BACKGROUND Classical Swine Fever (CSFV) is one of the most important viral infectious diseases affecting wild boars and domestic pigs. The etiological agent of the disease is the CSF virus, a single stranded RNA virus belonging to the family Flaviviridae. All preventive measures in domestic pigs have been focused in interrupting the chain of infection and in avoiding the spread of CSFV within w...

Amplicon transgenes from potato virus X (PVX) are based on a modified version of the viral genome and are efficient activators of post-transcriptional gene silencing (PTGS). To determine whether PVX amplicons activate PTGS in Arabidopsis, we used constructs based on the genome of PVX carrying a green fluorescent protein (GFP) reporter gene. Our analysis of the transgene phenotype exploited prev...

Potato virus X multiplication as influenced by mineral nutritions of host has been studied by some workers (HELMS & POUND 1955, BAWD EN & KASSANIS 1950, GANGULI & al. 1963). They have mostly studied the effect of nitrogen, phosphorus and potassium nutrition on the host growth and virus multiplication. Host nutrition with magnesium in relation to PVX multiplication has not been much studied. The...

In plants, viruses induce an RNA-mediated defense that is similar to posttranscriptional gene silencing (PTGS) of transgenes. Here we demonstrate with potato virus X (PVX) that PTGS operates as a systemic, sequence-specific defense system. However, in grafting experiments or with movement defective forms of PVX, we could not detect systemic silencing unless the 25 kDa viral movement protein (p2...

Plant viruses use movement proteins (MPs) to modify intercellular pores called plasmodesmata (PD) to cross the plant cell wall. Many viruses encode a conserved set of three MPs, known as the triple gene block (TGB), typified by Potato virus X (PVX). In this paper, using live-cell imaging of viral RNA (vRNA) and virus-encoded proteins, we show that the TGB proteins have distinct functions during...

Background: Potato virus X has been developed into an expression vector for plants. It is widely used to express foreign genes. In molecular manipulation, the foreign genes need to be sub-cloned into the vector. The constructed plasmid needs to be amplified. Usually, during amplification stage, the foreign genes are not expressed. However, if the foreign gene is expressed, the construction work...

The nucleotide sequence of the genomic RNA of narcissus mosaic virus (NMV) was deduced from a set of cDNA clones and by direct sequencing of RNA. The genome, with a length of 6955 nucleotides [excluding the 3'poly(A) tail], contains six open reading frames (ORFs) with the capacity to code for polypeptides of more than 10K, with Mr values of 186284, 25845, 13998, 11059, 26097 and 10519. The firs...

Virus induced gene silencing (VIGS) is increasingly used to generate transient loss-of-function assays and has potential as a powerful reverse-genetics tool in functional genomic programs as a more rapid alternative to stable transformation. A previously described potato virus X (PVX) VIGS vector has been shown to trigger silencing in the permissive host Nicotiana benthamiana. This paper demons...

Double-stranded cDNA of potato virus X (PVX) genomic RNA has been cloned and sequenced. The sequence [6435 nucleotides excluding the poly(A) tract] revealed five open reading frames (ORFs) which were numbered one to five starting at the 5' terminus of the RNA. They encoded proteins of Mr 165588 (166K), 24622 (25K), 12324 (12K), 7595 (8K) and 25080 (coat protein), respectively. ORFs 1 and 2 were...