Role of the 5' untranslated region of the Alfalfa mosaic virus RNA 3 in cell-to-cell and long distance transport.

Após o início da infecção de uma única célula, vírus de planta necessita para invadir as células adjacentes, uma processo de transporte de célula-a-célula denominados, como um passo anterior para invadir as partes distais do hospedeiro através do sistema vascular ou do transporte sistémico. A capacidade para atingir as partes não inoculadas de um planta implica que o vírus deve infectar específico células localizadas no tecido vascular. Na maioria dos casos, partículas do vírus são necessários para este trans- vascular port. No presente estudo, tratamos o caracterização de determinantes virais críticos para o transporte de longa distância usando o Alfalfa vírus do mosaico (AMV) sistema de modelo, o que exige partícula do vírus para o transporte sistêmicaEdição dos Resumos do 12º Congreso Nacional de Virología, Burgos, Espanha, jun. 2013

Simultaneous detection of the 13 viruses and 5 viroids affecting grapevine by molecular hybridization using a unique probe or 'polyprobe'.

Grapevine is the most economically important fruit crop in the world, which is affected by various diseases of viral and/or viroidal etiology, which may affect the production of grapes with losses of up to 15% (Martelli, 1993)

Pigmented purpuric dermatosis: a review of the literature

The pigmented purpuric dermatoses (PPDs) are a group of benign, chronic diseases. The variants described to date represent different clinical presentations of the same entity, all having similar histopathologic characteristics. We provide an overview of the most common PPDs and describe their clinical, dermatopathologic, and epiluminescence features. PPDs are both rare and benign, and this, together with an as yet poor understanding of the pathogenic mechanisms involved, means that no standardized treatments exist. We review the treatments described to date. However, because most of the descriptions are based on isolated cases or small series, there is insufficient evidence to support the use of any of these treatments as first-line therapy

A Preliminary Account on the Sanitary Status of Stone Fruits at the Clonal Genebank in Harrow, Canada

Field observations and laboratory tests were carried out in Harrow to evaluate the sanitary status of the Clonal Genebank collection of stone fruit. The presence of viruses and viroids was determined by ELISA, tissueprinting hybridization and GF305 woody indexing. A total of 645 trees (197 peach and nectarine, 183 sweet and sour cherries, 106 plum, 106 apricot, and 53 other cherries) were tested by ELISA for the presence of Plum pox virus (PPV), Prunus necrotic ring spot virus (PNRSV) and Prune dwarf virus (PDV). No evidence of PPV infection was found in the collection. PNRSV and PDV were frequently detected in single and mixed infections. The overall average of virus infection rate was 20.3%. A total of 336 trees (116 peach and nectarine, 84 sweet and sour cherries, 54 plum, 44 apricot, and 38 other cherries) were tested by tissue printing hybridization for the presence of Peach latent mosaic viroid (PLMVd) and Hop stunt viroid (HSVd). Thirty samples were infected, 28 peaches and nectarines with PLMVd and 2 apricots with HSVd. This is the first report to date, of HSVd presence in Canada. Finally, 114 (38.4%) out of 297 tested accessions were found infected with at least one virus and/or viroid

Systemic transport of Alfalfa mosaic virus can be mediated by the movement proteins of several viruses assigned to five genera of the 30K family

We previously showed that the movement protein (MP) gene of Alfalfa mosaic virus (AMV) is functionally exchangeable for the cell-to-cell transport of the corresponding genes of Tobacco mosaic virus (TMV), Brome mosaic virus, Prunus necrotic ringspot virus, Cucumber mosaic virus and Cowpea mosaic virus. We have analysed the capacity of the heterologous MPs to systemically transport the corresponding chimeric AMV genome. All MPs were competent in systemic transport but required the fusion at their C terminus of the coat protein-interacting C-terminal 44 aa (A44) of the AMV MP. Except for the TMV MP, the presence of the hybrid virus in upper leaves correlated with the capacity to move locally. These results suggest that all the MPs assigned to the 30K superfamily should be exchangeable not only for local virus movement but also for systemic transport when the A44 fragment is present.We thank L. Corachan for her excellent technical assistance. This work was supported by the Spanish granting agency DGICYT via grant BIO2011-25018 and by the Generalitat Valenciana via grant PROMETEO 2011-003.Fajardo, TVM.; Peiró Morell, A.; Pallás Benet, V.; Sanchez Navarro, JA. (2013). Systemic transport of Alfalfa mosaic virus can be mediated by the movement proteins of several viruses assigned to five genera of the 30K family. Journal of General Virology. 94:677-681. https://doi.org/10.1099/vir.0.048793-0S6776819

