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Sample records for yellow mottle virus

  1. potential for biological control of rice yellow mottle virus vectors

    African Journals Online (AJOL)

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    Insect pests and disease infestations are the primary constraints in rice (Oryza sativa) production .... Asia. Of all the rice diseases, the one caused by the rice yellow mottle virus (RYMV), first reported ..... yellow mottle virus in Central Africa.

  2. Prevalence of Rice Yellow Mottle Virus (RYMV) on Rice Plants ...

    African Journals Online (AJOL)

    Abstract. Incidence of Rice yellow mottle virus (RYMV) on rice plants (ofada) grown in two local government areas (LGAs) of Ogun State had been evaluated during a two year field survey. Six month old rice plants were observed for symptom expression and leaf samples collected for serological indexing. Of the 60 leaf ...

  3. Rice yellow mottle virus is transmitted by cows, donkeys, and grass rats in irrigated rice crops

    NARCIS (Netherlands)

    Sarra, S.; Peters, D.

    2003-01-01

    Rice yellow mottle virus (RYMV), endemic in Africa, is believed to be spread by chrysomelid beetles, although the infections in a field often cannot be explained by the prevailing number of beetles. We show that the grass rat Arvicanthis niloticus, domestic cows (Bos spp.), and donkeys (Asinus spp.)

  4. Evidence for Non-Transmission of Rice Yellow Mottle Virus (RYMV through Rice Seed

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    Sy, AA.

    2004-01-01

    Full Text Available An indexing of the organs (radicle and plumule and components (husk, endosperm and embryo of rice seeds using Enzyme Linked Immunosorbent Assay (ELISA was carried out to detect Rice yellow mottle virus (RYMV and establish the exact location of the virus in the rice seed. RYMV was detected only in the husk (seed coat but not in the endosperm, plumule, radicle, nor embryo. None of the seedlings raised from the seeds expressed RYMV symptoms. No virus particle was detected by the ELISA test in the leaves of the screenhouse-reared plants obtained from seeds of infected plants. The results indicate that RYMV is apparently not transmitted through rice seed probably because the virus is seed-borne in the husk (seed coat of mature rice seeds.

  5. Cooking and Eating Quality of Rice Yellow Mottle Virus Resistant ...

    African Journals Online (AJOL)

    Cooking and Eating Quantity of Rice Yellow Mottle 195 varieties often out compete introduced varieties on local markets; even though the former have lower yield potential. Breeding work incorporating grain quality was started in 1972 with the aim of developing varieties which combine high grain yield and grain quality ...

  6. Occurrence of Squash yellow mild mottle virus and Pepper golden mosaic virus in Potential New Hosts in Costa Rica.

    Science.gov (United States)

    Castro, Ruth M; Moreira, Lisela; Rojas, María R; Gilbertson, Robert L; Hernández, Eduardo; Mora, Floribeth; Ramírez, Pilar

    2013-09-01

    Leaf samples of Solanum lycopersicum, Capsicum annuum, Cucurbita moschata, Cucurbita pepo, Sechium edule and Erythrina spp. were collected. All samples were positive for begomoviruses using polymerase chain reaction and degenerate primers. A sequence of ∼1,100 bp was obtained from the genomic component DNA-A of 14 samples. In addition, one sequence of ∼580 bp corresponding to the coat protein (AV1) was obtained from a chayote (S. edule) leaf sample. The presence of Squash yellow mild mottle virus (SYMMoV) and Pepper golden mosaic virus (PepGMV) were confirmed. The host range reported for SYMMoV includes species of the Cucurbitaceae, Caricaceae and Fabaceae families. This report extends the host range of SYMMoV to include the Solanaceae family, and extends the host range of PepGMV to include C. moschata, C. pepo and the Fabaceae Erythrina spp. This is the first report of a begomovirus (PepGMV) infecting chayote in the Western Hemisphere.

  7. Occurrence of Squash yellow mild mottle virus and Pepper golden mosaic virus in Potential New Hosts in Costa Rica

    Directory of Open Access Journals (Sweden)

    Ruth M. Castro

    2013-09-01

    Full Text Available Leaf samples of Solanum lycopersicum, Capsicum annuum, Cucurbita moschata, Cucurbita pepo, Sechium edule and Erythrina spp. were collected. All samples were positive for begomoviruses using polymerase chain reaction and degenerate primers. A sequence of ∼1,100 bp was obtained from the genomic component DNA-A of 14 samples. In addition, one sequence of ∼580 bp corresponding to the coat protein (AV1 was obtained from a chayote (S. edule leaf sample. The presence of Squash yellow mild mottle virus (SYMMoV and Pepper golden mosaic virus (PepGMV were confirmed. The host range reported for SYMMoV includes species of the Cucurbitaceae, Caricaceae and Fabaceae families. This report extends the host range of SYMMoV to include the Solanaceae family, and extends the host range of PepGMV to include C. moschata, C. pepo and the Fabaceae Erythrina spp. This is the first report of a begomovirus (PepGMV infecting chayote in the Western Hemisphere.

  8. Rapid detection of Piper yellow mottle virus and Cucumber mosaic virus infecting black pepper (Piper nigrum) by loop-mediated isothermal amplification (LAMP).

    Science.gov (United States)

    Bhat, A I; Siljo, A; Deeshma, K P

    2013-10-01

    The loop-mediated isothermal amplification (LAMP) assay for Piper yellow mottle virus and the reverse transcription (RT) LAMP assay for Cucumber mosaic virus each consisted of a set of five primers designed against the conserved sequences in the viral genome. Both RNA and DNA isolated from black pepper were used as a template for the assay. The results were assessed visually by checking turbidity, green fluorescence and pellet formation in the reaction tube and also by gel electrophoresis. The assay successfully detected both viruses in infected plants whereas no cross-reactions were recorded with healthy plants. Optimum conditions for successful amplification were determined in terms of the concentrations of magnesium sulphate and betaine, temperature, and duration. The detection limit for both LAMP and RT-LAMP was up to 100 times that for conventional PCR and up to one-hundredth of that for real-time PCR. The optimal conditions arrived at were validated by testing field samples of infected vines of three species from different regions. Copyright © 2013 Elsevier B.V. All rights reserved.

  9. Rice Yellow Mottle Virus stress responsive genes from susceptible and tolerant rice genotypes

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    Siré Christelle

    2008-03-01

    Full Text Available Abstract Background The effects of viral infection involve concomitant plant gene variations and cellular changes. A simple system is required to assess the complexity of host responses to viral infection. The genome of the Rice yellow mottle virus (RYMV is a single-stranded RNA with a simple organisation. It is the most well-known monocotyledon virus model. Several studies on its biology, structure and phylogeography have provided a suitable background for further genetic studies. 12 rice chromosome sequences are now available and provide strong support for genomic studies, particularly physical mapping and gene identification. Results The present data, obtained through the cDNA-AFLP technique, demonstrate differential responses to RYMV of two different rice cultivars, i.e. susceptible IR64 (Oryza sativa indica, and partially resistant Azucena (O. s. japonica. This RNA profiling provides a new original dataset that will enable us to gain greater insight into the RYMV/rice interaction and the specificity of the host response. Using the SIM4 subroutine, we took the intron/exon structure of the gene into account and mapped 281 RYMV stress responsive (RSR transcripts on 12 rice chromosomes corresponding to 234 RSR genes. We also mapped previously identified deregulated proteins and genes involved in partial resistance and thus constructed the first global physical map of the RYMV/rice interaction. RSR transcripts on rice chromosomes 4 and 10 were found to be not randomly distributed. Seven genes were identified in the susceptible and partially resistant cultivars, and transcripts were colocalized for these seven genes in both cultivars. During virus infection, many concomitant plant gene expression changes may be associated with host changes caused by the infection process, general stress or defence responses. We noted that some genes (e.g. ABC transporters were regulated throughout the kinetics of infection and differentiated susceptible and

  10. Characterization of sida golden mottle virus isolated from Sida santaremensis Monteiro in Florida.

    Science.gov (United States)

    Al-Aqeel, H A; Iqbal, Zafar; Polston, J E

    2018-06-21

    The genome of sida golden mottle virus (SiGMoV) (GU997691 and GU997692) isolated from Sida santaremensis Monteiro in Manatee County, Florida, was sequenced and characterized. SiGMoV was determined to be a bipartite virus belonging to the genus Begomovirus with a genome organization typical of the New World viruses in the genus. SiGMoV DNA-A had the highest identity scores (89%) and showed the closest evolutionary relationships to sida golden mosaic Buckup virus (SiGMBuV) (JX162591 and HQ008338). However, SiGMoV DNA-B had the highest identity scores (93%) and showed the closest evolutionary relationship to corchorus yellow spot virus (DQ875869), SiGMBuV (JX162592) and sida golden mosaic Florida virus (SiGMFlV) (HE806443). There was extensive recombination in the SiGMoV DNA-A and much less in DNA-B. Full-length clones of SiGMoV were infectious and were able to infect and cause symptoms in several plant species.

  11. Characterization of cowpea chlorotic mottle virus and its assembly

    NARCIS (Netherlands)

    Verduin, B.J.M.

    1978-01-01

    This thesis decribes the conditions for isolation of cowpea chlorotic mottle virus (CCMV), its ribonucleic acid (RNA) and the coat protein, the characterization of the virus and its constituents (chapter 3, 4 and 5) and the dissociation and assembly behaviour of the virus (chapter 6 and

  12. Survey of Cherry necrotic rusty mottle virus and Cherry green ring mottle virus incidence in Korea by Duplex RT-PCR

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    Seung-Yeol Lee

    2014-12-01

    Full Text Available The incidence of Cherry necrotic rusty mottle virus (CNRMV and Cherry green ring mottle virus (CGRMV have recently been occurred in Korea, posing a problem for sweet cherry cultivation. Since infected trees have symptomless leaves or ring-like spots on the pericarp, it is difficult to identify a viral infection. In this study, the incidence of CNRMV and CGRMV in sweet cherry in Gyeongbuk province was surveyed using a newly developed duplex reverse transcriptase polymerase chain reaction (RT-PCR method that can detect both viruses in a single reaction. CNRMV and CGRMV co-infection rates were 29.6%, 53.6%, and 17.6%, respectively, in samples collected from three different sites (Daegu, Gyeongju and Gyeongsan in Gyeongbuk province during 2012 and 2013. This duplex RT-PCR method offers a simple, rapid, and effective way of identifying CNRMV and CGRMV simultaneously in sweet cherry trees, which can aid in the management of viral infections that could undermine yield.

  13. Spectroscopy on the assembly of cowpea chlorotic mottle virus

    NARCIS (Netherlands)

    Kruese, J.

    1979-01-01

    This thesis describes the characterization of cowpea chlorotic mottle virus (CCMV) by using spectroscopic techniques. In chapter one and two the main properties of CCMV, which belongs to the bromoviruses, are summarized. The application of spectroscopic techniques in the study of other viruses is

  14. Identification of Cherry green ring mottle virus on Sweet Cherry Trees in Korea

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    In-Sook Cho

    2013-12-01

    Full Text Available During the 2012 growing season, 154 leaf samples were collected from sweet cherry trees in Hwaseong, Pyeongtaek, Gyeongju, Kimcheon, Daegu, Yeongju and Eumseong and tested for the presence of Cherry green ring mottle virus (CGRMV. PCR products of the expected size (807 bp were obtained from 6 samples. The PCR products were cloned and sequenced. The nucleotide sequences of the clones showed over 88% identities to published coat protein sequences of CGRMV isolates in the GenBank database. The sequences of CGRMV isolates, CGR-KO 1−6 shared 98.8 to 99.8% nucleotide and 99.6 to 100% amino acid similarities. Phylogenetic analysis indicated that the Korean CGRMV isolates belong to the group II of CGRMV coat protein genes. The CGRMV infected sweet cherry trees were also tested for Apple chlorotic leaf spot virus (ACLSV, Apple mosaic virus (ApMV, Cherry necrotic rusty mottle virus (CNRMV, Cherry mottle leaf virus (CMLV, Cherry rasp leaf virus (CRLV, Cherry leafroll virus (CLRV, Cherry virus A (CVA, Little cherry virus 1 (LChV1, Prune dwarf virus (PDV and Prunus necrotic ringspot virus (PNRSV by RT-PCR. All of the tested trees were also infected with ACLSV.

  15. First Report of Carnation vein mottle virus Infecting Dianthus amurensis in China

    Science.gov (United States)

    Tomato mottle mosaic virus (ToMMV), a tentative member in genus Tobamovirus, was first reported from a greenhouse tomato sample collected in Mexico in 2013 (1). In August 2013, foliar mottle, shrinking and necrosis were observed on pepper plants in several vegetable greenhouses of Lhasa, Tibet Auton...

  16. Occurrence of pepper mild mottle virus in greenhouse- grown ...

    African Journals Online (AJOL)

    Administrator

    2011-06-08

    Jun 8, 2011 ... Pepper mild mottle virus (PMMoV) is one of the most ... Figure 1. Map of the West Mediterranean region of Turkey showing areas in which the surveys were conducted. showing virus-like symptoms were taken from symptomatic pepper .... SM, Maniloff J, Mayo MA, McGeoch D, Pringle CR, Wickner RB (eds).

  17. A note on outbreak of cowpea mild mottle virus (CPMMV) in common bean in the River Nile State, Sudan

    International Nuclear Information System (INIS)

    Hamed, A. A.; Elkhair, J.; Elfaha, A.

    2010-01-01

    An outbreak of a devastating virus disease occurred in common ben (phaseolus vulgaris) in Berber area, the River Nile State, during the 2004/2005 cropping season, with symptoms of stunting and yellowing. The disease incidence reached a level of more than 85% in all visited fields. One hundred fifty symptomatic samples, collected from different fields at Hudeiba, Berber and Shendi were blotted on nitrocellulose membranes and tested for the presence of different viruses, using the tissue blot immunoassay (TBIA) technique. The results of the serological tests revealed that 95% of the samples were positive for cowpea mild mottle virus (CPMMV). Among the common bean genotypes screened for resistance to CPMMV, only RO/2/1 and Giza 3 were resistant to the disease.(Author)

  18. Virus surveys of Capsicum spp. in the Republic of Benin reveal the prevalence of pepper vein yellows virus and the identification of a previously uncharacterised polerovirus species.

    Science.gov (United States)

    Afouda, Leonard; Kone, Daouda; Zinsou, Valerien; Dossou, Laurence; Kenyon, Lawrence; Winter, Stephan; Knierim, Dennis

    2017-06-01

    Surveys were conducted in 2014 and 2015 in Southern and Northern Benin, respectively, to identify the viruses infecting peppers (Capsicum spp.). The samples were screened by ELISA for cucumber mosaic virus (CMV), pepper veinal mottle virus (PVMV), potato virus Y (PVY) and tomato yellow leaf curl virus (TYLCV). A generic reverse transcription PCR (RT-PCR) was used to test for the presence of poleroviruses. ELISA tests confirmed the prevalence of all viruses, while the RT-PCR detected pepper vein yellows virus (PeVYV) which is reported for the first time in Benin. A further, divergent polerovirus isolate was detected from a single pepper sample originating from southern Benin. Screening of samples collected from solanaceous plants during virus surveys in Mali (conducted in 2009) also detected this divergent polerovirus isolate in two samples from African eggplants. The complete genome sequence was obtained from the Mali isolate using transcriptome sequencing and by conventional Sanger sequencing of overlapping RT-PCR products. Based on the sequence characteristics of this isolate we propose a new polerovirus species, African eggplant yellowing virus (AeYV).

  19. Structure of Cowpea mottle virus: a consensus in the genus Carmovirus

    International Nuclear Information System (INIS)

    Ke Jiyuan; Schmidt, Timothy; Chase, Elaine; Bozarth, Robert F.; Smith, Thomas J.

    2004-01-01

    Cowpea mottle virus (CPMoV) is a T = 3 virus that belongs to Carmovirus genus of the Tombusviridae family. Here, we report the crystal structure of CPMoV determined to a resolution of 7.0 A. The structures and sequences of three Carmoviruses, CPMoV, Turnip crinkle virus (TCV), and Carnation mottle virus (CarMV) have been compared to TBSV from the Tombusvirus genus. CPMoV, TCV, and CarMV all have a deletion in βC strand in the S domain relative to TBSV that may be distinctive to the genus. Although CPMoV has an elongated C-terminus like TBSV, it does not interact with the icosahedrally related P domain as observed in TBSV. In CPMoV, the termini of A and B interact with the icosahedrally related shell domains of A and C, respectively, to form a chain of interactions around the 5-fold axes. The C subunit terminus does not, however, interact with the B subunit because of quasi-equivalent differences in the P domain orientations

  20. Detection and distribution of sweetpotato feathery mottle virus in ...

    African Journals Online (AJOL)

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    the evolution as well as the distribution of the feathery mottle virus was followed. Thus, the individuals tested have a high viral ... insured by bees. However, under natural conditions, few flowers are observed as well as incompatibility phenomena that are responsible for a weak seeds production. This plant is grown annually ...

  1. Bean Pod Mottle Virus (BPMV) (Genus Comovirus ): A Limiting ...

    African Journals Online (AJOL)

    The reactions of twenty soybean varieties to infection with Bean Pod Mottle Virus (BPMV) (Genus Comovirus) disease were studied for 2 consecutive years in the Department of Crop Science University of Nigeria, Nsukka Farm (Latitude 060 25N; Longitude 070 24N; attitude 447.26 m above sea level). Factorial arrangement ...

  2. Feasibility of Cowpea chlorotic mottle virus-like particles as scaffold for epitope presentations

    NARCIS (Netherlands)

    Hassani-Mehraban, A.; Creutzburg, S.; Heereveld, van L.; Kormelink, R.J.M.

    2015-01-01

    Within the last decade Virus-Like Particles (VLPs) have increasingly received attention from scientists for their use as a carrier of (peptide) molecules or as scaffold to present epitopes for use in subunit vaccines. To test the feasibility of Cowpea chlorotic mottle virus (CCMV) particles as a

  3. Molecular interactions during the assembly of cowpea chlorotic mottle virus studied by magnetic resonance

    NARCIS (Netherlands)

    Vriend, G.

    1983-01-01

    This thesis describes the application of 1 H- and 13 C- NMR, EPR, ST-EPR and calculational methods to study cowpea chlorotic mottle virus. This virus consists of RNA encapsidated by 180 identical protein subunits, arranged icosahedrally. The

  4. Virus incidence in orchardgrass (Dactylis glomerata L.) seed production fields in the Willamette Valley

    Science.gov (United States)

    A survey was conducted over the course of three years (2014-2016) for the presence of Barley yellow dwarf virus (BYDV-MAV and BYDV-PAV), Cereal yellow dwarf virus (CYDV-RPV), and Cocksfoot mottle virus (CfMV) in orchardgrass (Dactylis glomerata) fields in the Willamette Valley, Oregon. There was an ...

  5. Highly Specific Detection of Five Exotic Quarantine Plant Viruses using RT-PCR

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    Hoseong Choi

    2013-03-01

    Full Text Available To detect five plant viruses (Beet black scorch virus, Beet necrotic yellow vein virus, Eggplant mottled dwarf virus, Pelargonium zonate spot virus, and Rice yellow mottle virus for quarantine purposes, we designed 15 RT-PCR primer sets. Primer design was based on the nucleotide sequence of the coat protein gene, which is highly conserved within species. All but one primer set successfully amplified the targets, and gradient PCRs indicated that the optimal temperature for the 14 useful primer sets was 51.9°C. Some primer sets worked well regardless of annealing temperature while others required a very specific annealing temperature. A primer specificity test using plant total RNAs and cDNAs of other plant virus-infected samples demonstrated that the designed primer sets were highly specific and generated reproducible results. The newly developed RT-PCR primer sets would be useful for quarantine inspections aimed at preventing the entry of exotic plant viruses into Korea.

  6. Short communication. First report of Eggplant mottled dwarf virus in China rose in southern Spain

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    G. Parrella

    2013-01-01

    Full Text Available Eggplant mottled dwarf virus (EMDV, genus Nucleorhabdovirus, family Rhabdoviridae is transmitted in nature by leafhoppers and its natural host range includes vegetable crops (eggplant, tomato, potato, pepper, ornamentals (pittosporum, honeysuckle, pelargonium and wild plants (caper, Solanum nigrum. The prevalence of infections is generally very low. EMDV has been demonstrated to be the causal agent of a vein yellowing disease of China rose (Hibiscus rosa-sinensis in southern Italy. In this work, four locations from Málaga and Granada provinces (southern Spain were surveyed in 2011 to study the prevalence of EMDV infections in China rose by serological and molecular methods. Overall, EMDV was detected in 77.3% of the samples (33 out of 45 samples tested. Mechanical transmission tests and immunoelectron microscopy confirmed the presence of EMDV. The possible causes of such a high and unexpected prevalence are discussed. The use of molecular hibridization with an EMDV specific riboprobe is proposed for early screening of vegetative propagated China rose plants to avoid dissemination of infected material.

  7. Complete genome sequence of a tomato infecting tomato mottle mosaic virus in New York

    Science.gov (United States)

    Complete genome sequence of an emerging isolate of tomato mottle mosaic virus (ToMMV) infecting experimental nicotianan benthamiana plants in up-state New York was obtained using small RNA deep sequencing. ToMMV_NY-13 shared 99% sequence identity to ToMMV isolates from Mexico and Florida. Broader d...

  8. Inheritance and molecular mapping of an allele providing resistance to Cowpea mild mottle virus-like symptoms in soybean

    Science.gov (United States)

    Damage to soybean [Glycine max (L.) Merr.] from Cowpea mild mottle virus-like (CPMMV-L) symptoms (family: Betaflexiviridae, genus: Carlavirus) has been of increasing concern in Argentina, Brazil, Mexico, and Puerto Rico. Soybean cultivars and lines differing in their reaction to the virus have been ...

  9. Versatile post-functionalization of the external shell of cowpea chlorotic mottle virus by using click chemistry

    NARCIS (Netherlands)

    Hommersom, C.A.; Matt, B.D.; van der Ham, A.M.; Cornelissen, Jeroen Johannes Lambertus Maria; Katsonis, Nathalie Hélène

    2014-01-01

    We present the modification of the outer protein shell of cowpea chlorotic mottle virus (CCMV) with linear and strained alkyne groups. These functionalized protein capsids constitute valuable platforms for post-functionalization via click chemistry. After modification, the integrity of the capsid

  10. The complete nucleotide sequence of the Barley yellow dwarf virus-RMV genome reveals it to be a new Polerovirus distantly related to other yellow dwarf viruses

    Science.gov (United States)

    The yellow dwarf viruses (YDVs) of the Luteoviridae family represent the most widespread group of cereal viruses worldwide. They include the Barley yellow dwarf viruses (BYDVs) of genus Luteovirus, the Cereal yellow dwarf viruses (CYDVs) and Wheat yellow dwarf virus (WYDV) of genus Polerovirus. All ...

  11. Detection of sweet potato virus C, sweet potato virus 2 and sweet potato feathery mottle virus in Portugal.

    Science.gov (United States)

    Varanda, Carla M R; Santos, Susana J; Oliveira, Mônica D M; Clara, Maria Ivone E; Félix, Maria Rosário F

    2015-06-01

    Field sweet potato plants showing virus-like symptoms, as stunting, leaf distortion, mosaic and chlorosis, were collected in southwest Portugal and tested for the presence of four potyviruses, sweet potato virus C (SPVC), sweet potato virus 2 (SPV2), sweet potato feathery mottle virus (SPFMV), sweet potato virus G (SPVG), and the crinivirus sweet potato chlorotic stunt virus (SPCSV). DsRNA fractions were extracted from symptomatic leaves and used as templates in single and multiplex RT-PCR assays using previously described specific primers for each analyzed virus. The amplified reaction products for SPVC, SPV2 and SPFMV were of expected size, and direct sequencing of PCR products revealed that they correspond to the coat protein gene (CP) and showed 98%, 99% and 99% identity, respectively, to those viruses. Comparison of the CP genomic and amino acid sequences of the Portuguese viral isolates recovered here with those of ten other sequences of isolates obtained in different countries retrieved from the GenBank showed very few differences. The application of the RT-PCR assays revealed for the first time the presence of SPVC and SPFMV in the sweet potato crop in Portugal, the absence of SPVG and SPCSV in tested plants, as well as the occurrence of triple virus infections under field conditions.

  12. Biological and molecular characterization of a putative new sobemovirus infecting Imperata cylindrica and maize in Africa.

    Science.gov (United States)

    Sérémé, Drissa; Lacombe, Séverine; Konaté, Moumouni; Pinel-Galzi, Agnès; Traoré, Valentin Stanislas Edgar; Hébrard, Eugénie; Traoré, Oumar; Brugidou, Christophe; Fargette, Denis; Konaté, Gnissa

    2008-01-01

    A new virus was isolated from both the grass Imperata cylindrica and maize plants that had yellow mottle symptoms in Burkina Faso, West Africa. The virus has isometric particles ca. 32 nm in diameter. The experimental host range was restricted to Rottboellia exaltata. Virions were isolated from leaves of systemically infected maize plants. Koch's postulates were completed by mechanically inoculating uninfected Imperata or maize with either purified virus or sap from infected Imperata plants. Virion preparations were used to produce a specific polyclonal antiserum, and an enzyme-linked immunosorbent assay test was set up. The full genome of the virus was sequenced, and it comprised 4,547 nucleotides. Phylogenetic studies indicated that the virus is closely related to rice yellow mottle virus, a sobemovirus that infects monocotyledons in Africa, and is more distantly related to cocksfoot mottle virus, another sobemovirus that infects monocotyledons. Although the virus can infect R. exaltata experimentally, it differs from Rottboellia yellow mottle virus, a member of a tentative species of the genus Sobemovirus that also infects monocotyledons in Africa. Particle morphology, serological properties, genomic organization, and phylogenetic analysis are all consistent with assignment of the new virus to the genus Sobemovirus. The name Imperata yellow mottle virus is proposed.

  13. METODE PENAPISAN CABAI (CAPSICUM ANNUUM L. UNTUK KETAHANAN TERHADAP CHILLI VEINAL MOTTLE VIRUS (Chi VMV DAN CUCUMBER MOSAIC VIRUS (CMV

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    Latifah, Sri Hendrastuti Hidayat, dan Sriani Sujiprihati .

    2011-11-01

    Full Text Available Screening Method for Chilli Veinal Mottle Virus  (Chi VMV and Cucumber Mosaic Virus  (CMV Resistance in Chillipepper.  ChiVMV and CMV have been reported as the causal agents of main diseases in chillipepper in Indonesia and other Asian countries.  Mix infection of this two viruses was commonly occurred in the field, causing severe disease .  The use of resistance varieties has been proposed for dealing with the yield losses causing by  the viruses.  Breeding program is undergoing for development of chillipepper varieties resistant to ChiVMV and CMV.  Methodology for routine screening activity of chillipepper for resistance to both ChiVMV and CMV needs to be established. This research was conducted in Cikabayan Glass House and Plant Virology Laboratory, Plant Protection Department, Bogor Agricultural University from May 2006 to June 2007. Aim of the research was to develop screening method for simultaneous infection by the two viruses, ChiVMV and CMV.  Inoculation of ChiVMV and CMV was done by single inoculation or repetitive inoculation methods.  In both methods, ChiVMV and CMV were inoculated in different sequences, either ChiVMV or CMV first.  The result showed that incubation period was shorter when CMV was inoculated in advance both in single and repetitive inoculation method.  Mosaic, mottle and malformation type symptom was observed in infected plants. Based on disease incidence, infection of ChiVMV was higher compared to CMV in repetitive inoculation as well as in single inoculation.  Repetitive inoculation methods with virus sequence ChiVMV-CMV-ChiVMV-CMV  was selected for resistance evaluation of chillipepper genotypes.

  14. Metal-ion-induced formation and stabilization of protein cages based on the cowpea chlorotic mottle virus

    NARCIS (Netherlands)

    Minten, Inge J.; Wilke, Koos D.M.; Hendriks, Linda J.A.; van Hest, Jan C.M.; Nolte, Roeland J.M.; Cornelissen, Jeroen Johannes Lambertus Maria

    2011-01-01

    The cowpea chlorotic mottle virus (CCMV) is a versatile building block for the construction of nanoreactors and functional materials. Upon RNA removal, the capsid can be reversibly assembled and disassembed by adjusting the pH. At pH 5.0 the capsid is in the native assembled conformation, while at

  15. Rapid detection of fifteen known soybean viruses by dot-immunobinding assay.

    Science.gov (United States)

    Ali, Akhtar

    2017-11-01

    A dot-immunobinding assay (DIBA) was optimized and used successfully for the rapid detection of 15 known viruses [Alfalfa mosaic virus (AMV), Bean pod mottle virus (BPMV), Bean yellow mosaic virus (BYMV), Cowpea mild mottle virus (CPMMV), Cowpea severe mosaic virus (CPSMV), Cucumber mosaic virus (CMV), Peanut mottle virus (PeMoV), Peanut stunt virus (PSV), Southern bean mosaic virus (SBMV), Soybean dwarf virus (SbDV), Soybean mosaic virus (SMV), Soybean vein necrosis virus (SVNV), Tobacco ringspot virus (TRSV), Tomato ringspot virus (ToRSV), and Tobacco streak virus (TSV)] infecting soybean plants in Oklahoma. More than 1000 leaf samples were collected in approximately 100 commercial soybean fields in 24 counties of Oklahoma, during the 2012-2013 growing seasons. All samples were tested by DIBA using polyclonal antibodies of the above 15 plant viruses. Thirteen viruses were detected, and 8 of them were reported for the first time in soybean crops of Oklahoma. The highest average incidence was recorded for PeMoV (13.5%) followed by SVNV (6.9%), TSV (6.4%), BYMV, (4.5%), and TRSV (3.9%), while the remaining seven viruses were detected in less than 2% of the samples tested. The DIBA was quick, and economical to screen more than 1000 samples against 15 known plant viruses in a very short time. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. Transcriptome analysis of watermelon (Citrullus lanatus) fruits in response to Cucumber green mottle mosaic virus (CGMMV) infection

    OpenAIRE

    Li, Xiaodong; An, Mengnan; Xia, Zihao; Bai, Xiaojiao; Wu, Yuanhua

    2017-01-01

    Cucumber green mottle mosaic virus (CGMMV) belongs to the Tobamovirus genus and is a major global plant virus on cucurbit plants. It causes severe disease symptoms on infected watermelon plants (Citrullus lanatus), particularly inducing fruit decay. However, little is known about the molecular mechanism of CGMMV-induced watermelon fruit decay. For this study, comparative analysis of transcriptome profiles of CGMMV-inoculated and mock-inoculated watermelon fruits were conducted via RNA-Seq. A ...

  17. Complete genome analysis of a novel umbravirus-polerovirus combination isolated from Ixeridium dentatum.

    Science.gov (United States)

    Yoo, Ran Hee; Lee, Seung-Won; Lim, Seungmo; Zhao, Fumei; Igori, Davaajargal; Baek, Dasom; Hong, Jin-Sung; Lee, Su-Heon; Moon, Jae Sun

    2017-12-01

    Two novel viruses, isolated in Bonghwa, Republic of Korea, from an Ixeridium dentatum plant with yellowing mottle symptoms, have been provisionally named Ixeridium yellow mottle-associated virus 1 (IxYMaV-1) and Ixeridium yellow mottle-associated virus 2 (IxYMaV-2). IxYMaV-1 has a genome of 6,017 nucleotides sharing a 56.4% sequence identity with that of cucurbit aphid-borne yellows virus (genus Polerovirus). The IxYMaV-2 genome of 4,196 nucleotides has a sequence identity of less than 48.3% with e other species classified within the genus Umbravirus. Genome properties and phylogenetic analysis suggested that IxYMaV-1 and -2 are representative isolates of new species classifiable within the genus Polerovirus and Umbravirus, respectively.

  18. Identification of Common Epitopes on a Conserved Region of NSs Proteins Among Tospoviruses of Watermelon silver mottle virus Serogroup.

    Science.gov (United States)

    Chen, Tsung-Chi; Huang, Ching-Wen; Kuo, Yan-Wen; Liu, Fang-Lin; Yuan, Chao-Hsiu Hsuan; Hsu, Hei-Ti; Yeh, Shyi-Dong

    2006-12-01

    ABSTRACT The NSs protein of Watermelon silver mottle virus (WSMoV) was expressed by a Zucchini yellow mosaic virus (ZYMV) vector in squash. The expressed NSs protein with a histidine tag and an additional NIa protease cleavage sequence was isolated by Ni(2+)-NTA resins as a free-form protein and further eluted after sodium dodecyl sulfate-polyacrylamide gel electrophoresis for production of rabbit antiserum and mouse monoclonal antibodies (MAbs). The rabbit antiserum strongly reacted with the NSs crude antigen of WSMoV and weakly reacted with that of a high-temperature-recovered gloxinia isolate (HT-1) of Capsicum chlorosis virus (CaCV), but not with that of Calla lily chlorotic spot virus (CCSV). In contrast, the MAbs reacted strongly with all crude NSs antigens of WSMoV, CaCV, and CCSV. Various deletions of the NSs open reading frame were constructed and expressed by ZYMV vector. Results indicate that all three MAbs target the 89- to 125-amino-acid (aa) region of WSMoV NSs protein. Two indispensable residues of cysteine and lysine were essential for MAbs recognition. Sequence comparison of the deduced MAbs-recognized region with the reported tospoviral NSs proteins revealed the presence of a consensus sequence VRKPGVKNTGCKFTMHNQIFNPN (denoted WNSscon), at the 98- to 120-aa position of NSs proteins, sharing 86 to 100% identities among those of WSMoV, CaCV, CCSV, and Peanut bud necrosis virus. A synthetic WNSscon peptide reacted with the MAbs and verified that the epitopes are present in the 98- to 120-aa region of WSMoV NSs protein. The WSMoV sero-group-specific NSs MAbs provide a means for reliable identification of tospoviruses in this large serogroup.

  19. Detection of cucumber green mottle mosaic virus-infected watermelon seeds using short wave infrared (SWIR) hyperspectral imaging system

    Science.gov (United States)

    The cucurbit diseases caused by cucumber green mottle mosaic virus (CGMMV) have led to a serious problem to growers and seed producers because it is difficult to prevent spreading through causal agent of seeds. Conventional detection methods for infected seed such as a biological, serological, and m...

  20. Classification of cucumber green mottle mosaic virus (CGMMV) infected watermelon seeds using Raman spectroscopy

    Science.gov (United States)

    Lee, Hoonsoo; Lim, Hyoun-Sub; Cho, Byoung-Kwan

    2016-05-01

    The Cucumber Green Mottle Mosaic Virus (CGMMV) is a globally distributed plant virus. CGMMV-infected plants exhibit severe mosaic symptoms, discoloration, and deformation. Therefore, rapid and early detection of CGMMV infected seeds is very important for preventing disease damage and yield losses. Raman spectroscopy was investigated in this study as a potential tool for rapid, accurate, and nondestructive detection of infected seeds. Raman spectra of healthy and infected seeds were acquired in the 400 cm-1 to 1800 cm-1 wavenumber range and an algorithm based on partial least-squares discriminant analysis was developed to classify infected and healthy seeds. The classification model's accuracies for calibration and prediction data sets were 100% and 86%, respectively. Results showed that the Raman spectroscopic technique has good potential for nondestructive detection of virus-infected seeds.

  1. Barley yellow dwarf virus: Luteoviridae or Tombusviridae?

    Science.gov (United States)

    Miller, W Allen; Liu, Sijun; Beckett, Randy

    2002-07-01

    Summary Barley yellow dwarf virus (BYDV), the most economically important virus of small grains, features highly specialised relationships with its aphid vectors, a plethora of novel translation mechanisms mediated by long-distance RNA interactions, and an ambiguous taxonomic status. The structural and movement proteins of BYDV that confer aphid transmission and phloem-limitation properties resemble those of the Luteoviridae, the family in which BYDV is classified. In contrast, many genes and cis-acting signals involved in replication and gene expression most closely resemble those of the Tombusviridae. BYDV is in genus Luteovirus, family Luteoviridae. BYDV includes at least two serotypes or viruses: BYDV-PAV and BYDV-MAV. The former BYDV-RPV is now Cereal yellow dwarf virus-RPV (CYDV-RPV). CYDV is in genus Polerovirus, family Luteoviridae. Genus Luteovirus shares many features with family Tombusviridae. Physical properties: approximately 25 nm icosahedral (T = 3) virions. One major (22 kDa) and one minor (50-55 kDa) coat protein. 5.6-5.8 kb positive sense RNA genome with no 5'-cap and no poly(A) tail. Most grasses. Most important in oats, barley and wheat. Also infects maize and rice. Yellowing and dwarfing in barley, stunting in wheat; reddening, yellowing and blasting in oats. Some isolates cause leaf notching and curling. Key attractions: Model for the study of circulative transmission of aphid-transmitted viruses. Plethora of unusual translation mechanisms. Evidence of recombination in recent evolutionary history creates taxonomic ambiguity. Economically important virus of wheat, barley and oats, worldwide. Useful websites/meetings: International symposium: 'Barley Yellow Dwarf Disease: Recent Advances and Future Strategies', CIMMYT, El Batan, Mexico, 1-5 September 2002, http://www.cimmyt.cgiar.org/Research/wheat/Conf_BYD_02/invitation.htm http://www.cimmyt.org/Research/wheat/BYDVNEWS/htm/BYDVNEWS.htm Aphid transmission animation: http://www.ppws.vt.edu/~sforza/tmv/bydv_aph.html.

  2. Structural transitions in Cowpea chlorotic mottle virus (CCMV)

    Science.gov (United States)

    Liepold, Lars O.; Revis, Jennifer; Allen, Mark; Oltrogge, Luke; Young, Mark; Douglas, Trevor

    2005-12-01

    Viral capsids act as molecular containers for the encapsulation of genomic nucleic acid. These protein cages can also be used as constrained reaction vessels for packaging and entrapment of synthetic cargos. The icosahedral Cowpea chlorotic mottle virus (CCMV) is an excellent model for understanding the encapsulation and packaging of both genomic and synthetic materials. High-resolution structural information of the CCMV capsid has been invaluable for evaluating structure-function relationships in the assembled capsid but does not allow insight into the capsid dynamics. The dynamic nature of the CCMV capsid might play an important role in the biological function of the virus. The CCMV capsid undergoes a pH and metal ion dependent reversible structural transition where 60 separate pores in the capsid open or close, exposing the interior of the protein cage to the bulk medium. In addition, the highly basic N-terminal domain of the capsid, which is disordered in the crystal structure, plays a significant role in packaging the viral cargo. Interestingly, in limited proteolysis and mass spectrometry experiments the N-terminal domain is the first part of the subunit to be cleaved, confirming its dynamic nature. Based on our fundamental understanding of the capsid dynamics in CCMV, we have utilized these aspects to direct packaging of a range of synthetic materials including drugs and inorganic nanoparticles.

  3. Infeksi Cucumber mosaic virus dan Chilli veinal mottle virus pada Cabai di Kabupaten Rejang Lebong, Bengkulu

    Directory of Open Access Journals (Sweden)

    Mimi Sutrawati

    2013-04-01

    Full Text Available Mosaic disease caused by Cucumber mosaic virus (CMV and Chilli veinal mottle Virus (ChiVMV has been distributed widely in chilli in Indonesia and considered as important disease. A research was conducted to investigate the spread and incidence of CMV and ChiVMV in Rejang Lebong, Bengkulu and to identify its insect vector. Symptomatic and asymptomatic leaf samples were collected systematically from several chillipepper fields for further detection by DAS-ELISA (Double antibody sandwich-enzyme linked immunosorbant assay using specific antibody for CMV and ChiVMV. The result showed that infection of both CMV and ChiVMV was found with disease incidence reached 20-50%, whereas infection only by ChiVMV or CMV were 50-80% and 20-50%, respectively. One species of aphid, i.e. Aphis gossypii was found from the fields.Key words: Aphis gossypii, CMV, ChiVMV, disease incidence

  4. Two Novel Motifs of Watermelon Silver Mottle Virus NSs Protein Are Responsible for RNA Silencing Suppression and Pathogenicity.

    Science.gov (United States)

    Huang, Chung-Hao; Hsiao, Weng-Rong; Huang, Ching-Wen; Chen, Kuan-Chun; Lin, Shih-Shun; Chen, Tsung-Chi; Raja, Joseph A J; Wu, Hui-Wen; Yeh, Shyi-Dong

    2015-01-01

    The NSs protein of Watermelon silver mottle virus (WSMoV) is the RNA silencing suppressor and pathogenicity determinant. In this study, serial deletion and point-mutation mutagenesis of conserved regions (CR) of NSs protein were performed, and the silencing suppression function was analyzed through agroinfiltration in Nicotiana benthamiana plants. We found two amino acid (aa) residues, H113 and Y398, are novel functional residues for RNA silencing suppression. Our further analyses demonstrated that H113 at the common epitope (CE) ((109)KFTMHNQ(117)), which is highly conserved in Asia type tospoviruses, and the benzene ring of Y398 at the C-terminal β-sheet motif ((397)IYFL(400)) affect NSs mRNA stability and protein stability, respectively, and are thus critical for NSs RNA silencing suppression. Additionally, protein expression of other six deleted (ΔCR1-ΔCR6) and five point-mutated (Y15A, Y27A, G180A, R181A and R212A) mutants were hampered and their silencing suppression ability was abolished. The accumulation of the mutant mRNAs and proteins, except Y398A, could be rescued or enhanced by co-infiltration with potyviral suppressor HC-Pro. When assayed with the attenuated Zucchini yellow mosaic virus vector in squash plants, the recombinants carrying individual seven point-mutated NSs proteins displayed symptoms much milder than the recombinant carrying the wild type NSs protein, suggesting that these aa residues also affect viral pathogenicity by suppressing the host silencing mechanism.

  5. Ocorrência generalizada do Lettuce mottle virus em três regiões produtoras de alface comercial do Estado de São Paulo Occurrence of Lettuce mottle virus on three lettuce producing areas from São Paulo State

    Directory of Open Access Journals (Sweden)

    Renate Krause-Sakate

    2008-02-01

    Full Text Available Os sequivírus são vírus isométricos transmitidos por afídeos. Lettuce mottle virus (LeMoV, um provável sequivirus foi descrito no Brasil em 1982 e causa sintomas de mosaico semelhantes aos observados pelo Lettuce mosaic virus (LMV. Um levantamento para ocorrência do LeMoV nos campos de produção de alface de três diferentes regiões do Estado de São Paulo (Mogi das Cruzes, Campinas e Bauru foi realizado durante 2002 a 2005. RNA total foi extraído e utilizado na detecção, em RT-PCR, com oligonucleotídeos específicos para o LeMoV. Do total de 1362 amostras, 137 (10,05% foram positivas para o LeMoV. Infecção mista com o LMV foi verificada em 43 amostras (31,4%. Foi verificada a ocorrência do LeMoV nas três diferentes regiões analisadas, porém sua ocorrência foi baixa nas diferentes épocas do ano.Sequiviruses are isometric aphid-borne plant viruses. Lettuce mottle virus (LeMoV, a putative sequivirus was first described in Brazil on 1982 causing similar mosaic symptoms as Lettuce mosaic virus (LMV. A survey for the occurrence of LeMoV on open field conditions was carried out during 2002 to 2005 on Mogi das Cruzes, Campinas and Bauru in São Paulo state. Total RNA was extracted and used on RT-PCR with specific LeMoV primers. On 1362 samples tested, 137 (10,05% were positive for LeMoV. Mixed infections with LMV was observed on 43 samples (31,4%. The presence of LeMoV was observed in the three different regions, but with low incidence during the year.

  6. Characterization of a Nepovirus causing a leaf mottling disease in Petunia hybrida

    Science.gov (United States)

    This report describes the complete genome sequence and characterization of a new virus infecting petunia. Icosahedral virus-like particles were isolated from Petunia hybrida cuttings with interveinal chlorotic mottling. The virus was transmitted by mechanical inoculation from infected to healthy P. ...

  7. New Korean isolates of Pepper mild mottle virus (PMMoV) differ in symptom severity and subcellular localization of the 126 kDa protein

    Science.gov (United States)

    Two isolates of Pepper mild mottle virus (PMMoV) were selected from a nationwide survey of pepper fields in South Korea in 2014 and 2015, in which Cucumber mosaic virus was also detected; the two PMMoV isolates, Sangcheong 47 (S-47, KX399390) and Jeongsong 76 (J-76, KX399389), share ~99% nucleotide ...

  8. The complete nucleotide sequence of the genome of Barley yellow dwarf virus-RMV reveals it to be a new Polerovirus distantly related to other yellow dwarf viruses.

    Science.gov (United States)

    Krueger, Elizabeth N; Beckett, Randy J; Gray, Stewart M; Miller, W Allen

    2013-01-01

    The yellow dwarf viruses (YDVs) of the Luteoviridae family represent the most widespread group of cereal viruses worldwide. They include the Barley yellow dwarf viruses (BYDVs) of genus Luteovirus, the Cereal yellow dwarf viruses (CYDVs) and Wheat yellow dwarf virus (WYDV) of genus Polerovirus. All of these viruses are obligately aphid transmitted and phloem-limited. The first described YDVs (initially all called BYDV) were classified by their most efficient vector. One of these viruses, BYDV-RMV, is transmitted most efficiently by the corn leaf aphid, Rhopalosiphum maidis. Here we report the complete 5612 nucleotide sequence of the genomic RNA of a Montana isolate of BYDV-RMV (isolate RMV MTFE87, Genbank accession no. KC921392). The sequence revealed that BYDV-RMV is a polerovirus, but it is quite distantly related to the CYDVs or WYDV, which are very closely related to each other. Nor is BYDV-RMV closely related to any other particular polerovirus. Depending on the gene that is compared, different poleroviruses (none of them a YDV) share the most sequence similarity to BYDV-RMV. Because of its distant relationship to other YDVs, and because it commonly infects maize via its vector, R. maidis, we propose that BYDV-RMV be renamed Maize yellow dwarf virus-RMV (MYDV-RMV).

  9. The complete nucleotide sequence of the genome of Barley yellow dwarf virus-RMV reveals it to be a new Polerovirus distantly related to other yellow dwarf viruses

    Directory of Open Access Journals (Sweden)

    Elizabeth N. Krueger

    2013-07-01

    Full Text Available The yellow dwarf viruses (YDVs of the Luteoviridae family represent the most widespread group of cereal viruses worldwide. They include the Barley yellow dwarf viruses (BYDVs of genus Luteovirus, the Cereal yellow dwarf viruses (CYDVs and Wheat yellow dwarf virus (WYDV of genus Polerovirus. All of these viruses are obligately aphid transmitted and phloem-limited. The first described YDVs (initially all called BYDV were classified by their most efficient vector. One of these viruses, BYDV-RMV, is transmitted most efficiently by the corn leaf aphid, Rhopalosiphum maidis. Here we report the complete 5612 nucleotide sequence of the genomic RNA of a Montana isolate of BYDV-RMV (isolate RMV MTFE87, Genbank accession no. KC921392. The sequence revealed that BYDV-RMV is a polerovirus, but it is quite distantly related to the CYDVs or WYDV, which are very closely related to each other. Nor is BYDV-RMV closely related to any other particular polerovirus. Depending on the gene that is compared, different poleroviruses (none of them a YDV share the most sequence similarity to BYDV-RMV. Because of its distant relationship to other YDVs, and because it commonly infects maize via its vector, R. maidis, we propose that BYDV-RMV be renamed Maize yellow dwarf virus-RMV (MYDV-RMV.

  10. Colorimetric detection of Cucumber green mottle mosaic virus using unmodified gold nanoparticles as colorimetric probes.

    Science.gov (United States)

    Wang, Lin; Liu, Zhanmin; Xia, Xueying; Yang, Cuiyun; Huang, Junyi; Wan, Sibao

    2017-05-01

    Cucumber green mottle mosaic virus (CGMMV)causes a severe mosaic symptom of watermelon and cucumber, and can be transmitted via infected cucumber seeds, leaves and soil. It remains a challenge to detect this virus to prevent its introduction and infection and spread in fields. For this purpose, a simple and sensitive label-free colorimetric detection method for CGMMV has been developed with unmodified gold nanoparticles (AuNPs) as colorimetric probes. The method is based on the finding that the presence of RT-PCR target products of CGMMV and species-specific probes results in color change of AuNPs from red to blue after NaCl induction. Normally, species-specific probes attach to the surface of AuNPs and thereby increasing their resistance to NaCl-induced aggregation. The concentration of sodium, probes in the reaction system and evaluation of specificity and sensitivity of a novel assay, visual detection of Cucumber green mottle mosaic virus using unmodified AuNPs has been carried out with simple preparation of samples in our study. Through this assay, as low as 30pg/μL of CGMMV RNA was thus detected visually, by the naked eye, without the need for any sophisticated, expensive instrumentation and biochemical reagents. The specificity was 100% and exhibited good reproducibility in our assays. The results note that this assay is highly species-specific, simple, low-cost, and visual for easy detection of CGMMV in plant tissues. Therefore, visual assay is a potentially useful tool for middle or small-scales corporations and entry-exit inspection and quarantine bureau to detect CGMMV in cucumber seeds or plant tissues. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. Association of an Alphasatellite with Tomato Yellow Leaf Curl Virus and Ageratum Yellow Vein Virus in Japan is Suggestive of a Recent Introduction

    OpenAIRE

    Shahid, Muhammad Shafiq; Ikegami, Masato; Waheed, Abdul; Briddon, Rob W.; Natsuaki, Keiko T.

    2014-01-01

    Samples were collected in 2011 from tomato plants exhibiting typical tomato leaf curl disease symptoms in the vicinity of Komae, Japan. PCR mediated amplification, cloning and sequencing of all begomovirus components from two plants from different fields showed the plants to be infected by Tomato yellow leaf curl virus (TYLCV) and Ageratum yellow vein virus (AYVV). Both viruses have previously been shown to be present in Japan, although this is the first identification of AYVV on mainland Jap...

  12. Infection of Mosquito Cells (C6/36) by Dengue-2 Virus Interferes with Subsequent Infection by Yellow Fever Virus.

    Science.gov (United States)

    Abrao, Emiliana Pereira; da Fonseca, Benedito Antônio Lopes

    2016-02-01

    Dengue is one of the most important diseases caused by arboviruses in the world. Yellow fever is another arthropod-borne disease of great importance to public health that is endemic to tropical regions of Africa and the Americas. Both yellow fever and dengue viruses are flaviviruses transmitted by Aedes aegypti mosquitoes, and then, it is reasonable to consider that in a given moment, mosquito cells could be coinfected by both viruses. Therefore, we decided to evaluate if sequential infections of dengue and yellow fever viruses (and vice-versa) in mosquito cells could affect the virus replication patterns. Using immunofluorescence and real-time PCR-based replication assays in Aedes albopictus C6/36 cells with single or sequential infections with both viruses, we demonstrated the occurrence of viral interference, also called superinfection exclusion, between these two viruses. Our results show that this interference pattern is particularly evident when cells were first infected with dengue virus and subsequently with yellow fever virus (YFV). Reduction in dengue virus replication, although to a lower extent, was also observed when C6/36 cells were initially infected with YFV followed by dengue virus infection. Although the importance that these findings have on nature is unknown, this study provides evidence, at the cellular level, of the occurrence of replication interference between dengue and yellow fever viruses and raises the question if superinfection exclusion could be a possible explanation, at least partially, for the reported lack of urban yellow fever occurrence in regions where a high level of dengue transmission occurs.

  13. pathogenecity of two strains of rice yellow mottle virus on aromatic

    African Journals Online (AJOL)

    Mgina

    Valley), Arusha (Ndungu Plains) including parts of Shinyanga and Mwanza regions where the virus induces severe yield losses in farmers' fields. RYMV is a member of the genus. Sobemovirus. ... with contrasting ecological, geographical distribution within a ... importance in country's rice cropping systems. Existing in ...

  14. Differentiation of strains of yellow fever virus in γ-irradiated mice

    International Nuclear Information System (INIS)

    Fitzgeorge, R.; Bradish, C.J.

    1980-01-01

    The mouse sensitized by optimal, sub-lethal γ-irradiation has been used for the differentiation of strains of yellow fever virus and for the resolution of their immunogenicity and pathogenicity as distinct characteristics. For different strains of yellow fever virus, the patterns of antibody-synthesis, regulatory immunity (pre-challenge) and protective immunity (post-challenge) are differentially sensitive to γ-irradiation. These critical differentiations of strains of yellow fever virus in γ-irradiated mice have been compared with those shown in normal athymic and immature mice in order to elucidate the range of quantifiable in vivo characteristics and the course of the virus-host interaction. This is discussed as a basis for the comparisons of the responses of model and principal hosts to vaccines and pathogens. (author)

  15. Association of an alphasatellite with tomato yellow leaf curl virus and ageratum yellow vein virus in Japan is suggestive of a recent introduction.

    Science.gov (United States)

    Shahid, Muhammad Shafiq; Ikegami, Masato; Waheed, Abdul; Briddon, Rob W; Natsuaki, Keiko T

    2014-01-14

    Samples were collected in 2011 from tomato plants exhibiting typical tomato leaf curl disease symptoms in the vicinity of Komae, Japan. PCR mediated amplification, cloning and sequencing of all begomovirus components from two plants from different fields showed the plants to be infected by Tomato yellow leaf curl virus (TYLCV) and Ageratum yellow vein virus (AYVV). Both viruses have previously been shown to be present in Japan, although this is the first identification of AYVV on mainland Japan; the virus previously having been shown to be present on the Okinawa Islands. The plant harboring AYVV was also shown to contain the betasatellite Tomato leaf curl Java betasatellite (ToLCJaB), a satellite not previously shown to be present in Japan. No betasatellite was associated with the TYLCV infected tomato plants analyzed here, consistent with earlier findings for this virus in Japan. Surprisingly both plants were also found to harbor an alphasatellite; no alphasatellites having previously been reported from Japan. The alphasatellite associated with both viruses was shown to be Sida yellow vein China alphasatellite which has previously only been identified in the Yunnan Province of China and Nepal. The results suggest that further begomoviruses, and their associated satellites, are being introduced to Japan. The significance of these findings is discussed.

  16. Association of an Alphasatellite with Tomato Yellow Leaf Curl Virus and Ageratum Yellow Vein Virus in Japan Is Suggestive of a Recent Introduction

    Directory of Open Access Journals (Sweden)

    Muhammad Shafiq Shahid

    2014-01-01

    Full Text Available Samples were collected in 2011 from tomato plants exhibiting typical tomato leaf curl disease symptoms in the vicinity of Komae, Japan. PCR mediated amplification, cloning and sequencing of all begomovirus components from two plants from different fields showed the plants to be infected by Tomato yellow leaf curl virus (TYLCV and Ageratum yellow vein virus (AYVV. Both viruses have previously been shown to be present in Japan, although this is the first identification of AYVV on mainland Japan; the virus previously having been shown to be present on the Okinawa Islands. The plant harboring AYVV was also shown to contain the betasatellite Tomato leaf curl Java betasatellite (ToLCJaB, a satellite not previously shown to be present in Japan. No betasatellite was associated with the TYLCV infected tomato plants analyzed here, consistent with earlier findings for this virus in Japan. Surprisingly both plants were also found to harbor an alphasatellite; no alphasatellites having previously been reported from Japan. The alphasatellite associated with both viruses was shown to be Sida yellow vein China alphasatellite which has previously only been identified in the Yunnan Province of China and Nepal. The results suggest that further begomoviruses, and their associated satellites, are being introduced to Japan. The significance of these findings is discussed.

  17. Transmission of yellow fever vaccine virus through breast-feeding - Brazil, 2009.

    Science.gov (United States)

    2010-02-12

    In April, 2009, the state health department of Rio Grande do Sul, Brazil, was notified by the Cachoeira do Sul municipal health department of a case of meningoencephalitis requiring hospitalization in an infant whose mother recently had received yellow fever vaccine during a postpartum visit. The Field Epidemiology Training Program of the Secretariat of Surveillance in Health of the Brazilian Ministry of Health assisted state and municipal health departments with an investigation. This report summarizes the results of that investigation, which determined that the infant acquired yellow fever vaccine virus through breast-feeding. The mother reported 2 days of headache, malaise, and low fever occurring 5 days after receipt of yellow fever vaccine. The infant, who was exclusively breast-fed, was hospitalized at age 23 days with seizures requiring continuous infusion of intravenous anticonvulsants. The infant received antimicrobial and antiviral treatment for meningoencephalitis. The presence of 17DD yellow fever virus was detected by reverse transcription--polymerase chain reaction (RT-PCR) in the infant's cerebrospinal fluid (CSF); yellow fever--specific immunoglobulin M (IgM) antibodies also were present in serum and CSF. The infant recovered completely, was discharged after 24 days of hospitalization, and has had normal neurodevelopment and growth through age 6 months. The findings in this report provide documentation that yellow fever vaccine virus can be transmitted via breast-feeding. Administration of yellow fever vaccine to breast-feeding women should be avoided except in situations where exposure to yellow fever viruses cannot be avoided or postponed.

  18. Characterization of burdock mottle virus, a novel member of the genus Benyvirus, and the identification of benyvirus-related sequences in the plant and insect genomes.

    Science.gov (United States)

    Kondo, Hideki; Hirano, Shuichi; Chiba, Sotaro; Andika, Ida Bagus; Hirai, Makoto; Maeda, Takanori; Tamada, Tetsuo

    2013-10-01

    The complete nucleotide sequence of the burdock mottle virus (BdMoV) isolated from an edible burdock plant (Arctium lappa) in Japan has been determined. BdMoV has a bipartite genome, whose organization is similar to RNA1 and RNA2 of benyviruses, beet necrotic yellow vein virus (BNYVV), beet soil-borne mosaic virus (BSBMV), and rice stripe necrosis virus (RSNV). BdMoV RNA1 (7038 nt) contains a single open reading frame (ORF) encoding a 249-kDa polypeptide that consists of methyl-transferase, helicase, papain-like protease, AlkB-like, and RNA-dependent RNA polymerase domains. The AlkB-like domain sequence is not present in the proteins encoded by other known benyviruses, but is found in replication-associated proteins of viruses mainly belonging to the families Alfaflexiviridae and Betaflexiviridae. BdMoV RNA2 (4315 nt) contains six ORFs that are similar to those of benyviruses: these are coat protein (CP), CP readthrough, triple gene block movement and cysteine-rich proteins. Phylogenetic analyses showed that BdMoV is more closely related to BNYVV and BSBMV than to RSNV. Database searches showed that benyvirus replicase-related sequences are present in the chromosomes of a chickpea plant (Cicer arietinum) and a blood-sucking insect (Rhodnius prolixus). Some other benyvirus-related sequences are found in the transcriptome shotgun libraries of a few species of plants and a bark beetle. Our results show that BdMoV is a distinct species of the genus Benyvirus and that ancestral and extant benyviruses may have infected or currently infect a wide range of hosts, including plants and insects. Copyright © 2013 Elsevier B.V. All rights reserved.

  19. Multiple loci condition seed transmission of soybean mosaic virus (SMV) and SMV-induced seed coat mottling in soybean.

    Science.gov (United States)

    Domier, Leslie L; Hobbs, Houston A; McCoppin, Nancy K; Bowen, Charles R; Steinlage, Todd A; Chang, Sungyul; Wang, Yi; Hartman, Glen L

    2011-06-01

    Infection of soybean plants with Soybean mosaic virus (SMV), which is transmitted by aphids and through seed, can cause significant reductions in seed production and quality. Because seedborne infections are the primary sources of inoculum for SMV infections in North America, host-plant resistance to seed transmission can limit the pool of plants that can serve as sources of inoculum. To examine the inheritance of SMV seed transmission in soybean, crosses were made between plant introductions (PIs) with high (PI88799), moderate (PI60279), and low (PI548391) rates of transmission of SMV through seed. In four F(2) populations, SMV seed transmission segregated as if conditioned by two or more genes. Consequently, a recombinant inbred line population was derived from a cross between PIs 88799 and 548391 and evaluated for segregation of SMV seed transmission, seed coat mottling, and simple sequence repeat markers. Chromosomal regions on linkage groups C1 and C2 were significantly associated with both transmission of isolate SMV 413 through seed and SMV-induced seed coat mottling, and explained ≈42.8 and 46.4% of the variability in these two traits, respectively. Chromosomal regions associated with seed transmission and seed coat mottling contained homologues of Arabidopsis genes DCL3 and RDR6, which encode enzymes involved in RNA-mediated transcriptional and posttranscriptional gene silencing.

  20. Papaya Lethal Yellowing Virus (PLYV) Infects Vasconcellea cauliflora

    NARCIS (Netherlands)

    Amaral, P.P.R.; Resende, de R.O.; Souza, M.T.

    2006-01-01

    Papaya lethal yellowing virus (PLYV) é um dos três vírus descritos infectando mamoeiros (Carica papaya L.) no Brasil. Vasconcellea cauliflora (Jacq.) A. DC., antes denominada de Carica cauliflora (Jacq.), é uma reconhecida fonte de resistência natural ao Papaya ringspot virus (PRSV), causador da

  1. T Cell-Mediated Immunity towards Yellow Fever Virus and Useful Animal Models.

    Science.gov (United States)

    Watson, Alan M; Klimstra, William B

    2017-04-11

    The 17D line of yellow fever virus vaccines is among the most effective vaccines ever created. The humoral and cellular immunity elicited by 17D has been well characterized in humans. Neutralizing antibodies have long been known to provide protection against challenge with a wild-type virus. However, a well characterized T cell immune response that is robust, long-lived and polyfunctional is also elicited by 17D. It remains unclear whether this arm of immunity is protective following challenge with a wild-type virus. Here we introduce the 17D line of yellow fever virus vaccines, describe the current state of knowledge regarding the immunity directed towards the vaccines in humans and conclude with a discussion of animal models that are useful for evaluating T cell-mediated immune protection to yellow fever virus.

  2. Begomoviruses infecting weeds in Cuba: increased host range and a novel virus infecting Sida rhombifolia.

    Science.gov (United States)

    Fiallo-Olivé, Elvira; Navas-Castillo, Jesús; Moriones, Enrique; Martínez-Zubiaur, Yamila

    2012-01-01

    As a result of surveys conducted during the last few years to search for wild reservoirs of begomoviruses in Cuba, we detected a novel bipartite begomovirus, sida yellow mottle virus (SiYMoV), infecting Sida rhombifolia plants. The complete genome sequence was obtained, showing that DNA-A was 2622 nucleotides (nt) in length and that it was most closely related (87.6% nucleotide identity) to DNA-A of an isolate of sida golden mosaic virus (SiGMV) that infects snap beans (Phaseolus vulgaris) in Florida. The DNA-B sequence was 2600 nt in length and shared the highest nucleotide identity (75.1%) with corchorus yellow spot virus (CoYSV). Phylogenetic relationship analysis showed that both DNA components of SiYMoV were grouped in the Abutilon clade, along with begomoviruses from Florida and the Caribbean islands. We also present here the complete nucleotide sequence of a novel strain of sida yellow vein virus found infecting Malvastrum coromandelianum and an isolate of euphorbia mosaic virus that was found for the first time infecting Euphorbia heterophylla in Cuba.

  3. Structural rigidity in the capsid assembly of cowpea chlorotic mottle virus

    International Nuclear Information System (INIS)

    Hespenheide, B M; Jacobs, D J; Thorpe, M F

    2004-01-01

    The cowpea chlorotic mottle virus (CCMV) has a protein cage, or capsid, which encloses its genetic material. The structure of the capsid consists of 180 copies of a single protein that self-assemble inside a cell to form a complete capsid with icosahedral symmetry. The icosahedral surface can be naturally divided into pentagonal and hexagonal faces, and the formation of either of these faces has been proposed to be the first step in the capsid assembly process. We have used the software FIRST to analyse the rigidity of pentameric and hexameric substructures of the complete capsid to explore the viability of certain capsid assembly pathways. FIRST uses the 3D pebble game to determine structural rigidity, and a brief description of this algorithm, as applied to body-bar networks, is given here. We find that the pentameric substructure, which corresponds to a pentagonal face on the icosahedral surface, provides the best structural properties for nucleating the capsid assembly process, consistent with experimental observations

  4. Structural rigidity in the capsid assembly of cowpea chlorotic mottle virus

    Science.gov (United States)

    Hespenheide, B. M.; Jacobs, D. J.; Thorpe, M. F.

    2004-11-01

    The cowpea chlorotic mottle virus (CCMV) has a protein cage, or capsid, which encloses its genetic material. The structure of the capsid consists of 180 copies of a single protein that self-assemble inside a cell to form a complete capsid with icosahedral symmetry. The icosahedral surface can be naturally divided into pentagonal and hexagonal faces, and the formation of either of these faces has been proposed to be the first step in the capsid assembly process. We have used the software FIRST to analyse the rigidity of pentameric and hexameric substructures of the complete capsid to explore the viability of certain capsid assembly pathways. FIRST uses the 3D pebble game to determine structural rigidity, and a brief description of this algorithm, as applied to body-bar networks, is given here. We find that the pentameric substructure, which corresponds to a pentagonal face on the icosahedral surface, provides the best structural properties for nucleating the capsid assembly process, consistent with experimental observations.

  5. Structural rigidity in the capsid assembly of cowpea chlorotic mottle virus

    Energy Technology Data Exchange (ETDEWEB)

    Hespenheide, B M [Department of Physics and Astronomy, Arizona State University, PO Box 871504, Tempe, AZ 85287-1504 (United States); Jacobs, D J [Department of Physics and Astronomy, California State University, 18111 Nordhoff Street, Northridge, CA 91330-8268 (United States); Thorpe, M F [Department of Physics and Astronomy, Arizona State University, PO Box 871504, Tempe, AZ 85287-1504 (United States)

    2004-11-10

    The cowpea chlorotic mottle virus (CCMV) has a protein cage, or capsid, which encloses its genetic material. The structure of the capsid consists of 180 copies of a single protein that self-assemble inside a cell to form a complete capsid with icosahedral symmetry. The icosahedral surface can be naturally divided into pentagonal and hexagonal faces, and the formation of either of these faces has been proposed to be the first step in the capsid assembly process. We have used the software FIRST to analyse the rigidity of pentameric and hexameric substructures of the complete capsid to explore the viability of certain capsid assembly pathways. FIRST uses the 3D pebble game to determine structural rigidity, and a brief description of this algorithm, as applied to body-bar networks, is given here. We find that the pentameric substructure, which corresponds to a pentagonal face on the icosahedral surface, provides the best structural properties for nucleating the capsid assembly process, consistent with experimental observations.

  6. T Cell-Mediated Immunity towards Yellow Fever Virus and Useful Animal Models

    Science.gov (United States)

    Watson, Alan M.; Klimstra, William B.

    2017-01-01

    The 17D line of yellow fever virus vaccines is among the most effective vaccines ever created. The humoral and cellular immunity elicited by 17D has been well characterized in humans. Neutralizing antibodies have long been known to provide protection against challenge with a wild-type virus. However, a well characterized T cell immune response that is robust, long-lived and polyfunctional is also elicited by 17D. It remains unclear whether this arm of immunity is protective following challenge with a wild-type virus. Here we introduce the 17D line of yellow fever virus vaccines, describe the current state of knowledge regarding the immunity directed towards the vaccines in humans and conclude with a discussion of animal models that are useful for evaluating T cell-mediated immune protection to yellow fever virus. PMID:28398253

  7. Occurrence of pepper mild mottle virus in greenhousegrown pepper ...

    African Journals Online (AJOL)

    Severe systemic viral symptoms were observed on the leaves of infected pepper (Capsicum annuum L.) plants cultivated in Antalya located in the Mediterranean coast of Turkey, in 2008. The symptoms on the diseased pepper plants included, mosaic, mottle, chlorosis coupled with stunting, chlorotic spots, distortion of the ...

  8. Characterization of petunia flower mottle virus (PetFMV), a new potyvirus infecting Petunia x hybrida.

    Science.gov (United States)

    Feldhoff, A; Wetzel, T; Peters, D; Kellner, R; Krczal, G

    1998-01-01

    With the introduction of cutting-grown Petunia x hybrida plants on the European market, a new potyvirus which showed no serological reaction with antisera against any other potyviruses infecting petunias was discovered. Infected leaves contained flexuous rod-shaped virus particles of 750-800 nm in length and inclusion bodies (pinwheel structures) typical for potyviruses in ultrathin leaf sections. The purified coat protein with a Mr of approximately 36 kDa could be detected in Western immunoblots with a specific antibody to the coat protein of the petunia-infecting virus. The 3' end of the viral genome encompassing the 3' non-coding region, the coat protein gene, and part of the NIb gene was amplified from infected leaf material by IC/PCR using degenerate and specific primers. Sequences of PCR-generated cDNA clones were compared to other known sequences of potyviruses. Maximum homology of 56% was found in the 3' non-coding region between the petunia isolate and other potyviruses. A maximum homology of 69% was found between the amino acid sequence of the coat protein of the petunia isolate and corresponding sequences of other potyviruses. These data indicate that the petunia-infecting virus is a previously undescribed potyvirus and the name petunia flower mottle virus (PetFMV) is suggested.

  9. Passion Fruit Chlorotic Mottle Virus: Molecular Characterization of a New Divergent Geminivirus in Brazil.

    Science.gov (United States)

    Fontenele, Rafaela S; Abreu, Rayane A; Lamas, Natalia S; Alves-Freitas, Dione M T; Vidal, Andreza H; Poppiel, Raul R; Melo, Fernando L; Lacorte, Cristiano; Martin, Darren P; Campos, Magnolia A; Varsani, Arvind; Ribeiro, Simone G

    2018-04-02

    Brazil is one of the major passion fruit producers worldwide. Viral diseases are among the most important constraints for passion fruit production. Here we identify and characterize a new passion fruit infecting-virus belonging to the family Geminiviridae : passion fruit chlorotic mottle virus (PCMoV). PCMoV is a divergent geminivirus unlike previously characterized passion fruit-infecting geminiviruses that belonged to the genus Begomovirus . Among the presently known geminiviruses, it is most closely related to, and shares ~62% genome-wide identity with citrus chlorotic dwarf associated virus (CCDaV) and camelia chlorotic dwarf associated virus (CaCDaV). The 3743 nt PCMoV genome encodes a capsid protein (CP) and replication-associated protein (Rep) that respectively share 56 and 60% amino acid identity with those encoded by CaCDaV. The CPs of PCMoV, CCDaV, and CaCDaV cluster with those of begomovirus whereas their Reps with those of becurtoviruses. Hence, these viruses likely represent a lineage of recombinant begomo-like and becurto-like ancestral viruses. Furthermore, PCMoV, CCDaV, and CaCDaV genomes are ~12-30% larger than monopartite geminiviruses and this is primarily due to the encoded movement protein (MP; 891-921 nt) and this MP is most closely related to that encoded by the DNA-B component of bipartite begomoviruses. Hence, PCMoV, CCDaV, and CaCDaV lineage of viruses may represent molecules in an intermediary step in the evolution of bipartite begomoviruses (~5.3 kb) from monopartite geminiviruses (~2.7-3 kb). An infectious clone of PCMoV systemically infected Nicotiana benthamina , Arabidopsis thaliana , and Passiflora edulis .

  10. Ocorrência do vírus do mosqueado do morangueiro no estado de São Paulo Occurrence of the strawberry mottle virus in São Paulo

    Directory of Open Access Journals (Sweden)

    Ana Maria B. Carvalho

    1961-01-01

    Full Text Available Verificou-se a ocorrência de estirpes do vírus do grupo denominado mosqueado («strawberry mottle» em plantações de morangueiro no Estado de São Paulo. Variedades antigas, como a Dr. Morère. acham-se totalmente infetatas. sendo portadoras sem sintomas. Alguns clones novos plantados apenas por poucos anos em campo, já se acham parcialmente infetados, indicando que há transmissão da moléstia sob condições naturais. Sintomas de palidez das nervuras, mosqueado, paralisação no crescimento e encrespamento são apresentados por plantas de Fragaria vesca infetadas pelos vírus dêsse grupo. Numerosas espécies de plantas-teste habituais foram inoculadas com diferentes isolados do vírus, por meio do vetor, mas os resultados foram geralmente negativos. Afídios virulíferos, colonizados sôbre plantas novas de Cassia accidentalis, Chenopodiam quinoa, Leonotis nepaetifolia e Leonurus sibiricus. induziram o aparecimento de sintomas. Não se conseguiu retransmitir o vírus dessas espécies para F. vesca, existindo, portanto, dúvidas sôbre a verdadeira identidade do vírus que infetava tais plantas. O vírus do mosqueado não foi aparentemente transmitido pela semente. Também não se mostrou transmissível mecânicamente para Frogaria vesca. O virus obtido por inoculação com o vetor em Chenopodium quinoa e que se supõe ser o do mosqueado, pôde se transmitido mecânicamente de C. quinoa para C. quinoa. mas não para F. vesca. O pulgão Pentatrichopus fragaefolii mostrou-se eficiente vetor do mosqueado, conseguindo-se obter em média mais de 50% de infecção em infestações com 1 afidio por planta. Aphis gossypii também transmitiu o vírus do mosqueado, mas com muito menor eficiência. Não se conseguiu transmitir o mosqueado com uma espécie de Cuscuta que ocorre comumeute em Campinas. Em testes de transmissão por enxertia de fôlhas, os resultados foram muito fracos devido ao mau pegamento. O pulgão Pentatrichopus fragaefolii

  11. First Report of Cowpea Mild Mottle Carlavirus on Yardlong Bean (Vigna unguiculata subsp. sesquipedalis in Venezuela

    Directory of Open Access Journals (Sweden)

    Edgloris Marys

    2012-12-01

    Full Text Available Yardlong bean (Vigna unguiculata subsp. sesquipedalis plants with virus-like systemic mottling and leaf distortion were observed in both experimental and commercial fields in Aragua State, Venezuela. Symptomatic leaves were shown to contain carlavirus-like particles. RT-PCR analysis with carlavirus-specific primers was positive in all tested samples. Nucleotide sequences of the obtained amplicons showed 84%–74% similarity to corresponding sequences of Cowpea mild mottle virus (CPMMV isolates deposited in the GenBank database. This is the first report of CPMMV in Venezuela and is thought to be the first report of CPMMV infecting yardlong bean.

  12. Susceptibility of Koi and Yellow Perch to infectious hematopoietic necrosis virus by experimental exposure

    Science.gov (United States)

    Palmer, Alexander D.; Emmenegger, Eveline J.

    2014-01-01

    Infectious hematopoietic necrosis virus (IHNV) is a novirhabdoviral pathogen that originated in western North America among anadromous Pacific salmonids. Severe disease epidemics in the late 1970s resulting from IHNV's invasion into farmed Rainbow Trout Oncorhynchus mykiss in North America, Asia, and Europe emphasized IHNV's ability to adapt to new hosts under varying rearing conditions. Yellow Perch Perca flavescens and Koi Carp Cyprinus carpio (hereafter, “Koi”) are aquaculture-reared fish that are highly valued in sport fisheries and the ornamental fish trade, respectively, but it is unknown whether these fish species are vulnerable to IHNV infection. In this study, we exposed Yellow Perch, Koi, and steelhead (anadromous Rainbow Trout) to IHNV by intraperitoneal injection (106 PFU/fish) and by immersion (5.7×105 PFU/mL) for 7 h, and monitored fish for 28 d. The extended immersion exposure and high virus concentrations used in the challenges were to determine if the tested fish had any level of susceptibility. After experimental exposure, Yellow Perch and Koi experienced low mortality (35%). Virus was found in dead fish of all species tested and in surviving Yellow Perch by plaque assay and quantitative reverse transcription polymerase chain reaction (qPCR), with a higher prevalence in Yellow Perch than Koi. Infectious virus was also detected in Yellow Perch out to 5 d after bath challenge. These findings indicate that Yellow Perch and Koi are highly resistant to IHNV disease under the conditions tested, but Yellow Perch are susceptible to infection and may serve as possible virus carriers.

  13. Enzootic transmission of yellow fever virus, Venezuela.

    Science.gov (United States)

    Auguste, Albert J; Lemey, Philippe; Bergren, Nicholas A; Giambalvo, Dileyvic; Moncada, Maria; Morón, Dulce; Hernandez, Rosa; Navarro, Juan-Carlos; Weaver, Scott C

    2015-01-01

    Phylogenetic analysis of yellow fever virus (YFV) strains isolated from Venezuela strongly supports YFV maintenance in situ in Venezuela, with evidence of regionally independent evolution within the country. However, there is considerable YFV movement from Brazil to Venezuela and between Trinidad and Venezuela.

  14. Image mottle in abdominal CT.

    Science.gov (United States)

    Ende, J F; Huda, W; Ros, P R; Litwiller, A L

    1999-04-01

    To investigate image mottle in conventional CT images of the abdomen as a function of radiographic technique factors and patient size. Water-filled phantoms simulating the abdomens of adult (32 cm in diameter) and pediatric (16 cm in diameter) patients were used to investigate image mottle in CT as a function of x-ray tube potential and mAs. CT images from 39 consecutive patients with noncontrast liver scans and 49 patients with iodine contrast scans were analyzed retrospectively. Measurements were made of the mean liver parenchyma Hounsfield unit value and the corresponding image mottle. For a given water phantom and x-ray tube potential, image mottle was proportional to the mAs-0.5. Increasing the phantom diameter from 16 cm (pediatric) to 32 cm increased the mottle by a factor of 2.4, and increasing the x-ray tube potential from 80 kVp to 140 kVp reduced the mottle by a factor of 2.5. All patients were scanned at 120 kVp, with no correlation between patient size and the x-ray tube mAs. The mean mottle level was 7.8 +/- 2.2 and 10.0 +/- 2.5 for the noncontrast and contrast studies, respectively. An increase in patient diameter of 3 cm would require approximately 65% more mAs to maintain the same level of image mottle. The mottle in abdominal CT images may be controlled by adjusting radiographic technique factors, which should be adjusted to take into account the size of the patient undergoing the examination.

  15. Different virus-derived siRNAs profiles between leaves and fruits in Cucumber green mottle mosaic virus-infected Lagenaria siceraria

    Directory of Open Access Journals (Sweden)

    Junmin Li

    2016-11-01

    Full Text Available RNA silencing is an evolutionarily conserved antiviral mechanism, through which virus-derived small interfering RNAs (vsiRNAs playing roles in host antiviral defence are produced in virus-infected plant. Deep sequencing technology has revolutionized the study on the interaction between virus and plant host through the analysis of vsiRNAs profile. However, comparison of vsiRNA profiles in different tissues from a same host plant has been rarely reported. In this study, the profiles of virus-derived small interfering RNAs (vsiRNAs from leaves and fruits of Lagenaria siceraria plants infected with Cucumber green mottle mosaic virus (CGMMV were comprehensively characterized and compared. Many more vsiRNAs were present in infected leaves than in fruits. vsiRNAs from both leaves and fruits were mostly 21- and 22-nt in size as previously described in other virus-infected plants. Interestingly, vsiRNAs were predominantly produced from the viral positive strand RNAs in infected leaves, whereas in infected fruits they were derived equally from the positive and negative strands. Many leaf-specific positive vsiRNAs with lengths of 21-nt (2,058 or 22-nt (3,996 were identified but only six (21-nt and one (22-nt positive vsiRNAs were found to be specific to fruits. vsiRNAs hotspots were only present in the 5’-terminal and 3’-terminal of viral positive strand in fruits, while multiple hotspots were identified in leaves. Differences in GC content and 5'-terminal nucleotide of vsiRNAs were also observed in the two organs. To our knowledge, this provides the first high-resolution comparison of vsiRNA profiles between different tissues of the same host plant.

