The replication of many RNA viruses involves the translation polyproteins, whose processing by endopeptidases is a critical step for release functional subunits. P1 first protease encoded in plant potyvirus genomes; once activated an as-yet-unknown host factor, it acts cis on its own C-terminal end, hydrolyzing P1-HCPro junction. Earlier research suggests that cooperates with HCPro to inhibit silencing defenses. Using Plum pox virus as model, we show although does not have major direct role...

Since the discovery of microRNA (miRNA)-guided processing, a new type RNA silencing, possibility that such mechanism could play role in virus defense has been proposed. In this work, we have analyzed whether Plum pox (PPV) chimeras bearing miRNA target sequences (miR171, miR167, and miR159), which reported to be functional Arabidopsis, were affected by function three different host plants. Some these PPV had clearly impaired infectivity compared with those carrying nonfunctional sequences....

Improved plants are necessary to meet human needs. Agrobacterium-mediated transformation is the most common method used rewire plant capabilities. For gene delivery, DNA constructs assembled into binary T-DNA vectors that rely on broad host range origins for bacterial replication. Here we present pLX vectors, a set of mini plasmids suitable Type IIS restriction endonuclease- and overlap-based assembly methods. include replicons from compatible plasmids. Simultaneous usage pBBR1- RK2-based in...

African swine fever virus (ASFV) is a complex DNA that employs polyprotein processing at Gly-Gly-Xaa sites as strategy to produce several major core components of the viral particle. The gene S273R encodes 31-kDa protein contains "core domain" with conserved catalytic residues characteristic SUMO-1-specific proteases and adenovirus protease. Using COS cell expression system, it was found pS273R capable cleaving polyproteins pp62 pp220 in specific way giving rise same intermediates mature...

ABSTRACT Plum pox virus (PPV) is a member of the Potyvirus genus that, in nature, infects trees Prunus genus. Although PPV systemically several species Nicotiana genus, such as N. clevelandii and benthamiana , replicates inoculated leaves tabacum it unable to infect last host. The long-distance movement defect was corrected transgenic tobacco plants expressing 5"-terminal region genome etch (TEV), potyvirus that tobacco. fact move upper noninoculated transformed with same TEV transgene, but...

Polyprotein processing is a common strategy of gene expression in many positive-strand RNA viruses and retroviruses but not DNA viruses. African swine fever virus (ASFV) an exception because it encodes polyprotein, named pp220, to produce several major components the particle, proteins p150, p37, p34, p14. In this study, we analyzed assembly pathway ASFV contribution polyprotein products structure. Electron microscopic studies revealed that virions assemble from membranous structures present...

During the cytoplasmic maturation of African swine fever virus (ASFV) within viral factories, DNA-containing core becomes wrapped by two shells, an inner lipid envelope and outer icosahedral capsid. We have previously shown that is derived from precursor membrane-like structures on which capsid layer progressively assembled. In present work, we analyzed origin these membranes mechanism envelopment ASFV. Electron microscopy studies permeabilized infected cells revealed presence tightly...

Plum pox virus (PPV) is a member of the genus Potyvirus that able to infect large variety plant species, including trees Prunus, its natural host. When some PPV isolates are propagated for an extended time in herbaceous plants, their ability reduced. The molecular basis this change host infectivity poorly understood. We report construction hybrid viruses from cDNA clones two D-strain PPV, PPV-D and PPV-R, which differ range. can GF305 peach seedlings efficiently, however, it unable Nicotiana...

Breeding for disease-resistant crops is essential to ensure global food security. Traditional crop breeding, while widely accepted, time-consuming and always hampered by the scarcity of resistance sources. Although customizing disease has been a long-cherished dream breeders, data few successful examples are available. Recent advances in plant immune mechanisms have made it possible genetically engineer effector binding interface intracellular nucleotide-binding leucine-rich repeat (NLR)...

RNA silencing has a well-established function as an antiviral defence mechanism in plants and insects. Using Agrobacterium-mediated transient assay, we report here that NS1 protein from human influenza A virus suppresses manner similar to P1/HC-Pro of Tobacco etch potyvirus, well-characterized plant suppressor. Moreover, have shown expression strongly enhances the symptoms Potato X three different hosts, suggesting could be inhibiting mechanisms activated on infection. These data provide...

