The effect of method of purification and incubation with trypsin on the amino acid composition and molecular weight of potato virus X (PVX) protein was determined. PVX wae prepared by four methods, two of which included incubation of unclarified plant sap at room temperature for 24 hr before addition of organic solvents. The molecular weights of the proteins of PVX determined by SDS polyacrylam...

ABSTRACT The expression of a gene that encodes coat protein (CP) of Potato virus X (PVX) in transgenic tobacco plants confers a high level of CP-mediated rresistance (CP-MR) against PVX infection. To determine if posttranscriptional gene silencing (PTGS) plays a role in resistance, transgenic plants expressing PVX CP were challenged against PVX under conditions in which PTGS was suppressed by l...

Because viruses encode only a small number of proteins, all steps of virus infection rely on specific interactions between viruses and hosts. We previously screened several Nicotiana benthamiana (Nb) proteins that interact with the stem-loop 1 (SL1) RNA structure located at the 5' end of the potato virus X (PVX) genome. In this study, we characterized two of these proteins (NbCPIP2a and NbCPIP2...

Tobacco plants were transformed with constructs in which the transgene was a cDNA of replicating potato virus X (PVX) RNA. The constructs, referred to here as amplicons, were the intact genome of PVX and PVX constructs modified to carry the beta-glucuronidase (GUS) reporter gene either as an additional gene or as a replacement for the coat protein gene (PVX/GUS/CP and PVX/GUS respectively). Tra...

We have generated hybrid chimeric potato virus X (PVX) particles by coexpression of different PVX coat protein fusions utilizing tobacco mosaic virus (TMV) and PVX-based expression vectors. Coinfection was achieved with a modified PVX overcoat vector displaying a fluorescent protein and a TMV vector expressing another PVX fluorescent overcoat fusion protein. Coexpression of the PVX-CP fusions i...

Potato virus X (PVX; genus Potexvirus, family Alphaflexiviridae, order Tymovirales) is one of the most widespread and intensively studied viruses of potato. However, little is known about its diversity in its likely center of radiation, the Andean region of South America. To fill this gap, the strategy of Illumina deep sequencing of small RNAs was used to obtain complete or near complete genome...

The first open reading frame (ORF 1) of potato virus X (PVX) encodes a putative replicase gene. Transgenic tobacco lines expressing ORF 1 are resistant to PVX infection when inoculated with either PVX or PVX RNA. Analyses of lines containing various portions of the ORF 1 gene demonstrated that resistance is conferred to plants by expressing approximately the first half of the ORF 1 gene. One li...