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Sample records for plant viruses progress

  1. Future Scenarios for Plant Virus Pathogens as Climate Change Progresses.

    Science.gov (United States)

    Jones, R A C

    2016-01-01

    Knowledge of how climate change is likely to influence future virus disease epidemics in cultivated plants and natural vegetation is of great importance to both global food security and natural ecosystems. However, obtaining such knowledge is hampered by the complex effects of climate alterations on the behavior of diverse types of vectors and the ease by which previously unknown viruses can emerge. A review written in 2011 provided a comprehensive analysis of available data on the effects of climate change on virus disease epidemics worldwide. This review summarizes its findings and those of two earlier climate change reviews and focuses on describing research published on the subject since 2011. It describes the likely effects of the full range of direct and indirect climate change parameters on hosts, viruses and vectors, virus control prospects, and the many information gaps and deficiencies. Recently, there has been encouraging progress in understanding the likely effects of some climate change parameters, especially over the effects of elevated CO2, temperature, and rainfall-related parameters, upon a small number of important plant viruses and several key insect vectors, especially aphids. However, much more research needs to be done to prepare for an era of (i) increasingly severe virus epidemics and (ii) increasing difficulties in controlling them, so as to mitigate their detrimental effects on future global food security and plant biodiversity. © 2016 Elsevier Inc. All rights reserved.

  2. Review. Elimination of viruses in plants: twenty years of progress

    Directory of Open Access Journals (Sweden)

    A. Panattoni

    2013-02-01

    Full Text Available To shed light on trends about elimination of viruses from plants, a bibliographic research was conducted to identify thermotherapy, chemotherapy and tissue culture trials published from 1991 through 2010. Among woody plants, grapevine, apple and peach are the most frequent targets of sanitation protocols because their health status is strictly regulated. Even if thermotherapy represents the preferred method for the host, grapevine viruses can also be eliminated with chemotherapy and tissue culture; apple viruses respond to chemotherapy as well. Although a similar trend was reported among herbaceous plants, chemotherapy was the most frequently used technique in potato. With regard to virus, thermotherapy was successfully applied against viruses belonging to 13 families and an unassigned genus. Instead, chemotherapy and tissue culture techniques eradicated viruses belonging to fewer families (nine. An interpretation of thermotherapy effects considers the new metabolic “pathways” triggered by the natural antiviral response emitted by the infected plant, with particular reference to virus-induced gene silencing. With regard to chemotherapy, several groups of antiviral drugs belong to inosine monophosphate dehydrogenase inhibitors, S-adenosylhomocysteine hydrolase inhibitors, neuraminidase inhibitors. Tissue culture, usually adopted to regenerate plantlets in biotechnological breeding programs, represents the less used tool for eliminate viruses from plants.

  3. Monoclonal antibodies against plant viruses

    International Nuclear Information System (INIS)

    Sandler, E.; Dietzgen, R.G.

    1984-01-01

    Ever since antigenic properties of plant viruses were discovered antisera have been raised and used for plant virus diagnosis and for the analysis of virus structure as well. From the early qualitative diagnosis method of precipitating the virus in clarified sap of an infected plant and the first quantitative application of the precipitin test vast progress has been made with regard to the development of highly sensitive and highly quantitative methods for virus detection. Of equal importance was the improvement of methods for separating virus from host cell components since the specificity of antisera raised against a virus could be increased by using an antigen for immunization highly concentrated and largely freed from contaminating host substances. The introduction of the enzyme-linked immunosorbent assay (ELISA) into plant virology allows detection of virus in nanogram quantities. Still, the conventionally raised antisera, no matter how pure an antigen was used for immunization, are polyclonal. They contain products of thousands of different antibody-secreting plasma cell clones which can be directed against all antigenic determinants (epitopes) of the virus, but also against antigens of the host plant that may not have been entirely separated from the immunizing virus during the purification procedure. Even after cross adsorption of polyclonal antisera some residual heterogeneity can be expected to remain. Within these boundaries the information gained with polyclonal antisera on virus structure and on virus diagnosis has to be interpreted

  4. Protoplasts and plant viruses

    International Nuclear Information System (INIS)

    Murakishi, H.; Lesney, M.S.; Carlson, P.

    1984-01-01

    The use of protoplasts in the study of plant viruses has attracted considerable attention since its inception in the late 1960s. This article is an attempt to assess the current status of protoplasts (primarily) and all cell cultures (in some instances) in studies of virus infection, virus replication, cytopathology, cross-protection, virus resistance, and the use of in vitro methods and genetic engineering to recover virus-resistant plants. These areas of study proved difficult to do entirely with whole plants or plant parts. However, because protoplasts could be synchronously infected with virus, they provided a valuable alternative means of following biochemical and cytological events in relation to the virus growth cycle in a more precise manner than previously possible

  5. 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.

  6. [Research progress on ebola virus glycoprotein].

    Science.gov (United States)

    Ding, Guo-Yong; Wang, Zhi-Yu; Gao, Lu; Jiang, Bao-Fa

    2013-03-01

    Ebola virus (EBOV) causes outbreaks of a highly lethal hemorrhagic fever in humans and there are no effective therapeutic or prophylactic treatments available. The glycoprotein (GP) of EBOV is a transmembrane envelope protein known to play multiple functions including virus attachment and entry, cell rounding and cytotoxicity, down-regulation of host surface proteins, and enhancement of virus assembly and budding. GP is the primary target of protective immunity and the key target for developing neutralizing antibodies. In this paper, the research progress on genetic structure, pathogenesis and immunogenicity of EBOV GP in the last 5 years is reviewed.

  7. Detection of selected plant viruses by microarrays

    OpenAIRE

    HRABÁKOVÁ, Lenka

    2013-01-01

    The main aim of this master thesis was the simultaneous detection of four selected plant viruses ? Apple mosaic virus, Plum pox virus, Prunus necrotic ringspot virus and Prune harf virus, by microarrays. The intermediate step in the process of the detection was optimizing of multiplex polymerase chain reaction (PCR).

  8. Plant virus sensitivity to gamma irradiation

    International Nuclear Information System (INIS)

    Gyoergyne Czeck, B.

    1979-01-01

    Preliminary experiments for prevention were conducted with weakened plant viruses, namely with Arabis mosaic virus isolated from strawberries and tobacco mosaic virus. Treatment 24 hours prior to the infection with the radiation-weakened virus resulted in a 60-70% infection prevention. (author)

  9. Fusion power plant simulations: a progress report

    International Nuclear Information System (INIS)

    Cook, J.M.; Pattern, J.S.; Amend, W.E.

    1976-01-01

    The objective of the fusion systems analysis at ANL is to develop simulations to compare alternative conceptual designs of magnetically confined fusion power plants. The power plant computer simulation progress is described. Some system studies are also discussed

  10. The evolution of plant virus transmission pathways

    Science.gov (United States)

    Frédéric M. Hamelin; Linda J.S. Allen; Holly R. Prendeville; M. Reza Hajimorad; Michael J. Jeger

    2016-01-01

    The evolution of plant virus transmission pathways is studied through transmission via seed, pollen, oravector. We address the questions: under what circumstances does vector transmission make pollen transmission redundant? Can evolution lead to the coexistence of multiple virus transmission pathways? We restrict the analysis to an annual plant population in which...

  11. Transgenic strategies to confer resistance against viruses in rice plants

    Directory of Open Access Journals (Sweden)

    Takahide eSasaya

    2014-01-01

    Full Text Available Rice (Oryza sativa L. is cultivated in more than 100 countries and supports nearly half of the world’s population. Developing efficient methods to control rice viruses is thus an urgent necessity because viruses cause serious losses in rice yield. Most rice viruses are transmitted by insect vectors, notably planthoppers and leafhoppers. Viruliferous insect vectors can disperse their viruses over relatively long distances, and eradication of the viruses is very difficult once they become widespread. Exploitation of natural genetic sources of resistance is one of the most effective approaches to protect crops from virus infection; however, only a few naturally occurring rice genes confer resistance against rice viruses. In an effort to improve control, many investigators are using genetic engineering of rice plants as a potential strategy to control viral diseases. Using viral genes to confer pathogen-derived resistance against crops is a well-established procedure, and the expression of various viral gene products has proved to be effective in preventing or reducing infection by various plant viruses since the 1990s. RNA-interference (RNAi, also known as RNA silencing, is one of the most efficient methods to confer resistance against plant viruses on their respective crops. In this article, we review the recent progress, mainly conducted by our research group, in transgenic strategies to confer resistance against tenuiviruses and reoviruses in rice plants. Our findings also illustrate that not all RNAi constructs against viral RNAs are equally effective in preventing virus infection and that it is important to identify the viral Achilles’ heel gene to target for RNAi attack when engineering plants.

  12. 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.

  13. Engineering resistance to plant viruses: Present status and future prospects

    Science.gov (United States)

    Plant viruses cause severe crop losses across the globe. Resistant cultivars together with pesticide application are commonly used to avoid the losses caused by plant viruses. However, very limited success has been achieved at diminishing the impact of plant viruses. Use of virus resistant plant is ...

  14. Resistance mechanisms to plant viruses: an overview

    NARCIS (Netherlands)

    Goldbach, R.W.; Bucher, E.C.; Prins, A.H.

    2003-01-01

    To obtain virus-resistant host plants, a range of operational strategies can be followed nowadays. While for decades plant breeders have been able to introduce natural resistance genes in susceptible genotypes without knowing precisely what these resistance traits were, currently a growing number of

  15. Ins and Outs of Multipartite Positive-Strand RNA Plant Viruses: Packaging versus Systemic Spread

    Directory of Open Access Journals (Sweden)

    Mattia Dall’Ara

    2016-08-01

    Full Text Available Viruses possessing a non-segmented genome require a specific recognition of their nucleic acid to ensure its protection in a capsid. A similar feature exists for viruses having a segmented genome, usually consisting of viral genomic segments joined together into one viral entity. While this appears as a rule for animal viruses, the majority of segmented plant viruses package their genomic segments individually. To ensure a productive infection, all viral particles and thereby all segments have to be present in the same cell. Progression of the virus within the plant requires as well a concerted genome preservation to avoid loss of function. In this review, we will discuss the “life aspects” of chosen phytoviruses and argue for the existence of RNA-RNA interactions that drive the preservation of viral genome integrity while the virus progresses in the plant.

  16. Fungal transmission of plant viruses.

    Science.gov (United States)

    Campbell, R N

    1996-01-01

    Thirty soilborne viruses or virus-like agents are transmitted by five species of fungal vectors. Ten polyhedral viruses, of which nine are in the family Tombusviridae, are acquired in the in vitro manner and do not occur within the resting spores of their vectors, Olpidium brassicae and O. bornovanus. Fungal vectors for other viruses in the family should be sought even though tombusviruses are reputed to be soil transmitted without a vector. Eighteen rod-shaped viruses belonging to the furo- and bymovirus groups and to an unclassified group are acquired in the in vivo manner and survive within the resting spores of their vector, O. brassicae, Polymyxa graminis, P. betae, and Spongospora subterranea. The viral coat protein has an essential role in in vitro transmission. With in vivo transmission a site in the coat protein-read through protein (CP-RT) of beet necrotic yellow vein furovirus determines vector transmissibility as does a site in a similar 98-kDa polyprotein of barley mild mosaic bymovirus. The mechanisms by which virions move (or are moved) into and out of the protoplasm of zoospores or of thalli needs study.

  17. Better Plants Progress Update Fall 2013

    Energy Technology Data Exchange (ETDEWEB)

    none,

    2013-09-23

    This Progress Update summarizes the significant energy saving achievements and cumulative cost savings made by these industry leaders from 2010-2012. The update also shares the plans and priorities over the next year for the Better Plants Program to continue to advance energy efficiency in the industrial sector.

  18. Engineering Molecular Immunity Against Plant Viruses

    KAUST Repository

    Zaidi, Syed Shan-e-Ali

    2017-04-26

    Genomic engineering has been used to precisely alter eukaryotic genomes at the single-base level for targeted gene editing, replacement, fusion, and mutagenesis, and plant viruses such as Tobacco rattle virus have been developed into efficient vectors for delivering genome-engineering reagents. In addition to altering the host genome, these methods can target pathogens to engineer molecular immunity. Indeed, recent studies have shown that clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated 9 (Cas9) systems that target the genomes of DNA viruses can interfere with viral activity and limit viral symptoms in planta, demonstrating the utility of this system for engineering molecular immunity in plants. CRISPR/Cas9 can efficiently target single and multiple viral infections and confer plant immunity. Here, we discuss the use of site-specific nucleases to engineer molecular immunity against DNA and RNA viruses in plants. We also explore how to address the potential challenges encountered when producing plants with engineered resistance to single and mixed viral infections.

