Garlic virus X 11-kDa protein granules move within the cytoplasm and traffic a host protein normally found in the nucleolus

Abstract

The subcellular localization of the 11-kDa protein (p11) encoded by ORF3 of Garlic virus X (GarVX; genus Allexivirus, family Alphaflexiviridae) was examined by confocal microscopy. Granules with intense fluorescence were visible on the endoplasmic reticulum when p11 fused with green or red fluorescent protein (GFP or RFP) was expressed in epidermal cells of Nicotiana benthamiana. Moreover, the p11-RFP granules moved in the cytoplasm, along the cell periphery and through the cell membranes to adjacent cells. A 17-kDa protein (p17) of garlic interacting with p11 was identified by yeast two-hybridization and bimolecular fluorescence complementation assay. When p17 fused to GFP was expressed in epidermal cells of N. benthamiana, it localized to the nucleolus. However, in the presence of GarVX p11, the distribution of p17 changed to that of p11, but did not appear to affect the pattern of movement of p11.