The p27 open reading frame of tomato infectious chlorosis virus encodes a suppressor of RNA silencing

Tomato infectious chlorosis virus (TICV) belongs to the genus Crinivirus in the family Closteroviridae . We used Agrobacterium co-infiltration leaf patch assays to investigate the suppression of RNA silencing by p27, which is encoded by TICV-RNA1 ORF2 in a genomic location similar to that of viral suppressor of RNA silencing (VSR) ORF in other criniviruses. Additionally, Nicotiana benthamiana was inoculated with a potato virus X vector (pGR106) carrying the p27 sequence (pGR106–p27) to examine whether p27 is a VSR. Plants infiltrated with pGR106–p27 exhibited more severe necrosis and mosaic symptoms. This is the first report describing a TICV VSR.