  16. Complete nucleotide sequences and construction of full-length infectious cDNA clones of Cucumber green mottle virus (CGMMV) in a versatile newly developed binary vector including both 35S and T7 promoters

    Science.gov (United States)

    Seed-transmitted viruses have caused significant damage to watermelon crops in Korea in recent years, with Cucumber green mottle mosaic virus (CGMMV) infection widespread as a result of infected seed lots. To determine the likely origin of CGMMV infection, we collected CGMMV isolates from watermelon...

  17. Characteristics of rose mosaic diseases

    Directory of Open Access Journals (Sweden)

    Marek S. Szyndel

    2013-12-01

    Full Text Available Presented review of rose diseases, associated with the mosaic symptoms, includes common and yellow rose mosaic, rose ring pattern, rose X disease, rose line pattern, yellow vein mosaic and rose mottle mosaic disease. Based on symptomatology and graft transmissibility of causing agent many of those rose disorders are called "virus-like diseases" since the pathogen has never been identified. However, several viruses were detected and identified in roses expressing mosaic symptoms. Currently the most prevalent rose viruses are Prunus necrotic ringspot virus - PNRSV, Apple mosaic virus - ApMV (syn. Rose mosaic virus and Arabis mosaic virus - ArMV Symptoms and damages caused by these viruses are described. Tomato ringspot virus, Tobacco ringspot virus and Rose mottle mosaic virus are also mentioned as rose pa thogcns. Methods of control of rose mosaic diseases are discussed.

  18. First report of Sugarcane yellow leaf virus infecting Columbus Grass (Sorghum almum) in Florida

    Science.gov (United States)

    Sugarcane yellow leaf virus (SCYLV) [genus Polerovirus, family Luteoviridae] is the causal agent of sugarcane yellow leaf disease. SCYLV is widespread in Florida where sugarcane was the only known natural host of this virus. During spring 2015, we collected (leaves or stalks) and tested several gras...

  19. Yellow Fever Virus Vaccine–associated Deaths in Young Women 1

    OpenAIRE

    Seligman, Stephen J.

    2011-01-01

    Yellow fever vaccine–associated viscerotropic disease is a rare sequela of live-attenuated virus vaccine. Elderly persons and persons who have had thymectomies have increased susceptibility. A review of published and other data suggested a higher than expected number of deaths from yellow fever vaccine–associated viscerotropic disease among women 19–34 years of age without known immunodeficiency.

  20. Detection of yellow fever virus genomes from four imported cases in China.

    Science.gov (United States)

    Cui, Shujuan; Pan, Yang; Lyu, Yanning; Liang, Zhichao; Li, Jie; Sun, Yulan; Dou, Xiangfeng; Tian, Lili; Huo, Da; Chen, Lijuan; Li, Xinyu; Wang, Quanyi

    2017-07-01

    Yellow fever virus (YFV), as the first proven human-pathogenic virus, is still a major public health problem with a dramatic upsurge in recent years. This is a report on four imported cases of yellow fever virus into China identified by whole genome sequencing. Phylogenetic analysis was performed and the results showed that these four viruses were highly homologous with Angola 71 strains (AY968064). In addition, effective mutations of amino acids were not observed in the E protein domain of four viruses, thus confirming the effectiveness of the YFV-17D vaccine (X03700). Although there is low risk of local transmission in most part of China, the increasing public health risk of YF caused by international exchange should not be ignored. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  1. Detection of yellow dwarf virus onion (OYDV) and garlic common latent virus (GCLV) in Costa Rican garlic (Allium sativum L)

    International Nuclear Information System (INIS)

    Guillen Watson, Anny Vannesa; Chacon Cerdas, Randall; Zuniga Vega, Claudia

    2011-01-01

    Viral diseases have been responsible for significant losses in crop yield of garlic in the world. Costa Rican material Garlic has been analyzed to determine the incidence of : onion yellow dwarf virus (OYDV), the leek yellow stripe virus (LYSV), shallot latent virus (SLV) and garlic common latent virus (GLCV). The DAS-ELISA technique has been used for status native plant material. Bulbs field apparently normal (N), normal with yellow tunic (TA) and deformed (D) and normal field sheets (N), symptomatic (S) and possible presence of viral vectors (VT) were used. Vitroplants product have analyzed the introduction of apices of 1,0 and 0,5 cm in length teeth from normal (N) and yellow tunic (TA). The 33% of the bulbs GCLV field were analyzed for positive (TA), whereas OYDV was detected 100% appearance regardless. 100% of the plantlets have presented without infection of GCLV, the OYDV only those introduced in apices of 1,0 cm from bulbs with yellow robes have shown without effect. GCLV is determined for 100% of the samples for both batches OYDV bulb formation in vitro and in only 50%. In the Costa Rican garlic has concluded that are present the viruses of GCLV and OYDV, with a high incidence on local material and differential infection according to the organ analyzed. Various methodologies combined are recommended together with the apexes vitro cultivation, for more effective viral clearance and thus increase the value and boost the local seed crop. (author) [es

  2. Status of Sugarcane yellow leaf virus and its impact in different progenies

    Science.gov (United States)

    Yellow leaf disease caused by Sugarcane yellow leaf virus (SCYLV) a Polerovirus is an important disease for sugarcane industries worldwide. High yield losses up to 50% were reported in susceptible varieties. Most of the commercial cultivars in Florida are infected with SCYLV; therefore, there is a ...

  3. Molecular and Ultrastructural Mechanisms Underlying Yellow Dwarf Symptom Formation in Wheat after Infection of Barley Yellow Dwarf Virus.

    Science.gov (United States)

    Rong, Wei; Wang, Xindong; Wang, Xifeng; Massart, Sebastien; Zhang, Zengyan

    2018-04-13

    Wheat ( Tritium aestivum L.) production is essential for global food security. Infection of barley yellow dwarf virus-GAV (BYDV-GAV) results in wheat showing leaf yellowing and plant dwarfism symptom. To explore the molecular and ultrastructural mechanisms underlying yellow dwarf symptom formation in BYDV-GAV-infected wheat, we investigated the chloroplast ultrastructure via transmission electron microscopy (TEM), examined the contents of the virus, H₂O₂, and chlorophyll in Zhong8601, and studied the comparative transcriptome through microarray analyses in the susceptible wheat line Zhong8601 after virus infection. TEM images indicated that chloroplasts in BYDV-GAV-infected Zhong8601 leaf cells were fragmentized. Where thylakoids were not well developed, starch granules and plastoglobules were rare. Compared with mock-inoculated Zhong8601, chlorophyll content was markedly reduced, but the virus and H₂O₂ contents were significantly higher in BYDV-GAV-infected Zhong8601. The transcriptomic analyses revealed that chlorophyll biosynthesis and chloroplast related transcripts, encoding chlorophyll a/b binding protein, glucose-6-phosphate/phosphate translocator 2, and glutamyl-tRNA reductase 1, were down-regulated in BYDV-GAV-infected Zhong8601. Some phytohormone signaling-related transcripts, including abscisic acid (ABA) signaling factors (phospholipase D alpha 1 and calcineurin B-like protein 9) and nine ethylene response factors, were up-regulated. Additionally, reactive oxygen species (ROS)-related genes were transcriptionally regulated in BYDV-GAV infected Zhong8601, including three up-regulated transcripts encoding germin-like proteins (promoting ROS accumulation) and four down-regulated transcripts encoding peroxides (scavenging ROS). These results clearly suggest that the yellow dwarf symptom formation is mainly attributed to reduced chlorophyll content and fragmentized chloroplasts caused by down-regulation of the chlorophyll and chloroplast biosynthesis

  4. 7 CFR 319.37-2 - Prohibited articles.

    Science.gov (United States)

    2010-01-01

    ... Y (tobacco veinal necrosis strain); potato purple top wilt agent; potato marginal flavescence agent... mottle leaf virus, cocoa yellow mosaic virus, cocoa necrosis virus, Crinipellis perniciosa (Stahel... (vascular streak die-back), Xyleborus spp. beetles and Acrocercops cramella (Snellen) (cocoa moth...

  5. Structural Transitions and Energy Landscape for Cowpea Chlorotic Mottle Virus Capsid Mechanics from Nanomanipulation in Vitro and in Silico

    Science.gov (United States)

    Kononova, Olga; Snijder, Joost; Brasch, Melanie; Cornelissen, Jeroen; Dima, Ruxandra I.; Marx, Kenneth A.; Wuite, Gijs J. L.; Roos, Wouter H.; Barsegov, Valeri

    2013-10-01

    Physical properties of capsids of plant and animal viruses are important factors in capsid self-assembly, survival of viruses in the extracellular environment, and their cell infectivity. Virus shells can have applications as nanocontainers and delivery vehicles in biotechnology and medicine. Combined AFM experiments and computational modeling on sub-second timescales of the indentation nanomechanics of Cowpea Chlorotic Mottle Virus (CCMV) capsid show that the capsid's physical properties are dynamic and local characteristics of the structure, which depend on the magnitude and geometry of mechanical input. Surprisingly, under large deformations the CCMV capsid transitions to the collapsed state without substantial local structural alterations. The enthalpy change in this deformation state dH = 11.5 - 12.8 MJ/mol is mostly due to large-amplitude out-of-plane excitations, which contribute to the capsid bending, and the entropy change TdS = 5.1 - 5.8 MJ/mol is mostly due to coherent in-plane rearrangements of protein chains, which result in the capsid stiffening. Dynamic coupling of these modes defines the extent of elasticity and reversibility of capsid mechanical deformation. This emerging picture illuminates how unique physico-chemical properties of protein nanoshells help define their structure and morphology, and determine their viruses' biological function.

  6. First report of the complete sequence of Sida golden yellow vein virus from Jamaica.

    Science.gov (United States)

    Stewart, Cheryl S; Kon, Tatsuya; Gilbertson, Robert L; Roye, Marcia E

    2011-08-01

    Begomoviruses are phytopathogens that threaten food security [18]. Sida spp. are ubiquitous weed species found in Jamaica. Sida samples were collected island-wide, DNA was extracted via a modified Dellaporta method, and the viral genome was amplified using degenerate and sequence-specific primers [2, 11]. The amplicons were cloned and sequenced. Sequence analysis revealed that a DNA-A molecule isolated from a plant in Liguanea, St. Andrew, was 90.9% similar to Sida golden yellow vein virus-[United States of America:Homestead:A11], making it a strain of SiGYVV. It was named Sida golden yellow vein virus-[Jamaica:Liguanea 2:2008] (SiGYVV-[JM:Lig2:08]). The cognate DNA-B, previously unreported, was successfully cloned and was most similar to that of Malvastrum yellow mosaic Jamaica virus (MaYMJV). Phylogenetic analysis suggested that this virus was most closely related to begomoviruses that infect malvaceous hosts in Jamaica, Cuba and Florida in the United States.

  7. Case report: probable transmission of vaccine strain of yellow fever virus to an infant via breast milk

    OpenAIRE

    Kuhn, Susan; Twele-Montecinos, Loreto; MacDonald, Judy; Webster, Patricia; Law, Barbara

    2011-01-01

    The 17D yellow fever vaccine is a live-virus vaccine that has been in use since the 1940s. The incidence of encephalitis after yellow fever vaccination among young infants is much higher than among children older than nine months of age. Until recently, avoidance of vaccination by breastfeeding women who have received yellow fever vaccine had been based on theoretical grounds only. We report the probable transmission of vaccine strain of yellow fever virus from a mother to her infant through ...

  8. Genetic variation of eggplant mottled dwarf virus from annual and perennial plant hosts.

    Science.gov (United States)

    Pappi, Polyxeni G; Maliogka, Varvara I; Amoutzias, Gregory D; Katis, Nikolaos I

    2016-03-01

    The genetic diversity of eggplant mottled dwarf virus (EMDV), a member of the family Rhabdoviridae, was studied using isolates collected from different herbaceous and woody plant species and remote geographic areas. Sequences corresponding to the N, X, P, Y, M and G ORFs as well as the untranslated regions (UTRs) between ORFs were determined from all isolates. Low genetic diversity was found in almost all genomic regions studied except for the X ORF and the UTRs, which were more variable, while interestingly, an EMDV isolate from caper possessed a truncated G gene sequence. Furthermore, low d N /d S ratios, indicative of purifying selection, were calculated for all genes. Phylogenetic analysis showed that the EMDV isolates clustered in three distinct subgroups based on their geographical origin, with the exception of one subgroup that consisted of isolates from northern Greece and Cyprus. Overall, the level of genetic diversity of EMDV differed between seed- and asexually propagated plants in our collection, and this could be related to the mode of transmission.

  9. Evaluation of the suitability of a plant virus, pepper mild mottle virus, as a surrogate of human enteric viruses for assessment of the efficacy of coagulation-rapid sand filtration to remove those viruses.

    Science.gov (United States)

    Shirasaki, N; Matsushita, T; Matsui, Y; Yamashita, R

    2018-02-01

    Here, we evaluated the removal of three representative human enteric viruses - adenovirus (AdV) type 40, coxsackievirus (CV) B5, and hepatitis A virus (HAV) IB - and one surrogate of human caliciviruses - murine norovirus (MNV) type 1 - by coagulation-rapid sand filtration, using water samples from eight water sources for drinking water treatment plants in Japan. The removal ratios of a plant virus (pepper mild mottle virus; PMMoV) and two bacteriophages (MS2 and φX174) were compared with the removal ratios of human enteric viruses to assess the suitability of PMMoV, MS2, and φX174 as surrogates for human enteric viruses. The removal ratios of AdV, CV, HAV, and MNV, evaluated via the real-time polymerase chain reaction (PCR) method, were 0.8-2.5-log 10 when commercially available polyaluminum chloride (PACl, basicity 1.5) and virgin silica sand were used as the coagulant and filter medium, respectively. The type of coagulant affected the virus removal efficiency, but the age of silica sand used in the rapid sand filtration did not. Coagulation-rapid sand filtration with non-sulfated, high-basicity PACls (basicity 2.1 or 2.5) removed viruses more efficiently than the other aluminum-based coagulants. The removal ratios of MS2 were sometimes higher than those of the three human enteric viruses and MNV, whereas the removal ratios of φX174 tended to be smaller than those of the three human enteric viruses and MNV. In contrast, the removal ratios of PMMoV were similar to and strongly correlated with those of the three human enteric viruses and MNV. Thus, PMMoV appears to be a suitable surrogate for human enteric viruses for the assessment of the efficacy of coagulation-rapid sand filtration to remove viruses. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. Epidemiology of Cucurbit yellow stunting disorder virus in the US Southwest and development of virus resistant melon

    Science.gov (United States)

    Cucurbit yellow stunting disorder virus (CYSDV), emerged in the Southwest USA in 2006, where it is transmitted by the MEAM1 cryptic species of Bemisia tabaci. The virus results in late-season infection of spring melon crops with limited economic impact; however, all summer and fall cucurbits become ...

  11. High-level HIV-1 Nef transient expression in Nicotiana benthamiana using the P19 gene silencing suppressor protein of Artichoke Mottled Crinckle Virus

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    Bianco Linda

    2009-11-01

    Full Text Available Abstract Background In recent years, different HIV antigens have been successfully expressed in plants by either stable transformation or transient expression systems. Among HIV proteins, Nef is considered a promising target for the formulation of a multi-component vaccine due to its implication in the first steps of viral infection. Attempts to express Nef as a single protein product (not fused to a stabilizing protein in transgenic plants resulted in disappointingly low yields (about 0.5% of total soluble protein. In this work we describe a transient expression system based on co-agroinfiltration of plant virus gene silencing suppressor proteins in Nicotiana benthamiana, followed by a two-step affinity purification protocol of plant-derived Nef. Results The effect of three gene silencing viral suppressor proteins (P25 of Potato Virus X, P19 of either Artichoke Mottled Crinckle virus and Tomato Bushy Stunt virus on Nef transient expression yield was evaluated. The P19 protein of Artichoke Mottled Crinckle virus (AMCV-P19 gave the highest expression yield in vacuum co-agroinfiltration experiments reaching 1.3% of total soluble protein, a level almost three times higher than that previously reported in stable transgenic plants. The high yield observed in the co-agroinfiltrated plants was correlated to a remarkable decrease of Nef-specific small interfering RNAs (siRNAs indicating an effective modulation of RNA silencing mechanisms by AMCV-P19. Interestingly, we also showed that expression levels in top leaves of vacuum co-agroinfiltrated plants were noticeably reduced compared to bottom leaves. Moreover, purification of Nef from agroinfiltrated tissue was achieved by a two-step immobilized metal ion affinity chromatography protocol with yields of 250 ng/g of fresh tissue. Conclusion We demonstrated that expression level of HIV-1 Nef in plant can be improved using a transient expression system enhanced by the AMCV-P19 gene silencing suppressor

  12. Viruses affecting lentil (Lens culinaris Medik. in Greece; incidence and genetic variability of Bean leafroll virus and Pea enation mosaic virus

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    Elisavet K. CHATZIVASSILIOU

    2016-07-01

    Full Text Available In Greece, lentil (Lens culinaris Medik. crops are mainly established with non-certified seeds of local landraces, implying high risks for seed transmitted diseases. During April and May of the 2007–2012 growing seasons, surveys were conducted in eight regions of Greece (Attiki, Evros, Fthiotida, Korinthos, Kozani, Larissa, Lefkada and Viotia to monitor virus incidence in lentil fields. A total of 1216 lentil samples, from plants exhibiting symptoms suggestive of virus infection, were analyzed from 2007 to 2009, using tissue-blot immunoassays (TBIA. Pea seed-borne mosaic virus (PSbMV overall incidence was 4.9%, followed by Alfalfa mosaic virus (AMV (2.4% and Bean yellow mosaic virus (BYMV (1.0%. When 274 of the samples were tested for the presence of luteoviruses, 38.8% were infected with Bean leafroll virus (BLRV. Since BLRV was not identified in the majority of the samples collected from 2007 to 2009, representative symptomatic plants (360 samples were collected in further surveys performed from 2010 to 2012 and tested by ELISA. Two viruses prevailed in those samples: BLRV (36.1% was associated with stunting, yellowing, and reddening symptoms and Pea enation mosaic virus-1 (PEMV-1 (35.0% was associated with mosaic and mottling symptoms. PSbMV (2.2%, AMV (2.2%, BYMV (3.9% and CMV (2.8% were also detected. When the molecular variability was analyzed for representative isolates, collected from the main Greek lentil production areas, five BLRV isolates showed 95% identity for the coat protein (CP gene and 99% for the 3’ end region. Three Greek PEMV isolates co-clustered with an isolate from Germany when their CP sequence was compared with isolates with no mutation in the aphid transmission gene. Overall, limited genetic variability was detected among Greek isolates of BLRV and PEMV.

  13. Transgenic virus resistance in crop-wild Cucurbita pepo does not prevent vertical transmission of zucchini yellow mosaic virus

    Science.gov (United States)

    H. E. Simmons; Holly Prendeville; J. P. Dunham; M. J. Ferrari; J. D. Earnest; D. Pilson; G. P. Munkvold; E. C. Holmes; A. G. Stephenson

    2015-01-01

    Zucchini yellow mosaic virus (ZYMV) is an economically important pathogen of cucurbits that is transmitted both horizontally and vertically. Although ZYMV is seed-transmitted in Cucurbita pepo, the potential for seed transmission in virus-resistant transgenic cultivars is not known. We crossed and backcrossed a transgenic...

  14. The 96th Amino Acid of the Coat Protein of Cucumber Green Mottle Mosaic Virus Affects Virus Infectivity

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    Zhenwei Zhang

    2017-12-01

    Full Text Available Cucumber green mottle mosaic virus (CGMMV is one of the most devastating viruses infecting members of the family Cucurbitaceae. The assembly initiation site of CGMMV is located in the coding region of the coat protein, which is not only involved in virion assembly but is also a key factor determining the long-distance movement of the virus. To understand the effect of assembly initiation site and the adjacent region on CGMMV infectivity, we created a GTT deletion mutation in the GAGGTTG assembly initiation site of the infectious clone of CGMMV, which we termed V97 (deletion mutation at residue 97 of coat protein, followed by the construction of the V94A and T104A mutants. We observed that these three mutations caused mosaic after Agrobacterium-mediated transformation in Nicotiana benthamiana, albeit with a significant delay compared to the wild type clone. The mutants also had a common spontaneous E96K mutation in the coat protein. These results indicated that the initial assembly site and the sequence of the adjacent region affected the infectivity of the virus and that E96 might play an essential role in this process. We constructed two single point mutants—E96A and E96K—and three double mutants—V94A-E96K, V97-E96K and T104A-E96K—to further understand the role of E96 in CGMMV pathogenesis. After inoculation in N. benthamiana, E96A showed delayed systemic symptoms, but the E96K and three double mutants exhibited typical symptoms of mosaic at seven days post-infection. Then, sap from CGMMV-infected N. benthamiana leaves was mechanically inoculated on watermelon plants. We confirmed that E96 affected CGMMV infection using double antibody sandwich-enzyme-linked immunosorbent assay (DAS-ELISA, reverse transcription-polymerase chain reaction (RT-PCR, and sequencing, which further confirmed the successful infection of the related mutants, and that E96K can compensate the effect of the V94, V97, and T104 mutations on virus infectivity. In

  15. Survey of Viruses Affecting Legume Crops in the Amhara and Oromia Regions of Ethiopia

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    B. Bekele

    2005-12-01

    Full Text Available Field surveys were undertaken to identify the viral diseases affecting lentil, faba bean, chickpea, pea, fenugreek and grass pea in two regions of Ethiopia. The surveys were conducted in the regions of Amhara (Gonder and Gojam administrative zones and Oromia (Bale administrative zone during the 2003/2004 and 2004/2005 growing seasons, respectively. The survey covered 138 randomly selected fields (48 faba bean, 10 pea, 38 grass pea, 34 chickpea, 8 lentil in the Amhara region, and 51 legume fields (29 faba bean, 12 pea, 3 lentil, 5 fenugreek, 2 chickpea in the Oromia region. Virus disease incidence was determined by laboratory testing of 100–200 randomly-collected samples from each field against the antisera of 12 legume viruses. Of the 189 fields surveyed, 121 and 7 had, at the time of the survey, a virus disease incidence of 1% or less and more than 6%, respectively, based on visual inspection in the field; later laboratory testing showed that the number of fields in these two categories was in fact 99 and 56, respectively. Serological tests indicated that the most important viruses in the Amhara region were Faba bean necrotic yellows virus (FBNYV, Bean yellow mosaic virus (BYMV, Pea seed-borne mosaic virus (PSbMV and the luteoviruses [e.g. Beet western yellows virus (BWYV, Bean leaf roll virus (BLRV, Soybean dwarf virus (SbDV]. By contrast, only FBNYV and the luteoviruses were detected in the Oromia region. Other viruses, such as Broad bean mottle virus (BBMV and Alfalfa mosaic virus (AMV, were rarely detected in the Amhara region. This is the first report in Ethiopia of natural infection of faba bean, pea and fenugreek with SbDV, of fenugreek with BWYV, and of grass pea with BYMV, PSbMV and BWYV, and it is also the first recorded instance of BBMV infecting legume crops in Ethiopia.

  16. Pepo aphid-borne yellows virus: a new species in the genus Polerovirus.

    Science.gov (United States)

    Ibaba, Jacques D; Laing, Mark D; Gubba, Augustine

    2017-02-01

    Pepo aphid-borne yellows virus (PABYV) has been proposed as a putative representative of a new species in the genus Polerovirus in the family Luteoviridae. The genomes of two South African (SA) isolates of cucurbit-infecting PABYV were described in this record. Total RNA, extracted from a pattypan (Cucurbita pepo L.) and a baby marrow (C. pepo L.) leaf samples, was subjected to next-generation sequencing (NGS) on the HiSeq Illumina platform. Sanger sequencing was subsequently used to authenticate the integrity of PABYV's genome generated from de novo assembly of the NGS data. PABYV genome of SA isolates consists of 5813 nucleotides and displays an organisation typical of poleroviruses. Genome sequence comparisons of the SA PABYV isolates to other poleroviruses support the classification of PABYV as a new species in the genus Polerovirus. Recombination analyses showed that PABYV and Cucurbit aphid-borne yellows virus (CABYV) shared the same ancestor for the genome part situated between breaking points. Phylogenetic analyses of the RNA-dependent RNA polymerase and the coat protein genes showed that SA PABYV isolates shared distant relationship with CABYV and Suakwa aphid-borne yellows virus. Based on our results, we propose that PABYV is a distinct species in the genus Polerovirus.

  17. Lineage-Specific Real-Time RT-PCR for Yellow Fever Virus Outbreak Surveillance, Brazil.

    Science.gov (United States)

    Fischer, Carlo; Torres, Maria C; Patel, Pranav; Moreira-Soto, Andres; Gould, Ernest A; Charrel, Rémi N; de Lamballerie, Xavier; Nogueira, Rita Maria Ribeiro; Sequeira, Patricia C; Rodrigues, Cintia D S; Kümmerer, Beate M; Drosten, Christian; Landt, Olfert; Bispo de Filippis, Ana Maria; Drexler, Jan Felix

    2017-11-01

    The current yellow fever outbreak in Brazil prompted widespread yellow fever virus (YFV) vaccination campaigns, imposing a responsibility to distinguish between vaccine- and wild-type YFV-associated disease. We developed novel multiplex real-time reverse transcription PCRs that differentiate between vaccine and American wild-type YFV. We validated these highly specific and sensitive assays in an outbreak setting.

  18. Lineage-Specific Real-Time RT-PCR for Yellow Fever Virus Outbreak Surveillance, Brazil

    OpenAIRE

    Fischer, Carlo; Torres, Maria C.; Patel, Pranav; Moreira-Soto, Andres; Gould, Ernest A.; Charrel, Rémi N.; de Lamballerie, Xavier; Nogueira, Rita Maria Ribeiro; Sequeira, Patricia C.; Rodrigues, Cintia D.S.; Kümmerer, Beate M.; Drosten, Christian; Landt, Olfert; Bispo de Filippis, Ana Maria; Drexler, Jan Felix

    2017-01-01

    The current yellow fever outbreak in Brazil prompted widespread yellow fever virus (YFV) vaccination campaigns, imposing a responsibility to distinguish between vaccine- and wild-type YFV-associated disease. We developed novel multiplex real-time reverse transcription PCRs that differentiate between vaccine and American wild-type YFV. We validated these highly specific and sensitive assays in an outbreak setting.

  19. Occurrence of Pepper Mild Mottle Virus (PMMoV) in Groundwater from a Karst Aquifer System in the Yucatan Peninsula, Mexico.

    Science.gov (United States)

    Rosiles-González, Gabriela; Ávila-Torres, Gerardo; Moreno-Valenzuela, Oscar A; Acosta-González, Gilberto; Leal-Bautista, Rosa María; Grimaldo-Hernández, Cinthya D; Brown, Judith K; Chaidez-Quiroz, Cristóbal; Betancourt, Walter Q; Gerba, Charles P; Hernández-Zepeda, Cecilia

    2017-12-01

    The Yucatan Peninsula of Mexico hosts a karst aquifer system that is the only source of freshwater for the area; however, it is vulnerable to human-mediated contamination. Pepper mild mottle virus (PMMoV) is one of the most abundant RNA viruses associated with human feces, making it a viable indicator for tracking fecal pollution in aquatic environments, including groundwater. In this study, groundwater samples collected from a karst aquifer from fresh and brackish water locations were analyzed for fecal indicator bacteria, somatic and male F+ specific coliphages, and PMMoV during the rainy and dry seasons. Total coliform bacteria were detected at all sites, whereas Escherichia coli were found at relatively low levels water type (p > 0.05). Physicochemical and indicator bacteria were not correlated with PMMoV concentrations. The abundance and prevalence of PMMoV in the karst aquifer may reflect its environmental persistence and its potential as a fecal indicator in this karst aquifer system.

  20. Investigations into yellow fever virus and other arboviruses in the northern regions of Kenya.

    Science.gov (United States)

    Henderson, B E; Metselaar, D; Kirya, G B; Timms, G L

    1970-01-01

    Previous studies having shown an appreciable level of yellow fever immunity to exist in northern Kenya, further epidemiological and serological surveys were carried out there in 1968 in an attempt to define more clearly the distribution of yellow fever and to locate possible vector and reservoir hosts of the disease; these surveys also provided information on a number of other arboviruses.Altogether 436 sera from 5 areas in northern Kenya were screened by haemagglutination-inhibition tests with 8 antigens, and 107 of these sera by neutralization tests for Group-B arboviruses. Small numbers of yellow-fever-immune adults were found in Ileret, Garissa, Loglogo and Mikona. At Marsabit high proportions of immune adults and children were found among the Burgi tribe. As the Burgi are permanent agricultural workers on Marsabit Mountain, an entomological investigation was made, over 15 000 mosquitos being collected. From these, 13 strains of Pongola virus, 1 strain of Semliki Forest virus and an unidentified virus were isolated, but no yellow fever strains. Aedes africanus and Aedes simpsoni were not found at Marsabit; small numbers of Aedes aegypti were collected biting man. The vector potential of other mosquitos collected (particularly Mansonia africana, which is present throughout the year) is discussed.

  1. 78 FR 24471 - Endangered and Threatened Wildlife and Plants; Endangered Status for the Sierra Nevada Yellow...

    Science.gov (United States)

    2013-04-25

    ... patterned with dark spots (Jennings and Hayes 1994, p. 74; Stebbins 2003, p. 233). These spots may be large...). Mountain yellow-legged frogs have smoother skin, generally with heavier spotting and mottling dorsally...

  2. Serological reactions in Rhesus monkeys inoculated with the 17D strain of yellow fever virus.

    Science.gov (United States)

    GROOT, H

    1962-01-01

    Haemagglutination-inhibition tests, which depend on the appearance of haemagglutination-inhibiting antibodies in the serum in virus infections, are in common use in the study of arthropod-borne diseases. This paper contains the results of an investigation into the appearance and pattern of haemagglutination-inhibiting antibodies in the serum of rhesus monkeys inoculated intracerebrally with the 17D strain of yellow fever virus during the testing of seed lots of yellow fever vaccine. These antibodies appeared on the tenth day after inoculation, and were still demonstrable four years later. In all of the eight monkeys tested complement-fixing and neutralizing antibodies against yellow fever antigens also developed, and in six out of the eight heterologous antigens developed.

  3. Molecular characterization and experimental host range of an isolate of Wissadula golden mosaic St. Thomas virus.

    Science.gov (United States)

    Collins, A M; Mujaddad-ur-Rehman, Malik; Brown, J K; Reddy, C; Wang, A; Fondong, V; Roye, M E

    2009-12-01

    Partial genome segments of a begomovirus were previously amplified from Wissadula amplissima exhibiting yellow-mosaic and leaf-curl symptoms in the parish of St. Thomas, Jamaica and this isolate assigned to a tentative begomovirus species, Wissadula golden mosaic St. Thomas virus. To clone the complete genome of this isolate of Wissadula golden mosaic St. Thomas virus, abutting primers were designed to PCR amplify its full-length DNA-A and DNA-B components. Sequence analysis of the complete begomovirus genome obtained, confirmed that it belongs to a distinct begomovirus species and this isolate was named Wissadula golden mosaic St. Thomas virus-[Jamaica:Albion:2005] (WGMSTV-[JM:Alb:05]). The genome of WGMSTV-[JM:Alb:05] is organized similar to that of other bipartite Western Hemisphere begomoviruses. Phylogenetic analyses placed the genome components of WGMSTV-[JM:Alb:05] in the Abutilon mosaic virus clade and showed that the DNA-A component is most closely related to four begomovirus species from Cuba, Tobacco leaf curl Cuba virus, Tobacco leaf rugose virus, Tobacco mottle leaf curl virus, and Tomato yellow distortion leaf virus. The putative Rep-binding-site motif in the common region of WGMSTV-[JM:Alb:05] was observed to be identical to that of Chino del tomate virus-Tomato [Mexico:Sinaloa:1983], Sida yellow mosaic Yucatan virus-[Mexico:Yucatan:2005], and Tomato leaf curl Sinaloa virus-[Nicaragua:Santa Lucia], suggesting that WGMSTV-[JM:Alb:05] is capable of forming viable pseudo-recombinants with these begomoviruses, but not with other members of the Abutilon mosaic virus clade. Biolistic inoculation of test plant species with partial dimers of the WGMSTV-[JM:Alb:05] DNA-A and DNA-B components showed that the virus was infectious to Nicotiana benthamiana and W. amplissima and the cultivated species Phaseolus vulgaris (kidney bean) and Lycopersicon esculentum (tomato). Infected W. amplissima plants developed symptoms similar to symptoms observed under field

  4. Analysis of the solvent accessibility of cysteine residues on Maize rayado fino virus virus-like particles produced in Nicotiana benthamiana plants and cross-linking of peptides to VLPs.

    Science.gov (United States)

    Natilla, Angela; Hammond, Rosemarie W

    2013-02-14

    displayed on the surface of plant viruses such as, Brome mosaic virus, Carnation mottle virus, Cowpea chlorotic mottle virus, Tobacco mosaic virus, Turnip yellow mosaic virus, and MRFV.

  5. Identifikasi Pepper vein yellows virus yang Berasosiasi dengan Penyakit Yellow Vein Banding pada Tanaman Mentimun di Bali

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    I Dewa Nyoman Nyana

    2016-11-01

    Full Text Available Yellowing vein banding disease has been reported infecting cucurbit plants in Bali since 2014. Similar vein banding symptom on chilli pepper was observed previously, and early diagnosis indicated infection of Polerovirus. The objective of this research was to confirm the presence of Polerovirus infection on cucumber plant showing yellow vein banding symptom in Bali. Reverse transcription polymerase chain reaction – based detection method was conducted using specific primer pairs PeVYV-CP-F-BamH1/ PeVYV-CP-R-Pst1followed by sequencing and nucleotide sequence analysis.  Specific DNA fragments of ± 650 bp was successfully amplified from field samples.  Nucleotide sequence analysis showed that the sequence has the highest similarity > 95% with Pepper vein yellow virus (PeVYV infecting chili pepper from Indonesia (Bali, and Rembang, Japan, and Greece.

  6. Screening test for neutralizing antibodies against yellow fever virus, based on a flavivirus pseudotype.

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    Séverine Mercier-Delarue

    Full Text Available Given the possibility of yellow fever virus reintroduction in epidemiologically receptive geographic areas, the risk of vaccine supply disruption is a serious issue. New strategies to reduce the doses of injected vaccines should be evaluated very carefully in terms of immunogenicity. The plaque reduction test for the determination of neutralizing antibodies (PRNT is particularly time-consuming and requires the use of a confinement laboratory. We have developed a new test based on the use of a non-infectious pseudovirus (WN/YF17D. The presence of a reporter gene allows sensitive determination of neutralizing antibodies by flow cytometry. This WN/YF17D test was as sensitive as PRNT for the follow-up of yellow fever vaccinees. Both tests lacked specificity with sera from patients hospitalized for acute Dengue virus infection. Conversely, both assays were strictly negative in adults never exposed to flavivirus infection or vaccination, and in patients sampled some time after acute Dengue infection. This WN/YF17D test will be particularly useful for large epidemiological studies and for screening for neutralizing antibodies against yellow fever virus.

  7. Survey on The Occurrence of Viruses Infecting Cucurbits in Yogyakarta and Central Java

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    Budi Setiadi Daryono

    2009-12-01

    Full Text Available Cucurbits are grown throughout the Java Island as dry season crops. Plants having mosaic, mottling, chlorosis and leaf distortion symptoms were frequently found in most of the cucurbit fields during the survey which conducted in Central Java including Sleman, Kulon Progo, and Klaten during July–September 2000 and 2001. Using double antibody sandwich enzyme-linked immunosorbent assay (DAS-ELISA; Cucumber mosaic virus (CMV, Cucumber green mottle mosaic virus (CGMMV and Kyuri green mottle mosaic virus (KGMMV were found infecting cucurbits. CMV was widespread, infecting 48.9% of the samples tested followed by CGMMV (12.8% and KGMMV (6.4%, while others samples (31.9% were not tested, double infections were common with 8.5 % of the samples being infected with two viruses (CGMMV and KGMMV and 34% with three viruses (CMV, CGMMV, and KGMMV. Severe mosaic and mottle symptoms were associated most often with single infection of CGMMV and KGMMV respectively. In addition, these are the first detections of CGMMV and KGMMV infecting cucurbit plants in Indonesia. Tanaman labu-labuan umumnya tumbuh sepanjang musim kemarau diPulau Jawa. Tanaman labu-labuan dengan gejala mosaik, klorosis, mottling dan bentuk daun serta buah yang berubah banyak dijumpai selama survei yang dilakukan di Kulon Progo, Sleman dan Klaten pada bulan Juli sampai September tahun 2000 dan 2001. Deteksi menggunakan metode double antibody sandwich enzyme-linked immunosorbent assay (DAS-ELISA telah berhasil mengetahui keberadaan dan infeksiCucumber mosaic virus(CMV,Cucumber green mottle mosaic virus (CGMMV dan Kyuri green mottle mosaic virus (KGMMV pada tanaman labu-labuan di tiga kabupaten tersebut. CMV menginfeksi tanaman labu-labuan tinggi yaitu 48,9% dari jumlah sampel tanaman yang dikoleksi, kemudian CGMMV (12,8% dan KGMMV(6,4%, sedangkan sebanyak 14 sampel tanaman (31,9%tidak dideteksi.Infeksi ganda banyak ditemukan dan 8,5 % sampel tanaman terinfeksi oleh dua jenis virus (CGMMV dan

  8. A flow cytometry-based assay for quantifying non-plaque forming strains of yellow fever virus.

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    Erika Hammarlund

    Full Text Available Primary clinical isolates of yellow fever virus can be difficult to quantitate by standard in vitro methods because they may not form discernable plaques or induce a measurable cytopathic effect (CPE on cell monolayers. In our hands, the Dakar strain of yellow fever virus (YFV-Dakar could not be measured by plaque assay (PA, focus-forming assay (FFA, or by measurement of CPE. For these reasons, we developed a YFV-specific monoclonal antibody (3A8.B6 and used it to optimize a highly sensitive flow cytometry-based tissue culture limiting dilution assay (TC-LDA to measure levels of infectious virus. The TC-LDA was performed by incubating serial dilutions of virus in replicate wells of C6/36 cells and stained intracellularly for virus with MAb 3A8.B6. Using this approach, we could reproducibly quantitate YFV-Dakar in tissue culture supernatants as well as from the serum of viremic rhesus macaques experimentally infected with YFV-Dakar. Moreover, the TC-LDA approach was >10-fold more sensitive than standard plaque assay for quantitating typical plaque-forming strains of YFV including YFV-17D and YFV-FNV (French neurotropic vaccine. Together, these results indicate that the TC-LDA technique is effective for quantitating both plaque-forming and non-plaque-forming strains of yellow fever virus, and this methodology may be readily adapted for the study and quantitation of other non-plaque-forming viruses.

  9. 40 CFR 174.514 - Coat Protein of Watermelon Mosaic Virus-2 and Zucchini Yellow Mosaic Virus; exemption from the...

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Coat Protein of Watermelon Mosaic Virus-2 and Zucchini Yellow Mosaic Virus; exemption from the requirement for a tolerance. 174.514 Section 174.514 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS PROCEDURES AND REQUIREMENTS FOR PLANT-INCORPORATED...

  10. Genesis of a mottled horizon by Fe-depletion within a laterite cover in the Amazon Basin.

    OpenAIRE

    Rosolen , Vania; Lamotte , Mathieu; Boulet , René; Trichet , Jean; Rouer , Olivier; José Melfi , Adolpho

    2002-01-01

    A mottled horizon in a laterite cover (without any duricrust) was studied by microscopy and quantitative chemical microanalysis. Apart from the voids, light red spots consisting of Fe-rich particles (≈2 μm) are set in clayey plasma. Dark red spots consisted of concentrations of Fe-rich particles. These patterns are inherited. On the border of structural or biological voids, where Fe-depletion features are systematic, gray or yellow spots result from dissolution of the Fe-rich particles and im...

  11. Monoclonal antibody-based serological methods for detection of Cucumber green mottle mosaic virus

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    Qian Yajuan

    2011-05-01

    Full Text Available Abstract Background Cucumber green mottle mosaic virus (CGMMV, a member of the genus Tobamovirus, can be transmitted by seeds and infects many cucurbit species, causing serious yield losses in cucumber and watermelon plants. In this paper, five serological methods including antigen-coated plate enzyme-linked immunosorbent assay (ACP-ELISA, triple antibody sandwich enzyme-linked immunosorbent assay (TAS-ELISA, Dot-immunobinding assay (DBIA, direct tissue blot immunoassay (DTBIA and immunocapture reverse transcriptase polymerase chain reaction (IC-RT-PCR were described for detection and diagnosis of CGMMV. Results Using the purified CGMMV particles as immunogens, six murine monoclonal antibodies (MAbs were produced. Five serological methods were established using the MAb 4H1 and detection sensitivity was compared using purified preparations and infected-plant tissue extracts. The detection sensitivity of ACP-ELISA was 0.16 ng of purified CGMMV, whereas TAS-ELISA was more sensitive than ACP-ELISA with a minimum detection of 0.04 ng of purified CGMMV. The sensitivities of TAS-ELISA and DBIA were similar for detecting CGMMV in infected-plant tissue extracts, and were four times higher than ACP-ELISA. The IC-RT-PCR was the most sensitive method, which could detect as little as 0.1 pg of purified virus. The detection sensitivity of IC-RT-PCR for CGMMV-infected plant tissues was about 400 times higher than that of TAS-ELISA and DBIA. Conclusions The established ACP-ELISA, TAS-ELISA, DBIA and DTBIA are suitable for routine CGMMV detection of large-scale samples in the field survey, while IC-RT-PCR is more sensitive and suitable for acquiring information about the viral genome.

  12. What Does the Future Hold for Yellow Fever Virus? (I

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    Raphaëlle Klitting

    2018-06-01

    Full Text Available The recent resurgence of yellow fever virus (YFV activity in the tropical regions of Africa and South America has sparked renewed interest in this infamous arboviral disease. Yellow fever virus had been a human plague for centuries prior to the identification of its urban transmission vector, the Aedes (Stegomyia aegypti (Linnaeus mosquito species, and the development of an efficient live-attenuated vaccine, the YF-17D strain. The combination of vector-control measures and vaccination campaigns drastically reduced YFV incidence in humans on many occasions, but the virus never ceased to circulate in the forest, through its sylvatic invertebrate vector(s and vertebrate host(s. Outbreaks recently reported in Central Africa (2015–2016 and Brazil (since late 2016, reached considerable proportions in terms of spatial distribution and total numbers of cases, with multiple exports, including to China. In turn, questions about the likeliness of occurrence of large urban YFV outbreaks in the Americas or of a successful import of YFV to Asia are currently resurfacing. This two-part review describes the current state of knowledge and gaps regarding the molecular biology and transmission dynamics of YFV, along with an overview of the tools that can be used to manage the disease at individual, local and global levels.

  13. First Complete Genome Sequence of Suakwa aphid-borne yellows virus from East Timor

    Science.gov (United States)

    Maina, Solomon; Edwards, Owain R.; de Almeida, Luis; Ximenes, Abel

    2016-01-01

    We present here the first complete genomic RNA sequence of the polerovirus Suakwa aphid-borne yellows virus (SABYV), from East Timor. The isolate sequenced came from a virus-infected pumpkin plant. The East Timorese genome had a nucleotide identity of 86.5% with the only other SABYV genome available, which is from Taiwan. PMID:27469955

  14. Transcriptome analysis of watermelon (Citrullus lanatus) fruits in response to Cucumber green mottle mosaic virus (CGMMV) infection.

    Science.gov (United States)

    Li, Xiaodong; An, Mengnan; Xia, Zihao; Bai, Xiaojiao; Wu, Yuanhua

    2017-12-01

    Cucumber green mottle mosaic virus (CGMMV) belongs to the Tobamovirus genus and is a major global plant virus on cucurbit plants. It causes severe disease symptoms on infected watermelon plants (Citrullus lanatus), particularly inducing fruit decay. However, little is known about the molecular mechanism of CGMMV-induced watermelon fruit decay. For this study, comparative analysis of transcriptome profiles of CGMMV-inoculated and mock-inoculated watermelon fruits were conducted via RNA-Seq. A total of 1,621 differently expressed genes (DEGs) were identified in CGMMV-inoculated watermelon, among which 1,052 were up-regulated and 569 were down-regulated. Functional annotation analysis showed that several DEGs were involved in carbohydrate metabolism, hormone biosynthesis and signaling transduction, secondary metabolites biosynthesis, and plant-pathogen interactions. We furthermore found that some DEGs were related to cell wall components and photosynthesis, which may directly be involve in the development of the symptoms associated with diseased watermelons. To confirm the RNA-Seq data, 15 DEGs were selected for gene expression analysis by qRT-PCR. The results showed a strong correlation between these two sets of data. Our study identified many candidate genes for further functional studies during CGMMV-watermelon interactions, and will furthermore help to clarify the understanding of pathogenic mechanism underlying CGMMV infection in cucurbit plants.

  15. Yellow fever virus: genetic and phenotypic diversity and implications for detection, prevention and therapy.

    Science.gov (United States)

    Beasley, David W C; McAuley, Alexander J; Bente, Dennis A

    2015-03-01

    Yellow fever virus (YFV) is the prototypical hemorrhagic fever virus, yet our understanding of its phenotypic diversity and any molecular basis for observed differences in disease severity and epidemiology is lacking, when compared to other arthropod-borne and haemorrhagic fever viruses. This is, in part, due to the availability of safe and effective vaccines resulting in basic YFV research taking a back seat to those viruses for which no effective vaccine occurs. However, regular outbreaks occur in endemic areas, and the spread of the virus to new, previously unaffected, areas is possible. Analysis of isolates from endemic areas reveals a strong geographic association for major genotypes, and recent epidemics have demonstrated the emergence of novel sequence variants. This review aims to outline the current understanding of YFV genetic and phenotypic diversity and its sources, as well as the available animal models for characterizing these differences in vivo. The consequences of genetic diversity for detection and diagnosis of yellow fever and development of new vaccines and therapeutics are discussed. Copyright © 2015 Elsevier B.V. All rights reserved.

  16. Prospecting sugarcane resistance to Sugarcane yellow leaf virus by genome-wide association.

    Science.gov (United States)

    Debibakas, S; Rocher, S; Garsmeur, O; Toubi, L; Roques, D; D'Hont, A; Hoarau, J-Y; Daugrois, J H

    2014-08-01

    Using GWAS approaches, we detected independent resistant markers in sugarcane towards a vectored virus disease. Based on comparative genomics, several candidate genes potentially involved in virus/aphid/plant interactions were pinpointed. Yellow leaf of sugarcane is an emerging viral disease whose causal agent is a Polerovirus, the Sugarcane yellow leaf virus (SCYLV) transmitted by aphids. To identify quantitative trait loci controlling resistance to yellow leaf which are of direct relevance for breeding, we undertook a genome-wide association study (GWAS) on a sugarcane cultivar panel (n = 189) representative of current breeding germplasm. This panel was fingerprinted with 3,949 polymorphic markers (DArT and AFLP). The panel was phenotyped for SCYLV infection in leaves and stalks in two trials for two crop cycles, under natural disease pressure prevalent in Guadeloupe. Mixed linear models including co-factors representing population structure fixed effects and pairwise kinship random effects provided an efficient control of the risk of inflated type-I error at a genome-wide level. Six independent markers were significantly detected in association with SCYLV resistance phenotype. These markers explained individually between 9 and 14 % of the disease variation of the cultivar panel. Their frequency in the panel was relatively low (8-20 %). Among them, two markers were detected repeatedly across the GWAS exercises based on the different disease resistance parameters. These two markers could be blasted on Sorghum bicolor genome and candidate genes potentially involved in plant-aphid or plant-virus interactions were localized in the vicinity of sorghum homologs of sugarcane markers. Our results illustrate the potential of GWAS approaches to prospect among sugarcane germplasm for accessions likely bearing resistance alleles of significant effect useful in breeding programs.

  17. First report of Squash vein yellowing virus in watermelon in Guatemala

    Science.gov (United States)

    In this study, we report the first detection of Squash vein yellowing virus (SqVYV)-induced watermelon vine decline in Central America. Symptoms including wilt and collapse of plants at harvest, and non-marketable fruits with internal rind necrosis were observed. This report provides an overview o...

  18. The 3.2 Angstrom Resolution Structure of the Polymorphic Cowpea Chlorotic Mottle Virus Ribonucleoprotein Particle

    Science.gov (United States)

    Speir, Jeffrey Alan

    Structural studies of the polymorphic cowpea chlorotic mottle virus have resulted in high resolution structures for two distinct icosahedral ribonucleoprotein particle conformations dependent upon whether acidic or basic pH conditions prevail. CCMV is stable below pH 6.5, however metal-free particles maintain a 10% increase in hydrodynamic volume at pH >=q 7.5. Identification of this swollen' form of CCMV, which can easily be disrupted with 1M NaCl, led to the first reassembly of an icosahedral virus in vitro from purified viral protein and RNA to form infectious particles, and its assembly has been the subject of biochemical and biophysical investigations for over twenty-five years. Under well defined conditions of pH, ionic strength and divalent metal ion concentration, CCMV capsid protein or capsid protein and RNA will reassemble to form icosahedral particles of various sizes, sheets, tubes, rosettes, and a variety of laminar structures which resemble virion structures from non-related virus families. Analysis of native particles at 3.2A resolution and swollen particles at 28A resolution has suggested that the chemical basis for the formation of polymorphic icosahedral and anisometric structures is: (i) hexamers formed of beta-barrel subunits stabilized by an unusual hexameric parallel beta structure made up of their N-termini, (ii) the location of protein-RNA interactions, (iii) divalent metal cation binding sites that regulate quasi-symmetrical subunit associations, (iv) charge repulsion across the same interfaces when lacking divalent metal ions at basic pH, which induces the formation of sixty 20A diameter portals for RNA release, and (v) a novel, C-terminal-based, subunit dimer assembly unit. The use of C- and N-terminal arms in CCMV has not been observed in other icosahedral RNA virus structures determined at near atomic resolution, however, their detailed interactions and roles in stabilizing the quaternary organization of CCMV are related to that found

  19. USVL-380, A zucchini yellow mosaic virus resistant watermelon breeding line

    Science.gov (United States)

    We report the development of a novel watermelon line ‘USVL-380’ [Citrullus lanatus (Thunb.) Matsum. & Nakai] resistant to the zucchini yellow mosaic virus-Florida strain (ZYMV-FL). This breeding line is homozygous for the recessive eukaryotic elongation factor eIF4E allele associated with ZYMV-resis...

  20. Beet western yellows virus infects the carnivorous plant Nepenthes mirabilis.

    Science.gov (United States)

    Miguel, Sissi; Biteau, Flore; Mignard, Benoit; Marais, Armelle; Candresse, Thierry; Theil, Sébastien; Bourgaud, Frédéric; Hehn, Alain

    2016-08-01

    Although poleroviruses are known to infect a broad range of higher plants, carnivorous plants have not yet been reported as hosts. Here, we describe the first polerovirus naturally infecting the pitcher plant Nepenthes mirabilis. The virus was identified through bioinformatic analysis of NGS transcriptome data. The complete viral genome sequence was assembled from overlapping PCR fragments and shown to share 91.1 % nucleotide sequence identity with the US isolate of beet western yellows virus (BWYV). Further analysis of other N. mirabilis plants revealed the presence of additional BWYV isolates differing by several insertion/deletion mutations in ORF5.

  1. Evaluation des variétés de riz prometteuses pour la résistance à ...

    African Journals Online (AJOL)

    , (Rice yellow Mottle Virus ou RYMV), l'helminthosporiose (Helminthosporium oryzae ou Bipolaris oryzae) et la cécidomyie africaine des galles de riz (Orseolia oryzivora) sont les principales contraintes biotiques majeures qui causent plus de ...

  2. Genome-wide association mapping of barley yellow dwarf virus tolerance in spring oat (Avena sativa L.)

    Science.gov (United States)

    Barley yellow dwarf (BYD) is one of the most destructive diseases of cereal crops worldwide. Barley yellow dwarf viruses (BYDVs) are responsible for BYD and affect many cereals including oat (Avena sativa L.). Until recently, the molecular marker technology in oat has not allowed for many marker-t...

  3. Association of VPg and eIF4E in the host tropism at the cellular level of Barley yellow mosaic virus and Wheat yellow mosaic virus in the genus Bymovirus.

    Science.gov (United States)

    Li, Huangai; Shirako, Yukio

    2015-02-01

    Barley yellow mosaic virus (BaYMV) and Wheat yellow mosaic virus (WYMV) are separate species in the genus Bymovirus with bipartite plus-sense RNA genomes. In fields, BaYMV infects only barley and WYMV infects only wheat. Here, we studied the replicative capability of the two viruses in barley and wheat mesophyll protoplasts. BaYMV replicated in both barley and wheat protoplasts, but WYMV replicated only in wheat protoplasts. The expression of wheat translation initiation factor 4E (eIF4E), a common host factor for potyviruses, from the WYMV genome enabled WYMV replication in barley protoplasts. Replacing the BaYMV VPg gene with that of WYMV abolished BaYMV replication in barley protoplasts, whereas the additional expression of wheat eIF4E from BaYMV genome restored the replication of the BaYMV mutant in barley protoplasts. These results indicate that both VPg and the host eIF4E are involved in the host tropism of BaYMV and WYMV at the replication level. Copyright © 2014 Elsevier Inc. All rights reserved.

  4. Bunias orientalis L. as a natural overwintering host OF Turnip mosaic virus

    Directory of Open Access Journals (Sweden)

    Tadeusz Kobyłko

    2012-12-01

    Full Text Available A virus was isolated, using mechanical inoculation, from hill mustard (Bunias orientalis L. plants exhibiting yellow mottling and blistering on leaves, which were frequently accompanied by asymmetric leaf narrowing. It systemically infected certain plants from the family Brassicaceae (Brassica rapa, Bunias orientalis, Hesperis matronalis, Sinapis alba as well as Cleome spinosa and Nicotiana clevelandii, and locally Atriplex hortensis, Chenopodium quinoa, Ch. amaranticolor, N. tabacum. In the sap, it maintained infectivity for 3-4 days and lost it after heating for 10 min. at a temperature of 55 - 60oC or when diluted with water at 10-3. Virus particles were thread- like with a length of 675 - 710 nm. Based on an analysis of biological properties of the pathogen, serological response, particle morphology and data from field observations, it was identified as an isolate of Turnip mosaic virus (TuMV, and hill mustard was recognised as a natural overwintering host for this pathogen.

  5. In vitro transcription of Sonchus yellow net virus RNA by a virus-associated RNA-dependent RNA polymerase

    NARCIS (Netherlands)

    Flore, P.H.

    1986-01-01

    The aim of the investigation presented in this thesis was to elucidate the nature of the RNA- dependent RNA polymerase, thought to be associated with Sonchus yellow net virus (SYNV), a rhabdovirus infecting plants. This research was initiated to shed light on the

  6. Natural co-infection of Solanum tuberosum crops by the Potato yellow vein virus and potyvirus in Colombia

    Directory of Open Access Journals (Sweden)

    Angela Villamil-Garzón

    2014-08-01

    Full Text Available The Potato yellow vein virus (PYVV, a Crinivirus with an RNA tripartite genome, is the causal agent of the potato yellow vein disease, reported in Colombian since 1950, with yield reductions of up to 50%. Co-infection of two or more viruses is common in nature and can be associated with differences in virus accumulation and symptom expression. No evidence of mixed infection between PYVV and other viruses has been reported. In this study, eight plants showing yellowing PYVV symptoms: four Solanum tuberosum Group Phureja (P and four Group Andigena (A, were collected in Cundinamarca, Colombia to detect mixed infection in the isolates using next generation sequencing (NGS. The Potato virus Y (PVY complete genome (similar to N strain and the Potato virus V (PVV partial genomes were detected using NGS and re-confirmed by RT-PCR. Preliminary field screening in a large sample showed that PYVV and PVY co-infect potato plants with a prevalence of 21% within the P group and 23% within the A group. This is the first report of co-infection of PYVV and potyvirus in Colombia and with the use of NGS. Considering that potyviruses enhance symptom severity and/or yield reductions in mixed infections, our results may be relevant for disease diagnosis, breeding programs and tuber certification.

  7. Detection of beet necrotic yellow vein virus in Pakistan using bait ...

    African Journals Online (AJOL)

    The Northwestern plains of Pakistan are the major sugar beet producing region in the country, providing an important alternative to sugar cane for sugar production when sugar cane is absent in the fields. We surveyed this region for four consecutive years and found that Beet necrotic yellow vein virus (BNYVV) is prevalent ...

  8. First Complete Genome Sequence of Pepper vein yellows virus from Australia

    Science.gov (United States)

    Maina, Solomon; Edwards, Owain R.

    2016-01-01

    We present here the first complete genomic RNA sequence of the polerovirus Pepper vein yellows virus (PeVYV) obtained from a pepper plant in Australia. We compare it with complete PeVYV genomes from Japan and China. The Australian genome was more closely related to the Japanese than the Chinese genome. PMID:27231375

  9. The phylogeny of yellow fever virus 17D vaccines.

    Science.gov (United States)

    Stock, Nina K; Boschetti, Nicola; Herzog, Christian; Appelhans, Marc S; Niedrig, Matthias

    2012-02-01

    In recent years the safety of the yellow fever live vaccine 17D came under scrutiny. The focus was on serious adverse events after vaccinations that resemble a wild type infection with yellow fever and whose reasons are still not known. Also the exact mechanism of attenuation of the vaccine remains unknown to this day. In this context, the standards of safety and surveillance in vaccine production and administration have been discussed. Therein embodied was the demand for improved documentation of the derivation of the seed virus used for yellow fever vaccine production. So far, there was just a historical genealogy available that is based on source area and passage level. However, there is a need for a documentation based on molecular information to get better insights into the mechanisms of pathology. In this work we sequenced the whole genome of different passages of the YFV-17D strain used by Crucell Switzerland AG for vaccine production. Using all other publically available 17D full genome sequences we compared the sequence variance of all vaccine strains and oppose a phylogenetic tree based on full genome sequences to the historical genealogy. Copyright © 2011 Elsevier Ltd. All rights reserved.

  10. Beet yellow stunt virus in cells of Sonchus oleraceus L. and its relation to host mitochondria.

    Science.gov (United States)

    Esau, K

    1979-10-15

    In Sonchus oleraceus L. (Asteraceae) infected with the beet yellow stunt virus (BYSV) the virions are found in phloem cells, including the sieve elements. In parenchymatous phloem cells, the virus is present mainly in the cytoplasm. In some parenchymatous cells, containing massive accumulations of virus, the flexuous rodlike virus particles are found partly inserted into mitochondrial cristae. The mitochondrial envelope is absent where virus is present in the cristae. A similar relation between virus and host mitochondria apparently has not been recorded for any other plant virus.

  11. Construction and characterization of a recombinant yellow fever virus stably expressing Gaussia luciferase

    Directory of Open Access Journals (Sweden)

    TELISSA C. KASSAR

    Full Text Available ABSTRACT Yellow fever is an arthropod-borne viral disease that still poses high public health concerns, despite the availability of an effective vaccine. The development of recombinant viruses is of utmost importance for several types of studies, such as those aimed to dissect virus-host interactions and to search for novel antiviral strategies. Moreover, recombinant viruses expressing reporter genes may greatly facilitate these studies. Here, we report the construction of a recombinant yellow fever virus (YFV expressing Gaussia luciferase (GLuc (YFV-GLuc. We show, through RT-PCR, sequencing and measurement of GLuc activity, that stability of the heterologous gene was maintained after six passages. Furthermore, a direct association between GLuc expression and viral replication was observed (r2=0.9967, indicating that measurement of GLuc activity may be used to assess viral replication in different applications. In addition, we evaluated the use of the recombinant virus in an antiviral assay with recombinant human alfa-2b interferon. A 60% inhibition of GLuc expression was observed in cells infected with YFV-GLuc and incubated with IFN alfa-2b. Previously tested on YFV inhibition by plaque assays indicated a similar fold-decrease in viral replication. These results are valuable as they show the stability of YFV-GLuc and one of several possible applications of this construct.

  12. The Significance of Wild Plants in the Evolutionary Ecology of Three Major Viruses Infecting Cultivated Sweetpotato in Uganda

    OpenAIRE

    Tugume Kajungu, Arthur

    2010-01-01

    The studies presented in this thesis contribute to the understanding of evolutionary ecology of three major viruses threatening cultivated sweetpotato (Ipomoea batatas Lam) in East Africa: Sweet potato feathery mottle virus (SPFMV; genus Potyvirus; Potyviridae), Sweet potato chlorotic stunt virus (SPCSV; genus Crinivirus; Closteroviridae) and Sweet potato mild mottle virus (SPMMV; genus Ipomovirus; Potyviridae). The viruses were serologically detected and the positive results confirmed b...

  13. Cowpea Mosaic Virus-Encoded Protease Does Not Recognize Primary Translation Products of M RNAs from Other Comoviruses.

    Science.gov (United States)

    Goldbach, R; Krijt, J

    1982-09-01

    The protease encoded by the large (B) RNA segment of cowpea mosaic virus was tested for its ability to recognize the in vitro translation products of the small (M) RNA segment from the comoviruses squash mosaic virus, red clover mottle virus, and cowpea severe mosaic virus (CPsMV, strains Dg and Ark), and from the nepovirus tomato black ring virus. Like M RNA from cowpea mosaic virus, the M RNAs from squash mosaic virus, red clover mottle virus, CPsMV-Dg, and CPsMV-Ark were all translated into two large polypeptides with apparent molecular weights which were different for each virus and even for the two CPsMV strains. Neither the in vitro products from squash mosaic virus, red clover mottle virus, and CPsMV M RNAs nor the in vitro product from tomato black ring virus RNA-2 were processed by the cowpea mosaic virus-encoded protease, indicating that the activity of this enzyme is highly specific.

  14. Molecular analysis of yellow fever virus 17DD vaccine strain

    Directory of Open Access Journals (Sweden)

    Paulo R. Post

    1991-06-01

    Full Text Available The Oswaldo Cruz Foundation produces most of the yellow fever (YF vaccine prepared world wide. As part of a broader approach to determine the genetic variability in YF l7D seeds and vaccines and its relevance to viral attenuation the 17DD virus was purifed directly from chick embryo homogenates which is the source of virus used for vaccination of millions of people in Brazil and other countries for half a century. Neutralization and hemagglutination tests showed that the purified virus is similar to the original stock. Furthermore, radioimmune precipitation of 35S-methionine-labeled viral proteins using mouse hyperimmune ascitic fluid revealed identical patterns for the purified 17DD virus and the YF l7D-204 strain except for the 17DD E protein which migrated slower on SDS-PAGE. This difference is likely to be due to N-linked glycosylation. Finally, comparison by northern blot nybridization of virion RNAs of purified 17DD with two other strains of YF virus only fenome-sized molecules for all three viruses. These observations suggest that vaccine phenotype is primarily associated with the accumulation of mutations.

  15. Molecular identification based on coat protein sequences of the Barley yellow dwarf virus from Brazil

    Directory of Open Access Journals (Sweden)

    Talita Bernardon Mar

    2013-12-01

    Full Text Available Yellow dwarf disease, one of the most important diseases of cereal crops worldwide, is caused by virus species belonging to the Luteoviridae family. Forty-two virus isolates obtained from oat (Avena sativa L., wheat (Triticum aestivum L., barley (Hordeum vulgare L., corn (Zea mays L., and ryegrass (Lolium multiflorum Lam. collected between 2007 and 2008 from winter cereal crop regions in southern Brazil were screened by polymerase chain reaction (PCR with primers designed on ORF 3 (coat protein - CP for the presence of Barley yellow dwarf virus and Cereal yellow dwarf virus (B/CYDV. PCR products of expected size (~357 bp for subgroup II and (~831 bp for subgroup I were obtained for three and 39 samples, respectively. These products were cloned and sequenced. The subgroup II 3' partial CP amino acid deduced sequences were identified as BYDV-RMV (92 - 93 % of identity with "Illinois" Z14123 isolate. The complete CP amino acid deduced sequences of subgroup I isolates were confirmed as BYDV-PAV (94 - 99 % of identity and established a very homogeneous group (identity higher than 99 %. These results support the prevalence of BYDV-PAV in southern Brazil as previously diagnosed by Enzyme-Linked Immunosorbent Assay (ELISA and suggest that this population is very homogeneous. To our knowledge, this is the first report of BYDV-RMV in Brazil and the first genetic diversity study on B/CYDV in South America.

  16. The 42-kDa coat protein of Andean potato mottle virus acts as a transcriptional activator in yeast

    Directory of Open Access Journals (Sweden)

    Vidal M.S.

    2002-01-01

    Full Text Available Interactions of viral proteins play an important role in the virus life cycle, especially in capsid assembly. Andean potato mottle comovirus (APMoV is a plant RNA virus with a virion formed by two coat proteins (CP42 and CP22. Both APMoV coat protein open reading frames were cloned into pGBT9 and pGAD10, two-hybrid system vectors. HF7c yeast cells transformed with the p9CP42 construct grew on yeast dropout selection media lacking tryptophan and histidine. Clones also exhibited ß-galactosidase activity in both qualitative and quantitative assays. These results suggest that CP42 protein contains an amino acid motif able to activate transcription of His3 and lacZ reporter genes in Saccharomyces cerevisiae. Several deletions of the CP42 gene were cloned into the pGBT9 vector to locate the region involved in this activation. CP42 constructions lacking 12 residues from the C-terminal region and another one with 267 residues deleted from the N-terminus are still able to activate transcription of reporter genes. However, transcription activation was not observed with construction p9CP42deltaC57, which does not contain the last 57 amino acid residues. These results demonstrate that a transcription activation domain is present at the C-terminus of CP42 between residues 267 and 374.

  17. Cowpea Mosaic Virus-Encoded Protease Does Not Recognize Primary Translation Products of M RNAs from Other Comoviruses

    OpenAIRE

    Goldbach, Rob; Krijt, Jette

    1982-01-01

    The protease encoded by the large (B) RNA segment of cowpea mosaic virus was tested for its ability to recognize the in vitro translation products of the small (M) RNA segment from the comoviruses squash mosaic virus, red clover mottle virus, and cowpea severe mosaic virus (CPsMV, strains Dg and Ark), and from the nepovirus tomato black ring virus. Like M RNA from cowpea mosaic virus, the M RNAs from squash mosaic virus, red clover mottle virus, CPsMV-Dg, and CPsMV-Ark were all translated int...

  18. Reference gene selection for quantitative real-time PCR analysis in virus infected cells: SARS corona virus, Yellow fever virus, Human Herpesvirus-6, Camelpox virus and Cytomegalovirus infections

    Directory of Open Access Journals (Sweden)

    Müller Marcel A

    2005-02-01

    Full Text Available Abstract Ten potential reference genes were compared for their use in experiments investigating cellular mRNA expression of virus infected cells. Human cell lines were infected with Cytomegalovirus, Human Herpesvirus-6, Camelpox virus, SARS coronavirus or Yellow fever virus. The expression levels of these genes and the viral replication were determined by real-time PCR. Genes were ranked by the BestKeeper tool, the GeNorm tool and by criteria we reported previously. Ranking lists of the genes tested were tool dependent. However, over all, β-actin is an unsuitable as reference gene, whereas TATA-Box binding protein and peptidyl-prolyl-isomerase A are stable reference genes for expression studies in virus infected cells.

  19. Selective depletion of organic matter in mottled podzol horizons

    NARCIS (Netherlands)

    Buurman, P.; Schellekens, J.; Fritze, H.; Nierop, K.G.J.

    2007-01-01

    Abstract: Some well-drained podzols on quartz sands in the Netherlands and neighbouring Belgium and Germany show mottling in all horizons due to selective removal of organic matter. Phospholipid analysis and morphology of the mottles suggests that this removal is due to activity of fungi.

  20. Selective depletion of organic matter in mottled podzol horizons

    NARCIS (Netherlands)

    Buurman, P.; Schellekens, J.F.P.; Fritze, H.; Nierop, K.G.J.

    2007-01-01

    Some well-drained podzols on quartz sands in the Netherlands and neighbouring Belgium and Germany show mottling in all horizons due to selective removal of organic matter. Phospholipid analysis and morphology of the mottles suggests that this removal is due to a combination of bacteria, fungi, and

  1. Phylogenetic relationships and the occurrence of interspecific recombination between beet chlorosis virus (BChV) and Beet mild yellowing virus (BMYV).

    Science.gov (United States)

    Kozlowska-Makulska, Anna; Hasiow-Jaroszewska, Beata; Szyndel, Marek S; Herrbach, Etienne; Bouzoubaa, Salah; Lemaire, Olivier; Beuve, Monique

    2015-02-01

    Samples containing two viruses belonging to the genus Polerovirus, beet chlorosis virus (BChV) and beet mild yellowing virus (BMYV), were collected from French and Polish sugar beet fields. The molecular properties of 24 isolates of BChV and BMYV were investigated, and their genetic diversity was examined in the coat protein (CP)- and P0-encoding genes. For the first time, we have demonstrated that beet polerovirus populations include recombinants between BChV and BMYV containing breakpoints within the CP gene. Moreover, a partial correlation between geographic origin and phylogenetic clustering was observed for BMYV isolates.

  2. Rabies virus in a pregnant naturally infected southern yellow bat (Lasiurus ega

    Directory of Open Access Journals (Sweden)

    SD Allendorf

    2011-01-01

    Full Text Available Current knowledge on bat lyssavirus infections in their native hosts is limited and little is known about the virulence, virus dissemination and transmission among free-living insectivorous bats. The present study is a brief description of rabies virus (RABV dissemination in tissues of a naturally infected pregnant southern yellow bat (Lasiurus ega and its fetuses, obtained by reverse-transcriptase polymerase chain reaction (RT-PCR. The RT-PCR was positive in samples from the brain, salivary gland, tongue, lungs, heart, kidneys and liver. On the other hand, the placenta, three fetuses, spleen, intestine and brown fat tissue tested negative. This research demonstrated the absence of rabies virus in the fetuses, thus, in this specific case, the transplacentary transmission was not observed.

  3. MEK/ERK activation plays a decisive role in yellow fever virus replication: implication as an antiviral therapeutic target.

    Science.gov (United States)

    Albarnaz, Jonas D; De Oliveira, Leonardo C; Torres, Alice A; Palhares, Rafael M; Casteluber, Marisa C; Rodrigues, Claudiney M; Cardozo, Pablo L; De Souza, Aryádina M R; Pacca, Carolina C; Ferreira, Paulo C P; Kroon, Erna G; Nogueira, Maurício L; Bonjardim, Cláudio A

    2014-11-01

    Exploiting the inhibition of host signaling pathways aiming for discovery of potential antiflaviviral compounds is clearly a beneficial strategy for the control of life-threatening diseases caused by flaviviruses. Here we describe the antiviral activity of the MEK1/2 inhibitor U0126 against Yellow fever virus 17D vaccine strain (YFV-17D). Infection of VERO cells with YFV-17D stimulates ERK1/2 phosphorylation early during infection. Pharmacological inhibition of MEK1/2 through U0126 treatment of VERO cells blockades not only the YFV-stimulated ERK1/2 phosphorylation, but also inhibits YFV replication by ∼99%. U0126 was also effective against dengue virus (DENV-2 and -3) and Saint-Louis encephalitis virus (SLEV). Levels of NS4AB, as detected by immunofluorescence, are diminished upon treatment with the inhibitor, as well as the characteristic endoplasmic reticulum membrane invagination stimulated during the infection. Though not protective, treatment of YFV-infected, adult BALB/c mice with U0126 resulted in significant reduction of virus titers in brains. Collectively, our data suggest the potential targeting of the MEK1/2 kinase as a therapeutic tool against diseases caused by flaviviruses such as yellow fever, adverse events associated with yellow fever vaccination and dengue. Copyright © 2014 Elsevier B.V. All rights reserved.

  4. Identification of Mungbean yellow mosaic India virus infecting Vigna mungo var. silvestris L.

    Directory of Open Access Journals (Sweden)

    Kamaal NAIMUDDIN

    2011-05-01

    Full Text Available Normal 0 14 false false false IT ZH-TW X-NONE MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Tabella normale"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin-top:0cm; mso-para-margin-right:0cm; mso-para-margin-bottom:10.0pt; mso-para-margin-left:0cm; line-height:115%; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} Yellow mosaic of Vigna mungo var.  silvestris, a wild relative of blackgram (Vigna mungo [L.] Hepper, was noticed at the Indian Institute of Pulses Research, Kanpur, India during 2008–2010, with an incidence of 100 per cent. The observed symptoms, consisting of veinal yellowing and scattered bright yellow spots, were suggestive of infection with a begomovirus. To characterize the virus, several sets of primer pairs were designed to amplify the targeted DNA fragments of the causal virus. The sequence data revealed that the coat protein (AV1 gene of the begomovirus under study contained a single open reading frame with 774 nucleotides, coding for 257 amino acids. Comparative analysis of the coat protein (AV1 gene of the virus under study (FJ821189 showed a 97 and 99% similarity with Mungbean yellow mosaic India virus (MYMIV-Mungbean strain at the nucleotide and the amino acid levels respectively. Sequence homology of different genes (AC1, AC2, AC3 and AC4 of the isolate under study (FJ663015 with MYMIV-Mungbean (EU523045 was 94–97% for the nucleotides and 91–99% for the amino acids sequence. Therefore, the begomovirus infecting V. mungo var. silvestris at Kanpur is to be considered a strain of MYMIV and is

  5. [Yellow fever virus, dengue 2 and other arboviruses isolated from mosquitos, in Burkina Faso, from 1983 to 1986. Entomological and epidemiological considerations].

    Science.gov (United States)

    Robert, V; Lhuillier, M; Meunier, D; Sarthou, J L; Monteny, N; Digoutte, J P; Cornet, M; Germain, M; Cordellier, R

    1993-01-01

    An arbovirus surveillance was carried out in Burkina Faso from 1983 to 1986. It was based on crepuscular catches of mosquitoes on human bait in some wooded areas and in one town. The total collection was 228 catches with an average of 8 men per catch. The total number of mosquitoes caught was 44,956 among which 32,010 potential vector of yellow fever; all these mosquitoes were analysed for arbovirology. In the south-western part of the country (region of Bobo-Dioulasso), surveillance was conducted each year from August to November, whilst the circulation of Aedes-borne arboviruses is well known to be favoured. In 1983, 1984 and 1986, seven strains of yellow fever virus were isolated in circumstances remarkably similar. They came from selvatic areas and never from the town. They concerned only Aedes (Stegomyia) luteocephalus which is the very predominant potential vector of yellow fever in the region. They were obtained in low figure, between 1 and 4 per year. They occurred from 27th of October to 21th of November. These observations confirm that the southern portion of the Sudan savanna zone of West Africa is the setting of a customary circulation of yellow fever virus and therefore belongs to the endemic emergence zone. In 1986, two strains of dengue 2 virus were isolated. One concerned Ae. luteocephalus from the selvatic area, the other Ae. (St.) aegypti from the heart of town. These data suggest two distinct cycles for dengue 2 virus, one urban and one selvatic, which could coexist simultaneously in the same region. In the south-eastern part of the country (region of Fada-N'Gourma) a yellow fever epidemic occurred between September and December 1983; its study has enable to precise their entomological aspects. The entomological inoculation rate of yellow fever virus has been evaluated to 22 infected bites per man during the month of october, for a man living close to forest gallery. 25 strains of yellow fever virus strains was isolated from Ae. (Diceromyia

  6. Molecular evidence for the occurrence of beet western yellows virus on chickpea in Morocco.

    NARCIS (Netherlands)

    Fortass, M.; Wilk, van der F.; Heuvel, van de J.F.J.M.; Goldbach, R.W.

    1997-01-01

    A luteovirus isolate infecting chickpea in Morocco was experimentally transmitted by Myzus persicae to Physalis floridana, on which it produced mild symptoms. When tested in western blots against antisera to known legume luteoviruses, this isolate reacted strongly to beet western yellows virus

  7. Infection of the whitefly Bemisia tabaci with Rickettsia spp. alters its interactions with Tomato yellow leaf curl virus

    Science.gov (United States)

    Numerous animal and plant viruses are transmitted by arthropod vectors in a persistent, circulative manner. Tomato yellow leaf curl virus (TYLCV) is transmitted by the sweet potato whitefly Bemisia tabaci. Here we report that infection with Rickettsia spp., a facultative endosymbiont of whiteflies...

  8. Yellow Fever Vaccine: What You Need to Know

    Science.gov (United States)

    ... How can I prevent yellow fever? Yellow fever vaccine Yellow fever vaccine can prevent yellow fever. Yellow fever vaccine ... such as those containing DEET. 3 Yellow fever vaccine Yellow fever vaccine is a live, weakened virus. It is ...

