The cuticle protein MPCP2 is involved in Potato virus Y transmission in the green peach aphid Myzus persicae

Abstract

Potato virus Y (PVY) is a destructive and widespread virus in a number of important crops, including potato. Aphid vectors spread this viral infection between plants in a non-persistent manner, and the green peach aphid (Myzus persicae) is the most efficient known vector. In this research, we investigated five cuticle proteins (CuPs) which are expected to be involved in virus transmission at the stylet of aphids. In an RNA interference (RNAi) gene-silencing assay with the green peach aphids (M. persicae), we evaluated the impact of these CuPs on the transmission of PVY with potato and tobacco plants. Using an oral RNAi bioassay where the aphids pierce-suck in an artificial diet that was supplemented with gene-specific dsRNA, the expression of only two CuPs, mpcp2 (DQ108935) and mpcp1 (AF435075.1), could be decreased by 63 and 75%, respectively. Expression of the other three CuPs could not be affected. Subsequently, we investigated what the effect is of the RNAi-mediated gene silencing on the transmission of PVY from potato to tobacco plants. These results showed with a high certainty of 99.5%, for the first time in vivo, a significant involvement of MPCP2 with a reduction of 47% (compared to the dsGFP control) in the transmission of PVY. For MPCP1, the effect was smaller with a reduction of 19% and lower certainty of 86%.