SUMMARY The potyviruses Plum pox virus (PPV) and Tobacco vein mottling (TVMV) have distinct host ranges induce different symptoms in their common herbaceous hosts. To test the relevance of P1 protein compatibility pathogenicity, hybrid viruses were constructed which coding sequence PPV was completely or partially replaced by corresponding sequences from TVMV. Infections induced these chimeric revealed that TVMV a PPV/TVMV proteins are functionally equivalent plants to isolate adapted hosts,...

SUMMARY Subisolates segregated from an M‐type Plum pox virus (PPV) isolate, PPV‐PS, differ widely in pathogenicity despite their high degree of sequence similarity. A single amino acid substitution, K109E, the helper component proteinase (HCPro) protein PPV caused a significant enhancement symptom severity herbaceous hosts, and notably modified infectivity peach seedlings. The presence this substitution certain subisolates that induced mild symptoms hosts did not infect seedlings suggested...

Plum pox virus (PPV)-D and PPV-R are two isolates from strain D of PPV that differ in host specificity. Previous analyses chimeras originating PPV-D suggested the N terminus coat protein (CP) includes host-specific pathogenicity determinants. Here, these determinants were mapped precisely by analyzing infectivity herbaceous woody species containing a fragment 3' region (including coding for CP) backbone. These not infectious Prunus persica, but systemically infected Nicotiana clevelandii N....

Fluorescent proteins are extraordinary tools for biology studies due to their versatility; they used extensively improve comprehension of plant-microbe interactions. The viral infection process can easily be tracked and imaged in a plant with fluorescent protein-tagged viruses. In plants, protein genes among the most commonly reporters transient RNA silencing heterologous expression assays. Fluorescence intensity is quantify accumulation by image analysis or spectroscopy extracts; however,...

Three African swine fever virus structural proteins of relative molecular weights 150,000, 37,000, and 34,000 (p150, p37, p34) are derived from precursors with 220,000,60,000, 39,000 (pp220, pp60, pp39) by proteolytic cleavage after the second Gly residue in sequence Gly-Gly-Ala/Gly.A search National Biomedical Research Foundation Data Bank revealed that several adenovirus proteins, ubiquitin, an interferon-induced 15-kDa protein also cleaved at Gly-Gly-X, where X is often amino acid a...

Serine and threonine of many nuclear cytoplasmic proteins are posttranslationally modified with O-linked N-acetylglucosamine (O-GlcNAc). This modification is made by transferases (OGTs). Genetic biochemical data have demonstrated the existence two OGTs Arabidopsis thaliana, SECRET AGENT (SEC) SPINDLY (SPY), at least partly overlapping functions, but there little information on their target proteins. The N terminus capsid protein (CP) Plum pox virus (PPV) isolated from Nicotiana clevelandii...

Rhodococcus fascians is currently the only phytopathogen of which virulence genes occur on a linear plasmid. To get insight into origin this replicon and strategy broad-spectrum phytopathogen, sequence plasmid strain D188, pFiD188, was determined. Analysis 198,917 bp revealed four syntenic regions with plasmids R. erythropolis, jostii, opacus, suggesting common these replicons. Mutational analysis pFi_086 pFi_102, similar to cutinases type IV peptidases, respectively, showed that conserved...

The Potyviridae family is a major group of plant viruses that includes c. 200 species, most which have narrow host ranges. potyvirid P1 leader proteinase self-cleaves from the remainder viral polyprotein and shows large sequence variability linked to adaptation. proteins can be classified as Type A or B on basis, amongst other things, their dependence not factor develop protease activity. In this work, we studied proteases family, characterizing requirements. Our in vitro cleavage analyses...

We have identified an open reading frame (ORF), CP530R, within the EcoRI C' fragment of African swine fever virus (ASFV) genome that encodes a polyprotein 62 kDa (pp62). Antisera raised against different regions ORF CP530R recognized polypeptide in ASFV-infected cells during late phase replication, after onset viral DNA synthesis. Pulse-chase experiments showed pp62 is posttranslationally processed to give rise two proteins 35 (p35) and 15 (p15). This proteolytic processing was found take...