  19. Engineering Molecular Immunity Against Plant Viruses

    KAUST Repository

    Zaidi, Syed Shan-e-Ali; Tashkandi, Manal; Mahfouz, Magdy M.

    2017-01-01

    Genomic engineering has been used to precisely alter eukaryotic genomes at the single-base level for targeted gene editing, replacement, fusion, and mutagenesis, and plant viruses such as Tobacco rattle virus have been developed into efficient vectors for delivering genome-engineering reagents. In addition to altering the host genome, these methods can target pathogens to engineer molecular immunity. Indeed, recent studies have shown that clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated 9 (Cas9) systems that target the genomes of DNA viruses can interfere with viral activity and limit viral symptoms in planta, demonstrating the utility of this system for engineering molecular immunity in plants. CRISPR/Cas9 can efficiently target single and multiple viral infections and confer plant immunity. Here, we discuss the use of site-specific nucleases to engineer molecular immunity against DNA and RNA viruses in plants. We also explore how to address the potential challenges encountered when producing plants with engineered resistance to single and mixed viral infections.

  20. Hanford Waste Vitrification Plant technology progress

    International Nuclear Information System (INIS)

    Wolfe, B.A.; Scott, J.L.; Allen, C.R.

    1989-10-01

    The Hanford Waste Vitrification Plant (HWVP) is currently being designed to safely process and temporarily store immobilized defense liquid high-level wastes from the Hanford Site. These wastes will be immobilized in a borosilicate glass waste form in the HWVP and stored onsite until a qualified geologic waste repository is ready for permanent disposal. Because of the diversity of wastes to be disposed of, specific technical issues are being addressed so that the plant can be designed and operated to produce a waste form that meets the requirements for permanent disposal in a geologic repository. This paper reports the progress to date in addressing these issues. 2 figs., 3 tabs

  1. Plant Translation Factors and Virus Resistance

    Directory of Open Access Journals (Sweden)

    Hélène Sanfaçon

    2015-06-01

    Full Text Available Plant viruses recruit cellular translation factors not only to translate their viral RNAs but also to regulate their replication and potentiate their local and systemic movement. Because of the virus dependence on cellular translation factors, it is perhaps not surprising that many natural plant recessive resistance genes have been mapped to mutations of translation initiation factors eIF4E and eIF4G or their isoforms, eIFiso4E and eIFiso4G. The partial functional redundancy of these isoforms allows specific mutation or knock-down of one isoform to provide virus resistance without hindering the general health of the plant. New possible targets for antiviral strategies have also been identified following the characterization of other plant translation factors (eIF4A-like helicases, eIF3, eEF1A and eEF1B that specifically interact with viral RNAs and proteins and regulate various aspects of the infection cycle. Emerging evidence that translation repression operates as an alternative antiviral RNA silencing mechanism is also discussed. Understanding the mechanisms that control the development of natural viral resistance and the emergence of virulent isolates in response to these plant defense responses will provide the basis for the selection of new sources of resistance and for the intelligent design of engineered resistance that is broad-spectrum and durable.

  2. 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 ...

  3. Comparative Infection Progress Analysis of Lettuce big-vein virus and Mirafiori lettuce virus in Lettuce Crops by Developed Molecular Diagnosis Techniques.

    Science.gov (United States)

    Navarro, Jose A; Botella, Francisco; Maruhenda, Antonio; Sastre, Pedro; Sánchez-Pina, M Amelia; Pallas, Vicente

    2004-05-01

    ABSTRACT Nonisotopic molecular dot blot hybridization technique and multiplex reverse transcription-polymerase chain reaction assay for the specific detection of Lettuce big-vein virus (LBVV) and Mirafiori lettuce virus (MiLV) in lettuce tissue were developed. Both procedures were suitable for the specific detection of both viruses in a range of naturally infected lettuce plants from various Spanish production areas and seven different cultivars. The study of the distribution of both viruses in the plant revealed that the highest concentration of LBVV and MiLV occurred in roots and old leaves, respectively. LBVV infection progress in a lettuce production area was faster than that observed for MiLV. In spite of different rates of virus infection progress, most lettuce plants became infected with both viruses about 100 days posttransplant. The appearance of both viruses in lettuce crops was preceded by a peak in the concentration of resting spores and zoosporangia of the fungus vector Olpidium brassicae in lettuce roots.

  4. Ecosystem simplification, biodiversity loss and plant virus emergence.

    Science.gov (United States)

    Roossinck, Marilyn J; García-Arenal, Fernando

    2015-02-01

    Plant viruses can emerge into crops from wild plant hosts, or conversely from domestic (crop) plants into wild hosts. Changes in ecosystems, including loss of biodiversity and increases in managed croplands, can impact the emergence of plant virus disease. Although data are limited, in general the loss of biodiversity is thought to contribute to disease emergence. More in-depth studies have been done for human viruses, but studies with plant viruses suggest similar patterns, and indicate that simplification of ecosystems through increased human management may increase the emergence of viral diseases in crops. Copyright © 2015 Elsevier B.V. All rights reserved.

  5. Sensitive radioimmunosorbent assay for the detection of plant viruses. [Cauliflower mosaic virus, lettuce mosaic virus

    Energy Technology Data Exchange (ETDEWEB)

    Ghabrial, S A; Shepherd, R J [Kentucky Univ., Lexington (USA); California Univ., Davis (USA))

    1980-06-01

    A simple and highly sensitive radioimmunosorbent assay (RISA) for the detection of plant viruses is described. The RISA procedure is a microplate method based on the principle of 'double-antibody sandwich' and follows essentially the protocol of the enzyme-linked immunosorbent assay (ELISA) (Clark and Adams, 1977), with the exception that /sup 125/I-labelled ..gamma..-globulin is substituted for the ..gamma..-globulin enzyme conjugate; the bound /sup 125/I-..gamma..-globulin is dissociated by acidification from the double-antibody sandwich. The radioactivity is proportional to virus concentration, and cauliflower mosaic virus (CaMV) and lettuce mosaic virus (LMV) could be detected at concentrations as low as 5 and 2 ng/ml, respectively. Direct evidence of the adverse effects of conjugation with enzyme on the binding abilities of antibodies is presented. The RISA procedure should prove valuable with viruses for which the ELISA values are too low to be dependable.

  6. Plant RNA binding proteins for control of RNA virus infection

    Directory of Open Access Journals (Sweden)

    Sung Un eHuh

    2013-12-01

    Full Text Available Plant RNA viruses have effective strategies to infect host plants through either direct or indirect interactions with various host proteins, thus suppressing the host immune system. When plant RNA viruses enter host cells exposed RNAs of viruses are recognized by the host immune system through processes such as siRNA-dependent silencing. Interestingly, some host RNA binding proteins have been involved in the inhibition of RNA virus replication, movement, and translation through RNA-specific binding. Host plants intensively use RNA binding proteins for defense against viral infections in nature. In this mini review, we will summarize the function of some host RNA binding proteins which act in a sequence-specific binding manner to the infecting virus RNA. It is important to understand how plants effectively suppresses RNA virus infections via RNA binding proteins, and this defense system can be potentially developed as a synthetic virus defense strategy for use in crop engineering.

  7. Infection of potato mesophyll protoplasts with five plant viruses.

    Science.gov (United States)

    Barker, H; Harrison, B D

    1982-12-01

    Methods are described for preparing potato mesophyll protoplasts that are suitable for infection with inocula of virus nucleoprotein or RNA. The protoplasts could be infected with four sap-transmissible viruses (tobacco mosaic, tobacco rattle, tobacco ringspot and tomato black ring viruses) and with potato leafroll virus, which is not saptransmissible. No differences were observed in ability to infect protoplasts with potato leafroll virus strains differing either in virulence in intact plants or in aphid transmissibility.

  8. Phomopsis longicolla RNA virus 1 - Novel virus at the edge of myco- and plant viruses.

    Science.gov (United States)

    Hrabáková, Lenka; Koloniuk, Igor; Petrzik, Karel

    2017-06-01

    The complete nucleotide sequence of a new RNA mycovirus in the KY isolate of Phomopsis longicolla Hobbs 1985 and its protoplasts subcultures p5, p9, and ME711 was discovered. The virus, provisionally named Phomopsis longicolla RNA virus 1 (PlRV1), was localized in mitochondria and was determined to have a genome 2822 nucleotides long. A single open reading frame could be translated in silico by both standard and mitochondrial genetic codes into a product featuring conservative domains for an RNA-dependent RNA polymerase (RdRp). The RdRp of PlRV1 has no counterpart among mycoviruses, but it is about 30% identical with the RdRp of plant ourmiaviruses. Recently, new mycoviruses related to plant ourmiaviruses and forming one clade with PlRV1 have been discovered. This separate clade could represent the crucial link between plant and fungal viruses. Copyright © 2017 Elsevier Inc. All rights reserved.

  9. AGO2: a new Argonaute compromising plant virus accumulation

    Directory of Open Access Journals (Sweden)

    Veria Y Alvarado

    2012-01-01

    Full Text Available Plant viruses use several strategies to transport their nucleic acid genomes throughout the plants. Regardless of the movement mechanism, a universal major block to uninterrupted viral trafficking is the induction of antiviral silencing that degrades viral RNA. To counteract this defense, viruses encode suppressors that block certain steps in the RNA silencing pathway, and consequently these proteins allow viral spread to proceed. There is a constant battle between plants and viruses and sometimes viruses will succeed and invade the plants and in other cases the RNA silencing mechanism will override the virus. A key role in the silencing versus suppression conflict between plants and viruses is played by one or more members of the ARGONAUTE protein (AGO family encoded by plants. Here we review the mechanisms and effects of antiviral silencing with an emphasis on the contribution of AGOs, especially the recently discovered role of AGO2.

  10. Progressive outer retinal necrosis: manifestation of human immunodeficiency virus infection.

    Science.gov (United States)

    Lo, Phey Feng; Lim, Rongxuan; Antonakis, Serafeim N; Almeida, Goncalo C

    2015-05-06

    We present the case of a 54-year-old man who developed progressive outer retinal necrosis (PORN) as an initial manifestation of HIV infection without any significant risk factors for infection with HIV. PORN is usually found as a manifestation of known AIDS late in the disease. Our patient presented with transient visual loss followed by decrease in visual acuity and facial rash. Subsequent investigation revealed anterior chamber tap positive for varicella zoster virus (VZV), as well as HIV positivity, with an initial CD4 count of 48 cells/µL. Systemic and intravitreal antivirals against VZV, and highly active antiretroviral therapy against HIV were started, which halted further progression of retinal necrosis. This case highlights the importance of suspecting PORN where there is a rapidly progressive retinitis, and also testing the patient for HIV, so appropriate treatment can be started. 2015 BMJ Publishing Group Ltd.

  11. A proposal to rationalize within-species plant virus nomenclature: benefits and implications of inaction.

    Science.gov (United States)

    Jones, Roger A C; Kehoe, Monica A

    2016-07-01

    Current approaches used to name within-species, plant virus phylogenetic groups are often misleading and illogical. They involve names based on biological properties, sequence differences and geographical, country or place-association designations, or any combination of these. This type of nomenclature is becoming increasingly unsustainable as numbers of sequences of the same virus from new host species and different parts of the world increase. Moreover, this increase is accelerating as world trade and agriculture expand, and climate change progresses. Serious consequences for virus research and disease management might arise from incorrect assumptions made when current within-species phylogenetic group names incorrectly identify properties of group members. This could result in development of molecular tools that incorrectly target dangerous virus strains, potentially leading to unjustified impediments to international trade or failure to prevent such strains being introduced to countries, regions or continents formerly free of them. Dangerous strains might be missed or misdiagnosed by diagnostic laboratories and monitoring programs, and new cultivars with incorrect strain-specific resistances released. Incorrect deductions are possible during phylogenetic analysis of plant virus sequences and errors from strain misidentification during molecular and biological virus research activities. A nomenclature system for within-species plant virus phylogenetic group names is needed which avoids such problems. We suggest replacing all other naming approaches with Latinized numerals, restricting biologically based names only to biological strains and removing geographically based names altogether. Our recommendations have implications for biosecurity authorities, diagnostic laboratories, disease-management programs, plant breeders and researchers.