  9. Quantifying changes and influences on mottled duck density in Texas

    Science.gov (United States)

    Ross, Beth; Haukos, David A.; Walther, Patrick

    2018-01-01

    Understanding the relative influence of environmental and intrinsic effects on populations is important for managing and conserving harvested species, especially those species inhabiting changing environments. Additionally, climate change can increase the uncertainty associated with management of species in these changing environments, making understanding factors affecting their populations even more important. Coastal ecosystems are particularly threatened by climate change; the combined effects of increasing severe weather events, sea level rise, and drought will likely have non-linear effects on coastal marsh wildlife species and their associated habitats. A species of conservation concern that persists in these coastal areas is the mottled duck (Anas fulvigula). Mottled ducks in the western Gulf Coast are approximately 50% below target abundance numbers established by the Gulf Coast Joint Venture for Texas and Louisiana, USA. Although evidence for declines in mottled duck abundance is apparent, specific causes of the decrease remain unknown. Our goals were to determine where the largest declines in mottled duck population were occurring along the system of Texas Gulf Coast National Wildlife Refuges and quantify the relative contribution of environmental and intrinsic effects on changes to relative population density. We modeled aerial survey data of mottled duck density along the Texas Gulf Coast from 1986–2015 to quantify effects of extreme weather events on an index to mottled duck density using the United States Climate Extremes Index and Palmer Drought Severity Index. Our results indicate that decreases in abundance are best described by an increase in days with extreme 1-day precipitation from June to November (hurricane season) and an increase in drought severity. Better understanding those portions of the life cycle affected by environmental conditions, and how to manage mottled duck habitat in conjunction with these events will likely be key to

  10. Impact of Electrostatic Assist on Halftone Mottle in Shrink Films

    Directory of Open Access Journals (Sweden)

    Akshay V. Joshi

    2015-09-01

    Full Text Available Gravure printing delivers intricate print quality and exhibit better feasibility for printing long run packaging jobs. PVC and PETG are widely used shrink films printed by gravure process. The variation in ink transfer from gravure cells on to the substrate results in print mottle. The variation is inevitable and requires close monitoring with tight control on process parameters to deliver good dot fidelity. The electrostatic assist in gravure improves the ink transfer efficiency but is greatly influenced by ESA parameters such as air gap (distance between charge bar and impression roller and voltage. Moreover, it is imperative to study the combined effect of ESA and gravure process parameters such as line screen, viscosity and speed for the minimization of half-tone mottle in shrink films. A general full factorial design was performed for the above mentioned parameters to evaluate half-tone mottle. The significant levels of both the main and interactions were studied by ANOVA approach. The statistical analysis revealed the significance of all the process parameters with viscosity, line screen and voltage being the major contributors in minimization of half-tone mottle. The optimized setting showed reduction in halftone mottle by 33% and 32% for PVC and PET-G respectively. The developed regression model was tested that showed more than 95% predictability. Furthermore, the uniformity of dot was measured by image to non-image area (ratio distribution. The result showed reduction in halftone mottle with uniform dot distribution.

  11. Clinical and laboratory features of dengue virus-infected travellers previously vaccinated against yellow fever

    NARCIS (Netherlands)

    Teichmann, Dieter; Göbels, Klaus; Niedrig, Matthias; Grobusch, Martin P.

    2003-01-01

    Dengue is a mosquito-borne viral infection endemic throughout the tropics and subtropics. The global prevalence of dengue has grown dramatically in recent years and it has become a major international public health concern. The close taxonomic relationships between yellow fever and dengue viruses

  12. Four viruses infecting figs in Western Saudi Arabia

    Directory of Open Access Journals (Sweden)

    Amal Y. ALDHEBIANI

    2015-12-01

    Full Text Available Many diseases are compromising fig production in Saudi Arabia and in particular those caused by viruses. RT-PCR assays were conducted on 80 samples collected from four fig-growing provinces in the West Mecca region of Saudi Arabia, including the Fatima, Khulais, Rabigh and Alshifa valleys. Samples consisted of leaf tissues taken from caprifig and common fig trees. The presence of Fig mosaic virus (FMV, Fig leaf mottle-associated virus 1 (FLMaV-1, Fig leaf mottle-associated virus 2 (FLMaV-2 and Fig mild mottle-associated virus (FMMaV was assessed from the samples. RT-PCR results showed that all four viruses were present in the surveyed areas with different proportions of infection. Incidence was 69% of samples, with a peak of 80%, from the Alshifa and Fatima valleys, 60% from Rabigh and 55% from Khulais valley. FLMaV-1 was the prevailing virus (55% of samples, followed by FMV (34%, whereas FLMaV-2 (11% of samples and FMMaV (6% were less common. Most of the mosaic symptoms observed in surveyed fig orchards occurred with the presence of FMV. However, many other symptoms remained unexplained because of the arduous task of determining the involvement of other fig-infecting viruses with mosaic disease. This is the first report of FMMaV and FLMaV-2 in Saudi Arabia, and of FMV and FLMaV-1 in western Saudi Arabia. The virus status of this crop is probably compromised and a sanitation programme is required to produce healthy plant material in Saudi Arabia.

  13. Colour break in reverse bicolour daffodils is associated with the presence of Narcissus mosaic virus

    Directory of Open Access Journals (Sweden)

    Davies Kevin M

    2011-08-01

    Full Text Available Abstract Background Daffodils (Narcissus pseudonarcissus are one of the world's most popular ornamentals. They also provide a scientific model for studying the carotenoid pigments responsible for their yellow and orange flower colours. In reverse bicolour daffodils, the yellow flower trumpet fades to white with age. The flowers of this type of daffodil are particularly prone to colour break whereby, upon opening, the yellow colour of the perianth is observed to be 'broken' into patches of white. This colour break symptom is characteristic of potyviral infections in other ornamentals such as tulips whose colour break is due to alterations in the presence of anthocyanins. However, reverse bicolour flowers displaying colour break show no other virus-like symptoms such as leaf mottling or plant stunting, leading some to argue that the carotenoid-based colour breaking in reverse bicolour flowers may not be caused by virus infection. Results Although potyviruses have been reported to cause colour break in other flower species, enzyme-linked-immunoassays with an antibody specific to the potyviral family showed that potyviruses were not responsible for the occurrence of colour break in reverse bicolour daffodils. Colour break in this type of daffodil was clearly associated with the presence of large quantities of rod-shaped viral particles of lengths 502-580 nm in tepals. Sap from flowers displaying colour break caused red necrotic lesions on Gomphrena globosa, suggesting the presence of potexvirus. Red necrotic lesions were not observed in this indicator plant when sap from reverse bicolour flowers not showing colour break was used. The reverse transcriptase polymerase reactions using degenerate primers to carla-, potex- and poty-viruses linked viral RNA with colour break and sequencing of the amplified products indicated that the potexvirus Narcissisus mosaic virus was the predominant virus associated with the occurrence of the colour break

  14. Detection and transmission of Carrot torrado virus, a novel putative member of the Torradovirus genus.

    Science.gov (United States)

    Rozado-Aguirre, Zuriñe; Adams, Ian; Collins, Larissa; Fox, Adrian; Dickinson, Matthew; Boonham, Neil

    2016-09-01

    A new Torradovirus tentatively named Carrot torrado virus (CaTV) was an incidental finding following a next generation sequencing study investigating internal vascular necrosis in carrot. The closest related viruses are Lettuce necrotic leaf curl virus (LNLCV) found in the Netherlands in 2011 and Motherwort yellow mottle virus (MYMoV) found in Korea in 2014. Primers for reverse transcriptase-PCR (RT-PCR) and RT-qPCR were designed with the aim of testing for the presence of virus in plant samples collected from the field. Both methods successfully amplified the target from infected samples but not from healthy control samples. The specificity of the CaTV assay was also checked against other known carrot viruses and no cross-reaction was seen. A comparative study between methods showed RT-qPCR was the most reliable method, giving positive results in samples where RT-PCR fails. Evaluation of the Ct values following RT-qPCR and a direct comparison demonstrated this was due to improved sensitivity. The previous published Torradovirus genus specific RT-PCR primers were tested and shown to detect CaTV. Also, virus transmission experiments carried out suggest that unlike other species of the same genus, Carrot torrado virus could be aphid-transmitted. Copyright © 2016 Elsevier B.V. All rights reserved.

  15. Circulation of antibodies against yellow fever virus in a simian population in the area of Porto Primavera Hydroelectric Plant, São Paulo, Brazil.

    Science.gov (United States)

    Lima, Maura Antonia; Romano-Lieber, Nicolina Silvana; Duarte, Ana Maria Ribeiro de Castro

    2010-01-01

    Yellow fever (YF) is an acute viral infectious disease transmitted by mosquitoes which occurs in two distinct epidemiological cycles: sylvatic and urban. In the sylvatic cycle, the virus is maintained by monkey's infection and transovarian transmission in vectors. Surveillance of non-human primates is required for the detection of viral circulation during epizootics, and for the identification of unaffected or transition areas. An ELISA (enzyme-linked immunosorbent assay) was standardized for estimation of the prevalence of IgG antibodies against yellow fever virus in monkey sera (Alouatta caraya) from the reservoir area of Porto Primavera Hydroelectric Plant, in the state of São Paulo, Brazil. A total of 570 monkey sera samples were tested and none was reactive to antibodies against yellow fever virus. The results corroborate the epidemiology of yellow fever in the area. Even though it is considered a transition area, there were no reports to date of epizootics or yellow fever outbreaks in humans. Also, entomological investigations did not detect the presence of vectors of this arbovirus infection. ELISA proved to be fast, sensitive, an adequate assay, and an instrument for active search in the epidemiological surveillance of yellow fever allowing the implementation of prevention actions, even before the occurrence of epizootics.

  16. Live Zika virus chimeric vaccine candidate based on a yellow fever 17-D attenuated backbone

    OpenAIRE

    Nougairede, Antoine; Klitting, Raphaelle; Aubry, Fabien; Gilles, Magali; Touret, Franck; De Lamballerie, Xavier

    2018-01-01

    Zika virus (ZIKV) recently dispersed throughout the tropics and sub-tropics causing epidemics associated with congenital disease and neurological complications. There is currently no commercial vaccine for ZIKV. Here we describe the initial development of a chimeric virus containing the prM/E proteins of a ZIKV epidemic strain incorporated into a yellow fever 17-D attenuated backbone. Using the versatile and rapid ISA (Infectious Subgenomic Amplicons) reverse genetics method, we compared diff...

  17. Need yellow fever vaccine? Plan ahead

    Science.gov (United States)

    ... Submit What's this? Submit Button Past Emails Need yellow fever vaccine? Plan ahead. Language: English (US) Español (Spanish) ... none were from the United States). What is yellow fever? Yellow fever is caused by a virus that ...

  18. Oral receptivity of Aedes aegypti from Cape Verde for yellow fever, dengue, and chikungunya viruses.

    Science.gov (United States)

    Vazeille, Marie; Yébakima, André; Lourenço-de-Oliveira, Ricardo; Andriamahefazafy, Barrysson; Correira, Artur; Rodrigues, Julio Monteiro; Veiga, Antonio; Moreira, Antonio; Leparc-Goffart, Isabelle; Grandadam, Marc; Failloux, Anna-Bella

    2013-01-01

    At the end of 2009, 21,313 cases of dengue-3 virus (DENV-3) were reported in the islands of Cape Verde, an archipelago located in the Atlantic Ocean 570 km from the coast of western Africa. It was the first dengue outbreak ever reported in Cape Verde. Mosquitoes collected in July 2010 in the city of Praia, on the island of Santiago, were identified morphologically as Aedes aegypti formosus. Using experimental oral infections, we found that this vector showed a moderate ability to transmit the epidemic dengue-3 virus, but was highly susceptible to chikungunya and yellow fever viruses.

  19. Polyamine biosynthesis and the replication of turnip yellow mosaic virus

    International Nuclear Information System (INIS)

    Balint, R.F.

    1984-01-01

    Turnip yellow mosaic virus (TYMV) contains large amounts of nonexchangeable spermidine and induces an accumulation of spermidine in infected Chinese cabbage. By seven days after inoculation, a majority of protoplasts isolated from newly-emerging leaves stain with fluorescent antibody to the virus. These protoplasts contain 1-2 x 10 6 virions per cell and continue to produce virus in culture for at least 48 hours. [ 14 C]-Spermidine (10 μM) was taken up by these cells in amounts comparable to the original endogenous pool within 24 hours. However, the spermidine content of the cell was only marginally affected, implying considerable regulation of the endogenous pool(s). Putrescine and spermine were major products of the metabolism of exogenous spermidine. Radioactivity from exogenous [ 14 C]-spermidine was also readily incorporated into the nucleic acid-containing component of the virus, where it appeared as both spermidine and spermine. Thus, newly-formed virions contained predominantly newly-synthesized spermidine and spermine. However, inhibition of spermidine synthesis by dicyclohexylamine (DCHA) led to incorporation of pre-existing spermidine and increased amounts of spermine into newly-formed virions. The latter results were tested and confirmed in a second cellular system, consisting of health protoplasts infected with TYMC in vitro

  20. Phylogeny of Yellow Fever Virus, Uganda, 2016.

    Science.gov (United States)

    Hughes, Holly R; Kayiwa, John; Mossel, Eric C; Lutwama, Julius; Staples, J Erin; Lambert, Amy J

    2018-08-17

    In April 2016, a yellow fever outbreak was detected in Uganda. Removal of contaminating ribosomal RNA in a clinical sample improved the sensitivity of next-generation sequencing. Molecular analyses determined the Uganda yellow fever outbreak was distinct from the concurrent yellow fever outbreak in Angola, improving our understanding of yellow fever epidemiology.

  1. Simultaneous Detection of Mixed Infection of Onion yellow dwarf virus and an Allexivirus in RT-PCR for Ensuring Virus Free Onion Bulbs.

    Science.gov (United States)

    Kumar, Sandeep; Baranwal, V K; Joshi, Subodh; Arya, Meenakshi; Majumder, S

    2010-06-01

    Reduced seed production in onion is associated with Onion yellow dwarf virus (OYDV), a filamentous Potyvirus. Onion is also infected with other filamentous virus particles suspected to be Allexivirus. RT-PCR was used to detect mixed infection of both the viruses in leaves and bulbs. A duplex RT-PCR was developed, which simultaneously detected the presence of these two viruses in winter (Rabi) onion bulb. In summer (Kharif) onion bulbs only Allexivirus was detected. The absence of OYDV in summer crop is discussed. The sequencing of RT-PCR amplified products confirmed the identity of OYDV and Allexivirus, the latter showing closer identity to Garlic virus C (GVC)/Garlic mite-borne mosaic virus. This makes the first detection of an Allexivirus in onion crop in India. The duplex RT-PCR to detect these viruses (OYDV and Allexivirus) would be an improvement for indexing of viruses in onion bulbs for seed production.

  2. Characterization of the complete genome of euonymus yellow vein associated virus, a distinct member of the genus Potexvirus, family Alphaflexiviridae, isolated from Euonymus bungeanus Maxim in Liaoning, Northern China.

    Science.gov (United States)

    Yang, Caixia; Han, Tong; Fu, Jingjing; Liao, Yiming; Chen, Sha

    2018-02-01

    In August 2016, a yellow vein disease was observed on leaves of Euonymus bungeanus Maxim (Euonymus, Celastraceae) in Liaoning, China. Virions measuring 750 × 13 nm were observed in a sample from the diseased plant. A potexvirus was detected in the sample by small-RNA deep sequencing analysis and recovered by traditional cloning. The genome of this potexvirus consists of 7,279 nucleotides, excluding the poly(A) tail at the 3' end, and contains five open reading frames (ORFs). Based on the nucleotide and amino acid sequences of the coat protein gene, the virus shared the highest sequence similarity with white clover mosaic virus (WCMV, X16636) (40.1%) and clover yellow mosaic virus (ClYMV, D00485) (37.1%). Phylogenetic analysis showed that the virus clustered with potexviruses and is most closely related to strawberry mild yellow edge virus. These results indicate that this virus is a distinct member of the genus Potexvirus, for which the name euonymus yellow vein associated virus (EuYVAV) is proposed. To our knowledge, this is the first report of a potexvirus on E. bungeanus.

  3. Effect of virus infection on symplastic transport of fluorescent tracers in Nicotiana clevelandii leaf epidermis.

    Science.gov (United States)

    Derrick, P M; Barker, H; Oparka, K J

    1990-07-01

    The molecular weight exclusion limit of plasmodesmata in subveinal epidermal cells of Nicotiana clevelandii (Gray) leaves was estimated by microinjection and fluorescence microscopy using fluorescein isothiocyanate-peptide conjugates, carboxyfluorescein and Lucifer Yellow CH. The largest fluorochrome which moved symplastically between cells had a molecular weight of 749, although movement did not appear to depend purely on molecular weight parameters. Systemic infection of plants by tobacco rattle tobravirus, tomato black ring nepovirus or potato Y potyvirus did not alter the limits of plasmodesmatal conductance of the fluorochromes. However, carrot mottle umbravirus and groundnut rosette umbravirus diminished the symplastic mobility of some fluorescent tracers. These results imply that intercellular movement of these viruses does not involve a long-lasting increase in the plasmodesmatal molecular size exclusion limit.

  4. Inspirations on Virus Replication and Cell-to-Cell Movement from Studies Examining the Cytopathology Induced by Lettuce infectious yellows virus in Plant Cells

    Directory of Open Access Journals (Sweden)

    Wenjie Qiao

    2017-09-01

    Full Text Available Lettuce infectious yellows virus (LIYV is the type member of the genus Crinivirus in the family Closteroviridae. Like many other positive-strand RNA viruses, LIYV infections induce a number of cytopathic changes in plant cells, of which the two most characteristic are: Beet yellows virus-type inclusion bodies composed of vesicles derived from cytoplasmic membranes; and conical plasmalemma deposits (PLDs located at the plasmalemma over plasmodesmata pit fields. The former are not only found in various closterovirus infections, but similar structures are known as ‘viral factories’ or viroplasms in cells infected with diverse types of animal and plant viruses. These are generally sites of virus replication, virion assembly and in some cases are involved in cell-to-cell transport. By contrast, PLDs induced by the LIYV-encoded P26 non-virion protein are not involved in replication but are speculated to have roles in virus intercellular movement. These deposits often harbor LIYV virions arranged to be perpendicular to the plasma membrane over plasmodesmata, and our recent studies show that P26 is required for LIYV systemic plant infection. The functional mechanism of how LIYV P26 facilitates intercellular movement remains unclear, however, research on other plant viruses provides some insights on the possible ways of viral intercellular movement through targeting and modifying plasmodesmata via interactions between plant cellular components and viral-encoded factors. In summary, beginning with LIYV, we review the studies that have uncovered the biological determinants giving rise to these cytopathological effects and their importance in viral replication, virion assembly and intercellular movement during the plant infection by closteroviruses, and compare these findings with those for other positive-strand RNA viruses.

  5. The genome sequence of pepper vein yellows virus (family Luteoviridae, genus Polerovirus).

    Science.gov (United States)

    Murakami, Ritsuko; Nakashima, Nobuhiko; Hinomoto, Norihide; Kawano, Shinji; Toyosato, Tetsuya

    2011-05-01

    The complete genome of pepper vein yellows virus (PeVYV) was sequenced using random amplification of RNA samples isolated from vector insects (Aphis gossypii) that had been given access to PeVYV-infected plants. The PeVYV genome consisted of 6244 nucleotides and had a genomic organization characteristic of members of the genus Polerovirus. PeVYV had highest amino acid sequence identities in ORF0 to ORF3 (75.9 - 91.9%) with tobacco vein distorting polerovirus, with which it was only 25.1% identical in ORF5. These sequence comparisons and previously studied biological properties indicate that PeVYV is a distinctly different virus and belongs to a new species of the genus Polerovirus.

  6. Predicting the presence of whiteflies and tomato yellow leaf curl virus in Florida tomato fields

    Science.gov (United States)

    Florida is one of the leading states for production of fresh market tomatoes. Production is severely affected by Tomato yellow leaf curl virus (TYLCV). The objective of this study was to identify landscape and climatic factors that drive whitefly populations and TYLCV incidence in commercial tomato ...

  7. Presence and Distribution of Oilseed Pumpkin Viruses and Molecular Detection of Zucchini Yellow Mosaic Virus

    Directory of Open Access Journals (Sweden)

    Ana Vučurović

    2009-01-01

    Full Text Available Over the past decade, intensive spread of virus infections of oilseed pumpkin has resulted in significant economic losses in pumpkin crop production, which is currently expanding in our country. In 2007 and 2008, a survey for the presence and distribution of oilseed pumpkin viruses was carried out in order to identify viruses responsible for epidemics and incidences of very destructive symptoms on cucurbit leaves and fruits. Monitoring andcollecting samples of oil pumpkin, as well as other species such as winter and butternut squash and buffalo and bottle gourd with viral infection symptoms, was conducted in several localities of Vojvodina Province. The collected plant samples were tested by DAS-ELISA using polyclonal antisera specific for the detection of six most economically harmful pumpkin viruses: Cucumber mosaic virus (CMV, Zucchini yellow mosaic virus (ZYMV, Watermelon mosaic virus (WMW, Squash mosaic virus (SqMV, Papaya ringspot virus (PRSV and Tobaccoringspot virus (TRSV that are included in A1 quarantine list of harmful organisms in Serbia.Identification of viruses in the collected samples indicated the presence of three viruses, ZYMV, WMV and CMV, in individual and mixed infections. Frequency of the identified viruses varied depending on locality and year of investigations. In 2007, WMV was the most frequent virus (94.2%, while ZYMV was prevalent (98.04% in 2008. High frequency of ZYMV determined in both years of investigation indicated the need for its rapid and reliable molecular detection. During this investigation, a protocol for ZYMVdetection was developed and optimized using specific primers CPfwd/Cprev and commercial kits for total RNA extraction, as well as for RT-PCR. In RT-PCR reaction using these primers, a DNA fragment of approximately 1100 bp, which included coat protein gene, was amplified in the samples of infected pumkin leaves. Although serological methods are still useful for large-scale testing of a great number of

  8. A Novel Benzodiazepine Compound Inhibits Yellow Fever Virus Infection by Specifically Targeting NS4B Protein.

    Science.gov (United States)

    Guo, Fang; Wu, Shuo; Julander, Justin; Ma, Julia; Zhang, Xuexiang; Kulp, John; Cuconati, Andrea; Block, Timothy M; Du, Yanming; Guo, Ju-Tao; Chang, Jinhong

    2016-09-21

    Although a highly effective vaccine is available, the number of yellow fever cases has increased over the past two decades, which highlights the pressing need for antiviral therapeutics. In a high throughput screening campaign, we identified an acetic acid benzodiazepine (BDAA) compound, which potently inhibits yellow fever virus (YFV). Interestingly, while treatment of YFV infected cultures with 2 μM of BDAA reduced the virion production by greater than 2 logs, the compound is not active against 21 other viruses from 14 different viral families. Selection and genetic analysis of drug resistant viruses revealed that substitution of proline at amino acid 219 (P219) of the nonstructural protein 4B (NS4B) with serine, threonine or alanine confers YFV resistance to BDAA without apparent loss of replication fitness in cultured mammalian cells. However, substitution of P219 with glycine confers BDAA resistance with significant loss of replication ability. Bioinformatics analysis predicts that the P219 localizes at the endoplasmic reticulum lumen side of the fifth putative trans-membrane domain of NS4B and the mutation may render the viral protein incapable of interacting with BDAA. Our studies thus revealed important role and structural basis for NS4B protein in supporting YFV replication. Moreover, in YFV-infected hamsters, oral administration of BDAA protected 90% of the animals from death, significantly reduced viral load by greater than 2 logs and attenuated viral infection-induced liver injury and body weight loss. The encouraging preclinical results thus warrant further development of BDAA or its derivatives as antiviral agents to treat yellow fever. Yellow fever is an acute viral hemorrhagic disease which threatens approximately one billion people living in tropical areas of Africa and Latin America. Although a highly effective yellow fever vaccine has been available for more than seven decades, the low vaccination rate fails to prevent outbreaks in at

  9. Next generation sequence analysis of the forage peanut (Arachis pintoi virome

    Directory of Open Access Journals (Sweden)

    Pablo Andrés Gutiérrez Sánchez

    2016-07-01

    resulted in the complete genome assembly of Peanut mottle virus (9707 nt, Turnip yellows virus (5578 nt and two variants of a virus with phylogenetic affinity to the genus Allexivirus. These two variants lack ORF6 present in Allexivirus and probably belong to an uncharacterized genus within the family Alphaflexiviridae. The presence of at least three viruses infecting A. pintoi in Colombia highlights the importance of starting a germplasm clean-up program of the plant material used as seed in this crop.

  10. Efficient, trans-complementing packaging systems for chimeric, pseudoinfectious dengue 2/yellow fever viruses

    International Nuclear Information System (INIS)

    Shustov, Alexandr V.; Frolov, Ilya

    2010-01-01

    In our previous studies, we have stated to build a new strategy for developing defective, pseudoinfectious flaviviruses (PIVs) and applying them as a new type of vaccine candidates. PIVs combined the efficiency of live vaccines with the safety of inactivated or subunit vaccines. The results of the present work demonstrate further development of chimeric PIVs encoding dengue virus 2 (DEN2V) glycoproteins and yellow fever virus (YFV)-derived replicative machinery as potential vaccine candidates. The newly designed PIVs have synergistically functioning mutations in the prM and NS2A proteins, which abolish processing of the latter proteins and make the defective viruses capable of producing either only noninfectious, immature and/or subviral DEN2V particles. The PIV genomes can be packaged to high titers into infectious virions in vitro using the NS1-deficient YFV helper RNAs, and both PIVs and helpers can then be passaged as two-component genome viruses at an escalating scale.

  11. SEED AND POLLEN TTRANSMISSION OF A NEW UNIDENTIFIED MOTTLE DISORDER OF MAIZE IN INDONESIA

    Directory of Open Access Journals (Sweden)

    W. Wakman

    2018-01-01

    Full Text Available A new unidentified mottle disorder of maize Indonesia was found at the Research Institute for Maize and Other Cereals (RIMOC, Maros, South Sulawesi in 1995. Attempts to identify the disorder were made by mechanical inoculation, insect vector (Rhopalosiphum maidis and Peregrinus maidis transmission, seed and pollen transmission, electron microscopy, and serological test. Fifty seeds from each of 22 ears of Arjuna maize plants showing the disorder were planted and symptoms on the seedlings were recorder at 1, 2, and 3 weeks after planting. The percentage of seedlings showing the disorder ranged from 40 to 100. Pollen of affected Arjuna was then used to pollinate four sweet corn female flowers. Hybrid seeds (50 per ear of the crosses were planted and symptoms were recorded at 1, 2, and 3 weeks after planting. The results showed that percentage of seedlings showing the disorder ranged from 22 to 84. Electron microscopy and ELISA tests on 15 viruses and one phytospiroplasma antiserum however, gave negative results. Therefore, maize disorder at Maros was not identical to any known viral disease of maize. It could be a genetical disorder and has been given the name maize mottle.

  12. Screening for sweet potato (Ipomoea batatas (L.)) viruses and their elimination using thermotheraphy-meristem tip culture technique

    International Nuclear Information System (INIS)

    Arkorful, E.

    2012-11-01

    Despite its high potential for food security, production of sweet potato is constrained by viruses which reduce yield by 90%. It is therefore essential to screen for, identify and eliminate these viruses in elite clones before dissemination to farmers. In this study, visual symptomatology and PCR-based techniques were used to identify sweet potato viruses. Visual symptomatology revealed virus associated symptoms ranging from vein clearing, interveinal chlorosis, chlorotic spots, upward curling on leaf edges, leaf narrowing and distortion, purpling, blistering, reduction of the leaf blades and general leaf yellowing in all 22 accessions grown on the field. Disease Incidence (DI) significantly (p≤0.05) varied between accessions with US003 having the lowest (20%) while ten accessions had 90% DI at the end of the study. Index of symptom severity of all plants (ISSap) ranged from 1.08±0.09 to 3.67 ±0.11 with VOTCR003 having the lowest suggesting that it is a moderately susceptible accession while VOTCR002 had the highest suggesting that it is susceptible to viral diseases. Contrarily, index of symptom severity of diseased plants (ISSdp) ranged from 2.00±0.25 to 3.75±0.32. The accession VOTCR002 had the highest ISSdp. Visual symptomatology showed that VOTCR002 had the highest DI, ISSap and ISSdp suggesting that it is highly susceptible to viral diseases. Ten severely infected accessions were tested for Sweet Potato leaf curl virus (SPLCV), Sweet Potato chlorotic stunt virus (SPCSV), Sweet potato feathery mottle virus (SPFMV) and Sweet Potato mild mottle virus (SPMMV) using PCR and RT-PCR techniques. RT-PCR did not amplify any of the virus genomes due to prolonged storage enzymes, In contrast, PCR detected SPLCV in 30% of the accessions. Plants infected with SPLCV were grown in the chamber at 35 degrees celsius for 4 weeks followed by meristem top culture. The regenerants were indexed after ten weeks for SPLCV. Fifty two percent (52.385 od the regenerants were

  13. The structure of melon necrotic spot virus determined at 2.8 Å resolution

    International Nuclear Information System (INIS)

    Wada, Yasunobu; Tanaka, Hideaki; Yamashita, Eiki; Kubo, Chikako; Ichiki-Uehara, Tamaki; Nakazono-Nagaoka, Eiko; Omura, Toshihiro; Tsukihara, Tomitake

    2007-01-01

    The structure of melon necrotic spot virus is reported. The structure of melon necrotic spot virus (MNSV) was determined at 2.8 Å resolution. Although MNSV is classified into the genus Carmovirus of the family Tombusviridae, the three-dimensional structure of MNSV showed a higher degree of similarity to tomato bushy stunt virus (TBSV), which belongs to the genus Tombusvirus, than to carnation mottle virus (CMtV), turnip crinkle virus (TCV) or cowpea mottle virus (CPMtV) from the genus Carmovirus. Thus, the classification of the family Tombusviridae at the genus level conflicts with the patterns of similarity among coat-protein structures. MNSV is one of the viruses belonging to the genera Tombusvirus or Carmovirus that are naturally transmitted in the soil by zoospores of fungal vectors. The X-ray structure of MNSV provides us with a representative structure of viruses transmitted by fungi

  14. Functional requirements of the yellow fever virus capsid protein.

    Science.gov (United States)

    Patkar, Chinmay G; Jones, Christopher T; Chang, Yu-hsuan; Warrier, Ranjit; Kuhn, Richard J

    2007-06-01

    Although it is known that the flavivirus capsid protein is essential for genome packaging and formation of infectious particles, the minimal requirements of the dimeric capsid protein for virus assembly/disassembly have not been characterized. By use of a trans-packaging system that involved packaging a yellow fever virus (YFV) replicon into pseudo-infectious particles by supplying the YFV structural proteins using a Sindbis virus helper construct, the functional elements within the YFV capsid protein (YFC) were characterized. Various N- and C-terminal truncations, internal deletions, and point mutations of YFC were analyzed for their ability to package the YFV replicon. Consistent with previous reports on the tick-borne encephalitis virus capsid protein, YFC demonstrates remarkable functional flexibility. Nearly 40 residues of YFC could be removed from the N terminus while the ability to package replicon RNA was retained. Additionally, YFC containing a deletion of approximately 27 residues of the C terminus, including a complete deletion of C-terminal helix 4, was functional. Internal deletions encompassing the internal hydrophobic sequence in YFC were, in general, tolerated to a lesser extent. Site-directed mutagenesis of helix 4 residues predicted to be involved in intermonomeric interactions were also analyzed, and although single mutations did not affect packaging, a YFC with the double mutation of leucine 81 and valine 88 was nonfunctional. The effects of mutations in YFC on the viability of YFV infection were also analyzed, and these results were similar to those obtained using the replicon packaging system, thus underscoring the flexibility of YFC with respect to the requirements for its functioning.

  15. High Prevalence and Diversity of Hepatitis Viruses in Suspected Cases of Yellow Fever in the Democratic Republic of Congo.

    Science.gov (United States)

    Makiala-Mandanda, Sheila; Le Gal, Frédéric; Ngwaka-Matsung, Nadine; Ahuka-Mundeke, Steve; Onanga, Richard; Bivigou-Mboumba, Berthold; Pukuta-Simbu, Elisabeth; Gerber, Athenaïs; Abbate, Jessica L; Mwamba, Dieudonné; Berthet, Nicolas; Leroy, Eric Maurice; Muyembe-Tamfum, Jean-Jacques; Becquart, Pierre

    2017-05-01

    The majority of patients with acute febrile jaundice (>95%) identified through a yellow fever surveillance program in the Democratic Republic of Congo (DRC) test negative for antibodies against yellow fever virus. However, no etiological investigation has ever been carried out on these patients. Here, we tested for hepatitis A (HAV), hepatitis B (HBV), hepatitis C (HCV), hepatitis D (HDV), and hepatitis E (HEV) viruses, all of which can cause acute febrile jaundice, in patients included in the yellow fever surveillance program in the DRC. On a total of 498 serum samples collected from suspected cases of yellow fever from January 2003 to January 2012, enzyme-linked immunosorbent assay (ELISA) techniques were used to screen for antibodies against HAV (IgM) and HEV (IgM) and for antigens and antibodies against HBV (HBsAg and anti-hepatitis B core protein [HBc] IgM, respectively), HCV, and HDV. Viral loads and genotypes were determined for HBV and HVD. Viral hepatitis serological markers were diagnosed in 218 (43.7%) patients. The seroprevalences were 16.7% for HAV, 24.6% for HBV, 2.3% for HCV, and 10.4% for HEV, and 26.1% of HBV-positive patients were also infected with HDV. Median viral loads were 4.19 × 10 5 IU/ml for HBV (range, 769 to 9.82 × 10 9 IU/ml) and 1.4 × 10 6 IU/ml for HDV (range, 3.1 × 10 2 to 2.9 × 10 8 IU/ml). Genotypes A, E, and D of HBV and genotype 1 of HDV were detected. These high hepatitis prevalence rates highlight the necessity to include screening for hepatitis viruses in the yellow fever surveillance program in the DRC. Copyright © 2017 Makiala-Mandanda et al.

  16. New poleroviruses associated with yellowing symptoms in different vegetable crops in Greece.

    Science.gov (United States)

    Lotos, L; Maliogka, V I; Katis, N I

    2016-02-01

    Four poleroviral isolates from Greece, two from lettuce, one from spinach and one from watermelon showing yellowing symptoms, were molecularly characterized by analyzing the sequence of a large part of the genome spanning from the 3'-terminal part of the RdRp to the end of the CP gene. The sequences were analyzed for their similarity and phylogenetic relationships to other members of the genus Polerovirus as well as for evidence of recombination events. The results revealed the existence of two putatively new viruses: one from lettuce and one from spinach, provisionally named "lettuce yellows virus" and "spinach yellows virus", respectively. Also, a new recombinant virus infecting lettuce, herein named "lettuce mild yellows virus", and a watermelon isolate of pepo aphid-borne yellows virus (PABYV) were identified. Our study highlights the existence of high genetic diversity within the genus Polerovirus, which could be associated with the emergence of new viral diseases in various crops worldwide.

  17. Genome sequence analysis of five Canadian isolates of strawberry mottle virus reveals extensive intra-species diversity and a longer RNA2 with increased coding capacity compared to a previously characterized European isolate.

    Science.gov (United States)

    Bhagwat, Basdeo; Dickison, Virginia; Ding, Xinlun; Walker, Melanie; Bernardy, Michael; Bouthillier, Michel; Creelman, Alexa; DeYoung, Robyn; Li, Yinzi; Nie, Xianzhou; Wang, Aiming; Xiang, Yu; Sanfaçon, Hélène

    2016-06-01

    In this study, we report the genome sequence of five isolates of strawberry mottle virus (family Secoviridae, order Picornavirales) from strawberry field samples with decline symptoms collected in Eastern Canada. The Canadian isolates differed from the previously characterized European isolate 1134 in that they had a longer RNA2, resulting in a 239-amino-acid extension of the C-terminal region of the polyprotein. Sequence analysis suggests that reassortment and recombination occurred among the isolates. Phylogenetic analysis revealed that the Canadian isolates are diverse, grouping in two separate branches along with isolates from Europe and the Americas.

  18. Resistance to Cucurbit aphid-borne yellows virus in Melon Accession TGR-1551.

    Science.gov (United States)

    Kassem, Mona A; Gosalvez, Blanca; Garzo, Elisa; Fereres, Alberto; Gómez-Guillamón, Maria Luisa; Aranda, Miguel A

    2015-10-01

    The genetic control of resistance to Cucurbit aphid-borne yellows virus (CABYV; genus Polerovirus, family Luteoviridae) in the TGR-1551 melon accession was studied through agroinoculation of a genetic family obtained from the cross between this accession and the susceptible Spanish cultivar 'Bola de Oro'. Segregation analyses were consistent with the hypothesis that one dominant gene and at least two more modifier genes confer resistance; one of these additional genes is likely present in the susceptible parent 'Bola de Oro'. Local and systemic accumulation of the virus was analyzed in a time course experiment, showing that TGR-1551 resistance was expressed systemically as a significant reduction of virus accumulation compared with susceptible controls, but not locally in agroinoculated cotyledons. In aphid transmission experiments, CABYV inoculation by aphids was significantly reduced in TGR-1551 plants, although the virus was acquired at a similar rate from TGR-1551 as from susceptible plants. Results of feeding behavior studies using the DC electrical penetration graph technique suggested that viruliferous aphids can salivate and feed from the phloem of TGR-1551 plants and that the observed reduction in virus transmission efficiency is not related to reduced salivation by Aphis gossypii in phloem sieve elements. Since the virus is able to accumulate to normal levels in agroinoculated tissues, our results suggest that resistance of TGR-1551 plants to CABYV is related to impairment of virus movement or translocation after it reaches the phloem sieve elements.

  19. Characterization of recombinant yellow fever-dengue vaccine viruses with human monoclonal antibodies targeting key conformational epitopes.

    Science.gov (United States)

    Lecouturier, Valerie; Berry, Catherine; Saulnier, Aure; Naville, Sophie; Manin, Catherine; Girerd-Chambaz, Yves; Crowe, James E; Jackson, Nicholas; Guy, Bruno

    2018-04-26

    The recombinant yellow fever-17D-dengue virus, live, attenuated, tetravalent dengue vaccine (CYD-TDV) is licensed in several dengue-endemic countries. Although the vaccine provides protection against dengue, the level of protection differs by serotype and warrants further investigation. We characterized the antigenic properties of each vaccine virus serotype using highly neutralizing human monoclonal antibodies (hmAbs) that bind quaternary structure-dependent epitopes. Specifically, we monitored the binding of dengue virus-1 (DENV-1; 1F4), DENV-2 (2D22) or DENV-3 (5J7) serotype-specific or DENV-1-4 cross-reactive (1C19) hmAbs to the four chimeric yellow fever-dengue vaccine viruses (CYD-1-4) included in phase III vaccine formulations using a range of biochemical and functional assays (dot blot, ELISA, surface plasmon resonance and plaque reduction neutralization assays). In addition, we used the "classic" live, attenuated DENV-2 vaccine serotype, immature CYD-2 viruses and DENV-2 virus-like particles as control antigens for anti-serotype-2 reactivity. The CYD vaccine serotypes were recognized by each hmAbs with the expected specificity, moreover, surface plasmon resonance indicated a high functional affinity interaction with the CYD serotypes. In addition, the hmAbs provided similar protection against CYD and wild-type dengue viruses in the in vitro neutralization assay. Overall, these findings demonstrate that the four CYD viruses used in clinical trials display key conformational and functional epitopes targeted by serotype-specific and/or cross-reactive neutralizing human antibodies. More specifically, we showed that CYD-2 displays serotype- specific epitopes present only on the mature virus. This indicates that the CYD-TDV has the ability to elicit antibody specificities which are similar to those induced by the wild type DENV. Future investigations will be needed to address the nature of CYD-TDV-induced responses after vaccine administration, and how these

  20. 1729-IJBCS-Article-Montcho David

    African Journals Online (AJOL)

    Pr GATSING

    (Linares, 2002). Because of the history of O. glaberrima in Africa, the species is expected to be a rich genetic source for adaptability to. African environments as compared to O. sativa. In fact O. glaberrima can provide resistance to various indigenous biotic constraints: rice yellow mottle virus. (Thiémélé et al., 2010), bacterial ...

  1. Analyses of pea necrotic yellow dwarf virus-encoded proteins.

    Science.gov (United States)

    Krenz, Björn; Schießl, Ingrid; Greiner, Eva; Krapp, Susanna

    2017-06-01

    Pea necrotic yellow dwarf virus (PNYDV) is a multipartite, circular, single-stranded DNA plant virus. PNYDV encodes eight proteins and the function of three of which remains unknown-U1, U2, and U4. PNYDV proteins cellular localization was analyzed by GFP tagging and bimolecular fluorescence complementation (BiFC) studies. The interactions of all eight PNYDV proteins were tested pairwise in planta (36 combinations in total). Seven interactions were identified and two (M-Rep with CP and MP with U4) were characterized further. MP and U4 complexes appeared as vesicle-like spots and were localized at the nuclear envelope and cell periphery. These vesicle-like spots were associated with the endoplasmatic reticulum. In addition, a nuclear localization signal (NLS) was mapped for U1, and a mutated U1 with NLS disrupted localized at plasmodesmata and therefore might also have a role in movement. Taken together, this study provides evidence for previously undescribed nanovirus protein-protein interactions and their cellular localization with novel findings not only for those proteins with unknown function, but also for characterized proteins such as the CP.

  2. A protein kinase binds the C-terminal domain of the readthrough protein of Turnip yellows virus and regulates virus accumulation.

    Science.gov (United States)

    Rodriguez-Medina, Caren; Boissinot, Sylvaine; Chapuis, Sophie; Gereige, Dalya; Rastegar, Maryam; Erdinger, Monique; Revers, Frédéric; Ziegler-Graff, Véronique; Brault, Véronique

    2015-12-01

    Turnip yellows virus (TuYV), a phloem-limited virus, encodes a 74kDa protein known as the readthrough protein (RT) involved in virus movement. We show here that a TuYV mutant deleted of the C-terminal part of the RT protein (TuYV-∆RTCter) was affected in long-distance trafficking in a host-specific manner. By using the C-terminal domain of the RT protein as a bait in a yeast two-hybrid screen of a phloem cDNA library from Arabidopsis thaliana we identified the calcineurin B-like protein-interacting protein kinase-7 (AtCIPK7). Transient expression of a GFP:CIPK7 fusion protein in virus-inoculated Nicotiana benthamiana leaves led to local increase of wild-type TuYV accumulation, but not that of TuYV-∆RTCter. Surprisingly, elevated virus titer in inoculated leaves did not result in higher TuYV accumulation in systemic leaves, which indicates that virus long-distance movement was not affected. Since GFP:CIPK7 was localized in or near plasmodesmata, CIPK7 could negatively regulate TuYV export from infected cells. Copyright © 2015 Elsevier Inc. All rights reserved.

  3. Plasmid DNA initiates replication of yellow fever vaccine in vitro and elicits virus-specific immune response in mice

    International Nuclear Information System (INIS)

    Tretyakova, Irina; Nickols, Brian; Hidajat, Rachmat; Jokinen, Jenny; Lukashevich, Igor S.; Pushko, Peter

    2014-01-01

    Yellow fever (YF) causes an acute hemorrhagic fever disease in tropical Africa and Latin America. To develop a novel experimental YF vaccine, we applied iDNA infectious clone technology. The iDNA represents plasmid that encodes the full-length RNA genome of 17D vaccine downstream from a cytomegalovirus (CMV) promoter. The vaccine was designed to transcribe the full-length viral RNA and to launch 17D vaccine virus in vitro and in vivo. Transfection with 10 ng of iDNA plasmid was sufficient to start replication of vaccine virus in vitro. Safety of the parental 17D and iDNA-derived 17D viruses was confirmed in AG129 mice deficient in receptors for IFN-α/β/γ. Finally, direct vaccination of BALB/c mice with a single 20 μg dose of iDNA plasmid resulted in seroconversion and elicitation of virus-specific neutralizing antibodies in animals. We conclude that iDNA immunization approach combines characteristics of DNA and attenuated vaccines and represents a promising vaccination strategy for YF. - Highlights: • The iDNA ® platform combines advantages of DNA and live attenuated vaccines. • Yellow fever (YF) 17D vaccine was launched from iDNA plasmid in vitro and in vivo. • Safety of iDNA-generated 17D virus was confirmed in AG129 mice. • BALB/c mice seroconverted after a single-dose vaccination with iDNA. • YF virus-neutralizing response was elicited in iDNA-vaccinated mice

  4. Plasmid DNA initiates replication of yellow fever vaccine in vitro and elicits virus-specific immune response in mice

    Energy Technology Data Exchange (ETDEWEB)

    Tretyakova, Irina; Nickols, Brian; Hidajat, Rachmat [Medigen, Inc., 8420 Gas House Pike, Suite S, Frederick, MD 21701 (United States); Jokinen, Jenny; Lukashevich, Igor S. [Department of Pharmacology and Toxicology, School of Medicine, Center for Predictive Medicine and Emerging Infectious Diseases, University of Louisville, Louisville, KY (United States); Pushko, Peter, E-mail: ppushko@medigen-usa.com [Medigen, Inc., 8420 Gas House Pike, Suite S, Frederick, MD 21701 (United States)

    2014-11-15

    Yellow fever (YF) causes an acute hemorrhagic fever disease in tropical Africa and Latin America. To develop a novel experimental YF vaccine, we applied iDNA infectious clone technology. The iDNA represents plasmid that encodes the full-length RNA genome of 17D vaccine downstream from a cytomegalovirus (CMV) promoter. The vaccine was designed to transcribe the full-length viral RNA and to launch 17D vaccine virus in vitro and in vivo. Transfection with 10 ng of iDNA plasmid was sufficient to start replication of vaccine virus in vitro. Safety of the parental 17D and iDNA-derived 17D viruses was confirmed in AG129 mice deficient in receptors for IFN-α/β/γ. Finally, direct vaccination of BALB/c mice with a single 20 μg dose of iDNA plasmid resulted in seroconversion and elicitation of virus-specific neutralizing antibodies in animals. We conclude that iDNA immunization approach combines characteristics of DNA and attenuated vaccines and represents a promising vaccination strategy for YF. - Highlights: • The iDNA{sup ®} platform combines advantages of DNA and live attenuated vaccines. • Yellow fever (YF) 17D vaccine was launched from iDNA plasmid in vitro and in vivo. • Safety of iDNA-generated 17D virus was confirmed in AG129 mice. • BALB/c mice seroconverted after a single-dose vaccination with iDNA. • YF virus-neutralizing response was elicited in iDNA-vaccinated mice.

  5. The genome sequence of pepper vein yellows virus (family Luteoviridae, genus Polerovirus)

    OpenAIRE

    Murakami, Ritsuko; Nakashima, Nobuhiko; Hinomoto, Norihide; Kawano, Shinji; Toyosato, Tetsuya

    2011-01-01

    The complete genome of pepper vein yellows virus (PeVYV) was sequenced using random amplification of RNA samples isolated from vector insects (Aphis gossypii) that had been given access to PeVYV-infected plants. The PeVYV genome consisted of 6244 nucleotides and had a genomic organization characteristic of members of the genus Polerovirus. PeVYV had highest amino acid sequence identities in ORF0 to ORF3 (75.9 - 91.9%) with tobacco vein distorting polerovirus, with which it was only 25.1% iden...

  6. Coat protein sequence shows that Cucumber mosaic virus isolate

    Indian Academy of Sciences (India)

    A viral disease was identified on geraniums (Pelargonium spp.) grown in a greenhouse at the Institute of Himalayan Bioresource Technology (IHBT), Palampur, exhibiting mild mottling and stunting. The causal virus (Cucumber mosaic virus, CMV) was identified and characterized on the basis of host range, aphid ...

  7. Seroprevalence of yellow fever virus in selected health facilities in Western Kenya from 2010 to 2012.

    Science.gov (United States)

    Kwallah, Allan ole; Inoue, Shingo; Thairu-Muigai, Anne Wangari; Kuttoh, Nancy; Morita, Kouichi; Mwau, Matilu

    2015-01-01

    Yellow fever (YF), which is caused by a mosquito-borne virus, is an important viral hemorrhagic fever endemic in equatorial Africa and South America. Yellow fever virus (YFV) is the prototype of the family Flaviviridae and genus Flavivirus. The aim of this study was to determine the seroprevalence of YFV in selected health facilities in Western Kenya during the period 2010-2012. A total of 469 serum samples from febrile patients were tested for YFV antibodies using in-house IgM-capture ELISA, in-house indirect IgG ELISA, and 50% focus reduction neutralization test (FRNT50). The present study did not identify any IgM ELISA-positive cases, indicating absence of recent YFV infection in the area. Twenty-eight samples (6%) tested positive for YFV IgG, because of either YFV vaccination or past exposure to various flaviviruses including YFV. Five cases were confirmed by FRNT50; of these, 4 were either vaccination or natural infection during the YF outbreak in 1992-1993 or another period and 1 case was confirmed as a West Nile virus infection. Domestication and routine performance of arboviral differential diagnosis will help to address the phenomenon of pyrexia of unknown origin, contribute to arboviral research in developing countries, and enhance regular surveillance.

  8. Localization and subcellular association of Grapevine Pinot Gris Virus in grapevine leaf tissues.

    Science.gov (United States)

    Tarquini, Giulia; Ermacora, Paolo; Bianchi, Gian Luca; De Amicis, Francesca; Pagliari, Laura; Martini, Marta; Loschi, Alberto; Saldarelli, Pasquale; Loi, Nazia; Musetti, Rita

    2018-05-01

    Despite the increasing impact of Grapevine Pinot gris disease (GPG-disease) worldwide, etiology about this disorder is still uncertain. The presence of the putative causal agent, the Grapevine Pinot Gris Virus (GPGV), has been reported in symptomatic grapevines (presenting stunting, chlorotic mottling, and leaf deformation) as well as in symptom-free plants. Moreover, information on virus localization in grapevine tissues and virus-plant interactions at the cytological level is missing at all. Ultrastructural and cytochemical investigations were undertaken to detect virus particles and the associated cytopathic effects in field-grown grapevine showing different symptom severity. Asymptomatic greenhouse-grown grapevines, which tested negative for GPGV by real time RT-PCR, were sampled as controls. Multiplex real-time RT-PCR and ELISA tests excluded the presence of viruses included in the Italian certification program both in field-grown and greenhouse-grown grapevines. Conversely, evidence was found for ubiquitous presence of Grapevine Rupestris Stem Pitting-associated Virus (GRSPaV), Hop Stunt Viroid (HSVd), and Grapevine Yellow Speckle Viroid 1 (GYSVd-1) in both plant groups. Moreover, in every field-grown grapevine, GPGV was detected by real-time RT-PCR. Ultrastructural observations and immunogold labelling assays showed filamentous flexuous viruses in the bundle sheath cells, often located inside membrane-bound organelles. No cytological differences were observed among field-grown grapevine samples showing different symptom severity. GPGV localization and associated ultrastructural modifications are reported and discussed, in the perspective of assisting management and control of the disease.

  9. Characterization of active-site residues of the NIa protease from tobacco vein mottling virus.

    Science.gov (United States)

    Hwang, D C; Kim, D H; Lee, J S; Kang, B H; Han, J; Kim, W; Song, B D; Choi, K Y

    2000-10-31

    Nuclear inclusion a (NIa) protease of tobacco vein mottling virus is responsible for the processing of the viral polyprotein into functional proteins. In order to identify the active-site residues of the TVMV NIa protease, the putative active-site residues, His-46, Asp-81 and Cys-151, were mutated individually to generate H46R, H46A, D81E, D81N, C151S, and C151A, and their mutational effects on the proteolytic activities were examined. Proteolytic activity was completely abolished by the mutations of H46R, H46A, D81N, and C151A, suggesting that the three residues are crucial for catalysis. The mutation of D81E decreased kcat marginally by about 4.7-fold and increased Km by about 8-fold, suggesting that the aspartic acid at position 81 is important for substrate binding but can be substituted by glutamate without any significant decrease in catalysis. The replacement of Cys-151 by Ser to mimic the catalytic triad of chymotrypsin-like serine protease resulted in the drastic decrease in kcat by about 1,260-fold. This result might be due to the difference of the active-site geometry between the NIa protease and chymotrypsin. The protease exhibited a bell-shaped pH-dependent profile with a maximum activity approximately at pH 8.3 and with the abrupt changes at the respective pKa values of approximately 6.6 and 9.2, implying the involvement of a histidine residue in catalysis. Taken together, these results demonstrate that the three residues, His-46, Asp-81, and Cys-151, play a crucial role in catalysis of the TVMV NIa protease.

  10. Barley yellow dwarf virus in barley crops in Tunisia: prevalence and molecular characterization

    OpenAIRE

    Asma NAJAR; Imen HAMDI; Arvind VARSANI

    2017-01-01

    A field survey was conducted in Tunisia in the North-Eastern regions (Bizerte, CapBon and Zaghouan), the North-Western region (Kef) and the Central-Eastern region (Kairouan) during the 2011/2012 growing season, in order to determine the incidence and the geographic distribution of Barley yellow dwarf virus (BYDVs) in barley fields. Tissue blot immunoassays (TBIA) showed that BYDV was most common in Zaghouan (incidence 14%), Cap Bon (14%) and Bizerte (35%), in randomly collected samples from t...

  11. Presence and characterization of Zucchini yellow mosaic virus in watermelon in Serbia

    Directory of Open Access Journals (Sweden)

    Vučurović Ana

    2012-01-01

    Full Text Available The presence of Zucchini yellow mosaic virus (ZYMV in two out of seven watermelon production localities in Serbia during 2011 was investigated by analyzing leaves sampled from symptomatic and asymptomatic watermelon plants and utilizing DAS-ELISA test. In the locality of Gornji Tavankut, ZYMV was detected in 23.08% of tested plants in single infections, and in the locality of Silbas it was detected in 35.29% of tested plants in mixed infections with Cucumber mosaic virus and Alfalfa mosaic virus. ZYMV was successfully mechanically transmitted from naturally infected watermelon plants to Cucurbita pepo 'Ezra F1'. Molecular detection was performed by RT-PCR and amplification of part of the gene for nuclear inclusions, gene of coat protein and part of 3' non-coding region, which confirmed the identification of the ZYMV isolates. Phylogenetic analysis revealed grouping of the isolate originating from watermelon with other isolates from Serbia and Central Europe within A-I subgroup. Analysis of amino acid sequences of the N terminal end of the CP gene revealed that isolate 550-11 belongs to the Central European branch.

  12. Climate Change and the Arboviruses: Lessons from the Evolution of the Dengue and Yellow Fever Viruses.

    Science.gov (United States)

    Tabachnick, Walter J

    2016-09-29

    The impact of anticipated changes in global climate on the arboviruses and the diseases they cause poses a significant challenge for public health. The past evolution of the dengue and yellow fever viruses provides clues about the influence of changes in climate on their future evolution. The evolution of both viruses has been influenced by virus interactions involving the mosquito species and the primate hosts involved in virus transmission, and by their domestic and sylvatic cycles. Information is needed on how viral genes in general influence phenotypic variance for important viral functions. Changes in global climate will alter the interactions of mosquito species with their primate hosts and with the viruses in domestic cycles, and greater attention should be paid to the sylvatic cycles. There is great danger for the evolution of novel viruses, such as new serotypes, that could compromise vaccination programs and jeopardize public health. It is essential to understand (a) both sylvatic and domestic cycles and (b) the role of virus genetic and environmental variances in shaping virus phenotypic variance to more fully assess the impact of global climate change.

  13. Two Crinivirus-specific proteins of Lettuce infectious yellows virus (LIYV), P26 and P9, are self-interacting.

    Science.gov (United States)

    Stewart, Lucy R; Hwang, Min Sook; Falk, Bryce W

    2009-11-01

    Interactions of Lettuce infectious yellows virus (LIYV)-encoded proteins were tested by yeast-two-hybrid (Y2H) assays. LIYV-encoded P34, Hsp70h, P59, CP, CPm, and P26 were tested in all possible pairwise combinations. Interaction was detected only for the P26-P26 combination. P26 self-interaction domains were mapped using a series of N- and C-terminal truncations. Orthologous P26 proteins from the criniviruses Beet pseudoyellows virus (BPYV), Cucurbit yellow stunting disorder virus (CYSDV), and Lettuce chlorosis virus (LCV) were also tested, and each exhibited strong self-interaction but no interaction with orthologous proteins. Two small putative proteins encoded by LIYV RNA2, P5 and P9, were also tested for interactions with the six aforementioned LIYV proteins and each other. No interactions were detected for P5, but P9-P9 self-interaction was detected. P26- and P9-encoding genes are present in all described members of the genus Crinivirus, but are not present in other members of the family Closteroviridae. LIYV P26 has previously been demonstrated to induce a unique LIYV cytopathology, plasmalemma deposits (PLDs), but no role is yet known for P9.

  14. Insights Into the Etiology of Polerovirus-Induced Pepper Yellows Disease.

    Science.gov (United States)

    Lotos, Leonidas; Olmos, Antonio; Orfanidou, Chrysoula; Efthimiou, Konstantinos; Avgelis, Apostolos; Katis, Nikolaos I; Maliogka, Varvara I

    2017-12-01

    The study of an emerging yellows disease of pepper crops (pepper yellows disease [PYD]) in Greece led to the identification of a polerovirus closely related to Pepper vein yellows virus (PeVYV). Recovery of its full genome sequence by next-generation sequencing of small interfering RNAs allowed its characterization as a new poleroviruses, which was provisionally named Pepper yellows virus (PeYV). Transmission experiments revealed its association with the disease. Sequence similarity and phylogenetic analysis highlighted the common ancestry of the three poleroviruses (PeVYV, PeYV, and Pepper yellow leaf curl virus [PYLCV]) currently reported to be associated with PYD, even though significant genetic differences were identified among them, especially in the C-terminal region of P5 and the 3' noncoding region. Most of the differences observed can be attributed to a modular type of evolution, which produces mosaic-like variants giving rise to these different poleroviruses Overall, similar to other polerovirus-related diseases, PYD is caused by at least three species (PeVYV, PeYV, and PYLCV) belonging to this group of closely related pepper-infecting viruses.

  15. Lettuce infectious yellows virus-encoded P26 induces plasmalemma deposit cytopathology

    International Nuclear Information System (INIS)

    Stewart, Lucy R.; Medina, Vicente; Sudarshana, Mysore R.; Falk, Bryce W.

    2009-01-01

    Lettuce infectious yellows virus (LIYV) encodes a 26 kDa protein (P26) previously shown to associate with plasmalemma deposits (PLDs), unique LIYV-induced cytopathologies located at the plasmalemma over plasmodesmata pit fields in companion cells and phloem parenchyma. To further characterize the relationship of P26 and PLDs, we assessed localization and cytopathology induction of P26 expressed from either LIYV or a heterologous Tobacco mosaic virus (TMV) vector using green fluorescent protein (GFP) fusions, immunofluorescence microscopy, biochemical fractionation, and transmission electron microscopy (TEM). TEM analyses demonstrated that P26 not only associated with, but induced formation of PLDs in the absence of other LIYV proteins. Interestingly, PLDs induced by P26-expressing TMV were no longer confined to phloem cells. Putative P26 orthologs from two other members of the genus Crinivirus which do not induce conspicuous PLDs exhibited fractionation properties similar to LIYV P26 but were not associated with any PLD-like cytopathology.

  16. Tomato yellow leaf curl virus can be acquired and transmitted by Bemisia tabaci (Gennadius) from tomato fruits

    NARCIS (Netherlands)

    Delatte, H.; Dalmon, A.; Rist, D.; Soustrade, I.; Wuster, G.; Lett, J.M.; Goldbach, R.W.; Peterschmitt, M.; Reynaud, B.

    2003-01-01

    The whitefly Bemisia tabaci is an insect pest causing worldwide economic losses, especially as a vector of geminiviruses such as Tomato yellow leaf curl virus (TYLCV). Currently, imported and exported tomato fruit are not monitored for TYLCV infection because they are not considered to represent a

  17. STUDIES ON SOUTH AMERICAN YELLOW FEVER

    Science.gov (United States)

    Davis, Nelson C.; Shannon, Raymond C.

    1929-01-01

    Yellow fever virus from M. rhesus has been inoculated into a South American monkey (Cebus macrocephalus) by blood injection and by bites of infected mosquitoes. The Cebus does not develop the clinical or pathological signs of yellow fever. Nevertheless, the virus persists in the Cebus for a time as shown by the typical symptoms and lesions which develop when the susceptible M. rhesus is inoculated from a Cebus by direct transfer of blood or by mosquito (A. aegypti) transmission. PMID:19869607

  18. Analysis of sequences from field samples reveals the presence of the recently described pepper vein yellows virus (genus Polerovirus) in six additional countries.

    Science.gov (United States)

    Knierim, Dennis; Tsai, Wen-Shi; Kenyon, Lawrence

    2013-06-01

    Polerovirus infection was detected by reverse transcription polymerase chain reaction (RT-PCR) in 29 pepper plants (Capsicum spp.) and one black nightshade plant (Solanum nigrum) sample collected from fields in India, Indonesia, Mali, Philippines, Thailand and Taiwan. At least two representative samples for each country were selected to generate a general polerovirus RT-PCR product of 1.4 kb length for sequencing. Sequence analysis of the partial genome sequences revealed the presence of pepper vein yellows virus (PeVYV) in all 13 samples. A 1990 Australian herbarium sample of pepper described by serological means as infected with capsicum yellows virus (CYV) was identified by sequence analysis of a partial CP sequence as probably infected with a potato leaf roll virus (PLRV) isolate.

  19. Inheritance of resistance to barley yellow dwarf virus detected by northern blot analysis

    International Nuclear Information System (INIS)

    Lorens, G.F.; Falk, B.W.; Qualset, C.O.

    1989-01-01

    Development of wheat (Triticum aestivum L.) cultivars tolerant to the barley yellow dwarf virus disease (BYD) has been limited by lack of precision in rating plants for response to infection, usually done by visual scoring of plant symptoms under field conditions. Other methodologies have been developed to study the host/pathogen relationship and to assess resistance or susceptibility. In this study northern dot blot analysis was used to determine barley yellow dwarf virus (BYDV) RNA concentrations of six wheat cultivars that differed in visual BYD symptom expression. Plants were infected with the NYPAV (PAV) isolate of BYDV in the greenhouse. At several dates after inoculation crude plant extracts were blotted on nitrocellulose and hybridized with a 32 P-labeled probe of the pPA8 cDNA clone of BYDV. The distribution of PRC for the F 2 population was compared to the distribution of BYD visual symptom scores for 403 F 2 plants of a similar F 2 population of NS 879/4 x Seri 82 under field conditions. The results were qualitatively similar, suggesting that northern dot blot analysis to measure PRC may be useful in understanding the genetics of resistance to BYD. This technique, when incorporated into breeding programs, could be important in the development of highly tolerant wheat cultivars with reduced losses to BYD

  20. Virus-induced gene silencing in Medicago truncatula and Lathyrus odorata

    DEFF Research Database (Denmark)

    Grønlund, Mette; Kjær, Gabriela Didina Constantin; Piednoir, Elodie

    2008-01-01

    Virus-induced gene silencing (VIGS) has become an important reverse genetics tool for functional genomics. VIGS vectors based on Pea early browning virus (PEBV, genus Tobravirus) and Bean pod mottle virus (genus Comovirus) are available for the legume species Pisum sativum and Glycine max, respec...

  1. Prevalence and titers of yellow fever virus neutralizing antibodies in previously vaccinated adults.

    Science.gov (United States)

    Miyaji, Karina Takesaki; Avelino-Silva, Vivian Iida; Simões, Marisol; Freire, Marcos da Silva; Medeiros, Carlos Roberto de; Braga, Patrícia Emilia; Neves, Maria Angélica Acalá; Lopes, Marta Heloisa; Kallas, Esper Georges; Sartori, Ana Marli Christovam

    2017-04-03

    The World Health Organization (WHO) recommends one single dose of the Yellow Fever (YF) vaccine based on studies of antibody persistency in healthy adults. We assessed the prevalence and titers of YF virus neutralizing antibodies in previously vaccinated persons aged  60 years, in comparison to younger adults. We also evaluated the correlation between antibody titers and the time since vaccination among participants who received one vaccine dose, and the seropositivity among participants vaccinated prior to or within the past 10 years. previously vaccinated healthy persons aged  18 years were included. YF virus neutralizing antibody titers were determined by means of the 50% Plaque Reduction Neutralization Test. 46 persons aged  60 years and 48 persons aged 18 to 59 years were enrolled. There was no significant difference in the prevalence of YF virus neutralizing antibodies between the two groups (p = 0.263). However, titers were significantly lower in the elderly (p = 0.022). There was no correlation between YF virus neutralizing antibody titers and the time since vaccination. There was no significant difference in seropositivity among participants vaccinated prior to or within the past 10 years. the clinical relevance of the observed difference in YF virus neutralizing antibody titers between the two groups is not clear.

  2. A protein kinase binds the C-terminal domain of the readthrough protein of Turnip yellows virus and regulates virus accumulation

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez-Medina, Caren; Boissinot, Sylvaine [UMR 1131 SVQV INRA-UDS, 28 rue de Herrlisheim, 68021 Colmar (France); Chapuis, Sophie [Institut de Biologie Moléculaire des Plantes, Laboratoire propre du CNRS conventionné avec l’Université de Strasbourg, 12 rue du Général Zimmer, 67084 Strasbourg (France); Gereige, Dalya; Rastegar, Maryam; Erdinger, Monique [UMR 1131 SVQV INRA-UDS, 28 rue de Herrlisheim, 68021 Colmar (France); Revers, Frédéric [INRA, Université de Bordeaux, UMR 1332 de Biologie du Fruit et Pathologie, 33882 Villenave d’Ornon (France); Ziegler-Graff, Véronique [Institut de Biologie Moléculaire des Plantes, Laboratoire propre du CNRS conventionné avec l’Université de Strasbourg, 12 rue du Général Zimmer, 67084 Strasbourg (France); Brault, Véronique, E-mail: veronique.brault@colmar.inra.fr [UMR 1131 SVQV INRA-UDS, 28 rue de Herrlisheim, 68021 Colmar (France)

    2015-12-15

    Turnip yellows virus (TuYV), a phloem-limited virus, encodes a 74 kDa protein known as the readthrough protein (RT) involved in virus movement. We show here that a TuYV mutant deleted of the C-terminal part of the RT protein (TuYV-∆RT{sub Cter}) was affected in long-distance trafficking in a host-specific manner. By using the C-terminal domain of the RT protein as a bait in a yeast two-hybrid screen of a phloem cDNA library from Arabidopsis thaliana we identified the calcineurin B-like protein-interacting protein kinase-7 (AtCIPK7). Transient expression of a GFP:CIPK7 fusion protein in virus-inoculated Nicotiana benthamiana leaves led to local increase of wild-type TuYV accumulation, but not that of TuYV-∆RT{sub Cter}. Surprisingly, elevated virus titer in inoculated leaves did not result in higher TuYV accumulation in systemic leaves, which indicates that virus long-distance movement was not affected. Since GFP:CIPK7 was localized in or near plasmodesmata, CIPK7 could negatively regulate TuYV export from infected cells. - Highlights: • The C-terminal domain of TuYV-RT is required for long-distance movement. • CIPK7 from Arabidopsis interacts with RT{sub Cter} in yeast and in plants. • CIPK7 overexpression increases virus titer locally but not virus systemic movement. • CIPK7 localizes to plasmodesmata. • CIPK7 could be a defense protein regulating virus export.

  3. Molecular phylogeny of edge hill virus supports its position in the yellow Fever virus group and identifies a new genetic variant.

    Science.gov (United States)

    Macdonald, Joanne; Poidinger, Michael; Mackenzie, John S; Russell, Richard C; Doggett, Stephen; Broom, Annette K; Phillips, Debra; Potamski, Joseph; Gard, Geoff; Whelan, Peter; Weir, Richard; Young, Paul R; Gendle, Debra; Maher, Sheryl; Barnard, Ross T; Hall, Roy A

    2010-06-15

    Edge Hill virus (EHV) is a mosquito-borne flavivirus isolated throughout Australia during mosquito surveillance programs. While not posing an immediate threat to the human population, EHV is a taxonomically interesting flavivirus since it remains the only member of the yellow fever virus (YFV) sub-group to be detected within Australia. Here we present both an antigenic and genetic investigation of collected isolates, and confirm taxonomic classification of the virus within the YFV-group. Isolates were not clustered based on geographical origin or time of isolation, suggesting that minimal genetic evolution of EHV has occurred over geographic distance or time within the EHV cluster. However, two isolates showed significant differences in antigenic reactivity patterns, and had a much larger divergence from the EHV prototype (19% nucleotide and 6% amino acid divergence), indicating a distinct subtype or variant within the EHV subgroup.

  4. Influence of the surface roughness of coated and uncoated papers on the digital print mottle

    Directory of Open Access Journals (Sweden)

    Ivana Jurič

    2014-07-01

    Full Text Available Many factors influence the occurrence of print mottle in prints. In printing process three main components are involved: printing press, substrate and toner. They can be considered as separate components, but in most cases their interaction influences the quality of the print. The goal of this work was to examine the influence of surface roughness of different types of paper (coated and uncoated on print mottle of electrophotographic digital prints. We set up a hypothesis that print mottle will be more apparent on rougher surfaces. In the experimental part we printed four different substrates with different surface properties on electrophotographic printing press. Morphology of the papers surface was analysed using atomic force microscopy (AFM from which surface properties were calculated. For print mottle characterization Gray level co-occurrence matrix (GLCM method was used. Based on the measurements and results we can conclude, contrary to the initial hypothesis, that uncoated papers with rougher surfaces produce smaller print mottle values.

  5. Detection of new viruses in alfalfa, weeds and cultivated plants growing adjacent to alfalfa fields in Saudi Arabia.

    Science.gov (United States)

    Al-Shahwan, I M; Abdalla, O A; Al-Saleh, M A; Amer, M A

    2017-09-01

    A total of 1368 symptomatic plant samples showing different virus-like symptoms such as mottling, chlorosis, mosaic, yellow mosaic, vein clearing and stunting were collected from alfalfa, weed and cultivated plant species growing in vicinity of alfalfa fields in five principal regions of alfalfa production in Saudi Arabia. DAS-ELISA test indicated occurrence of 11 different viruses in these samples, 10 of which were detected for the first time in Saudi Arabia. Eighty percent of the alfalfa samples and 97.5% of the weed and cultivated plants samples were found to be infected with one or more of these viruses. Nine weed plant species were found to harbor these viruses namely, Sonchus oleraceus, Chenopodium spp., Hibiscus spp., Cichorium intybus , Convolvulus arvensis , Malva parviflora , Rubus fruticosus , Hippuris vulgaris , and Flaveria trinervia . These viruses were also detected in seven cultivated crop plants growing adjacent to the alfalfa fields including Vigna unguiculata , Solanum tuberosum , Solanum melongena , Phaseolus vulgaris , Cucurbita maxima , Capsicum annuum , and Vicia faba . The newly reported viruses together with their respective percent of detection in alfalfa, and in both weeds and cultivated crop plant species together were as follows: Bean leaf roll virus (BLRV) {12.5 and 4.5%}, Lucerne transient streak virus (LTSV) {2.9 and 3.5%}, Bean yellow mosaic virus (BYMV) {1.4 and 4.5%}, Bean common mosaic virus (BCMV) {1.2 and 4.5%}, Red clover vein mosaic virus (RCVMV) {1.2 and 4%}, White clover mosaic virus (WCIMV) {1.0 and 5%}, Cucumber mosaic virus (CMV) {0.8 and 3%}, Pea streak virus (PeSV) {0.4 and 4.5%} and Tobacco streak virus (TSV) {0.3 and 2.5%}. Alfalfa mosaic virus (AMV), the previously reported virus in alfalfa, had the highest percentage of detection in alfalfa accounting for 58.4% and 62.8% in the weeds and cultivated plants. Peanut stunt virus (PSV) was also detected for the first time in Saudi Arabia with a 66.7% of infection in 90

  6. Detection of new viruses in alfalfa, weeds and cultivated plants growing adjacent to alfalfa fields in Saudi Arabia

    Directory of Open Access Journals (Sweden)

    I.M. Al-Shahwan

    2017-09-01

    Full Text Available A total of 1368 symptomatic plant samples showing different virus-like symptoms such as mottling, chlorosis, mosaic, yellow mosaic, vein clearing and stunting were collected from alfalfa, weed and cultivated plant species growing in vicinity of alfalfa fields in five principal regions of alfalfa production in Saudi Arabia. DAS-ELISA test indicated occurrence of 11 different viruses in these samples, 10 of which were detected for the first time in Saudi Arabia. Eighty percent of the alfalfa samples and 97.5% of the weed and cultivated plants samples were found to be infected with one or more of these viruses. Nine weed plant species were found to harbor these viruses namely, Sonchus oleraceus, Chenopodium spp., Hibiscus spp., Cichorium intybus, Convolvulus arvensis, Malva parviflora, Rubus fruticosus, Hippuris vulgaris, and Flaveria trinervia. These viruses were also detected in seven cultivated crop plants growing adjacent to the alfalfa fields including Vigna unguiculata, Solanum tuberosum, Solanum melongena, Phaseolus vulgaris, Cucurbita maxima, Capsicum annuum, and Vicia faba. The newly reported viruses together with their respective percent of detection in alfalfa, and in both weeds and cultivated crop plant species together were as follows: Bean leaf roll virus (BLRV {12.5 and 4.5%}, Lucerne transient streak virus (LTSV {2.9 and 3.5%}, Bean yellow mosaic virus (BYMV {1.4 and 4.5%}, Bean common mosaic virus (BCMV {1.2 and 4.5%}, Red clover vein mosaic virus (RCVMV {1.2 and 4%}, White clover mosaic virus (WCIMV {1.0 and 5%}, Cucumber mosaic virus (CMV {0.8 and 3%}, Pea streak virus (PeSV {0.4 and 4.5%} and Tobacco streak virus (TSV {0.3 and 2.5%}. Alfalfa mosaic virus (AMV, the previously reported virus in alfalfa, had the highest percentage of detection in alfalfa accounting for 58.4% and 62.8% in the weeds and cultivated plants. Peanut stunt virus (PSV was also detected for the first time in Saudi Arabia with a 66.7% of infection in 90

  7. The yellow fever 17D virus as a platform for new live attenuated vaccines.

    Science.gov (United States)

    Bonaldo, Myrna C; Sequeira, Patrícia C; Galler, Ricardo

    2014-01-01

    The live-attenuated yellow fever 17D virus is one of the most outstanding human vaccines ever developed. It induces efficacious immune responses at a low production cost with a well-established manufacture process. These advantages make the YF17D virus attractive as a vector for the development of new vaccines. At the beginning of vector development studies, YF17D was genetically manipulated to express other flavivirus prM and E proteins, components of the viral envelope. While these 17D recombinants are based on the substitution of equivalent YF17D genes, other antigens from unrelated pathogens have also been successfully expressed and delivered by recombinant YF17D viruses employing alternative strategies for genetic manipulation of the YF17D genome. Herein, we discuss these strategies in terms of possibilities of single epitope or larger sequence expression and the main properties of these replication-competent viral platforms.

  8. The giant mottled eel, Anguilla marmorata, uses blue-shifted rod photoreceptors during upstream migration.

    Science.gov (United States)

    Wang, Feng-Yu; Fu, Wen-Chun; Wang, I-Li; Yan, Hong Young; Wang, Tzi-Yuan

    2014-01-01

    Catadromous fishes migrate between ocean and freshwater during particular phases of their life cycle. The dramatic environmental changes shape their physiological features, e.g. visual sensitivity, olfactory ability, and salinity tolerance. Anguilla marmorata, a catadromous eel, migrates upstream on dark nights, following the lunar cycle. Such behavior may be correlated with ontogenetic changes in sensory systems. Therefore, this study was designed to identify changes in spectral sensitivity and opsin gene expression of A. marmorata during upstream migration. Microspectrophotometry analysis revealed that the tropical eel possesses a duplex retina with rod and cone photoreceptors. The λmax of rod cells are 493, 489, and 489 nm in glass, yellow, and wild eels, while those of cone cells are 508, and 517 nm in yellow, and wild eels, respectively. Unlike European and American eels, Asian eels exhibited a blue-shifted pattern of rod photoreceptors during upstream migration. Quantitative gene expression analyses of four cloned opsin genes (Rh1f, Rh1d, Rh2, and SWS2) revealed that Rh1f expression is dominant at all three stages, while Rh1d is expressed only in older yellow eel. Furthermore, sequence comparison and protein modeling studies implied that a blue shift in Rh1d opsin may be induced by two known (N83, S292) and four putative (S124, V189, V286, I290) tuning sites adjacent to the retinal binding sites. Finally, expression of blue-shifted Rh1d opsin resulted in a spectral shift in rod photoreceptors. Our observations indicate that the giant mottled eel is color-blind, and its blue-shifted scotopic vision may influence its upstream migration behavior and habitat choice.

  9. The community ecology of barley/cereal yellow dwarf viruses in Western US grasslands.

    Science.gov (United States)

    Power, Alison G; Borer, Elizabeth T; Hosseini, Parviez; Mitchell, Charles E; Seabloom, Eric W

    2011-08-01

    Research on plant viruses in natural ecosystems has been increasing rapidly over the past decade. This paper reviews recent research on the barley and cereal yellow dwarf viruses (B/CYDVs) in grasslands of the western US, beginning with the evidence that the disease caused by these viruses facilitated the invasion of western US grasslands by European annual grasses. Observational and experimental studies of B/CYDVs were carried out along a latitudinal gradient (33.8-48.8°N) from southern California to southern Canada. The prevalence and community composition of B/CYDVs were assessed over a variety of scales and under a range of biotic and abiotic conditions. The findings indicate that both biotic and abiotic factors are important influences on virus ecology and epidemiology. Introduced annual grasses are high-quality hosts that amplify both virus and vector populations in this system, but our research suggests that endemic perennial grasses are critically important for sustaining virus populations in contemporary grasslands largely composed of introduced species. Experiments indicated that increased phosphorus supply to hosts resulted in greater host biomass and higher virus prevalence. Using experimental exclosures, it was found that the presence of grazing vertebrate herbivores increased the abundance of annual grasses, resulting in increased virus prevalence. The results of these studies suggest that patterns of B/CYDV prevalence and coinfection in western US grasslands are strongly shaped by the interactions of host plants, vectors, vertebrate herbivores, and abiotic drivers including nutrients. Copyright © 2011 Elsevier B.V. All rights reserved.

  10. Engineering resistance against Tomato yellow leaf curl virus via the CRISPR/Cas9 system in tomato

    KAUST Repository

    Mahfouz, Magdy M.

    2017-12-22

    CRISPR/Cas systems confer molecular immunity against phages and conjugative plasmids in prokaryotes. Recently, CRISPR/Cas9 systems have been used to confer interference against eukaryotic viruses. Here, we engineered Nicotiana benthamiana and tomato (Solanum lycopersicum) plants with the CRISPR/Cas9 system to confer immunity against the Tomato yellow leaf curl virus (TYLCV). Targeting the TYLCV genome with Cas9-single guide RNA at the sequences encoding the coat protein (CP) or replicase (Rep) resulted in efficient virus interference, as evidenced by low accumulation of the TYLCV DNA genome in the transgenic plants. The CRISPR/Cas9-based immunity remained active across multiple generations in the N. benthamiana and tomato plants. Together, our results confirmed the efficiency of the CRISPR/Cas9 system for stable engineering of TYLCV resistance in N. benthamiana and tomato, and opens the possibilities of engineering virus resistance against single and multiple infectious viruses in other crops.

