promoter sequence can be supplied to plant cells using a plant virus vector, which induce methylation on the promoter and subsequently induce repression of transcription, termed transcriptional gene silencing (TGS). We previously developed a plant virus vector based on the Cucumber mosaic virus (CMV), which is able to efficiently induce RdDM and TGS in plants.
To analyze the induction process of TGS, we cloned various portions of the CaMV 35S promoter sequence into the CMV vector, and inoculated the virus to Nicotiana benthamiana plants containing a single-copy GFP gene expressed under the control of the 35S promoter. We found that the efficiency of the induction of TGS depended on the length of the promoter segment triggering the RdDM, although the siRNAs corresponding to the 35S promoter accumulated to a similar level in TGS-induced and non-TGS induced plants.