  12. Editing plants for virus resistance using CRISPR-Cas.

    Science.gov (United States)

    Green, J C; Hu, J S

    This minireview summarizes recent advancements using the clustered regularly interspaced palindromic repeats-associated nuclease systems (CRISPR-Cas) derived from prokaryotes to breed plants resistant to DNA and RNA viruses. The CRISPR-Cas system represents a powerful tool able to edit and insert novel traits into plants precisely at chosen loci offering enormous advantages to classical breeding. Approaches to engineering plant virus resistance in both transgenic and non-transgenic plants are discussed. Iterations of the CRISPR-Cas system, FnCas9 and C2c2 capable of editing RNA in eukaryotic cells offer a particular advantage for providing resistance to RNA viruses which represent the great majority of known plant viruses. Scientists have obtained conflicting results using gene silencing technology to produce transgenic plants resistant to geminiviruses. CRISPR-Cas systems engineered in plants to target geminiviruses have consistently reduced virus accumulation providing increased resistance to virus infection. CRISPR-Cas may provide novel and reliable approaches to control geminiviruses and other ssDNA viruses such as Banana bunchy top virus (BBTV).

  13. Three-Dimensional Architecture and Biogenesis of Membrane Structures Associated with Plant Virus Replication

    Directory of Open Access Journals (Sweden)

    Xuejiao Jin

    2018-01-01

    Full Text Available Positive-sense (+ RNA viruses represent the most abundant group of viruses and are dependent on the host cell machinery to replicate. One remarkable feature that occurs after (+ RNA virus entry into cells is the remodeling of host endomembranes, leading to the formation of viral replication factories. Recently, rapid progress in three-dimensional (3D imaging technologies, such as electron tomography (ET and focused ion beam-scanning electron microscopy (FIB-SEM, has enabled researchers to visualize the novel membrane structures induced by viruses at high resolution. These 3D imaging technologies provide new mechanistic insights into the viral infection cycle. In this review, we summarize the latest reports on the cellular remodeling that occurs during plant virus infection; in particular, we focus on studies that provide 3D architectural information on viral replication factories. We also outline the mechanisms underlying the formation of these membranous structures and discuss possible future research directions.

  14. Alteration of cell cycle progression by Sindbis virus infection

    Energy Technology Data Exchange (ETDEWEB)

    Yi, Ruirong; Saito, Kengo [Department of Molecular Virology, Graduate School of Medicine, Chiba University Graduate School of Medicine, 1-8-1 Inohana, Chiba 260-8670 (Japan); Isegawa, Naohisa [Laboratory Animal Center, Graduate School of Medicine, Chiba University Graduate School of Medicine, 1-8-1 Inohana, Chiba 260-8670 (Japan); Shirasawa, Hiroshi, E-mail: sirasawa@faculty.chiba-u.jp [Department of Molecular Virology, Graduate School of Medicine, Chiba University Graduate School of Medicine, 1-8-1 Inohana, Chiba 260-8670 (Japan)

    2015-07-10

    We examined the impact of Sindbis virus (SINV) infection on cell cycle progression in a cancer cell line, HeLa, and a non-cancerous cell line, Vero. Cell cycle analyses showed that SINV infection is able to alter the cell cycle progression in both HeLa and Vero cells, but differently, especially during the early stage of infection. SINV infection affected the expression of several cell cycle regulators (CDK4, CDK6, cyclin E, p21, cyclin A and cyclin B) in HeLa cells and caused HeLa cells to accumulate in S phase during the early stage of infection. Monitoring SINV replication in HeLa and Vero cells expressing cell cycle indicators revealed that SINV which infected HeLa cells during G{sub 1} phase preferred to proliferate during S/G{sub 2} phase, and the average time interval for viral replication was significantly shorter in both HeLa and Vero cells infected during G{sub 1} phase than in cells infected during S/G{sub 2} phase. - Highlights: • SINV infection was able to alter the cell cycle progression of infected cancer cells. • SINV infection can affect the expression of cell cycle regulators. • SINV infection exhibited a preference for the timing of viral replication among the cell cycle phases.

  15. Alteration of cell cycle progression by Sindbis virus infection

    International Nuclear Information System (INIS)

    Yi, Ruirong; Saito, Kengo; Isegawa, Naohisa; Shirasawa, Hiroshi

    2015-01-01

    We examined the impact of Sindbis virus (SINV) infection on cell cycle progression in a cancer cell line, HeLa, and a non-cancerous cell line, Vero. Cell cycle analyses showed that SINV infection is able to alter the cell cycle progression in both HeLa and Vero cells, but differently, especially during the early stage of infection. SINV infection affected the expression of several cell cycle regulators (CDK4, CDK6, cyclin E, p21, cyclin A and cyclin B) in HeLa cells and caused HeLa cells to accumulate in S phase during the early stage of infection. Monitoring SINV replication in HeLa and Vero cells expressing cell cycle indicators revealed that SINV which infected HeLa cells during G 1 phase preferred to proliferate during S/G 2 phase, and the average time interval for viral replication was significantly shorter in both HeLa and Vero cells infected during G 1 phase than in cells infected during S/G 2 phase. - Highlights: • SINV infection was able to alter the cell cycle progression of infected cancer cells. • SINV infection can affect the expression of cell cycle regulators. • SINV infection exhibited a preference for the timing of viral replication among the cell cycle phases

  16. Pepino Mosaic Virus: a serious threat to tomato plants worldwide

    Directory of Open Access Journals (Sweden)

    Imane BIBI

    2017-09-01

    Full Text Available omato (Solanum lycopersicum is one of the widely grown crops worldwide. It is consumed in various forms and has excellent nutritional values. Presently, this crop is facing a serious threat to its yield and survival because of a potexvirus infection. One of the potexvirus species hampering tomato productions worldwide is Pepino mosaic virus (PepMV. This emerging virus is one of the most destructive plant diseases destroying tomato crops globally. It has spread to many countries worldwide including France, Italy, the UK, Poland, Belgium, the USA, Canada and China. PepMV genome consists of a positive-sense, single-stranded RNA molecule, approximately 6.4 kb in length. The genomic RNA contains five open reading frames (ORFs encoding for the coat protein (CP, the putative viral polymerase (RdRp and the triple gene block (TGB proteins. PepMV is efficiently transmitted mechanically. In other studies, seed transmission has been demonstrated. This article provides an overview of PepMV symptoms, transmission, different strains of PepMV, its genome organization and strategies employed for controlling it. The knowledge about the recent progress in the study of PepMV would help develop novel strategies for its control in agriculture.

  17. Plant conservation progress in the United States

    Science.gov (United States)

    Kayri Havens; Andrea Kramer; Ed. Guerrant

    2017-01-01

    Effective national plant conservation has several basic needs, including: 1) accessible, up-to-date information on species distribution and rarity; 2) research and management capacity to mitigate the impact of threats that make plants rare; 3) effective networks for conserving species in situ and ex situ; 4) education and training to make sure the right people are...

  18. Negative-strand RNA viruses: The plant-infecting counterparts

    NARCIS (Netherlands)

    Kormelink, R.J.M.; Garcia, M.L.; Goodin, M.; Sasaya, T.; Haenni, A.L.

    2011-01-01

    While a large number of negative-strand (-)RNA viruses infect animals and humans, a relative small number have plants as their primary host. Some of these have been classified within families together with animal/human infecting viruses due to similarities in particle morphology and genome

  19. Remediation Using Plants and Plant Enzymes: A Progress Report

    National Research Council Canada - National Science Library

    1995-01-01

    .... In every case, the sources are plants growing near the sediment. The use of plants for remediation of hazardous materials such as TNT or other munitions like RDX and HMX has led to a new approach to remediation-- phytoremediation...

  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. Quantifying progress toward a conservation assessment for all plants.

    Science.gov (United States)

    Bachman, Steven P; Nic Lughadha, Eimear M; Rivers, Malin C

    2018-06-01

    The Global Strategy for Plant Conservation (GSPC) set an ambitious target to achieve a conservation assessment for all known plant species by 2020. We consolidated digitally available plant conservation assessments and reconciled their scientific names and assessment status to predefined standards to provide a quantitative measure of progress toward this target. The 241,919 plant conservation assessments generated represent 111,824 accepted land plant species (vascular plants and bryophytes, not algae). At least 73,081 and up to 90,321 species have been assessed at the global scale, representing 21-26% of known plant species. Of these plant species, at least 27,148 and up to 32,542 are threatened. Eighty plant families, including some of the largest, such as Asteraceae, Orchidaceae, and Rubiaceae, are underassessed and should be the focus of assessment effort if the GSPC target is to be met by 2020. Our data set is accessible online (ThreatSearch) and is a baseline that can be used to directly support other GSPC targets and plant conservation action. Although around one-quarter of a million plant assessments have been compiled, the majority of plants are still unassessed. The challenge now is to build on this progress and redouble efforts to document conservation status of unassessed plants to better inform conservation decisions and conserve the most threatened species. © 2017 The Authors. Conservation Biology published by Wiley Periodicals, Inc. on behalf of Society for Conservation Biology.

  2. Characterization of a siberian virus isolated from a patient with progressive chronic tick-borne encephalitis.

    Science.gov (United States)

    Gritsun, T S; Frolova, T V; Zhankov, A I; Armesto, M; Turner, S L; Frolova, M P; Pogodina, V V; Lashkevich, V A; Gould, E A

    2003-01-01

    A strain of Tick-borne encephalitis virus designated Zausaev (Za) was isolated in Siberia from a patient who died of a progressive (2-year) form of tick-borne encephalitis 10 years after being bitten by a tick. The complete genomic sequence of this virus was determined, and an attempt was made to correlate the sequence with the biological characteristics of the virus. Phylogenetic analysis demonstrated that this virus belongs to the Siberian subtype of Tick-borne encephalitis virus. Comparison of Za virus with two related viruses, a Far Eastern isolate, Sofjin, and a Siberian isolate, Vasilchenko, revealed differences among the three viruses in pathogenicity for Syrian hamsters, cytopathogenicity for PS cells, plaque morphology, and the electrophoretic profiles of virus-specific nonstructural proteins. Comparative amino acid alignments revealed 10 individual amino acid substitutions in the Za virus polyprotein sequence that were different from those of other tick-borne flaviviruses. Notably, the dimeric form of the Za virus NS1 protein migrated in polyacrylamide gels as a heterogeneous group of molecules with a significantly higher electrophoretic mobility than those of the Sofjin and Vasilchenko viruses. Two amino acid substitutions, T(277)-->V and E(279)-->G, within the NS1 dimerization domain are probably responsible for the altered oligomerization of Za virus NS1. These studies suggest that the patient from whom Za virus was isolated died due to increased pathogenicity of the latent virus following spontaneous mutagenesis.

  3. Viruses that enhance the aethetics of some ornamental plants: beauty or beast?

    Science.gov (United States)

    Although most viruses that infect plants cause diseases that are detrimental to the plant, there are some instances in which infections by mild viral strains of a virus have been used to protect the plant against severe strains of the same virus. There are other viruses that can cause desirable effe...

  4. 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 ...

  5. A sensitive radioimmunosorbent assay for the detection of plant viruses

    International Nuclear Information System (INIS)

    Ghabrial, S.A.; Shepherd, R.J.

    1980-01-01

    A simple and highly sensitive radioimmunosorbent assay (RISA) for the detection of plant viruses is described. The RISA procedure is a microplate method based on the principle of 'double-antibody sandwich' and follows essentially the protocol of the enzyme-linked immunosorbent assay (ELISA) (Clark and Adams, 1977), with the exception that 125 I-labelled γ-globulin is substituted for the γ-globulin enzyme conjugate; the bound 125 I-γ-globulin is dissociated by acidification from the double-antibody sandwich. The radioactivity is proportional to virus concentration, and cauliflower mosaic virus (CaMV) and lettuce mosaic virus (LMV) could be detected at concentrations as low as 5 and 2 ng/ml, respectively. Direct evidence of the adverse effects of conjugation with enzyme on the binding abilities of antibodies is presented. The RISA procedure should prove valuable with viruses for which the ELISA values are too low to be dependable. (author)

  6. Negative-strand RNA viruses: the plant-infecting counterparts.

    Science.gov (United States)

    Kormelink, Richard; Garcia, Maria Laura; Goodin, Michael; Sasaya, Takahide; Haenni, Anne-Lise

    2011-12-01

    While a large number of negative-strand (-)RNA viruses infect animals and humans, a relative small number have plants as their primary host. Some of these have been classified within families together with animal/human infecting viruses due to similarities in particle morphology and genome organization, while others have just recently been/or are still classified in floating genera. In most cases, at least two striking differences can still be discerned between the animal/human-infecting viruses and their plant-infecting counterparts which for the latter relate to their adaptation to plants as hosts. The first one is the capacity to modify plasmodesmata to facilitate systemic spread of infectious viral entities throughout the plant host. The second one is the capacity to counteract RNA interference (RNAi, also referred to as RNA silencing), the innate antiviral defence system of plants and insects. In this review an overview will be presented on the negative-strand RNA plant viruses classified within the families Bunyaviridae, Rhabdoviridae, Ophioviridae and floating genera Tenuivirus and Varicosavirus. Genetic differences with the animal-infecting counterparts and their evolutionary descendants will be described in light of the above processes. Copyright © 2011 Elsevier B.V. All rights reserved.