  11. Changes induced by the Pepper mild mottle tobamovirus on the chloroplast proteome of Nicotiana benthamiana.

    Science.gov (United States)

    Pineda, M; Sajnani, C; Barón, M

    2010-01-01

    We have analyzed the chloroplast proteome of Nicotiana benthamiana using two-dimensional gel electrophoresis and mass spectrometry followed by a database search. In order to improve the resolution of the two-dimensional electrophoresis gels, we have made separate maps for the low and the high pH range. At least 200 spots were detected. We identified 72 polypeptides, some being isoforms of different multiprotein families. In addition, changes in this chloroplast proteome induced by the infection with the Spanish strain of the Pepper mild mottle virus were investigated. Viral infection induced the down-regulation of several chloroplastidic proteins involved in both the photosynthetic electron-transport chain and the Benson-Calvin cycle.

  12. Fatal Yellow Fever in Travelers to Brazil, 2018.

    Science.gov (United States)

    Hamer, Davidson H; Angelo, Kristina; Caumes, Eric; van Genderen, Perry J J; Florescu, Simin A; Popescu, Corneliu P; Perret, Cecilia; McBride, Angela; Checkley, Anna; Ryan, Jenny; Cetron, Martin; Schlagenhauf, Patricia

    2018-03-23

    Yellow fever virus is a mosquito-borne flavivirus that causes yellow fever, an acute infectious disease that occurs in South America and sub-Saharan Africa. Most patients with yellow fever are asymptomatic, but among the 15% who develop severe illness, the case fatality rate is 20%-60%. Effective live-attenuated virus vaccines are available that protect against yellow fever (1). An outbreak of yellow fever began in Brazil in December 2016; since July 2017, cases in both humans and nonhuman primates have been reported from the states of São Paulo, Minas Gerais, and Rio de Janeiro, including cases occurring near large urban centers in these states (2). On January 16, 2018, the World Health Organization updated yellow fever vaccination recommendations for Brazil to include all persons traveling to or living in Espírito Santo, São Paulo, and Rio de Janeiro states, and certain cities in Bahia state, in addition to areas where vaccination had been recommended before the recent outbreak (3). Since January 2018, 10 travel-related cases of yellow fever, including four deaths, have been reported in international travelers returning from Brazil. None of the 10 travelers had received yellow fever vaccination.

  13. Cooking and Eating Quality of Rice Yellow Mottle Virus Resistant ...

    African Journals Online (AJOL)

    The study was conducted to evaluate the cooking and eating quality of mutant lines obtained from irradiating a local cultivar, Supa. Five early maturing mutant lines plus two controls, IR! 53234-27-1 and Supa were evaluated for their physical grain characteristics including length and shape of grain kernel, translucence and ...

  14. Yellow fever: an update.

    Science.gov (United States)

    Monath, T P

    2001-08-01

    Yellow fever, the original viral haemorrhagic fever, was one of the most feared lethal diseases before the development of an effective vaccine. Today the disease still affects as many as 200,000 persons annually in tropical regions of Africa and South America, and poses a significant hazard to unvaccinated travellers to these areas. Yellow fever is transmitted in a cycle involving monkeys and mosquitoes, but human beings can also serve as the viraemic host for mosquito infection. Recent increases in the density and distribution of the urban mosquito vector, Aedes aegypti, as well as the rise in air travel increase the risk of introduction and spread of yellow fever to North and Central America, the Caribbean and Asia. Here I review the clinical features of the disease, its pathogenesis and pathophysiology. The disease mechanisms are poorly understood and have not been the subject of modern clinical research. Since there is no specific treatment, and management of patients with the disease is extremely problematic, the emphasis is on preventative vaccination. As a zoonosis, yellow fever cannot be eradicated, but reduction of the human disease burden is achievable through routine childhood vaccination in endemic countries, with a low cost for the benefits obtained. The biological characteristics, safety, and efficacy of live attenuated, yellow fever 17D vaccine are reviewed. New applications of yellow fever 17D virus as a vector for foreign genes hold considerable promise as a means of developing new vaccines against other viruses, and possibly against cancers.

  15. Blood lead exposure concentrations in mottled ducks (Anas fulvigula) on the upper Texas coast

    Science.gov (United States)

    McDowell, Stephen K.; Conway, Warren C.; Haukos, David A.; Moon, Jena A.; Comer, Christopher E.; Hung, I-Kuai

    2015-01-01

    The mottled duck (Anas fulvigula) is a non-migratory waterfowl species dependent upon coastal marsh systems, including those on the Texas Chenier Plain National Wildlife Refuge (NWR) Complex, and considered a regional indicator species of marsh habitat quality. Research from the early 1970s, 1990s, and early-2000s indicated that mottled ducks continued to exhibit elevated wing-bone lead (Pb) concentrations, decades after implementation of non-toxic shot regulations. However, wing-bone concentrations reflect lifetime accumulation of Pb, whereas blood Pb concentrations reflect more recent exposure. To identify current potentially relevant temporal windows of Pb exposure, we collected 260 blood samples from mottled ducks during summer (n=124) and winter (n=136) from 2010–2012 on the Texas Chenier Plain NWR Complex. We quantified baseline blood Pb concentrations for all ages of mottled ducks, and hypothesized that blood lead concentrations would remain elevated above background levels (200 µg L–1) despite the 1983 and 1991 lead shot bans. Blood Pb concentrations ranged from below detection limits to >12,000 µg L–1, where >200 µg L–1 was associated with exposure levels above background concentrations. Male mottled ducks had the greatest blood Pb concentrations (30 times greater than females) with concentrations greater during winter than summer. Likewise, the proportion of exposed (>200 µg L–1) females increased from 14%–47% from summer to winter, respectively. Regardless of sex, adult mottled duck blood Pb concentrations were five times greater than juveniles, particularly during winter. We identified five plausible models that influenced blood Pb levels where year, site, and interactions among age*sex*season and between age*season were included in the top-ranked models. Frequency of exposure was greatest during winter, increasing from 12% in summer to 55% in winter, indicating that a temporal exposure window to environmental Pb exists between nesting

  16. Identification of Cleavage Sites Recognized by the 3C-Like Cysteine Protease within the Two Polyproteins of Strawberry Mottle Virus

    Directory of Open Access Journals (Sweden)

    Hélène Sanfaçon

    2017-04-01

    Full Text Available Strawberry mottle virus (SMoV, family Secoviridae, order Picornavirales is one of several viruses found in association with strawberry decline disease in Eastern Canada. The SMoV genome consists of two positive-sense single-stranded RNAs, each encoding one large polyprotein. The RNA1 polyprotein (P1 includes the domains for a putative helicase, a VPg, a 3C-like cysteine protease and an RNA-dependent RNA polymerase at its C-terminus, and one or two protein domains at its N-terminus. The RNA2 polyprotein (P2 is predicted to contain the domains for a movement protein (MP and one or several coat proteins at its N-terminus, and one or more additional domains for proteins of unknown function at its C-terminus. The RNA1-encoded 3C-like protease is presumed to cleave the two polyproteins in cis (P1 and in trans (P2. Using in vitro processing assays, we systematically scanned the two polyproteins for cleavage sites recognized by this protease. We identified five cis-cleavage sites in P1, with cleavage between the putative helicase and VPg domains being the most efficient. The presence of six protein domains in the SMoV P1, including two upstream of the putative helicase domain, is a feature shared with nepoviruses but not with comoviruses. Results from trans-cleavage assays indicate that the RNA1-encoded 3C-like protease recognized a single cleavage site, which was between the predicted MP and coat protein domains in the P2 polyprotein. The cleavage site consensus sequence for the SMoV 3C-like protease is AxE (E or Q/(G or S.

  17. Biological and phylogenetic characteristics of yellow fever virus lineages from West Africa.

    Science.gov (United States)

    Stock, Nina K; Laraway, Hewád; Faye, Ousmane; Diallo, Mawlouth; Niedrig, Matthias; Sall, Amadou A

    2013-03-01

    The yellow fever virus (YFV), the first proven human-pathogenic virus, although isolated in 1927, is still a major public health problem, especially in West Africa where it causes outbreaks every year. Nevertheless, little is known about its genetic diversity and evolutionary dynamics, mainly due to a limited number of genomic sequences from wild virus isolates. In this study, we analyzed the phylogenetic relationships of 24 full-length genomes from YFV strains isolated between 1973 and 2005 in a sylvatic context of West Africa, including 14 isolates that had previously not been sequenced. By this, we confirmed genetic variability within one genotype by the identification of various YF lineages circulating in West Africa. Further analyses of the biological properties of these lineages revealed differential growth behavior in human liver and insect cells, correlating with the source of isolation and suggesting host adaptation. For one lineage, repeatedly isolated in a context of vertical transmission, specific characteristics in the growth behavior and unique mutations of the viral genome were observed and deserve further investigation to gain insight into mechanisms involved in YFV emergence and maintenance in nature.

  18. Coinfection with Hepatozoon sp. and Canine Distemper Virus in a Yellow-throated Marten ( Martes flavigula koreana) in Korea.

    Science.gov (United States)

    Park, Surim; Choi, Ul Soo; Kim, Eun Ju; Lee, Jong Hyun; Lee, Hae Beom; Cho, Ho Seong; Kim, Wonil; Lim, Chae Woong; Kim, Bumseok

    2016-04-28

    We describe coinfection with Hepatozoon sp. and canine distemper virus (CDV) in a yellow-throated marten ( Martes flavigula koreana). We found Hepatozoon cysts in muscular tissue and viral inclusion bodies in the brain. Hepatozoon sp., and CDV was confirmed in blood and brain, respectively, by PCR.

  19. A protein kinase binds the C-terminal domain of the readthrough protein of Turnip yellows virus and regulates virus accumulation

    International Nuclear Information System (INIS)

    Rodriguez-Medina, Caren; Boissinot, Sylvaine; Chapuis, Sophie; Gereige, Dalya; Rastegar, Maryam; Erdinger, Monique; Revers, Frédéric; Ziegler-Graff, Véronique; Brault, Véronique

    2015-01-01

    Turnip yellows virus (TuYV), a phloem-limited virus, encodes a 74 kDa protein known as the readthrough protein (RT) involved in virus movement. We show here that a TuYV mutant deleted of the C-terminal part of the RT protein (TuYV-∆RT_C_t_e_r) was affected in long-distance trafficking in a host-specific manner. By using the C-terminal domain of the RT protein as a bait in a yeast two-hybrid screen of a phloem cDNA library from Arabidopsis thaliana we identified the calcineurin B-like protein-interacting protein kinase-7 (AtCIPK7). Transient expression of a GFP:CIPK7 fusion protein in virus-inoculated Nicotiana benthamiana leaves led to local increase of wild-type TuYV accumulation, but not that of TuYV-∆RT_C_t_e_r. Surprisingly, elevated virus titer in inoculated leaves did not result in higher TuYV accumulation in systemic leaves, which indicates that virus long-distance movement was not affected. Since GFP:CIPK7 was localized in or near plasmodesmata, CIPK7 could negatively regulate TuYV export from infected cells. - Highlights: • The C-terminal domain of TuYV-RT is required for long-distance movement. • CIPK7 from Arabidopsis interacts with RT_C_t_e_r in yeast and in plants. • CIPK7 overexpression increases virus titer locally but not virus systemic movement. • CIPK7 localizes to plasmodesmata. • CIPK7 could be a defense protein regulating virus export.

  20. Molecular Phylogeny of Edge Hill Virus Supports its Position in the Yellow Fever Virus Group and Identifies a New Genetic Variant

    Directory of Open Access Journals (Sweden)

    Joanne Macdonald

    2010-06-01

    Full Text Available Edge Hill virus (EHV is a mosquito-borne flavivirus isolated throughout Australia during mosquito surveillance programs. While not posing an immediate threat to the human population, EHV is a taxonomically interesting flavivirus since it remains the only member of the yellow fever virus (YFV sub-group to be detected within Australia. Here we present both an antigenic and genetic investigation of collected isolates, and confirm taxonomic classification of the virus within the YFV-group. Isolates were not clustered based on geographical origin or time of isolation, suggesting that minimal genetic evolution of EHV has occurred over geographic distance or time within the EHV cluster. However, two isolates showed significant differences in antigenic reactivity patterns, and had a much larger divergence from the EHV prototype (19% nucleotide and 6% amino acid divergence, indicating a distinct subtype or variant within the EHV subgroup.

  1. Yellow Fever 17DD Vaccine Virus Infection Causes Detectable Changes in Chicken Embryos.

    Science.gov (United States)

    Manso, Pedro Paulo de Abreu; Dias de Oliveira, Barbara C E P; de Sequeira, Patrícia Carvalho; Maia de Souza, Yuli Rodrigues; Ferro, Jessica Maria dos Santos; da Silva, Igor José; Caputo, Luzia Fátima Gonçalves; Guedes, Priscila Tavares; dos Santos, Alexandre Araujo Cunha; Freire, Marcos da Silva; Bonaldo, Myrna Cristina; Pelajo-Machado, Marcelo

    2015-01-01

    The yellow fever (YF) 17D vaccine is one of the most effective human vaccines ever created. The YF vaccine has been produced since 1937 in embryonated chicken eggs inoculated with the YF 17D virus. Yet, little information is available about the infection mechanism of YF 17DD virus in this biological model. To better understand this mechanism, we infected embryos of Gallus gallus domesticus and analyzed their histopathology after 72 hours of YF infection. Some embryos showed few apoptotic bodies in infected tissues, suggesting mild focal infection processes. Confocal and super-resolution microscopic analysis allowed us to identify as targets of viral infection: skeletal muscle cells, cardiomyocytes, nervous system cells, renal tubular epithelium, lung parenchyma, and fibroblasts associated with connective tissue in the perichondrium and dermis. The virus replication was heaviest in muscle tissues. In all of these specimens, RT-PCR methods confirmed the presence of replicative intermediate and genomic YF RNA. This clearer characterization of cell targets in chicken embryos paves the way for future development of a new YF vaccine based on a new cell culture system.

  2. Yellow Fever 17DD Vaccine Virus Infection Causes Detectable Changes in Chicken Embryos

    Science.gov (United States)

    Manso, Pedro Paulo de Abreu; Dias de Oliveira, Barbara C. E. P.; de Sequeira, Patrícia Carvalho; Maia de Souza, Yuli Rodrigues; Ferro, Jessica Maria dos Santos; da Silva, Igor José; Caputo, Luzia Fátima Gonçalves; Guedes, Priscila Tavares; dos Santos, Alexandre Araujo Cunha; Freire, Marcos da Silva; Bonaldo, Myrna Cristina; Pelajo-Machado, Marcelo

    2015-01-01

    The yellow fever (YF) 17D vaccine is one of the most effective human vaccines ever created. The YF vaccine has been produced since 1937 in embryonated chicken eggs inoculated with the YF 17D virus. Yet, little information is available about the infection mechanism of YF 17DD virus in this biological model. To better understand this mechanism, we infected embryos of Gallus gallus domesticus and analyzed their histopathology after 72 hours of YF infection. Some embryos showed few apoptotic bodies in infected tissues, suggesting mild focal infection processes. Confocal and super-resolution microscopic analysis allowed us to identify as targets of viral infection: skeletal muscle cells, cardiomyocytes, nervous system cells, renal tubular epithelium, lung parenchyma, and fibroblasts associated with connective tissue in the perichondrium and dermis. The virus replication was heaviest in muscle tissues. In all of these specimens, RT-PCR methods confirmed the presence of replicative intermediate and genomic YF RNA. This clearer characterization of cell targets in chicken embryos paves the way for future development of a new YF vaccine based on a new cell culture system. PMID:26371874

  3. Antigenic variants of yellow fever virus with an altered neurovirulence phenotype in mice.

    Science.gov (United States)

    Ryman, K D; Xie, H; Ledger, T N; Campbell, G A; Barrett, A D

    1997-04-14

    The live-attenuated yellow fever (YF) vaccine virus, strain 17D-204, has long been known to consist of a heterologous population of virions. Gould et al. (J. Gen. Virol. 70, 1889-1894 (1989)) previously demonstrated that variant viruses exhibiting a YF wild-type-specific envelope (E) protein epitope are present at low frequency in the vaccine pool and were able to isolate representative virus variants with and without this epitope, designated 17D(+wt) and 17D(-wt), respectively. These variants were employed here in an investigation of YF virus pathogenesis in the mouse model. Both the 17D-204 parent and the 17D(+wt) variant viruses were lethal for adult outbred mice by the intracerebral route of inoculation. However, the 17D(-wt) variant was significantly attenuated (18% mortality rate) and replicated to much lower titer in the brains of infected mice. A single amino acid substitution in the envelope (E) protein at E-240 (Ala-->Val) was identified as responsible for the restricted replication of the 17D(-wt) variant in vivo. The 17D(+wt) variant has an additional second-site mutation, believed to encode a reversion to the neurovirulence phenotype of the 17D-204 parent virus. The amino acid substitution in the E protein at E-173 (Thr-->Ile) of the 17D(+wt) variant which results in the appearance of the wild-type-specific epitope or nucleotide changes in the 5' and 3' noncoding regions of the virus are proposed as a candidates.

  4. Assessment of the genetic diversity of tomato yellow leaf curl virus.

    Science.gov (United States)

    Wan, H J; Yuan, W; Wang, R Q; Ye, Q J; Ruan, M Y; Li, Z M; Zhou, G Z; Yao, Z P; Yang, Y J

    2015-01-26

    The objective of the present study was to analyze the genetic diversity of tomato yellow leaf curl virus (TYLCV). Representative TYLCV sequences were searched in the National Center for Biotechnology Information database. Comprehensive analysis of TYLCV was performed using bioinformatics by examining gene structure, sequence alignments, phylogeny, GC content, and homology. Forty-eight representative TYLCV sequences were selected from 48 regions in 29 countries. The results showed that all TYLCV sequences were 2752-2794 nucleotides in length, which encoded 6 open reading frames (AV1, AV2, AC1, AC2, AC3, and AC4). GC content ranged from 0.41-0.42. Sequence alignment showed a number of insertions and deletions within these TYLCV sequences. Phylogenetic tree results revealed that the sequences were divided into 10 classes; homology of the sequences ranged from 72.8 to 98.6%. All 48 sequences contained the typical structure of TYLCV, including open reading frames and intergenic regions. These results provide a theoretical basis for the identification and evolution of the virus in the future.

  5. International travel between global urban centres vulnerable to yellow fever transmission.

    Science.gov (United States)

    Brent, Shannon E; Watts, Alexander; Cetron, Martin; German, Matthew; Kraemer, Moritz Ug; Bogoch, Isaac I; Brady, Oliver J; Hay, Simon I; Creatore, Maria I; Khan, Kamran

    2018-05-01

    To examine the potential for international travel to spread yellow fever virus to cities around the world. We obtained data on the international flight itineraries of travellers who departed yellow fever-endemic areas of the world in 2016 for cities either where yellow fever was endemic or which were suitable for viral transmission. Using a global ecological model of dengue virus transmission, we predicted the suitability of cities in non-endemic areas for yellow fever transmission. We obtained information on national entry requirements for yellow fever vaccination at travellers' destination cities. In 2016, 45.2 million international air travellers departed from yellow fever-endemic areas of the world. Of 11.7 million travellers with destinations in 472 cities where yellow fever was not endemic but which were suitable for virus transmission, 7.7 million (65.7%) were not required to provide proof of vaccination upon arrival. Brazil, China, India, Mexico, Peru and the United States of America had the highest volumes of travellers arriving from yellow fever-endemic areas and the largest populations living in cities suitable for yellow fever transmission. Each year millions of travellers depart from yellow fever-endemic areas of the world for cities in non-endemic areas that appear suitable for viral transmission without having to provide proof of vaccination. Rapid global changes in human mobility and urbanization make it vital for countries to re-examine their vaccination policies and practices to prevent urban yellow fever epidemics.

  6. Two Complete Genome Sequences of Phasey Bean Mild Yellows Virus, a Novel Member of the Luteoviridae from Australia

    OpenAIRE

    Sharman, Murray; Kehoe, Monica; Coutts, Brenda; van Leur, Joop; Filardo, Fiona; Thomas, John

    2016-01-01

    We present here the complete genome sequences of a novel polerovirus from Trifolium subterraneum (subterranean clover) and Cicer arietinum (chickpea) and compare these to a partial viral genome sequence obtained from Macroptilium lathyroides (phasey bean). We propose the name phasey bean mild yellows virus for this novel polerovirus.

  7. First report of Potato virus V and Peru tomato mosaic virus on tamarillo (Solanum betaceum) orchards of Ecuador

    Science.gov (United States)

    In Ecuador, tamarillo (Solanum betaceum) represents an important cash crop for hundreds of small farmers. In 2013, leaves from tamarillo plants showing severe virus-like symptoms (mosaic, mottling and leaf deformation) were collected from old orchards in Pichincha and Tungurahua. Double-stranded RN...

  8. A study of back-trap mottle in coated papers using electron probe microanalysis

    International Nuclear Information System (INIS)

    Eby, T.; Whalen-Shaw, M.

    1991-01-01

    In this paper methodology is been developed for analyzing both the surface and cross-sectional distributions for coating components using electron probe microanalysis and image analysis technology. Actual light and dark areas of print mottle are physically separated and analyzed to provide an unequivocal relationship between the distribution of coating components and the physical structure of the coating in areas of print mottle. Areas of low ink density were found to have higher surface latex concentration, greater mean coating thickness, and greater mean rawstock roughness. Furthermore, the difference in surface concentration of CaCO 3 within areas of, low and high ink density was established as a new and additional probable cause of back-trap mottle

  9. Oral infection of Aedes aegypti with yellow fever virus: geographic variation and genetic considerations.

    Science.gov (United States)

    Tabachnick, W J; Wallis, G P; Aitken, T H; Miller, B R; Amato, G D; Lorenz, L; Powell, J R; Beaty, B J

    1985-11-01

    Twenty-eight populations representing a worldwide distribution of Aedes aegypti were tested for their ability to become orally infected with yellow fever virus (YFV). Populations had been analyzed for genetic variations at 11 isozyme loci and assigned to one of 8 genetic geographic groups of Ae. aegypti. Infection rates suggest that populations showing isozyme genetic relatedness also demonstrate similarity to oral infection rates with YFV. The findings support the hypothesis that genetic variation exists for oral susceptibility to YFV in Ae. aegypti.

  10. A fatal yellow fever virus infection in China: description and lessons

    Science.gov (United States)

    Chen, Zhihai; Liu, Lin; Lv, Yanning; Zhang, Wei; Li, Jiandong; Zhang, Yi; Di, Tian; Zhang, Shuo; Liu, Jingyuan; Li, Jie; Qu, Jing; Hua, Wenhao; Li, Chuan; Wang, Peng; Zhang, Quanfu; Xu, Yanli; Jiang, Rongmeng; Wang, Qin; Chen, Lijuan; Wang, Shiwen; Pang, Xinghuo; Liang, Mifang; Ma, Xuejun; Li, Xingwang; Wang, Quanyi; Zhang, Fujie; Li, Dexin

    2016-01-01

    Yellow fever (YF) is a viral disease endemic to the tropical regions of Africa and South America. An outbreak of YF has been occurring in Angola, since the beginning of 2016. In March 2016, a 32-year-old Chinese man who returned from Angola was hospitalized and diagnosed with the first case of imported YF in China. Clinical observations, blood viral RNA detection, serological testing and treatments for the patient were performed daily. The virus was isolated in Vero cells, and the complete viral genome was sequenced and analyzed using the next-generation genomic sequencing platform. The patient presented with hemorrhagic fever, jaundice and oliguria at day 3 after onset, which rapidly progressed to multisystem organ failure with extremely elevated liver, pancreatic and myocardial enzymes. The patient died despite the intensive supportive treatments that were performed. A liver biopsy showed severe and multilobular necrosis. Viral RNA was detectable throughout the clinical course of the disease. Whole-genomic sequence analysis revealed that the virus belongs to the Angola71 genotype. Although the virus has been circulating in Angola for 45 years, only 14 amino-acid substitutions and no amino-acid changes were observed in the membrane and envelope proteins compared with the virus collected in 1971. The presence of this imported YF case in China indicated that with the increase in business travel among countries, YF outbreaks in Africa can lead to the international spread of the disease. The production and use of YF vaccines is, therefore, an urgent issue. PMID:27406389

  11. The nucleotide sequence of parsnip yellow fleck virus: a plant picorna-like virus.

    Science.gov (United States)

    Turnbull-Ross, A D; Reavy, B; Mayo, M A; Murant, A F

    1992-12-01

    The complete sequence of 9871 nucleotides (nts) of parsnip yellow fleck virus (PYFV; isolate P-121) was determined from cDNA clones and by direct sequencing of viral RNA. The RNA contains a large open reading frame between nts 279 and 9362 which encodes a polyprotein of 3027 amino acids with a calculated M(r) of 336212 (336K). A PYFV polyclonal antiserum reacted with the proteins expressed from phage carrying cDNA clones from the 5' half of the PYFV genome. Comparison of the polyprotein sequence of PYFV with other viral polyprotein sequences reveals similarities to the putative NTP-binding and RNA polymerase domains of cowpea mosaic comovirus, tomato black ring nepovirus and several animal picornaviruses. The 3' untranslated region of PYFV RNA is 509 nts long and does not have a poly(A) tail. The 3'-terminal 121 nts may form a stem-loop structure which resembles that formed in the genomic RNA of mosquito-borne flaviviruses.

  12. Complete Genome Sequence of Zucchini Yellow Mosaic Virus Strain Kurdistan, Iran.

    Science.gov (United States)

    Maghamnia, Hamid Reza; Hajizadeh, Mohammad; Azizi, Abdolbaset

    2018-03-01

    The complete genome sequence of Zucchini yellow mosaic virus strain Kurdistan (ZYMV-Kurdistan) infecting squash from Iran was determined from 13 overlapping fragments. Excluding the poly (A) tail, ZYMV-Kurdistan genome consisted of 9593 nucleotides (nt), with 138 and 211 nt at the 5' and 3' non-translated regions, respectively. It contained two open-reading frames (ORFs), the large ORF encoding a polyprotein of 3080 amino acids (aa) and the small overlapping ORF encoding a P3N-PIPO protein of 74 aa. This isolate had six unique aa differences compared to other ZYMV isolates and shared 79.6-98.8% identities with other ZYMV genome sequences at the nt level and 90.1-99% identities at the aa level. A phylogenetic tree of ZYMV complete genomic sequences showed that Iranian and Central European isolates are closely related and form a phylogenetically homogenous group. All values in the ratio of substitution rates at non-synonymous and synonymous sites ( d N / d S ) were below 1, suggestive of strong negative selection forces during ZYMV protein history. This is the first report of complete genome sequence information of the most prevalent virus in the west of Iran. This study helps our understanding of the genetic diversity of ZYMV isolates infecting cucurbit plants in Iran, virus evolution and epidemiology and can assist in designing better diagnostic tools.

  13. Atomic force microscopy investigation of Turnip Yellow Mosaic Virus capsid disruption and RNA extrusion

    International Nuclear Information System (INIS)

    Kuznetsov, Yu. G.; McPherson, Alexander

    2006-01-01

    Turnip Yellow Mosaic Virus (TYMV) was subjected to a variety of procedures which disrupted the protein capsids and produced exposure of the ssRNA genome. The results of the treatments were visualized by atomic force microscopy (AFM). Both in situ and ex situ freeze-thawing produced RNA emission, though at low efficiency. The RNA lost from such particles was evident, in some cases in the process of exiting the virions. More severe disruption of TYMV and extrusion of intact RNA onto the substrate were produced by drying the virus and rehydrating with neutral buffer. Similar products were also obtained by heating TYMV to 70-75 deg. C and by exposure to alkaline pH. Experiments showed the nucleic acid to have an elaborate secondary structure distributed linearly along its length

  14. The giant mottled eel, Anguilla marmorata, uses blue-shifted rod photoreceptors during upstream migration.

    Directory of Open Access Journals (Sweden)

    Feng-Yu Wang

    Full Text Available Catadromous fishes migrate between ocean and freshwater during particular phases of their life cycle. The dramatic environmental changes shape their physiological features, e.g. visual sensitivity, olfactory ability, and salinity tolerance. Anguilla marmorata, a catadromous eel, migrates upstream on dark nights, following the lunar cycle. Such behavior may be correlated with ontogenetic changes in sensory systems. Therefore, this study was designed to identify changes in spectral sensitivity and opsin gene expression of A. marmorata during upstream migration. Microspectrophotometry analysis revealed that the tropical eel possesses a duplex retina with rod and cone photoreceptors. The λmax of rod cells are 493, 489, and 489 nm in glass, yellow, and wild eels, while those of cone cells are 508, and 517 nm in yellow, and wild eels, respectively. Unlike European and American eels, Asian eels exhibited a blue-shifted pattern of rod photoreceptors during upstream migration. Quantitative gene expression analyses of four cloned opsin genes (Rh1f, Rh1d, Rh2, and SWS2 revealed that Rh1f expression is dominant at all three stages, while Rh1d is expressed only in older yellow eel. Furthermore, sequence comparison and protein modeling studies implied that a blue shift in Rh1d opsin may be induced by two known (N83, S292 and four putative (S124, V189, V286, I290 tuning sites adjacent to the retinal binding sites. Finally, expression of blue-shifted Rh1d opsin resulted in a spectral shift in rod photoreceptors. Our observations indicate that the giant mottled eel is color-blind, and its blue-shifted scotopic vision may influence its upstream migration behavior and habitat choice.

  15. Molecular Characterization of Tomato Yellow Leaf Curl Virus in Korea and the Construction of an Infectious Clone

    Directory of Open Access Journals (Sweden)

    Bong Choon Lee

    2015-06-01

    Full Text Available Several tomato production regions in Korea were surveyed for tomato yellow leaf curl disease (TYLCD. Tomato leaf samples showing TYLCD-like symptoms were collected from Tongyeong (To, Geoje (Gi, and Gimhae (Gh cities of the southern part of Korea. Tomato yellow leaf curl virus (TYLCV was detected and the full-length genomes of the isolates were sequenced. The TYLCV isolates found in Korea shared high sequence identity (> 99% with TYLCV-IL [JR:Omu:Ng] (AB110217. Phylogenetic relationship analysis revealed that they formed two groups (with little genetic variability, and the To, Gj, and Gh isolates belonged to the TYLCV-IL group. An infectious clone of TYLCV-To (JQ013089 was constructed and agroinoculated into Nicotiana benthamiana, Nicotiana tabacum var. Xanthi, Petunia hybrida, Capsicum annuum, and Lycopersicon esculentum cv. Hausumomotaro. Agroinfection with a dimeric infectious clone of TYLCV-To induced severe leaf curling and stunting symptoms in these plants, excluding C. annuum. Tomato plants then developed typical yellow leaf curl symptoms.

  16. The yellow fever 17D vaccine virus: molecular basis of viral attenuation and its use as an expression vector

    Directory of Open Access Journals (Sweden)

    Galler R.

    1997-01-01

    Full Text Available The yellow fever (YF virus is the prototype flavivirus. The use of molecular techniques has unraveled the basic mechanisms of viral genome structure and expression. Recent trends in flavivirus research include the use of infectious clone technology with which it is possible to recover virus from cloned cDNA. Using this technique, mutations can be introduced at any point of the viral genome and their resulting effect on virus phenotype can be assessed. This approach has opened new possibilities to study several biological viral features with special emphasis on the issue of virulence/attenuation of the YF virus. The feasibility of using YF virus 17D vaccine strain, for which infectious cDNA is available, as a vector for the expression of heterologous antigens is reviewed

  17. Neurovirulence of yellow fever 17DD vaccine virus to rhesus monkeys

    International Nuclear Information System (INIS)

    Marchevsky, Renato S.; Freire, Marcos S.; Coutinho, Evandro S.F.; Galler, Ricardo

    2003-01-01

    The yellow fever 17D virus is attenuated and used for human vaccination. Two of its substrains, 17D-204 and 17DD, are used for vaccine production. One of the remarkable properties of this vaccine is limited viral replication in the host but with significant dissemination of the viral mass, yielding a robust and long-lived neutralizing antibody response. The vaccine has excellent records of efficacy and safety and is cheap, used as a single dose, and there are well-established production methodology and quality control procedures which include the monkey neurovirulence test (MNTV). The present study aims at a better understanding of YF 17DD virus attenuation and immunogenicity in the MNVT with special emphasis on viremia, seroconversion, clinical and histological lesions scores, and their intrinsic variability across the tests. Several MNVTs were performed using the secondary seed lot virus 17DD 102/84 totaling 49 rhesus monkeys. Viremia was never higher than the accepted limits established in international requirements, and high levels of neutralizing antibodies were observed in all animals. None of the animals showed visceral lesions. We found that the clinical scores for the same virus varied widely across the tests. There was a direct correlation between the clinical scores in animals with clinical signs of encephalitis and a higher degree of central nervous system (CNS) histological lesions, with an increase of lesions in areas of the CNS such as the substantia nigra, nucleus caudatus, intumescentia cervicalis, and intumescentia ventralis. The histological scores were shown to be less prone to individual variations and had a more homogeneous value distribution among the tests. Since 17DD 102/84 seed virus has been used for human vaccine production and immunization for 16 years with the vaccine being safe and efficacious, it demonstrates that the observed variations across the MNVTs do not influence its effect on humans

  18. Serological and molecular studies of a novel virus isolate causing yellow mosaic of Patchouli [Pogostemon cablin (Blanco) Benth].

    Science.gov (United States)

    Zaim, Mohammad; Ali, Ashif; Joseph, Jomon; Khan, Feroz

    2013-01-01

    Here we have identified and characterized a devastating virus capable of inducing yellow mosaic on the leaves of Patchouli [Pogostemon cablin (Blanco) Benth]. The diagnostic tools used were host range, transmission studies, cytopathology, electron microscopy, serology and partial coat protein (CP) gene sequencing. Evidence from biological, serological and sequence data suggested that the causal virus belonged to genus Potyvirus, family Potyviridae. The isolate, designated as Patchouli Yellow Mosaic Virus (PaYMV), was transmitted through grafting, sap and the insect Myzus persicae (Sulz.). Flexuous rod shaped particles with a mean length of 800 nm were consistently observed in leaf-dip preparations from natural as well as alternate hosts, and in purified preparation. Cytoplasmic cylindrical inclusions, pinwheels and laminar aggregates were observed in ultra-thin sections of infected patchouli leaves. The purified capsid protein has a relative mass of 43 kDa. Polyclonal antibodies were raised in rabbits against the coat protein separated on SDS - PAGE; which were used in ELISA and western blotting. Using specific antibodies in ELISA, PaYMV was frequently detected at patchouli plantations at Lucknow and Bengaluru. Potyvirus-specific degenerate primer pair (U335 and D335) had consistently amplified partial CP gene from crude preparations of infected tissues by reverse transcription polymerase chain reaction (RT-PCR). Comparison of the PCR product sequence (290 bp) with the corresponding regions of established potyviruses showed 78-82% and 91-95% sequence similarity at the nucleotide and amino acid levels, respectively. The results clearly established that the virus under study has close homology with watermelon mosaic virus (WMV) in the coat protein region and therefore could share a common ancestor family. Further studies are required to authenticate the identity of PaYMV as a distinct virus or as an isolate of WMV.

  19. Spread of yellow fever virus outbreak in Angola and the Democratic Republic of the Congo 2015-16: a modelling study.

    Science.gov (United States)

    Kraemer, Moritz U G; Faria, Nuno R; Reiner, Robert C; Golding, Nick; Nikolay, Birgit; Stasse, Stephanie; Johansson, Michael A; Salje, Henrik; Faye, Ousmane; Wint, G R William; Niedrig, Matthias; Shearer, Freya M; Hill, Sarah C; Thompson, Robin N; Bisanzio, Donal; Taveira, Nuno; Nax, Heinrich H; Pradelski, Bary S R; Nsoesie, Elaine O; Murphy, Nicholas R; Bogoch, Isaac I; Khan, Kamran; Brownstein, John S; Tatem, Andrew J; de Oliveira, Tulio; Smith, David L; Sall, Amadou A; Pybus, Oliver G; Hay, Simon I; Cauchemez, Simon

    2017-03-01

    Since late 2015, an epidemic of yellow fever has caused more than 7334 suspected cases in Angola and the Democratic Republic of the Congo, including 393 deaths. We sought to understand the spatial spread of this outbreak to optimise the use of the limited available vaccine stock. We jointly analysed datasets describing the epidemic of yellow fever, vector suitability, human demography, and mobility in central Africa to understand and predict the spread of yellow fever virus. We used a standard logistic model to infer the district-specific yellow fever virus infection risk during the course of the epidemic in the region. The early spread of yellow fever virus was characterised by fast exponential growth (doubling time of 5-7 days) and fast spatial expansion (49 districts reported cases after only 3 months) from Luanda, the capital of Angola. Early invasion was positively correlated with high population density (Pearson's r 0·52, 95% CI 0·34-0·66). The further away locations were from Luanda, the later the date of invasion (Pearson's r 0·60, 95% CI 0·52-0·66). In a Cox model, we noted that districts with higher population densities also had higher risks of sustained transmission (the hazard ratio for cases ceasing was 0·74, 95% CI 0·13-0·92 per log-unit increase in the population size of a district). A model that captured human mobility and vector suitability successfully discriminated districts with high risk of invasion from others with a lower risk (area under the curve 0·94, 95% CI 0·92-0·97). If at the start of the epidemic, sufficient vaccines had been available to target 50 out of 313 districts in the area, our model would have correctly identified 27 (84%) of the 32 districts that were eventually affected. Our findings show the contributions of ecological and demographic factors to the ongoing spread of the yellow fever outbreak and provide estimates of the areas that could be prioritised for vaccination, although other constraints such as vaccine

  20. Structure of the C-terminal domain of lettuce necrotic yellows virus phosphoprotein.

    Science.gov (United States)

    Martinez, Nicolas; Ribeiro, Euripedes A; Leyrat, Cédric; Tarbouriech, Nicolas; Ruigrok, Rob W H; Jamin, Marc

    2013-09-01

    Lettuce necrotic yellows virus (LNYV) is a prototype of the plant-adapted cytorhabdoviruses. Through a meta-prediction of disorder, we localized a folded C-terminal domain in the amino acid sequence of its phosphoprotein. This domain consists of an autonomous folding unit that is monomeric in solution. Its structure, solved by X-ray crystallography, reveals a lollipop-shaped structure comprising five helices. The structure is different from that of the corresponding domains of other Rhabdoviridae, Filoviridae, and Paramyxovirinae; only the overall topology of the polypeptide chain seems to be conserved, suggesting that this domain evolved under weak selective pressure and varied in size by the acquisition or loss of functional modules.

  1. Influence of microscopic mottle on the definition of small image details

    Energy Technology Data Exchange (ETDEWEB)

    Selin, K; Reichmann, S [Sahlgrenska Sjukhuset, Goeteborg (Sweden)

    1979-01-01

    By a special technique of enlarging films a microscopic mottle caused by quantum fluctuations was demonstrated. It was found to affect depiction of small details in such a way as to suggest that it would be of importance for determining resolution capacity, especially in high-speed radiography. Thus, the modulation transfer function appears not to be the only factor determining radiographic resolution. The resolution of high-speed screens may be improved if the film speed is reduced, which leads to a diminished microscopic mottle.

  2. Further molecular characterization of weed-associated begomoviruses in Brazil with an emphasis on Sida spp Caracterização molecular adicional de begomovírus associados a plantas daninhas no Brasil, com ênfase em Sida spp

    Directory of Open Access Journals (Sweden)

    S.S. Tavares

    2012-06-01

    Full Text Available Begomoviruses are whitefly-transmitted, single-stranded DNA viruses that are often associated with weed plants. The aim of this study was to further characterize the diversity of begomoviruses infecting weeds (mostly Sida spp. in Brazil. Total DNA was extracted from weed samples collected in Viçosa (Minas Gerais state and in some municipalities of Alagoas state in 2009 and 2010. Viral genomes were amplified by RCA, cloned and sequenced. A total of 26 DNA-A clones were obtained. Sequence analysis indicated the presence of 10 begomoviruses. All viral isolates from Blainvillea rhomboidea belonged to the same species, Blainvillea yellow spot virus (BlYSV , thereby suggesting that BlYSV may be the only begomovirus present in this weed species. Four isolates represent new species, for which the following names are proposed: Sida yellow blotch virus (SiYBV, Sida yellow net virus (SiYNV, Sida mottle Alagoas virus (SiMoAV and Sida yellow mosaic Alagoas virus (SiYMAV. Recombination events were detected among the SiYBV isolates and in the SiYNV isolate. These results constitute further evidence of the high species diversity of begomoviruses in Sida spp. However, the role of this weed species as a source of begomoviruses infecting crop plants remains to be determined.Begomovírus são vírus de DNA circular fita simples transmitidos por mosca branca, os quais são frequentemente associados com plantas daninhas. O objetivo deste trabalho foi caracterizar a diversidade de begomovírus infectando plantas daninhas (principalmente Sida spp. no Brasil. DNA total foi extraído a partir de plantas daninhas coletadas em Viçosa (Minas Gerais e em alguns municípios do estado de Alagoas em 2009 e 2010. Os genomas virais foram amplificados por RCA, clonados e sequenciados. Um total de 26 clones de DNA-A foram obtidos. A análise das sequências indicou a presença de dez diferentes begomovírus. Todos os isolados originários de Blainvillea rhomboidea pertencem a uma

  3. Rapid molecular assays for the detection of yellow fever virus in low-resource settings.

    Science.gov (United States)

    Escadafal, Camille; Faye, Oumar; Sall, Amadou Alpha; Faye, Ousmane; Weidmann, Manfred; Strohmeier, Oliver; von Stetten, Felix; Drexler, Josef; Eberhard, Michael; Niedrig, Matthias; Patel, Pranav

    2014-03-01

    Yellow fever (YF) is an acute viral hemorrhagic disease transmitted by Aedes mosquitoes. The causative agent, the yellow fever virus (YFV), is found in tropical and subtropical areas of South America and Africa. Although a vaccine is available since the 1930s, YF still causes thousands of deaths and several outbreaks have recently occurred in Africa. Therefore, rapid and reliable diagnostic methods easy to perform in low-resources settings could have a major impact on early detection of outbreaks and implementation of appropriate response strategies such as vaccination and/or vector control. The aim of this study was to develop a YFV nucleic acid detection method applicable in outbreak investigations and surveillance studies in low-resource and field settings. The method should be simple, robust, rapid and reliable. Therefore, we adopted an isothermal approach and developed a recombinase polymerase amplification (RPA) assay which can be performed with a small portable instrument and easy-to-use lyophilized reagents. The assay was developed in three different formats (real-time with or without microfluidic semi-automated system and lateral-flow assay) to evaluate their application for different purposes. Analytical specificity and sensitivity were evaluated with a wide panel of viruses and serial dilutions of YFV RNA. Mosquito pools and spiked human plasma samples were also tested for assay validation. Finally, real-time RPA in portable format was tested under field conditions in Senegal. The assay was able to detect 20 different YFV strains and demonstrated no cross-reactions with closely related viruses. The RPA assay proved to be a robust, portable method with a low detection limit (<21 genome equivalent copies per reaction) and rapid processing time (<20 min). Results from real-time RPA field testing were comparable to results obtained in the laboratory, thus confirming our method is suitable for YFV detection in low-resource settings.

  4. Rapid molecular assays for the detection of yellow fever virus in low-resource settings.

    Directory of Open Access Journals (Sweden)

    Camille Escadafal

    2014-03-01

    Full Text Available BACKGROUND: Yellow fever (YF is an acute viral hemorrhagic disease transmitted by Aedes mosquitoes. The causative agent, the yellow fever virus (YFV, is found in tropical and subtropical areas of South America and Africa. Although a vaccine is available since the 1930s, YF still causes thousands of deaths and several outbreaks have recently occurred in Africa. Therefore, rapid and reliable diagnostic methods easy to perform in low-resources settings could have a major impact on early detection of outbreaks and implementation of appropriate response strategies such as vaccination and/or vector control. METHODOLOGY: The aim of this study was to develop a YFV nucleic acid detection method applicable in outbreak investigations and surveillance studies in low-resource and field settings. The method should be simple, robust, rapid and reliable. Therefore, we adopted an isothermal approach and developed a recombinase polymerase amplification (RPA assay which can be performed with a small portable instrument and easy-to-use lyophilized reagents. The assay was developed in three different formats (real-time with or without microfluidic semi-automated system and lateral-flow assay to evaluate their application for different purposes. Analytical specificity and sensitivity were evaluated with a wide panel of viruses and serial dilutions of YFV RNA. Mosquito pools and spiked human plasma samples were also tested for assay validation. Finally, real-time RPA in portable format was tested under field conditions in Senegal. CONCLUSION/SIGNIFICANCE: The assay was able to detect 20 different YFV strains and demonstrated no cross-reactions with closely related viruses. The RPA assay proved to be a robust, portable method with a low detection limit (<21 genome equivalent copies per reaction and rapid processing time (<20 min. Results from real-time RPA field testing were comparable to results obtained in the laboratory, thus confirming our method is suitable for

  5. Transfusion-related transmission of yellow fever vaccine virus--California, 2009.

    Science.gov (United States)

    2010-01-22

    In the United States, yellow fever (YF) vaccination is recommended for travelers and active duty military members visiting endemic areas of sub-Saharan Africa and Central/South America. The American Red Cross recommends that recipients of YF vaccine defer blood product donation for 2 weeks because of the theoretical risk for transmission from a viremic donor. On April 10, 2009, a hospital blood bank supervisor learned that, on March 27, blood products had been collected from 89 U.S. active duty trainees who had received YF vaccine 4 days before donation. This report summarizes the subsequent investigation by the hospital and CDC to identify lapses in donor deferral and to determine whether transfusion-related transmission of YF vaccine virus occurred. The investigation found that a recent change in the timing of trainee vaccination had occurred and that vaccinees had not reported recent YF vaccination status at time of donation. Despite a prompt recall, six units of blood products were transfused into five patients. No clinical evidence or laboratory abnormalities consistent with a serious adverse reaction were identified in four recipients within the first month after transfusion; the fifth patient, who had prostate cancer and end-stage, transfusion-dependent, B-cell lymphoma, died while in hospice care. Three of the four surviving patients had evidence of serologic response to YF vaccine virus. This report provides evidence that transfusion-related transmission of YF vaccine virus can occur and underscores the need for careful screening and deferral of recently vaccinated blood donors.

  6. Attenuation and immunogenicity of recombinant yellow fever 17D-dengue type 2 virus for rhesus monkeys

    Directory of Open Access Journals (Sweden)

    Galler R.

    2005-01-01

    Full Text Available A chimeric yellow fever (YF-dengue serotype 2 (dengue 2 virus was constructed by replacing the premembrane and envelope genes of the YF 17D virus with those from dengue 2 virus strains of Southeast Asian genotype. The virus grew to high titers in Vero cells and, after passage 2, was used for immunogenicity and attenuation studies in rhesus monkeys. Subcutaneous immunization of naive rhesus monkeys with the 17D-D2 chimeric virus induced a neutralizing antibody response associated with the protection of 6 of 7 monkeys against viremia by wild-type dengue 2 virus. Neutralizing antibody titers to dengue 2 were significantly lower in YF-immune animals than in YF-naive monkeys and protection against challenge with wild-type dengue 2 virus was observed in only 2 of 11 YF-immune monkeys. An anamnestic response to dengue 2, indicated by a sharp increase of neutralizing antibody titers, was observed in the majority of the monkeys after challenge with wild-type virus. Virus attenuation was demonstrated using the standard monkey neurovirulence test. The 17D-D2 chimera caused significantly fewer histological lesions than the YF 17DD virus. The attenuated phenotype could also be inferred from the limited viremias compared to the YF 17DD vaccine. Overall, these results provide further support for the use of chimeric viruses for the development of a new live tetravalent dengue vaccine.

  7. New research on the origin of mottled clay in Quaternary basins in the coastal area of south China

    Science.gov (United States)

    Wang, Jing; Chen, Zhen; Gao, Quanzhou; Chen, Guoneng

    2018-06-01

    Last Glacial Maximum (LGM) mottled clay occurs widely in Late Quaternary basins in south China coastal areas. Current research attributes its origin to exposure weathering of Late Pleistocene marine/fluvial deposits during the LGM. However, field data suggest that this is not the case as there is no gradual transition in lithology, grain size, structure and material composition among these layers. Instead, the mottled clay possesses sedimentary characteristics of exotic dust. In this study, three typical drill cores in the Pearl River Delta were studied using grain size analysis, diffuse reflection spectroscopy (DRS) and geochemical analysis to ascertain the clay's sedimentary characteristics and origin. Grain size distribution patterns and parameters of the mottled clay were similar to those of a typical loess, indicating aeolian origin. In DRS curves, the peak height of hematite > goethite, indicating that the mottled clay had not experienced strong hydration and constitutes a continental product. This conforms to a typical loess but differs from the underlying marine/fluvial deposits. The chemical composition of the mottled clay was homogeneous in the vertical and planar directions. Upper continental crust (UCC) normalized curves of major and trace elements of the mottled clay were close to the average UCC and were consistent with typical aeolian deposits. The spatial and temporal distribution characteristics and relationship with the underlying layer suggest that the mottled clay was a loess-like deposit during the LGM and its mottled structure originated from strong modification of oxidation during the postglacial period after homogeneous dust had accumulated.

  8. Genomic and proteomic analysis of Schizaphis graminum reveals cyclophilin proteins are involved in the transmission of cereal yellow dwarf virus.

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    Cecilia Tamborindeguy

    Full Text Available Yellow dwarf viruses cause the most economically important virus diseases of cereal crops worldwide and are transmitted by aphid vectors. The identification of aphid genes and proteins mediating virus transmission is critical to develop agriculturally sustainable virus management practices and to understand viral strategies for circulative movement in all insect vectors. Two cyclophilin B proteins, S28 and S29, were identified previously in populations of Schizaphisgraminum that differed in their ability to transmit the RPV strain of Cereal yellow dwarf virus (CYDV-RPV. The presence of S29 was correlated with F2 genotypes that were efficient virus transmitters. The present study revealed the two proteins were isoforms, and a single amino acid change distinguished S28 and S29. The distribution of the two alleles was determined in 12 F2 genotypes segregating for CYDV-RPV transmission capacity and in 11 genetically independent, field-collected S. graminum biotypes. Transmission efficiency for CYDV-RPV was determined in all genotypes and biotypes. The S29 isoform was present in all genotypes or biotypes that efficiently transmit CYDV-RPV and more specifically in genotypes that efficiently transport virus across the hindgut. We confirmed a direct interaction between CYDV-RPV and both S28 and S29 using purified virus and bacterially expressed, his-tagged S28 and S29 proteins. Importantly, S29 failed to interact with a closely related virus that is transported across the aphid midgut. We tested for in vivo interactions using an aphid-virus co-immunoprecipitation strategy coupled with a bottom-up LC-MS/MS analysis using a Q Exactive mass spectrometer. This analysis enabled us to identify a third cyclophilin protein, cyclophilin A, interacting directly or in complex with purified CYDV-RPV. Taken together, these data provide evidence that both cyclophilin A and B interact with CYDV-RPV, and these interactions may be important but not sufficient to mediate

  9. Exploiting Fluorescent Polymers To Probe the Self-Assembly of Virus-like Particles

    DEFF Research Database (Denmark)

    Caden-Nava, Ruben D.; Hu, Yufang; Garmann, Rees F.

    2011-01-01

    , for example, poly(styrene sulfonate) (PSS), forming virus-like particles (VLPs). We have demonstrated recently that the VLPs formed from cowpea chlorotic mottle virus (CCMV) capsid protein increase in size (from T = 2 to T = 3 structures) upon increase in PSS molecular weight (from 400 kDa to 3.4MDa...

  10. Two Complete Genome Sequences of Phasey Bean Mild Yellows Virus, a Novel Member of the Luteoviridae from Australia.

    Science.gov (United States)

    Sharman, Murray; Kehoe, Monica; Coutts, Brenda; van Leur, Joop; Filardo, Fiona; Thomas, John

    2016-02-04

    We present here the complete genome sequences of a novel polerovirus from Trifolium subterraneum (subterranean clover) and Cicer arietinum (chickpea) and compare these to a partial viral genome sequence obtained from Macroptilium lathyroides (phasey bean). We propose the name phasey bean mild yellows virus for this novel polerovirus. Copyright © 2016 Sharman et al.

  11. Yellow Fever 17DD Vaccine Virus Infection Causes Detectable Changes in Chicken Embryos.

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    Pedro Paulo de Abreu Manso

    Full Text Available The yellow fever (YF 17D vaccine is one of the most effective human vaccines ever created. The YF vaccine has been produced since 1937 in embryonated chicken eggs inoculated with the YF 17D virus. Yet, little information is available about the infection mechanism of YF 17DD virus in this biological model. To better understand this mechanism, we infected embryos of Gallus gallus domesticus and analyzed their histopathology after 72 hours of YF infection. Some embryos showed few apoptotic bodies in infected tissues, suggesting mild focal infection processes. Confocal and super-resolution microscopic analysis allowed us to identify as targets of viral infection: skeletal muscle cells, cardiomyocytes, nervous system cells, renal tubular epithelium, lung parenchyma, and fibroblasts associated with connective tissue in the perichondrium and dermis. The virus replication was heaviest in muscle tissues. In all of these specimens, RT-PCR methods confirmed the presence of replicative intermediate and genomic YF RNA. This clearer characterization of cell targets in chicken embryos paves the way for future development of a new YF vaccine based on a new cell culture system.

  12. The RNA of turnip yellow mosaic virus exhibits icosahedral order

    International Nuclear Information System (INIS)

    Larson, Steven B.; Lucas, Robert W.; Greenwood, Aaron; McPherson, Alexander

    2005-01-01

    Difference electron density maps, based on structure factor amplitudes and experimental phases from crystals of wild-type turnip yellow mosaic virus and those of empty capsids prepared by freeze-thawing, show a large portion of the encapsidated RNA to have an icosahedral distribution. Four unique segments of base-paired, double-helical RNA, one to two turns in length, lie between 33-A and 101-A radius and are organized about either 2-fold or 5-fold icosahedral axes. In addition, single-stranded loops of RNA invade the pentameric and hexameric capsomeres where they contact the interior capsid surface. The remaining RNA, not seen in electron density maps, must serve as connecting links between these secondary structural elements and is likely icosahedrally disordered. The distribution of RNA observed crystallographically appears to be in agreement with models based on biochemical data and secondary structural analyses

  13. Attenuation of Recombinant Yellow Fever 17D Viruses Expressing Foreign Protein Epitopes at the Surface

    Science.gov (United States)

    Bonaldo, Myrna C.; Garratt, Richard C.; Marchevsky, Renato S.; Coutinho, Evandro S. F.; Jabor, Alfredo V.; Almeida, Luís F. C.; Yamamura, Anna M. Y.; Duarte, Adriana S.; Oliveira, Prisciliana J.; Lizeu, Jackeline O. P.; Camacho, Luiz A. B.; Freire, Marcos S.; Galler, Ricardo

    2005-01-01

    The yellow fever (YF) 17D vaccine is a live attenuated virus. Three-dimensional (3D) homology modeling of the E protein structure from YF 17D virus and its comparison with that from tick-borne encephalitis virus revealed that it is possible to accommodate inserts of different sizes and amino acid compositions in the flavivirus E protein fg loop. This is consistent with the 3D structures of both the dimeric and trimeric forms in which the fg loop lies exposed to solvents. We demonstrate here that YF 17D viruses bearing foreign humoral (17D/8) and T-cell (17D/13) epitopes, which vary in sequence and length, displayed growth restriction. It is hypothesized that interference with the dimer-trimer transition and with the formation of a ring of such trimers in order to allow fusion compromises the capability of the E protein to induce fusion of viral and endosomal membranes, and a slower rate of fusion may delay the extent of virus production. This would account for the lower levels of replication in cultured cells and of viremia in monkeys, as well as for the more attenuated phenotype of the recombinant viruses in monkeys. Testing of both recombinant viruses (17D/8 and 17D/13) for monkey neurovirulence also suggests that insertion at the 17D E protein fg loop does not compromise the attenuated phenotype of YF 17D virus, further confirming the potential use of this site for the development of new live attenuated 17D virus-based vaccines. PMID:15956601

  14. Identification of three genotypes of sugarcane yellow leaf virus causing yellow leaf disease from India and their molecular characterization.

    Science.gov (United States)

    Viswanathan, R; Balamuralikrishnan, M; Karuppaiah, R

    2008-12-01

    Sugarcane yellow leaf virus (SCYLV) that causes yellow leaf disease (YLD) in sugarcane (recently reported in India) belongs to Polerovirus. Detailed studies were conducted to characterize the virus based on partial open reading frames (ORFs) 1 and 2 and complete ORFs 3 and 4 sequences in their genome. Reverse-transcriptase polymerase chain reaction (RT-PCR) was performed on 48 sugarcane leaf samples to detect the virus using a specific set of primers. Of the 48 samples, 36 samples (field samples with and without foliar symptoms) including 10 meristem culture derived plants were found to be positive to SCYLV infection. Additionally, an aphid colony collected from symptomatic sugarcane in the field was also found to be SCYLV positive. The amplicons from 22 samples were cloned, sequenced and acronymed as SCYLV-CB isolates. The nucleotide (nt) and amino acid (aa) sequence comparison showed a significant variation between SCYLV-CB and the database sequences at nt (3.7-5.1%) and aa (3.2-5.3%) sequence level in the CP coding region. However, the database sequences comprising isolates of three reported genotypes, viz., BRA, PER and REU, were observed with least nt and aa sequence dissimilarities (0.0-1.6%). The phylogenetic analyses of the overlapping ORFs (ORF 3 and ORF 4) of SCYLV encoding CP and MP determined in this study and additional sequences of 26 other isolates including an Indian isolate (SCYLV-IND) available from GenBank were distributed in four phylogenetic clusters. The SCYLV-CB isolates from this study lineated in two clusters (C1 and C2) and all the other isolates from the worldwide locations into another two clusters (C3 and C4). The sequence variation of the isolates in this study with the database isolates, even in the least variable region of the SCYLV genome, showed that the population existing in India is significantly different from rest of the world. Further, comparison of partial sequences encoding for ORFs 1 and 2 revealed that YLD in sugarcane in

  15. The complete genomic sequence of pepper yellow leaf curl virus (PYLCV and its implications for our understanding of evolution dynamics in the genus polerovirus.

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    Aviv Dombrovsky

    Full Text Available We determined the complete sequence and organization of the genome of a putative member of the genus Polerovirus tentatively named Pepper yellow leaf curl virus (PYLCV. PYLCV has a wider host range than Tobacco vein-distorting virus (TVDV and has a close serological relationship with Cucurbit aphid-borne yellows virus (CABYV (both poleroviruses. The extracted viral RNA was subjected to SOLiD next-generation sequence analysis and used as a template for reverse transcription synthesis, which was followed by PCR amplification. The ssRNA genome of PYLCV includes 6,028 nucleotides encoding six open reading frames (ORFs, which is typical of the genus Polerovirus. Comparisons of the deduced amino acid sequences of the PYLCV ORFs 2-4 and ORF5, indicate that there are high levels of similarity between these sequences to ORFs 2-4 of TVDV (84-93% and to ORF5 of CABYV (87%. Both PYLCV and Pepper vein yellowing virus (PeVYV contain sequences that point to a common ancestral polerovirus. The recombination breakpoint which is located at CABYV ORF3, which encodes the viral coat protein (CP, may explain the CABYV-like sequences found in the genomes of the pepper infecting viruses PYLCV and PeVYV. Two additional regions unique to PYLCV (PY1 and PY2 were identified between nucleotides 4,962 and 5,061 (ORF 5 and between positions 5,866 and 6,028 in the 3' NCR. Sequence analysis of the pepper-infecting PeVYV revealed three unique regions (Pe1-Pe3 with no similarity to other members of the genus Polerovirus. Genomic analyses of PYLCV and PeVYV suggest that the speciation of these viruses occurred through putative recombination event(s between poleroviruses co-infecting a common host(s, resulting in the emergence of PYLCV, a novel pathogen with a wider host range.

  16. The complete genomic sequence of pepper yellow leaf curl virus (PYLCV) and its implications for our understanding of evolution dynamics in the genus polerovirus.

    Science.gov (United States)

    Dombrovsky, Aviv; Glanz, Eyal; Lachman, Oded; Sela, Noa; Doron-Faigenboim, Adi; Antignus, Yehezkel

    2013-01-01

    We determined the complete sequence and organization of the genome of a putative member of the genus Polerovirus tentatively named Pepper yellow leaf curl virus (PYLCV). PYLCV has a wider host range than Tobacco vein-distorting virus (TVDV) and has a close serological relationship with Cucurbit aphid-borne yellows virus (CABYV) (both poleroviruses). The extracted viral RNA was subjected to SOLiD next-generation sequence analysis and used as a template for reverse transcription synthesis, which was followed by PCR amplification. The ssRNA genome of PYLCV includes 6,028 nucleotides encoding six open reading frames (ORFs), which is typical of the genus Polerovirus. Comparisons of the deduced amino acid sequences of the PYLCV ORFs 2-4 and ORF5, indicate that there are high levels of similarity between these sequences to ORFs 2-4 of TVDV (84-93%) and to ORF5 of CABYV (87%). Both PYLCV and Pepper vein yellowing virus (PeVYV) contain sequences that point to a common ancestral polerovirus. The recombination breakpoint which is located at CABYV ORF3, which encodes the viral coat protein (CP), may explain the CABYV-like sequences found in the genomes of the pepper infecting viruses PYLCV and PeVYV. Two additional regions unique to PYLCV (PY1 and PY2) were identified between nucleotides 4,962 and 5,061 (ORF 5) and between positions 5,866 and 6,028 in the 3' NCR. Sequence analysis of the pepper-infecting PeVYV revealed three unique regions (Pe1-Pe3) with no similarity to other members of the genus Polerovirus. Genomic analyses of PYLCV and PeVYV suggest that the speciation of these viruses occurred through putative recombination event(s) between poleroviruses co-infecting a common host(s), resulting in the emergence of PYLCV, a novel pathogen with a wider host range.

  17. Structure of the C-Terminal Domain of Lettuce Necrotic Yellows Virus Phosphoprotein

    Science.gov (United States)

    Martinez, Nicolas; Ribeiro, Euripedes A.; Leyrat, Cédric; Tarbouriech, Nicolas; Ruigrok, Rob W. H.

    2013-01-01

    Lettuce necrotic yellows virus (LNYV) is a prototype of the plant-adapted cytorhabdoviruses. Through a meta-prediction of disorder, we localized a folded C-terminal domain in the amino acid sequence of its phosphoprotein. This domain consists of an autonomous folding unit that is monomeric in solution. Its structure, solved by X-ray crystallography, reveals a lollipop-shaped structure comprising five helices. The structure is different from that of the corresponding domains of other Rhabdoviridae, Filoviridae, and Paramyxovirinae; only the overall topology of the polypeptide chain seems to be conserved, suggesting that this domain evolved under weak selective pressure and varied in size by the acquisition or loss of functional modules. PMID:23785215

  18. Development of three full-length infectious cDNA clones of distinct brassica yellows virus genotypes for agrobacterium-mediated inoculation.

    Science.gov (United States)

    Zhang, Xiao-Yan; Dong, Shu-Wei; Xiang, Hai-Ying; Chen, Xiang-Ru; Li, Da-Wei; Yu, Jia-Lin; Han, Cheng-Gui

    2015-02-02

    Brassica yellows virus is a newly identified species in the genus of Polerovirus within the family Luteoviridae. Brassica yellows virus (BrYV) is prevalently distributed throughout Mainland China and South Korea, is an important virus infecting cruciferous crops. Based on six BrYV genomic sequences of isolates from oilseed rape, rutabaga, radish, and cabbage, three genotypes, BrYV-A, BrYV-B, and BrYV-C, exist, which mainly differ in the 5' terminal half of the genome. BrYV is an aphid-transmitted and phloem-limited virus. The use of infectious cDNA clones is an alternative means of infecting plants that allows reverse genetic studies to be performed. In this study, full-length cDNA clones of BrYV-A, recombinant BrYV5B3A, and BrYV-C were constructed under control of the cauliflower mosaic virus 35S promoter. An agrobacterium-mediated inoculation system of Nicotiana benthamiana was developed using these cDNA clones. Three days after infiltration with full-length BrYV cDNA clones, necrotic symptoms were observed in the inoculated leaves of N. benthamiana; however, no obvious symptoms appeared in the upper leaves. Reverse transcription-PCR (RT-PCR) and western blot detection of samples from the upper leaves showed that the maximum infection efficiency of BrYVs could reach 100%. The infectivity of the BrYV-A, BrYV-5B3A, and BrYV-C cDNA clones was further confirmed by northern hybridization. The system developed here will be useful for further studies of BrYV, such as host range, pathogenicity, viral gene functions, and plant-virus-vector interactions, and especially for discerning the differences among the three genotypes. Copyright © 2014 Elsevier B.V. All rights reserved.

  19. Yellow fever virus capsid protein is a potent suppressor of RNA silencing that binds double-stranded RNA.

    Science.gov (United States)

    Samuel, Glady Hazitha; Wiley, Michael R; Badawi, Atif; Adelman, Zach N; Myles, Kevin M

    2016-11-29

    Mosquito-borne flaviviruses, including yellow fever virus (YFV), Zika virus (ZIKV), and West Nile virus (WNV), profoundly affect human health. The successful transmission of these viruses to a human host depends on the pathogen's ability to overcome a potentially sterilizing immune response in the vector mosquito. Similar to other invertebrate animals and plants, the mosquito's RNA silencing pathway comprises its primary antiviral defense. Although a diverse range of plant and insect viruses has been found to encode suppressors of RNA silencing, the mechanisms by which flaviviruses antagonize antiviral small RNA pathways in disease vectors are unknown. Here we describe a viral suppressor of RNA silencing (VSR) encoded by the prototype flavivirus, YFV. We show that the YFV capsid (YFC) protein inhibits RNA silencing in the mosquito Aedes aegypti by interfering with Dicer. This VSR activity appears to be broadly conserved in the C proteins of other medically important flaviviruses, including that of ZIKV. These results suggest that a molecular "arms race" between vector and pathogen underlies the continued existence of flaviviruses in nature.

  20. Yellow fever virus envelope protein expressed in insect cells is capable of syncytium formation in lepidopteran cells and could be used for immunodetection of YFV in human sera

    Directory of Open Access Journals (Sweden)

    Nagata Tatsuya

    2011-05-01

    Full Text Available Abstract Background Yellow fever is an haemorrhagic disease caused by a virus that belongs to the genus Flavivirus (Flaviviridae family and is transmitted by mosquitoes. Among the viral proteins, the envelope protein (E is the most studied one, due to its high antigenic potencial. Baculovirus are one of the most popular and efficient eukaryotic expression system. In this study a recombinant baculovirus (vSynYFE containing the envelope gene (env of the 17D vaccine strain of yellow fever virus was constructed and the recombinant protein antigenicity was tested. Results Insect cells infected with vSynYFE showed syncytium formation, which is a cytopathic effect characteristic of flavivirus infection and expressed a polypeptide of around 54 kDa, which corresponds to the expected size of the recombinant E protein. Furthermore, the recombinant E protein expression was also confirmed by fluorescence microscopy of vSynYFE-infected insect cells. Total vSynYFE-infected insect extracts used as antigens detected the presence of antibodies for yellow fever virus in human sera derived from yellow fever-infected patients in an immunoassay and did not cross react with sera from dengue virus-infected patients. Conclusions The E protein expressed by the recombinant baculovirus in insect cells is antigenically similar to the wild protein and it may be useful for different medical applications, from improved diagnosis of the disease to source of antigens for the development of a subunit vaccine.

  1. Surveillance for yellow Fever virus in non-human primates in southern Brazil, 2001-2011: a tool for prioritizing human populations for vaccination.

    OpenAIRE

    Marco A B Almeida; Jader da C Cardoso; Edmilson Dos Santos; Daltro F da Fonseca; Laura L Cruz; Fernando J C Faraco; Marilina A Bercini; Kátia C Vettorello; Mariana A Porto; Renate Mohrdieck; Tani M S Ranieri; Maria T Schermann; Alethéa F Sperb; Francisco Z Paz; Zenaida M A Nunes

    2014-01-01

    Author Summary Yellow fever (YF) is a viral hemorrhagic disease that affects humans as well as several species of non-human primates, especially New World monkeys found in South America. Yellow fever virus (YFV) is maintained in a natural cycle involving tree-hole breeding mosquitoes and non-human primates hosts. Because YF is often fatal in susceptible New World monkey populations, sudden die-offs of New World monkeys or epizootics can signal YFV circulation in an environment where humans ma...

  2. A DNA vaccine against yellow fever virus: development and evaluation.

    Directory of Open Access Journals (Sweden)

    Milton Maciel

    2015-04-01

    Full Text Available Attenuated yellow fever (YF virus 17D/17DD vaccines are the only available protection from YF infection, which remains a significant source of morbidity and mortality in the tropical areas of the world. The attenuated YF virus vaccine, which is used worldwide, generates both long-lasting neutralizing antibodies and strong T-cell responses. However, on rare occasions, this vaccine has toxic side effects that can be fatal. This study presents the design of two non-viral DNA-based antigen formulations and the characterization of their expression and immunological properties. The two antigen formulations consist of DNA encoding the full-length envelope protein (p/YFE or the full-length envelope protein fused to the lysosomal-associated membrane protein signal, LAMP-1 (pL/YFE, aimed at diverting antigen processing/presentation through the major histocompatibility complex II precursor compartments. The immune responses triggered by these formulations were evaluated in H2b and H2d backgrounds, corresponding to the C57Bl/6 and BALB/c mice strains, respectively. Both DNA constructs were able to induce very strong T-cell responses of similar magnitude against almost all epitopes that are also generated by the YF 17DD vaccine. The pL/YFE formulation performed best overall. In addition to the T-cell response, it was also able to stimulate high titers of anti-YF neutralizing antibodies comparable to the levels elicited by the 17DD vaccine. More importantly, the pL/YFE vaccine conferred 100% protection against the YF virus in intracerebrally challenged mice. These results indicate that pL/YFE DNA is an excellent vaccine candidate and should be considered for further developmental studies.

  3. A DNA vaccine against yellow fever virus: development and evaluation.

    Science.gov (United States)

    Maciel, Milton; Cruz, Fábia da Silva Pereira; Cordeiro, Marli Tenório; da Motta, Márcia Archer; Cassemiro, Klécia Marília Soares de Melo; Maia, Rita de Cássia Carvalho; de Figueiredo, Regina Célia Bressan Queiroz; Galler, Ricardo; Freire, Marcos da Silva; August, Joseph Thomas; Marques, Ernesto T A; Dhalia, Rafael

    2015-04-01

    Attenuated yellow fever (YF) virus 17D/17DD vaccines are the only available protection from YF infection, which remains a significant source of morbidity and mortality in the tropical areas of the world. The attenuated YF virus vaccine, which is used worldwide, generates both long-lasting neutralizing antibodies and strong T-cell responses. However, on rare occasions, this vaccine has toxic side effects that can be fatal. This study presents the design of two non-viral DNA-based antigen formulations and the characterization of their expression and immunological properties. The two antigen formulations consist of DNA encoding the full-length envelope protein (p/YFE) or the full-length envelope protein fused to the lysosomal-associated membrane protein signal, LAMP-1 (pL/YFE), aimed at diverting antigen processing/presentation through the major histocompatibility complex II precursor compartments. The immune responses triggered by these formulations were evaluated in H2b and H2d backgrounds, corresponding to the C57Bl/6 and BALB/c mice strains, respectively. Both DNA constructs were able to induce very strong T-cell responses of similar magnitude against almost all epitopes that are also generated by the YF 17DD vaccine. The pL/YFE formulation performed best overall. In addition to the T-cell response, it was also able to stimulate high titers of anti-YF neutralizing antibodies comparable to the levels elicited by the 17DD vaccine. More importantly, the pL/YFE vaccine conferred 100% protection against the YF virus in intracerebrally challenged mice. These results indicate that pL/YFE DNA is an excellent vaccine candidate and should be considered for further developmental studies.

  4. A DNA Vaccine against Yellow Fever Virus: Development and Evaluation

    Science.gov (United States)

    Maciel, Milton; Cruz, Fábia da Silva Pereira; Cordeiro, Marli Tenório; da Motta, Márcia Archer; Cassemiro, Klécia Marília Soares de Melo; Maia, Rita de Cássia Carvalho; de Figueiredo, Regina Célia Bressan Queiroz; Galler, Ricardo; Freire, Marcos da Silva; August, Joseph Thomas; Marques, Ernesto T. A.; Dhalia, Rafael

    2015-01-01

    Attenuated yellow fever (YF) virus 17D/17DD vaccines are the only available protection from YF infection, which remains a significant source of morbidity and mortality in the tropical areas of the world. The attenuated YF virus vaccine, which is used worldwide, generates both long-lasting neutralizing antibodies and strong T-cell responses. However, on rare occasions, this vaccine has toxic side effects that can be fatal. This study presents the design of two non-viral DNA-based antigen formulations and the characterization of their expression and immunological properties. The two antigen formulations consist of DNA encoding the full-length envelope protein (p/YFE) or the full-length envelope protein fused to the lysosomal-associated membrane protein signal, LAMP-1 (pL/YFE), aimed at diverting antigen processing/presentation through the major histocompatibility complex II precursor compartments. The immune responses triggered by these formulations were evaluated in H2b and H2d backgrounds, corresponding to the C57Bl/6 and BALB/c mice strains, respectively. Both DNA constructs were able to induce very strong T-cell responses of similar magnitude against almost all epitopes that are also generated by the YF 17DD vaccine. The pL/YFE formulation performed best overall. In addition to the T-cell response, it was also able to stimulate high titers of anti-YF neutralizing antibodies comparable to the levels elicited by the 17DD vaccine. More importantly, the pL/YFE vaccine conferred 100% protection against the YF virus in intracerebrally challenged mice. These results indicate that pL/YFE DNA is an excellent vaccine candidate and should be considered for further developmental studies. PMID:25875109

  5. Menkes' disease in Mottled mice and man

    International Nuclear Information System (INIS)

    Hamer, C.J.A. van den; Prins, H.W.; Nooijen, J.L.

    1979-01-01

    Biochemically the defect of the Brindled allelic mutant of the Mottled mouse and of Menkes' disease in man are very similar if not identical. A modification of a normal Cu-binding protein or an unrestrained synthesis of a Cu-binding protein that normally is present only in small amounts is proposed as the basis of this disease

  6. A simple, rapid and inexpensive method for localization of Tomato yellow leaf curl virus and Potato leafroll virus in plant and insect vectors.

    Science.gov (United States)

    Ghanim, Murad; Brumin, Marina; Popovski, Smadar

    2009-08-01

    A simple, rapid, inexpensive method for the localization of virus transcripts in plant and insect vector tissues is reported here. The method based on fluorescent in situ hybridization using short DNA oligonucleotides complementary to an RNA segment representing a virus transcript in the infected plant or insect vector. The DNA probe harbors a fluorescent molecule at its 5' or 3' ends. The protocol: simple fixation, hybridization, minimal washing and confocal microscopy, provides a highly specific signal. The reliability of the protocol was tested by localizing two phloem-limited plant virus transcripts in infected plants and insect tissues: Tomato yellow leaf curl virus (TYLCV) (Begomovirus: Geminiviridae), exclusively transmitted by the whitefly Bemisia tabaci (Gennadius) in a circulative non-propagative manner, and Potato leafroll virus (Polerovirus: Luteoviridae), similarly transmitted by the aphid Myzus persicae (Sulzer). Transcripts for both viruses were localized specifically to the phloem sieve elements of infected plants, while negative controls showed no signal. TYLCV transcripts were also localized to the digestive tract of B. tabaci, confirming TYLCV route of transmission. Compared to previous methods for localizing virus transcripts in plant and insect tissues that include complex steps for in-vitro probe preparation or antibody raising, tissue fixation, block preparation, sectioning and hybridization, the method described below provides very reliable, convincing, background-free results with much less time, effort and cost.

  7. Partial characterization of the lettuce infectious yellows virus genomic RNAs, identification of the coat protein gene and comparison of its amino acid sequence with those of other filamentous RNA plant viruses.

    Science.gov (United States)

    Klaassen, V A; Boeshore, M; Dolja, V V; Falk, B W

    1994-07-01

    Purified virions of lettuce infectious yellows virus (LIYV), a tentative member of the closterovirus group, contained two RNAs of approximately 8500 and 7300 nucleotides (RNAs 1 and 2 respectively) and a single coat protein species with M(r) of approximately 28,000. LIYV-infected plants contained multiple dsRNAs. The two largest were the correct size for the replicative forms of LIYV virion RNAs 1 and 2. To assess the relationships between LIYV RNAs 1 and 2, cDNAs corresponding to the virion RNAs were cloned. Northern blot hybridization analysis showed no detectable sequence homology between these RNAs. A partial amino acid sequence obtained from purified LIYV coat protein was found to align in the most upstream of four complete open reading frames (ORFs) identified in a LIYV RNA 2 cDNA clone. The identity of this ORF was confirmed as the LIYV coat protein gene by immunological analysis of the gene product expressed in vitro and in Escherichia coli. Computer analysis of the LIYV coat protein amino acid sequence indicated that it belongs to a large family of proteins forming filamentous capsids of RNA plant viruses. The LIYV coat protein appears to be most closely related to the coat proteins of two closteroviruses, beet yellows virus and citrus tristeza virus.

  8. Yellow fever vaccine-associated neurological disease, a suspicious case.

    Science.gov (United States)

    Beirão, Pedro; Pereira, Patrícia; Nunes, Andreia; Antunes, Pedro

    2017-03-02

    A 70-year-old man with known cardiovascular risk factors, presented with acute onset expression aphasia, agraphia, dyscalculia, right-left disorientation and finger agnosia, without fever or meningeal signs. Stroke was thought to be the cause, but cerebrovascular disease investigation was negative. Interviewing the family revealed he had undergone yellow fever vaccination 18 days before. Lumbar puncture revealed mild protein elevation. Cultural examinations, Coxiella burnetti, and neurotropic virus serologies were negative. Regarding the yellow fever virus, IgG was identified in serum and cerebrospinal fluid (CSF), with negative IgM and virus PCR in CSF. EEG showed an encephalopathic pattern. The patient improved gradually and a week after discharge was his usual self. Only criteria for suspect neurotropic disease were met, but it's possible the time spent between symptom onset and lumbar puncture prevented a definite diagnosis of yellow fever vaccine-associated neurological disease. This gap would have been smaller if the vaccination history had been collected earlier. 2017 BMJ Publishing Group Ltd.

  9. evaluation of rice cultivars for resistance to rice yellow mottle virus

    African Journals Online (AJOL)

    ACSS

    2018-02-08

    Feb 8, 2018 ... La variété IR64 s'est avérée sensible à tous les isolats tandis que Tog5681 s'est montré résistant à .... samples ground in phosphate buffer at pH 7.2. (10 ml g-1 of leaf ..... Comparison of molecular and immunological typing of ...