Tracking Plum pox virus in Chile throughout the year by three different methods and molecular characterization of Chilean isolates

During 2007, a survey was performed to detect and identify Plum pox virus (PPV) in Chilean stone fruit commercial orchards. A total of 1396 trees were analyzed and 45 (3.22 %) of them resulted positive. A fragment of 467 bp, corresponding to the replicase-coat protein (Nib-CP) region from the virus genome, was amplified and the the sequences obtained permitted the characterization of all isolates as PPV-D type, confirming that, so far, this is the only serotype present in Chile. To optimize virus detection, 27 PPV-positive trees were selected and sampled monthly from December 2006 until December 2007, collecting plant tissues available at the time of sampling (leaves, cuttings, buds and flowers). Each sample was analyzed by three different techniques: DASI-ELISA, RT-PCR and non-isotopic molecular hybridization (MH). The results showed that RT-PCR was more sensitive for detection in all months excepting January 2007, when the three techniques showed the same sensitivity. In general, MH showed a better sensitivity compared with DASI-ELISA. The best plant materials for analysis were: leaves, in February, March, September and October; phloem from cuttings in June; buds in July, and flowers in August. Keywords: PPV, detection, phylogeny, samplin

Phosphate recovery from treated municipal wastewater using hybrid anion exchangers containing hydrated ferric oxide nanoparticles

BACKDROUND This study presents the evaluation of two ion exchangers (granular and fibrous) impregnated with nanoparticles of hydrated ferric oxide (HFO) as selective sorbents for phosphate recovery from aqueous solutions. The hybrid impregnated anion exchangers combine the durability and mechanical strength of a polymeric weak base anion exchange resin with the high sorption affinity of HFO towards phosphate species. Dynamic experiments were carried out and data obtained were fitted to a well-known fixed-bed sorption model. RESULTS The theoretical sorption capacities reported by the Thomas model were in good agreement with the breakthrough experimental capacities determined from the sorption data. The sorption capacity decreased when using wastewater treatment plant secondary effluents in comparison with synthetic water mainly owing to the presence of organic matter and suspended solids. The phosphate sorbed on the impregnated ion exchangers was efficiently desorbed by using a 0.5 mol L-1 sodium hydroxide solution, reporting up to 90% of recovery. CONCLUSION The reusability of sorbents was evaluated through five sorption–desorption working cycles. Fiban-As was able to operate up to three consecutive cycles with good sorption performance while a significant decrease of sorption capacity after the first cycle was observed for FO36 resin. © 2017 Society of Chemical IndustryPreprin

RNA-binding properties and membrane insertion of Melon necrotic spot virus (MNSV) double gene block movement proteins

Advances in structural and biochemical properties of carmovirus movement proteins (MPs) have only been obtained in p7 and p9 from Carnation mottle virus (CarMV). Alignment of carmovirus MPs revealed a low conservation of amino acid identity but interestingly, similarity was elevated in regions associated with the functional secondary structure elements reported for CarMV which were conserved in all studied proteins. Nevertheless, some differential features in relation with CarMV MPs were identified in those from Melon necrotic virus (MNSV) (p7A and p7B). p7A was a soluble non-sequence specific RNA-binding protein, but unlike CarMV p7, its central region alone could not account for the RNA-binding properties of the entire protein. In fact, a 22-amino acid synthetic peptide whose sequence corresponds to this central region rendered an apparent dissociation constant (K(d)) significantly higher than that of the corresponding entire protein (9 mM vs. 0.83-25.7 microM). This p7A-derived peptide could be induced to fold into an alpha-helical structure as demonstrated for other carmovirus p7-like proteins. Additionally, in vitro fractionation of p7B transcription/translation mixtures in the presence of ER-derived microsomal membranes strongly suggested that p7B is an integral membrane protein. Both characteristics of these two small MPs forming the double gene block (DGB) of MNSV are discussed in the context of the intra- and intercellular movement of carmovirus