  7. Gravisensitivity of various host plant -virus systems in simulated microgravity

    Science.gov (United States)

    Mishchenko, Lidiya; Taran, Oksana; Gordejchyk, Olga

    In spite of considerable achievements in the study of gravity effects on plant development, some issues of gravitropism, like species-specificity and gravitation response remain unclear. The so-lution of such problems is connected with the aspects of life supply, in piloted space expeditions. The role of microgravity remains practically unstudied in the development of relations in the system host plant-virus, which are important for biotechnologies in crop production. It is ev-ident that the conditions of space flight can act as stressors, and the stress inducted by them favors the reactivation of latest herpes viruses in humans (satish et al., 2009) Viral infections of plants, which also can be in a latest state at certain stages of plant organism development, cause great damage to the growth and development of a host plant. Space flight conditions may cause both reactivation of latent viral infection in plants and its elimination, as it has been found by us for the system WSMW -wheat (Mishchenko et al., 2004). Our further research activities were concentrated on the identification of gravisensitivity in the system virus -potato plant to find out whether there was any species -related specificity of the reaction. In our research we used potato plants of Krymska Rosa, Zhuravushka, Agave, Belarosa, Kupalinka, and Zdubytok varieties. Simulated microgravity was ensured by clinostats KG-8 and Cycle -2. Gravisensitiv-ity has been studied the systems including PVX, PVM and PVY. Virus concentrations have been determined by ELISA using LOEWE reagents (placecountry-regionGermany). Virus iden-tification by morphological features were done by electron microscopy. For the system PVX -potato plant, we found the reduction in virus antigens content with prolonged clinostating. On the 18th day of cultivation, the plants showed a high level of X-virus antigen content on both stationary (control) and clinostated variants. On 36th and 47th day, depending plant variety, clinostated

  8. Progress and prospects: foamy virus vectors enter a new age.

    Science.gov (United States)

    Erlwein, O; McClure, M O

    2010-12-01

    Foamy viruses, distantly related to the major subfamily of Retroviruses, Orthoretroviruses that include oncoviruses (for example, murine leukemia virus (MLV)) and lentiviruses (human immunodeficiency virus (HIV)), are endemic in mammalian species, but not in human populations. Humans infected by accidental or occupational exposure remain well. The virus is not transmitted to others, nor is it associated with any disease. These features added to its broad host range, efficient transduction of progenitor cells and an integration profile less likely to induce insertional mutagenesis, make these viruses attractive as vectors. Long-term reversal of disease phenotype in dogs with the genetic defect, leukocyte adhesion deficiency, by foamy virus vector therapy strengthens the case for their clinical exploitation.

  9. Herbivore arthropods benefit from vectoring plant viruses

    NARCIS (Netherlands)

    Belliure, B.; Janssen, A.; Maris, P.C.; Peters, D.; Sabelis, M.W.

    2005-01-01

    Plants infected with pathogens often attract the pathogens' vectors, but it is not clear if this is advantageous to the vectors. We therefore quantified the direct and indirect (through the host plant) effects of a pathogen on its vector. A positive direct effect of the plant-pathogenic Tomato

  10. Signal validation in nuclear power plants: Progress report No. 3

    International Nuclear Information System (INIS)

    Kerlin, T.W.; Upadhyaya, B.R.

    1987-01-01

    This report summarizes the progress in the Signal Validation Project. Specifically, the advances made in several of the modules have been described. Some of these modules are now ready for preliminary implementation using plant operational data. Arrangements with Northeast Utilities Service Company (NUSCO) for transferring several sets of plant operational data from Millstone-3 PWR have been made in preparation for this phase of the project

  11. The research progress on plant mutant germplasm resources in China

    International Nuclear Information System (INIS)

    He Cexi; Ji Linzhen; Zhao Shirong

    1991-07-01

    Mutants induced by nuclear radiation or other mutagens are new artificial germplasm resources. Some mutants have been applied in plant breeding and great achievements have been reached. The status and progress on the collection, identification and utilization of mutants in China are introduced. A proposal for developing mutant germplasm resources with good agronomic characters is suggested

  12. Ebolavirus Vaccines: Progress in the Fight Against Ebola Virus Disease.

    Science.gov (United States)

    Wu, Xiao-Xin; Yao, Hang-Ping; Wu, Nan-Ping; Gao, Hai-Nv; Wu, Hai-Bo; Jin, Chang-Zhong; Lu, Xiang-Yun; Xie, Tian-Shen; Li, Lan-Juan

    2015-01-01

    Ebolaviruses are highly infectious pathogens that cause lethal Ebola virus disease (EVD) in humans and non-human primates (NHPs). Due to their high pathogenicity and transmissibility, as well as the potential to be misused as a bioterrorism agent, ebolaviruses would threaten the health of global populations if not controlled. In this review, we describe the origin and structure of ebolaviruses and the development of vaccines from the beginning of the 1980s, including conventional ebolavirus vaccines, DNA vaccines, Ebola virus-like particles (VLPs), vaccinia virus-based vaccines, Venezuelan equine encephalitis virus (VEEV)-like replicon particles, Kunjin virus-based vaccine, recombinant Zaire Ebolavirusx2206;VP30, recombinant cytomegalovirus (CMV)-based vaccines, recombinant rabies virus (RABV)-based vaccines, recombinant paramyxovirus-based vaccines, adenovirus-based vaccines and vesicular stomatitis virus (VSV)-based vaccines. No licensed vaccine or specific treatment is currently available to counteract ebolavirus infection, although DNA plasmids and several viral vector approaches have been evaluated as promising vaccine platforms. These vaccine candidates have been confirmed to be successful in protecting NHPs against lethal infection. Moreover, these vaccine candidates were successfully advanced to clinical trials. The present review provides an update of the current research on Ebola vaccines, with the aim of providing an overview on current prospects in the fight against EVD. © 2015 The Author(s) Published by S. Karger AG, Basel.

  13. Ebolavirus Vaccines: Progress in the Fight Against Ebola Virus Disease

    Directory of Open Access Journals (Sweden)

    Xiao-Xin Wu

    2015-11-01

    Full Text Available Ebolaviruses are highly infectious pathogens that cause lethal Ebola virus disease (EVD in humans and non-human primates (NHPs. Due to their high pathogenicity and transmissibility, as well as the potential to be misused as a bioterrorism agent, ebolaviruses would threaten the health of global populations if not controlled. In this review, we describe the origin and structure of ebolaviruses and the development of vaccines from the beginning of the 1980s, including conventional ebolavirus vaccines, DNA vaccines, Ebola virus-like particles (VLPs, vaccinia virus-based vaccines, Venezuelan equine encephalitis virus (VEEV-like replicon particles, Kunjin virus-based vaccine, recombinant Zaire Ebolavirus∆VP30, recombinant cytomegalovirus (CMV-based vaccines, recombinant rabies virus (RABV-based vaccines, recombinant paramyxovirus-based vaccines, adenovirus-based vaccines and vesicular stomatitis virus (VSV-based vaccines. No licensed vaccine or specific treatment is currently available to counteract ebolavirus infection, although DNA plasmids and several viral vector approaches have been evaluated as promising vaccine platforms. These vaccine candidates have been confirmed to be successful in protecting NHPs against lethal infection. Moreover, these vaccine candidates were successfully advanced to clinical trials. The present review provides an update of the current research on Ebola vaccines, with the aim of providing an overview on current prospects in the fight against EVD.

  14. [Effects of plant viruses on vector and non-vector herbivorous arthropods and their natural enemies: a mini review].

    Science.gov (United States)

    He, Xiao-Chan; Xu, Hong-Xing; Zhou, Xiao-Jun; Zheng, Xu-Song; Sun, Yu-Jian; Yang, Ya-Jun; Tian, Jun-Ce; Lü, Zhong-Xian

    2014-05-01

    Plant viruses transmitted by arthropods, as an important biotic factor, may not only directly affect the yield and quality of host plants, and development, physiological characteristics and ecological performances of their vector arthropods, but also directly or indirectly affect the non-vector herbivorous arthropods and their natural enemies in the same ecosystem, thereby causing influences to the whole agro-ecosystem. This paper reviewed the progress on the effects of plant viruses on herbivorous arthropods, including vector and non-vector, and their natural enemies, and on their ecological mechanisms to provide a reference for optimizing the management of vector and non-vector arthropod populations and sustainable control of plant viruses in agro-ecosystem.

  15. Ficus septica plant extracts for treating Dengue virus in vitro

    Directory of Open Access Journals (Sweden)

    Nan-Chieh Huang

    2017-06-01

    Full Text Available Dengue virus types 1-4 (DENV-1-4 are positive-strand RNA viruses with an envelope that belongs to the Flaviviridae. DENV infection threatens human health worldwide. However, other than supportive treatments, no specific therapy is available for the infection. In order to discover novel medicine against DENV, we tested 59 crude extracts, without cytotoxicity, from 23 plants in vitro; immunofluorescence assay revealed that the methanol extracts of fruit, heartwood, leaves and stem from Ficus septica Burm. f. had a promising anti-DENV-1 and DENV-2 effect. However, infection with the non-envelope picornavirus, Aichi virus, was not inhibited by treatment with F. septica extracts. F. septica may be a candidate antiviral drug against an enveloped virus such as DENV.

  16. Understanding the Dengue Viruses and Progress towards Their Control

    Science.gov (United States)

    Gould, Ernest A.

    2013-01-01

    Traditionally, the four dengue virus serotypes have been associated with fever, rash, and the more severe forms, haemorrhagic fever and shock syndrome. As our knowledge as well as understanding of these viruses increases, we now recognise not only that they are causing increasing numbers of human infections but also that they may cause neurological and other clinical complications, with sequelae or fatal consequences. In this review we attempt to highlight some of these features in the context of dengue virus pathogenesis. We also examine some of the efforts currently underway to control this “scourge” of the tropical and subtropical world. PMID:23936833

  17. Plant materials program. Progress report, June 1980-May 1981

    International Nuclear Information System (INIS)

    Childs, W.; Cubicciotti, D.; Fox, M.; Giannuzzi, A.; Gilman, J.; Jones, R.; McIlree, A.

    1981-11-01

    This is the first annual progress report of the Plant Materials Subprogram, which was organized in May 1980 to address corrosion-related materials problems in light water reactors. The first section of the report provides an overview of plant materials problems which have a high impact on plant availability. These include pipe and pressure vessel cracking, condenser leakage, turbine disc cracking, and steam generator tube denting and cracking. The status and goals of research and development work related to each of these problems are reviewed briefly. Subsequent report sections provide more detailed reviews of significant progress in the relevant technical topic areas: intergranular stress corrosion cracking of austenitic stainless steels; environmentally-assisted cracking of carbon and low alloy steels; intergranular stress corrosion cracking of nickel-base alloys; and improved fabrication technology

  18. Plant Materials Program: progress June 1981 to May 1982

    International Nuclear Information System (INIS)

    Childs, W.; Cubicciotti, D.; Fox, M.; Giannuzzi, A.; Gilman, J.; Jones, R.

    1983-02-01

    This is the second annual progress report of the Plant Materials Subprogram, which was organized in May 1980 to address corrosion-related materials problems in light water reactors. The first section of the report provides an overview of plant materials problems which have a high impact on plant availability. These include pipe and pressure vessel cracking, condenser leakage, turbine disc cracking, steam geerator tube attack and cracking, and cracking of nickel alloy springs, beams and pins. The status and goals of research and development work related to each of these problems are reviewed briefly. Subsequent report sections provide more detailed reviews of significant progress in the relevant technical topic areas: intergranular stress corrosion cracking of austenitic stainless steels; environmentally-assisted cracking of carbon and low alloy steels; intergranular stress corrosion cracking of nickel-base alloys; and improved fabrication technology

  19. Plant Materials Program: progress June 1981-May 1982

    International Nuclear Information System (INIS)

    Childs, W.; Cubicciotti, D.; Fox, M.; Giannuzzi, A.; Gilman, J.; Jones, R.