  10. Back-transmission of a virus associated with apple stem pitting and pear vein yellows from Nicotiana occidentalis to apple and pear indicators

    NARCIS (Netherlands)

    Leone, G.; Lindner, J.L.; Jongedijk, G.; Meer, van der F.

    1995-01-01

    The successful back-transmission of the mechanically transmissible virus associated with apple stem pitting and pear vein yellows, from Nicotiana occidentalis to apple seedlings "Golden Delicious" under greenhouse conditions is reported. This result enabled a field experiment where isolates of apple

  11. Global emergence of Zika virus

    Directory of Open Access Journals (Sweden)

    Richard Tjan

    2016-05-01

    Full Text Available Zika virus (ZIKV belongs to the flaviviruses (family Flaviviridae, which includes dengue, yellow fever, West Nile, and Japanese encephalitis viruses. Zika virus was isolated in 1947, in the Zika forest near Kampala, Uganda, from one of the rhesus monkeys used as sentinel animals in a yellow fever research program.

  12. LABORATORY CULTURE METHODS FOR THE MOTTLED SCULPIN (COTTUS BAIRDI)

    Science.gov (United States)

    Fish from the family Cottidae (Sculpin Family) are being researched to determine their sensitivity to various metals in freshwater systems. The ability to culture them in the lab would facilitate species sensitivity comparisons. We collected adult mottled sculpins (C. bairdi) f...

  13. T cell Receptor Alpha Variable 12-2 bias in the immunodominant response to Yellow fever virus

    OpenAIRE

    Bovay, Amandine; Zoete, Vincent; Dolton, Garry; Bulek, Anna M.; Cole, David K.; Rizkallah, Pierre J.; Fuller, Anna; Beck, Konrad; Michielin, Olivier; Speiser, Daniel E.; Sewell, Andrew K.; Fuertes Marraco, Silvia A.

    2018-01-01

    The repertoire of human αβ T-cell receptors (TCRs) is generated via somatic recombination of germline gene segments. Despite this enormous variation, certain epitopes can be immunodominant, associated with high frequencies of antigen-specific T cells and/or exhibit bias toward a TCR gene segment. Here, we studied the TCR repertoire of the HLA-A*0201-restricted epitope LLWNGPMAV (hereafter, A2/LLW) from Yellow Fever virus, which generates an immunodominant CD8 javax.xml.bind.JAXBElement@714aac...

  14. Molecular characterization and phylogenetic analysis of Sugarcane yellow leaf virus isolates from China.

    Science.gov (United States)

    Gao, San-Ji; Lin, Yi-Hua; Pan, Yong-Bao; Damaj, Mona B; Wang, Qin-Nan; Mirkov, T Erik; Chen, Ru-Kai

    2012-10-01

    Sugarcane yellow leaf virus (SCYLV) (genus Polerovirus, family Luteoviridae), the causal agent of sugarcane yellow leaf disease (YLD), was first detected in China in 2006. To assess the distribution of SCYLV in the major sugarcane-growing Chinese provinces, leaf samples from 22 sugarcane clones (Saccharum spp. hybrid) showing YLD symptoms were collected and analyzed for infection by the virus using reverse transcription PCR (RT-PCR), quantitative RT-PCR, and immunological assays. A complete genomic sequence (5,879 nt) of the Chinese SCYLV isolate CHN-FJ1 and partial genomic sequences (2,915 nt) of 13 other Chinese SCYLV isolates from this study were amplified, cloned, and sequenced. The genomic sequence of the CHN-FJ1 isolate was found to share a high identity (98.4-99.1 %) with those of the Brazilian (BRA) genotype isolates and a low identity (86.5-86.9 %) with those of the CHN1 and Cuban (CUB) genotype isolates. The genetic diversity of these 14 Chinese SCYLV isolates was assessed along with that of 29 SCYLV isolates of worldwide origin reported in the GenBank database, based on the full or partial genomic sequence. Phylogenetic analysis demonstrated that all the 14 Chinese SCYLV isolates clustered into one large group with the BRA genotype and 12 other reported SCYLV isolates. In addition, five reported Chinese SCYLV isolates were grouped with the Peruvian (PER), CHN1 and CUB genotypes. We therefore speculated that at least four SCYLV genotypes, BRA, PER, CHN1, and CUB, are associated with YLD in China. Interestingly, a 39-nt deletion was detected in the sequence of the CHN-GD3 isolate, in the middle of the ORF1 region adjacent to the overlap between ORF1 and ORF2. This location is known to be one of the recombination breakpoints in the Luteoviridae family.

  15. Development of transgenic watermelon resistant to Cucumber mosaic virus and Watermelon mosaic virus by using a single chimeric transgene construct.

    Science.gov (United States)

    Lin, Ching-Yi; Ku, Hsin-Mei; Chiang, Yi-Hua; Ho, Hsiu-Yin; Yu, Tsong-Ann; Jan, Fuh-Jyh

    2012-10-01

    Watermelon, an important fruit crop worldwide, is prone to attack by several viruses that often results in destructive yield loss. To develop a transgenic watermelon resistant to multiple virus infection, a single chimeric transgene comprising a silencer DNA from the partial N gene of Watermelon silver mottle virus (WSMoV) fused to the partial coat protein (CP) gene sequences of Cucumber mosaic virus (CMV), Cucumber green mottle mosaic virus (CGMMV) and Watermelon mosaic virus (WMV) was constructed and transformed into watermelon (cv. Feeling) via Agrobacterium-mediated transformation. Single or multiple transgene copies randomly inserted into various locations in the genome were confirmed by Southern blot analysis. Transgenic watermelon R(0) plants were individually challenged with CMV, CGMMV or WMV, or with a mixture of these three viruses for resistance evaluation. Two lines were identified to exhibit resistance to CMV, CGMMV, WMV individually, and a mixed inoculation of the three viruses. The R(1) progeny of the two resistant R(0) lines showed resistance to CMV and WMV, but not to CGMMV. Low level accumulation of transgene transcripts in resistant plants and small interfering (si) RNAs specific to CMV and WMV were readily detected in the resistant R(1) plants by northern blot analysis, indicating that the resistance was established via RNA-mediated post-transcriptional gene silencing (PTGS). Loss of the CGMMV CP-transgene fragment in R1 progeny might be the reason for the failure to resistant CGMMV infection, as shown by the absence of a hybridization signal and no detectable siRNA specific to CGMMV in Southern and northern blot analyses. In summary, this study demonstrated that fusion of different viral CP gene fragments in transgenic watermelon contributed to multiple virus resistance via PTGS. The construct and resistant watermelon lines developed in this study could be used in a watermelon breeding program for resistance to multiple viruses.

  16. The early use of yellow fever virus strain 17D for vaccine production in Brazil - a review

    Directory of Open Access Journals (Sweden)

    Paulo Roberto Post

    2001-08-01

    Full Text Available The use of yellow fever (YF virus 17D strain for vaccine production adapted in Brazil since its introduction in 1937 was reviewed. This was possible due to the availability of official records of vaccine production. The retrieved data highlight the simultaneous use of several serially passaged 17D substrain viruses for both inocula and vaccine preparation that allowed uninterrupted production. Substitution of these substrain viruses became possible with the experience gained during quality control and human vaccination. Post-vaccinal complications in humans and the failure of some viruses in quality control tests (neurovirulence for monkeys indicated that variables needed to be reduced during vaccine production, leading to the development of the seed lot system. The 17DD substrain, still used today, was the most frequently used substrain and the most reliable in terms of safety and efficacy. For this reason, it is possible to derive an infectious cDNA clone of this substrain combined with production in cell culture that could be used to direct the expression of heterologous antigens and lead to the development of new live vaccines.

  17. Empty Turnip yellow mosaic virus capsids as delivery vehicles to mammalian cells.

    Science.gov (United States)

    Kim, Doyeong; Lee, Younghee; Dreher, Theo W; Cho, Tae-Ju

    2018-05-03

    Turnip yellow mosaic virus (TYMV) was able to enter animal cells when the spherical plant virus was conjugated with Tat, a cell penetrating peptide (CPP). Tat was chemically attached to the surface lysine residues of TYMV using hydrazone chemistry. Baby hamster kidney (BHK) cells were incubated with either unmodified or Tat-conjugated TYMV and examined by flow cytometry and confocal microscopic analyses. Tat conjugation was shown to be more efficient than Lipofectamine in allowing TYMV to enter the mammalian cells. Tat-assisted-transfection was also associated with less loss of cell viability than lipofection. Among the CPPs tested (Tat, R8, Pep-1 and Pen), it was observed that R8 and Pen were also effective while Pep-1 was not. We also examined if the internal space of TYMV can be used to load fluorescein dye as a model cargo. When TYMV is treated by freezing and thawing, the virus is known to convert into a structure with a 6-8 nm hole and release viral RNA. When the resultant pot-like particles were reacted with fluorescein-5-maleimide using interior sulfhydryl groups as conjugation sites, about 145 fluorescein molecules were added per particle. The fluorescein-loaded TYMV particles were conjugated with Tat and introduced into BHK cells, again with higher transfection efficiency compared to lipofection. Our studies demonstrate the potential of modified TYMV as an efficient system for therapeutic cargo delivery to mammalian cells. Copyright © 2018 Elsevier B.V. All rights reserved.

  18. Genome sequence variation in the constricta strain dramatically alters the protein interaction and localization map of Potato yellow dwarf virus

    Science.gov (United States)

    The genome sequence of the constricta strain of Potato yellow dwarf virus (CYDV) was determined to be 12,792 nucleotides long and organized into seven open reading frames with the gene order 3’-N-X-P-Y-M-G-L-5’, which encodes the nucleocapsid, phosphoprotein, movement, matrix, glycoprotein and RNA-d...

  19. Quantitative studies on resistance to Polymyxa betae and beet necrotic yellow vein virus in beet = Kwantitatief onderzoek naar resistentie tegen Polymyxa betae en het bieterhizomanievirus in de biet

    NARCIS (Netherlands)

    Paul, H.

    1993-01-01

    Beet necrotic yellow vein virus (BNYVV) causes rhizomania in sugar beet. The virus is transmitted by the soil-borne fungus Polymyxa betae . Rhizomania in sugar beet can cause serious losses in sugar yield. Breeding for resistance is the most promising way to control the

  20. Simultaneous detection and differentiation of three genotypes of Brassica yellows virus by multiplex reverse transcription-polymerase chain reaction.

    Science.gov (United States)

    Zhang, Xiaoyan; Peng, Yanmei; Wang, Ying; Zhang, Zongying; Li, Dawei; Yu, Jialin; Han, Chenggui

    2016-11-22

    Brassica yellows virus (BrYV), proposed to be a new polerovirus species, three distinct genotypes (BrYV-A, BrYV-B and BrYV-C) have been described. This study was to develop a simple, rapid, sensitive, cost-effective method for simultaneous detection and differentiation of three genotypes of BrYV. In this study, a multiplex reverse transcription-polymerase chain reaction (mRT-PCR) was developed for simultaneous detection and differentiation of the three genotypes of BrYV. The three genotypes of BrYV and Tunip yellows virus (TuYV) could be differentiated simultaneously using six optimized specific oligonucleotide primers, including one universal primer for detecting BrYV, three BrYV genotype-specific primers, and a pair of primers for specific detection of TuYV. Primers were designed from conserved regions of each virus and their specificity was confirmed by sequencing PCR products. The mRT-PCR products were 278 bp for BrYV-A, 674 bp for BrYV-B, 505 bp for BrYV-C, and 205 bp for TuYV. Amplification of three target genotypes was optimized by increasing the PCR annealing temperatures to 62 °C. One to three fragments specific for the virus genotypes were simultaneously amplified from infected samples and identified by their specific molecular sizes in agarose gel electrophoresis. No specific products could be amplified from cDNAs of other viruses which could infect crucifer crops. Detection limits of the plasmids for multiplex PCR were 100 fg for BrYV-A and BrYV-B, 10 pg for BrYV-C, and 1 pg for TuYV, respectively. The mRT-PCR was applied successfully for detection of three BrYV genotypes from field samples collected in China. The simple, rapid, sensitive, and cost-effective mRT-PCR was developed successfully for detection and differentiation of the three genotypes of BrYV.

  1. effects of serial planting of seed yam tubers on virus incidence and ...

    African Journals Online (AJOL)

    USER

    FCT) were used in the study. Harvested seed yams were tested for Yam mosaic virus (YMV), Yam mild mottle .... free yam leaves were used for the negative control, while extracts from ..... Development of farmer based seed systems for healthy ...

  2. Complete sequence and diversity of a maize-associated Polerovirus in East Africa.

    Science.gov (United States)

    Massawe, Deogracious P; Stewart, Lucy R; Kamatenesi, Jovia; Asiimwe, Theodore; Redinbaugh, Margaret G

    2018-06-01

    Since 2011-2012, Maize lethal necrosis (MLN) has emerged in East Africa, causing massive yield loss and propelling research to identify viruses and virus populations present in maize. As expected, next generation sequencing (NGS) has revealed diverse and abundant viruses from the family Potyviridae, primarily sugarcane mosaic virus (SCMV), and maize chlorotic mottle virus (MCMV) (Tombusviridae), which are known to cause MLN by synergistic co-infection. In addition to these expected viruses, we identified a virus in the genus Polerovirus (family Luteoviridae) in 104/172 samples selected for MLN or other potential virus symptoms from Kenya, Uganda, Rwanda, and Tanzania. This polerovirus (MF974579) nucleotide sequence is 97% identical to maize-associated viruses recently reported in China, termed 'maize yellow mosaic virus' (MaYMV) and maize yellow dwarf virus (MaYMV; KU291101, KU291107, MYDV-RMV2; KT992824); and 99% identical to MaYMV (KY684356) infecting sugarcane and itch grass in Nigeria; 83% identical to a barley-associated polerovirus recently identified in Korea (BVG; KT962089); and 79% identical to the U.S. maize-infecting polerovirus maize yellow dwarf virus (MYDV-RMV; KT992824). Nucleotide sequences from ORF0 of 20 individual East African isolates collected from Kenya, Uganda, Rwanda, and Tanzania shared 98% or higher identity, and were detected in 104/172 (60.5%) of samples collected for virus-like symptoms, indicating extensive prevalence but limited diversity of this virus in East Africa. We refer to this virus as "MYDV-like polerovirus" until symptoms of the virus in maize are known.

  3. Detection and molecular characterization of tomato yellow leaf curl virus naturally infecting Lycopersicon esculentum in Egypt.

    Science.gov (United States)

    Rabie, M; Ratti, C; Abdel Aleem, E; Fattouh, F

    Tomato yellow leaf curl virus (TYLCV) infections of tomato crops in Egypt were widely spread in 2014. Infected symptomatic tomato plants from different governorates were sampled. TYLCV strains Israel and Mild (TYLCV-IL, TYLCV-Mild) were identified by multiplex and real-time PCR. In addition, nucleotide sequence analysis of the V1 and V2 protein genes, revealed ten TYLCV Egyptian isolates (TYLCV from TY1 to 10). Phylogenetic analysis showed their high degree of relatedness with TYLCV-IL Jordan isolate (98%). Here we have showed the complete nucleotide sequence of the TYLCV Egyptian isolate TY10, sampled from El Beheira. A high degree of similarity to other previously reported Egyptian isolates and isolates from Jordan and Japan reflect the importance of phylogenetic analysis in monitoring virus genetic diversity and possibilities for divergence of more virulent strains or genotypes.

  4. Current status, challenges and perspectives in the development of vaccines against yellow fever, dengue, Zika and chikungunya viruses.

    Science.gov (United States)

    Silva, José V J; Lopes, Thaísa R R; Oliveira-Filho, Edmilson F de; Oliveira, Renato A S; Durães-Carvalho, Ricardo; Gil, Laura H V G

    2018-06-01

    Emerging and re-emerging viral infections transmitted by insect vectors (arthopode-borne viruses, arbovirus) are a serious threat to global public health. Among them, yellow fever (YFV), dengue (DENV), chikungunya (CHIKV) and Zika (ZIKV) viruses are particularly important in tropical and subtropical regions. Although vector control is one of the most used prophylactic measures against arboviruses, it often faces obstacles, such as vector diversity, uncontrolled urbanization and increasing resistance to insecticides. In this context, vaccines may be the best control strategy for arboviral diseases. Here, we provide a general overview about licensed vaccines and the most advanced vaccine candidates against YFV, DENV, CHIKV and ZIKV. In particular, we highlight vaccine difficulties, the current status of the most advanced strategies and discuss how the molecular characteristics of each virus can influence the choice of the different vaccine formulations. Copyright © 2018 Elsevier B.V. All rights reserved.

  5. Classification of cryo electron microscopy images, noisy tomographic images recorded with unknown projection directions, by simultaneously estimating reconstructions and application to an assembly mutant of Cowpea Chlorotic Mottle Virus and portals of the bacteriophage P22

    Science.gov (United States)

    Lee, Junghoon; Zheng, Yili; Yin, Zhye; Doerschuk, Peter C.; Johnson, John E.

    2010-08-01

    Cryo electron microscopy is frequently used on biological specimens that show a mixture of different types of object. Because the electron beam rapidly destroys the specimen, the beam current is minimized which leads to noisy images (SNR substantially less than 1) and only one projection image per object (with an unknown projection direction) is collected. For situations where the objects can reasonably be described as coming from a finite set of classes, an approach based on joint maximum likelihood estimation of the reconstruction of each class and then use of the reconstructions to label the class of each image is described and demonstrated on two challenging problems: an assembly mutant of Cowpea Chlorotic Mottle Virus and portals of the bacteriophage P22.

  6. Plasmid DNA initiates replication of yellow fever vaccine in vitro and elicits virus-specific immune response in mice.

    Science.gov (United States)

    Tretyakova, Irina; Nickols, Brian; Hidajat, Rachmat; Jokinen, Jenny; Lukashevich, Igor S; Pushko, Peter

    2014-11-01

    Yellow fever (YF) causes an acute hemorrhagic fever disease in tropical Africa and Latin America. To develop a novel experimental YF vaccine, we applied iDNA infectious clone technology. The iDNA represents plasmid that encodes the full-length RNA genome of 17D vaccine downstream from a cytomegalovirus (CMV) promoter. The vaccine was designed to transcribe the full-length viral RNA and to launch 17D vaccine virus in vitro and in vivo. Transfection with 10 ng of iDNA plasmid was sufficient to start replication of vaccine virus in vitro. Safety of the parental 17D and iDNA-derived 17D viruses was confirmed in AG129 mice deficient in receptors for IFN-α/β/γ. Finally, direct vaccination of BALB/c mice with a single 20 μg dose of iDNA plasmid resulted in seroconversion and elicitation of virus-specific neutralizing antibodies in animals. We conclude that iDNA immunization approach combines characteristics of DNA and attenuated vaccines and represents a promising vaccination strategy for YF. Copyright © 2014 Elsevier Inc. All rights reserved.

  7. Development of a membrane adsorber based capture step for the purification of yellow fever virus.

    Science.gov (United States)

    Pato, Tânia P; Souza, Marta Cristina O; Silva, Andréa N M R; Pereira, Renata C; Silva, Marlon V; Caride, Elena; Gaspar, Luciane P; Freire, Marcos S; Castilho, Leda R

    2014-05-19

    Yellow fever (YF) is an endemic disease in some tropical areas of South America and Africa that presents lethality rate between 20 and 50%. There is no specific treatment and to control this disease a highly effective live-attenuated egg based vaccine is widely used for travelers and residents of areas where YF is endemic. However, recent reports of rare, sometimes fatal, adverse events post-vaccination have raised concerns. In order to increase safety records, alternative strategies should be considered, such as developing a new inactivated vaccine using a cell culture based technology, capable of meeting the demands in cases of epidemic. With this goal, the production of YF virus in Vero cells grown on microcarriers and its subsequent purification by chromatographic techniques was studied. In this work we investigate the capture step of the purification process of the YF virus. At first, virus stability was studied over a wide pH range, showing best results for the alkaline region. Considering this result and the pI of the envelope protein previously determined in silico, a strong anion exchanger was considered most suitable. Due to the easy scalability, simplicity to handle, absence of diffusional limitations and suitability for virus handling of membrane adsorbers, a Q membrane was evaluated. The amount of antigen adsorbed onto the membrane was investigated within the pH range for virus stability, and the best pH for virus adsorption was considered to be 8.5. Finally, studies on gradient and step elution allowed to determine the most adequate salt concentration for washing (0.15M) and virus elution (0.30 M). Under these operating conditions, it was shown that this capture step is quite efficient, showing high product recovery (93.2±30.3%) and efficient DNA clearance (0.9±0.3 ng/dose). Copyright © 2014 Elsevier Ltd. All rights reserved.

  8. Yellow Fever Outbreak - Kongo Central Province, Democratic Republic of the Congo, August 2016.

    Science.gov (United States)

    Otshudiema, John O; Ndakala, Nestor G; Mawanda, Elande-Taty K; Tshapenda, Gaston P; Kimfuta, Jacques M; Nsibu, Loupy-Régence N; Gueye, Abdou S; Dee, Jacob; Philen, Rossanne M; Giese, Coralie; Murrill, Christopher S; Arthur, Ray R; Kebela, Benoit I

    2017-03-31

    On April 23, 2016, the Democratic Republic of the Congo's (DRC's) Ministry of Health declared a yellow fever outbreak. As of May 24, 2016, approximately 90% of suspected yellow fever cases (n = 459) and deaths (45) were reported in a single province, Kongo Central Province, that borders Angola, where a large yellow fever outbreak had begun in December 2015. Two yellow fever mass vaccination campaigns were conducted in Kongo Central Province during May 25-June 7, 2016 and August 17-28, 2016. In June 2016, the DRC Ministry of Health requested assistance from CDC to control the outbreak. As of August 18, 2016, a total of 410 suspected yellow fever cases and 42 deaths were reported in Kongo Central Province. Thirty seven of the 393 specimens tested in the laboratory were confirmed as positive for yellow fever virus (local outbreak threshold is one laboratory-confirmed case of yellow fever). Although not well-documented for this outbreak, malaria, viral hepatitis, and typhoid fever are common differential diagnoses among suspected yellow fever cases in this region. Other possible diagnoses include Zika, West Nile, or dengue viruses; however, no laboratory-confirmed cases of these viruses were reported. Thirty five of the 37 cases of yellow fever were imported from Angola. Two-thirds of confirmed cases occurred in persons who crossed the DRC-Angola border at one market city on the DRC side, where ≤40,000 travelers cross the border each week on market day. Strategies to improve coordination between health surveillance and cross-border trade activities at land borders and to enhance laboratory and case-based surveillance and health border screening capacity are needed to prevent and control future yellow fever outbreaks.

  9. Genome characterization of sugarcane yellow leaf virus from China reveals a novel recombinant genotype.

    Science.gov (United States)

    Lin, Yi-Hua; Gao, San-Ji; Damaj, Mona B; Fu, Hua-Ying; Chen, Ru-Kai; Mirkov, T Erik

    2014-06-01

    Sugarcane yellow leaf virus (SCYLV; genus Polerovirus, family Luteoviridae) is a recombinant virus associated with yellow leaf disease, a serious threat to sugarcane in China and worldwide. Among the nine known SCYLV genotypes existing worldwide, COL, HAW, REU, IND, CHN1, CHN2, BRA, CUB and PER, the last five have been reported in China. In this study, the complete genome sequences (5,880 nt) of GZ-GZ18 and HN-CP502 isolates from the Chinese provinces of Guizhou and Hainan, respectively, were cloned, sequenced and characterized. Phylogenetic analysis showed that, among 29 SCYLV isolates described worldwide, the two Chinese isolates clustered together into an independent clade based on the near-complete genome nucleotide (ORF0-ORF5) or amino acid sequences of individual genes, except for the MP protein (ORF4). We propose that the two isolates represent a novel genotype, CHN3, diverging from other genotypes by 1.7-13.6 % nucleotide differences in ORF0-ORF5, and 2.7-28.1 %, 1.8-20.4 %, 0.5-5.1 % and 2.7-15.9 % amino acid differences in P0 (ORF0), RdRp (RNA-dependent RNA polymerase) (ORF1+2), CP (coat protein) (ORF3) and RT (readthrough protein) (ORF3+5), respectively. CHN3 was closely related to the BRA, HAW and PER genotypes, differing by 1.7-3.8 % in the near-complete genome nucleotide sequence. Recombination analysis further identified CHN3 as a new recombinant strain, arising from the major parent CHN-HN1 and the minor parent CHN-GD-WY19. Recombination breakpoints were distributed mostly within the RdRp region in CHN3 and the four significant recombinant genotypes, IND, REU, CUB and BRA. Recombination is considered to contribute significantly to the evolution and emergence of such new SCYLV variants.

  10. The 3' untranslated region of tobacco necrosis virus RNA contains a barley yellow dwarf virus-like cap-independent translation element.

    Science.gov (United States)

    Shen, Ruizhong; Miller, W Allen

    2004-05-01

    RNAs of many viruses are translated efficiently in the absence of a 5' cap structure. The tobacco necrosis virus (TNV) genome is an uncapped, nonpolyadenylated RNA whose translation mechanism has not been well investigated. Computational analysis predicted a cap-independent translation element (TE) within the 3' untranslated region (3' UTR) of TNV RNA that resembles the TE of barley yellow dwarf virus (BYDV), a luteovirus. Here we report that such a TE does indeed exist in the 3' UTR of TNV strain D. Like the BYDV TE, the TNV TE (i) functions both in vitro and in vivo, (ii) requires additional sequence for cap-independent translation in vivo, (iii) has a similar secondary structure and the conserved sequence CGGAUCCUGGGAAACAGG, (iv) is inactivated by a four-base duplication in this conserved sequence, (v) can function in the 5' UTR, and (vi) when located in its natural 3' location, may form long-distance base pairing with the viral 5' UTR that is conserved and probably required. The TNV TE differs from the BYDV TE by having only three helical domains instead of four. Similar structures were found in all members of the Necrovirus genus of the Tombusviridae family, except satellite tobacco necrosis virus, which harbors a different 3' cap-independent translation domain. The presence of the BYDV-like TE in select genera of different families indicates that phylogenetic distribution of TEs does not follow standard viral taxonomic relationships. We propose a new class of cap-independent TE called BYDV-like TE.

  11. Investigation of a possible yellow fever epidemic and serosurvey for flavivirus infections in northern Cameroon, 1984.

    Science.gov (United States)

    Tsai, T F; Lazuick, J S; Ngah, R W; Mafiamba, P C; Quincke, G; Monath, T P

    1987-01-01

    A cluster of fatal hepatitis cases in northern Cameroon in 1984 stimulated a field investigation to rule out an epidemic of yellow fever. A serosurvey of villages in the extreme north of the country, in a Sudan savanna (SS) phytogeographical zone, disclosed no evidence of recent yellow fever infection. However, further south, in a Guinea savanna (GS) phytogeographical zone, serological evidence was found of endemic yellow fever virus transmission. The results indicate a potential for epidemic spread of yellow fever virus from the southern GS zone to the nothern SS zone of Cameroon, where immunity in the population was low.

  12. Tomato yellow vein streak virus: relationship with Bemisia tabaci biotype B and host range Tomato yellow vein streak virus: interação com a Bemisia tabaci biótipo B e gama de hospedeiros

    Directory of Open Access Journals (Sweden)

    Ana Carolina Firmino

    2009-12-01

    Full Text Available The Tomato yellow vein streak virus (ToYVSV is a putative species of begomovirus, which was prevalent on tomato crops in São Paulo State, Brazil, until 2005. The objectives of this study were to evaluate the interaction between ToYVSV and its vector Bemisia tabaci biotype B and to identify alternative hosts for the virus. The minimum acquisition and inoculation access periods of ToYVSV by B. tabaci were 30 min and 10 min, respectively. Seventy five percent of tomato-test plants were infected when the acquisition and inoculation access periods were 24 h. The latent period of the virus in the insect was 16 h. The ToYVSV was retained by B. tabaci until 20 days after acquisition. First generation of adult whiteflies obtained from viruliferous females were virus free as shown by PCR analysis and did not transmit the virus to tomato plants. Out of 34 species of test-plants inoculated with ToYVSV only Capsicum annuum, Chenopodium amaranticolor, C. quinoa, Datura stramonium, Gomphrena globosa, Nicotiana clevelandii and N. tabacum cv. TNN were susceptible to infection. B. tabaci biotype B was able to acquire the virus from all these susceptible species, transmitting it to tomato plants.O Tomato yellow vein streak virus (ToYVSV é uma espécie putativa de begomovirus que infecta o tomateiro (Solanum lycopersicon em diversas regiões do Brasil onde se cultiva essa solanácea, sendo a espécie prevalente no estado de São Paulo até 2005. Estudou-se a interação do ToYVSV com a Bemisia tabaci biótipo B e identificaram-se hospedeiras alternativas deste vírus. Os períodos de acesso mínimo de aquisição (PAA e de inoculação (PAI foram de 30 min e 10 min, respectivamente. A porcentagem de plantas infectadas chegou até cerca de 75% após um PAA e PAI de 24 h. O período de latência do vírus no vetor foi de 16 horas. O ToYVSV foi retido pela B. tabaci até 20 dias após a aquisição do vírus. Não foi detectada transmissão do vírus para prog

  13. Evaluation of a SUMO E2 conjugating enzyme involved in resistance to Clavibacter michiganensis subsp. michiganensis in Solanum peruvianum, through a tomato mottle virus VIGS assay

    Directory of Open Access Journals (Sweden)

    Mayra Janeth Esparza-Araiza

    2015-12-01

    Full Text Available Clavibacter michiganensis subsp. michiganensis (Cmm causes bacterial wilt and canker of tomato. Currently, no Solanum lycopersicum resistant varieties are commercially available, but some degree of Cmm resistance has been identified in Solanum peruvianum. Previous research showed up-regulation of a SUMO E2 conjugating enzyme (SCEI transcript in resistant S. peruvianum compared to susceptible S. lycopersicum following infection by Cmm. In order to test the role of SCEI in resistance to Cmm, a fragment of the gene from S. peruvianum was cloned into a novel virus-induced gene-silencing (VIGS vector based on the geminivirus Tomato Mottle Virus (ToMoV. Using biolistic inoculation, the ToMoV-based VIGS vector was shown to be effective in S. peruvianum by silencing the magnesium chelatase gene, which resulted in leaf bleaching. The ToMoV_SCEI construct resulted in approx. 61% silencing of SCEI in leaves of S. peruvianum as determined by quantitative RT-PCR. VIGS of SCEI in S. peruvianum resulted in unilateral wilting (15 dpi and subsequent death (20 dpi of the entire plant after Cmm inoculation, whereas empty vector-treated plants only showed wilting in the Cmm-inoculated leaf. SCEI-silenced plants also showed higher Cmm colonization with an average of 4.5 times more damaged tissue compared to the empty vector control plants. SCEI appears to play an important role in the innate immunity of S. peruvianum against Cmm, perhaps through the regulation of WRKY transcription factors, which may lead to expression of proteins involved in salicylic acid-dependent defense responses.

  14. Genetic organisation of iris yellow spot virus MRNA: implications for functional homology between the Gc glycoproteins of tospoviruses and animal-infecting bunyaviruses

    NARCIS (Netherlands)

    Cortez, I.; Aires, A.; Pereira, A.M.; Goldbach, R.

    2002-01-01

    Summary. The complete nucleotide sequence (4838 nucleotides) of Iris yellow spot virus (IYSV) M RNA indicates, typical for tospoviruses, the presence of two genes in ambisense arrangement. The vRNA ORF codes for the potential cell-to-cell movement (NSm) protein (34.8 kDa) and the vcRNA ORF for the

  15. Human Leukocyte Antigen (HLA) Class I Restricted Epitope Discovery in Yellow Fewer and Dengue Viruses: Importance of HLA Binding Strength

    DEFF Research Database (Denmark)

    Lund, Ole; Nascimento, Eduardo J. M.; Maciel, Milton, Jr

    2011-01-01

    Epitopes from all available full-length sequences of yellow fever virus (YFV) and dengue fever virus (DENV) restricted by Human Leukocyte Antigen class I (HLA-I) alleles covering 12 HLA-I supertypes were predicted using the NetCTL algorithm. A subset of 179 predicted YFV and 158 predicted DENV...... inoculated twice with the 17DD YFV vaccine strain. Three of the YFV A*02:01 restricted peptides activated T-cells from the infected mice in vitro. All three peptides that elicited responses had an HLA binding affinity of 2 nM or less. The results indicate the importance of the strength of HLA binding...

  16. Diversity and evolutionary history of lettuce necrotic yellows virus in Australia and New Zealand.

    Science.gov (United States)

    Higgins, Colleen M; Chang, Wee-Leong; Khan, Subuhi; Tang, Joe; Elliott, Carol; Dietzgen, Ralf G

    2016-02-01

    Lettuce necrotic yellows virus (LNYV) is the type member of the genus Cytorhabdovirus, family Rhabdoviridae, and causes a severe disease of lettuce (Lactuca sativa L.). This virus has been described as endemic to Australia and New Zealand, with sporadic reports of a similar virus in Europe. Genetic variability studies of plant-infecting rhabdoviruses are scarce. We have extended a previous study on the variability of the LNYV nucleocapsid gene, comparing sequences from isolates sampled from both Australia and New Zealand, as well as analysing symptom expression on Nicotiana glutinosa. Phylogenetic and BEAST analyses confirm separation of LNYV isolates into two subgroups (I and II) and suggest that subgroup I is slightly older than subgroup II. No correlation was observed between isolate subgroup and disease symptoms on N. glutinosa. The origin of LNYV remains unclear; LNYV may have moved between native and weed hosts within Australia or New Zealand before infecting lettuce or may have appeared as a result of at least two incursions, with the first coinciding with the beginning of European agriculture in the region. The apparent extinction of subgroup I in Australia may have been due to less-efficient dispersal than that which has occurred for subgroup II - possibly a consequence of suboptimal interactions with plant and/or insect hosts. Introduction of subgroup II to New Zealand appears to be more recent. More-detailed epidemiological studies using molecular tools are needed to fully understand how LNYV interacts with its hosts and to determine where the virus originated.

  17. Genome-Wide Association Mapping of Barley Yellow Dwarf Virus Tolerance in Spring Oat (Avena sativa L..

    Directory of Open Access Journals (Sweden)

    Bradley J Foresman

    Full Text Available Barley yellow dwarf viruses (BYDVs are responsible for the disease barley yellow dwarf (BYD and affect many cereals including oat (Avena sativa L.. Until recently, the molecular marker technology in oat has not allowed for many marker-trait association studies to determine the genetic mechanisms for tolerance. A genome-wide association study (GWAS was performed on 428 spring oat lines using a recently developed high-density oat single nucleotide polymorphism (SNP array as well as a SNP-based consensus map. Marker-trait associations were performed using a Q-K mixed model approach to control for population structure and relatedness. Six significant SNP-trait associations representing two QTL were found on chromosomes 3C (Mrg17 and 18D (Mrg04. This is the first report of BYDV tolerance QTL on chromosome 3C (Mrg17 and 18D (Mrg04. Haplotypes using the two QTL were evaluated and distinct classes for tolerance were identified based on the number of favorable alleles. A large number of lines carrying both favorable alleles were observed in the panel.

  18. Limited replication of yellow fever 17DD and 17D-Dengue recombinant viruses in rhesus monkeys

    Directory of Open Access Journals (Sweden)

    Gisela F. Trindade

    2008-06-01

    Full Text Available For the development of safe live attenuated flavivirus vaccines one of the main properties to be established is viral replication. We have used real-time reverse transcriptase-polymerase chain reaction and virus titration by plaque assay to determine the replication of yellow fever 17DD virus (YFV 17DD and recombinant yellow fever 17D viruses expressing envelope proteins of dengue virus serotypes 2 and 4 (17D-DENV-2 and 17D-DENV-4. Serum samples from rhesus monkeys inoculated with YFV 17DD and 17D-DENV chimeras by intracerebral or subcutaneous route were used to determine and compare the viremia induced by these viruses. Viral load quantification in samples from monkeys inoculated by either route with YFV 17DD virus suggested a restricted capability of the virus to replicate reaching not more than 2.0 log10 PFU mL-1 or 3.29 log10 copies mL-1. Recombinant 17D-dengue viruses were shown by plaquing and real-time PCR to be as attenuated as YF 17DD virus with the highest mean peak titer of 1.97 log10 PFU mL-1 or 3.53 log10 copies mL-1. These data serve as a comparative basis for the characterization of other 17D-based live attenuated candidate vaccines against other diseases.Uma das principais propriedades a serem estabelecidas para o desenvolvimento de vacinas seguras e atenuadas de flavivirus,é a taxa de replicação viral. Neste trabalho, aplicamos a metodologia de amplificação pela reação em cadeia da polimerase em tempo real e titulação viral por plaqueamento para determinação da replicação do vírus 17DD (FA 17DD e recombinantes, expressando proteínas do envelope de dengue sorotipos 2 e 4 (17D-DENV-2 e 17D-DENV-4. As amostras de soros de macacos inoculados por via intracerebral ou subcutânea com FA 17DD ou 17D-DENV foram usadas para determinar e comparar a viremia induzida por estes vírus. A quantificação da carga viral em amostras de macacos inoculados por ambas as vias com FA 17DD sugere restrita capacidade de replicação com

  19. Formation of virions is strictly required for turnip yellows virus long-distance movement in plants.

    Science.gov (United States)

    Hipper, Clémence; Monsion, Baptiste; Bortolamiol-Bécet, Diane; Ziegler-Graff, Véronique; Brault, Véronique

    2014-02-01

    Viral genomic RNA of the Turnip yellows virus (TuYV; genus Polerovirus; family Luteoviridae) is protected in virions formed by the major capsid protein (CP) and the minor component, the readthrough (RT*) protein. Long-distance transport, used commonly by viruses to systemically infect host plants, occurs in phloem sieve elements and two viral forms of transport have been described: virions and ribonucleoprotein (RNP) complexes. With regard to poleroviruses, virions have always been presumed to be the long-distance transport form, but the potential role of RNP complexes has not been investigated. Here, we examined the requirement of virions for polerovirus systemic movement by analysing CP-targeted mutants that were unable to form viral particles. We confirmed that TuYV mutants that cannot encapsidate into virions are not able to reach systemic leaves. To completely discard the possibility that the introduced mutations in CP simply blocked the formation or the movement of RNP complexes, we tested in trans complementation of TuYV CP mutants by providing WT CP expressed in transgenic plants. WT CP was able to facilitate systemic movement of TuYV CP mutants and this observation was always correlated with the formation of virions. This demonstrated clearly that virus particles are essential for polerovirus systemic movement.

  20. [The fourth horseman: The yellow fever].

    Science.gov (United States)

    Vallejos-Parás, Alfonso; Cabrera-Gaytán, David Alejandro

    2017-01-01

    Dengue virus three, Chikunguya and Zika have entered the national territory through the south of the country. Cases and outbreaks of yellow fever have now been identified in the Americas where it threatens to expand. Although Mexico has a robust epidemiological surveillance system for vector-borne diseases, our country must be alert in case of its possible introduction into the national territory. This paper presents theoretical assumptions based on factual data on the behavior of yellow fever in the Americas, as well as reflections on the epidemiological surveillance of vector-borne diseases.

  1. Efeito do Soursop yellow blotch virus no desenvolvimento vegetativo e na produção da gravioleira

    OpenAIRE

    Santos,Antonio A. dos; Cardoso,José Edmilson; Viana,Francisco Marto Pinto; Vidal,Júlio Cal; Souza,Raimundo Nonato Martins de

    2007-01-01

    Os danos causados no desenvolvimento vegetativo e na produção de frutos da gravioleira pelo vírus da mancha-amarela da gravioleira (Soursop yellow blotch virus, SYBV), foram estudados durante os anos de 2000 a 2004 em um experimento com dois tratamentos: plantas sadias e plantas doentes, dispostos em blocos ao acaso, com oito repetições e quatro plantas por parcela. Foram avaliados, anualmente, a altura da planta, diâmetro do caule, número e peso de frutos, sendo que a produção foi monitorada...

  2. CD8+ T Cells Complement Antibodies in Protecting against Yellow Fever Virus

    DEFF Research Database (Denmark)

    Bassi, Maria R; Kongsgaard, Michael; Steffensen, Maria A

    2015-01-01

    The attenuated yellow fever (YF) vaccine (YF-17D) was developed in the 1930s, yet little is known about the protective mechanisms underlying its efficiency. In this study, we analyzed the relative contribution of cell-mediated and humoral immunity to the vaccine-induced protection in a murine model...... of YF-17D infection. Using different strains of knockout mice, we found that CD4(+) T cells, B cells, and Abs are required for full clinical protection of vaccinated mice, whereas CD8(+) T cells are dispensable for long-term survival after intracerebral challenge. However, by analyzing the immune...... response inside the infected CNS, we observed an accelerated T cell influx into the brain after intracerebral challenge of vaccinated mice, and this T cell recruitment correlated with improved virus control in the brain. Using mice deficient in B cells we found that, in the absence of Abs, YF vaccination...

  3. Serologic assessment of yellow fever immunity in the rural population of a yellow fever-endemic area in Central Brazil

    Directory of Open Access Journals (Sweden)

    Vanessa Wolff Machado

    2013-04-01

    Full Text Available Introduction The yellow fever epidemic that occurred in 1972/73 in Central Brazil surprised the majority of the population unprotected. A clinical-epidemiological survey conducted at that time in the rural area of 19 municipalities found that the highest (13.8% number of disease cases were present in the municipality of Luziânia, State of Goiás. Methods Thirty-eight years later, a new seroepidemiological survey was conducted with the aim of assessing the degree of immune protection of the rural population of Luziânia, following the continuous attempts of public health services to obtain vaccination coverage in the region. A total of 383 volunteers, aged between 5 and 89 years and with predominant rural labor activities (75.5%, were interviewed. The presence of antibodies against the yellow fever was also investigated in these individuals, by using plaque reduction neutralization test, and correlated to information regarding residency, occupation, epidemiological data and immunity against the yellow fever virus. Results We found a high (97.6% frequency of protective titers (>1:10 of neutralizing antibodies against the yellow fever virus; the frequency of titers of 1:640 or higher was 23.2%, indicating wide immune protection against the disease in the study population. The presence of protective immunity was correlated to increasing age. Conclusions This study reinforces the importance of surveys to address the immune state of a population at risk for yellow fever infection and to the surveillance of actions to control the disease in endemic areas.

  4. Reaction of rice cultivars to a virulent Rice Yellow Mottle Virus strain ...

    African Journals Online (AJOL)

    Isolates of RYMV were collected from three “hot-spots” in Uganda (Lira, Luweero and Iganga). The isolate from Iganga was most virulent on RYMV susceptible cultivar (IR64), and thus used to constitute study treatment evaluated in the study. Cultivars were potted and raised in a screenhouse experiment arranged in a ...

  5. Partially resistant Cucurbita pepo showed late onset of the Zucchini yellow mosaic virus infection due to rapid activation of defense mechanisms as compared to susceptible cultivar

    Czech Academy of Sciences Publication Activity Database

    Nováková, S.; Flores-Ramirez, G.; Glasa, M.; Danchenko, M.; Fiala, R.; Škultéty, L'udovít

    2015-01-01

    Roč. 6, APR 2015 (2015), s. 1-14 ISSN 1664-462X Institutional support: RVO:61388971 Keywords : Cucurbita pepo cultivars * Zucchini yellow mosaic virus * resistance to phytopatogen Subject RIV: CE - Biochemistry Impact factor: 4.495, year: 2015

  6. Tripartite interactions of Barley yellow dwarf virus, Sitobion avenae and wheat varieties.

    Directory of Open Access Journals (Sweden)

    Xiao-Feng Liu

    Full Text Available The tripartite interactions in a pathosystem involving wheat (Triticum aestivum L., the Barley yellow dwarf virus (BYDV, and the BYDV vector aphid Sitobion avenae were studied under field conditions to determine the impact of these interactions on aphid populations, virus pathology and grain yield. Wheat varietal resistance to BYDV and aphids varied among the three wheat varieties studied over two consecutive years. The results demonstrated that (1 aphid peak number (APN in the aphid + BYDV (viruliferous aphid treatment was greater and occurred earlier than that in the non-viruliferous aphid treatment. The APN and the area under the curve of population dynamics (AUC on a S. avenae-resistant variety 98-10-30 was significantly lower than on two aphid-susceptible varieties Tam200(13G and Xiaoyan6. (2 The production of alatae (PA was greater on the variety 98-10-30 than on the other varieties, and PA was greater in the aphid + BYDV treatment on 98-10-30 than in the non-viruliferous aphid treatment, but this trend was reversed on Tam200(13G and Xiaoyan6. (3 The BYDV disease incidence (DIC on the variety 98-10-30 was greater than that on the other two varieties in 2012, and the disease index (DID on Tam200(13G was lower than on the other varieties in the aphid + BYDV and BYDV treatments in 2012, but not in 2011 when aphid vector numbers were generally lower. (4 Yield loss in the aphid + BYDV treatment tended to be greater than that in the aphid or BYDV alone treatments across varieties and years. We suggested that aphid population development and BYDV transmission tend to promote each other under field conditions. The aphids + BYDV treatment caused greater yield reductions than non-viruliferous aphids or virus treatment. Wheat varietal resistance in 98-10-30 affects the aphid dispersal, virus transmission and wheat yield loss though inhibits aphid populations from increasing.

  7. Tripartite Interactions of Barley Yellow Dwarf Virus, Sitobion avenae and Wheat Varieties

    Science.gov (United States)

    Liu, Xiao-Feng; Hu, Xiang-Shun; Keller, Mike A.; Zhao, Hui-Yan; Wu, Yun-Feng; Liu, Tong-Xian

    2014-01-01

    The tripartite interactions in a pathosystem involving wheat (Triticum aestivum L.), the Barley yellow dwarf virus (BYDV), and the BYDV vector aphid Sitobion avenae were studied under field conditions to determine the impact of these interactions on aphid populations, virus pathology and grain yield. Wheat varietal resistance to BYDV and aphids varied among the three wheat varieties studied over two consecutive years. The results demonstrated that (1) aphid peak number (APN) in the aphid + BYDV (viruliferous aphid) treatment was greater and occurred earlier than that in the non-viruliferous aphid treatment. The APN and the area under the curve of population dynamics (AUC) on a S. avenae-resistant variety 98-10-30 was significantly lower than on two aphid-susceptible varieties Tam200(13)G and Xiaoyan6. (2) The production of alatae (PA) was greater on the variety 98-10-30 than on the other varieties, and PA was greater in the aphid + BYDV treatment on 98-10-30 than in the non-viruliferous aphid treatment, but this trend was reversed on Tam200(13)G and Xiaoyan6. (3) The BYDV disease incidence (DIC) on the variety 98-10-30 was greater than that on the other two varieties in 2012, and the disease index (DID) on Tam200(13)G was lower than on the other varieties in the aphid + BYDV and BYDV treatments in 2012, but not in 2011 when aphid vector numbers were generally lower. (4) Yield loss in the aphid + BYDV treatment tended to be greater than that in the aphid or BYDV alone treatments across varieties and years. We suggested that aphid population development and BYDV transmission tend to promote each other under field conditions. The aphids + BYDV treatment caused greater yield reductions than non-viruliferous aphids or virus treatment. Wheat varietal resistance in 98-10-30 affects the aphid dispersal, virus transmission and wheat yield loss though inhibits aphid populations from increasing. PMID:25184214

  8. The 3′ Untranslated Region of Tobacco Necrosis Virus RNA Contains a Barley Yellow Dwarf Virus-Like Cap-Independent Translation Element

    Science.gov (United States)

    Shen, Ruizhong; Miller, W. Allen

    2004-01-01

    RNAs of many viruses are translated efficiently in the absence of a 5′ cap structure. The tobacco necrosis virus (TNV) genome is an uncapped, nonpolyadenylated RNA whose translation mechanism has not been well investigated. Computational analysis predicted a cap-independent translation element (TE) within the 3′ untranslated region (3′ UTR) of TNV RNA that resembles the TE of barley yellow dwarf virus (BYDV), a luteovirus. Here we report that such a TE does indeed exist in the 3′ UTR of TNV strain D. Like the BYDV TE, the TNV TE (i) functions both in vitro and in vivo, (ii) requires additional sequence for cap-independent translation in vivo, (iii) has a similar secondary structure and the conserved sequence CGGAUCCUGGGAAACAGG, (iv) is inactivated by a four-base duplication in this conserved sequence, (v) can function in the 5′ UTR, and (vi) when located in its natural 3′ location, may form long-distance base pairing with the viral 5′ UTR that is conserved and probably required. The TNV TE differs from the BYDV TE by having only three helical domains instead of four. Similar structures were found in all members of the Necrovirus genus of the Tombusviridae family, except satellite tobacco necrosis virus, which harbors a different 3′ cap-independent translation domain. The presence of the BYDV-like TE in select genera of different families indicates that phylogenetic distribution of TEs does not follow standard viral taxonomic relationships. We propose a new class of cap-independent TE called BYDV-like TE. PMID:15078948

  9. The synergistic effect of combined immunization with a DNA vaccine and chimeric yellow fever/dengue virus leads to strong protection against dengue.

    Directory of Open Access Journals (Sweden)

    Adriana S Azevedo

    Full Text Available The dengue envelope glycoprotein (E is the major component of virion surface and its ectodomain is composed of domains I, II and III. This protein is the main target for the development of a dengue vaccine with induction of neutralizing antibodies. In the present work, we tested two different vaccination strategies, with combined immunizations in a prime/booster regimen or simultaneous inoculation with a DNA vaccine (pE1D2 and a chimeric yellow fever/dengue 2 virus (YF17D-D2. The pE1D2 DNA vaccine encodes the ectodomain of the envelope DENV2 protein fused to t-PA signal peptide, while the YF17D-D2 was constructed by replacing the prM and E genes from the 17D yellow fever vaccine virus by those from DENV2. Balb/c mice were inoculated with these two vaccines by different prime/booster or simultaneous immunization protocols and most of them induced a synergistic effect on the elicited immune response, mainly in neutralizing antibody production. Furthermore, combined immunization remarkably increased protection against a lethal dose of DENV2, when compared to each vaccine administered alone. Results also revealed that immunization with the DNA vaccine, regardless of the combination with the chimeric virus, induced a robust cell immune response, with production of IFN-γ by CD8+ T lymphocytes.

  10. Identification, Characterization and Full-Length Sequence Analysis of a Novel Polerovirus Associated with Wheat Leaf Yellowing Disease.

    Science.gov (United States)

    Zhang, Peipei; Liu, Yan; Liu, Wenwen; Cao, Mengji; Massart, Sebastien; Wang, Xifeng

    2017-01-01

    To identify the pathogens responsible for leaf yellowing symptoms on wheat samples collected from Jinan, China, we tested for the presence of three known barley/wheat yellow dwarf viruses (BYDV-GAV, -PAV, WYDV-GPV) (most likely pathogens) using RT-PCR. A sample that tested negative for the three viruses was selected for small RNA sequencing. Twenty-five million sequences were generated, among which 5% were of viral origin. A novel polerovirus was discovered and temporarily named wheat leaf yellowing-associated virus (WLYaV). The full genome of WLYaV corresponds to 5,772 nucleotides (nt), with six AUG-initiated open reading frames, one non-AUG-initiated open reading frame, and three untranslated regions, showing typical features of the family Luteoviridae . Sequence comparison and phylogenetic analyses suggested that WLYaV had the closest relationship with sugarcane yellow leaf virus (ScYLV), but the identities of full genomic nucleotides and deduced amino acid sequence of coat protein (CP) were 64.9 and 86.2%, respectively, below the species demarcation thresholds (90%) in the family Luteoviridae . Furthermore, agroinoculation of Nicotiana benthamiana leaves with a cDNA clone of WLYaV caused yellowing symptoms on the plant. Our study adds a new polerovirus that is associated with wheat leaf yellowing disease, which would help to identify and control pathogens of wheat.

  11. Identification, Characterization and Full-Length Sequence Analysis of a Novel Polerovirus Associated with Wheat Leaf Yellowing Disease

    Directory of Open Access Journals (Sweden)

    Peipei Zhang

    2017-09-01

    Full Text Available To identify the pathogens responsible for leaf yellowing symptoms on wheat samples collected from Jinan, China, we tested for the presence of three known barley/wheat yellow dwarf viruses (BYDV-GAV, -PAV, WYDV-GPV (most likely pathogens using RT-PCR. A sample that tested negative for the three viruses was selected for small RNA sequencing. Twenty-five million sequences were generated, among which 5% were of viral origin. A novel polerovirus was discovered and temporarily named wheat leaf yellowing-associated virus (WLYaV. The full genome of WLYaV corresponds to 5,772 nucleotides (nt, with six AUG-initiated open reading frames, one non-AUG-initiated open reading frame, and three untranslated regions, showing typical features of the family Luteoviridae. Sequence comparison and phylogenetic analyses suggested that WLYaV had the closest relationship with sugarcane yellow leaf virus (ScYLV, but the identities of full genomic nucleotides and deduced amino acid sequence of coat protein (CP were 64.9 and 86.2%, respectively, below the species demarcation thresholds (90% in the family Luteoviridae. Furthermore, agroinoculation of Nicotiana benthamiana leaves with a cDNA clone of WLYaV caused yellowing symptoms on the plant. Our study adds a new polerovirus that is associated with wheat leaf yellowing disease, which would help to identify and control pathogens of wheat.

  12. Control of sweet potato virus diseases.

    Science.gov (United States)

    Loebenstein, Gad

    2015-01-01

    Sweet potato (Ipomoea batatas) is ranked seventh in global food crop production and is the third most important root crop after potato and cassava. Sweet potatoes are vegetative propagated from vines, root slips (sprouts), or tubers. Therefore, virus diseases can be a major constrain, reducing yields markedly, often more than 50%. The main viruses worldwide are Sweet potato feathery mottle virus (SPFMV) and Sweet potato chlorotic stunt virus (SPCSV). Effects on yields by SPFMV or SPCSV alone are minor, or but in complex infection by the two or other viruses yield losses of 50%. The orthodox way of controlling viruses in vegetative propagated crops is by supplying the growers with virus-tested planting material. High-yielding plants are tested for freedom of viruses by PCR, serology, and grafting to sweet potato virus indicator plants. After this, meristem tips are taken from those plants that reacted negative. The meristems were grown into plants which were kept under insect-proof conditions and away from other sweet potato material for distribution to farmers after another cycle of reproduction. © 2015 Elsevier Inc. All rights reserved.

  13. Interspecific hybridization contributes to high genetic diversity and apparent effective population size in an endemic population of mottled ducks (Anas fulvigula maculosa)

    Science.gov (United States)

    Peters, Jeffrey L.; Sonsthagen, Sarah A.; Lavretsky, Philip; Rezsutek, Michael; Johnson, William P.; McCracken, Kevin G.

    2014-01-01

    Under drift-mutation equilibrium, genetic diversity is expected to be correlated with effective population size (Ne). Changes in population size and gene flow are two important processes that can cause populations to deviate from this expected relationship. In this study, we used DNA sequences from six independent loci to examine the influence of these processes on standing genetic diversity in endemic mottled ducks (Anas fulvigula) and geographically widespread mallards (A. platyrhynchos), two species known to hybridize. Mottled ducks have an estimated census size that is about two orders-of-magnitude smaller than that of mallards, yet these two species have similar levels of genetic diversity, especially at nuclear DNA. Coalescent analyses suggest that a population expansion in the mallard at least partly explains this discrepancy, but the mottled duck harbors higher genetic diversity and apparent N e than expected for its census size even after accounting for a population decline. Incorporating gene flow into the model, however, reduced the estimated Ne of mottled ducks to 33 % of the equilibrium Ne and yielded an estimated Ne consistent with census size. We also examined the utility of these loci to distinguish among mallards, mottled ducks, and their hybrids. Most putatively pure individuals were correctly assigned to species, but the power for detecting hybrids was low. Although hybridization with mallards potentially poses a conservation threat to mottled ducks by creating a risk of extinction by hybridization, introgression of mallard alleles has helped maintain high genetic diversity in mottled ducks and might be important for the adaptability and survival of this species.

  14. Structural plasticity of Barley yellow dwarf virus-like cap-independent translation elements in four genera of plant viral RNAs.

    Science.gov (United States)

    Wang, Zhaohui; Kraft, Jelena J; Hui, Alice Y; Miller, W Allen

    2010-06-20

    The 3' untranslated regions (UTRs) of many plant viral RNAs contain cap-independent translation elements (3' CITEs). Among the 3' CITEs, the Barley yellow dwarf virus (BYDV)-like translation elements (BTEs) form a structurally variable and widely distributed group. Viruses in three genera were known to harbor 3' BTEs, defined by the presence of a 17-nt consensus sequence. To understand BTE function, knowledge of phylogenetically conserved structure is essential, yet the secondary structure has been determined only for the BYDV BTE. Here we show that Rose spring dwarf-associated luteovirus, and two viruses in a fourth genus, Umbravirus, contain functional BTEs, despite deviating in the 17nt consensus sequence. Structure probing by selective 2'-hydroxyl acylation and primer extension (SHAPE) revealed conserved and highly variable structures in BTEs in all four genera. We conclude that BTEs tolerate striking evolutionary plasticity in structure, while retaining the ability to stimulate cap-independent translation. Copyright (c) 2010 Elsevier Inc. All rights reserved.

  15. Solution scattering studies on a virus capsid protein as a building block for nanoscale assemblies

    NARCIS (Netherlands)

    Comellas Aragones, M.; Comellas-Aragones, Marta; Sikkema, Friso D.; Delaittre, Guillaume; Terry, Ann E.; King, Stephen M.; Visser, Dirk; Heenan, Richard K.; Nolte, Roeland J.M.; Cornelissen, Jeroen Johannes Lambertus Maria; Feiters, Martin C.

    2011-01-01

    Self-assembled protein cages are versatile building blocks in the construction of biomolecular nanostructures. Because of the defined assembly behaviour the cowpea chlorotic mottle virus (CCMV) protein is often used for such applications. Here we report a detailed solution scattering study of the

  16. Biological and molecular characterization of Brazilian isolates of Zucchini yellow mosaic virus

    Directory of Open Access Journals (Sweden)

    David Marques de Almeida Spadotti

    2015-02-01

    Full Text Available Zucchini yellow mosaic virus (ZYMV causes substantial economic losses in cucurbit crops. Although ZYMV has been present in Brazil for more than 20 years, there is little information about the biological and molecular characteristics of the isolates found in the country. This study aimed to characterize the experimental hosts, pathotypes and genetic diversity of a collection of eleven Brazilian ZYMV isolates within the coat protein gene. For biological analysis, plant species from Amaranthaceae, Chenopodiaceae, Cucurbitaceae, Fabaceae, Solanaceae, and Pedaliaceae were mechanically inoculated and pathotypes were identified based on the reaction of a resistant Cucumis melo, accession PI414723. All of the cucurbit species/varieties and Sesamum indicum were systemically infected with all isolates. The nucleotide sequence variability of the coat protein gene ranged from 82 % to 99 % compared to the corresponding sequences of ZYMV isolates from different geographical locations. No recombination event was detected in the coat protein gene of the isolates.

  17. Expression kinetics of key genes in the early innate immune response to Great Lakes viral hemorrhagic septicemia virus IVb infection in yellow perch (Perca flavescens)

    Science.gov (United States)

    Olson, Wendy; Emmenegger, Eveline; Glenn, Jolene; Simchick, Crystal; Winton, Jim; Goetz, Frederick

    2013-01-01

    The recently discovered strain of viral hemorrhagic septicemia virus, VHSV-IVb, represents an example of the introduction of an extremely pathogenic rhabdovirus capable of infecting a wide variety of new fish species in a new host-environment. The goal of the present study was to delineate the expression kinetics of key genes in the innate immune response relative to the very early stages of VHSV-IVb infection using the yellow perch (Perca flavescens) as a model. Administration of VHSV-IVb by IP-injection into juvenile yellow perch resulted in 84% cumulative mortality, indicating their high susceptibility to this disease. In fish sampled in the very early stages of infection, a significant up-regulation of Mx gene expression in the liver, as well as IL-1β and SAA activation in the head kidney, spleen, and liver was directly correlated to viral load. The potential down-regulation of Mx in the hematopoietic tissues, head kidney and spleen, may represent a strategy utilized by the virus to increase replication.

  18. Identification of a monopartite begomovirus associated with yellow vein mosaic of Mentha longifolia in Saudi Arabia.

    Science.gov (United States)

    Sohrab, Sayed Sartaj; Daur, Ihsanullah

    2018-02-01

    Mentha is a very important crop grown and used extensively for many purposes in the Kingdom of Saudi Arabia. Begomoviruses are whitefly-transmitted viruses causing serious disease in many important plants exhibiting variable symptoms with significant economic loss globally. During farmers' field survey, yellow vein mosaic disease was observed in Mentha longifolia plants growing near tomato fields in Saudi Arabia. The causative agent was identified in 11 out of 19 samples using begomovirus-specific primers and the association of begomovirus with yellow vein mosaic disease in M. longifolia was confirmed. The full-length viral genome and betasatellite were amplified, cloned, and sequenced bidirectionally. The full DNA-A genome was found to have 2785 nucleotides with 1365 bp-associated betasatellite molecule. An attempt was made to amplify DNA-B, but none of the samples produced any positive amplicon of expected size which indicated the presence of monopartite begomovirus. The sequence identity matrix and phylogenetic analysis, based on full genome showed the highest identity (99.6%) with Tomato yellow leaf curl virus (TYLCV) and in phylogenetic analysis it formed a closed cluster with Tomato leaf curl virus infecting tomato and Corchorus crop in Saudi Arabia. The sequence analysis results of betasatellites showed the highest identity (98.9%) with Tomato yellow leaf curl betasatellites infecting tomato and phylogenetic analysis using betasatellites formed a close cluster with Tomato yellow leaf curl betasatellites infecting tomato and Corchorus crops, which has already been reported to cause yellow vein mosaic and leaf curl disease in many cultivated and weed crops growing in Saudi Arabia. The identified begomovirus associated with yellow vein mosaic disease in mentha could be a mutated strain of TYLCV and tentatively designated as TYLCV-Mentha isolate. Based on published data and latest information, this is the first report of identification of Tomato yellow leaf

  19. Kodak film type SO-394-4-1 mottling and hypersensitization test

    Science.gov (United States)

    Weinstein, M. S.

    1972-01-01

    A number of tests were conducted to show the effects of various environmental conditions in terms of mottling and hypersensitization on Kodak Film type SO-394-4-1. The first two weeks of environmental testing is described, along with the test plan and matrix.

  20. Surveillance for yellow Fever virus in non-human primates in southern Brazil, 2001-2011: a tool for prioritizing human populations for vaccination.

    Directory of Open Access Journals (Sweden)

    Marco A B Almeida

    2014-03-01

    Full Text Available In Brazil, epizootics among New World monkey species may indicate circulation of yellow fever (YF virus and provide early warning of risk to humans. Between 1999 and 2001, the southern Brazilian state of Rio Grande do Sul initiated surveillance for epizootics of YF in non-human primates to inform vaccination of human populations. Following a YF outbreak, we analyzed epizootic surveillance data and assessed YF vaccine coverage, timeliness of implementation of vaccination in unvaccinated human populations. From October 2008 through June 2009, circulation of YF virus was confirmed in 67 municipalities in Rio Grande do Sul State; vaccination was recommended in 23 (34% prior to the outbreak and in 16 (24% within two weeks of first epizootic report. In 28 (42% municipalities, vaccination began more than two weeks after first epizootic report. Eleven (52% of 21 laboratory-confirmed human YF cases occurred in two municipalities with delayed vaccination. By 2010, municipalities with confirmed YF epizootics reported higher vaccine coverage than other municipalities that began vaccination. In unvaccinated human populations timely response to epizootic events is critical to prevent human yellow fever cases.

  1. Efeito do Soursop yellow blotch virus no desenvolvimento vegetativo e na produção da gravioleira Effect of the Soursop yellow blotch virus on the growth and yield of soursop diseased plants

    Directory of Open Access Journals (Sweden)

    Antonio A. dos Santos

    2007-03-01

    Full Text Available Os danos causados no desenvolvimento vegetativo e na produção de frutos da gravioleira pelo vírus da mancha-amarela da gravioleira (Soursop yellow blotch virus, SYBV, foram estudados durante os anos de 2000 a 2004 em um experimento com dois tratamentos: plantas sadias e plantas doentes, dispostos em blocos ao acaso, com oito repetições e quatro plantas por parcela. Foram avaliados, anualmente, a altura da planta, diâmetro do caule, número e peso de frutos, sendo que a produção foi monitorada a partir do segundo ano de plantio. As médias relativas à altura de planta, diâmetro do caule, número e peso de frutos das parcelas foram computadas, analisadas estatisticamente e comparadas pelo teste F. As plantas de ambos tratamentos foram originadas de mudas enxertadas, sendo as plantas doentes obtidas por meio de enxertias com propágulos de plantas infectadas com o SYBV. A doença reduziu em 65,11% e 46,72% a altura e o diâmetro do caule, respectivamente, e em 94,7 % e 99,2 % o número e o peso de frutos em relação às plantas sadias.Growth and yield losses on soursop plants due the Soursop yellow blotch virus (SYBV disease were studied during the years 2000 to 2004 in an experiment with two treatments: healthy and SYBV diseased plants. The experiment was disposed in a completely randomized block design with 8 replications with 4 plants per plot. Plant height, trunk diameter, number and weight of fruits were evaluated annually. Data, as plot means, was computed, statistically analyzed and compared by F test. Plants of both treatments were obtained by grafting with buds from healthy and SYBV infected plants. The disease caused percent reductions of 65.11, 46.72, 94.7 and 99.2 in plant height, trunk diameter, in fruit number and fruit weight, respectively.

  2. CD8+ T cells complement antibodies in protecting against yellow fever virus.

    Science.gov (United States)

    Bassi, Maria R; Kongsgaard, Michael; Steffensen, Maria A; Fenger, Christina; Rasmussen, Michael; Skjødt, Karsten; Finsen, Bente; Stryhn, Anette; Buus, Søren; Christensen, Jan P; Thomsen, Allan R

    2015-02-01

    The attenuated yellow fever (YF) vaccine (YF-17D) was developed in the 1930s, yet little is known about the protective mechanisms underlying its efficiency. In this study, we analyzed the relative contribution of cell-mediated and humoral immunity to the vaccine-induced protection in a murine model of YF-17D infection. Using different strains of knockout mice, we found that CD4(+) T cells, B cells, and Abs are required for full clinical protection of vaccinated mice, whereas CD8(+) T cells are dispensable for long-term survival after intracerebral challenge. However, by analyzing the immune response inside the infected CNS, we observed an accelerated T cell influx into the brain after intracerebral challenge of vaccinated mice, and this T cell recruitment correlated with improved virus control in the brain. Using mice deficient in B cells we found that, in the absence of Abs, YF vaccination can still induce some antiviral protection, and in vivo depletion of CD8(+) T cells from these animals revealed a pivotal role for CD8(+) T cells in controlling virus replication in the absence of a humoral response. Finally, we demonstrated that effector CD8(+) T cells also contribute to viral control in the presence of circulating YF-specific Abs. To our knowledge, this is the first time that YF-specific CD8(+) T cells have been demonstrated to possess antiviral activity in vivo. Copyright © 2015 by The American Association of Immunologists, Inc.

  3. Ring structure amino acids affect the suppressor activity of melon aphid-borne yellows virus P0 protein.

    Science.gov (United States)

    Han, Yan-Hong; Xiang, Hai-Ying; Wang, Qian; Li, Yuan-Yuan; Wu, Wen-Qi; Han, Cheng-Gui; Li, Da-Wei; Yu, Jia-Lin

    2010-10-10

    Melon aphid-borne yellows virus (MABYV) is a newly identified polerovirus occurring in China. Here, we demonstrate that the MABYV encoded P0 (P0(MA)) protein is a strong suppressor of post-transcriptional gene silencing (PTGS) with activity comparable to tobacco etch virus (TEV) HC-Pro. In addition we have shown that the LP F-box motif present at the N-terminus of P0(MA) is required for suppressor activity. Detailed mutational analyses on P0(MA) revealed that changing the conserved Trp 212 with non-ring structured amino acids altered silencing suppressor functions. Ala substitutions at positions 12 and 211 for Phe had no effect on P0 suppression-activity, whereas Arg and Glu substitutions had greatly decreased suppressor activity. Furthermore, substitutions targeting Phe at position 30 also resulted in reduced P0 suppression-activity. Altogether, these results suggest that ring structured Trp/Phe residues in P0 have important roles in suppressor activity. Copyright © 2010 Elsevier Inc. All rights reserved.

  4. Breeding biology of Mottled Ducks on agricultural lands in southwestern Louisiana

    Science.gov (United States)

    Durham, R.S.; Afton, A.D.

    2006-01-01

    Breeding biology of Anas fulvigula maculosa (Mottled Ducks) has been described in coastal marsh and associated habitats, but little information is available for agricultural habitats in Louisiana. We located nests to determine nest-initiation dates and clutch sizes during the primary breeding season (February-May) in 1999 (n = 29) and 2000 (n = 37) on agricultural lands in southwestern Louisiana. In 1999, 60% of located nests were initiated between 22 March and 10 April, whereas in 2000, only 22% of nests were initiated during the same time period. Average clutch size was 0.9 eggs smaller in 2000 than in 1999. Annual differences in reproductive parameters corresponded with extremely dry conditions caused by low rainfall before the laying period in 2000. Flooded rice fields appear to be important loafing and feeding habitat of Mottled Ducks nesting in agricultural lands, especially during drought periods when other wetland types are not available or where natural wetlands have been eliminated.

  5. Aceites esenciales de plantas colombianas inactivan el virus del dengue y el virus de la fiebre amarilla Essential oils from Colombian plants inactive dengue virus and yellow fever virus

    Directory of Open Access Journals (Sweden)

    Rocío Meneses

    2009-12-01

    Full Text Available Introducción: Un antiviral contra el virus del dengue (VDEN y el virus de la fiebre amarilla (VFA para tratamiento de los enfermos, no está disponible en el mercado a pesar de numerosas investigaciones con compuestos sintéticos. Objetivo: Evaluar el efecto inhibitorio in vitro sobre el VDEN y el VFA del aceite esencial obtenido de plantas cultivadas en Colombia. Materiales y métodos: Los virus se incubaron con el aceite esencial (100 μg/mL 2 h a 37°C antes de la adsorción a la célula y el efecto inhibitorio fue determinado por el método de reducción de placa. Resultados: El aceite esencial obtenido de 10 y 8 plantas redujo desde 74 hasta 100% placas del VDEN y del VFA, respectivamente. Los aceites de Lippia citriodora (verbena y Pimenta racemosa (laurel fueron más activos contra ambos virus reduciendo 100% las placas. La magnitud del efecto inhibitorio se relacionó con el método de extracción del aceite y la parte de la planta seleccionada. Conclusiones: El aceite esencial de plantas colombianas puede inhibir la replicación in vitro del VDEN y VFA. Se requieren más estudios para determinar la concentración mínima inhibitoria y el índice de selectividad para considerar estas plantas como fuente de compuestos antivirales. Salud UIS 2009; 41: 236-243Introduction: Products obtained from plants can inhibit in vitro viruses that cause human diseases. An antiviral drug against dengue virus (DENV and yellow fever virus (YFV does not exist despite extensive research exploring synthetic compounds. Objective: To evaluate the inhibitory effect on DENV and YFV of essential oils obtained from Colombian plants. Materials and methods: Viruses were incubated with essential oil (100 μg/mL 2 h at 37°C before cell adsorption and the inhibitory effect was determined by plaque reduction assay. Results: The essential oil obtained from 10 and 8 plants reduced from 74 to 100% DENV and YFV plaques, respectively. Essential oils from Lippia citriodora

  6. Identification of Dengue and Chikungunya Cases Among Suspected Cases of Yellow Fever in the Democratic Republic of the Congo.

    Science.gov (United States)

    Makiala-Mandanda, Sheila; Ahuka-Mundeke, Steve; Abbate, Jessica L; Pukuta-Simbu, Elisabeth; Nsio-Mbeta, Justus; Berthet, Nicolas; Leroy, Eric Maurice; Becquart, Pierre; Muyembe-Tamfum, Jean-Jacques

    2018-05-16

    For more than 95% of acute febrile jaundice cases identified through surveillance for yellow fever, a reemerging arthropod-borne viral disease, no etiological exploration is ever done. The aim of this study was to test for other arthropod-borne viruses that can induce the same symptoms in patients enrolled in the yellow fever surveillance in the Democratic Republic of the Congo (DRC). Of 652 patients included in the surveillance of yellow fever in DRC from January 2003 to January 2012, 453 patients that tested negative for yellow fever virus (YFV) immunoglobulin M (IgM) antibodies were selected for the study. Real-time polymerase chain reaction was performed for the detection of dengue, West Nile, Chikungunya, O'nyong-nyong, Rift Valley fever, Zika, and YFV. The average age of patients was 22.1 years. We reported 16 cases (3.5%; confidence interval [CI]: 0.8-5.2) of dengue (serotypes 1 and 2) and 2 cases (0.4%; CI: 0.0-1.0) of Chikungunya. Three patients were co-infected with the two serotypes of dengue virus. Three cases of dengue were found in early July 2010 from the city of Titule (Oriental province) during a laboratory-confirmed outbreak of yellow fever, suggesting simultaneous circulation of dengue and yellow fever viruses. This study showed that dengue and Chikungunya viruses are potential causes of acute febrile jaundice in the DRC and highlights the need to consider dengue and Chikungunya diagnosis in the integrated disease surveillance and response program in the DRC. A prospective study is necessary to establish the epidemiology of these diseases.

  7. Is it time for a new yellow fever vaccine?

    Science.gov (United States)

    Hayes, Edward B

    2010-11-29

    An inexpensive live attenuated vaccine (the 17D vaccine) against yellow fever has been effectively used to prevent yellow fever for more than 70 years. Interest in developing new inactivated vaccines has been spurred by recognition of rare but serious, sometimes fatal adverse events following live virus vaccination. A safer inactivated yellow fever vaccine could be useful for vaccinating people at higher risk of adverse events from the live vaccine, but could also have broader global health utility by lowering the risk-benefit threshold for assuring high levels of yellow fever vaccine coverage. If ongoing trials demonstrate favorable immunogenicity and safety compared to the current vaccine, the practical global health utility of an inactivated vaccine is likely to be determined mostly by cost. Copyright © 2010 Elsevier Ltd. All rights reserved.

  8. Impact of Wolbachia on infection with chikungunya and yellow fever viruses in the mosquito vector Aedes aegypti.

    Directory of Open Access Journals (Sweden)

    Andrew F van den Hurk

    Full Text Available Incidence of disease due to dengue (DENV, chikungunya (CHIKV and yellow fever (YFV viruses is increasing in many parts of the world. The viruses are primarily transmitted by Aedes aegypti, a highly domesticated mosquito species that is notoriously difficult to control. When transinfected into Ae. aegypti, the intracellular bacterium Wolbachia has recently been shown to inhibit replication of DENVs, CHIKV, malaria parasites and filarial nematodes, providing a potentially powerful biocontrol strategy for human pathogens. Because the extent of pathogen reduction can be influenced by the strain of bacterium, we examined whether the wMel strain of Wolbachia influenced CHIKV and YFV infection in Ae. aegypti. Following exposure to viremic blood meals, CHIKV infection and dissemination rates were significantly reduced in mosquitoes with the wMel strain of Wolbachia compared to Wolbachia-uninfected controls. However, similar rates of infection and dissemination were observed in wMel infected and non-infected Ae. aegypti when intrathoracic inoculation was used to deliver virus. YFV infection, dissemination and replication were similar in wMel-infected and control mosquitoes following intrathoracic inoculations. In contrast, mosquitoes with the wMelPop strain of Wolbachia showed at least a 10(4 times reduction in YFV RNA copies compared to controls. The extent of reduction in virus infection depended on Wolbachia strain, titer and strain of the virus, and mode of exposure. Although originally proposed for dengue biocontrol, our results indicate a Wolbachia-based strategy also holds considerable promise for YFV and CHIKV suppression.

  9. Detection and Host Range Study of Virus Associated with Pepper Yellow Leaf Curl Disease

    Directory of Open Access Journals (Sweden)

    SRI SULANDARI

    2006-03-01

    Full Text Available High incidence of Pepper yellow leaf curl virus (PepYLCV was observed in Indonesia since early 2000. Disease incidence in Yogyakarta, Central and West Java reached 100% on Capsicum frutescens, but only 10-35% on C. annuum. As an exception, the disease incidence on C. annuum cv. TM 999 was in the range of 70-100%. The causal agent of the disease, PepYLCV, was detected by polymerase chain reaction. Viral specific DNA fragment of the size ~1600 bp and ~550 bp was amplified from infected plants using two pairs of geminivirus universal primers pAL1v1978/pAL1c715, and pAv494/pAc1048, respectively. The PepYLCV has an intermediate host range including plants belonging to the family of Solanaceae, Leguminosae, and Compositae. The species belonging to the families of Cucurbitaceae, Malvaceae, Chenopodiaceae, and Amaranthaceae were resistant to the virus. Physalis floridana, is very prospective as a propagation host for the geminivirus infecting pepper. Nicotiana spp., cucumber, watermelon, cotton, and Sida sp. could be used as a differential host. Besides, Capsicum frutescens cv. Cakra, tomato, N. benthamiana, N. glutinosa, and Ageratum conyzoides could be used as indicator plants for the geminivirus infecting pepper.

  10. Inheritance of resistance to watermelon mosaic virus in the cucumber line TMG-1: tissue-specific expression and relationship to zucchini yellow mosaic virus resistance.

    Science.gov (United States)

    Wai, T; Grumet, R

    1995-09-01

    The inbred cucumber (Cucumis sativus L.) line TMG-1 is resistant to three potyviruses:zucchini yellow mosaic virus (ZYMV), watermelon mosaic virus (WMV), and the watermelon strain of papaya ringspot virus (PRSV-W). The genetics of resistance to WMV and the relationship of WMV resistance to ZYMV resistance were examined. TMG-1 was crossed with WI-2757, a susceptible inbred line. F1, F2 and backcross progeny populations were screened for resistance to WMV and/or ZYMV. Two independently assorting factors conferred resistance to WMV. One resistance was conferred by a single recessive gene from TMG-1 (wmv-2). The second resistance was conferred by an epistatic interaction between a second recessive gene from TMG-1 (wmv-3) and either a dominant gene from WI-2757 (Wmv-4) or a third recessive gene from TMG-1 (wmv-4) located 20-30 cM from wmv-3. The two resistances exhibited tissue-specific expression. Resistance conferred by wmv-2 was expressed in the cotyledons and throughout the plant. Resistance conferred by wmv-3 + Wmv-4 (or wmv-4) was expressed only in true leaves. The gene conferring resistance to ZYMV appeared to be the same as, or tightly linked to one of the WMV resistance genes, wmv-3.

