Virus survival of RNA silencing without deploying protein-mediated suppression in Nicotiana benthamiana.

RNA silencing represents an evolutionarily conserved defence mechanism that plays a key antiviral role in protecting plants and animals against virus infection. To counterattack, plant, animal and fungal viruses produce proteins capable of suppressing RNA silencing. Here, we report an unprecedented phenomenon that Potato virus X, a single-stranded positive RNA virus, is able to survive RNA silencing without deploying protein-mediated anti-silencing by revealing an unexpected symptom re-emergence and re-accumulation of viral RNAs and proteins in plants maintaining strong RNA silencing. Our results provide evidence that a plant virus may have developed a getaway strategy to survive RNA silencing.