    1983-02-01

    This is the second annual progress report of the Plant Materials Subprogram, which was organized in May 1980 to address corrosion-related materials problems in light water reactors. The first section of the report provides an overview of plant materials problems which have impact on plant availability. These include pipe and pressure vessel cracking, condenser leakage, turbine disc cracking, steam generator tube attack and cracking, and cracking of nickel alloy springs, beams and pins. The status and goals of research and development work related to each of these problems are reviewed briefly. Subsequent report sections provide more detailed reviews of significant progress in the relevant technical topic area: integranular stress corrosion cracking of austenitic stainless steels; environmentally-assisted cracking of carbon and low alloy steels; intergranular stress corrosion cracking of nickel-base alloys; and improved fabrication technology

  20. PROGRESSION OF LIVER FIBROSIS IN MONOINFECTED PATIENTS BY HEPATITIS C VIRUS AND COINFECTED BY HCV AND HUMAN IMMUNODEFICIENCY VIRUS

    Directory of Open Access Journals (Sweden)

    Cristiane Valle TOVO

    2013-03-01

    Full Text Available Context The progression of liver fibrosis in patients coinfected by hepatitis C virus and human immunodeficiency virus (HCV/HIV has been increasingly studied in the past decade. Studies made before the highly active antiretroviral therapy suggest that HIV can change the natural history of the HCV infection, leading to a faster progression of the liver fibrosis. Objective To evaluate and compare the fibrosis progression in two groups of patients (HCV/HIV coinfected and HCV monoinfected Methods Seventy patients HCV monoinfected and 26 patients HCV/HIV coinfected who had not undertaken HCV treatment and were submitted to serial percutaneous liver biopsies were retrospectively evaluated. There was no difference in the fibrosis progression between the two groups. Conclusion The fibrosis grade evolution was not worse in the coinfected patients. The immunosuppression absence and the shortest time period between the biopsies in the coinfected group are possible explanations.

  1. Sharka: how do plants respond to Plum pox virus infection?

    Science.gov (United States)

    Clemente-Moreno, María J; Hernández, José A; Diaz-Vivancos, Pedro

    2015-01-01

    Plum pox virus (PPV), the causal agent of sharka disease, is one of the most studied plant viruses, and major advances in detection techniques, genome characterization and organization, gene expression, transmission, and the description of candidate genes involved in PPV resistance have been described. However, information concerning the plant response to PPV infection is very scarce. In this review, we provide an updated summary of the research carried out to date in order to elucidate how plants cope with PPV infection and their response at different levels, including the physiological, biochemical, proteomic, and genetic levels. Knowledge about how plants respond to PPV infection can contribute to the development of new strategies to cope with this disease. Due to the fact that PPV induces an oxidative stress in plants, the bio-fortification of the antioxidative defences, by classical or biotechnological approaches, would be a useful tool to cope with PPV infection. Nevertheless, there are still some gaps in knowledge related to PPV-plant interaction that remain to be filled, such as the effect of PPV on the hormonal profile of the plant or on the plant metabolome. © The Author 2014. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  2. Production of Japanese Encephalitis Virus Antigens in Plants Using Bamboo Mosaic Virus-Based Vector

    Directory of Open Access Journals (Sweden)

    Tsung-Hsien Chen

    2017-05-01

    Full Text Available Japanese encephalitis virus (JEV is among the major threats to public health in Asia. For disease control and prevention, the efficient production of safe and effective vaccines against JEV is in urgent need. In this study, we produced a plant-made JEV vaccine candidate using a chimeric virus particle (CVP strategy based on bamboo mosaic virus (BaMV for epitope presentation. The chimeric virus, designated BJ2A, was constructed by fusing JEV envelope protein domain III (EDIII at the N-terminus of BaMV coat protein, with an insertion of the foot-and-mouth disease virus 2A peptide to facilitate the production of both unfused and epitope-presenting for efficient assembly of the CVP vaccine candidate. The strategy allowed stable maintenance of the fusion construct over long-term serial passages in plants. Immuno-electron microscopy examination and immunization assays revealed that BJ2A is able to present the EDIII epitope on the surface of the CVPs, which stimulated effective neutralizing antibodies against JEV infection in mice. This study demonstrates the efficient production of an effective CVP vaccine candidate against JEV in plants by the BaMV-based epitope presentation system.

  3. A century of plant virus management in the Salinas valley of California, 'East of Eden'.

    Science.gov (United States)

    Wisler, G C; Duffus, J E

    2000-11-01

    involves several cultural practices, but the use of resistant varieties is the most effective and is necessary where soils are infested. Rhizomania-resistant varieties are now available that perform almost as well as the non-resistant varieties under non-rhizomania conditions. Another soil-borne disease termed lettuce dieback, caused by a tomato bushy stunt-like tombusvirus, has become economically limiting to romaine and leaf lettuce varieties. The virus has no known vector and it seems to be moved through infested soil and water. Heavy rains in the past 4 years have caused flooding of the Salinas River and lettuce fields along the river have been affected severely by dieback. Studies are now in progress to characterize this new virus and identify sources of resistance. Agriculture in the Salinas Valley continues to grow and diversify, driven by demands for 'clean', high quality food by the American public and for export. The major aspects of plant virus control, including crop-free periods, breeding for resistance, elimination of inoculum sources, and vector control will continue to be vital to this expansion. Undoubtedly, the advances in crop production through genetic manipulation and advances in pest management through biological control will eventually become an important part of agricultural improvement.

  4. Plant RNA Regulatory Network and RNA Granules in Virus Infection

    Directory of Open Access Journals (Sweden)

    Kristiina Mäkinen

    2017-12-01

    Full Text Available Regulation of post-transcriptional gene expression on mRNA level in eukaryotic cells includes translocation, translation, translational repression, storage, mRNA decay, RNA silencing, and nonsense-mediated decay. These processes are associated with various RNA-binding proteins and cytoplasmic ribonucleoprotein complexes many of which are conserved across eukaryotes. Microscopically visible aggregations formed by ribonucleoprotein complexes are termed RNA granules. Stress granules where the translationally inactive mRNAs are stored and processing bodies where mRNA decay may occur present the most studied RNA granule types. Diverse RNP-granules are increasingly being assigned important roles in viral infections. Although the majority of the molecular level studies on the role of RNA granules in viral translation and replication have been conducted in mammalian systems, some studies link also plant virus infection to RNA granules. An increasing body of evidence indicates that plant viruses require components of stress granules and processing bodies for their replication and translation, but how extensively the cellular mRNA regulatory network is utilized by plant viruses has remained largely enigmatic. Antiviral RNA silencing, which is an important regulator of viral RNA stability and expression in plants, is commonly counteracted by viral suppressors of RNA silencing. Some of the RNA silencing suppressors localize to cellular RNA granules and have been proposed to carry out their suppression functions there. Moreover, plant nucleotide-binding leucine-rich repeat protein-mediated virus resistance has been linked to enhanced processing body formation and translational repression of viral RNA. Many interesting questions relate to how the pathways of antiviral RNA silencing leading to viral RNA degradation and/or repression of translation, suppression of RNA silencing and viral RNA translation converge in plants and how different RNA granules and

  5. Plant RNA Regulatory Network and RNA Granules in Virus Infection.

    Science.gov (United States)

    Mäkinen, Kristiina; Lõhmus, Andres; Pollari, Maija

    2017-01-01

    Regulation of post-transcriptional gene expression on mRNA level in eukaryotic cells includes translocation, translation, translational repression, storage, mRNA decay, RNA silencing, and nonsense-mediated decay. These processes are associated with various RNA-binding proteins and cytoplasmic ribonucleoprotein complexes many of which are conserved across eukaryotes. Microscopically visible aggregations formed by ribonucleoprotein complexes are termed RNA granules. Stress granules where the translationally inactive mRNAs are stored and processing bodies where mRNA decay may occur present the most studied RNA granule types. Diverse RNP-granules are increasingly being assigned important roles in viral infections. Although the majority of the molecular level studies on the role of RNA granules in viral translation and replication have been conducted in mammalian systems, some studies link also plant virus infection to RNA granules. An increasing body of evidence indicates that plant viruses require components of stress granules and processing bodies for their replication and translation, but how extensively the cellular mRNA regulatory network is utilized by plant viruses has remained largely enigmatic. Antiviral RNA silencing, which is an important regulator of viral RNA stability and expression in plants, is commonly counteracted by viral suppressors of RNA silencing. Some of the RNA silencing suppressors localize to cellular RNA granules and have been proposed to carry out their suppression functions there. Moreover, plant nucleotide-binding leucine-rich repeat protein-mediated virus resistance has been linked to enhanced processing body formation and translational repression of viral RNA. Many interesting questions relate to how the pathways of antiviral RNA silencing leading to viral RNA degradation and/or repression of translation, suppression of RNA silencing and viral RNA translation converge in plants and how different RNA granules and their individual

  6. Molecular characterization of a novel cryptic virus infecting pigeonpea plants.

    Directory of Open Access Journals (Sweden)

    Surender Kumar

    Full Text Available A new member of the genus Deltapartitivirus was identified containing three dsRNAs with an estimated size of 1.71, 1.49 and 1.43 kb. The dsRNAs were extracted from symptomless pigeonpea [Cajanus cajan (L. Millspaugh] plants cv. Erra Kandulu. This new virus with 4.64 kb genome was tentatively named Arhar cryptic virus-1 (ArCV-1. The genomic RNAs were amplified and characterized by sequence independent single primer amplification. The dsRNAs shared a highly conserved 16 nt 5' non-coding region (5'-GATAATGATCCAAGGA-3'. The largest dsRNA (dsRNA-1 was identified as the viral RNA dependent RNA polymerase (replicase, predicted to encode a putative 55.34 kDa protein (P1. The two other smaller dsRNAs (dsRNA-2 and dsRNA-3 predicted to encode for putative capsid proteins of 38.50kDa (P2 and 38.51kDa (P3, respectively. Phylogenetic analysis indicated that ArCV-1 formed a clade together with Fragaria chiloensis cryptic virus, Rosa multiflora cryptic virus and Rose cryptic virus-1, indicating that ArCV-1 could be a new member of the genus Deltapartitivirus. ArCV-1 3Dpol structure revealed several interesting features. The 3Dpol in its full-length shares structural similarities with members of the family Caliciviridaeand family Picornaviridae. In addition, fourth dsRNA molecule (dsRNA-2A, not related to ArCV-1 genome, was found in the same plant tissue. The dsRNA-2A (1.6 kb encodes a protein (P4, with a predicted size of 44.5 kDa. P4 shares similarity with coat protein genes of several cryptic viruses, in particular the bipartite cryptic viruses including Raphanus sativus cryptic virus-3. This is the first report of occurrence of a cryptic virus in pigeonpea plants.

  7. Progression of experimental chronic Aleutian mink disease virus infection

    DEFF Research Database (Denmark)

    Jensen, Trine Hammer; Chriél, Mariann; Hansen, Mette Sif

    2016-01-01

    Aleutian mink disease virus (AMDV) is found world-wide and has a major impact on mink health and welfare by decreasing reproduction and fur quality. In the majority of mink, the infection is subclinical and the diagnosis must be confirmed by serology or polymerase chain reaction (PCR). Increased ...

  8. Coevolution of a Persistent Plant Virus and Its Pepper Hosts.

    Science.gov (United States)

    Safari, Maliheh; Roossinck, Marilyn J

    2018-05-30

    There are many nonpathogenic viruses that are maintained in a persistent lifestyle in plants. Plant persistent viruses are widespread, replicating in their hosts for many generations. So far, Endornaviridae is the only family of plant persistent viruses with a single-stranded RNA genome, containing one large open reading frame. Bell pepper endornavirus (BPEV), Hot pepper endornavirus, Capsicum frutescens endornavirus 1 (CFEV 1) have been identified from peppers. Peppers are native to Central and South America and, as domesticated plants, human selection accelerated their evolution. We investigated the evolution of these endornaviruses in different peppers including Capsicum annuum, C. chacoense, C.chinense, C. frutescens, C.bacccutum, and C. pubescens using two fragments from the viral helicase (Hel) and RNA dependent RNA polymerase (RdRp) domains. In addition, using single nucleotide polymorphisms, we analyzed the pepper host populations and phylogenies. The endornaviruses phylogeny was correlated with its Capsicum species host. In this study, BPEV was limited to C. annuum species, and the RdRp and Hel phylogenies identified two clades that correlated with the host pungency. No C. annuum infected with CFEV 1 was found in this study, but the CFEV 1 RdRp fragment was recovered from C. chinense, C. frutescens, C. bacccutum, and C. pubescens. Hence, during pepper speciation, the ancestor of CFEV 1 may have evolved as a new endornavirus, BPEV, in C. annuum peppers.