  11. Complete genome sequence of jacquemontia yellow vein virus, a novel begomovirus infecting Jacquemontia tamnifolia in Venezuela.

    Science.gov (United States)

    Fiallo-Olivé, Elvira; Chirinos, Dorys T; Geraud-Pouey, Francis; Navas-Castillo, Jesús

    2017-08-01

    Wild plants of the family Convolvulaceae are hosts for a few New World begomoviruses (genus Begomovirus, family Geminiviridae). In this work, we report the complete genome sequence of a new begomovirus infecting the wild convolvulaceous plant Jacquemontia tamnifolia in Venezuela. The cloned bipartite genome showed the organization of typical New World begomoviruses and was found to be phylogenetically related to those of begomoviruses from Venezuela and other Caribbean countries. Several recombination events have been shown to have occurred involving genome fragment exchange with related begomoviruses infecting crops such as tomato and cucurbits and wild plants, including Jacquemontia sp. We propose the name jacquemontia yellow vein virus (JacYVV) for this new begomovirus.

  12. Molecular detection and characterisation of Horsegram Yellow ...

    African Journals Online (AJOL)

    specific sets of primers (HYMV-A1500F & HYMV-A1500R and D-HYMV-B2200F & D-HYMV-B2200R) for the amplification of the complete DNA-A and DNA-B components of lima bean isolate of Horsegram yellow mosaic virus (HgYMV-Lb).

  13. The Cucumber vein yellowing virus silencing suppressor P1b can functionally replace HCPro in Plum pox virus infection in a host-specific manner.

    Science.gov (United States)

    Carbonell, Alberto; Dujovny, Gabriela; García, Juan Antonio; Valli, Adrian

    2012-02-01

    Plant viruses of the genera Potyvirus and Ipomovirus (Potyviridae family) use unrelated RNA silencing suppressors (RSS) to counteract antiviral RNA silencing responses. HCPro is the RSS of Potyvirus spp., and its activity is enhanced by the upstream P1 protein. Distinctively, the ipomovirus Cucumber vein yellowing virus (CVYV) lacks HCPro but contains two P1 copies in tandem (P1aP1b), the second of which functions as RSS. Using chimeras based on the potyvirus Plum pox virus (PPV), we found that P1b can functionally replace HCPro in potyviral infections of Nicotiana plants. Interestingly, P1a, the CVYV protein homologous to potyviral P1, disrupted the silencing suppression activity of P1b and reduced the infection efficiency of PPV in Nicotiana benthamiana. Testing the influence of RSS in host specificity, we found that a P1b-expressing chimera poorly infected PPV's natural host, Prunus persica. Conversely, P1b conferred on PPV chimeras the ability to replicate locally in cucumber, CVYV's natural host. The deleterious effect of P1a on PPV infection is host dependent, because the P1aP1b-expressing PPV chimera accumulated in cucumber to higher levels than PPV expressing P1b alone. These results demonstrate that a potyvirus can use different RSS, and that particular RSS and upstream P1-like proteins contribute to defining the virus host range.

  14. Seasonal dynamics of thrips (Thrips tabaci) (Thysanoptera: Thripidae) transmitters of iris yellow spot virus: a serious viral pathogen of onion bulb and seed crops.

    Science.gov (United States)

    Bag, Sudeep; Rondon, Silvia I; Druffel, Keri L; Riley, David G; Pappu, Hanu R

    2014-02-01

    Thrips-transmitted Iris yellow spot virus (IYSV) is an important economic constraint to the production of bulb and seed onion crops in the United States and many other parts of the world. Because the virus is exclusively spread by thrips, the ability to rapidly detect the virus in thrips vectors would facilitate studies on the role of thrips in virus epidemiology, and thus formulation of better vector management strategies. Using a polyclonal antiserum produced against the recombinant, Escherichia coli-expressed nonstructural protein coded by the small (S) RNA of IYSV, an enzyme linked immunosorbent assay was developed for detecting IYSV in individual as well as groups of adult thrips. The approach enabled estimating the proportion of potential thrips transmitters in a large number of field-collected thrips collected from field-grown onion plants. Availability of a practical and inexpensive test to identify viruliferous thrips would be useful in epidemiological studies to better understand the role of thrips vectors in outbreaks of this economically important virus of onion.

  15. Using epidemiological information to develop effective integrated virus disease management strategies.

    Science.gov (United States)

    Jones, Roger A C

    2004-03-01

    Virus diseases cause serious losses in yield and quality of cultivated plants worldwide. These losses and the resulting financial damage can be limited by controlling epidemics using measures that minimise virus infection sources or suppress virus spread. For each combination of virus, cultivated plant and production system, there is an 'economic threshold' above which the financial damage is sufficient to justify using such measures. However, individual measures used alone may bring only small benefits and they may become ineffective, especially over the long term. When diverse control measures that act in different ways are combined and used together, their effects are complementary resulting in far more effective overall control. Such experiences have led to the development of integrated management concepts for virus diseases that combine available host resistance, cultural, chemical and biological control measures. Selecting the ideal mix of measures for each pathosystem and production situation requires detailed knowledge of the epidemiology of the causal virus and the mode of action of each individual control measure so that diverse responses can be devised to meet the unique features of each of the different scenarios considered. The strategies developed must be robust and necessitate minimal extra expense, labour demands and disruption to standard practices. Examples of how epidemiological information can be used to develop effective integrated disease management (IDM) strategies for diverse situations are described. They involve circumstances where virus transmission from plant-to-plant occurs in four different ways: by contact, non-persistently or persistently by insect vectors, and by root-infecting fungi. The examples are: Subterranean clover mottle virus (SCMoV) (contact-transmitted) and Bean yellow mosaic virus (BYMV) (non-persistently aphid-transmitted) in annually self-regenerating clover pasture; three seed-borne viruses (all non-persistently aphid

  16. Effects of Point Mutations in the Major Capsid Protein of Beet Western Yellows Virus on Capsid Formation, Virus Accumulation, and Aphid Transmission

    Science.gov (United States)

    Brault, V.; Bergdoll, M.; Mutterer, J.; Prasad, V.; Pfeffer, S.; Erdinger, M.; Richards, K. E.; Ziegler-Graff, V.

    2003-01-01

    Point mutations were introduced into the major capsid protein (P3) of cloned infectious cDNA of the polerovirus beet western yellows virus (BWYV) by manipulation of cloned infectious cDNA. Seven mutations targeted sites on the S domain predicted to lie on the capsid surface. An eighth mutation eliminated two arginine residues in the R domain, which is thought to extend into the capsid interior. The effects of the mutations on virus capsid formation, virus accumulation in protoplasts and plants, and aphid transmission were tested. All of the mutants replicated in protoplasts. The S-domain mutant W166R failed to protect viral RNA from RNase attack, suggesting that this particular mutation interfered with stable capsid formation. The R-domain mutant R7A/R8A protected ∼90% of the viral RNA strand from RNase, suggesting that lower positive-charge density in the mutant capsid interior interfered with stable packaging of the complete strand into virions. Neither of these mutants systemically infected plants. The six remaining mutants properly packaged viral RNA and could invade Nicotiana clevelandii systemically following agroinfection. Mutant Q121E/N122D was poorly transmitted by aphids, implicating one or both targeted residues in virus-vector interactions. Successful transmission of mutant D172N was accompanied either by reversion to the wild type or by appearance of a second-site mutation, N137D. This finding indicates that D172 is also important for transmission but that the D172N transmission defect can be compensated for by a “reverse” substitution at another site. The results have been used to evaluate possible structural models for the BWYV capsid. PMID:12584348

  17. Incidence of viruses in highbush blueberry (Vaccinium corymbosum L. in Serbia

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    Jevremović Darko

    2016-01-01

    Full Text Available A large-scale survey for highbush blueberry (Vaccinium corymbosum L. viruses in Serbia was performed from 2011 to 2015. A total of 81 leaf samples from 15 locations were collected and analyzed for the presence of 8 viruses. Serological ELISA assay was performed to determine the presence of: Blueberry scorch virus (BlScV, Blueberry shock virus (BlShV, Blueberry shoestring virus (BSSV, Blueberry leaf mottle virus (BLMoV, Tobacco ringspot virus (TRSV and Tomato ringspot virus (ToRSV. All samples were tested for the presence of Blueberry red ringspot virus (BRRV by PCR and for Blueberry mosaic-associated virus (BlMaV by RT-PCR test. The analyses confirmed the presence of BlMaV in 8 (9.9% samples and BRRV in 1 (1.2% sample. No BlScV, BlShV, BLMoV, BSSV, TRSV or ToRSV viruses were detected in any of the analyzed samples.

  18. Genetic diversity and potential vectors and reservoirs of Cucurbit aphid-borne yellows virus in southeastern Spain.

    Science.gov (United States)

    Kassem, Mona A; Juarez, Miguel; Gómez, Pedro; Mengual, Carmen M; Sempere, Raquel N; Plaza, María; Elena, Santiago F; Moreno, Aranzazu; Fereres, Alberto; Aranda, Miguel A

    2013-11-01

    The genetic variability of a Cucurbit aphid-borne yellows virus (CABYV) (genus Polerovirus, family Luteoviridae) population was evaluated by determining the nucleotide sequences of two genomic regions of CABYV isolates collected in open-field melon and squash crops during three consecutive years in Murcia (southeastern Spain). A phylogenetic analysis showed the existence of two major clades. The sequences did not cluster according to host, year, or locality of collection, and nucleotide similarities among isolates were 97 to 100 and 94 to 97% within and between clades, respectively. The ratio of nonsynonymous to synonymous nucleotide substitutions reflected that all open reading frames have been under purifying selection. Estimates of the population's genetic diversity were of the same magnitude as those previously reported for other plant virus populations sampled at larger spatial and temporal scales, suggesting either the presence of CABYV in the surveyed area long before it was first described, multiple introductions, or a particularly rapid diversification. We also determined the full-length sequences of three isolates, identifying the occurrence and location of recombination events along the CABYV genome. Furthermore, our field surveys indicated that Aphis gossypii was the major vector species of CABYV and the most abundant aphid species colonizing melon fields in the Murcia (Spain) region. Our surveys also suggested the importance of the weed species Ecballium elaterium as an alternative host and potential virus reservoir.

  19. Analysis of an RNA-seq Strand-Specific Library from an East Timorese Cucumber Sample Reveals a Complete Cucurbit aphid-borne yellows virus Genome.

    Science.gov (United States)

    Maina, Solomon; Edwards, Owain R; de Almeida, Luis; Ximenes, Abel; Jones, Roger A C

    2017-05-11

    Analysis of an RNA-seq library from cucumber leaf RNA extracted from a fast technology for analysis of nucleic acids (FTA) card revealed the first complete genome of Cucurbit aphid-borne yellows virus (CABYV) from East Timor. We compare it with 35 complete CABYV genomes from other world regions. It most resembled the genome of the South Korean isolate HD118. Copyright © 2017 Maina et al.

  20. Barley yellow dwarf virus in barley crops in Tunisia: prevalence and molecular characterization

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    Asma NAJAR

    2017-05-01

    Full Text Available A field survey was conducted in Tunisia in the North-Eastern regions (Bizerte, CapBon and Zaghouan, the North-Western region (Kef and the Central-Eastern region (Kairouan during the 2011/2012 growing season, in order to determine the incidence and the geographic distribution of Barley yellow dwarf virus (BYDVs in barley fields. Tissue blot immunoassays (TBIA showed that BYDV was most common in Zaghouan (incidence 14%, Cap Bon (14% and Bizerte (35%, in randomly collected samples from these three locations.Among the different BYDVs identified, BYDV-PAV (64% was the most common followed by BYDV-MAV (16% and CYDV-RPV (3%. The coat protein gene sequences of six isolates collected from different regions shared >98% pairwise similarity. In comparisons with other BYDV sequences from around the world, the Tunisian sequences shared greatest homology with isolates 109 and ASL1 from the United States of America and Germany (≈97%, and <90% with all other isolate sequences available in public databases.

  1. Role of Electrostatics in the assembly pathway of a single-stranded RNA virus

    NARCIS (Netherlands)

    Garmann, R.F.; Comas-Garcia, M.; Koay, M.S.T.; Cornelissen, Jeroen Johannes Lambertus Maria; Knobler, C.M.; Gelbart, W.M.

    2014-01-01

    We have recently discovered (R. D. Cadena-Nava et al., J. Virol. 86:3318–3326, 2012, doi:10.1128/JVI.06566-11) that the in vitro packaging of RNA by the capsid protein (CP) of cowpea chlorotic mottle virus is optimal when there is a significant excess of CP, specifically that complete packaging of

  2. RNAi-derived transgenic resistance to Mungbean yellow mosaic India virus in cowpea.

    Science.gov (United States)

    Kumar, Sanjeev; Tanti, Bhaben; Patil, Basavaprabhu L; Mukherjee, Sunil Kumar; Sahoo, Lingaraj

    2017-01-01

    Cowpea is an important grain legume crop of Africa, Latin America, and Southeast Asia. Leaf curl and golden mosaic diseases caused by Mungbean yellow mosaic India virus (MYMIV) have emerged as most devastating viral diseases of cowpea in Southeast Asia. In this study, we employed RNA interference (RNAi) strategy to control cowpea-infecting MYMIV. For this, we generated transgenic cowpea plants harbouring three different intron hairpin RNAi constructs, containing the AC2, AC4 and fusion of AC2 and AC4 (AC2+AC4) of seven cowpea-infecting begomoviruses. The T0 and T1 transgenic cowpea lines of all the three constructs accumulated transgene-specific siRNAs. Transgenic plants were further assayed up to T1 generations, for resistance to MYMIV using agro-infectious clones. Nearly 100% resistance against MYMIV infection was observed in transgenic lines, expressing AC2-hp and AC2+AC4-hp RNA, when compared with untransformed controls and plants transformed with empty vectors, which developed severe viral disease symptoms within 3 weeks. The AC4-hp RNA expressing lines displayed appearance of milder symptoms after 5 weeks of MYMIV-inoculation. Northern blots revealed a positive correlation between the level of transgene-specific siRNAs accumulation and virus resistance. The MYMIV-resistant transgenic lines accumulated nearly zero or very low titres of viral DNA. The transgenic cowpea plants had normal phenotype with no yield penalty in greenhouse conditions. This is the first demonstration of RNAi-derived resistance to MYMIV in cowpea.

  3. Vaccine and Wild-Type Strains of Yellow Fever Virus Engage Distinct Entry Mechanisms and Differentially Stimulate Antiviral Immune Responses.

    Science.gov (United States)

    Fernandez-Garcia, Maria Dolores; Meertens, Laurent; Chazal, Maxime; Hafirassou, Mohamed Lamine; Dejarnac, Ophélie; Zamborlini, Alessia; Despres, Philippe; Sauvonnet, Nathalie; Arenzana-Seisdedos, Fernando; Jouvenet, Nolwenn; Amara, Ali

    2016-02-09

    The live attenuated yellow fever virus (YFV) vaccine 17D stands as a "gold standard" for a successful vaccine. 17D was developed empirically by passaging the wild-type Asibi strain in mouse and chicken embryo tissues. Despite its immense success, the molecular determinants for virulence attenuation and immunogenicity of the 17D vaccine are poorly understood. 17D evolved several mutations in its genome, most of which lie within the envelope (E) protein. Given the major role played by the YFV E protein during virus entry, it has been hypothesized that the residues that diverge between the Asibi and 17D E proteins may be key determinants of attenuation. In this study, we define the process of YFV entry into target cells and investigate its implication in the activation of the antiviral cytokine response. We found that Asibi infects host cells exclusively via the classical clathrin-mediated endocytosis, while 17D exploits a clathrin-independent pathway for infectious entry. We demonstrate that the mutations in the 17D E protein acquired during the attenuation process are sufficient to explain the differential entry of Asibi versus 17D. Interestingly, we show that 17D binds to and infects host cells more efficiently than Asibi, which culminates in increased delivery of viral RNA into the cytosol and robust activation of the cytokine-mediated antiviral response. Overall, our study reveals that 17D vaccine and Asibi enter target cells through distinct mechanisms and highlights a link between 17D attenuation, virus entry, and immune activation. The yellow fever virus (YFV) vaccine 17D is one of the safest and most effective live virus vaccines ever developed. The molecular determinants for virulence attenuation and immunogenicity of 17D are poorly understood. 17D was generated by serially passaging the virulent Asibi strain in vertebrate tissues. Here we examined the entry mechanisms engaged by YFV Asibi and the 17D vaccine. We found the two viruses use different entry

  4. Molecular Evidence for Occurrence of Tomato leaf curl New Delhi virus in Ash Gourd (Benincasa hispida) Germplasm Showing a Severe Yellow Stunt Disease in India.

    Science.gov (United States)

    Roy, Anirban; Spoorthi, P; Panwar, G; Bag, Manas Kumar; Prasad, T V; Kumar, Gunjeet; Gangopadhyay, K K; Dutta, M

    2013-06-01

    An evaluation of 70 accessions of ash gourd germplasm grown at National Bureau of Plant Genetic Resources, New Delhi, India during Kharif season (2010) showed natural occurrence of a yellow stunt disease in three accessions (IC554690, IC036330 and Pusa Ujjwal). A set of begomovirus specific primers used in PCR gave expected amplicon from all the symptomatic plants; however no betasatellite was detected. Complete genome of the begomovirus (DNA-A and DNA-B), amplified through rolling circle amplification, was cloned and sequenced. The begomovirus under study shared high sequence identities to different isolates of Tomato leaf curl New Delhi virus (ToLCNDV) and clustered with them. Among those isolates, the DNA-A and DNA-B of the present begomovirus isolate showed highest 99.6 and 96.8 % sequence identities, respectively with an isolate reported on pumpkin from India (DNA-A: AM286433, DNA-B: AM286435). Based on the sequence analysis, the begomovirus obtained from ash gourd was considered as an isolate of ToLCNDV. Thus, the present findings constitute the first report of occurrence of a new yellow stunt disease in ash gourd from India and demonstrated the association of ToLCNDV with the symptomatic samples. Occurrence of ToLCNDV in ash gourd germplasm not only adds up a new cucurbitaceous host of this virus but also raises the concern about the perpetuation of this virus in absence of its main host tomato and thus has an epidemiological relevance for understanding the rapid spread of this virus in tomato and other hosts in Indian sub-continent.

  5. A mouse model for studying viscerotropic disease caused by yellow fever virus infection.

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    Kathryn C Meier

    2009-10-01

    Full Text Available Mosquito-borne yellow fever virus (YFV causes highly lethal, viscerotropic disease in humans and non-human primates. Despite the availability of efficacious live-attenuated vaccine strains, 17D-204 and 17DD, derived by serial passage of pathogenic YFV strain Asibi, YFV continues to pose a significant threat to human health. Neither the disease caused by wild-type YFV, nor the molecular determinants of vaccine attenuation and immunogenicity, have been well characterized, in large part due to the lack of a small animal model for viscerotropic YFV infection. Here, we describe a small animal model for wild-type YFV that manifests clinical disease representative of that seen in primates without adaptation of the virus to the host, which was required for the current hamster YF model. Investigation of the role of type I interferon (IFN-alpha/beta in protection of mice from viscerotropic YFV infection revealed that mice deficient in the IFN-alpha/beta receptor (A129 or the STAT1 signaling molecule (STAT129 were highly susceptible to infection and disease, succumbing within 6-7 days. Importantly, these animals developed viscerotropic disease reminiscent of human YF, instead of the encephalitic signs typically observed in mice. Rapid viremic dissemination and extensive replication in visceral organs, spleen and liver, was associated with severe pathologies in these tissues and dramatically elevated MCP-1 and IL-6 levels, suggestive of a cytokine storm. In striking contrast, infection of A129 and STAT129 mice with the 17D-204 vaccine virus was subclinical, similar to immunization in humans. Although, like wild-type YFV, 17D-204 virus amplified within regional lymph nodes and seeded a serum viremia in A129 mice, infection of visceral organs was rarely established and rapidly cleared, possibly by type II IFN-dependent mechanisms. The ability to establish systemic infection and cause viscerotropic disease in A129 mice correlated with infectivity for A129

  6. A mouse model for studying viscerotropic disease caused by yellow fever virus infection.

    Science.gov (United States)

    Meier, Kathryn C; Gardner, Christina L; Khoretonenko, Mikhail V; Klimstra, William B; Ryman, Kate D

    2009-10-01

    Mosquito-borne yellow fever virus (YFV) causes highly lethal, viscerotropic disease in humans and non-human primates. Despite the availability of efficacious live-attenuated vaccine strains, 17D-204 and 17DD, derived by serial passage of pathogenic YFV strain Asibi, YFV continues to pose a significant threat to human health. Neither the disease caused by wild-type YFV, nor the molecular determinants of vaccine attenuation and immunogenicity, have been well characterized, in large part due to the lack of a small animal model for viscerotropic YFV infection. Here, we describe a small animal model for wild-type YFV that manifests clinical disease representative of that seen in primates without adaptation of the virus to the host, which was required for the current hamster YF model. Investigation of the role of type I interferon (IFN-alpha/beta) in protection of mice from viscerotropic YFV infection revealed that mice deficient in the IFN-alpha/beta receptor (A129) or the STAT1 signaling molecule (STAT129) were highly susceptible to infection and disease, succumbing within 6-7 days. Importantly, these animals developed viscerotropic disease reminiscent of human YF, instead of the encephalitic signs typically observed in mice. Rapid viremic dissemination and extensive replication in visceral organs, spleen and liver, was associated with severe pathologies in these tissues and dramatically elevated MCP-1 and IL-6 levels, suggestive of a cytokine storm. In striking contrast, infection of A129 and STAT129 mice with the 17D-204 vaccine virus was subclinical, similar to immunization in humans. Although, like wild-type YFV, 17D-204 virus amplified within regional lymph nodes and seeded a serum viremia in A129 mice, infection of visceral organs was rarely established and rapidly cleared, possibly by type II IFN-dependent mechanisms. The ability to establish systemic infection and cause viscerotropic disease in A129 mice correlated with infectivity for A129-derived, but not WT

  7. An inactivated yellow fever 17DD vaccine cultivated in Vero cell cultures.

    Science.gov (United States)

    Pereira, Renata C; Silva, Andrea N M R; Souza, Marta Cristina O; Silva, Marlon V; Neves, Patrícia P C C; Silva, Andrea A M V; Matos, Denise D C S; Herrera, Miguel A O; Yamamura, Anna M Y; Freire, Marcos S; Gaspar, Luciane P; Caride, Elena

    2015-08-20

    Yellow fever is an acute infectious disease caused by prototype virus of the genus Flavivirus. It is endemic in Africa and South America where it represents a serious public health problem causing epidemics of hemorrhagic fever with mortality rates ranging from 20% to 50%. There is no available antiviral therapy and vaccination is the primary method of disease control. Although the attenuated vaccines for yellow fever show safety and efficacy it became necessary to develop a new yellow fever vaccine due to the occurrence of rare serious adverse events, which include visceral and neurotropic diseases. The new inactivated vaccine should be safer and effective as the existing attenuated one. In the present study, the immunogenicity of an inactivated 17DD vaccine in C57BL/6 mice was evaluated. The yellow fever virus was produced by cultivation of Vero cells in bioreactors, inactivated with β-propiolactone, and adsorbed to aluminum hydroxide (alum). Mice were inoculated with inactivated 17DD vaccine containing alum adjuvant and followed by intracerebral challenge with 17DD virus. The results showed that animals receiving 3 doses of the inactivated vaccine (2 μg/dose) with alum adjuvant had neutralizing antibody titers above the cut-off of PRNT50 (Plaque Reduction Neutralization Test). In addition, animals immunized with inactivated vaccine showed survival rate of 100% after the challenge as well as animals immunized with commercial attenuated 17DD vaccine. Copyright © 2015 Elsevier Ltd. All rights reserved.

  8. Genetic structure and evidence of putative Darwinian diversifying selection in the Potato yellow vein virus (PYVV

    Directory of Open Access Journals (Sweden)

    Giovanni Chaves-Bedoya

    2013-08-01

    Full Text Available The population structure and genetic variation of Potato yellow vein virus (PYVV were estimated by analysis of the nucleotide and deduced amino acid sequence of the coat protein of 69 isolates, reported in GenBank, from Solanum tuberosum (ST and Solanum phureja (SP hosts from different regions; predominantly Cundinamarca, Antioquia and Nariño, located in central and southwestern Colombia. Bioinformatics analysis revealed that despite the wide geographic distribution of different hosts and different collecting years, PYVV maintains a genetic similarity between 97.1 to 100.0%, indicating high spatial and temporal genetic stability of the major coat protein. No recombination events were found, but evidence was seen for the first time that this protein could be undergoing Darwinian diversifying selection

  9. Yellow fever

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    Marcelo Nóbrega Litvoc

    Full Text Available Summary The yellow fever (YF virus is a Flavivirus, transmitted by Haemagogus, Sabethes or Aedes aegypti mosquitoes. The disease is endemic in forest areas in Africa and Latin America leading to epizootics in monkeys that constitute the reservoir of the disease. There are two forms of YF: sylvatic, transmitted accidentally when approaching the forests, and urban, which can be perpetuated by Aedes aegypti. In Brazil, the last case of urban YF occurred in 1942. Since then, there has been an expansion of transmission areas from the North and Midwest regions to the South and Southeast. In 2017, the country faced an important outbreak of the disease mainly in the states of Minas Gerais, Espírito Santo and Rio de Janeiro. In 2018, its reach extended from Minas Gerais toward São Paulo. Yellow fever has an incubation period of 3 to 6 days and sudden onset of symptoms with high fever, myalgia, headache, nausea/vomiting and increased transaminases. The disease ranges from asymptomatic to severe forms. The most serious forms occur in around 15% of those infected, with high lethality rates. These forms lead to renal, hepatic and neurological impairment, and bleeding episodes. Treatment of mild and moderate forms is symptomatic, while severe and malignant forms depend on intensive care. Prevention is achieved by administering the vaccine, which is an effective (immunogenicity at 90-98% and safe (0.4 severe events per 100,000 doses measure. In 2018, the first transplants in the world due to YF were performed. There is also an attempt to evaluate the use of active drugs against the virus in order to reduce disease severity.

  10. Molecular and immunological characterization of a DNA-launched yellow fever virus 17D infectious clone.

    Science.gov (United States)

    Jiang, Xiaohong; Dalebout, Tim J; Lukashevich, Igor S; Bredenbeek, Peter J; Franco, David

    2015-04-01

    Yellow fever virus (YFV)-17D is an empirically developed, highly effective live-attenuated vaccine that has been administered to human beings for almost a century. YFV-17D has stood as a paradigm for a successful viral vaccine, and has been exploited as a potential virus vector for the development of recombinant vaccines against other diseases. In this study, a DNA-launched YFV-17D construct (pBeloBAC-FLYF) was explored as a new modality to the standard vaccine to combine the commendable features of both DNA vaccine and live-attenuated viral vaccine. The DNA-launched YFV-17D construct was characterized extensively both in cell culture and in mice. High titres of YFV-17D were generated upon transfection of the DNA into cells, whereas a mutant with deletion in the capsid-coding region (pBeloBAC-YF/ΔC) was restricted to a single round of infection, with no release of progeny virus. Homologous prime-boost immunization of AAD mice with both pBeloBAC-FLYF and pBeloBAC-YF/ΔC elicited specific dose-dependent cellular immune response against YFV-17D. Vaccination of A129 mice with pBeloBAC-FLYF resulted in the induction of YFV-specific neutralizing antibodies in all vaccinated subjects. These promising results underlined the potential of the DNA-launched YFV both as an alternative to standard YFV-17D vaccination and as a vaccine platform for the development of DNA-based recombinant YFV vaccines. © 2015.

  11. Zika virus infection: a public health emergency!

    OpenAIRE

    Qureshi, Muhammad Salman Haider; Qureshi, Bakhtawar Wajeeha; Khan, Ramsha

    2017-01-01

    Zika virus belongs to the family of Flaviviridae. The Flaviviridae family also includes other human pathogens like West Nile virus (WNV), Yellow fever virus (YFV), mosquito transmitted Dengue virus (DENV), Tick borne encephalitic virus (TBEV) and Japanese encephalitis virus (JEV). Zika virus is a mosquito-borne disease and is transmitted by Aedes aegypti mosquito.

  12. Present status of some virus diseases affecting legume crops in Tunisia, and partial characterization of Chickpea chlorotic stunt virus

    Directory of Open Access Journals (Sweden)

    Asma NAJAR

    2011-09-01

    Full Text Available Field surveys were conducted in Tunisia during the 2005‒2006, 2006‒2007 and 2009‒2010 growing seasons to identify viruses which produce yellowing, reddening and/or stunting symptoms of chickpea, faba bean and pea crops. Tissue blot immunoassay (TBIA results showed that Chickpea chlorotic stunt virus (CpCSV was the most common virus, followed by Faba bean necrotic yellows virus, Bean leafroll virus and Beet western yellows virus. The coat protein (CP gene nucleotide sequence of seven CpCSV isolates collected from different regions of Tunisia was compared with sequences of five other isolates in the NCBI database. A homology tree of the CP nucleotide sequences was prepared and CpCSV isolates were grouped into two clusters. The first group contained two Tunisian CpCSV chickpea isolates collected from Bizerte and Kef; sequenced regions showed a high nucleotiode homology (95% to that of the Ethiopian and Sudanese CpCSV isolates. The second group included five Tunisian isolates: two from chickpea, two from pea and one from faba bean, which showed a high homology (96% when compared with the Moroccan, Egyptian and Syrian CpCSV isolates.

  13. What a rheumatologist needs to know about yellow fever vaccine.

    Science.gov (United States)

    Oliveira, Ana Cristina Vanderley; Mota, Licia Maria Henrique da; Santos-Neto, Leopoldo Luiz Dos; Tauil, Pedro Luiz

    2013-04-01

    Patients with rheumatic diseases are more susceptible to infection, due to the underlying disease itself or to its treatment. The rheumatologist should prevent infections in those patients, vaccination being one preventive measure to be adopted. Yellow fever is one of such infectious diseases that can be avoided.The yellow fever vaccine is safe and effective for the general population, but, being an attenuated live virus vaccine, it should be avoided whenever possible in rheumatic patients on immunosuppressive drugs. Considering that yellow fever is endemic in a large area of Brazil, and that vaccination against that disease is indicated for those living in such area or travelling there, rheumatologists need to know that disease, as well as the indications for the yellow fever vaccine and contraindications to it. Our paper was aimed at highlighting the major aspects rheumatologists need to know about the yellow fever vaccine to decide about its indication or contraindication in specific situations. 2013 Elsevier Editora Ltda. All rights reserved.

  14. Inactivation of Dengue and Yellow Fever viruses by heme, cobalt-protoporphyrin IX and tin-protoporphyrin IX.

    Science.gov (United States)

    Assunção-Miranda, I; Cruz-Oliveira, C; Neris, R L S; Figueiredo, C M; Pereira, L P S; Rodrigues, D; Araujo, D F F; Da Poian, A T; Bozza, M T

    2016-03-01

    To investigate the effect of heme, cobalt-protoporphyrin IX and tin-protoporphyrin IX (CoPPIX and SnPPIX), macrocyclic structures composed by a tetrapyrrole ring with a central metallic ion, on Dengue Virus (DENV) and Yellow Fever Virus (YFV) infection. Treatment of HepG2 cells with heme, CoPPIX and SnPPIX after DENV infection reduced infectious particles without affecting viral RNA contents in infected cells. The reduction of viral load occurs only with the direct contact of DENV with porphyrins, suggesting a direct effect on viral particles. Previously incubation of DENV and YFV with heme, CoPPIX and SnPPIX resulted in viral particles inactivation in a dose-dependent manner. Biliverdin, a noncyclical porphyrin, was unable to inactivate the viruses tested. Infection of HepG2 cells with porphyrin-pretreated DENV2 results in a reduced or abolished viral protein synthesis, RNA replication and cell death. Treatment of HepG2 or THP-1 cell lineage with heme or CoPPIX after DENV infection with a very low MOI resulted in a decreased DENV replication and protection from death. Heme, CoPPIX and SnPPIX possess a marked ability to inactivate DENV and YFV, impairing its ability to infect and induce cytopathic effects on target cells. These results open the possibility of therapeutic application of porphyrins or their use as models to design new antiviral drugs against DENV and YFV. © 2016 The Society for Applied Microbiology.

  15. Beet necrotic yellow vein virus accumulates inside resting spores and zoosporangia of its vector Polymyxa betae BNYVV infects P. betae

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    Payton Mark

    2007-04-01

    Full Text Available Abstract Background Plasmodiophorids and chytrids are zoosporic parasites of algae and land plant and are distributed worldwide. There are 35 species belonging to the order Plasmodiophorales and three species, Polymyxa betae, P. graminis, and Spongospora subterranea, are plant viral vectors. Plasmodiophorid transmitted viruses are positive strand RNA viruses belonging to five genera. Beet necrotic yellow vein virus (BNYVV and its vector, P. betae, are the causal agents for rhizomania. Results Evidence of BNYVV replication and movement proteins associating with P. betae resting spores was initially obtained using immunofluorescence labeling and well characterized antisera to each of the BNYVV proteins. Root cross sections were further examined using immunogold labeling and electron microscopy. BNYVV proteins translated from each of the four genomic and subgenomic RNAs accumulate inside P. betae resting spores and zoospores. Statistical analysis was used to determine if immunolabelling detected viral proteins in specific subcellular domains and at a level greater than in control samples. Conclusion Virus-like particles were detected in zoosporangia. Association of BNYVV replication and movement proteins with sporangial and sporogenic stages of P. betae suggest that BNYVV resides inside its vector during more than one life cycle stage. These data suggest that P. betae might be a host as well as a vector for BNYVV

  16. Beet necrotic yellow vein virus accumulates inside resting spores and zoosporangia of its vector Polymyxa betae BNYVV infects P. betae.

    Science.gov (United States)

    Lubicz, Jeanmarie Verchot; Rush, Charles M; Payton, Mark; Colberg, Terry

    2007-04-05

    Plasmodiophorids and chytrids are zoosporic parasites of algae and land plant and are distributed worldwide. There are 35 species belonging to the order Plasmodiophorales and three species, Polymyxa betae, P. graminis, and Spongospora subterranea, are plant viral vectors. Plasmodiophorid transmitted viruses are positive strand RNA viruses belonging to five genera. Beet necrotic yellow vein virus (BNYVV) and its vector, P. betae, are the causal agents for rhizomania. Evidence of BNYVV replication and movement proteins associating with P. betae resting spores was initially obtained using immunofluorescence labeling and well characterized antisera to each of the BNYVV proteins. Root cross sections were further examined using immunogold labeling and electron microscopy. BNYVV proteins translated from each of the four genomic and subgenomic RNAs accumulate inside P. betae resting spores and zoospores. Statistical analysis was used to determine if immunolabelling detected viral proteins in specific subcellular domains and at a level greater than in control samples. Virus-like particles were detected in zoosporangia. Association of BNYVV replication and movement proteins with sporangial and sporogenic stages of P. betae suggest that BNYVV resides inside its vector during more than one life cycle stage. These data suggest that P. betae might be a host as well as a vector for BNYVV.

  17. Febre amarela Yellow fever

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    Pedro Fernando da Costa Vasconcelos

    2003-04-01

    Full Text Available A febre amarela é doenca infecciosa não-contagiosa causada por um arbovírus mantido em ciclos silvestres em que macacos atuam como hospedeiros amplificadores e mosquitos dos gêneros Aedes na África, e Haemagogus e Sabethes na América, são os transmissores. Cerca de 90% dos casos da doença apresentam-se com formas clínicas benignas que evoluem para a cura, enquanto 10% desenvolvem quadros dramáticos com mortalidade em torno de 50%. O problema mostra-se mais grave em África onde ainda há casos urbanos. Nas Américas, no período de 1970-2001, descreveram-se 4.543 casos. Os países que mais diagnosticaram a doença foram o Peru (51,5%, a Bolívia (20,1% e o Brasil (18,7%. Os métodos diagnósticos utilizados incluem a sorologia (IgM, isolamento viral, imunohistoquímica e RT-PCR. A zoonose não pode ser erradicada, mas, a doença humana é prevenível mediante a vacinação com a amostra 17D do vírus amarílico. A OMS recomenda nova vacinação a cada 10 anos. Neste artigo são revistos os principais conceitos da doença e os casos de mortes associados à vacina.Yellow fever is an infectious and non-contagious disease caused by an arbovirus, the yellow fever virus. The agent is maintained in jungle cycles among primates as vertebrate hosts and mosquitoes, especially Aedes in Africa, and Haemagogus and Sabethes in America. Approximately 90% of the infections are mild or asymptomatic, while 10% course to a severe clinical picture with 50% case-fatality rate. Yellow fever is largely distributed in Africa where urban epidemics are still reported. In South America, between 1970-2001, 4,543 cases were reported, mostly from Peru (51.5%, Bolivia (20.1% and Brazil (18.7%. The disease is diagnosed by serology (detection of IgM, virus isolation, immunohistochemistry and RT-PCR. Yellow fever is a zoonosis and cannot be eradicated, but it is preventable in man by using the 17D vaccine. A single dose is enough to protect an individual for at least

  18. Identification of insecticidal principals from cucumber seed oil against the yellow fever mosquito, Aedes aegypti

    Science.gov (United States)

    The yellow fever mosquito, Aedes aegypti, is one of the most medically important mosquito species due to its ability to spread viruses of yellow fever, dengue fever and Zika in humans. In this study, the insecticidal activity of seventeen plant essential oils were evaluated to toxicity by topical a...

  19. Mapping the nuclear localization signal in the matrix protein of potato yellow dwarf virus.

    Science.gov (United States)

    Anderson, Gavin; Jang, Chanyong; Wang, Renyuan; Goodin, Michael

    2018-05-01

    The ability of the matrix (M) protein of potato yellow dwarf virus (PYDV) to remodel nuclear membranes is controlled by a di-leucine motif located at residues 223 and 224 of its primary structure. This function can be uncoupled from that of its nuclear localization signal (NLS), which is controlled primarily by lysine and arginine residues immediately downstream of the LL motif. In planta localization of green fluorescent protein fusions, bimolecular fluorescence complementation assays with nuclear import receptor importin-α1 and yeast-based nuclear import assays provided three independent experimental approaches to validate the authenticity of the M-NLS. The carboxy terminus of M is predicted to contain a nuclear export signal, which is belived to be functional, given the ability of M to bind the Arabidopsis nuclear export receptor 1 (XPO1). The nuclear shuttle activity of M has implications for the cell-to-cell movement of PYDV nucleocapsids, based upon its interaction with the N and Y proteins.

  20. Durable field resistance to wheat yellow mosaic virus in transgenic wheat containing the antisense virus polymerase gene.

    Science.gov (United States)

    Chen, Ming; Sun, Liying; Wu, Hongya; Chen, Jiong; Ma, Youzhi; Zhang, Xiaoxiang; Du, Lipu; Cheng, Shunhe; Zhang, Boqiao; Ye, Xingguo; Pang, Junlan; Zhang, Xinmei; Li, Liancheng; Andika, Ida B; Chen, Jianping; Xu, Huijun

    2014-05-01

    Wheat yellow mosaic virus (WYMV) has spread rapidly and causes serious yield losses in the major wheat-growing areas in China. Because it is vectored by the fungus-like organism Polymyxa graminis that survives for long periods in soil, it is difficult to eliminate by conventional crop management or fungicides. There is also only limited resistance in commercial cultivars. In this research, fourteen independent transgenic events were obtained by co-transformation with the antisense NIb8 gene (the NIb replicase of WYMV) and a selectable gene bar. Four original transgenic lines (N12, N13, N14 and N15) and an offspring line (N12-1) showed high and durable resistance to WYMV in the field. Four resistant lines were shown to have segregated and only contain NIb8 (without bar) by PCR and herbicide resistance testing in the later generations. Line N12-1 showed broad-spectrum resistance to WYMV isolates from different sites in China. After growing in the infested soil, WYMV could not be detected by tissue printing and Western blot assays of transgenic wheat. The grain yield of transgenic wheat was about 10% greater than the wild-type susceptible control. Northern blot and small RNA deep sequencing analyses showed that there was no accumulation of small interfering RNAs targeting the NIb8 gene in transgenic wheat plants, suggesting that transgene RNA silencing, a common mechanism of virus-derived disease resistance, is not involved in the process of WYMV resistance. This durable and broad-spectrum resistance to WYMV in transgenic wheat will be useful for alleviating the damage caused by WYMV. © 2013 Society for Experimental Biology, Association of Applied Biologists and John Wiley & Sons Ltd.

  1. Nest-site selection and success of mottled ducks on agricultural lands in southwest Louisiana

    Science.gov (United States)

    Durham, R.S.; Afton, A.D.

    2003-01-01

    Listing of the mottled duck (Anas fulvigula maculosa) as a priority species in the Gulf Coast Joint Venture of the North American Waterfowl Management Plan, coupled with recent declines of rice (Oryza sativa) acreage, led us to investigate the nesting ecology of this species on agricultural lands in southwest Louisiana. We examined nest-site selection at macro- and microhabitat levels, nest success, causes of nest failures, and habitat features influencing nest success. We found that female mottled ducks preferred to nest in permanent pastures with knolls (53% of nests) and idle fields (22% of nests). Vegetation height was greater at nests than at random points within the same macrohabitat patch. Successful nests were associated with greater numbers of plant species, located farther from water, and associated with higher vegetation density values than were unsuccessful nests. We determined that mammalian predators caused most nest failures (77% of 52 unsuccessful nests). Our results suggest that nest success of mottled ducks on agricultural lands in southwest Louisiana could be improved by 1) locating large permanent pastures and idle fields near rice fields and other available wetlands, 2) managing plant communities in these upland areas to favor dense stands of perennial bunch grasses, tall composites, dewberry (Rubus trivialis), and other native grasses and forbs, and 3) managing cattle-stocking rates and the duration and timing of grazing to promote tall, dense stands of these plant taxa during the nesting season (March-June).

  2. Lymphocyte subset analyses in healthy adults vaccinated with yellow fever 17DD virus

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    Ana Paula dos Santos

    2005-05-01

    Full Text Available In this study the kinetics of humoral and cellular immune responses in first-time vaccinees and re-vaccinees with the yellow fever 17DD vaccine virus was analyzed. Flow cytometric analyses were used to determine percentual values of T and B cells in parallel to the yellow fever neutralizing antibody production. All lymphocyte subsets analyzed were augmented around the 30th post vaccination day, both for first-time vaccinees and re-vaccinees. CD3+ T cells increased from 30.8% (SE ± 4% to 61.15% (SE ± 4.2%, CD4+ T cells from 22.4% (SE ± 3.6% to 39.17% (SE ± 2% with 43% of these cells corresponding to CD4+CD45RO+ T cells, CD8+ T cells from 15.2% (SE ± 2.9% to 27% (SE ± 3% with 70% corresponding to CD8+CD45RO+ T cells in first-time vaccinees. In re-vaccinees, the CD3+ T cells increased from 50.7% (SE ± 3% to 80% (SE ± 2.3%, CD4+ T cells from 24.9% (SE ± 1.4% to 40% (SE ± 3% presenting a percentage of 95% CD4+CD45RO+ T cells, CD8+ T cells from 19.7% (SE ± 1.8% to 25% (SE ± 2%. Among CD8+CD38+ T cells there could be observed an increase from 15 to 41.6% in first-time vaccinees and 20.7 to 62.6% in re-vaccinees. Regarding neutralizing antibodies, the re-vaccinees presented high titers even before re-vaccination. The levels of neutralizing antibodies of first-time vaccinees were similar to those presented by re-vaccinees at day 30 after vaccination, indicating the success of primary vaccination. Our data provide a basis for further studies on immunological behavior of the YF 17DD vaccine.

  3. Expression of tomato yellow leaf curl virus coat protein using baculovirus expression system and evaluation of its utility as a viral antigen.

    Science.gov (United States)

    Elgaied, Lamiaa; Salem, Reda; Elmenofy, Wael

    2017-08-01

    DNA encoding the coat protein (CP) of an Egyptian isolate of tomato yellow leaf curl virus (TYLCV) was inserted into the genome of Autographa californica nucleopolyhedrovirus (AcNPV) under the control of polyhedrin promoter. The generated recombinant baculovirus construct harboring the coat protein gene was characterized using PCR analysis. The recombinant coat protein expressed in infected insect cells was used as a coating antigen in an indirect Enzyme-linked immunosorbent assay (ELISA) and dot blot to test its utility for the detection of antibody generated against TYLCV virus particles. The results of ELISA and dot blot showed that the TYLCV-antibodies reacted positively with extracts of infected cells using the recombinant virus as a coating antigen with strong signals as well as the TYLCV infected tomato and beat plant extracts as positive samples. Scanning electron microscope examination showed that the expressed TYLCV coat protein was self-assembled into virus-like particles (VLPs) similar in size and morphology to TYLCV virus particles. These results concluded that, the expressed coat protein of TYLCV using baculovirus vector system is a reliable candidate for generation of anti-CP antibody for inexpensive detection of TYLCV-infected plants using indirect CP-ELISA or dot blot with high specificity.

  4. Serious adverse events associated with yellow fever vaccine.

    Science.gov (United States)

    de Menezes Martins, Reinaldo; Fernandes Leal, Maria da Luz; Homma, Akira

    2015-01-01

    Yellow fever vaccine was considered one of the safest vaccines, but in recent years it was found that it could rarely cause invasive and disseminated disease in some otherwise healthy individuals, with high lethality. After extensive studies, although some risk factors have been identified, the real cause of causes of this serious adverse event are largely unknown, but findings point to individual host factors. Meningoencephalitis, once considered to happen only in children less than 6 months of age, has also been identified in older children and adults, but with good prognosis. Efforts are being made to develop a safer yellow fever vaccine, and an inactivated vaccine or a vaccine prepared with the vaccine virus envelope produced in plants are being tested. Even with serious and rare adverse events, yellow fever vaccine is the best way to avoid yellow fever, a disease of high lethality and should be used routinely in endemic areas, and on people from non-endemic areas that could be exposed, according to a careful risk-benefit analysis.

  5. Multiplex detection of plant pathogens using a microsphere immunoassay technology.

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    Ratthaphol Charlermroj

    Full Text Available Plant pathogens are a serious problem for seed export, plant disease control and plant quarantine. Rapid and accurate screening tests are urgently required to protect and prevent plant diseases spreading worldwide. A novel multiplex detection method was developed based on microsphere immunoassays to simultaneously detect four important plant pathogens: a fruit blotch bacterium Acidovorax avenae subsp. citrulli (Aac, chilli vein-banding mottle virus (CVbMV, potyvirus, watermelon silver mottle virus (WSMoV, tospovirus serogroup IV and melon yellow spot virus (MYSV, tospovirus. An antibody for each plant pathogen was linked on a fluorescence-coded magnetic microsphere set which was used to capture corresponding pathogen. The presence of pathogens was detected by R-phycoerythrin (RPE-labeled antibodies specific to the pathogens. The assay conditions were optimized by identifying appropriate antibody pairs, blocking buffer, concentration of RPE-labeled antibodies and assay time. Once conditions were optimized, the assay was able to detect all four plant pathogens precisely and accurately with substantially higher sensitivity than enzyme-linked immunosorbent assay (ELISA when spiked in buffer and in healthy watermelon leaf extract. The assay time of the microsphere immunoassay (1 hour was much shorter than that of ELISA (4 hours. This system was also shown to be capable of detecting the pathogens in naturally infected plant samples and is a major advancement in plant pathogen detection.

  6. Multiplex detection of plant pathogens using a microsphere immunoassay technology.

    Science.gov (United States)

    Charlermroj, Ratthaphol; Himananto, Orawan; Seepiban, Channarong; Kumpoosiri, Mallika; Warin, Nuchnard; Oplatowska, Michalina; Gajanandana, Oraprapai; Grant, Irene R; Karoonuthaisiri, Nitsara; Elliott, Christopher T

    2013-01-01

    Plant pathogens are a serious problem for seed export, plant disease control and plant quarantine. Rapid and accurate screening tests are urgently required to protect and prevent plant diseases spreading worldwide. A novel multiplex detection method was developed based on microsphere immunoassays to simultaneously detect four important plant pathogens: a fruit blotch bacterium Acidovorax avenae subsp. citrulli (Aac), chilli vein-banding mottle virus (CVbMV, potyvirus), watermelon silver mottle virus (WSMoV, tospovirus serogroup IV) and melon yellow spot virus (MYSV, tospovirus). An antibody for each plant pathogen was linked on a fluorescence-coded magnetic microsphere set which was used to capture corresponding pathogen. The presence of pathogens was detected by R-phycoerythrin (RPE)-labeled antibodies specific to the pathogens. The assay conditions were optimized by identifying appropriate antibody pairs, blocking buffer, concentration of RPE-labeled antibodies and assay time. Once conditions were optimized, the assay was able to detect all four plant pathogens precisely and accurately with substantially higher sensitivity than enzyme-linked immunosorbent assay (ELISA) when spiked in buffer and in healthy watermelon leaf extract. The assay time of the microsphere immunoassay (1 hour) was much shorter than that of ELISA (4 hours). This system was also shown to be capable of detecting the pathogens in naturally infected plant samples and is a major advancement in plant pathogen detection.

  7. Comparative Analyses of Tomato yellow leaf curl virus C4 Protein-Interacting Host Proteins in Healthy and Infected Tomato Tissues

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    Namgyu Kim

    2016-10-01

    Full Text Available Tomato yellow leaf curl virus (TYLCV, a member of the genus Begomovirus, is one of the most important viruses of cultivated tomatoes worldwide, mainly causing yellowing and curling of leaves with stunting in plants. TYLCV causes severe problems in sub-tropical and tropical countries, as well as in Korea. However, the mechanism of TYLCV infection remains unclear, although the function of each viral component has been identified. TYLCV C4 codes for a small protein involved in various cellular functions, including symptom determination, gene silencing, viral movement, and induction of the plant defense response. In this study, through yeast-two hybrid screenings, we identified TYLCV C4-interacting host proteins from both healthy and symptom-exhibiting tomato tissues, to determine the role of TYLCV C4 proteins in the infection processes. Comparative analyses of 28 proteins from healthy tissues and 36 from infected tissues showing interactions with TYLCV C4 indicated that TYLCV C4 mainly interacts with host proteins involved in translation, ubiquitination, and plant defense, and most interacting proteins differed between the two tissues but belong to similar molecular functional categories. Four proteins—two ribosomal proteins, S-adenosyl-L-homocysteine hydrolase, and 14-3-3 family protein—were detected in both tissues. Furthermore, the identified proteins in symptom-exhibiting tissues showed greater involvement in plant defenses. Some are key regulators, such as receptor-like kinases and pathogenesis-related proteins, of plant defenses. Thus, TYLCV C4 may contribute to the suppression of host defense during TYLCV infection and be involved in ubiquitination for viral infection.

  8. The complete nucleotide sequence of the barley yellow dwarf GPV isolate from China shows that it is a new member of the genus Polerovirus.

    Science.gov (United States)

    Zhang, Wenwei; Cheng, Zhuomin; Xu, Lei; Wu, Maosen; Waterhouse, Peter; Zhou, Guanghe; Li, Shifang

    2009-01-01

    The complete nucleotide sequence of the ssRNA genome of a Chinese GPV isolate of barley yellow dwarf virus (BYDV) was determined. It comprised 5673 nucleotides, and the deduced genome organization resembled that of members of the genus Polerovirus. It was most closely related to cereal yellow dwarf virus-RPV (77% nt identity over the entire genome; coat protein amino acid identity 79%). The GPV isolate also differs in vector specificity from other BYDV strains. Biological properties, phylogenetic analyses and detailed sequence comparisons suggest that GPV should be considered a member of a new species within the genus, and the name Wheat yellow dwarf virus-GPV is proposed.

  9. Duckling survival, fecundity, and habitat selection of mottled duck broods on the upper Texas Gulf Coast

    Science.gov (United States)

    Rigby, Elizabeth A.; Haukos, David A.

    2015-01-01

    Mottled ducks (Anas fulvigula) on the western Gulf Coast have exhibited a steep population decline since the mid 1990s. Low rates of breeding incidence and nest success have been implicated in this decline, but duckling survival and the habitat needs of broods have not been previously investigated in this region. We fitted mottled duck ducklings and adult females with radio transmitters and tracked broods to estimate duckling survival and brood habitat selection on the upper Texas Gulf Coast. Duckling survival to 30 days was high (range among models 0.354–0.567) compared to other dabbling duck species. Estimated fecundity was low, (range among models 0.398–0.634) however, indicating that overall reproductive output is low. Within coastal marsh, broods selected home ranges with more water cover and less upland and fresh marsh landcover than was available in the study area. Within coastal marsh home ranges, broods selected for water cover relative to other landcover types, and there was some evidence that broods avoided unvegetated landcover. Although high quality brood habitat is undeniably important, management efforts to increase mottled duck population growth on the western Gulf Coast may best be spent on increasing nesting habitat quality to increase nest success and breeding incidence.

  10. Métodos usados en Colombia para el estudio del virus de la fiebre amarilla

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    Manuel Roca García

    1946-07-01

    Full Text Available The object of this article is to describe techniques used for the study and maintenance of the virus of yellow fever in the laboratory at Villavicencio, Colombia. The characteristics of ye- Howfever virus are briefly described. The susceptibility of white mice of the "Swiss" strain is discussed, and the technique of their routine use for tests of the presence of virus described. The methods of virus titration, specificity tests and protection tests are explained in some detail. The susceptibility of Colombian monkeys to yellow fever virus and their use as laboratory animals in virus studies are described. The isolation of yellow fever virus from suspected cases of human infection is discussed and the technique of preserving virus by desiccation described. Methods of handling mosquitoes in the laboratory are described, with special reference to techniques adapted to transmission studies with Haemagogus mosquitoes.

  11. Oligonucleotide Length-Dependent Formation of Virus-Like Particles.

    Science.gov (United States)

    Maassen, Stan J; de Ruiter, Mark V; Lindhoud, Saskia; Cornelissen, Jeroen J L M

    2018-05-23

    Understanding the assembly pathway of viruses can contribute to creating monodisperse virus-based materials. In this study, the cowpea chlorotic mottle virus (CCMV) is used to determine the interactions between the capsid proteins of viruses and their cargo. The assembly of the capsid proteins in the presence of different lengths of short, single-stranded (ss) DNA is studied at neutral pH, at which the protein-protein interactions are weak. Chromatography, electrophoresis, microscopy, and light scattering data show that the assembly efficiency and speed of the particles increase with increasing length of oligonucleotides. The minimal length required for assembly under the conditions used herein is 14 nucleotides. Assembly of particles containing such short strands of ssDNA can take almost a month. This slow assembly process enabled the study of intermediate states, which confirmed a low cooperative assembly for CCMV and allowed for further expansion of current assembly theories. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Intrathecal antibody production in two cases of yellow fever vaccine associated neurotropic disease in Argentina.

    Science.gov (United States)

    Pires-Marczeski, Fanny Clara; Martinez, Valeria Paula; Nemirovsky, Corina; Padula, Paula Julieta

    2011-12-01

    During the period 2007-2008 several epizootics of Yellow fever with dead of monkeys occurred in southeastern Brasil, Paraguay, and northeastern Argentina. In 2008 after a Yellow fever outbreak an exhaustive prevention campaign took place in Argentina using 17D live attenuated Yellow fever vaccine. This vaccine is considered one of the safest live virus vaccines, although serious adverse reactions may occur after vaccination, and vaccine-associated neurotropic disease are reported rarely. The aim of this study was to confirm two serious adverse events associated to Yellow fever vaccine in Argentina, and to describe the analysis performed to assess the origin of specific IgM against Yellow fever virus (YFV) in cerebrospinal fluid (CSF). Both cases coincided with the Yellow fever vaccine-associated neurotropic disease case definition, being clinical diagnosis longitudinal myelitis (case 1) and meningoencephalitis (case 2). Specific YFV antibodies were detected in CSF and serum samples in both cases by IgM antibody-capture ELISA. No other cause of neurological disease was identified. In order to obtain a conclusive diagnosis of central nervous system (CNS) infection the IgM antibody index (AI(IgM) ) was calculated. High AI(IgM) values were found in both cases indicating intrathecal production of antibodies and, therefore, CNS post-vaccinal YFV infection could be definitively associated to YFV vaccination. Copyright © 2011 Wiley Periodicals, Inc.

  13. Homologous genetic recombination in the yellow head complex of nidoviruses infecting Penaeus monodon shrimp.

    Science.gov (United States)

    Wijegoonawardane, Priyanjalie K M; Sittidilokratna, Nusra; Petchampai, Natthida; Cowley, Jeff A; Gudkovs, Nicholas; Walker, Peter J

    2009-07-20

    Yellow head virus (YHV) is a highly virulent pathogen of Penaeus monodon shrimp. It is one of six known genotypes in the yellow head complex of nidoviruses which also includes mildly pathogenic gill-associated virus (GAV, genotype 2) and four other genotypes (genotypes 3-6) that have been detected only in healthy shrimp. In this study, comparative phylogenetic analyses conducted on replicase- (ORF1b) and glycoprotein- (ORF3) gene amplicons identified 10 putative natural recombinants amongst 28 viruses representing all six genotypes from across the Indo-Pacific region. The approximately 4.6 kb genomic region spanning the two amplicons was sequenced for three putative recombinant viruses from Vietnam (genotype 3/5), the Philippines (genotype 5/2) and Indonesia (genotype 3/2). SimPlot analysis using these and representative parental virus sequences confirmed that each was a recombinant genotype and identified a recombination hotspot in a region just upstream of the ORF1b C-terminus. Maximum-likelihood breakpoint analysis predicted identical crossover positions in the Vietnamese and Indonesian recombinants, and a crossover position 12 nt upstream in the Philippine recombinant. Homologous genetic recombination in the same genome region was also demonstrated in recombinants generated experimentally in shrimp co-infected with YHV and GAV. The high frequency with which natural recombinants were identified indicates that genetic exchange amongst genotypes is occurring commonly in Asia and playing a significant role in expanding the genetic diversity in the yellow head complex. This is the first evidence of genetic recombination in viruses infecting crustaceans and has significant implications for the pathogenesis of infection and diagnosis of these newly emerging invertebrate pathogens.

  14. Phylodynamics of Yellow Fever Virus in the Americas: new insights into the origin of the 2017 Brazilian outbreak.

    Science.gov (United States)

    Mir, Daiana; Delatorre, Edson; Bonaldo, Myrna; Lourenço-de-Oliveira, Ricardo; Vicente, Ana Carolina; Bello, Gonzalo

    2017-08-07

    Yellow fever virus (YFV) strains circulating in the Americas belong to two distinct genotypes (I and II) that have diversified into several concurrent enzootic lineages. Since 1999, YFV genotype I has spread outside endemic regions and its recent (2017) reemergence in non-endemic Southeastern Brazilian states fuels one of the largest epizootic of jungle Yellow Fever registered in the country. To better understand this phenomenon, we reconstructed the phylodynamics of YFV American genotypes using sequences from nine countries sampled along 60 years, including strains from Brazilian 2017 outbreak. Our analyses reveals that YFV genotypes I and II follow roughly similar evolutionary and demographic dynamics until the early 1990s, when a dramatic change in the diversification process of the genotype I occurred associated with the emergence and dissemination of a new lineage (here called modern). Trinidad and Tobago was the most likely source of the YFV modern-lineage that spread to Brazil and Venezuela around the late 1980s, where it replaced all lineages previously circulating. The modern-lineage caused all major YFV outbreaks detected in non-endemic South American regions since 2000, including the 2017 Brazilian outbreak, and its dissemination was coupled to the accumulation of several amino acid substitutions particularly within non-structural viral proteins.

  15. Investigation of a possible yellow fever epidemic and serosurvey for flavivirus infections in northern Cameroon, 1984

    OpenAIRE

    Tsai, T. F.; Lazuick, J. S.; Ngah, R. W.; Mafiamba, P. C.; Quincke, G.; Monath, T. P.

    1987-01-01

    A cluster of fatal hepatitis cases in northern Cameroon in 1984 stimulated a field investigation to rule out an epidemic of yellow fever. A serosurvey of villages in the extreme north of the country, in a Sudan savanna (SS) phytogeographical zone, disclosed no evidence of recent yellow fever infection. However, further south, in a Guinea savanna (GS) phytogeographical zone, serological evidence was found of endemic yellow fever virus transmission. The results indicate a potential for epidemic...

  16. Dengue-2 and yellow fever 17DD viruses infect human dendritic cells, resulting in an induction of activation markers, cytokines and chemokines and secretion of different TNF-α and IFN-α profiles

    Directory of Open Access Journals (Sweden)

    Mariana Gandini

    2011-08-01

    Full Text Available Flaviviruses cause severe acute febrile and haemorrhagic infections, including dengue and yellow fever and the pathogenesis of these infections is caused by an exacerbated immune response. Dendritic cells (DCs are targets for dengue virus (DENV and yellow fever virus (YF replication and are the first cell population to interact with these viruses during a natural infection, which leads to an induction of protective immunity in humans. We studied the infectivity of DENV2 (strain 16681, a YF vaccine (YF17DD and a chimeric YF17D/DENV2 vaccine in monocyte-derived DCs in vitro with regard to cell maturation, activation and cytokine production. Higher viral antigen positive cell frequencies were observed for DENV2 when compared with both vaccine viruses. Flavivirus-infected cultures exhibited dendritic cell activation and maturation molecules. CD38 expression on DCs was enhanced for both DENV2 and YF17DD, whereas OX40L expression was decreased as compared to mock-stimulated cells, suggesting that a T helper 1 profile is favoured. Tumor necrosis factor (TNF-α production in cell cultures was significantly higher in DENV2-infected cultures than in cultures infected with YF17DD or YF17D/DENV. In contrast, the vaccines induced higher IFN-α levels than DENV2. The differential cytokine production indicates that DENV2 results in TNF induction, which discriminates it from vaccine viruses that preferentially stimulate interferon expression. These differential response profiles may influence the pathogenic infection outcome.

  17. Animal models of yellow fever and their application in clinical research.

    Science.gov (United States)

    Julander, Justin G

    2016-06-01

    Yellow fever virus (YFV) is an arbovirus that causes significant human morbidity and mortality. This virus has been studied intensively over the past century, although there are still no treatment options for those who become infected. Periodic and unpredictable yellow fever (YF) outbreaks in Africa and South America continue to occur and underscore the ongoing need to further understand this viral disease and to develop additional countermeasures to prevent or treat cases of illness. The use of animal models of YF is critical to accomplishing this goal. There are several animal models of YF that replicate various aspects of clinical disease and have provided insight into pathogenic mechanisms of the virus. These typically include mice, hamsters and non-human primates (NHP). The utilities and shortcomings of the available animal models of YF are discussed. Information on recent discoveries that have been made in the field of YFV research is also included as well as important future directions in further ameliorating the morbidity and mortality that occur as a result of YFV infection. It is anticipated that these model systems will help facilitate further improvements in the understanding of this virus and in furthering countermeasures to prevent or treat infections. Copyright © 2016 Elsevier B.V. All rights reserved.

  18. Cowpea viruses: Effect of single and mixed infections on symptomatology and virus concentration

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    Nsa Imade Y

    2007-09-01

    Full Text Available Abstract Natural multiple viral infections of cultivated cowpeas have been reported in Nigeria. In this study, three Nigerian commercial cowpea cultivars ("Olo 11", "Oloyin" and "White" and two lines from the IITA (IT86D- 719 and TVU 76 were mechanically inoculated with Cowpea aphid-borne mosaic virus (CABMV, Bean southern mosaic virus (SBMV and Cowpea mottle virus (CMeV singly, as well as in all possible combinations at 10, 20 and 30 days after planting (DAP. Samples of leaves or stems were collected at 10, 20 and 30 days after inoculation (DAI and analyzed for relative virus concentration by Enzyme-Linked Immunosrbent Assay. All the cultivars and lines {CVS/L} were susceptible to the viruses but the commercial CVS showed more severe symptoms and had relatively higher viral concentration. In single virus infections, CABMV which induced the most severe symptoms had absorbance values (at 405 nm of 0.11 to 0.46 while SBMV and CMeV which induced moderate symptoms had virus titre of 0.74 to 1.99 and 0.11 to 0.90 respectively. Plants inoculated 10 DAP had significantly higher virus concentration than those inoculated 30 DAP. In mixed infections involving CABMV (10 DAP apical necrosis and death were observed in commercial cultivars "Olo 11" and "White". Enhancement of CMeV titers were observed in plants infected with CMeV + CABMV. Multiple viral infections of cowpeas may result in complete yield loss, hence, the availability of seeds of cultivars with a high level of multiple virus resistance is recommended as a means of control.

  19. The yellow fever 17D vaccine virus as a vector for the expression of foreign proteins: development of new live flavivirus vaccines

    Directory of Open Access Journals (Sweden)

    Myrna C Bonaldo

    2000-01-01

    Full Text Available The Flaviviridae is a family of about 70 mostly arthropod-borne viruses many of which are major public health problems with members being present in most continents. Among the most important are yellow fever (YF, dengue with its four serotypes and Japanese encephalitis virus. A live attenuated virus is used as a cost effective, safe and efficacious vaccine against YF but no other live flavivirus vaccines have been licensed. The rise of recombinant DNA technology and its application to study flavivirus genome structure and expression has opened new possibilities for flavivirus vaccine development. One new approach is the use of cDNAs encopassing the whole viral genome to generate infectious RNA after in vitro transcription. This methodology allows the genetic mapping of specific viral functions and the design of viral mutants with considerable potential as new live attenuated viruses. The use of infectious cDNA as a carrier for heterologous antigens is gaining importance as chimeric viruses are shown to be viable, immunogenic and less virulent as compared to the parental viruses. The use of DNA to overcome mutation rates intrinsic of RNA virus populations in conjunction with vaccine production in cell culture should improve the reliability and lower the cost for production of live attenuated vaccines. The YF virus despite a long period ignored by researchers probably due to the effectiveness of the vaccine has made a come back, both in nature as human populations grow and reach endemic areas as well as in the laboratory being a suitable model to understand the biology of flaviviruses in general and providing new alternatives for vaccine development through the use of the 17D vaccine strain.

  20. An accurate, specific, sensitive, high-throughput method based on a microsphere immunoassay for multiplex detection of three viruses and bacterial fruit blotch bacterium in cucurbits.

    Science.gov (United States)

    Charlermroj, Ratthaphol; Makornwattana, Manlika; Himananto, Orawan; Seepiban, Channarong; Phuengwas, Sudtida; Warin, Nuchnard; Gajanandana, Oraprapai; Karoonuthaisiri, Nitsara

    2017-09-01

    To employ a microsphere immunoassay (MIA) to simultaneously detect multiple plant pathogens (potyviruses, Watermelon silver mottle virus, Melon yellow spot virus, and Acidovorax avenae subsp. citrulli) in actual plant samples, several factors need to be optimized and rigorously validated. Here, a simple extraction method using a single extraction buffer was successfully selected to detect the four pathogens in various cucurbit samples (cucumber, cantaloupe, melon, and watermelon). The extraction method and assay performance were validated with inoculated and field cucurbit samples. The MIA showed 98-99% relative accuracy, 97-100% relative specificity and 92-100% relative sensitivity when compared to commercial ELISA kits and reverse transcription PCR. In addition, the MIA was also able to accurately detect multiple-infected field samples. The results demonstrate that one common extraction method for all tested cucurbit samples could be applied to detect multiple pathogens; avoiding the need for multiple protocols to be employed. This multiplex method can therefore be instrumental for high-throughput screening of multiple plant pathogens with many advantages such as a shorter assay time (2.5h) with single assay format, a lower cost of detection ($5 vs $19.7 for 4 pathogens/sample) and less labor requirement. Its multiplex capacity can also be expanded to detect up to 50 different pathogens upon the availability of specific antibodies. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. [Investigation surrounding a fatal case of yellow fever in Côte d'Ivoire in 1999].

    Science.gov (United States)

    Akoua-Koffi, C; Diarrassouba, S; Bénié, V B; Ngbichi, J M; Bozoua, T; Bosson, A; Akran, V; Carnevale, P; Ehouman, A

    2001-08-01

    Côte d'Ivoire is an endemic country for yellow fever, but no case was officially notified in recent years. In July 1999, however, one fatal case was reported. A German citizen was infected in the national park of Comoe, in the north eastern area of the country. In order to evaluate the extent of amaril virus circulation and the risk for local people, a virological, entomological and epidemiological investigation was carried out by the ministry of health, the OCCGE, the Côte d'Ivoire Pasteur Institute (IPCI) and the World Health Organisation in the area where the fatal case had been staying. 18 suspected and 24 confirmed mosquito catchers were identified by interview and a blood specimen was collected from each of them. In addition, 159 batches of mosquitoes from which 94 batches of potential vectors were collected; among the suspected cases, 22% were immunised against yellow fever. Serological and virological analyses were made at IPCI and the Paris Pasteur Institute by ELISA technique and isolation on cells cultures and newborn mice. All the suspicious sera and 87.5% of the catchers were positive for IgG anti-amaril virus. One catcher's serum was positive for IgM anti-amaril virus. 11 suspected sera were positive for IgG anti-dengue virus with 1 positive for IgM. 1 strain of amaril virus and 3 strains of Zika virus were isolated from mosquitoes at IPCI and confirmed by CRORA in Dakar. These results indicated that there is a yellow fever and dengue virus are prevalent among the human and vector populations in the study area. Preventive measures must be adopted to protect human beings at risk for amaril infection.

  2. Implication of the Bacterial Endosymbiont Rickettsia spp. in Interactions of the Whitefly Bemisia tabaci with Tomato yellow leaf curl virus

    Science.gov (United States)

    Kliot, Adi; Cilia, Michelle; Czosnek, Henryk

    2014-01-01

    ABSTRACT Numerous animal and plant viruses are transmitted by arthropod vectors in a persistent, circulative manner. Tomato yellow leaf curl virus (TYLCV) is transmitted by the sweet potato whitefly Bemisia tabaci. We report here that infection with Rickettsia spp., a facultative endosymbiont of whiteflies, altered TYLCV-B. tabaci interactions. A B. tabaci strain infected with Rickettsia acquired more TYLCV from infected plants, retained the virus longer, and exhibited nearly double the transmission efficiency compared to an uninfected B. tabaci strain with the same genetic background. Temporal and spatial antagonistic relationships were discovered between Rickettsia and TYLCV within the whitefly. In different time course experiments, the levels of virus and Rickettsia within the insect were inversely correlated. Fluorescence in situ hybridization analysis of Rickettsia-infected midguts provided evidence for niche exclusion between Rickettsia and TYLCV. In particular, high levels of the bacterium in the midgut resulted in higher virus concentrations in the filter chamber, a favored site for virus translocation along the transmission pathway, whereas low levels of Rickettsia in the midgut resulted in an even distribution of the virus. Taken together, these results indicate that Rickettsia, by infecting the midgut, increases TYLCV transmission efficacy, adding further insights into the complex association between persistent plant viruses, their insect vectors, and microorganism tenants that reside within these insects. IMPORTANCE Interest in bacterial endosymbionts in arthropods and many aspects of their host biology in agricultural and human health systems has been increasing. A recent and relevant studied example is the influence of Wolbachia on dengue virus transmission by mosquitoes. In parallel with our recently studied whitefly-Rickettsia-TYLCV system, other studies have shown that dengue virus levels in the mosquito vector are inversely correlated with

  3. Real-time PCR protocols for the quantification of the begomovirus tomato yellow leaf curl Sardinia virus in tomato plants and in its insect vector.

    Science.gov (United States)

    Noris, Emanuela; Miozzi, Laura

    2015-01-01

    Tomato yellow leaf curl Sardinia virus (TYLCSV) (Geminiviridae) is an important pathogen, transmitted by the whitefly Bemisia tabaci, that severely affects the tomato production in the Mediterranean basin. Here, we describe real-time PCR protocols suitable for relative and absolute quantification of TYLCSV in tomato plants and in whitefly extracts. Using primers and probe specifically designed for TYLCSV, the protocols for relative quantification allow to compare the amount of TYLCSV present in different plant or whitefly samples, normalized to the amount of DNA present in each sample using endogenous tomato or Bemisia genes as internal references. The absolute quantification protocol allows to calculate the number of genomic units of TYLCSV over the genomic units of the plant host (tomato), with a sensitivity of as few as ten viral genome copies per sample. The described protocols are potentially suitable for several applications, such as plant breeding for resistance, analysis of virus replication, and virus-vector interaction studies.

  4. Rack-1, GAPDH3, and actin: proteins of Myzus persicae potentially involved in the transcytosis of beet western yellows virus particles in the aphid

    International Nuclear Information System (INIS)

    Seddas, Pascale; Boissinot, Sylvaine; Strub, Jean-Marc; Dorsselaer, Alain van; Regenmortel, Marc H.V. van; Pattus, Franc

    2004-01-01

    Beet western yellows virus (BWYV) is a Polerovirus that relies on the aphid Myzus persicae for its transmission, in a persistent-circulative mode. To be transmitted, the virus must cross the midgut and the accessory salivary glands (ASG) epithelial barriers in a transcytosis mechanism where vector receptors interact with virions. In this paper, we report in vitro interaction experiments between BWYV and aphid components. Using the M. persicae clone from Colmar, we showed that a set of aphid polypeptides, separated by SDS-PAGE or 2D electrophoresis (2DE), can bind in vitro to purified wild type or mutant particles. Using subcellular fractionation, we showed that the 65-kDa polypeptide identified as symbionin is a soluble protein whereas the other polypeptides seem to be associated more or less strongly to the membrane. We hypothesize that three polypeptides, identified by mass spectrometry as Rack-1, GAPDH3, and actin, may be involved in the epithelial transcytosis of virus particles in the aphid vector

  5. Factors affecting fat content in mottled ducks on the Upper Texas Gulf Coast

    Science.gov (United States)

    Kearns, Brian; Haukos, David A.; Walther, Patrick; Conway, Warren C.

    2014-01-01

    Body condition, or an individual's ability to address metabolic needs, is an important measure of organism health. For waterfowl, body condition, usually some measure of fat, provides a useful proxy for assessing energy budgets during different life history periods and potentially is a measure of response to ecosystem changes. The mottled duck (Anas fulvigula) is relatively poorly studied in respect to these dynamics and presents a unique case because its non-migratory life-history strategy releases it from metabolic costs experienced by many related migratory waterfowl species. Additionally, as a species in decline and of conservation concern in many parts of its range, traditional methods of fat content estimation that involve destructive sampling are less viable. The goal of this study was to produce an equation for estimating fat content in mottled ducks using birds (n = 24) donated at hunter-check stations or collected by law enforcement efforts on the Texas Chenier Plain National Wildlife Refuge Complex from 2005 - 2007. Morphometric measurements were taken, and ether extraction and fat removal was used to estimate percent body fat content and abdominal fat mass, respectively. A hierarchical simple linear regression modeling approach was used to determine external morphometrics that best predicted abdominal fat content. A ratio model based on body mass and a length metric (keel and wing chord length possessed equal model support) provided the best relationship with abdominal fat in sampled individuals. We then applied the regression equation to historical check station data to examine fluctuations in fat content over time; fat content or condition varied relatively little with the exception of years characterized by major disturbances. The mottled duck condition model created here can be used to better monitor population status and health without destructively sampling individuals.

  6. First full-length genome sequence of the polerovirus luffa aphid-borne yellows virus (LABYV) reveals the presence of at least two consensus sequences in an isolate from Thailand.

    Science.gov (United States)

    Knierim, Dennis; Maiss, Edgar; Kenyon, Lawrence; Winter, Stephan; Menzel, Wulf

    2015-10-01

    Luffa aphid-borne yellows virus (LABYV) was proposed as the name for a previously undescribed polerovirus based on partial genome sequences obtained from samples of cucurbit plants collected in Thailand between 2008 and 2013. In this study, we determined the first full-length genome sequence of LABYV. Based on phylogenetic analysis and genome properties, it is clear that this virus represents a distinct species in the genus Polerovirus. Analysis of sequences from sample TH24, which was collected in 2010 from a luffa plant in Thailand, reveals the presence of two different full-length genome consensus sequences.

  7. Reverse Transcription Polymerase Chain Reaction-based System for Simultaneous Detection of Multiple Lily-infecting Viruses

    Directory of Open Access Journals (Sweden)

    Ji Yeon Kwon

    2013-09-01

    Full Text Available A detection system based on a multiplex reverse transcription (RT polymerase chain reaction (PCR was developed to simultaneously identify multiple viruses in the lily plant. The most common viruses infecting lily plants are the cucumber mosaic virus (CMV, lily mottle virus (LMoV, lily symptomless virus (LSV. Leaf samples were collected at lily-cultivation facilities located in the Kangwon province of Korea and used to evaluate the detection system. Simplex and multiplex RT-PCR were performed using virus-specific primers to detect single-or mixed viral infections in lily plants. Our results demonstrate the selective detection of 3 different viruses (CMV, LMoV and LSV by using specific primers as well as the potential of simultaneously detecting 2 or 3 different viruses in lily plants with mixed infections. Three sets of primers for each target virus, and one set of internal control primers were used to evaluate the detection system for efficiency, reliability, and reproducibility.

  8. Incidence of viruses in fescue (Festuca sp.) seed production fields in the Willamette Valley in 2016

    Science.gov (United States)

    Tall Fescue seed production fields of Western Oregon were sampled and tested for the presence or absence of three viruses, Barley yellow dwarf virus (BYDV) -MAV and -PAV, and Cereal yellow dwarf virus (CYDV). There was no BYDV-MAV detected in any of the Fescue seed fields. The BYDV-PAV occurred in ...

  9. Selective constraints, molecular recombination structure and phylogenetic reconstruction of isometric plant RNA viruses of the families Luteoviridae and Tymoviridae.

    Science.gov (United States)

    Boulila, Moncef

    2011-02-01

    In an effort to enhance the knowledge on molecular evolution of currently the known members of the families Luteoviridae and Tymoviridae, in-depth molecular investigations in the entire genome of 147 accessions retrieved from the international databases, were carried out. Two algorithms (RECCO and RDP version 3.31β) adapted to the mosaic structure of viruses were utilized. The recombination frequency along the sequences was dissected and demonstrated that the three virus genera of the family Luteoviridae comprise numerous members subjected to recombination. It has pointed out that the major viruses swapped a few but long genomic segments. In addition, in Barley yellow dwarf virus, heredity material might be exchanged between two different serotypes. Even more, putative recombination events occurred between two different genera. Based on Fisher's Exact Test of Neutrality, positive selection acting on protein expression was detected only in the poleroviruses Cereal yellow dwarf virus, Potato leafroll virus and Wheat yellow dwarf virus. In contrast, several components of the family Tymoviridae were highly recombinant. Genomic portion exchange arose in many positions consisting of short fragments. Furthermore, no positive selection was detected. The evolutionary history showed, in the Luteoviridae, that all screened isolates split into three clusters corresponding to the three virus genera forming this family. Moreover, in the serotype PAV of Barley yellow dwarf virus, two major clades corresponding to PAV-USA and PAV-China, were delineated. Similarly, in the Tymoviridae, all analyzed isolates fell into four groups corresponding to the three virus genera composing this family along with the unclassified Tymoviridae. Inferred phylogenies reshuffled the existing classification and showed that Wheat yellow dwarf virus-RPV was genetically closely related to Cereal yellow dwarf virus and the unclassified Tymoviridae Grapevine syrah virus-1 constituted an integral part of

  10. Genome analysis of yellow fever virus of the ongoing outbreak in Brazil reveals polymorphisms

    Directory of Open Access Journals (Sweden)

    Myrna C Bonaldo

    Full Text Available The current yellow fever outbreak in Brazil is the most severe one in the country in recent times. It has rapidly spread to areas where YF virus (YFV activity has not been observed for more than 70 years and vaccine coverage is almost null. Here, we sequenced the whole YFV genome of two naturally infected howler-monkeys (Alouatta clamitans obtained from the Municipality of Domingos Martins, state of Espírito Santo, Brazil. These two ongoing-outbreak genome sequences are identical. They clustered in the 1E sub-clade (South America genotype I along with the Brazilian and Venezuelan strains recently characterised from infections in humans and non-human primates that have been described in the last 20 years. However, we detected eight unique amino acid changes in the viral proteins, including the structural capsid protein (one change, and the components of the viral replicase complex, the NS3 (two changes and NS5 (five changes proteins, that could impact the capacity of viral infection in vertebrate and/or invertebrate hosts and spreading of the ongoing outbreak.

  11. Concomitant outbreaks of yellow fever and hepatitis E virus in Darfur States, Sudan, 2012.

    Science.gov (United States)

    Ahmed, Sarah S; Soghaier, Mohammed A; Mohammed, Sozan; Khogali, Hayat S; Osman, Muntasir M; Abdalla, Abdalla M

    2016-01-31

    Yellow fever (YF) is a vector-borne disease transmitted to humans by infected Aedes mosquitoes, while hepatitis E virus (HEV) is a waterborne disease that is transmitted through the fecal-oral route. Both diseases have very close clinical presentation, namely fever, jaundice, malaise, and dark urine; they differ in severity and outcome. In this cross-sectional, laboratory-based study, an attempt was made to measure the correlation of concomitant YF and HEV infection in Darfur States during the previous YF outbreak in 2012. Results found concomitant outbreaks of YF and HEV at the same time with very weak statistical correlation between the two infections during the outbreak period, with Cramer's V correlation 0.05 and insignificant p value of 0.86. This correlation indicates that clinicians and care providers in tropical areas have to deal with clinical case definitions used for disease surveillance very carefully since prevalence of HEV infection is relatively common and this increases the possibility of misclassification and missing YF cases, particularly initial index cases, in a season or outbreak.

  12. Characterization of Brugmansia mosaic virus Isolated from Brugmansia spp. in Korea

    Directory of Open Access Journals (Sweden)

    Chung Youl Park

    2014-12-01

    Full Text Available In May 2013, an angel’s trumpet leaves showing mosaic and malformation symptoms were collected from Suwon city, Gyeonggi-do. An analysis of the collected sample by transmission electron microscopy observation showed filamentous rod particles of 720-800 nm in length. On the basis of the these observations, we performed PCR against three reported Potyviruses (Brugmansia mosaic virus, Colombian datura virus and Brugmansia suaveolens mottle virus, and the sample was positive for BruMV. Pathogenicity and host range test of BruMV was determined by mechanical inoculation. Solanaceae (tobacco, tomato and eggplant and Amaranthaceae (ground cherry appeared typical virus symptoms. To determine coat protein of this virus, we designed specific primer pairs, and performed PCR amplification, cloning, and sequencing. Phylogenetic analysis showed that BruMV-SW was most closely related to BruMV isolate SK. Comparison of the BruMV-SW coat protein nucleotide sequences showed 92% to 99% identities to the other BruMV isolates.

  13. Mechanosensory based orienting behaviors in fluvial and lacustrine populations of mottled sculpin (Cottus bairdi)

    Science.gov (United States)

    Sheryl Coombs; Gary D. Grossman

    2006-01-01

    We compared prey-orienting and rheotactic behaviors in a fluvial (Coweeta Creek) and lacustrine (Lake Michigan) population of mottled sculpin. Blinded sculpin from both populations exhibited unconditioned, mechanosensory based rheotaxis to low velocity flows. Whereas Lake Michigan sculpin generally showed increasing levels of positive rheotaxis to increasing velocities...

  14. Implication of the Whitefly Bemisia tabaci Cyclophilin B Protein in the Transmission of Tomato yellow leaf curl virus.

    Science.gov (United States)

    Kanakala, Surapathrudu; Ghanim, Murad

    2016-01-01

    Tomato yellow leaf curl virus (TYLCV) is a single-stranded (ssDNA) begomoviruses that causes severe damage to tomato and several other crops worldwide. TYLCV is exclusively transmitted by the sweetpotato whitefly, Bemisia tabaci in a persistent circulative and propagative manner. Previous studies have shown that the transmission, retention, and circulation of TYLCV in its vector involves interaction with insect and endosymbiont proteins, which aid in the transmission of the virus, or have a protective role in response to the presence of the virus in the insect body. However, only a low number of such proteins have been identified. Here, the role of B. tabaci Cyclophilin B (CypB) in the transmission of TYLCV protein was investigated. Cyclophilins are a large family of cellular prolyl isomerases that have many molecular roles including facilitating protein-protein interactions in the cell. One cyclophilin protein has been implicated in aphid-luteovirus interactions. We demonstrate that the expression of CypB from B. tabaci is altered upon TYLCV acquisition and retention. Further experiments used immunocapture-PCR and co-immunolocalization and demonstrated a specific interaction and colocalization between CypB and TYLCV in the the midgut, eggs, and salivary glands. Membrane feeding of anti-CypB antibodies and TYLCV-infected plants showed a decrease in TYLCV transmission, suggesting a critical role that CypB plays in TYLCV transmission. Further experiments, which used membrane feeding with the CypB inhibitor Cyclosporin A showed decrease in CypB-TYLCV colocalization in the midgut and virus transmission. Altogether, our results indicate that CypB plays an important role in TYLCV transmission by B. tabaci .

  15. Eclipta yellow vein virus enhances chlorophyll destruction, singlet oxygen production and alters endogenous redox status in Andrographis paniculata.

    Science.gov (United States)

    Khan, Asifa; Luqman, Suaib; Masood, Nusrat; Singh, Dhananjay Kumar; Saeed, Sana Tabanda; Samad, Abdul

    2016-07-01

    The infection of Eclipta yellow vein virus [EcYVV-IN, Accession No. KC476655], recently reported for the first time, on Andrographis paniculata was studied for redox-mediated alteration mechanism in infected plants. A. paniculata, an important medicinal plant, is used in traditional Indian, Chinese and modern system of medicine. Andrographolide, one of the foremost components of this plant, is known for its varied pharmacological properties. Our investigation provides insight into the effect of virus-induced changes in the singlet oxygen quenching due to the alteration in pigment content (chlorophyll and carotenoids) as well as activation of plant secondary metabolism along with defense activation leading to changes in enzymatic and non-enzymatic redox status. Due to infection, a reduction in carotenoid content was observed which leads to reduced quenching of singlet oxygen. An increased level of enzymatic (SOD and APX) and non-enzymatic antioxidant (DPPH, FRAP, RP, NO, TAC and TP) activities were also observed in virus-infected plants with a positive correlation (>0.9). However, CAT activity was diminished which could be either due to its proteolytic degradation or inactivation by superoxide anions (O(2-.)), NO or peroxynitrite radicals. A significant (p < 0.05) increase in total phenolic content was observed in the infected plants while no considerable difference was seen in the total flavonoid content. Our results highlighted the alteration in redox status caused by virus-induced biotic stress on the plants and could be useful for understanding the after effects of viral infection This study could also be helpful in developing biomimetic methods for improving the production of secondary metabolites of pharmaceutical importance. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  16. Implication of the whitefly Bemisia tabaci Cyclophilin B protein in the transmission of Tomato yellow leaf curl virus

    Directory of Open Access Journals (Sweden)

    Surapathrudu Kanakala

    2016-11-01

    Full Text Available Tomato yellow leaf curl virus (TYLCV is a single-stranded (ssDNA begomoviruses that causes severe damage to tomato and several other crops worldwide. TYLCV is exclusively transmitted by the sweetpotato whitefly, Bemisia tabaci in a persistent circulative and propagative manner. Previous studies have shown that the transmission, retention and circulation of TYLCV in its vector involves interaction with insect and endosymbiont proteins, which aid in the transmission of the virus, or have a protective role in response to the presence of the virus in the insect body. However, only a low number of such proteins have been identified. Here, the role of B. tabaci Cyclophilin B (CypB in the transmission of TYLCV protein was investigated. Cyclophilins (Cyps are a large family of cellular prolyl isomerases that have many molecular roles including facilitating protein-protein interactions in the cell. One cyclophilin protein has been implicated in aphid-luteovirus interactions. We demonstrate that the expression of CypB from B. tabaci is altered upon TYLCV acquisition and retention. Further experiments used immunocapture-PCR and co-immunolocalization and demonstrated a specific interaction and colocalization between CypB and TYLCV in the the midgut, eggs and salivary glands. Membrane feeding of anti-CypB antibodies and TYLCV infected plants showed a decrease in TYLCV transmission, suggesting a critical role that CypB plays in TYLCV transmission. Further experiments, which used membrane feeding with the CypB inhibitor Cyclosporin A (CsA showed decrease in CypB-TYLCV colocalization in the midgut and virus transmission. Altogether, our results indicate that CypB plays an important role in TYLCV transmission by B. tabaci.

  17. First report of a complete genome sequence for a begomovirus infecting Jatropha gossypifolia in the Americas.

    Science.gov (United States)

    Simmonds-Gordon, R N; Collins-Fairclough, A M; Stewart, C S; Roye, M E

    2014-10-01

    Jatropha gossypifolia is a weed that is commonly found with yellow mosaic symptoms growing along the roadside and in close proximity to cultivated crops in many farming communities in Jamaica. For the first time, the complete genome sequence of a new begomovirus, designated jatropha mosaic virus-[Jamaica:Spanish Town:2004] (JMV-[JM:ST:04]), was determined from field-infected J. gossypifolia in the western hemisphere. DNA-A nucleotide sequence comparisons showed closest identity (84 %) to two tobacco-infecting viruses from Cuba, tobacco mottle leaf curl virus-[Cuba:Sancti Spiritus:03] (TbMoLCV-[CU:SS:03]) and tobacco leaf curl Cuba virus-[Cuba:Taguasco:2005] (TbLCuCUV-[CU:Tag:05]), and two weed-infecting viruses from Cuba and Jamaica, Rhynchosia rugose golden mosaic virus-[Cuba:Camaguey:171:2009] (RhRGMV- [CU:Cam:171:09]) and Wissadula golden mosaic St. Thomas virus-[Jamaica:Albion:2005] (WGMSTV-[JM:Alb:05]). Phylogenetic analysis revealed that JMV-[JM:ST:04] is most closely related to tobacco and tomato viruses from Cuba and WGMSTV-[JM:Alb:05], a common malvaceous-weed-infecting virus from eastern Jamaica, and that it is distinct from begomoviruses infecting Jatropha species in India and Nigeria.

  18. Discovering Host Genes Involved in the Infection by the Tomato Yellow Leaf Curl Virus Complex and in the Establishment of Resistance to the Virus Using Tobacco Rattle Virus-based Post Transcriptional Gene Silencing

    Directory of Open Access Journals (Sweden)

    Rosa Lozano-Durán

    2013-03-01

    Full Text Available The development of high-throughput technologies allows for evaluating gene expression at the whole-genome level. Together with proteomic and metabolomic studies, these analyses have resulted in the identification of plant genes whose function or expression is altered as a consequence of pathogen attacks. Members of the Tomato yellow leaf curl virus (TYLCV complex are among the most important pathogens impairing production of agricultural crops worldwide. To understand how these geminiviruses subjugate plant defenses, and to devise counter-measures, it is essential to identify the host genes affected by infection and to determine their role in susceptible and resistant plants. We have used a reverse genetics approach based on Tobacco rattle virus-induced gene silencing (TRV-VIGS to uncover genes involved in viral infection of susceptible plants, and to identify genes underlying virus resistance. To identify host genes with a role in geminivirus infection, we have engineered a Nicotiana benthamiana line, coined 2IRGFP, which over-expresses GFP upon virus infection. With this system, we have achieved an accurate description of the dynamics of virus replication in space and time. Upon silencing selected N. benthamiana genes previously shown to be related to host response to geminivirus infection, we have identified eighteen genes involved in a wide array of cellular processes. Plant genes involved in geminivirus resistance were studied by comparing two tomato lines: one resistant (R, the other susceptible (S to the virus. Sixty-nine genes preferentially expressed in R tomatoes were identified by screening cDNA libraries from infected and uninfected R and S genotypes. Out of the 25 genes studied so far, the silencing of five led to the total collapse of resistance, suggesting their involvement in the resistance gene network. This review of our results indicates that TRV-VIGS is an exquisite reverse genetics tool that may provide new insights into the

  19. Divergence of host range and biological properties between natural isolate and full-length infectious cDNA clone of the Beet mild yellowing virus 2ITB.

    Science.gov (United States)

    Klein, Elodie; Brault, Véronique; Klein, Delphine; Weyens, Guy; Lefèbvre, Marc; Ziegler-Graff, Véronique; Gilmer, David

    2014-01-01

    Plant infection by poleroviruses is restricted to phloem tissues, preventing any classical leaf rub inoculation with viral RNA or virions. Efficient virus inoculation to plants is achieved by viruliferous aphids that acquire the virus by feeding on infected plants. The use of promoter-driven infectious cDNA is an alternative means to infect plants and allows reverse genetic studies to be performed. Using Beet mild yellowing virus isolate 2ITB (BMYV-2ITB), we produced a full-length infectious cDNA clone of the virus (named BMYV-EK) placed under the control of the T7 RNA polymerase and the Cauliflower mosaic virus 35S promoters. Infectivity of the engineered BMYV-EK virus was assayed in different plant species and compared with that of the original virus. We showed that in vitro- or in planta-derived transcripts were infectious in protoplasts and in whole plants. Importantly, the natural aphid vector Myzus persicae efficiently transmitted the viral progeny produced in infected plants. By comparing agroinoculation and aphid infection in a host range assay, we showed that the engineered BMYV-EK virus displayed a similar host range to BMYV-2ITB, except for Nicotiana benthamiana, which proved to be resistant to systemic infection with BMYV-EK. Finally, both the BMYV-EK P0 and the full-length clone were able to strongly interfere with post-transcriptional gene silencing. © 2013 BSPP AND JOHN WILEY & SONS LTD.

  20. Antibody array in a multiwell plate format for the sensitive and multiplexed detection of important plant pathogens.

    Science.gov (United States)

    Charlermroj, Ratthaphol; Himananto, Orawan; Seepiban, Channarong; Kumpoosiri, Mallika; Warin, Nuchnard; Gajanandana, Oraprapai; Elliott, Christopher T; Karoonuthaisiri, Nitsara

    2014-07-15

    The global seed market is considered to be an important industry with a total value of $10,543 million US dollars in 2012. Because plant pathogens such as bacteria and viruses cause a significant economic loss to both producers and exporters, the seed export industry urgently requires rapid, sensitive, and inexpensive testing for the pathogens to prevent disease spreading worldwide. This study developed an antibody array in a multiwell plate format to simultaneously detect four crucial plant pathogens, namely, a bacterial fruit blotch bacterium Acidovorax avenae subsp. citrulli (Aac), Chilli veinal mottle virus (ChiVMV, potyvirus), Watermelon silver mottle virus (WSMoV, tospovirus serogroup IV), and Melon yellow spot virus (MYSV, tospovirus). The capture antibodies specific to the pathogens were immobilized on each well at preassigned positions by an automatic microarrayer. The antibodies on the arrays specifically captured the corresponding pathogens present in the sample extracts. The presence of pathogens bound on the capture antibodies was subsequently detected by a cocktail of fluorescently conjugated secondary antibodies. The limits of detection of the developed antibody array for the detection of Aac, ChiVMV, WSMoV, and MYSV were 5 × 10(5) CFU/mL, 30 ng/mL, 1000 ng/mL, and 160 ng/mL, respectively, which were very similar to those of the conventional ELISA method. The antibody array in a multiwell plate format accurately detected plant pathogens in single and multiple detections. Moreover, this format enables easy handling of the assay at a higher speed of operation.

  1. Within-host dynamics of the emergence of Tomato yellow leaf curl virus recombinants.

    Directory of Open Access Journals (Sweden)

    Cica Urbino

    Full Text Available Tomato yellow leaf curl virus (TYLCV is a highly damaging begomovirus native to the Middle East. TYLCV has recently spread worldwide, recombining with other begomoviruses. Recent analysis of mixed infections between TYLCV and Tomato leaf curl Comoros begomovirus (ToLCKMV has shown that, although natural selection preserves certain co-evolved intra-genomic interactions, numerous and diverse recombinants are produced at 120 days post-inoculation (dpi, and recombinant populations from different tomato plants are very divergent. Here, we investigate the population dynamics that lead to such patterns in tomato plants co-infected with TYLCV and ToLCKMV either by agro-inoculation or using the natural whitefly vector Bemisia tabaci. We monitored the frequency of parental and recombinant genotypes independently in 35 plants between 18 and 330 dpi and identified 177 recombinants isolated at different times. Recombinants were detected from 18 dpi and their frequency increased over time to reach about 50% at 150 dpi regardless of the inoculation method. The distribution of breakpoints detected on 96 fully sequenced recombinants was consistent with a continuous generation of new recombinants as well as random and deterministic effects in their maintenance. A severe population bottleneck of around 10 genomes was estimated during early systemic infection-a phenomenon that could account partially for the heterogeneity in recombinant patterns observed among plants. The detection of the same recombinant genome in six of the thirteen plants analysed beyond 30 dpi supported the influence of selection on observed recombination patterns. Moreover, a highly virulent recombinant genotype dominating virus populations within one plant has, apparently, the potential to be maintained in the natural population according to its infectivity, within-host accumulation, and transmission efficiency - all of which were similar or intermediate to those of the parent genotypes. Our

  2. Simultaneous Detection of Barley Virus Diseases in Korea

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    Bong-Choon Lee

    2017-12-01

    Full Text Available Barley mild mosaic virus (BaMMV, Barley yellow mosaic virus (BaYMV and Barley yellow dwarf virus (BYDV have been identified as an important causative agents for an economically important disease of winter barley in Korea. In this study, a multiplex reverse transcription polymerase chain reaction (mRT-PCR method was used for the simultaneous detection. Three sets of virus-specific primers targeted to the capsid protein coding genes of BaMMV, BaYMV and BYDV were used to amplify fragments that were 594 bp, 461 bp, and 290 bp, respectively. Several sets of primers for each target virus were evaluated for their sensitivity and specificity by multiplex RT-PCR. The optimum primer concentrations and RT-PCR conditions were determined for the multiplex RT-PCR. The mRT-PCR assay was found to be a better and rapid virus diagnostic tool of specific barley diseases and potential for investigating the epidemiology of these viral diseases.

  3. The stress granule component G3BP is a novel interaction partner for the nuclear shuttle proteins of the nanovirus pea necrotic yellow dwarf virus and geminivirus abutilon mosaic virus.

    Science.gov (United States)

    Krapp, Susanna; Greiner, Eva; Amin, Bushra; Sonnewald, Uwe; Krenz, Björn

    2017-01-02

    Stress granules (SGs) are structures within cells that regulate gene expression during stress response, e.g. viral infection. In mammalian cells assembly of SGs is dependent on the Ras-GAP SH3-domain-binding protein (G3BP). The C-terminal domain of the viral nonstructural protein 3 (nsP3) of Semliki Forest virus (SFV) forms a complex with mammalian G3BP and sequesters it into viral RNA replication complexes in a manner that inhibits the formation of SGs. The binding domain of nsP3 to HsG3BP was mapped to two tandem 'FGDF' repeat motifs close to the C-terminus of the viral proteins. It was speculated that plant viruses employ a similar strategy to inhibit SG function. This study identifies an Arabidopsis thaliana NTF2-RRM domain-containing protein as a G3BP-like protein (AtG3BP), which localizes to plant SGs. Moreover, the nuclear shuttle protein (NSP) of the begomovirus abutilon mosaic virus (AbMV), which harbors a 'FVSF'-motif at its C-terminal end, interacts with the AtG3BP-like protein, as does the 'FNGSF'-motif containing NSP of pea necrotic yellow dwarf virus (PNYDV), a member of the Nanoviridae family. We therefore propose that SG formation upon stress is conserved between mammalian and plant cells and that plant viruses may follow a similar strategy to inhibit plant SG function as it has been shown for their mammalian counterparts. Copyright © 2016 Elsevier B.V. All rights reserved.

  4. Global yellow fever vaccination coverage from 1970 to 2016: an adjusted retrospective analysis.

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    Shearer, Freya M; Moyes, Catherine L; Pigott, David M; Brady, Oliver J; Marinho, Fatima; Deshpande, Aniruddha; Longbottom, Joshua; Browne, Annie J; Kraemer, Moritz U G; O'Reilly, Kathleen M; Hombach, Joachim; Yactayo, Sergio; de Araújo, Valdelaine E M; da Nóbrega, Aglaêr A; Mosser, Jonathan F; Stanaway, Jeffrey D; Lim, Stephen S; Hay, Simon I; Golding, Nick; Reiner, Robert C

    2017-11-01

    Substantial outbreaks of yellow fever in Angola and Brazil in the past 2 years, combined with global shortages in vaccine stockpiles, highlight a pressing need to assess present control strategies. The aims of this study were to estimate global yellow fever vaccination coverage from 1970 through to 2016 at high spatial resolution and to calculate the number of individuals still requiring vaccination to reach population coverage thresholds for outbreak prevention. For this adjusted retrospective analysis, we compiled data from a range of sources (eg, WHO reports and health-service-provider registeries) reporting on yellow fever vaccination activities between May 1, 1939, and Oct 29, 2016. To account for uncertainty in how vaccine campaigns were targeted, we calculated three population coverage values to encompass alternative scenarios. We combined these data with demographic information and tracked vaccination coverage through time to estimate the proportion of the population who had ever received a yellow fever vaccine for each second level administrative division across countries at risk of yellow fever virus transmission from 1970 to 2016. Overall, substantial increases in vaccine coverage have occurred since 1970, but notable gaps still exist in contemporary coverage within yellow fever risk zones. We estimate that between 393·7 million and 472·9 million people still require vaccination in areas at risk of yellow fever virus transmission to achieve the 80% population coverage threshold recommended by WHO; this represents between 43% and 52% of the population within yellow fever risk zones, compared with between 66% and 76% of the population who would have required vaccination in 1970. Our results highlight important gaps in yellow fever vaccination coverage, can contribute to improved quantification of outbreak risk, and help to guide planning of future vaccination efforts and emergency stockpiling. The Rhodes Trust, Bill & Melinda Gates Foundation, the

  5. Anamnestic immune response to dengue and decreased severity of yellow fever

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    Ricardo O Izurieta

    2009-01-01

    Full Text Available A protective immunity against yellow fever, from cross-reactive dengue antibodies, has been hypothesized as an explanation for the absence of yellow fever in Southern Asia where dengue immunity is almost universal. This study evaluates the association between protective immunity from cross-reactive dengue antibodies with yellow fever infection and severity of the disease. The study population consisted of military personnel of a jungle garrison and its detachments located in the Ecuadorian Amazonian rainforest. The cross-sectional study employed interviews as well as seroepidemiological methods. Humoral immune response to yellow fever, Mayaro, Venezuelan equine encephalitis, Oropouche, and dengue 2 infections was assessed by evaluating IgM and IgG specific antibodies. Log-linear regression analysis was used to evaluate age and presence of antibodies, against dengue type 2 virus, as predictors of yellow fever infection or severe disease. During the seroepidemiological survey, presence of dengue antibodies among yellow fever cases were observed in 77.3% cases from the coastal region, where dengue is endemic, 14.3% cases from the Amazon and 16.7 % cases from the Andean region. Dengue cross-reactive antibodies were not significantly associated with yellow fever infection but significantly associated with severity of the disease. The findings of this study suggest that previous exposure to dengue infection may have induced an anamnestic immune response that did not prevent yellow fever infection but greatly reduced the severity of the disease.

  6. The Yellow Fever Vaccine: A History

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    Frierson, J. Gordon

    2010-01-01

    After failed attempts at producing bacteria-based vaccines, the discovery of a viral agent causing yellow fever and its isolation in monkeys opened new avenues of research. Subsequent advances were the attenuation of the virus in mice and later in tissue culture; the creation of the seed lot system to avoid spontaneous mutations; the ability to produce the vaccine on a large scale in eggs; and the removal of dangerous contaminants. An important person in the story is Max Theiler, who was Prof...

  7. Regional variation in otolith Sr:Ca ratios of African longfinned eel Anguilla mossambica and mottled eel Anguilla marmorata: a challenge to the classic tool for reconstructing migratory histories of fishes.

    Science.gov (United States)

    Lin, Y-J; Jessop, B M; Weyl, O L F; Iizuka, Y; Lin, S-H; Tzeng, W-N; Sun, C-L

    2012-07-01

    Otolith Sr:Ca ratios of the African longfinned eel Anguilla mossambica and giant mottled eel Anguilla marmorata from nine freshwater sites in four rivers of South Africa were analysed to reconstruct their migratory life histories between freshwater and saltwater habitats. For A. mossambica, the Sr:Ca ratios in the otolith edge differed significantly among rivers and had large effect sizes, but did not differ among sites within a river. Otolith Sr:Ca ratios did not differ among rivers for A. marmorata. When rivers were pooled, the edge Sr:Ca ratios of A. mossambica were not significantly different from those of A. marmorata. According to the river-specific critical Sr:Ca ratio distinguishing freshwater from saltwater residence, most A. mossambica and A. marmorata had saltwater habitat experience after settlement in fresh water. This was primarily during their elver stage or early in the yellow eel stage. During the middle and late yellow eel stage, freshwater residency was preferred and only sporadic visits were made to saltwater habitats. The data also suggest that regional variations in otolith Sr:Ca ratios affect the critical Sr:Ca value and are a challenge for the reconstruction of migratory life histories that should be explicitly considered to avoid bias and uncertainty. © 2012 The Authors. Journal of Fish Biology © 2012 The Fisheries Society of the British Isles.

  8. Complete genome sequence analysis identifies a new genotype of brassica yellows virus that infects cabbage and radish in China.

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    Zhang, Xiao-Yan; Xiang, Hai-Ying; Zhou, Cui-Ji; Li, Da-Wei; Yu, Jia-Lin; Han, Cheng-Gui

    2014-08-01

    For brassica yellows virus (BrYV), proposed to be a member of a new polerovirus species, two clearly distinct genotypes (BrYV-A and BrYV-B) have been described. In this study, the complete nucleotide sequences of two BrYV isolates from radish and Chinese cabbage were determined. Sequence analysis suggested that these isolates represent a new genotype, referred to here as BrYV-C. The full-length sequences of the two BrYV-C isolates shared 93.4-94.8 % identity with BrYV-A and BrYV-B. Further phylogenetic analysis showed that the BrYV-C isolates formed a subgroup that was distinct from the BrYV-A and BrYV-B isolates based on all of the proteins except P5.

  9. Yellow Fever

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    ... Testing Vaccine Information Testing for Vaccine Adverse Events Yellow fever Vaccine Continuing Education Course Yellow Fever Home Prevention Vaccine Vaccine Recommendations Reactions to Yellow Fever Vacine Yellow Fever Vaccine, Pregnancy, & ... Transmission Symptoms, Diagnosis, & Treatment Maps Africa ...

  10. Bean Yellow Dwarf Virus replicons for high-level transgene expression in transgenic plants and cell cultures.

    Science.gov (United States)

    Zhang, Xiuren; Mason, Hugh

    2006-02-05

    A novel stable transgenic plant expression system was developed using elements of the replication machinery of Bean Yellow Dwarf Virus (BeYDV). The system contains two transgenes: 1) The BeYDV replicon vector with an expression cassette flanked by cis-acting DNA elements of BeYDV, and 2) The viral replication initiator protein (Rep) controlled by an alcohol-inducible promoter. When Rep expression was triggered by treatment with ethanol, it induced release of the BeYDV replicon from stably integrated T-DNA and episomal replication to high copy number. Replicon amplification resulted in substantially increased transgene mRNA levels (up to 80-fold) and translation products (up to 10-fold) after induction of Rep expression by ethanol treatment in tobacco NT1 cells and leaves of whole potato plants. Thus, the BeYDV stable transformant replicon system is a powerful tool for plant-based production of recombinant proteins. (c) 2005 Wiley Periodicals, Inc.

  11. Virus Nilam: Identifikasi, Karakter Biologi dan Fisik, Serta Upaya Pengendaliannya

    OpenAIRE

    Miftakhurohmah, Miftakhurohmah; Noveriza, Rita

    2015-01-01

    Infeksi virus pada tanaman nilam dapat menyebabkan penurunan produksi dan kualitas minyak. Sembilan jenis virus diidentifikasi menginfeksi tanaman nilam, yaitu Patchouli mosaic virus (PatMoV), Patchouli mild mosaic virus (PatMMV), Telosma mosaic virus (TeMV), Peanut stripe virus (PStV), Patchouli yellow mosaic virus (PatYMV), Tobacco necrosis virus (TNV), Broad bean wilt virus 2 (BBWV2), Cucumber mosaic virus (CMV), dan Cymbidium mosaic virus (CymMV). Kesembilan virus tersebut memiliki genom ...

  12. Survey of aphid population in a yellow passion fruit crop and its relationship on the spread Cowpea aphid-borne mosaic virus in a subtropical region of Brazil.

    Science.gov (United States)

    Garcêz, Renata Maia; Chaves, Alexandre Levi Rodrigues; Eiras, Marcelo; Meletti, Laura Maria Molina; de Azevedo Filho, Joaquim Adelino; da Silva, Leonardo Assis; Colariccio, Addolorata

    2015-01-01

    Passion fruit woodiness may be caused by Cowpea aphid-borne mosaic virus (CABMV) and is currently the major passion fruit disease in Brazil. To assess the virus-vector-host interactions, a newly introduced golden passion fruit plantation located in eastern region of São Paulo State, Brazil, was monitored. Dissemination of CABMV was determined analyzing golden passion fruit plants monthly for 18 months by PTA-ELISA. Seasonality and aphid fauna diversity was determined by identification of the captured species using yellow sticky, yellow water-pan and green tile traps. Population composition of the aphid species was determined using the descriptive index of occurrence, dominance and general classification and overlap of species in the R program. Analyses of species grouping afforded to recognize 14 aphid species. The genus Aphis represented 55.42 % of the species captured. Aphid species formed two distinct clusters, one of which was characterized by the diversity of polyphagous species that presented high potential to spread CABMV. The low abundance and diversity of aphid species did not interfere negatively in the CABMV epidemiology. The genus Aphis, particularly Aphis fabae/solanella and A. gossypii, was crucial in the spread of CABMV in passion fruit orchards in the eastern State of São Paulo.

  13. Characterization of Hungarian isolates of zucchini yellow mosaic virus (ZYMV, potyvirus) transmitted by seeds of Cucurbita pepo var Styriaca.

    Science.gov (United States)

    Tóbiás, István; Palkovics, László

    2003-04-01

    Zucchini yellow mosaic virus (ZYMV) has emerged as an important pathogen of cucurbits within the last few years in Hungary. The Hungarian isolates show a high biological variability, have specific nucleotide and amino acid sequences in the N-terminal region of coat protein and form a distinct branch in the phylogenetic tree. The virus is spread very efficiently in the field by several aphid species in a non-persistent manner. It can be transmitted by seed in holl-less seeded oil pumpkin (Cucurbita pepo (L) var Styriaca), although at a very low rate. Three isolates from seed transmission assay experiments were chosen and their nucleotide sequences of coat proteins have been compared with the available CP sequences of ZYMV. According to the sequence analysis, the Hungarian isolates belong to the Central European branch in the phylogenetic tree and, together with the ZYMV isolates from Austria and Slovenia, share specific amino acids at positions 16, 17, 27 and 37 which are characteristic only to these isolates. The phylogenetic tree suggests the common origin of distantly distributed isolates which can be attributed to widespread seed transmission.

  14. Travel characteristics and yellow fever vaccine usage among US Global TravEpiNet travelers visiting countries with risk of yellow fever virus transmission, 2009-2011.

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    Jentes, Emily S; Han, Pauline; Gershman, Mark D; Rao, Sowmya R; LaRocque, Regina C; Staples, J Erin; Ryan, Edward T

    2013-05-01

    Yellow fever (YF) vaccine-associated serious adverse events and changing YF epidemiology have challenged healthcare providers to vaccinate only travelers whose risk of YF during travel is greater than their risk of adverse events. We describe the travel characteristics and YF vaccine use among US travelers visiting Global TravEpiNet clinics from January of 2009 to March of 2011. Of 16,660 travelers, 5,588 (34%) had itineraries to areas with risk of YF virus transmission. Of those travelers visiting one country with YF risk (N = 4,517), 71% were vaccinated at the visit, and 20% were presumed to be immune from prior vaccination. However, travelers visiting friends and relatives (odds ratio [OR] = 2.57, 95% confidence interval [95% CI] = 1.27-5.22) or going to Nigeria (OR = 3.01, 95% CI = 1.37-6.62) were significantly more likely to decline vaccination. To optimize YF vaccine use, clinicians should discuss an individual's risk-benefit assessment of vaccination and close knowledge gaps regarding vaccine use among at-risk populations.

  15. An individual-based simulation model for mottled sculpin (Cottus bairdi) in a southern Appalachian stream

    Science.gov (United States)

    Brenda Rashleigh; Gary D. Grossman

    2005-01-01

    We describe and analyze a spatially explicit, individual-based model for the local population dynamics of mottled sculpin (Cottus bairdi). The model simulated daily growth, mortality, movement and spawning of individuals within a reach of stream. Juvenile and adult growth was based on consumption bioenergetics of benthic macroinvertebrate prey;...

  16. Fever versus Fever: the role of host and vector susceptibility and interspecific competition in shaping the current and future distributions of the sylvatic cycles of dengue virus and yellow fever virus

    Science.gov (United States)

    Hanley, Kathryn A.; Monath, Thomas P.; Weaver, Scott C.; Rossi, Shannan L.; Richman, Rebecca L.; Vasilakis, Nikos

    2013-01-01

    Two different species of flaviviruses, dengue virus (DENV) and yellow fever virus (YFV), that originated in sylvatic cycles maintained in non-human primates and forest-dwelling mosquitoes have emerged repeatedly into sustained human-to-human transmission by Aedes aegypti mosquitoes. Sylvatic cycles of both viruses remain active, and where the two viruses overlap in West Africa they utilize similar suites of monkeys and Aedes mosquitoes. These extensive similarities render the differences in the biogeography and epidemiology of the two viruses all the more striking. First, the sylvatic cycle of YFV originated in Africa and was introduced into the New World, probably as a result of the slave trade, but is absent in Asia; in contrast, sylvatic DENV likely originated in Asia and has spread to Africa but not to the New World. Second, while sylvatic YFV can emerge into extensive urban outbreaks in humans, these invariably die out, whereas four different types of DENV have established human transmission cycles that are ecologically and evolutionarily distinct from their sylvatic ancestors. Finally, transmission of YFV among humans has been documented only in Africa and the Americas, whereas DENV is transmitted among humans across most of the range of competent Aedes vectors, which in the last decade has included every continent save Antarctica. This review summarizes current understanding of sylvatic transmission cycles of YFV and DENV, considers possible explanations for their disjunct distributions, and speculates on the potential consequences of future establishment of a sylvatic cycle of DENV in the Americas. PMID:23523817

  17. Guiding dengue vaccine development using knowledge gained from the success of the yellow fever vaccine.

    Science.gov (United States)

    Liang, Huabin; Lee, Min; Jin, Xia

    2016-01-01

    Flaviviruses comprise approximately 70 closely related RNA viruses. These include several mosquito-borne pathogens, such as yellow fever virus (YFV), dengue virus (DENV), and Japanese encephalitis virus (JEV), which can cause significant human diseases and thus are of great medical importance. Vaccines against both YFV and JEV have been used successfully in humans for decades; however, the development of a DENV vaccine has encountered considerable obstacles. Here, we review the protective immune responses elicited by the vaccine against YFV to provide some insights into the development of a protective DENV vaccine.

  18. Barley yellow dwarf virus Infection Leads to Higher Chemical Defense Signals and Lower Electrophysiological Reactions in Susceptible Compared to Tolerant Barley Genotypes.

    Science.gov (United States)

    Paulmann, Maria K; Kunert, Grit; Zimmermann, Matthias R; Theis, Nina; Ludwig, Anatoli; Meichsner, Doreen; Oelmüller, Ralf; Gershenzon, Jonathan; Habekuss, Antje; Ordon, Frank; Furch, Alexandra C U; Will, Torsten

    2018-01-01

    Barley yellow dwarf virus (BYDV) is a phloem limited virus that is persistently transmitted by aphids. Due to huge yield losses in agriculture, the virus is of high economic relevance. Since the control of the virus itself is not possible, tolerant barley genotypes are considered as the most effective approach to avoid yield losses. Although several genes and quantitative trait loci are known and used in barley breeding for virus tolerance, little is known about molecular and physiological backgrounds of this trait. Therefore, we compared the anatomy and early defense responses of a virus susceptible to those of a virus-tolerant cultivar. One of the very early defense responses is the transmission of electrophysiological reactions. Electrophysiological reactions to BYDV infection might differ between susceptible and tolerant cultivars, since BYDV causes disintegration of sieve elements in susceptible cultivars. The structure of vascular bundles, xylem vessels and sieve elements was examined using microscopy. All three were significantly decreased in size in infected susceptible plants where the virus causes disintegration of sieve elements. This could be associated with an uncontrolled ion exchange between the sieve-element lumen and apoplast. Further, a reduced electrophysiological isolation would negatively affect the propagation of electrophysiological reactions. To test the influence of BYDV infection on electrophysiological reactions, electropotential waves (EPWs) induced by leaf-tip burning were recorded using aphids as bioelectrodes. EPWs in infected susceptible plants disappeared already after 10 cm in contrast to those in healthy susceptible or infected tolerant or healthy tolerant plants. Another early plant defense reaction is an increase in reactive oxygen species (ROS). Using a fluorescent dye, we found a significant increase in ROS content in infected susceptible plants but not in infected tolerant plants. Similar results were found for the

  19. AP2/ERF Transcription Factors Involved in Response to Tomato Yellow Leaf Curly Virus in Tomato

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    Ying Huang

    2016-07-01

    Full Text Available Tomato yellow leaf curly virus (TYLCV, transmitted by the whitefly (, causes leaf curling and yellowing, plant dwarfism, and growth inhibition in tomato ( L.. The APETALA2 (AP2 and ethylene response factor (ERF transcription factor (TF family, the largest plant-specific TF family, was identified to function in plant development and pathogen defense. Our study aimed to analyze the mechanism underlying the function of ERF (SlERF TFs in response to TYLCV infection and improve useful information to increase the resistance to TYLCV in tomato. A total of 22 tomato AP2/ERF TFs in response to TYLCV were identified according to transcriptome database. Five ERF-B3 TFs were identified in cultivars Hongbeibei (highly resistant, Zheza-301, Zhefen-702 (both resistant, Jinpeng-1, and Xianke-6 (both susceptible. Interaction network indicated that SlERF TFs could interact with mitogen-activated protein kinase (MAPK. Expression profiles of five ERF-B3 genes (, , , , and were detected by quantitative real-time–polymerase chain reaction (qRT-PCR after TYLCV infection in five tomato cultivars. expression was upregulated in five tomato cultivars. The expressions of three genes (, , and were upregulated in Zheza-301 and Zhefen-702. and expressions were downregulated in Hongbeibei and Xianke-6, respectively. Yeast one-hybrid showed that the GCC-box binding ability of ERF-B3 TFs differed in resistant and susceptible tomato cultivars. Expression profiles were related to the GCC-box binding ability of SlERF TFs in resistant and susceptible tomato cultivars. The defense mechanism underlying the tomato’s response to TYLCV involved a complicated network, which provided important information for us in breeding and genetic analysis.

  20. AEGY-28 Cell Line of Aedes aegypti (Diptera Culicidae is Infection Refractory to Dengue 2 and Yellow Fever Virus

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    Nadia Y. Castañeda

    2007-07-01

    Full Text Available Mosquito cell derived cultures are useful tools for arbovirus isolation, identification or characterization. For studying dengue (DENV and yellow fever viruses (YFV Aedes albopictus C6/36 or Aedes pseudoscutellaris AP-61 cell lines, are normally used. The Aedes aegypti AEGY-28 cell line was obtained from embryonic tissues and characterized previously by one of us. In order to evaluate its susceptibility to two Flavivirus, AEGY- 28 cells were inoculated with different multiplicity of infection (MOI with type 2 DENV (COL-789, MOI: 1 and 5 and YFV clinical isolates (V-341, MOI 0,02 then processed at different times post infection (p.i.. Immunostai ning and fluorometric cell-ELISA were carried out to identify and quantify viral antigens. C6/36 and Vero cells were used as positive controls. Unexpectedly, immunoreactivity was not found in inoculated AEGY-28 cells, even in higher MOI or late times p.i., therefore antigen quantification using fluorometric cell-ELISA were not  plausible. Reverse transcriptase PCR with specific primers did not detect viral RNA in AEGY-28 inoculated cells. We can conclude that Aedes aegypti AEGY-28 cell line is not susceptible to dengue and yellow fever Flavivirus, a finding possibly related with the lacking of specific molecules at the plasma membrane or absence of cell machinery necessary for viral replication.

  1. Yellow fever 17D-vectored vaccines expressing Lassa virus GP1 and GP2 glycoproteins provide protection against fatal disease in guinea pigs.

    Science.gov (United States)

    Jiang, Xiaohong; Dalebout, Tim J; Bredenbeek, Peter J; Carrion, Ricardo; Brasky, Kathleen; Patterson, Jean; Goicochea, Marco; Bryant, Joseph; Salvato, Maria S; Lukashevich, Igor S

    2011-02-01

    Yellow Fever (YF) and Lassa Fever (LF) are two prevalent hemorrhagic fevers co-circulating in West Africa and responsible for thousands of deaths annually. The YF vaccine 17D has been used as a vector for the Lassa virus glycoprotein precursor (LASV-GPC) or their subunits, GP1 (attachment glycoprotein) and GP2 (fusion glycoprotein). Cloning shorter inserts, LASV-GP1 and -GP2, between YF17D E and NS1 genes enhanced genetic stability of recombinant viruses, YF17D/LASV-GP1 and -GP2, in comparison with YF17D/LASV-GPC recombinant. The recombinant viruses were replication competent and properly processed YF proteins and LASV GP antigens in infected cells. YF17D/LASV-GP1 and -GP2 induced specific CD8+ T cell responses in mice and protected strain 13 guinea pigs against fatal LF. Unlike immunization with live attenuated reassortant vaccine ML29, immunization with YF17D/LASV-GP1 and -GP2 did not provide sterilizing immunity. This study demonstrates the feasibility of YF17D-based vaccine to control LF in West Africa. Copyright © 2010 Elsevier Ltd. All rights reserved.

  2. Yellow fever 17D-vectored vaccines expressing Lassa virus GP1 and GP2 glycoproteins provide protection against fatal disease in guinea pigs

    Science.gov (United States)

    Jiang, Xiaohong; Dalebout, Tim J.; Bredenbeek, Peter J.; Carrion, Ricardo; Brasky, Kathleen; Patterson, Jean; Goicochea, Marco; Bryant, Joseph; Salvato, Maria S.; Lukashevich, Igor S.

    2010-01-01

    Yellow Fever (YF) and Lassa Fever (LF) are two prevalent hemorrhagic fevers co-circulating in West Africa and responsible for thousands of deaths annually. The YF vaccine 17D has been used as a vector for the Lassa virus glycoprotein precursor (LASV-GPC) or their subunits, GP1 (attachment glycoprotein) and GP2 (fusion glycoprotein). Cloning shorter inserts, LASV GP1 and GP2, between YF17D E and NS1 genes enhanced genetic stability of recombinant viruses, YF17D/LASV-GP1 and –GP2, in comparison with YF17D/LASV-GPC recombinant. The recombinant viruses were replication competent and properly processed YF and LASV GP proteins in infected cells. YF17D/LASV-GP1&GP2 induced specific CD8+ T cell responses in mice and protected strain 13 guinea pigs against fatal LF. Unlike immunization with live attenuated reassortant vaccine ML29, immunization with YF17D/LASV-GP1&GP2 did not provide sterilizing immunity. This study demonstrates the feasibility of YF17D-based vaccine to control LF in West Africa. PMID:21145373

  3. Annulate lamellae in phloem cells of virus-infected Sonchus plants.

    Science.gov (United States)

    Steinkamp, M P; Hoefert, L L

    1977-07-01

    The occurrence of annulate lamellae (AL) in differentiating phloem of Sonchus oleraceus (Compositae) singly infected with sowthistle yellow vein virus (SYVV) and doubly infected with a combination of SYVV and beet yellow stunt virus is documented by electron microscopy. Cell types in which AL were found were immature sieve elements and phloem parenchyma cells. AL were found only in cells that also contained SYVV particles although a direct association between the virus and AL was not apparent. The substructure of the AL and the relationships between the AL and the nuclear envelope and endoplasmic reticulum are similar to those reported in other descriptions of this organelle in the literature. This report appears to be the first one concerning the association of AL with a plant virus disease.

  4. Isolation of yellow fever virus (YFV from naturally infectied Haemagogus (Conopostegus leucocelaenus (diptera, cukicudae in São Paulo State, Brazil, 2009

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    Renato Pereira de Souza

    2011-06-01

    Full Text Available After detecting the death of Howlers monkeys (genus Alouatta and isolation of yellow fever virus (YFV in Buri county, São Paulo, Brazil, an entomological research study in the field was started. A YFV strain was isolated from newborn Swiss mice and cultured cells of Aedes albopictus - C6/36, from a pool of six Haemagogus (Conopostegus leucocelaenus (Hg. leucocelaenus mosquitoes (Dyar & Shannon collected at the study site. Virus RNA fragment was amplified by RT-PCR and sequenced. The MCC Tree generated showed that the isolated strain is related to the South American I genotype, in a monophyletic clade containing isolates from recent 2008-2010 epidemics and epizootics in Brazil. Statistical analysis commonly used were calculated to characterize the sample in relation to diversity and dominance and indicated a pattern of dominance of one or a few species. Hg. leucocelaenus was found infected in Rio Grande do Sul State as well. In São Paulo State, this is the first detection of YFV in Hg. leucocelaenus.

  5. Yellow fever virus isolated from a fatal post vaccination event: an experimental comparative study with the 17DD vaccine strain in the Syrian hamster (Mesocricetus auratus

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    Sueli Guerreiro Rodrigues

    2004-01-01

    Full Text Available In order to investigate the pathogenicity of the virus strain GOI 4191 that was isolated from a fatal adverse event after yellow fever virus (YFV vaccination, an experimental assay using hamsters (Mesocricetus auratus as animal model and YFV 17DD vaccine strain as virus reference was accomplished. The two virus strains were inoculated by intracerebral, intrahepatic and subcutaneous routes. The levels of viremia, antibody response, and aminotransferases were determined in sera; while virus, antigen and histopathological changes were determined in the viscera. No viremia was detected for either strain following infection; the immune response was demonstrated to be more effective to strain GOI 4191; and no significant aminotransferase levels alterations were detected. Strain GOI 4191 was recovered only from the brain of animals inoculated by the IC route. Viral antigens were detected in liver and brain by immunohistochemical assay. Histothological changes in the viscera were characterized by inflammatory infiltrate, hepatocellular necrosis, and viral encephalitis. Histological alterations and detection of viral antigen were observed in the liver of animals inoculated by the intrahepatic route. These findings were similar for both strains used in the experiment; however, significant differences were observed from those results previously reported for wild type YFV strains.

  6. Yellow fever in Brazil: thoughts and hypotheses on the emergence in previously free areas

    Directory of Open Access Journals (Sweden)

    Pedro Fernando da Costa Vasconcelos

    2010-12-01

    Full Text Available This article describes and discusses factors associated to the reemergence of yellow fever and its transmission dynamics in the states of São Paulo (Southeastern Brazil and Rio Grande do Sul (Southern during 2008 and 2009. The following factors have played a pivotal role for the reemergence of yellow fever in these areas: large susceptible human population; high prevalence of vectors and primary hosts (non-human primates; favorable climate conditions, especially increased rainfall; emergence of a new genetic lineage; and circulation of people and/or monkeys infected by virus. There is a need for an effective surveillance program to prevent the reemergence of yellow fever in other Brazilian states.

  7. Travel Characteristics and Yellow Fever Vaccine Usage Among US Global TravEpiNet Travelers Visiting Countries with Risk of Yellow Fever Virus Transmission, 2009–2011

    Science.gov (United States)

    Jentes, Emily S.; Han, Pauline; Gershman, Mark D.; Rao, Sowmya R.; LaRocque, Regina C.; Staples, J. Erin; Ryan, Edward T.

    2013-01-01

    Yellow fever (YF) vaccine-associated serious adverse events and changing YF epidemiology have challenged healthcare providers to vaccinate only travelers whose risk of YF during travel is greater than their risk of adverse events. We describe the travel characteristics and YF vaccine use among US travelers visiting Global TravEpiNet clinics from January of 2009 to March of 2011. Of 16,660 travelers, 5,588 (34%) had itineraries to areas with risk of YF virus transmission. Of those travelers visiting one country with YF risk (N = 4,517), 71% were vaccinated at the visit, and 20% were presumed to be immune from prior vaccination. However, travelers visiting friends and relatives (odds ratio [OR] = 2.57, 95% confidence interval [95% CI] = 1.27–5.22) or going to Nigeria (OR = 3.01, 95% CI = 1.37–6.62) were significantly more likely to decline vaccination. To optimize YF vaccine use, clinicians should discuss an individual's risk–benefit assessment of vaccination and close knowledge gaps regarding vaccine use among at-risk populations. PMID:23458961

  8. [Investigation of dengue virus and yellow fever virus seropositivities in blood donors from Central/Northern Anatolia, Turkey].

    Science.gov (United States)

    Ergünay, Koray; Saygan, Mehmet B; Aydoğan, Sibel; Litzba, Nadine; Niedrig, Matthias; Pınar, Ahmet; Us, Dürdal

    2010-07-01

    Dengue virus (DENV) and yellow fever virus (YFV) are two of the globally prevalent vector-borne flaviviruses. Data on these viruses from Turkey is limited to a single study originating from the western, Aegean region of Turkey, where evidence for DENV exposure had been confirmed in residents and presence of hemagglutination inhibiting antibodies against YFV had been revealed. The aim of this study was to investigate the rates of seropositivity of DENV and YFV in blood donors from Central/Northern Anatolia, Turkey, for the demonstration of possible human exposure. Serum samples were collected by the Turkish Red Crescent Middle Anatolia Regional Blood Center from donation sites at Ankara, Konya, Eskişehir and Zonguldak provinces and included in the study after informed consent. Ankara is the capital and second most-populated city in Turkey. All samples were previously evaluated for West Nile and tick-borne encephalitis virus antibodies and found to be negative. A total of 2435 and 1502 sera have been evaluated for IgG antibodies against DENV and YFV, respectively. Commercial enzymelinked immunosorbent assays (ELISAs) and indirect immunofluorescence tests (IIFTs) were applied (Euroimmun, Germany) for DENV/YFV IgG surveillance. DENV IgG reactive sera were further evaluated for IgM by ELISA and a commercial mosaic IIFT to determine DENV subtypes. IgM positive samples were also analyzed by a commercial NS1 antigen detection assay (Bio-Rad Laboratories, France). YFV IgG reactive samples were evaluated by IIFT for IgM and via mosaic IIFT and antibody specificity were confirmed by plaque reduction neutralization test (PRNT). Anti-DENV IgGs were demonstrated in repeated assays in 0.9% (21/2435) of the sera. In two samples with borderline IgG results, presence of DENV IgM was detected, one of which was also borderline positive for DENV NS1 antigen. In 14.3% (3/21) of the IgG reactive sera, mosaic IIFT was evaluated as positive and displayed prominent reactivity for DENV-2 in

  9. Top 10 plant viruses in molecular plant pathology.

    Science.gov (United States)

    Scholthof, Karen-Beth G; Adkins, Scott; Czosnek, Henryk; Palukaitis, Peter; Jacquot, Emmanuel; Hohn, Thomas; Hohn, Barbara; Saunders, Keith; Candresse, Thierry; Ahlquist, Paul; Hemenway, Cynthia; Foster, Gary D

    2011-12-01

    Many scientists, if not all, feel that their particular plant virus should appear in any list of the most important plant viruses. However, to our knowledge, no such list exists. The aim of this review was to survey all plant virologists with an association with Molecular Plant Pathology and ask them to nominate which plant viruses they would place in a 'Top 10' based on scientific/economic importance. The survey generated more than 250 votes from the international community, and allowed the generation of a Top 10 plant virus list for Molecular Plant Pathology. The Top 10 list includes, in rank order, (1) Tobacco mosaic virus, (2) Tomato spotted wilt virus, (3) Tomato yellow leaf curl virus, (4) Cucumber mosaic virus, (5) Potato virus Y, (6) Cauliflower mosaic virus, (7) African cassava mosaic virus, (8) Plum pox virus, (9) Brome mosaic virus and (10) Potato virus X, with honourable mentions for viruses just missing out on the Top 10, including Citrus tristeza virus, Barley yellow dwarf virus, Potato leafroll virus and Tomato bushy stunt virus. This review article presents a short review on each virus of the Top 10 list and its importance, with the intent of initiating discussion and debate amongst the plant virology community, as well as laying down a benchmark, as it will be interesting to see in future years how perceptions change and which viruses enter and leave the Top 10. © 2011 The Authors. Molecular Plant Pathology © 2011 BSPP and Blackwell Publishing Ltd.

  10. Effect of Raspberry bushy dwarf virus, Raspberry leaf mottle virus, and Raspberry latent virus on plant growth and fruit crumbliness in ‘Meeker’ red Raspberry

    Science.gov (United States)

    Raspberry crumbly fruit in red raspberry (Rubus idaeus L.), widespread in the Pacific Northwest of the United States and British Columbia, Canada, is most commonly caused by a virus infection. Raspberry bushy dwarf virus (RBDV) has long been attributed as the causal agent of the disease. Recently, t...

  11. Analysis of viral (zucchini yellow mosaic virus) genetic diversity during systemic movement through a Cucurbita pepo vine.

    Science.gov (United States)

    Dunham, J P; Simmons, H E; Holmes, E C; Stephenson, A G

    2014-10-13

    Determining the extent and structure of intra-host genetic diversity and the magnitude and impact of population bottlenecks is central to understanding the mechanisms of viral evolution. To determine the nature of viral evolution following systemic movement through a plant, we performed deep sequencing of 23 leaves that grew sequentially along a single Cucurbita pepo vine that was infected with zucchini yellow mosaic virus (ZYMV), and on a leaf that grew in on a side branch. Strikingly, of 112 genetic (i.e. sub-consensus) variants observed in the data set as a whole, only 22 were found in multiple leaves. Similarly, only three of the 13 variants present in the inoculating population were found in the subsequent leaves on the vine. Hence, it appears that systemic movement is characterized by sequential population bottlenecks, although not sufficient to reduce the population to a single virion as multiple variants were consistently transmitted between leaves. In addition, the number of variants within a leaf increases as a function of distance from the inoculated (source) leaf, suggesting that the circulating sap may serve as a continual source of virus. Notably, multiple mutational variants were observed in the cylindrical inclusion (CI) protein (known to be involved in both cell-to-cell and systemic movement of the virus) that were present in multiple (19/24) leaf samples. These mutations resulted in a conformational change, suggesting that they might confer a selective advantage in systemic movement within the vine. Overall, these data reveal that bottlenecks occur during systemic movement, that variants circulate in the phloem sap throughout the infection process, and that important conformational changes in CI protein may arise during individual infections. Copyright © 2014 Elsevier B.V. All rights reserved.

  12. An epidemic of sylvatic yellow fever in the southeast region of Maranhao State, Brazil, 1993-1994: epidemiologic and entomologic findings.

    Science.gov (United States)

    Vasconcelos, P F; Rodrigues, S G; Degallier, N; Moraes, M A; da Rosa, J F; da Rosa, E S; Mondet, B; Barros, V L; da Rosa, A P

    1997-08-01

    Yellow fever virus transmission was very active in Maranhao State in Brazil in 1993 and 1994. An investigation was carried out to evaluate the magnitude of the epidemic. In 1993, a total of 932 people was examined for yellow fever from Maranhao: 70 were positive serologically, histopathologically, and/or by virus isolation, and another four cases were diagnosed clinically and epidemiologically. In Mirador (17,565 inhabitants), the incidence was 3.5 per 1,000 people (case fatality rate [number of deaths/number of cases diagnosed] = 16.4%), while in a rural yellow fever risk area (14,659 inhabitants), the incidence was 4.2 and the case-fatality rate was 16.1% (10 of 62). A total of 45.2% (28 of 62) asymptomatic infections were registered. In 1994, 49 serum samples were obtained and 16 cases were confirmed (two by virus isolation, two by seroconversion, and 12 by serology). No fatal cases were reported. In 1993, 936 potential yellow fever vectors were captured in Mirador and a single strain was isolated from a pool of Haemagogus janthinomys (infection rate = 0.16%). In 1994, 16 strains were isolated from 1,318 Hg. janthinomys (infection rate = 1.34%) and one Sabethes chloropterus (infection rate = 1.67%). Our results suggest that this was the most extensive outbreak of yellow fever in the last 20 years in Brazil. It is also clear that the lack of vaccination was the principal reason for the epidemic, which occurred between April and June, during the rainy season, a period in which the mosquito population in the forest increases.

  13. Optimization of Newcastle disease virus production in T-flask

    African Journals Online (AJOL)

    GREGORY

    2011-12-16

    Dec 16, 2011 ... In the present study, the production of lentogenic Asplin F strain of Newcastle disease virus by ... future live Newcastle disease vaccine production in larger ..... Production of yellow fever virus in microcarrier-based Vero cell ...

  14. Protection of melon plants against Cucumber mosaic virus infection ...

    African Journals Online (AJOL)

    This study was carried out to characterize a virus causing severe mosaic, yellowing, stunting and leaf deformation on melon (Cucumis melo L.), and evaluate the capacity of Pseudomonas fluorescens as biofertilizer to improve plant growth and restrict the accumulation of the virus in the plant. The virus was identified as an ...

  15. Live Virus Vaccines Based on a Yellow Fever Vaccine Backbone: Standardized Template with Key Considerations for a Risk/Benefit Assessment*

    Science.gov (United States)

    Monath, Thomas P.; Seligman, Stephen J.; Robertson, James S.; Guy, Bruno; Hayes, Edward B.; Condit, Richard C.; Excler, Jean Louis; Mac, Lisa Marie; Carbery, Baevin; Chen, Robert T

    2015-01-01

    The Brighton Collaboration Viral Vector Vaccines Safety Working Group (V3SWG) was formed to evaluate the safety of live, recombinant viral vaccines incorporating genes from heterologous viruses inserted into the backbone of another virus (so-called “chimeric virus vaccines”). Many viral vector vaccines are in advanced clinical trials. The first such vaccine to be approved for marketing (to date in Australia, Thailand, Malaysia, and the Philippines) is a vaccine against the flavivirus Japanese encephalitis (JE), which employs a licensed vaccine (yellow fever 17D) as a vector. In this vaccine, two envelope proteins (prM-E) of YF 17D virus were replaced by the corresponding genes of JE virus, with additional attenuating mutations incorporated into the JE gene inserts. Similar vaccines have been constructed by inserting prM-E genes of dengue and West Nile into YF 17D virus and are in late stage clinical studies. The dengue vaccine is, however, more complex in that it requires a mixture of four live vectors each expressing one of the four dengue serotypes. This vaccine has been evaluated in multiple clinical trials. No significant safety concerns have been found. The Phase 3 trials met their endpoints in terms of overall reduction of confirmed dengue fever, and, most importantly a significant reduction in severe dengue and hospitalization due to dengue. However, based on results that have been published so far, efficacy in preventing serotype 2 infection is less than that for the other three serotypes. In the development of these chimeric vaccines, an important series of comparative studies of safety and efficacy were made using the parental YF 17D vaccine virus as a benchmark. In this paper, we use a standardized template describing the key characteristics of the novel flavivirus vaccine vectors, in comparison to the parental YF 17D vaccine. The template facilitates scientific discourse among key stakeholders by increasing the transparency and comparability of

  16. Live virus vaccines based on a yellow fever vaccine backbone: standardized template with key considerations for a risk/benefit assessment.

    Science.gov (United States)

    Monath, Thomas P; Seligman, Stephen J; Robertson, James S; Guy, Bruno; Hayes, Edward B; Condit, Richard C; Excler, Jean Louis; Mac, Lisa Marie; Carbery, Baevin; Chen, Robert T

    2015-01-01

    The Brighton Collaboration Viral Vector Vaccines Safety Working Group (V3SWG) was formed to evaluate the safety of live, recombinant viral vaccines incorporating genes from heterologous viruses inserted into the backbone of another virus (so-called "chimeric virus vaccines"). Many viral vector vaccines are in advanced clinical trials. The first such vaccine to be approved for marketing (to date in Australia, Thailand, Malaysia, and the Philippines) is a vaccine against the flavivirus, Japanese encephalitis (JE), which employs a licensed vaccine (yellow fever 17D) as a vector. In this vaccine, two envelope proteins (prM-E) of YF 17D virus were exchanged for the corresponding genes of JE virus, with additional attenuating mutations incorporated into the JE gene inserts. Similar vaccines have been constructed by inserting prM-E genes of dengue and West Nile into YF 17D virus and are in late stage clinical studies. The dengue vaccine is, however, more complex in that it requires a mixture of four live vectors each expressing one of the four dengue serotypes. This vaccine has been evaluated in multiple clinical trials. No significant safety concerns have been found. The Phase 3 trials met their endpoints in terms of overall reduction of confirmed dengue fever, and, most importantly a significant reduction in severe dengue and hospitalization due to dengue. However, based on results that have been published so far, efficacy in preventing serotype 2 infection is less than that for the other three serotypes. In the development of these chimeric vaccines, an important series of comparative studies of safety and efficacy were made using the parental YF 17D vaccine virus as a benchmark. In this paper, we use a standardized template describing the key characteristics of the novel flavivirus vaccine vectors, in comparison to the parental YF 17D vaccine. The template facilitates scientific discourse among key stakeholders by increasing the transparency and comparability of

  17. Apple Latent Spherical Virus Vector as Vaccine for the Prevention and Treatment of Mosaic Diseases in Pea, Broad Bean, and Eustoma Plants by Bean Yellow Mosaic Virus

    Directory of Open Access Journals (Sweden)

    Nozomi Satoh

    2014-11-01

    Full Text Available We investigated the protective effects of a viral vector based on an Apple latent spherical virus (ALSV harboring a segment of the Bean yellow mosaic virus (BYMV genome against mosaic diseases in pea, broad bean, and eustoma plants caused by BYMV infection. In pea plants pre-inoculated with the ALSV vaccine and challenge inoculated with BYMV expressing green fluorescence protein, BYMV multiplication occurred in inoculated leaves, but was markedly inhibited in the upper leaves. No mosaic symptoms due to BYMV infection were observed in the challenged plants pre-inoculated with the ALSV vaccine. Simultaneous inoculation with the ALSV vaccine and BYMV also prevented mosaic symptoms in broad bean and eustoma plants, and BYMV accumulation was strongly inhibited in the upper leaves of plants treated with the ALSV vaccine. Pea and eustoma plants were pre-inoculated with BYMV followed by inoculation with the ALSV vaccine to investigate the curative effects of the ALSV vaccine. In both plant species, recovery from mosaic symptoms was observed in upper leaves and BYMV accumulation was inhibited in leaves developing post-ALSV vaccination. These results show that ALSV vaccination not only prevents mosaic diseases in pea, broad bean, and eustoma, but that it is also effective in curing these diseases.

  18. Detection and Identification of the First Viruses in Chia (Salvia hispanica

    Directory of Open Access Journals (Sweden)

    Marcos G. Celli

    2014-09-01

    Full Text Available Chia (Salvia hispanica, an herbaceous plant native to Latin America, has become important in the last 20 years due to its beneficial effects on health. Here, we present the first record and identification of two viruses in chia plants. The comparison of the complete nucleotide sequences showed the presence of two viral species with the typical genome organization of bipartite New World begomovirus, identified as Sida mosaic Bolivia virus 2 and Tomato yellow spot virus, according to the ICTV taxonomic criteria for begomovirus classification. DNA-A from Sida mosaic Bolivia virus 2 exhibited 96.1% nucleotide identity with a Bolivian isolate of Sida micrantha, and Tomato yellow spot virus showed 95.3% nucleotide identity with an Argentine bean isolate. This is the first report of begomoviruses infecting chia as well as of the occurrence of Sida mosaic Bolivia virus 2 in Argentina.

  19. Risk groups for yellow fever vaccine-associated viscerotropic disease (YEL-AVD).

    Science.gov (United States)

    Seligman, Stephen J

    2014-10-07

    Although previously considered as the safest of the live virus vaccines, reports published since 2001 indicate that live yellow fever virus vaccine can cause a severe, often fatal, multisystemic illness, yellow fever vaccine-associated viscerotropic disease (YEL-AVD), that resembles the disease it was designed to prevent. This review was prompted by the availability of a listing of the cumulative cases of YEL-AVD, insights from a statistical method for analyzing risk factors and re-evaluation of previously published data. The purpose of this review is to identify and analyze risk groups based on gender, age, outcome and predisposing illnesses. Using a passive surveillance system in the US, the incidence was reported as 0.3 to 0.4 cases per 100,000. However, other estimates range from 0 to 12 per 100,000. Identified and potential risk groups for YEL-AVD include elderly males, women between the ages of 19 and 34, people with a variety of autoimmune diseases, individuals who have been thymectomized because of thymoma, and infants and children ≤11 years old. All but the last group are supported by statistical analysis. The confirmed risk groups account for 77% (49/64) of known cases and 76% (32/42) of the deaths. The overall case fatality rate is 66% (42/64) with a rate of 80% (12/15) in young women, in contrast to 50% (13/26) in men ≥56 years old. Recognition of YEL-AVD raises the possibility that similar reactions to live chimeric flavivirus vaccines that contain a yellow fever virus vaccine backbone could occur in susceptible individuals. Delineation of risk groups focuses the search for genetic mutations resulting in immune defects associated with a given risk group. Lastly, identification of risk groups encourages concentration on measures to decrease both the incidence and the severity of YEL-AVD. Copyright © 2014 Elsevier Ltd. All rights reserved.

  20. Vaccine and Wild-Type Strains of Yellow Fever Virus Engage Distinct Entry Mechanisms and Differentially Stimulate Antiviral Immune Responses

    Directory of Open Access Journals (Sweden)

    Maria Dolores Fernandez-Garcia

    2016-02-01

    Full Text Available The live attenuated yellow fever virus (YFV vaccine 17D stands as a “gold standard” for a successful vaccine. 17D was developed empirically by passaging the wild-type Asibi strain in mouse and chicken embryo tissues. Despite its immense success, the molecular determinants for virulence attenuation and immunogenicity of the 17D vaccine are poorly understood. 17D evolved several mutations in its genome, most of which lie within the envelope (E protein. Given the major role played by the YFV E protein during virus entry, it has been hypothesized that the residues that diverge between the Asibi and 17D E proteins may be key determinants of attenuation. In this study, we define the process of YFV entry into target cells and investigate its implication in the activation of the antiviral cytokine response. We found that Asibi infects host cells exclusively via the classical clathrin-mediated endocytosis, while 17D exploits a clathrin-independent pathway for infectious entry. We demonstrate that the mutations in the 17D E protein acquired during the attenuation process are sufficient to explain the differential entry of Asibi versus 17D. Interestingly, we show that 17D binds to and infects host cells more efficiently than Asibi, which culminates in increased delivery of viral RNA into the cytosol and robust activation of the cytokine-mediated antiviral response. Overall, our study reveals that 17D vaccine and Asibi enter target cells through distinct mechanisms and highlights a link between 17D attenuation, virus entry, and immune activation.

  1. Antibody response to 17D yellow fever vaccine in Ghanaian infants.

    Science.gov (United States)

    Osei-Kwasi, M; Dunyo, S K; Koram, K A; Afari, E A; Odoom, J K; Nkrumah, F K

    2001-01-01

    To assess the seroresponses to yellow fever vaccination at 6 and 9 months of age; assess any possible adverse effects of immunization with the 17D yellow fever vaccine in infants, particularly at 6 months of age. Four hundred and twenty infants who had completed BCG, OPV and DPT immunizations were randomized to receive yellow fever immunization at either 6 or 9 months. A single dose of 0.5 ml of the reconstituted vaccine was administered to each infant by subcutaneous injection. To determine the yellow fever antibody levels of the infants, each donated 1 ml whole blood prior to immunization and 3 months post-immunization. Each serum sample was titred on Vero cells against the vaccine virus. The most common adverse reactions reported were fever, cough, diarrhoea and mild reactions at the inoculation site. The incidences of adverse reactions were not statistically different in both groups. None of the pre-immunization sera in both age groups had detectable yellow fever antibodies. Infants immunized at 6 months recorded seroconversion of 98.6% and those immunized at 9 months recorded 98% seroconversion. The GMT of their antibodies were 158.5 and 129.8, respectively. The results indicate that seroresponses to yellow fever immunization at 6 and 9 months as determined by seroconversion and GMTs of antibodies are similar. The findings of good seroresponses at 6 months without significant adverse effects would suggest that the 17D yellow fever vaccine could be recommended for use in children at 6 months in outbreak situations or in high risk endemic areas.

  2. Occurance and distribution of poty viruses infecting garlic in Pakistan

    International Nuclear Information System (INIS)

    Gilani, S.T.; Hameed, S.; Shah, H.

    2016-01-01

    The study was designed to detect and determine the prevalence, incidence and distribution of the poty viruses causing diseases in garlic (Allium sativum) from major garlic growing areas of Pakistan. The yellow stripes, mosaic and chlorotic spot symptoms of the disease resemble the viral infection in garlic reported to occur worldwide. Altogether 690 samples were collected from 29 locations of Punjab and 40 locations of Khyber Pukhtunkhwa to determine the prevalence of Onion Yellow Dwarf Virus (OYDV) and Leek Yellow Stripe Virus (LYSV). Serological testing DAS-ELISA technique was used to test the samples collected from the farmer fields. Based on the DAS-ELISA poty viruses OYDV and LYSV were detected from both provinces although the percentage incidence varied from location to location. Few areas of district Punjab were found free of LYSV but OYDV was prevalent in all locations irrespective of the varieties cultivated. Maximum disease incidence was detected in Swabi (KPK) where OYDV was 90percent and LYSV was 38 percent while in Punjab major disease incidence of OYDV (87.14 percent) and LYSV (91.44 percent) was found in Sialkot. (author)

  3. In vitro synthesis of minus-strand RNA by an isolated cereal yellow dwarf virus RNA-dependent RNA polymerase requires VPg and a stem-loop structure at the 3' end of the virus RNA.

    Science.gov (United States)

    Osman, Toba A M; Coutts, Robert H A; Buck, Kenneth W

    2006-11-01

    Cereal yellow dwarf virus (CYDV) RNA has a 5'-terminal genome-linked protein (VPg). We have expressed the VPg region of the CYDV genome in bacteria and used the purified protein (bVPg) to raise an antiserum which was able to detect free VPg in extracts of CYDV-infected oat plants. A template-dependent RNA-dependent RNA polymerase (RdRp) has been produced from a CYDV membrane-bound RNA polymerase by treatment with BAL 31 nuclease. The RdRp was template specific, being able to utilize templates from CYDV plus- and minus-strand RNAs but not those of three unrelated viruses, Red clover necrotic mosaic virus, Cucumber mosaic virus, and Tobacco mosaic virus. RNA synthesis catalyzed by the RdRp required a 3'-terminal GU sequence and the presence of bVPg. Additionally, synthesis of minus-strand RNA on a plus-strand RNA template required the presence of a putative stem-loop structure near the 3' terminus of CYDV RNA. The base-paired stem, a single-nucleotide (A) bulge in the stem, and the sequence of a tetraloop were all required for the template activity. Evidence was produced showing that minus-strand synthesis in vitro was initiated by priming by bVPg at the 3' end of the template. The data are consistent with a model in which the RdRp binds to the stem-loop structure which positions the active site to recognize the 3'-terminal GU sequence for initiation of RNA synthesis by the addition of an A residue to VPg.

  4. Comparative transcriptome profiling of a resistant vs. susceptible tomato (Solanum lycopersicum cultivar in response to infection by tomato yellow leaf curl virus.

    Directory of Open Access Journals (Sweden)

    Tianzi Chen

    Full Text Available Tomato yellow leaf curl virus (TYLCV threatens tomato production worldwide by causing leaf yellowing, leaf curling, plant stunting and flower abscission. The current understanding of the host plant defense response to this virus is very limited. Using whole transcriptome sequencing, we analyzed the differential gene expression in response to TYLCV infection in the TYLCV-resistant tomato breeding line CLN2777A (R and TYLCV-susceptible tomato breeding line TMXA48-4-0 (S. The mixed inoculated samples from 3, 5 and 7 day post inoculation (dpi were compared to non-inoculated samples at 0 dpi. Of the total of 34831 mapped transcripts, 209 and 809 genes were differentially expressed in the R and S tomato line, respectively. The proportion of up-regulated differentially expressed genes (DEGs in the R tomato line (58.37% was higher than that in the S line (9.17%. Gene ontology (GO analyses revealed that similar GO terms existed in both DEGs of R and S lines; however, some sets of defense related genes and their expression levels were not similar between the two tomato lines. Genes encoding for WRKY transcriptional factors, R genes, protein kinases and receptor (-like kinases which were identified as down-regulated DEGs in the S line were up-regulated or not differentially expressed in the R line. The up-regulated DEGs in the R tomato line revealed the defense response of tomato to TYLCV infection was characterized by the induction and regulation of a series of genes involved in cell wall reorganization, transcriptional regulation, defense response, ubiquitination, metabolite synthesis and so on. The present study provides insights into various reactions underlining the successful establishment of resistance to TYLCV in the R tomato line, and helps in the identification of important defense-related genes in tomato for TYLCV disease management.

  5. Existing and potential infection risk zones of yellow fever worldwide: a modelling analysis

    Directory of Open Access Journals (Sweden)

    Freya M Shearer, BSc

    2018-03-01

    Full Text Available Summary: Background: Yellow fever cases are under-reported and the exact distribution of the disease is unknown. An effective vaccine is available but more information is needed about which populations within risk zones should be targeted to implement interventions. Substantial outbreaks of yellow fever in Angola, Democratic Republic of the Congo, and Brazil, coupled with the global expansion of the range of its main urban vector, Aedes aegypti, suggest that yellow fever has the propensity to spread further internationally. The aim of this study was to estimate the disease's contemporary distribution and potential for spread into new areas to help inform optimal control and prevention strategies. Methods: We assembled 1155 geographical records of yellow fever virus infection in people from 1970 to 2016. We used a Poisson point process boosted regression tree model that explicitly incorporated environmental and biological explanatory covariates, vaccination coverage, and spatial variability in disease reporting rates to predict the relative risk of apparent yellow fever virus infection at a 5 × 5 km resolution across all risk zones (47 countries across the Americas and Africa. We also used the fitted model to predict the receptivity of areas outside at-risk zones to the introduction or reintroduction of yellow fever transmission. By use of previously published estimates of annual national case numbers, we used the model to map subnational variation in incidence of yellow fever across at-risk countries and to estimate the number of cases averted by vaccination worldwide. Findings: Substantial international and subnational spatial variation exists in relative risk and incidence of yellow fever as well as varied success of vaccination in reducing incidence in several high-risk regions, including Brazil, Cameroon, and Togo. Areas with the highest predicted average annual case numbers include large parts of Nigeria, the Democratic Republic of the

  6. Type III Interferon-Mediated Signaling Is Critical for Controlling Live Attenuated Yellow Fever Virus Infection In Vivo

    Directory of Open Access Journals (Sweden)

    Florian Douam

    2017-08-01

    Full Text Available Yellow fever virus (YFV is an arthropod-borne flavivirus, infecting ~200,000 people worldwide annually and causing about 30,000 deaths. The live attenuated vaccine strain, YFV-17D, has significantly contributed in controlling the global burden of yellow fever worldwide. However, the viral and host contributions to YFV-17D attenuation remain elusive. Type I interferon (IFN-α/β signaling and type II interferon (IFN-γ signaling have been shown to be mutually supportive in controlling YFV-17D infection despite distinct mechanisms of action in viral infection. However, it remains unclear how type III IFN (IFN-λ integrates into this antiviral system. Here, we report that while wild-type (WT and IFN-λ receptor knockout (λR−/− mice were largely resistant to YFV-17D, deficiency in type I IFN signaling resulted in robust infection. Although IFN-α/β receptor knockout (α/βR−/− mice survived the infection, mice with combined deficiencies in both type I signaling and type III IFN signaling were hypersusceptible to YFV-17D and succumbed to the infection. Mortality was associated with viral neuroinvasion and increased permeability of the blood-brain barrier (BBB. α/βR−/− λR−/− mice also exhibited distinct changes in the frequencies of multiple immune cell lineages, impaired T-cell activation, and severe perturbation of the proinflammatory cytokine balance. Taken together, our data highlight that type III IFN has critical immunomodulatory and neuroprotective functions that prevent viral neuroinvasion during active YFV-17D replication. Type III IFN thus likely represents a safeguard mechanism crucial for controlling YFV-17D infection and contributing to shaping vaccine immunogenicity.

  7. Identification et distribution géographique des virus responsables ...

    African Journals Online (AJOL)

    Ringspot Virus (PRSV), Watermelon Mosaic Virus (WMV) et Zucchini Yellow Mosaic Virus (ZYMV)) a été menée dans 18 parcelles de Cucumis sativus, Cucurbita maxima et Cucurbita pepo localisées à Abidjan,. Bouaké, Daloa, Korhogo, Man, San Pedro et Yamoussoukro. Les tests sérologiques DAS-ELISA réalisés sur.