  9. Phenotype Variation in Human Immunodeficiency virus Type 1 Transmission and Disease Progression

    Directory of Open Access Journals (Sweden)

    Mariangela Cavarelli

    2009-01-01

    Full Text Available Human immunodeficiency virus type I (HIV-1 infects target cells through interaction with the CD4 molecule and chemokine receptors, mainly CCR5 and CXCR4. Viral isolates can be phenotypically classified based on the co-receptor they utilize to infect target cells. Thus, R5 and X4 virus use respectively CCR5 and CXCR4, whereas R5X4 virus can use either CCR5 or CXCR4. This review describes the central role played by co-receptor expression and usage for HIV-1 cell tropism, transmission and pathogenesis. We discuss various hypotheses proposed to explain the preferential transmission of R5 viruses and the mechanisms driving the change of HIV-1 co-receptor usage in the course of infection. Recent insights in the intrinsic variability of R5 viruses and their role in influencing disease progression in both adults and children are also discussed.

  10. Phenotype variation in human immunodeficiency virus type 1 transmission and disease progression.

    Science.gov (United States)

    Cavarelli, Mariangela; Scarlatti, Gabriella

    2009-01-01

    Human immunodeficiency virus type I (HIV-1) infects target cells through interaction with the CD4 molecule and chemokine receptors, mainly CCR5 and CXCR4. Viral isolates can be phenotypically classified based on the co-receptor they utilize to infect target cells. Thus, R5 and X4 virus use respectively CCR5 and CXCR4, whereas R5X4 virus can use either CCR5 or CXCR4. This review describes the central role played by co-receptor expression and usage for HIV-1 cell tropism, transmission and pathogenesis. We discuss various hypotheses proposed to explain the preferential transmission of R5 viruses and the mechanisms driving the change of HIV-1 co-receptor usage in the course of infection. Recent insights in the intrinsic variability of R5 viruses and their role in influencing disease progression in both adults and children are also discussed.

  11. Is there a role for symbiotic bacteria in plant virus transmission?

    Science.gov (United States)

    During the process of circulative plant virus transmission by insect vectors, viruses interact with different insect vector tissues prior to transmission to a new host plant. An area of intense debate in the field is whether bacterial symbionts of insect vectors are involved in the virus transmissi...

  12. Micropropagation of tulip: production of virus-free stock plants.

    Science.gov (United States)

    Podwyszyńska, Małgorzata; Sochacki, Dariusz

    2010-01-01

    We describe here a new tulip micropropagation method based on the cyclic shoot multiplication in presence of the thidiazuron (TDZ), which enables the production of virus-free stock plants, speeds up breeding, and provides new genotypes for the market. In our novel protocol, cyclic shoot multiplication can be performed for 2-3 years by using TDZ instead of other cytokinins, as 6-benzylaminopurine (BAP) and N(6)-(-isopentyl)adenine (2iP). It makes possible to produce 500-2,000 microbulbs from one healthy plant. There are six main stages of tulip micropropagation. Stage 0 is the selection of true-to-type and virus-free plants, confirmed by ELISA. Fragments of flower stems isolated from bulbs are used as initial explants. Shoot multiplication is based on the regeneration of adventitious shoots, which are sub-cultured every 8 weeks. In the Stage 3, the specially prepared shoots are induced by low temperature treatment to form bulbs which finally develop on a sucrose-rich medium at 20 degrees C. Bulbs are then dried for 6 weeks and rooted in vivo. The number of multiplication subcultures should be limited to 5-10 cycles in order to lower the risk of mutation. Virus indexing should be repeated 3-4 times, at the initial stage and then during shoot multiplication. Genetic stability of micropropagated shoots can be confirmed using molecular markers.

  13. Biosecurity implications of new technology and discovery in plant virus research.

    Directory of Open Access Journals (Sweden)

    Robin MacDiarmid

    Full Text Available Human activity is causing new encounters between viruses and plants. Anthropogenic interventions include changing land use, decreasing biodiversity, trade, the introduction of new plant and vector species to native landscapes, and changing atmospheric and climatic conditions. The discovery of thousands of new viruses, especially those associated with healthy-appearing native plants, is shifting the paradigm for their role within the ecosystem from foe to friend. The cost of new plant virus incursions can be high and result in the loss of trade and/or production for short or extended periods. We present and justify three recommendations for plant biosecurity to improve communication about plant viruses, assist with the identification of viruses and their impacts, and protect the high economic, social, environmental, and cultural value of our respective nations' unique flora: 1 As part of the burden of proof, countries and jurisdictions should identify what pests already exist in, and which pests pose a risk to, their native flora; 2 Plant virus sequences not associated with a recognized virus infection are designated as "uncultured virus" and tentatively named using the host plant species of greatest known prevalence, the word "virus," a general location identifier, and a serial number; and 3 Invest in basic research to determine the ecology of known and new viruses with existing and potential new plant hosts and vectors and develop host-virus pathogenicity prediction tools. These recommendations have implications for researchers, risk analysts, biosecurity authorities, and policy makers at both a national and an international level.

  14. Method of inhibiting plant virus pathogen infections by crispr/cas9-mediated interference

    KAUST Repository

    Mahfouz, Magdy M.; Ali, Zahir

    2016-01-01

    A genetically modified tobacco plant or tomato plant resistant to at least one pathogenic geminiviridae virus species is provided. The plant comprises a heterologous CRISPR/Cas9 system and at least one heterologous nucleotide sequence

  15. The progress of mutation breeding for ornamental plants in China

    International Nuclear Information System (INIS)

    Jin Shouming

    1994-02-01

    In China, research on mutation breeding of ornamental plants was begun in the late 70's. In the past decade, about 40 plant species were tested, and hundreds of useful mutants were obtained. At least 63 mutant varieties have been produced, approved and released for cultivation in rose, chrysanthemum, canna, dahlia, bougainvillea and lotus. A rapid progress in methodology and technology of induced mutation breeding has been achieved, particularly in the selection of starting material, determination of suitable exposure and irradiation dose, expression and isolation of somatic mutation etc. In the future it is necessary to develop more plant species and mutation varieties to improve the mutation breeding method and to raise the economic benefit. Along with the development of China's economy and improvement of people's living standard more and more new varieties of ornamental plants will be required. In view of the good beginning, rich germplasm resource and favorable conditions, the prospect of mutation breeding for ornamental plants in China is very encouraging

  16. The Waste Treatment Plant, a Work in Progress

    International Nuclear Information System (INIS)

    Hamel, W. F. Jr.; Duncan, G. M.

    2006-01-01

    There are many challenges in the design and construction of Department of Energy's (DOE) Waste Treatment and Immobilization Plant (WTP) at the Hanford site. The plant is being built to process some 55 million gallons of radioactive waste from 177 underground tanks. Engineering and construction are progressing on this largest project in the DOE complex. This paper describes some of WTP's principal recent challenges and opportunities and how they are being addressed to minimize impact on the project, enhance the capabilities of the facilities, and reduce risk. A significant new development in 2005 was the need to account for higher seismic accelerations than originally specified for the facility structures and equipment. Efforts have centered on continuing design and construction with minimal risk, while the final seismic design spectra was developed. Other challenges include development of an alternative cesium ion exchange resin to minimize the risk from reliance on a single product, implementing advanced analytical techniques to improve laboratory performance, adopting a thinner walled high level waste (HLW) canister to reduce waste volume and mission duration, and commissioning a comprehensive external flowsheet review of the design, along with its underpinning technologies, and projected plant operability. These challenges make it clear that WTP is a work in progress, but the challenges are being successfully resolved as the design and construction move on to completion. (authors)

  17. Can Plant Viruses Cross the Kingdom Border and Be Pathogenic to Humans?

    Directory of Open Access Journals (Sweden)

    Fanny Balique

    2015-04-01

    Full Text Available Phytoviruses are highly prevalent in plants worldwide, including vegetables and fruits. Humans, and more generally animals, are exposed daily to these viruses, among which several are extremely stable. It is currently accepted that a strict separation exists between plant and vertebrate viruses regarding their host range and pathogenicity, and plant viruses are believed to infect only plants. Accordingly, plant viruses are not considered to present potential pathogenicity to humans and other vertebrates. Notwithstanding these beliefs, there are many examples where phytoviruses circulate and propagate in insect vectors. Several issues are raised here that question if plant viruses might further cross the kingdom barrier to cause diseases in humans. Indeed, there is close relatedness between some plant and animal viruses, and almost identical gene repertoires. Moreover, plant viruses can be detected in non-human mammals and humans samples, and there are evidence of immune responses to plant viruses in invertebrates, non-human vertebrates and humans, and of the entry of plant viruses or their genomes into non-human mammal cells and bodies after experimental exposure. Overall, the question raised here is unresolved, and several data prompt the additional extensive study of the interactions between phytoviruses and non-human mammals and humans, and the potential of these viruses to cause diseases in humans.

  18. Occult hepatitis B virus infection is not associated with disease progression of chronic hepatitis C virus infection.

    Science.gov (United States)

    Cho, Junhyeon; Lee, Sang Soo; Choi, Yun Suk; Jeon, Yejoo; Chung, Jung Wha; Baeg, Joo Yeong; Si, Won Keun; Jang, Eun Sun; Kim, Jin-Wook; Jeong, Sook-Hyang

    2016-11-14

    To clarify the prevalence of occult hepatitis B virus (HBV) infection (OBI) and the association between OBI and liver disease progression, defined as development of liver cirrhosis or hepatocellular carcinoma (HCC), worsening of Child-Pugh class, or mortality in cases of chronic hepatitis C virus (HCV) infection. This prospective cohort study enrolled 174 patients with chronic HCV infection (chronic hepatitis, n = 83; cirrhosis, n = 47; HCC, n = 44), and evaluated disease progression during a mean follow-up of 38.7 mo. OBI was defined as HBV DNA positivity in 2 or more different viral genomic regions by nested polymerase chain reaction using 4 sets of primers in the S, C, P and X open reading frame of the HBV genome. The overall OBI prevalence in chronic HCV patients at enrollment was 18.4%, with 16.9%, 25.5% and 13.6% in the chronic hepatitis C, liver cirrhosis and HCC groups, respectively ( P = 0.845). During follow-up, 52 patients showed disease progression, which was independently associated with aspartate aminotransferase > 40 IU/L, Child-Pugh score and sustained virologic response (SVR), but not with OBI positivity. In 136 patients who were not in the SVR state during the study period, OBI positivity was associated with neither disease progression, nor HCC development. The prevalence of OBI in chronic HCV patients was 18.4%, and OBI was not associated with disease progression in South Koreans.

  19. Assessment of airborne virus contamination in wastewater treatment plants.

    Science.gov (United States)

    Masclaux, Frédéric G; Hotz, Philipp; Gashi, Drita; Savova-Bianchi, Dessislava; Oppliger, Anne

    2014-08-01

    Occupational exposure to bioaerosols in wastewater treatment plants (WWTP) and its consequence on workers' health are well documented. Most studies were devoted to enumerating and identifying cultivable bacteria and fungi, as well as measuring concentrations of airborne endotoxins, as these are the main health-related factors found in WWTP. Surprisingly, very few studies have investigated the presence and concentrations of airborne virus in WWTP. However, many enteric viruses are present in wastewater and, due to their small size, they should become aerosolized. Two in particular, the norovirus and the adenovirus, are extremely widespread and are the major causes of infectious gastrointestinal diseases reported around the world. The third one, hepatitis E virus, has an emerging status. This study׳s objectives were to detect and quantify the presence and concentrations of 3 different viruses (adenovirus, norovirus and the hepatitis E virus) in air samples from 31 WWTPs by using quantitative polymerase chain reaction (qPCR) during two different seasons and two consecutive years. Adenovirus was present in 100% of summer WWTP samples and 97% of winter samples. The highest airborne concentration measured was 2.27 × 10(6) genome equivalent/m(3) and, on average, these were higher in summer than in winter. Norovirus was detected in only 3 of the 123 air samples, and the hepatitis E virus was not detected. Concentrations of potentially pathogenic viral particles in WWTP air are non-negligible and could partly explain the work-related gastrointestinal symptoms often reported in employees in this sector. Copyright © 2014 Elsevier Inc. All rights reserved.