  8. "Mancha-cafe" em soja: seleção para resistência e interação entre genótipos e épocas de inoculação Seedcoat mottling in soybeans: selection for resistance and interaction between genotypes and inoculation date

    Directory of Open Access Journals (Sweden)

    André Luiz Lourençao

    1996-01-01

    infectadas no estádio vegetativo. Esses resultados fortalecem a diretriz utilizada no programa de melhoramento da Seção de Leguminosas do IAC: a de eliminar plantas e/ou linhagens com incidência de "mancha-café".The soybean mosaic virus (SMV is widespread in all soybean production areas. The mottled brown seed is the most characteristic symptom under our conditions, so in Brazil the disease was called "mancha-café" (coffee-spot. The mottling was the main limiting factor to the seed production in the certification system. The present paper had two objetives: screenning lines with different levels of mottled seeds, and to verify the interaction between selected genotypes and inoculation dates. During 1987, 131 F4:5 experimental lines from the cross IAC78-2318 x Santa Rosa, both susceptible to SMV, were evaluated under field conditions in Campinas (SP, Brazil. In the next year, seventeen selected lines plus the cultivars Santa Rosa, representing the five levels of mottling were planted again under field conditions in randomized complete-block design, with six replications. The results showed that the screenning realized in the field was efficient to identify the lines with different levels of mottled seeds. It was also observed that this characteristic was not much influenced by environmental effects as indicated by the positive and high correlation between diseases notes of both years, as well as the low value of the coefficient of variation. An additional study was carried out under greenhouse conditions to evaluate genotypes in distinct growth stages when mechanically inoculated with the virus. It consisted of a factorial experiment, involving a non-inoculated control, three inoculation times, and five lines representing notes from 1 to 5, plus the cultivars Santa Rosa, IAC-Santa Rosa PC and IAC-Santa Rosa DF. The genotypes were sowed in plastic bags and at the maturity, the following evaluations were made: the mottled seed rate, seed production (g/3 plants, mass (g of

  9. Spawning Characteristics and Artificial Hatching of Female Mottled Skate, Beringraja pulchra in the West Coast of Korea.

    Science.gov (United States)

    Kang, Hee-Woong; Jo, Yeong-Rok; Kang, Duk-Yong; Jeong, Gyeong-Suk; Jo, Hyun-Su

    2013-09-01

    The gonadsomatic index (GSI) of mottled skate was the highest in April, GSI and HSI showed a reverse phase for its reproductive cycle. The fish had one pair of egg capsules, having 1 to 7 fertilized eggs, and spawned all the year round. When surveying the reproductive characteristics of females over 63 ㎝ in disc width, we found the spawning peak was between April to June, and the appearance ratio of egg capsules was the highest in May (32.1%). The eggs were hatched at 8°C, 13°C, 18°C, water temperature (12.8 to 24.2°C), and the best hatching temperature was 18°C. The number of fish hatched was 4 to 5 fish/egg capsules, and the hatching rate was 100%. The sex ratios of hatching larvae were 45.5% female and 54.5% male. Therefore this study will provide fundamental data and information for artificial reproduction of the mottled skate.

  10. Correlation between particle multiplicity and location on virion RNA of the assembly initiation site for viruses of the tobacco mosaic virus group.

    Science.gov (United States)

    Fukuda, M; Meshi, T; Okada, Y; Otsuki, Y; Takebe, I

    1981-07-01

    The initiation site for reconstitution on genome RNA was determined by electron microscopic serology for a watermelon strain of cucumber green mottle mosaic virus (CGMMV-W), which is chemically and serologically related to tobacco mosaic virus (TMV). The initiation site was located at the same position as that of the cowpea strain, a virus that produces short rods of encapsidated subgenomic messenger RNA for the coat protein (a two-component TMV), being about 320 nucleotides away from the 3' terminus, and hence within the coat protein cistron. Although CGMMV-W was until now believed to be a single-component TMV, the location of the initiation site indicated the presence of short rods containing coat protein messenger RNA in CGMMV-W-infected tissue, as in the case for the cowpea strain. We found such short rods in CGMMV-W-infected tissue. The results confirmed our previous hypothesis that the site of the initiation region for reconstitution determines the rod multiplicity of TMV. The finding of the second two-component TMV, CGMMV, indicates that the cowpea strain of TMV is not unique in being a two-component virus and that the location of the assembly initiation site on the genome RNA can be a criterion for grouping of viruses.

  11. Pre-clinical efficacy and safety of experimental vaccines based on non-replicating vaccinia vectors against yellow fever.

    Directory of Open Access Journals (Sweden)

    Birgit Schäfer

    Full Text Available BACKGROUND: Currently existing yellow fever (YF vaccines are based on the live attenuated yellow fever virus 17D strain (YFV-17D. Although, a good safety profile was historically attributed to the 17D vaccine, serious adverse events have been reported, making the development of a safer, more modern vaccine desirable. METHODOLOGY/PRINCIPAL FINDINGS: A gene encoding the precursor of the membrane and envelope (prME protein of the YFV-17D strain was inserted into the non-replicating modified vaccinia virus Ankara and into the D4R-defective vaccinia virus. Candidate vaccines based on the recombinant vaccinia viruses were assessed for immunogenicity and protection in a mouse model and compared to the commercial YFV-17D vaccine. The recombinant live vaccines induced γ-interferon-secreting CD4- and functionally active CD8-T cells, and conferred full protection against lethal challenge already after a single low immunization dose of 10(5 TCID(50. Surprisingly, pre-existing immunity against wild-type vaccinia virus did not negatively influence protection. Unlike the classical 17D vaccine, the vaccinia virus-based vaccines did not cause mortality following intracerebral administration in mice, demonstrating better safety profiles. CONCLUSIONS/SIGNIFICANCE: The non-replicating recombinant YF candidate live vaccines induced a broad immune response after single dose administration, were effective even in the presence of a pre-existing immunity against vaccinia virus and demonstrated an excellent safety profile in mice.

  12. Pre-Clinical Efficacy and Safety of Experimental Vaccines Based on Non-Replicating Vaccinia Vectors against Yellow Fever

    Science.gov (United States)

    Schäfer, Birgit; Holzer, Georg W.; Joachimsthaler, Alexandra; Coulibaly, Sogue; Schwendinger, Michael; Crowe, Brian A.; Kreil, Thomas R.; Barrett, P. Noel; Falkner, Falko G.

    2011-01-01

    Background Currently existing yellow fever (YF) vaccines are based on the live attenuated yellow fever virus 17D strain (YFV-17D). Although, a good safety profile was historically attributed to the 17D vaccine, serious adverse events have been reported, making the development of a safer, more modern vaccine desirable. Methodology/Principal Findings A gene encoding the precursor of the membrane and envelope (prME) protein of the YFV-17D strain was inserted into the non-replicating modified vaccinia virus Ankara and into the D4R-defective vaccinia virus. Candidate vaccines based on the recombinant vaccinia viruses were assessed for immunogenicity and protection in a mouse model and compared to the commercial YFV-17D vaccine. The recombinant live vaccines induced γ-interferon-secreting CD4- and functionally active CD8-T cells, and conferred full protection against lethal challenge already after a single low immunization dose of 105 TCID50. Surprisingly, pre-existing immunity against wild-type vaccinia virus did not negatively influence protection. Unlike the classical 17D vaccine, the vaccinia virus-based vaccines did not cause mortality following intracerebral administration in mice, demonstrating better safety profiles. Conclusions/Significance The non-replicating recombinant YF candidate live vaccines induced a broad immune response after single dose administration, were effective even in the presence of a pre-existing immunity against vaccinia virus and demonstrated an excellent safety profile in mice. PMID:21931732

  13. An integrated protein localization and interaction map for Potato yellow dwarf virus, type species of the genus Nucleorhabdovirus

    International Nuclear Information System (INIS)

    Bandyopadhyay, Anindya; Kopperud, Kristin; Anderson, Gavin; Martin, Kathleen; Goodin, Michael

    2010-01-01

    The genome of Potato yellow dwarf virus (PYDV; Nucleorhabdovirus type species) was determined to be 12,875 nucleotides (nt). The antigenome is organized into seven open reading frames (ORFs) ordered 3'-N-X-P-Y-M-G-L-5', which likely encode the nucleocapsid, phospho, movement, matrix, glyco and RNA-dependent RNA polymerase proteins, respectively, except for X, which is of unknown function. The ORFs are flanked by a 3' leader RNA of 149 nt and a 5' trailer RNA of 97 nt, and are separated by conserved intergenic junctions. Phylogenetic analyses indicated that PYDV is closely related to other leafhopper-transmitted rhabdoviruses. Functional protein assays were used to determine the subcellular localization of PYDV proteins. Surprisingly, the M protein was able to induce the intranuclear accumulation of the inner nuclear membrane in the absence of any other viral protein. Finally, bimolecular fluorescence complementation was used to generate the most comprehensive protein interaction map for a plant-adapted rhabdovirus to date.

  14. Characterization of Yellow Fever Virus Infection of Human and Non-human Primate Antigen Presenting Cells and Their Interaction with CD4+ T Cells.

    Directory of Open Access Journals (Sweden)

    Yu Cong

    2016-05-01

    Full Text Available Humans infected with yellow fever virus (YFV, a mosquito-borne flavivirus, can develop illness ranging from a mild febrile disease to hemorrhagic fever and death. The 17D vaccine strain of YFV was developed in the 1930s, has been used continuously since development and has proven very effective. Genetic differences between vaccine and wild-type viruses are few, yet viral or host mechanisms associated with protection or disease are not fully understood. Over the past 20 years, a number of cases of vaccine-associated disease have been identified following vaccination with 17D; these cases have been correlated with reduced immune status at the time of vaccination. Recently, several studies have evaluated T cell responses to vaccination in both humans and non-human primates, but none have evaluated the response to wild-type virus infection. In the studies described here, monocyte-derived macrophages (MDM and dendritic cells (MoDC from both humans and rhesus macaques were evaluated for their ability to support infection with either wild-type Asibi virus or the 17D vaccine strain and the host cytokine and chemokine response characterized. Human MoDC and MDM were also evaluated for their ability to stimulate CD4+ T cells. It was found that MoDC and MDM supported viral replication and that there were differential cytokine responses to infection with either wild-type or vaccine viruses. Additionally, MoDCs infected with live 17D virus were able to stimulate IFN-γ and IL-2 production in CD4+ T cells, while cells infected with Asibi virus were not. These data demonstrate that wild-type and vaccine YFV stimulate different responses in target antigen presenting cells and that wild-type YFV can inhibit MoDC activation of CD4+ T cells, a critical component in development of protective immunity. These data provide initial, but critical insight into regulatory capabilities of wild-type YFV in development of disease.

  15. Presence and Distribution of Oilseed Pumpkin Viruses and Molecular Detection of Zucchini Yellow Mosaic Virus

    OpenAIRE

    Ana Vučurović; Aleksandra Bulajić; Ivana Đekić; Danijela Ristić; Janoš Berenji; Branka Krstić

    2009-01-01

    Over the past decade, intensive spread of virus infections of oilseed pumpkin has resulted in significant economic losses in pumpkin crop production, which is currently expanding in our country. In 2007 and 2008, a survey for the presence and distribution of oilseed pumpkin viruses was carried out in order to identify viruses responsible for epidemics and incidences of very destructive symptoms on cucurbit leaves and fruits. Monitoring and collecting samples of oil pumpkin, as well as other s...

  16. Crystallization of mutants of Turnip yellow mosaic virus protease/ubiquitin hydrolase designed to prevent protease self-recognition.

    Science.gov (United States)

    Ayach, Maya; Bressanelli, Stéphane

    2015-04-01

    Processing of the polyprotein of Turnip yellow mosaic virus is mediated by the protease PRO. PRO cleaves at two places, one of which is at the C-terminus of the PRO domain of another polyprotein molecule. In addition to this processing activity, PRO possesses an ubiquitin hydrolase (DUB) activity. The crystal structure of PRO has previously been reported in its polyprotein-processing mode with the C-terminus of one PRO inserted into the catalytic site of the next PRO, generating PRO polymers in the crystal packing of the trigonal space group. Here, two mutants designed to disrupt specific PRO-PRO interactions were generated, produced and purified. Crystalline plates were obtained by seeding and cross-seeding from initial `sea urchin'-like microcrystals of one mutant. The plates diffracted to beyond 2 Å resolution at a synchrotron source and complete data sets were collected for the two mutants. Data processing and analysis indicated that both mutant crystals belonged to the same monoclinic space group, with two molecules of PRO in the asymmetric unit.

  17. Existing and potential infection risk zones of yellow fever worldwide: a modelling analysis.

    Science.gov (United States)

    Shearer, Freya M; Longbottom, Joshua; Browne, Annie J; Pigott, David M; Brady, Oliver J; Kraemer, Moritz U G; Marinho, Fatima; Yactayo, Sergio; de Araújo, Valdelaine E M; da Nóbrega, Aglaêr A; Fullman, Nancy; Ray, Sarah E; Mosser, Jonathan F; Stanaway, Jeffrey D; Lim, Stephen S; Reiner, Robert C; Moyes, Catherine L; Hay, Simon I; Golding, Nick

    2018-03-01

    Yellow fever cases are under-reported and the exact distribution of the disease is unknown. An effective vaccine is available but more information is needed about which populations within risk zones should be targeted to implement interventions. Substantial outbreaks of yellow fever in Angola, Democratic Republic of the Congo, and Brazil, coupled with the global expansion of the range of its main urban vector, Aedes aegypti, suggest that yellow fever has the propensity to spread further internationally. The aim of this study was to estimate the disease's contemporary distribution and potential for spread into new areas to help inform optimal control and prevention strategies. We assembled 1155 geographical records of yellow fever virus infection in people from 1970 to 2016. We used a Poisson point process boosted regression tree model that explicitly incorporated environmental and biological explanatory covariates, vaccination coverage, and spatial variability in disease reporting rates to predict the relative risk of apparent yellow fever virus infection at a 5 × 5 km resolution across all risk zones (47 countries across the Americas and Africa). We also used the fitted model to predict the receptivity of areas outside at-risk zones to the introduction or reintroduction of yellow fever transmission. By use of previously published estimates of annual national case numbers, we used the model to map subnational variation in incidence of yellow fever across at-risk countries and to estimate the number of cases averted by vaccination worldwide. Substantial international and subnational spatial variation exists in relative risk and incidence of yellow fever as well as varied success of vaccination in reducing incidence in several high-risk regions, including Brazil, Cameroon, and Togo. Areas with the highest predicted average annual case numbers include large parts of Nigeria, the Democratic Republic of the Congo, and South Sudan, where vaccination coverage in 2016

  18. Autophagy induction in tobacco leaves infected by potato virus Y{sup O} and its putative roles

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Dabin; Park, Jaeyoung [Department of Life Science & BK21-Plus Research Team for Bioactive Control Technology, Chosun University, 309 Pilmundaero, Dong-gu, Gwangju 501-759 (Korea, Republic of); Oh, Seonhee, E-mail: seonh@chosun.ac.kr [Department of Premedics, School of Medicine, Chosun University, 309 Pilmundaero, Dong-gu, Gwangju 501-759 (Korea, Republic of); Cheong, Hyunsook, E-mail: hscheong@chosun.ac.kr [Department of Life Science & BK21-Plus Research Team for Bioactive Control Technology, Chosun University, 309 Pilmundaero, Dong-gu, Gwangju 501-759 (Korea, Republic of)

    2016-06-03

    Autophagy plays a critical role in the innate immune response of plants to pathogen infection. In the present study, we examined autophagy induced by potato virus Y ordinary strain (PVY{sup O}) infection in tobacco (Nicotiana benthamiana). Enzyme-linked immunosorbent assays revealed that the number of virus particles in the plant peaked at 2 weeks post-inoculation and then gradually decreased. Additionally, the amount of virus increased significantly in the 3rd and 4th leaves distal to the inoculated leaf and decreased slightly in the 5th leaf. Within 2 weeks of PVY{sup O} inoculation, the tobacco leaves showed typical symptoms of Potyvirus inoculation, including mottling, yellowing, a mosaic pattern, and necrotic tissue changes at the inoculated site. Based on an ultrastructural analysis of the PVY{sup O}-infected tobacco leaves, virus aggregates appeared as longitudinal and transverse arrays and pinwheels, which are typical of Potyvirus inoculation. Moreover, PVY{sup O} infection caused changes in the number, size, and shape of chloroplasts, whereas the number of plastogranules increased markedly. Furthermore, double-membrane autophagosome-like vacuoles, including electron-dense materials, laminated structures, and cellular organelles, were found. The induction of autophagy after the PVY{sup O} infection of tobacco leaves was further confirmed by the expression of lipidated microtubule-associated protein 1 light chain 3 (LC3)-II, an autophagy marker and p62, an autophagy adaptor protein. The LC3-II levels increased daily over the 4-week period. Although virus inoculation was performed systemically on the basal leaves of the plants, LC3-II was expressed throughout the leaves and the expression was higher in leaves distal to the inoculated leaf. Moreover, PVY{sup O} infection caused the activation of stress-activated protein kinases/c-Jun N-terminal kinases. Therefore, PVY{sup O} infection-induced autophagy was positively correlated with the virus content

  19. Phylogenetic analysis and inflow route of Tomato yellow leaf curl virus (TYLCV) and Bemisia tabaci in Korea.

    Science.gov (United States)

    Lee, Hyejung; Song, Woogeun; Kwak, Hae-Ryun; Kim, Jae-Deok; Park, Jungan; Auh, Chung-Kyoon; Kim, Dae-Hyun; Lee, Kyeong-Yeoll; Lee, Sukchan; Choi, Hong-Soo

    2010-11-01

    Tomato yellow leaf curl virus (TYLCV) is a member of the genus Begomovirus of the family Geminiviridae, members of which are characterized by closed circular single-stranded DNA genomes of 2.7-2.8 kb in length, and include viruses transmitted by the Bemisia tabaci whitefly. No reports of TYLCV in Korea are available prior to 2008, after which TYLCV spread rapidly to most regions of the southern Korean peninsula (Gyeongsang-Do, Jeolla-Do and Jeju-Do). Fifty full sequences of TYLCV were analyzed in this study, and the AC1, AV1, IR, and full sequences were analyzed via the muscle program and bayesian analysis. Phylogenetic analysis demonstrated that the Korea TYLCVs were divided into two subgroups. The TYLCV Korea 1 group (Masan) originated from TYLCV Japan (Miyazaki) and the TYLCV Korea 2 group (Jeju/Jeonju) from TYLCV Japan (Tosa/Haruno). A B. tabaci phylogenetic tree was constructed with 16S rRNA and mitochondria cytochrome oxidase I (MtCOI) sequences using the muscle program and MEGA 4.0 in the neighbor-joining algorithm. The sequence data of 16S rRNA revealed that Korea B. tabaci was closely aligned to B. tabaci isolated in Iran and Nigeria. The Q type of B. tabaci, which was originally identified as a viruliferous insect in 2008, was initially isolated in Korea as a non-viruliferous insect in 2005. Therefore, we suggest that two TYLCV Japan isolates were introduced to Korea via different routes, and then transmitted by native B. tabaci.

  20. Preliminary X-ray Data Analysis of Crystalline Hibiscus Chlorotic Ringspot Virus

    Energy Technology Data Exchange (ETDEWEB)

    Cheng, A.; Speir, J; Yuan, Y; Johnson, J; Wong, S

    2009-01-01

    Hibiscus chlorotic ringspot virus (HCRSV) is a positive-sense monopartite single-stranded RNA virus that belongs to the Carmovirus genus of the Tombusviridae family, which includes carnation mottle virus (CarMV). The HCRSV virion has a 30 nm diameter icosahedral capsid with T = 3 quasi-symmetry containing 180 copies of a 38 kDa coat protein (CP) and encapsidates a full-length 3.9 kb genomic RNA. Authentic virus was harvested from infected host kenaf leaves and was purified by saturated ammonium sulfate precipitation, sucrose density-gradient centrifugation and anion-exchange chromatography. Virus crystals were grown in multiple conditions; one of the crystals diffracted to 3Synchrotron .2 A resolution and allowed the collection of a partial data set. The crystal belonged to space group R32, with unit-cell parameters a = b = 336.4, c = 798.5 . Packing considerations and rotation-function analysis determined that there were three particles per unit cell, all of which have the same orientation and fixed positions, and resulted in tenfold noncrystallography symmetry for real-space averaging. The crystals used for the structure determination of southern bean mosaic virus (SBMV) have nearly identical characteristics. Together, these findings will greatly aid the high-resolution structure determination of HCRSV.

  1. The typical RB76 recombination breakpoint of the invasive recombinant tomato yellow leaf curl virus of Morocco can be generated experimentally but is not positively selected in tomato.

    Science.gov (United States)

    Belabess, Z; Urbino, C; Granier, M; Tahiri, A; Blenzar, A; Peterschmitt, M

    2018-01-02

    TYLCV-IS76 is an unusual recombinant between the highly recombinogenic tomato yellow leaf curl virus (TYLCV) and tomato yellow leaf curl Sardinia virus (TYLCSV), two Mediterranean begomoviruses (Geminiviridae). In contrast with the previously reported TYLCV/TYLCSV recombinants, it has a TYLCSV derived fragment of only 76 nucleotides, and has replaced its parental viruses in natural conditions (Morocco, Souss region). The viral population shift coincided with the deployment of the popular Ty-1 resistant tomato cultivars, and according to experimental studies, has been driven by a strong positive selection in such resistant plants. However, although Ty-1 cultivars were extensively used in Mediterranean countries, TYLCV-IS76 was not reported outside Morocco. This, in combination with its unusual recombination pattern suggests that it was generated through a rare and possibly multistep process. The potential generation of a recombination breakpoint (RB) at locus 76 (RB76) was investigated over time in 10 Ty-1 resistant and 10 nearly isogenic susceptible tomato plants co-inoculated with TYLCV and TYLCSV clones. RB76 could not be detected in the recombinant progeny using the standard PCR/sequencing approach that was previously designed to monitor the emergence of TYLCV-IS76 in Morocco. Using a more sensitive PCR test, RB76 was detected in one resistant and five susceptible plants. The results are consistent with a very low intra-plant frequency of RB76 bearing recombinants throughout the test and support the hypothesis of a rare emergence of TYLCV-IS76. More generally, RBs were more scattered in resistant than in susceptible plants and an unusual RB at position 141 (RB141) was positively selected in the resistant cultivar; interestingly, RB141 bearing recombinants were detected in resistant tomato plants from the field. Scenarios of TYLCV-IS76 pre-emergence are proposed. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. Epidemiology and integrated management of persistently transmitted aphid-borne viruses of legume and cereal crops in West Asia and North Africa.

    Science.gov (United States)

    Makkouk, Khaled M; Kumari, Safaa G

    2009-05-01

    Cool-season food legumes (faba bean, lentil, chickpea and pea) and cereals (bread and durum wheat and barley) are the most important and widely cultivated crops in West Asia and North Africa (WANA), where they are the main source of carbohydrates and protein for the majority of the population. Persistently transmitted aphid-borne viruses pose a significant limitation to legume and cereal production worldwide. Surveys conducted in many countries in WANA during the last three decades established that the most important of these viruses are: Faba bean necrotic yellows virus (FBNYV: genus Nanovirus; family Nanoviridae), Bean leafroll virus (BLRV: genus Luteovirus; family Luteoviridae), Beet western yellows virus (BWYV: genus Polerovirus; family Luteoviridae), Soybean dwarf virus (SbDV: genus Luteovirus; family Luteoviridae) and Chickpea chlorotic stunt virus (CpCSV: genus Polerovirus; family Luteoviridae) which affect legume crops, and Barley yellow dwarf virus-PAV (BYDV-PAV: genus Luteovirus; family Luteoviridae), Barley yellow dwarf virus-MAV (BYDV-MAV: genus Luteovirus; family Luteoviridae) and Cereal yellow dwarf virus-RPV (CYDV-RPV: genus Polerovirus; family Luteoviridae) which affect cereal crops. Loss in yield caused by these viruses is usually high when infection occurs early in the growing season. Many aphid vector species for the above-mentioned viruses are reported to be prevalent in the WANA region. In addition, in this region many wild species (annual or perennial) were found infected with these viruses and may play an important role in their ecology and spread. Fast spread of these diseases was always associated with high aphid vector populations and activity. Although virus disease management can be achieved by combining several control measures, development of resistant genotypes is undoubtedly one of the most appropriate control methods. Over the last three decades barley and wheat genotypes resistant to BYDV, faba bean genotypes resistant to BLRV, and

  3. Mottled Neuherberg (Mo sup(N)), a new male-lethal coat colour mutation of the house mouse (Mus musculus)

    International Nuclear Information System (INIS)

    Schroeder, J.H.

    1975-01-01

    A new semidominant X-chromosomal mutation, Mottled Neuherberg (Mo sup(N)), which causes coat colour variegation is described. Mo sup(N) arose in the second postirradiation generation after 2 x 200 R of X-rays (24 hours apart) to oocytes of X/O mice. Heterozygous Mo sup(N) females have irregular patches of fully and lightly coloured fur over the whole coat with curly vibrissae. Their viability is reduced, about 3% of the heterozygotes dying prenatally and 6 to 28% dying postnatally before weaning. Survivors are fertile without externally visible abnormalities. Hemizygous Mo sup(N) males die in utero after implantation. The recombination frequency between Mo sup(N) and tabby (Ta) was 3.65 +- 3.16% (with 95% -confidence limits). Therefore, it is suggested that Mo sup(N) is a new allele of the mottled (Mo) locus of the house mouse. Mo sup(N)-bearing ova seem to have a lower chance of becoming fertilized by wild-type spermatozoa than by Ta-bearing spermatozoa. (orig.) [de

  4. Transmission of Turnip yellows virus by Myzus persicae Is Reduced by Feeding Aphids on Double-Stranded RNA Targeting the Ephrin Receptor Protein

    Directory of Open Access Journals (Sweden)

    Michaël Mulot

    2018-03-01

    Full Text Available Aphid-transmitted plant viruses are a threat for major crops causing massive economic loss worldwide. Members in the Luteoviridae family are transmitted by aphids in a circulative and non-replicative mode. Virions are acquired by aphids when ingesting sap from infected plants and are transported through the gut and the accessory salivary gland (ASG cells by a transcytosis mechanism relying on virus-specific receptors largely unknown. Once released into the salivary canal, virions are inoculated to plants, together with saliva, during a subsequent feeding. In this paper, we bring in vivo evidence that the membrane-bound Ephrin receptor (Eph is a novel aphid protein involved in the transmission of the Turnip yellows virus (TuYV, Polerovirus genus, Luteoviridae family by Myzus persicae. The minor capsid protein of TuYV, essential for aphid transmission, was able to bind the external domain of Eph in yeast. Feeding M. persicae on in planta- or in vitro-synthesized dsRNA targeting Eph-mRNA (dsRNAEph did not affect aphid feeding behavior but reduced accumulation of TuYV genomes in the aphid's body. Consequently, TuYV transmission efficiency by the dsRNAEph-treated aphids was reproducibly inhibited and we brought evidence that Eph is likely involved in intestinal uptake of the virion. The inhibition of virus uptake after dsRNAEph acquisition was also observed for two other poleroviruses transmitted by M. persicae, suggesting a broader role of Eph in polerovirus transmission. Finally, dsRNAEph acquisition by aphids did not affect nymph production. These results pave the way toward an ecologically safe alternative of insecticide treatments that are used to lower aphid populations and reduce polerovirus damages.

  5. Transmission of Turnip yellows virus by Myzus persicae Is Reduced by Feeding Aphids on Double-Stranded RNA Targeting the Ephrin Receptor Protein.

    Science.gov (United States)

    Mulot, Michaël; Monsion, Baptiste; Boissinot, Sylvaine; Rastegar, Maryam; Meyer, Sophie; Bochet, Nicole; Brault, Véronique

    2018-01-01

    Aphid-transmitted plant viruses are a threat for major crops causing massive economic loss worldwide. Members in the Luteoviridae family are transmitted by aphids in a circulative and non-replicative mode. Virions are acquired by aphids when ingesting sap from infected plants and are transported through the gut and the accessory salivary gland (ASG) cells by a transcytosis mechanism relying on virus-specific receptors largely unknown. Once released into the salivary canal, virions are inoculated to plants, together with saliva, during a subsequent feeding. In this paper, we bring in vivo evidence that the membrane-bound Ephrin receptor (Eph) is a novel aphid protein involved in the transmission of the Turnip yellows virus (TuYV, Polerovirus genus, Luteoviridae family) by Myzus persicae . The minor capsid protein of TuYV, essential for aphid transmission, was able to bind the external domain of Eph in yeast. Feeding M. persicae on in planta - or in vitro -synthesized dsRNA targeting Eph -mRNA (dsRNA Eph ) did not affect aphid feeding behavior but reduced accumulation of TuYV genomes in the aphid's body. Consequently, TuYV transmission efficiency by the dsRNA Eph -treated aphids was reproducibly inhibited and we brought evidence that Eph is likely involved in intestinal uptake of the virion. The inhibition of virus uptake after dsRNA Eph acquisition was also observed for two other poleroviruses transmitted by M. persicae , suggesting a broader role of Eph in polerovirus transmission. Finally, dsRNA Eph acquisition by aphids did not affect nymph production. These results pave the way toward an ecologically safe alternative of insecticide treatments that are used to lower aphid populations and reduce polerovirus damages.

  6. Complete nucleotide sequences of a new bipartite begomovirus from Malvastrum sp. plants with bright yellow mosaic symptoms in South Texas.

    Science.gov (United States)

    Alabi, Olufemi J; Villegas, Cecilia; Gregg, Lori; Murray, K Daniel

    2016-06-01

    Two isolates of a novel bipartite begomovirus, tentatively named malvastrum bright yellow mosaic virus (MaBYMV), were molecularly characterized from naturally infected plants of the genus Malvastrum showing bright yellow mosaic disease symptoms in South Texas. Six complete DNA-A and five DNA-B genome sequences of MaBYMV obtained from the isolates ranged in length from 2,608 to 2,609 nucleotides (nt) and 2,578 to 2,605 nt, respectively. Both genome segments shared a 178- to 180-nt common region. In pairwise comparisons, the complete DNA-A and DNA-B sequences of MaBYMV were most similar (87-88 % and 79-81 % identity, respectively) and phylogenetically related to the corresponding sequences of sida mosaic Sinaloa virus-[MX-Gua-06]. Further analysis revealed that MaBYMV is a putative recombinant virus, thus supporting the notion that malvaceous hosts may be influencing the evolution of several begomoviruses. The design of new diagnostic primers enabled the detection of MaBYMV in cohorts of Bemisia tabaci collected from symptomatic Malvastrum sp. plants, thus implicating whiteflies as potential vectors of the virus.

  7. Reemergence of yellow fever: detection of transmission in the State of São Paulo, Brazil, 2008

    Directory of Open Access Journals (Sweden)

    Eduardo Stramandinoli Moreno

    2011-06-01

    Full Text Available INTRODUCTION: Following yellow fever virus (YFV isolation in monkeys from the São José do Rio Preto region and two fatal human autochthonous cases from the Ribeirão Preto region, State of São Paulo, Brazil, two expeditions for entomological research and eco-epidemiological evaluation were conducted. METHODS: A total of 577 samples from humans, 108 from monkeys and 3,049 mosquitoes were analyzed by one or more methods: virus isolation, ELISA-IgM, RT-PCR, histopathology and immunohistochemical. RESULTS: Of the 577 human samples, 531 were tested by ELISA-IgM, with 3 positives, and 235 were inoculated into mice and 199 in cell culture, resulting in one virus isolation. One sample was positive by histopathology and immunohistochemical. Using RT-PCR, 25 samples were processed with 4 positive reactions. A total of 108 specimens of monkeys were examined, 108 were inoculated into mice and 45 in cell culture. Four virus strains were isolated from Alouattacaraya. A total of 931 mosquitoes were captured in Sao Jose do Rio Preto and 2,118 in Ribeirão Preto and separated into batches. A single isolation of YFV was derived from a batch of 9 mosquitoes Psorophoraferox, collected in Urupês, Ribeirão Preto region. A serological survey was conducted with 128 samples from the municipalities of São Carlos, Rincão and Ribeirão Preto and 10 samples from contacts of patients from Ribeirão Preto. All samples were negative by ELISA-IgM for YFV. CONCLUSIONS: The results confirm the circulation of yellow fever, even though sporadic, in the Sao Paulo State and reinforce the importance of vaccination against yellow fever in areas considered at risk.

  8. Pre-infestation of Tomato Plants by Aphids Modulates Transmission-Acquisition Relationship among Whiteflies, Tomato Yellow Leaf Curl Virus (TYLCV and Plants

    Directory of Open Access Journals (Sweden)

    Xiao L. Tan

    2017-09-01

    Full Text Available Herbivory defense systems in plants are largely regulated by jasmonate-(JA and salicylate-(SA signaling pathways. Such defense mechanisms may impact insect feeding dynamic, may also affect the transmission-acquisition relationship among virus, plants and vectoring insects. In the context of the tomato – whitefly – Tomato Yellow Leaf Curl Virus (TYLCV biological model, we tested the impact of pre-infesting plants with a non-vector insect (aphid Myzus persicae on feeding dynamics of a vector insect (whitefly Bemisia tabaci as well as virus transmission-acquisition. We showed that an aphid herbivory period of 0–48 h led to a transient systemic increase of virus concentration in the host plant (root, stem, and leaf, with the same pattern observed in whiteflies feeding on aphid-infested plants. We used real-time quantitative PCR to study the expression of key genes of the SA- and JA-signaling pathways, as well as electrical penetration graph (EPG to characterize the impact of aphid pre-infestation on whitefly feeding during TYLCV transmission (whitefly to tomato and acquisition (tomato to whitefly. The impact of the duration of aphid pre-infestation (0, 24, or 48 h on phloem feeding by whitefly (E2 during the transmission phase was similar to that of global whitefly feeding behavior (E1, E2 and probing duration during the acquisition phase. In addition, we observed that a longer phase of aphid pre-infestation prior to virus transmission by whitefly led to the up-regulation and down-regulation of SA- and JA-signaling pathway genes, respectively. These results demonstrated a significant impact of aphid pre-infestation on the tomato – whitefly – TYLCV system. Transmission and acquisition of TYLCV was positively correlated with feeding activity of B. tabaci, and both were mediated by the SA- and JA-pathways. TYLCV concentration during the transmission phases was modulated by up- and down-regulation of SA- and JA-pathways, respectively. The two

  9. Type III Interferon-Mediated Signaling Is Critical for Controlling Live Attenuated Yellow Fever Virus Infection In Vivo.

    Science.gov (United States)

    Douam, Florian; Soto Albrecht, Yentli E; Hrebikova, Gabriela; Sadimin, Evita; Davidson, Christian; Kotenko, Sergei V; Ploss, Alexander

    2017-08-15

    Yellow fever virus (YFV) is an arthropod-borne flavivirus, infecting ~200,000 people worldwide annually and causing about 30,000 deaths. The live attenuated vaccine strain, YFV-17D, has significantly contributed in controlling the global burden of yellow fever worldwide. However, the viral and host contributions to YFV-17D attenuation remain elusive. Type I interferon (IFN-α/β) signaling and type II interferon (IFN-γ) signaling have been shown to be mutually supportive in controlling YFV-17D infection despite distinct mechanisms of action in viral infection. However, it remains unclear how type III IFN (IFN-λ) integrates into this antiviral system. Here, we report that while wild-type (WT) and IFN-λ receptor knockout (λR -/- ) mice were largely resistant to YFV-17D, deficiency in type I IFN signaling resulted in robust infection. Although IFN-α/β receptor knockout (α/βR -/- ) mice survived the infection, mice with combined deficiencies in both type I signaling and type III IFN signaling were hypersusceptible to YFV-17D and succumbed to the infection. Mortality was associated with viral neuroinvasion and increased permeability of the blood-brain barrier (BBB). α/βR -/- λR -/- mice also exhibited distinct changes in the frequencies of multiple immune cell lineages, impaired T-cell activation, and severe perturbation of the proinflammatory cytokine balance. Taken together, our data highlight that type III IFN has critical immunomodulatory and neuroprotective functions that prevent viral neuroinvasion during active YFV-17D replication. Type III IFN thus likely represents a safeguard mechanism crucial for controlling YFV-17D infection and contributing to shaping vaccine immunogenicity. IMPORTANCE YFV-17D is a live attenuated flavivirus vaccine strain recognized as one of the most effective vaccines ever developed. However, the host and viral determinants governing YFV-17D attenuation and its potent immunogenicity are still unknown. Here, we analyzed the

  10. Occurrence of Potato virus X on hybrid dock in Czech Republic

    Czech Academy of Sciences Publication Activity Database

    Petrzik, Karel

    2009-01-01

    Roč. 53, č. 1 (2009), s. 49-52 ISSN 0001-723X R&D Projects: GA AV ČR(CZ) 1QS500510558 Institutional research plan: CEZ:AV0Z50510513 Keywords : hybrid dock * potato virus X * Radish mosaic virus * Turnip yellow mosaic virus Subject RIV: EE - Microbiology, Virology Impact factor: 0.746, year: 2009

  11. Reaction of sweet pepper to the potato virus y (PVYm

    Directory of Open Access Journals (Sweden)

    Echer Márcia de Moraes

    2002-01-01

    Full Text Available Traditional sweet pepper cultivars showing susceptibility to the Potato virus Y (PVY are being replaced by resistant hybrids with higher commercial value. Despite of much information about resistance source reaction and their inheritance, there is no knowledge about the genetic background of commercial resistant hybrids. Reaction of sweet pepper (Capsicum annuum L. hybrids to the Potato virus Y (PVYm such as Acuario, Magali R, Nathalie and their respective generations F2 and F3 as well as hybrids Amanda, Corteso W208, CPC-6272, Dagmar, Elisa, Magali, Margarita, Monteiro, Quantum, Vivo W205 was evaluated. Reaction to PVYm was evaluated as resistant or susceptible. Magali R and Nathalie hybrid did not show any mosaic symptoms. Magali R and Nathalie hybrids resistance is due to a single dominant gene indicating resistant versus susceptible parental lines crossing pedigree. Amanda, Acuario, Corteso W208, Dagmar, Elisa, Margarita, Monteiro, Quantum and Vivo W205, considered resistant to PVY, were highly susceptibility to PVY strain m. Hybrids, claimed as resistant to the Pepper mottle virus (PepMoV, were also resistant to PVYm.

  12. The P2 of Wheat yellow mosaic virus rearranges the endoplasmic reticulum and recruits other viral proteins into replication-associated inclusion bodies.

    Science.gov (United States)

    Sun, Liying; Andika, Ida Bagus; Shen, Jiangfeng; Yang, Di; Chen, Jianping

    2014-06-01

    Viruses commonly modify host endomembranes to facilitate biological processes in the viral life cycle. Infection by viruses belonging to the genus Bymovirus (family Potyviridae) has long been known to induce the formation of large membranous inclusion bodies in host cells, but their assembly and biological roles are still unclear. Immunoelectron microscopy of cells infected with the bymovirus Wheat yellow mosaic virus (WYMV) showed that P1, P2 and P3 are the major viral protein constituents of the membranous inclusions, whereas NIa-Pro (nuclear inclusion-a protease) and VPg (viral protein genome-linked) are probable minor components. P1, P2 and P3 associated with the endoplasmic reticulum (ER), but only P2 was able to rearrange ER and form large aggregate structures. Bioinformatic analyses and chemical experiments showed that P2 is an integral membrane protein and depends on the active secretory pathway to form aggregates of ER membranes. In planta and in vitro assays demonstrated that P2 interacts with P1, P3, NIa-Pro or VPg and recruits these proteins into the aggregates. In vivo RNA labelling using WYMV-infected wheat protoplasts showed that the synthesis of viral RNAs occurs in the P2-associated inclusions. Our results suggest that P2 plays a major role in the formation of membranous compartments that house the genomic replication of WYMV. © 2013 BSPP AND JOHN WILEY & SONS LTD.

  13. Zika Virus, a Cause of Fever in Central Java, Indonesia

    Science.gov (United States)

    1981-01-01

    considered with the isolation of ZIKA Lee, V. H. & Moore, D. L. (1972). Vectors of the virus from a variety of other Aedes of the subgenus 1969 yellow...a vector of the virus . 46, 669-673. Marchette, N. J., Garcia, R. & Rudnick, A. (1969). Acknowledgements Isolation of Zika virus from Aedes aegypti mos...hemagglutination test for the diagnosis of human Twelve isolations of Zika virus from Aedes leptospirosis. Journal of Clinical Microbiology

  14. [Yellow fever: reemerging in the state of Sao Paulo, Brazil, 2009].

    Science.gov (United States)

    Mascheretti, Melissa; Tengan, Ciléa H; Sato, Helena Keiko; Suzuki, Akemi; de Souza, Renato Pereira; Maeda, Marina; Brasil, Roosecelis; Pereira, Mariza; Tubaki, Rosa Maria; Wanderley, Dalva M V; Fortaleza, Carlos Magno Castelo Branco; Ribeiro, Ana Freitas

    2013-10-01

    To describe the investigation of a sylvatic yellow fever outbreak in the state of Sao Paulo and the main control measures undertaken. This is a descriptive study of a sylvatic yellow fever outbreak in the Southwestern region of the state from February to April 2009. Suspected and confirmed cases in humans and in non-human primates were evaluated. Entomological investigation in sylvatic environment involved capture at ground level and in the tree canopy to identify species and detect natural infections. Control measures were performed in urban areas to control Aedes aegypti . Vaccination was directed at residents living in areas with confirmed viral circulation and also at nearby cities according to national recommendation. Twenty-eight human cases were confirmed (39.3% case fatality rate) in rural areas of Sarutaiá, Piraju, Tejupá, Avaré and Buri. The deaths of 56 non-human primates were also reported, 91.4% were Allouatta sp. Epizootics was confirmed in two non-human primates in the cities of Itapetininga and Buri. A total of 1,782 mosquitoes were collected, including Haemagogus leucocelaenus , Hg. janthinomys/capricornii , and Sabethes chloropterus, Sa. purpureus and Sa. undosus . Yellow fever virus was isolated from a group of Hg. Leucocelaenus from Buri. Vaccination was carried out in 49 cities, with a total of 1,018,705 doses. Nine serious post-vaccination adverse events were reported. The cases occurred between February and April 2009 in areas with no recorded yellow fever virus circulation in over 60 years. The outbreak region occurred outside the original recommended vaccination area with a high percentage of susceptible population. The fast adoption of control measures interrupted the human transmission within a month and the confirmation of viral circulation in humans, monkeys and mosquitoes. The results allowed the identification of new areas of viral circulation but further studies are required to clarify the dynamics of the spread of this disease.

  15. IDENTIFICATION AND CHARACTERIZATION OF CARMOVIRUS ON CARNATION (Dianthus caryophyllus L. IN WEST JAVA, INDONESIA

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    Erniawati Diningsih

    2015-06-01

    Full Text Available Carnation has a highly economic demand of cut flower in Indonesia. Field observations in West Java Indonesia was conducted in order to find the typical mottle symptoms that was a suspect caused by a virus disease. Identification of the virus was respectively conducted by performing ELISA test with four anti sera and characterizations held by bioassay, observing of virion particles, detecting of nucleic acid by RT-PCR and nucleotide sequencing. Total of 403 samples were collected from plants with or no virus-like symptoms. Among those all tested, 83% were found to be infected by Carnation mottle virus (CarMV, but negatively against Carnation ringspot virus (CRSV, Carnation laten virus (CLV, and Carnation vein mottle virus (CVMV antisera. By mechanical inoculation, the virus was able to infect systemically Cenopodium quinoa and locally infect on others. However on Phalaenopsis sp and Gomprena globosa, there was symptompless found. The isometric CarMV particles size was approximately 30 nm. RT-PCR using specific primers of CP gene of CarMV successfully amplified a DNA sized 1000 bp. CarMV West Java Indonesian (Idn-WJ isolates possessed the highest nucleotide and amino acid homology with CarMV from Spain and was in the same cluster with CarMV from China, Taiwan and Israel.

  16. The First Report of KRT5 Mutation Underlying Acantholytic Dowling-Degos Disease with Mottled Hypopigmentation in an Indian Family

    Science.gov (United States)

    Verma, Shyam; Pasternack, Sandra M.; Rütten, Arno; Ruzicka, Thomas; Betz, Regina C.; Hanneken, Sandra

    2014-01-01

    Galli Galli disease (GGD) is the name given to a rare form of acantholytic Dowling-Degos disease. (DDD), the latter itself being a rare condition. We believe we are describing for the first time in Indian dermatologic literature a case of GGD in a family where 25 persons have DDD and have been able to document a KRT5 mutation in four members of the family. Whereas reticulate pigmentation is a hallmark of DDD there are rare reports of mottled pigmentation with multiple asymptomatic hypopigmented macules scattered diffusely along with the pigmentation. All the cases described here show a mottled pigmentation comprising hypo and hyperpigmented asymptomatic macules. After the clinical diagnosis was made by one of the authors (SV) in India, the German authors repeated histological examination and successfully demonstrated a heterozygous nonsense mutation, c.C10T (p.Gln4X), in exon 1 of the KRT5 gene, from various centers in Munich, Bonn, Dusseldorf and Friedrichschafen in Germany. PMID:25284854

  17. Label-free virus detection using silicon photonic microring resonators.

    Science.gov (United States)

    McClellan, Melinda S; Domier, Leslie L; Bailey, Ryan C

    2012-01-15

    Viruses represent a continual threat to humans through a number of mechanisms, which include disease, bioterrorism, and destruction of both plant and animal food resources. Many contemporary techniques used for the detection of viruses and viral infections suffer from limitations such as the need for extensive sample preparation or the lengthy window between infection and measurable immune response, for serological methods. In order to develop a method that is fast, cost-effective, and features reduced sample preparation compared to many other virus detection methods, we report the application of silicon photonic microring resonators for the direct, label-free detection of intact viruses in both purified samples as well as in a complex, real-world analytical matrix. As a model system, we demonstrate the quantitative detection of Bean pod mottle virus, a pathogen of great agricultural importance, with a limit of detection of 10 ng/mL. By simply grinding a small amount of leaf sample in buffer with a mortar and pestle, infected leaves can be identified over a healthy control with a total analysis time of less than 45 min. Given the inherent scalability and multiplexing capability of the semiconductor-based technology, we feel that silicon photonic microring resonators are well-positioned as a promising analytical tool for a number of viral detection applications. Copyright © 2011 Elsevier B.V. All rights reserved.

  18. Detection of beet soil-borne virus and beet virus Q in sugarbeet in Greece

    NARCIS (Netherlands)

    Pavli, R.; Prins, M.; Skaracis, G.N.

    2010-01-01

    Sugar beet plants with typical rhizomania symptoms were collected from the five major cultivation zones of Greece. The presence of Beet necrotic yellow vein virus (BNYVV), the primary causal agent of the disease, was ascertained by DAS-ELISA in 38 out of 40 fields surveyed and the positive samples

  19. Systematic analysis of protein identity between Zika virus and other arthropod-borne viruses.

    Science.gov (United States)

    Chang, Hsiao-Han; Huber, Roland G; Bond, Peter J; Grad, Yonatan H; Camerini, David; Maurer-Stroh, Sebastian; Lipsitch, Marc

    2017-07-01

    To analyse the proportions of protein identity between Zika virus and dengue, Japanese encephalitis, yellow fever, West Nile and chikungunya viruses as well as polymorphism between different Zika virus strains. We used published protein sequences for the Zika virus and obtained protein sequences for the other viruses from the National Center for Biotechnology Information (NCBI) protein database or the NCBI virus variation resource. We used BLASTP to find regions of identity between viruses. We quantified the identity between the Zika virus and each of the other viruses, as well as within-Zika virus polymorphism for all amino acid k -mers across the proteome, with k ranging from 6 to 100. We assessed accessibility of protein fragments by calculating the solvent accessible surface area for the envelope and nonstructural-1 (NS1) proteins. In total, we identified 294 Zika virus protein fragments with both low proportion of identity with other viruses and low levels of polymorphisms among Zika virus strains. The list includes protein fragments from all Zika virus proteins, except NS3. NS4A has the highest number (190 k -mers) of protein fragments on the list. We provide a candidate list of protein fragments that could be used when developing a sensitive and specific serological test to detect previous Zika virus infections.

  20. Yellow fever

    Science.gov (United States)

    ... to thrive. Blood tests can confirm the diagnosis. Treatment There is no specific treatment for yellow fever. ... SJ, Endy TP, Rothman AL, Barrett AD. Flaviviruses (dengue, yellow fever, Japanese encephalitis, West Nile encephalitis, St. ...

  1. Molecular characterization of a new begomovirus associated with leaf yellow mosaic disease of Jatropha curcas in India.

    Science.gov (United States)

    Srivastava, Ashish; Kumar, S; Jaidi, Meraj; Raj, S K

    2015-05-01

    During a survey in June 2011, severe leaf yellow mosaic disease was observed on about 45 % plants of Jatropha curcas growing in the Katerniaghat wildlife sanctuary in India. An association of a begomovirus with disease was detected in 15 out of 20 samples by PCR using begomovirus genus-specific primers and total DNA isolated from symptomatic leaf samples. For identification of the begomovirus, the complete genome was amplified using a Phi-29 DNA-polymerase-based rolling-circle amplification kit and total DNA from five representative samples and then digested with BamHI. The linearized RCA products were cloned and sequenced. Their GenBank accession numbers are JN698954 (SKRK1) and JN135236 (SKRK2). The sequences of the two begomovirus isolates were 97 % identical to each other and no more than 86 % to those of jatropha mosaic India virus (JMIV, HM230683) and other begomoviruses reported worldwide. In phylogenetic analysis, SKRK1 and SKRK2 clustered together and showed distant relationships to jatropha mosaic India virus, Jatropha curcas mosaic virus, Indian cassava mosaic virus, Sri Lankan cassava mosaic virus and other begomoviruses. Based on 86 % sequence identities and distant phylogenetic relationships to JMIV and other begomoviruses and the begomovirus species demarcation criteria of the ICTV (curcas were identified as members of a new begomovirus species and provisionally designated as jatropha leaf yellow mosaic Katerniaghat virus (JLYMKV). Agroinfectious clones of the DNA molecule of the begomovirus isolate were also generated, and the fulfillment of Koch's postulates was demonstrated in J. curcas plants.

  2. Human cytomegaloviruses expressing yellow fluorescent fusion proteins--characterization and use in antiviral screening.

    Directory of Open Access Journals (Sweden)

    Sarah Straschewski

    Full Text Available Recombinant viruses labelled with fluorescent proteins are useful tools in molecular virology with multiple applications (e.g., studies on intracellular trafficking, protein localization, or gene activity. We generated by homologous recombination three recombinant cytomegaloviruses carrying the enhanced yellow fluorescent protein (EYFP fused with the viral proteins IE-2, ppUL32 (pp150, and ppUL83 (pp65. In growth kinetics, the three viruses behaved all like wild type, even at low multiplicity of infection (MOI. The expression of all three fusion proteins was detected, and their respective localizations were the same as for the unmodified proteins in wild-type virus-infected cells. We established the in vivo measurement of fluorescence intensity and used the recombinant viruses to measure inhibition of viral replication by neutralizing antibodies or antiviral substances. The use of these viruses in a pilot screen based on fluorescence intensity and high-content analysis identified cellular kinase inhibitors that block viral replication. In summary, these viruses with individually EYFP-tagged proteins will be useful to study antiviral substances and the dynamics of viral infection in cell culture.

  3. Preliminary X-ray data analysis of crystalline hibiscus chlorotic ringspot virus

    International Nuclear Information System (INIS)

    Cheng, Ao; Speir, Jeffrey A.; Yuan, Y. Adam; Johnson, John E.; Wong, Sek-Man

    2009-01-01

    Hibiscus chlorotic ringspot virus is a positive-sense monopartite single-stranded RNA virus that belongs to the Carmovirus genus of the Tombusviridae family. Authentic virus harvested from infected host kenaf leaves was purified and virus crystals were grown in multiple conditions. One of the crystals diffracted to 3.2 Å resolution and allowed the collection of a partial data set. Hibiscus chlorotic ringspot virus (HCRSV) is a positive-sense monopartite single-stranded RNA virus that belongs to the Carmovirus genus of the Tombusviridae family, which includes carnation mottle virus (CarMV). The HCRSV virion has a 30 nm diameter icosahedral capsid with T = 3 quasi-symmetry containing 180 copies of a 38 kDa coat protein (CP) and encapsidates a full-length 3.9 kb genomic RNA. Authentic virus was harvested from infected host kenaf leaves and was purified by saturated ammonium sulfate precipitation, sucrose density-gradient centrifugation and anion-exchange chromatography. Virus crystals were grown in multiple conditions; one of the crystals diffracted to 3.2 Å resolution and allowed the collection of a partial data set. The crystal belonged to space group R32, with unit-cell parameters a = b = 336.4, c = 798.5 Å. Packing considerations and rotation-function analysis determined that there were three particles per unit cell, all of which have the same orientation and fixed positions, and resulted in tenfold noncrystallography symmetry for real-space averaging. The crystals used for the structure determination of southern bean mosaic virus (SBMV) have nearly identical characteristics. Together, these findings will greatly aid the high-resolution structure determination of HCRSV

  4. Virus Incidence of Sweet Potato in Korea from 2011 to 2014.

    Science.gov (United States)

    Kim, Jaedeok; Yang, Jung Wook; Kwak, Hae-Ryun; Kim, Mi-Kyeong; Seo, Jang-Kyun; Chung, Mi-Nam; Lee, Hyeong-Un; Lee, Kyeong-Bo; Nam, Sang Sik; Kim, Chang-Seok; Lee, Gwan-Seok; Kim, Jeong-Soo; Lee, Sukchan; Choi, Hong-Soo

    2017-10-01

    A nationwide survey was performed to investigate the current incidence of viral diseases in Korean sweet potatoes for germplasm and growing fields from 2011 to 2014. A total of 83.8% of the germplasm in Korea was infected with viruses in 2011. Commercial cultivars that were used to supply growing fields were infected at a rate of 62.1% in 2012. Among surveyed viruses, the incidence of five Potyvirus species that infect sweet potato decreased between 2012 and 2013, and then increased again in 2014. Representatively, the incidence of Sweet potato feathery mottle virus (SPFMV) was 87.0% in 2012, 20.7% in 2013 and then increased to 35.3% in 2014. Unlike RNA viruses, DNA viruses were shown to decrease continuously. The incidence of Sweet potato leaf curl virus (SPLCV) was 5.5% in 2003, 59.5% in 2011, and 47.4% in 2012. It then decreased continuously year by year to 33.2% in 2013, and then 25.6% in 2014. While the infection rate of each virus species showed a tendency to decline, the virus infection status was more variable in 2013 and 2014. Nevertheless, the high rate of single infections and mixed infection combinations were more variable than the survey results from 2012. As shown in the results from 2013, the most prevalent virus infection was a single infection at 27.6%, with the highest rate of infection belonging to sweet potato symptomless virus-1 (SPSMV-1) (12.9%). Compared to 2013, infection combinations were more varied in 2014, with a total of 122 kinds of mixed infection.

  5. Simultaneous detection of three lily viruses using Triplex IC-RT-PCR.

    Science.gov (United States)

    Zhang, Yubao; Wang, Yajun; Xie, Zhongkui; Yang, Guo; Guo, Zhihong; Wang, Le

    2017-11-01

    Viruses commonly infecting lily (Lilium spp.) include: Lily symptomless virus (LSV), Cucumber mosaic virus (CMV) and Lily mottle virus (LMoV). These viruses usually co-infect lilies causing severe economic losses in terms of quantity and quality of flower and bulb production around the world. Reliable and precise detection systems need to be developed for virus identification. We describe the development of a triplex immunocapture (IC) reverse transcription (RT) polymerase chain reaction (PCR) assay for the simultaneous detection of LSV, CMV and LMoV. The triplex IC-RT-PCR was compared with a quadruplex RT-PCR assay. Relative to the quadruplex RT-PCR, the specificity of the triplex IC-RT-PCR system for LSV, CMV and LMoV was 100% for field samples. The sensitivity of the triplex IC-RT-PCR system was 99.4%, 81.4% and 98.7% for LSV, CMV and LMoV, respectively. Agreement (κ) between the results obtained from the two tests was 0.968, 0.844 and 0.984 for LSV, CMV and LMoV, respectively. This is the first report of the simultaneous detection of LSV, CMV and LMoV in a triplex IC-RT-PCR assay. In particular we believe this convenient and reliable triplex IC-RT-PCR method could be used routinely for large-scale field surveys or crop health monitoring of lily. Copyright © 2017. Published by Elsevier B.V.

  6. Additive interactions of unrelated viruses in mixed infections of cowpea.

    Directory of Open Access Journals (Sweden)

    Imade Yolanda Nsa

    2015-10-01

    Full Text Available This study was carried out to determine the effects of single infections and co-infections of three unrelated viruses on three cowpea cultivars (one commercial cowpea cultivar White and 2 IITA lines; IT81D-985 and TVu76. The plants were inoculated with Cowpea aphid-borne mosaic virus (CABMV, genus Potyvirus, Cowpea mottle virus (CMeV, genus Carmovirus and Southern bean mosaic virus (SBMV, genus Sobemovirus singly and in mixture (double and triple at 10, 20 and 30 days after planting (DAP. The treated plants were assessed for susceptibility to the viruses, growth and yield. In all cases of infection, early inoculation resulted in higher disease severity compared with late infection. The virus treated cowpea plants were relatively shorter than buffer inoculated control plants except the IT81D-985 plants that were taller and produced more foliage. Single infections by CABMV, CMeV and SBMV led to a complete loss of seeds in the three cowpea cultivars at 10DAP; only cultivar White produced some seeds at 30DAP. Double and triple virus infections led to a total loss of seeds in all three cowpea cultivars. None of the virus infected IITA lines produced any seeds except IT81D-985 plants co-infected with CABMV and SBMV at 30DAP with a reduction of 80%. Overall, the commercial cultivar White was the least susceptible to the virus treatments and produced the most yield (flowers, pods and seeds. CABMV was the most aggressive of these viruses and early single inoculations with this virus resulted in the premature death of some of the seedlings. The presence of the Potyvirus, CABMV in the double virus infections did not appear to increase disease severity or yield loss. There was no strong evidence for synergistic interactions between the viruses in the double virus mixtures.

  7. Survey of virus pathogens in gladiolus, iris and tulips in the Czech Republic

    Directory of Open Access Journals (Sweden)

    Ganesh Selvaraj Duraisamy

    2009-01-01

    Full Text Available The occurrence of Bean yellow mosaic virus (BYMV, Cucumber mosaic virus (CMV Tobacco rattle virus (TRV in gladiolus, iris, tulip and Iris yellow spot virus (IYSV in iris was investigated by examining the plants by the means of serological techniques (ELISA. ELISA was applied to determine the presence of BYMV, CMV, TRV infections in both aerial and underground parts of gladiolus, iris, and tulip, and IYSV on the aerial parts of iris, respectively. 262 gladiolus plants were tested. 63.7% was infected by BYMV, 29.4 % by CMV, and 2.7 % by TRV. Out of 180 plants of iris, 1.1% was infected by BYMV, 6.7% by CMV, 2.8% by TRV, and 0% by IYSV. Out of 28 plants of tulip, 28.6% was infected by CMV, and 7.1% by TRV. ELISA proved to be a suitable method for detection of viruses in leaves of these ornamental plants, but it often failed to detect viruses in flowers and corms. A high transmission of BYMV by gladiolus cormlets was also found.

  8. Impact of transgenic wheat with wheat yellow mosaic virus resistance on microbial community diversity and enzyme activity in rhizosphere soil.

    Science.gov (United States)

    Wu, Jirong; Yu, Mingzheng; Xu, Jianhong; Du, Juan; Ji, Fang; Dong, Fei; Li, Xinhai; Shi, Jianrong

    2014-01-01

    The transgenic wheat line N12-1 containing the WYMV-Nib8 gene was obtained previously through particle bombardment, and it can effectively control the wheat yellow mosaic virus (WYMV) disease transmitted by Polymyxa graminis at turngreen stage. Due to insertion of an exogenous gene, the transcriptome of wheat may be altered and affect root exudates. Thus, it is important to investigate the potential environmental risk of transgenic wheat before commercial release because of potential undesirable ecological side effects. Our 2-year study at two different experimental locations was performed to analyze the impact of transgenic wheat N12-1 on bacterial and fungal community diversity in rhizosphere soil using polymerase chain reaction-denaturing gel gradient electrophoresis (PCR-DGGE) at four growth stages (seeding stage, turngreen stage, grain-filling stage, and maturing stage). We also explored the activities of urease, sucrase and dehydrogenase in rhizosphere soil. The results showed that there was little difference in bacterial and fungal community diversity in rhizosphere soil between N12-1 and its recipient Y158 by comparing Shannon's, Simpson's diversity index and evenness (except at one or two growth stages). Regarding enzyme activity, only one significant difference was found during the maturing stage at Xinxiang in 2011 for dehydrogenase. Significant growth stage variation was observed during 2 years at two experimental locations for both soil microbial community diversity and enzyme activity. Analysis of bands from the gel for fungal community diversity showed that the majority of fungi were uncultured. The results of this study suggested that virus-resistant transgenic wheat had no adverse impact on microbial community diversity and enzyme activity in rhizosphere soil during 2 continuous years at two different experimental locations. This study provides a theoretical basis for environmental impact monitoring of transgenic wheat when the introduced gene is

  9. Impact of transgenic wheat with wheat yellow mosaic virus resistance on microbial community diversity and enzyme activity in rhizosphere soil.

    Directory of Open Access Journals (Sweden)

    Jirong Wu

    Full Text Available The transgenic wheat line N12-1 containing the WYMV-Nib8 gene was obtained previously through particle bombardment, and it can effectively control the wheat yellow mosaic virus (WYMV disease transmitted by Polymyxa graminis at turngreen stage. Due to insertion of an exogenous gene, the transcriptome of wheat may be altered and affect root exudates. Thus, it is important to investigate the potential environmental risk of transgenic wheat before commercial release because of potential undesirable ecological side effects. Our 2-year study at two different experimental locations was performed to analyze the impact of transgenic wheat N12-1 on bacterial and fungal community diversity in rhizosphere soil using polymerase chain reaction-denaturing gel gradient electrophoresis (PCR-DGGE at four growth stages (seeding stage, turngreen stage, grain-filling stage, and maturing stage. We also explored the activities of urease, sucrase and dehydrogenase in rhizosphere soil. The results showed that there was little difference in bacterial and fungal community diversity in rhizosphere soil between N12-1 and its recipient Y158 by comparing Shannon's, Simpson's diversity index and evenness (except at one or two growth stages. Regarding enzyme activity, only one significant difference was found during the maturing stage at Xinxiang in 2011 for dehydrogenase. Significant growth stage variation was observed during 2 years at two experimental locations for both soil microbial community diversity and enzyme activity. Analysis of bands from the gel for fungal community diversity showed that the majority of fungi were uncultured. The results of this study suggested that virus-resistant transgenic wheat had no adverse impact on microbial community diversity and enzyme activity in rhizosphere soil during 2 continuous years at two different experimental locations. This study provides a theoretical basis for environmental impact monitoring of transgenic wheat when the

  10. Recent progress in West Nile virus diagnosis and vaccination

    Directory of Open Access Journals (Sweden)

    De Filette Marina

    2012-03-01

    Full Text Available Abstract West Nile virus (WNV is a positive-stranded RNA virus belonging to the Flaviviridae family, a large family with 3 main genera (flavivirus, hepacivirus and pestivirus. Among these viruses, there are several globally relevant human pathogens including the mosquito-borne dengue virus (DENV, yellow fever virus (YFV, Japanese encephalitis virus (JEV and West Nile virus (WNV, as well as tick-borne viruses such as tick-borne encephalitis virus (TBEV. Since the mid-1990s, outbreaks of WN fever and encephalitis have occurred throughout the world and WNV is now endemic in Africa, Asia, Australia, the Middle East, Europe and the Unites States. This review describes the molecular virology, epidemiology, pathogenesis, and highlights recent progress regarding diagnosis and vaccination against WNV infections.

  11. Induced Förster resonance energy transfer by encapsulation of DNA-scaffold based probes inside a plant virus based protein cage

    Science.gov (United States)

    de Ruiter, Mark V.; Overeem, Nico J.; Singhai, Gaurav; Cornelissen, Jeroen J. L. M.

    2018-05-01

    Insight into the assembly and disassembly of viruses can play a crucial role in developing cures for viral diseases. Specialized fluorescent probes can benefit the study of interactions within viruses, especially during cell studies. In this work, we developed a strategy based on Förster resonance energy transfer (FRET) to study the assembly of viruses without labeling the exterior of viruses. Instead, we exploit their encapsulation of nucleic cargo, using three different fluorescent ATTO dyes linked to single-stranded DNA oligomers, which are hybridised to a longer DNA strand. FRET is induced upon assembly of the cowpea chlorotic mottle virus, which forms monodisperse icosahedral particles of about 22 nm, thereby increasing the FRET efficiency by a factor of 8. Additionally, encapsulation of the dyes in virus-like particles induces a two-step FRET. When the formed constructs are disassembled, this FRET signal is fully reduced to the value before encapsulation. This reversible behavior makes the system a good probe for studying viral assembly and disassembly. It, furthermore, shows that multi-component supramolecular materials are stabilized in the confinement of a protein cage.

  12. Functional replacement of Wheat streak mosaic virus HC-Pro with the corresponding cistron from a diverse array of viruses in the family Potyviridae

    International Nuclear Information System (INIS)

    Stenger, Drake C.; French, Roy

    2004-01-01

    Helper component-proteinase (HC-Pro) of Wheat streak mosaic virus strain Sidney 81 (WSMV-Sidney 81) was systematically replaced with the corresponding cistron derived from four strains of WSMV (Type, TK1, CZ, and El Batan 3), the tritimovirus Oat necrotic mottle virus (ONMV), the rymoviruses Agropyron mosaic virus (AgMV) and Hordeum mosaic virus (HoMV), or the potyviruses Tobacco etch virus (TEV) and Turnip mosaic virus (TuMV). These HC-Pro proteins varied in amino acid sequence identity shared with HC-Pro of WSMV-Sidney 81 from high (strains of WSMV at ∼86-99%) to moderate (ONMV at 70%) to low (rymoviruses and potyviruses at ∼15-17%). Surprisingly, all chimeric viral genomes examined were capable of systemic infection of wheat upon inoculation with RNA transcripts produced in vitro. HC-Pro replacements derived from tritimoviruses did not alter host range relative to WSMV-Sidney 81, as each of these chimeric viruses was able to systemically infect wheat, oat, and corn line SDp2. These results indicate that differences in host range among tritimoviruses, including the inability of ONMV to infect wheat or the inability of WSMV strains Type and El Batan 3 to infect SDp2 corn, are not determined by HC-Pro. In contrast, all chimeric viruses bearing HC-Pro replacements derived from rymoviruses or potyviruses were unable to infect SDp2 corn and oat. Collectively, these results indicate that HC-Pro from distantly related virus species of the family Potyviridae are competent to provide WSMV-Sidney 81 with all functions necessary for infection of a permissive host (wheat) and that virus-host interactions required for systemic infection of oat and SDp2 corn are more stringent. Changes in symptom severity or mechanical transmission efficiency observed for some chimeric viruses further suggest that HC-Pro affects virulence in WSMV

  13. Geographic patterns and environmental factors associated with human yellow fever presence in the Americas.

    Science.gov (United States)

    Hamrick, Patricia Najera; Aldighieri, Sylvain; Machado, Gustavo; Leonel, Deise Galan; Vilca, Luz Maria; Uriona, Sonia; Schneider, Maria Cristina

    2017-09-01

    In the Americas, yellow fever virus transmission is a latent threat due to the proximity between urban and wild environments. Although yellow fever has nearly vanished from North and Central America, there are still 13 countries in the Americas considered endemic by the World Health Organization. Human cases usually occur as a result of the exposure to sylvatic yellow fever in tropical forested environments; but urban outbreaks reported during the last decade demonstrate that the risk in this environment still exists. The objective of this study was to identify spatial patterns and the relationship between key geographic and environmental factors with the distribution of yellow fever human cases in the Americas. An ecological study was carried out to analyze yellow fever human cases reported to the Pan American Health Organization from 2000 to 2014, aggregated by second administrative level subdivisions (counties). Presence of yellow fever by county was used as the outcome variable and eight geo-environmental factors were used as independent variables. Spatial analysis was performed to identify and examine natural settings per county. Subsequently, a multivariable logistic regression model was built. During the study period, 1,164 cases were reported in eight out of the 13 endemic countries. Nearly 83.8% of these cases were concentrated in three countries: Peru (37.4%), Brazil (28.1%) and Colombia (18.4%); and distributed in 57 states/provinces, specifically in 286 counties (3.4% of total counties). Yellow fever presence was significantly associated with altitude, rain, diversity of non-human primate hosts and temperature. A positive spatial autocorrelation revealed a clustered geographic pattern in 138/286 yellow fever positive counties (48.3%). A clustered geographic pattern of yellow fever was identified mostly along the Andes eastern foothills. This risk map could support health policies in endemic countries. Geo-environmental factors associated with presence

  14. Vaccination with Replication Deficient Adenovectors Encoding YF-17D Antigens Induces Long-Lasting Protection from Severe Yellow Fever Virus Infection in Mice

    DEFF Research Database (Denmark)

    Bassi, Maria R; Larsen, Mads Andreas Bay; Kongsgaard, Michael

    2016-01-01

    The live attenuated yellow fever vaccine (YF-17D) has been successfully used for more than 70 years. It is generally considered a safe vaccine, however, recent reports of serious adverse events following vaccination have raised concerns and led to suggestions that even safer YF vaccines should...... be developed. Replication deficient adenoviruses (Ad) have been widely evaluated as recombinant vectors, particularly in the context of prophylactic vaccination against viral infections in which induction of CD8+ T-cell mediated immunity is crucial, but potent antibody responses may also be elicited using......, which afforded a high degree of protection from subsequent intracranial challenge of vaccinated mice. However, full protection was only observed using a vector encoding the structural proteins from YF-17D. This vector elicited virus-specific CD8+ T cells as well as neutralizing antibodies, and both...

  15. [YEL-AND meningoencephalitis in a 4-year-old boy consecutive to a yellow-fever vaccine].

    Science.gov (United States)

    Gerin, M; Wroblewski, I; Bost-Bru, C; N'guyen, M-A; Debillon, T

    2014-04-01

    Yellow fever is a vector-borne disease transmitted by an endemic mosquito in sub-Saharan Africa and tropical South America. It causes fever and possibly liver and renal failure with hemorrhagic signs, which may be fatal. The yellow-fever vaccine is an attenuated vaccine that is recommended for all travelers over the age of 9 months in high-risk areas. Adverse effects have been reported: minor symptoms (such as viral syndrome), hypersensitivity reactions, and major symptoms such as viscerotropic disease (YEL-AVD) and neurotropic disease (YEL-AND). The yellow-fever vaccine-associated autoimmune disease with central nervous system involvement (such as acute disseminated encephalomyelitis) associates fever and headaches, neurologic dysfunction, seizures, cerebrospinal fluid (CSF) pleocytosis, and elevated protein, with neuroimaging consistent with multifocal areas of demyelization. The presence of antibodies or virus in CSF, within 1-30 days following vaccination, and the exclusion of other causes is necessary for diagnosis. We describe herein the case of a 4-year-old child who presented with severe encephalitis consecutive to a yellow-fever vaccine, with favorable progression. Diagnosis is based on the chronology of clinical and paraclinical signs and the presence of yellow-fever-specific antibodies in CSF. The treatment consists of symptomatic treatment and immunoglobulin injection. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

  16. First recorded outbreak of yellow fever in Kenya, 1992-1993. II. Entomologic investigations.

    Science.gov (United States)

    Reiter, P; Cordellier, R; Ouma, J O; Cropp, C B; Savage, H M; Sanders, E J; Marfin, A A; Tukei, P M; Agata, N N; Gitau, L G; Rapuoda, B A; Gubler, D J

    1998-10-01

    The first recorded outbreak of yellow fever in Kenya occurred from mid-1992 through March 1993 in the south Kerio Valley, Rift Valley Province. We conducted entomologic studies in February-March 1993 to identify the likely vectors and determine the potential for transmission in the surrounding rural and urban areas. Mosquitoes were collected by landing capture and processed for virus isolation. Container surveys were conducted around human habitation. Transmission was mainly in woodland of varying density, at altitudes of 1,300-1,800 m. The abundance of Aedes africanus in this biotope, and two isolations of virus from pools of this species, suggest that it was the principal vector in the main period of the outbreak. A third isolate was made from a pool of Ae. keniensis, a little-known species that was collected in the same biotope. Other known yellow fever vectors that were collected in the arid parts of the valley may have been involved at an earlier stage of the epidemic. Vervet monkeys and baboons were present in the outbreak area. Peridomestic mosquito species were absent but abundant at urban sites outside the outbreak area. The entomologic and epidemiologic evidence indicate that this was a sylvatic outbreak in which human cases were directly linked to the epizootic and were independent of other human cases. The region of the Kerio Valley is probably subject to recurrent wandering epizootics of yellow fever, although previous episodes of scattered human infection have gone unrecorded. The risk that the disease could emerge as an urban problem in Kenya should not be ignored.

  17. Enteric and indicator virus removal by surface flow wetlands.

    Science.gov (United States)

    Rachmadi, Andri T; Kitajima, Masaaki; Pepper, Ian L; Gerba, Charles P

    2016-01-15

    We investigated the occurrence and attenuation of several human enteric viruses (i.e., norovirus, adenovirus, Aichi virus 1, polyomaviruses, and enterovirus) as well as a plant virus, pepper mild mottle virus (PMMoV), at two surface flow wetlands in Arizona. The retention time in one of the wetlands was seven days, whereas in the other wetland it could not be defined. Water samples were collected at the inlet and outlet from the wetlands over nine months, and concentration of viral genomes was determined by quantitative polymerase chain reaction (qPCR). Of the human enteric viruses tested, adenovirus and Aichi virus 1 were found in the greatest prevalence in treated wastewater (i.e., inlet of the wetlands). Reduction efficiencies of enteric viruses by the wetlands ranged from 1 to 3 log10. Polyomaviruses were generally removed to below detection limit, indicating at least 2 to 4 log10 removal. PMMoV was detected in a greater concentration in the inlet of both wetlands for all the viruses tested (10(4) to 10(7) genome copies/L), but exhibited little or no removal (1 log10 or less). To determine the factors associated with virus genome attenuation (as determined by qPCR), the persistence of PMMoV and poliovirus type 1 (an enterovirus) was studied in autoclaved and natural wetland water, and deionized water incubated under three different temperatures for 21 days. A combination of elevated water temperature and biological activities reduced poliovirus by 1 to 4 log10, while PMMoV was not significantly reduced during this time period. Overall, PMMoV showed much greater persistence than human viruses in the wetland treatment. Copyright © 2015 Elsevier B.V. All rights reserved.

  18. [Viruses and civilization].

    Science.gov (United States)

    Chastel, C

    1999-01-01

    A few million years ago, when primates moved from the east African forest to the savannah, they were already infected with endogenous viruses and occultly transmitted them to the prime Homo species. However it was much later with the building of the first large cities in Mesopotamia that interhuman viral transmission began in earnest. Spreading was further enhanced with the organization of the Egyptian, Greek, Roman, and Arab empires around the Mediterranean. Discovery of the New World in 1492 led to an unprecedented clash of civilizations and the destruction of pre-Columbian Indian civilizations. It also led to a rapid spread of viruses across the Atlantic Ocean with the emergence of yellow fever and appearance of smallpox and measles throughout the world. However the greatest opportunities for worldwide viral development have been created by our present, modern civilization. This fact is illustrated by epidemic outbreaks of human immunodeficiency virus, Venezuela hemorrhagic fever, Rift valley fever virus, and monkey pox virus. Close analysis underscores the major role of human intervention in producing these events.

  19. The Aquaporin Gene Family of the Yellow Fever Mosquito, Aedes aegypti

    OpenAIRE

    Drake, Lisa L.; Boudko, Dmitri Y.; Marinotti, Osvaldo; Carpenter, Victoria K.; Dawe, Angus L.; Hansen, Immo A.

    2010-01-01

    Background The mosquito, Aedes aegypti, is the principal vector of the Dengue and yellow fever viruses. During feeding, an adult female can take up more than its own body weight in vertebrate blood. After a blood meal females excrete large amounts of urine through their excretion system, the Malpighian tubules (MT). Diuresis starts within seconds after the mosquito starts feeding. Aquaporins (AQPs) are a family of membrane transporters that regulate the flow of water, glycerol and other small...

  20. Metagenomic-Based Screening and Molecular Characterization of Cowpea-Infecting Viruses in Burkina Faso.

    Science.gov (United States)

    Palanga, Essowè; Filloux, Denis; Martin, Darren P; Fernandez, Emmanuel; Gargani, Daniel; Ferdinand, Romain; Zabré, Jean; Bouda, Zakaria; Neya, James Bouma; Sawadogo, Mahamadou; Traore, Oumar; Peterschmitt, Michel; Roumagnac, Philippe

    2016-01-01

    Cowpea, (Vigna unguiculata L. (Walp)) is an annual tropical grain legume. Often referred to as "poor man's meat", cowpea is one of the most important subsistence legumes cultivated in West Africa due to the high protein content of its seeds. However, African cowpea production can be seriously constrained by viral diseases that reduce yields. While twelve cowpea-infecting viruses have been reported from Africa, only three of these have so-far been reported from Burkina Faso. Here we use a virion-associated nucleic acids (VANA)-based metagenomics method to screen for the presence of cowpea viruses from plants collected from the three agro-climatic zones of Burkina Faso. Besides the three cowpea-infecting virus species which have previously been reported from Burkina Faso (Cowpea aphid borne mosaic virus [Family Potyviridae], the Blackeye cowpea mosaic virus-a strain of Bean common mosaic virus-[Family Potyviridae] and Cowpea mottle virus [Family Tombusviridae]) five additional viruses were identified: Southern cowpea mosaic virus (Sobemovirus genus), two previously uncharacterised polerovirus-like species (Family Luteoviridae), a previously uncharacterised tombusvirus-like species (Family Tombusviridae) and a previously uncharacterised mycotymovirus-like species (Family Tymoviridae). Overall, potyviruses were the most prevalent cowpea viruses (detected in 65.5% of samples) and the Southern Sudan zone of Burkina Faso was found to harbour the greatest degrees of viral diversity and viral prevalence. Partial genome sequences of the two novel polerovirus-like and tombusvirus-like species were determined and RT-PCR primers were designed for use in Burkina Faso to routinely detect all of these cowpea-associated viruses.