  20. Distribution of Tomato spotted wilt virus in dahlia plants.

    Science.gov (United States)

    Asano, S; Hirayama, Y; Matsushita, Y

    2017-04-01

    Tomato spotted wilt virus (TSWV) causes significant losses in the production of the ornamental plant Dahlia variabilis in Japan. The purpose of this study was to examine the distribution of TSWV in dahlia plants and identify plant parts that can be used in the selection of TSWV-free plants. The distribution of TSWV was investigated using reverse transcriptional polymerase chain reaction (RT-PCR) and tissue blot immunoassay. The detection rate of TSWV in latent infected compound leaves was the highest in the petiole, and it decreased from the veins and rachis to the lamina. The tissue blot immunoassays of the leaflets showed an uneven distribution of TSWV, especially along the edge of the leaf blade. In stems, the detection rate of TSWV was high partway up the stem compared to that in the upper and the lower parts of the stem during the vegetative growth stage. A highly uneven distribution was observed in the bulb. Our results indicated that middle parts of the stem as well as the petioles, rachis, and veins of compound leaves are suitable for detection of TSWV in dahlias. This study is the first to report uneven distribution of TSWV in dahlia plants. In this study, the distribution of Tomato spotted wilt virus (TSWV) in various parts of dahlia plants was investigated for the first time. The distribution of TSWV was uneven in compound leaves, leaflets, stems, and bulbs. The middle parts of the stem or the petiole and leaf veins should be sampled to detect TSWV when selecting healthy plants. © 2017 The Society for Applied Microbiology.

  1. Progress report on the investigation of nuclear plant costs

    International Nuclear Information System (INIS)

    Kent, G.F.

    1987-01-01

    Over the past few years, many studies have been performed in an effort to understand, evaluate, and explain the reasons for the substantial increases in nuclear plant costs, as well as for the divergence between predicted and actual costs. Concerns regarding these cost increases is shared by utility owners, engineer/constructors, and public utility commissions. The future use of nuclear power depends on the ability of the industry to control these costs while maintaining safety. Stone and Webster Engineering Corporation (SWEC) has responded to this concern by initiating an internal study to evaluate, quantify, and explain the factors influencing this cost growth. Previously, a conceptual approach was presented in which three explanatory variables or factors were used as surrogates for the many variables that affected plant cost. This paper presents a progress report of that continuing study

  2. Folates in plants: research advances and progress in crop biofortification

    Science.gov (United States)

    Gorelova, Vera; Ambach, Lars; Rébeillé, Fabrice; Stove, Christophe; Van Der Straeten, Dominique

    2017-03-01

    Folates, also known as B9 vitamins, serve as donors and acceptors in one-carbon (C1) transfer reactions. The latter are involved in synthesis of many important biomolecules, such as amino acids, nucleic acids and vitamin B5. Folates also play a central role in the methyl cycle that provides one-carbon groups for methylation reactions. The important functions fulfilled by folates make them essential in all living organisms. Plants, being able to synthesize folates de novo, serve as an excellent dietary source of folates for animals that lack the respective biosynthetic pathway. Unfortunately, the most important staple crops such as rice, potato and maize are rather poor sources of folates. Insufficient folate consumption is known to cause severe developmental disorders in humans. Two approaches are employed to fight folate deficiency: pharmacological supplementation in the form of folate pills and biofortification of staple crops. As the former approach is considered rather costly for the major part of the world population, biofortification of staple crops is viewed as a decent alternative in the struggle against folate deficiency. Therefore strategies, challenges and recent progress of folate enhancement in plants will be addressed in this review. Apart from the ever-growing need for the enhancement of nutritional quality of crops, the world population faces climate change catastrophes or environmental stresses, such as elevated temperatures, drought, salinity that severely affect growth and productivity of crops. Due to immense diversity of their biochemical functions, folates take part in virtually every aspect of plant physiology. Any disturbance to the plant folate metabolism leads to severe growth inhibition and, as a consequence, to a lower productivity. Whereas today’s knowledge of folate biochemistry can be considered very profound, evidence on the physiological roles of folates in plants only starts to emerge. In the current review we will discuss the

  3. Progress toward an enhanced vaccine: Eight marked attenuated viruses to porcine reproductive and respiratory disease virus.

    Science.gov (United States)

    Spear, Allyn; Wang, Feng-Xue; Kappes, Matthew A; Das, Phani B; Faaberg, Kay S

    2018-03-01

    Recombinant viruses of strain Ingelvac® PRRS porcine reproductive and respiratory syndrome virus (PRRSV) modified live virus vaccine were produced with two individual small in-frame deletions in nonstructural protein 2 (nsp2; Δ23 and Δ87) and also the same deletions supplanted with foreign tags (Δ23-V5, Δ23-FLAG, Δ23-S, Δ87-V5, Δ87-FLAG, Δ87-S). The viruses, but one (Δ87-FLAG), were stable for 10 passages and showed minimal effects on in vitro growth. Northern hybridization showed that the Δ23-tagged probe detected intracellular viral genome RNA as well as shorter RNAs that may represent heteroclite species, while the Δ87-tagged probe detected predominantly only genome length RNAs. When the tagged viruses were used to probe nsp2 protein in infected cells, perinuclear localization similar to native nsp2 was seen. Dual infection of Δ23-S and Δ87-S viruses allowed some discrimination of individual tagged nsp2 protein, facilitating future research. The mutants could potentially also be used to differentiate infected from vaccinated animals. Published by Elsevier Inc.

  4. Rapidly progressive periodontal disease associated with human immunodeficiency virus

    International Nuclear Information System (INIS)

    Hezaim, K.A.; Javed, F.; Askar, A.; Rasheed, A.A.

    2012-01-01

    Severe periodontal inflammation with generalized dental plaque accumulation, spontaneous and severe gingival bleeding, fungal infection, and inter dental papillae necrosis are presented in a patient infected with human immunodeficiency virus (HIV). Bite-wing radiographs revealed a generalized horizontal alveolar bone loss of 7-8 millimetres in both arches. Erythematous patches were noted on the gingival mucosa in both jaws. DNA testing was performed to identify the periodontopathogens. The patient had no signs or symptoms of acquired immunodeficiency syndrome. This case-report presents the massive periodontal destruction that occurred in a patient infected with HIV. Therefore, it is highly recommended that patients infected with HIV should be regularly monitored to aid in early detection and to provide proper management of periodontal inflammatory conditions to minimize its destruction. (author)

  5. Bat guano virome: predominance of dietary viruses from insects and plants plus novel mammalian viruses

    Science.gov (United States)

    Li, Linlin; Joseph, G. Victoria; Wang, Chunlin; Jones, Morris; Fellers, Gary M.; Kunz, Thomas H.; Delwart, Eric

    2010-01-01

    Bats are hosts to a variety of viruses capable of zoonotic transmissions. Because of increased contact between bats, humans, and other animal species, the possibility exists for further cross-species transmissions and ensuing disease outbreaks. We describe here full and partial viral genomes identified using metagenomics in the guano of bats from California and Texas. A total of 34% and 58% of 390,000 sequence reads from bat guano in California and Texas, respectively, were related to eukaryotic viruses, and the largest proportion of those infect insects, reflecting the diet of these insectivorous bats, including members of the viral families Dicistroviridae, Iflaviridae, Tetraviridae, and Nodaviridae and the subfamily Densovirinae. The second largest proportion of virus-related sequences infects plants and fungi, likely reflecting the diet of ingested insects, including members of the viral families Luteoviridae, Secoviridae, Tymoviridae, and Partitiviridae and the genus Sobemovirus. Bat guano viruses related to those infecting mammals comprised the third largest group, including members of the viral families Parvoviridae, Circoviridae, Picornaviridae, Adenoviridae, Poxviridae, Astroviridae, and Coronaviridae. No close relative of known human viral pathogens was identified in these bat populations. Phylogenetic analysis was used to clarify the relationship to known viral taxa of novel sequences detected in bat guano samples, showing that some guano viral sequences fall outside existing taxonomic groups. This initial characterization of the bat guano virome, the first metagenomic analysis of viruses in wild mammals using second-generation sequencing, therefore showed the presence of previously unidentified viral species, genera, and possibly families. Viral metagenomics is a useful tool for genetically characterizing viruses present in animals with the known capability of direct or indirect viral zoonosis to humans.

  6. Nuclear challenges and progress in designing stellarator fusion power plants

    International Nuclear Information System (INIS)

    El-Guebaly, L.A.; Wilson, P.; Henderson, D.; Sawan, M.; Sviatoslavsky, G.; Tautges, T.; Slaybaugh, R.; Kiedrowski, B.; Ibrahim, A.

    2008-01-01

    Over the past 5-6 decades, stellarator power plants have been studied in the US, Europe, and Japan as an alternate to the mainline magnetic fusion tokamaks, offering steady-state operation and eliminating the risk of plasma disruptions. The earlier 1980s studies suggested large-scale stellarator power plants with an average major radius exceeding 20 m. The most recent development of the compact stellarator concept delivered ARIES-CS - a compact stellarator with 7.75 m average major radius, approaching that of tokamaks. For stellarators, the most important engineering parameter that determines the machine size and cost is the minimum distance between the plasma boundary and mid-coil. Accommodating the breeding blanket and necessary shield within this distance to protect the ARIES-CS superconducting magnet represents a challenging task. Selecting the ARIES-CS nuclear and engineering parameters to produce an economic optimum, modeling the complex geometry for 3D nuclear analysis to confirm the key parameters, and minimizing the radwaste stream received considerable attention during the design process. These engineering design elements combined with advanced physics helped enable the compact stellarator to be a viable concept. This paper provides a brief historical overview of the progress in designing stellarator power plants and a perspective on the successful integration of the nuclear activity into the final ARIES-CS configuration

  7. Analysis of ovine colostrum to detect antibody against progressive pneumonia virus.

    OpenAIRE

    Taylor, T B; Banowetz, G M; Schipper, I A; Gabrielson, D A

    1982-01-01

    Immunoglobulins were isolated and purified from the colostrum and serum of progressive pneumonia virus infected sheep and also from non-infected control sheep. Four classes of immunoglobulins were isolated from sheep colostrum (IgG1, IgG2, IgA and Ig10s). Three classes of immunoglobulins were isolated from sheep serum (IgG1, IgG2 and IgM). Low levels of virus neutralizing activity were demonstrated only in the whole serum and purified serum IgG1 preparations. No complement fixing activity was...

  8. The mathematics of virus shell assembly. Progress report 1995--1996

    Energy Technology Data Exchange (ETDEWEB)

    Berger, B.

    1996-08-01

    This research focuses on applying computational and mathematical techniques to problems in biology, and more specifically to problems in protein folding. Significant progress has been made in the following areas relating to virus shell assembly: the local rules theory has been further developed; development has begun on a second-generation simulator which provides a more physically realistic model of assembly, collaborative efforts have continued with an experimental biologist to verify and inspire the local rules theory; an investigation has been initiated into the mechanics of virus shell assembly; laboratory experiments have been conducted on bacteriophage T4 which verify that the previously believed structure for the core may be incorrect.

  9. Progress in the Identification of Dengue Virus Entry/Fusion Inhibitors

    Directory of Open Access Journals (Sweden)

    Carolina De La Guardia

    2014-01-01

    Full Text Available Dengue fever, a reemerging disease, is putting nearly 2.5 billion people at risk worldwide. The number of infections and the geographic extension of dengue fever infection have increased in the past decade. The disease is caused by the dengue virus, a flavivirus that uses mosquitos Aedes sp. as vectors. The disease has several clinical manifestations, from the mild cold-like illness to the more serious hemorrhagic dengue fever and dengue shock syndrome. Currently, there is no approved drug for the treatment of dengue disease or an effective vaccine to fight the virus. Therefore, the search for antivirals against dengue virus is an active field of research. As new possible receptors and biological pathways of the virus biology are discovered, new strategies are being undertaken to identify possible antiviral molecules. Several groups of researchers have targeted the initial step in the infection as a potential approach to interfere with the virus. The viral entry process is mediated by viral proteins and cellular receptor molecules that end up in the endocytosis of the virion, the fusion of both membranes, and the release of viral RNA in the cytoplasm. This review provides an overview of the targets and progress that has been made in the quest for dengue virus entry inhibitors.

  10. Plant viruses as scaffolds for the presentation of vaccine epitopes

    Czech Academy of Sciences Publication Activity Database

    Plchová, Helena; Čeřovská, Noemi; Vaculík, Petr; Moravec, Tomáš

    2017-01-01

    Roč. 61, č. 1 (2017), s. 1-12 ISSN 0006-3134 R&D Projects: GA ČR(CZ) GA15-10768S; GA ČR(CZ) GAP501/12/1761 Grant - others:European Regional Development Fund(XE) CZ.2.16/3.1.00/24014 Institutional support: RVO:61389030 Keywords : tobacco-mosaic-virus * x coat protein * human-papillomavirus type-16 * green fluorescent protein * n-terminal segment * triple gene block * cell-to-cell * transient expression * nicotiana-benthamiana * viral vector * transient expression * plant viral expression vectors Subject RIV: GE - Plant Breeding OBOR OECD: Virology Impact factor: 1.551, year: 2016

  11. Early depletion of proliferating B cells of germinal center in rapidly progressive simian immunodeficiency virus infection

    International Nuclear Information System (INIS)

    Zhang Zhiqiang; Casimiro, Danilo R.; Schleif, William A.; Chen, Minchun; Citron, Michael; Davies, Mary-Ellen; Burns, Janine; Liang, Xiaoping; Fu, Tong-Ming; Handt, Larry; Emini, Emilio A.; Shiver, John W.

    2007-01-01

    Lack of virus specific antibody response is commonly observed in both HIV-1-infected humans and SIV-infected monkeys with rapid disease progression. However, the mechanisms underlying this important observation still remain unclear. In a titration study of a SIVmac239 viral stock, three out of six animals with viral inoculation rapidly progressed to AIDS within 5 months. Unexpectedly, there was no obvious depletion of CD4 + T cells in both peripheral and lymph node (LN) compartments in these animals. Instead, progressive depletion of proliferating B cells and disruption of the follicular dendritic cell (FDC) network in germinal centers (GC) was evident in the samples collected at as early as 20 days after viral challenge. This coincided with undetectable, or weak and transient, virus-specific antibody responses over the course of infection. In situ hybridization of SIV RNA in the LN samples revealed a high frequency of SIV productively infected cells and large amounts of accumulated viral RNA in the GCs in these animals. Early severe depletion of GC proliferating B cells and disruption of the FDC network may thus result in an inability to mount a virus-specific antibody response in rapid progressors, which has been shown to contribute to accelerated disease progression of SIV infection

  12. Chimeric plant virus particles administered nasally or orally induce systemic and mucosal immune responses in mice

    DEFF Research Database (Denmark)

    Brennan, F.R.; Bellaby, T.; Helliwell, S.M.

    1999-01-01

    The humoral immune responses to the D2 peptide of fibronectin-binding protein B (FnBP) of Staphylococcus aureus, expressed on the plant virus cowpea mosaic virus (CPMV), were evaluated after mucosal delivery to mice. Intranasal immunization of these chimeric virus particles (CVPs), either alone...

  13. Virus infection mediates the effects of elevated CO2 on plants and vectors

    Science.gov (United States)

    Trębicki, Piotr; Vandegeer, Rebecca K.; Bosque-Pérez, Nilsa A.; Powell, Kevin S.; Dader, Beatriz; Freeman, Angela J.; Yen, Alan L.; Fitzgerald, Glenn J.; Luck, Jo E.

    2016-03-01

    Atmospheric carbon dioxide (CO2) concentration has increased significantly and is projected to double by 2100. To increase current food production levels, understanding how pests and diseases respond to future climate driven by increasing CO2 is imperative. We investigated the effects of elevated CO2 (eCO2) on the interactions among wheat (cv. Yitpi), Barley yellow dwarf virus and an important pest and virus vector, the bird cherry-oat aphid (Rhopalosiphum padi), by examining aphid life history, feeding behavior and plant physiology and biochemistry. Our results showed for the first time that virus infection can mediate effects of eCO2 on plants and pathogen vectors. Changes in plant N concentration influenced aphid life history and behavior, and N concentration was affected by virus infection under eCO2. We observed a reduction in aphid population size and increased feeding damage on noninfected plants under eCO2 but no changes to population and feeding on virus-infected plants irrespective of CO2 treatment. We expect potentially lower future aphid populations on noninfected plants but no change or increased aphid populations on virus-infected plants therefore subsequent virus spread. Our findings underscore the complexity of interactions between plants, insects and viruses under future climate with implications for plant disease epidemiology and crop production.

  14. Virus infection mediates the effects of elevated CO2 on plants and vectors

    Science.gov (United States)

    Trębicki, Piotr; Vandegeer, Rebecca K.; Bosque-Pérez, Nilsa A.; Powell, Kevin S.; Dader, Beatriz; Freeman, Angela J.; Yen, Alan L.; Fitzgerald, Glenn J.; Luck, Jo E.

    2016-01-01

    Atmospheric carbon dioxide (CO2) concentration has increased significantly and is projected to double by 2100. To increase current food production levels, understanding how pests and diseases respond to future climate driven by increasing CO2 is imperative. We investigated the effects of elevated CO2 (eCO2) on the interactions among wheat (cv. Yitpi), Barley yellow dwarf virus and an important pest and virus vector, the bird cherry-oat aphid (Rhopalosiphum padi), by examining aphid life history, feeding behavior and plant physiology and biochemistry. Our results showed for the first time that virus infection can mediate effects of eCO2 on plants and pathogen vectors. Changes in plant N concentration influenced aphid life history and behavior, and N concentration was affected by virus infection under eCO2. We observed a reduction in aphid population size and increased feeding damage on noninfected plants under eCO2 but no changes to population and feeding on virus-infected plants irrespective of CO2 treatment. We expect potentially lower future aphid populations on noninfected plants but no change or increased aphid populations on virus-infected plants therefore subsequent virus spread. Our findings underscore the complexity of interactions between plants, insects and viruses under future climate with implications for plant disease epidemiology and crop production. PMID:26941044

  15. PROGRESSION OF LIVER FIBROSIS IN MONOINFECTED PATIENTS BY HEPATITIS C VIRUS AND COINFECTED BY HCV AND HUMAN IMMUNODEFICIENCY VIRUS

    Directory of Open Access Journals (Sweden)

    Cristiane Valle TOVO

    2013-03-01

    Full Text Available Context The progression of liver fibrosis in patients coinfected by hepatitis C virus and human immunodeficiency virus (HCV/HIV has been increasingly studied in the past decade. Studies made before the highly active antiretroviral therapy suggest that HIV can change the natural history of the HCV infection, leading to a faster progression of the liver fibrosis. Objective To evaluate and compare the fibrosis progression in two groups of patients (HCV/HIV coinfected and HCV monoinfected Methods Seventy patients HCV monoinfected and 26 patients HCV/HIV coinfected who had not undertaken HCV treatment and were submitted to serial percutaneous liver biopsies were retrospectively evaluated. There was no difference in the fibrosis progression between the two groups. Conclusion The fibrosis grade evolution was not worse in the coinfected patients. The immunosuppression absence and the shortest time period between the biopsies in the coinfected group are possible explanations. Contexto A progressão da fibrose hepática em pacientes coinfectados pelos vírus da hepatite C (VHC e da imunodeficiência humana (VHC/HIV tem sido mais estudada na última década. Estudos realizados antes da terapia antiretroviral de alta potência (HAART sugerem que o HIV pode mudar a história natural da infecção pelo VHC, levando a uma progressão mais rápida da fibrose hepática. Objetivo Avaliar e comparar a progressão de fibrose em duas populações de pacientes (coinfectados VHC/HIV e monoinfectados VHC. Métodos Foram avaliados retrospectivamente 70 pacientes monoinfectados VHC e 26 coinfectados VHC/HIV nunca tratados para o VHC e que haviam realizado duas biopsias hepáticas seriadas. Não houve diferença na progressão de fibrose entre os dois grupos. Conclusão A evolução do grau de fibrose não foi pior nos pacientes coinfectados. A ausência de imunodepressão e o menor intervalo de tempo entre as biopsias no grupo de coinfectados são poss

  16. Method of inhibiting plant virus pathogen infections by crispr/cas9-mediated interference

    KAUST Repository

    Mahfouz, Magdy Mahmoud

    2016-11-24

    A genetically modified tobacco plant or tomato plant resistant to at least one pathogenic geminiviridae virus species is provided. The plant comprises a heterologous CRISPR/Cas9 system and at least one heterologous nucleotide sequence that is capable of hybridizing to a nucleotide sequence of the pathogenic virus and that directs inactivation of the pathogenic virus species or plurality of viral species by the CRISPR/Cas9 system. The heterologous nucleotide sequence can be complementary to, but not limited to an Intergenic Region (IR) of the Tomato Yellow Leaf Curl Virus (TYLCV), Further provided are methods of generating a genetically modified plant that is resistant to a virus pathogen by a heterologous CRISPR/Cas9 system and expression of a gRNA specifically targeting the virus.

  17. Human T cell leukemia virus reactivation with progression of adult T-cell leukemia-lymphoma.

    Directory of Open Access Journals (Sweden)

    Lee Ratner

    Full Text Available Human T-cell leukemia virus-associated adult T-cell leukemia-lymphoma (ATLL has a very poor prognosis, despite trials of a variety of different treatment regimens. Virus expression has been reported to be limited or absent when ATLL is diagnosed, and this has suggested that secondary genetic or epigenetic changes are important in disease pathogenesis.We prospectively investigated combination chemotherapy followed by antiretroviral therapy for this disorder. Nineteen patients were prospectively enrolled between 2002 and 2006 at five medical centers in a phase II clinical trial of infusional chemotherapy with etoposide, doxorubicin, and vincristine, daily prednisone, and bolus cyclophosphamide (EPOCH given for two to six cycles until maximal clinical response, and followed by antiviral therapy with daily zidovudine, lamivudine, and alpha interferon-2a for up to one year. Seven patients were on study for less than one month due to progressive disease or chemotherapy toxicity. Eleven patients achieved an objective response with median duration of response of thirteen months, and two complete remissions. During chemotherapy induction, viral RNA expression increased (median 190-fold, and virus replication occurred, coincident with development of disease progression.EPOCH chemotherapy followed by antiretroviral therapy is an active therapeutic regimen for adult T-cell leukemia-lymphoma, but viral reactivation during induction chemotherapy may contribute to treatment failure. Alternative therapies are sorely needed in this disease that simultaneously prevent virus expression, and are cytocidal for malignant cells.

  18. A Cerebellar Tremor in a Patient with Human Immunodeficiency Virus-1 Associated with Progressive Multifocal Leukoencephalopathy

    Directory of Open Access Journals (Sweden)

    Hee-Jin Kim

    2009-10-01

    Full Text Available Progressive multifocal leukoencephalopathy (PML is a demyelinating disease of the central nervous system (CNS caused by JC virus infection in oligodendrocytes, especially in patients with acquired immunodeficiency syndrome (AIDS. Movement disorders associated with PML are very rare. Here, we report a case of PML in an AIDS patient who presented with a cerebellar tremor, caused by lesions in the cerebellar outflow tract. A cerebellar tremor can be a rare clinical manifestation in patients with PML.

  19. A Cerebellar Tremor in a Patient with Human Immunodeficiency Virus-1 Associated with Progressive Multifocal Leukoencephalopathy

    Science.gov (United States)

    Kim, Hee-Jin; Lee, Jae-Jung; Lee, Phil Hyu

    2009-01-01

    Progressive multifocal leukoencephalopathy (PML) is a demyelinating disease of the central nervous system (CNS) caused by JC virus infection in oligodendrocytes, especially in patients with acquired immunodeficiency syndrome (AIDS). Movement disorders associated with PML are very rare. Here, we report a case of PML in an AIDS patient who presented with a cerebellar tremor, caused by lesions in the cerebellar outflow tract. A cerebellar tremor can be a rare clinical manifestation in patients with PML. PMID:24868366

  20. Savannah River Plant Works Technical Department monthly progress report for May 1958: Deleted Version

    Energy Technology Data Exchange (ETDEWEB)

    1958-06-17

    This progress report by the Atomic Energy Division of the Savannah River Plant covers: Reactor Technology; Separation Technology; Engineering Assistance; Health Physics; and General Laboratory Work. (JT)

  1. Plant Immunity against Viruses: Moving from the Lab to the Field

    Directory of Open Access Journals (Sweden)

    Nam-Yeon Kim

    2018-03-01

    Full Text Available Plant viruses cause significant yield losses and continuously threaten crop production, representing a serious threat to global food security. Studies on plant-virus interactions have contributed to increase our knowledge on plant immunity mechanism, providing new strategies for crop improvement. The prophylactic managements consist mainly following international legislations, eradication of infected plants, and application of pesticide to decrease the population of vectors. Hence, putting together the pieces of knowledge related to molecular plant immunity to viruses is critical for the control of virus disease in fields. Over the last several decades, the outstanding outcomes of extensive research have been achieved on comprehension of plant immunity to viruses. Although most dominant R genes have been used as natural resistance genes, recessive resistance genes have been deployed in several crops as another efficient strategy to control viruses. In addition, RNA interference also regulates plant immunity and contribute a very efficient antiviral system at the nucleic acid level. This review aims at describing virus disease on crops and summarizes current resistance mechanisms. Furthermore, we will discuss the current biotechnological approaches to control viral diseases and the future questions that are to be addressed to secure crop production against viruses.

  2. Replication of an incomplete alfalfa mosaic virus genome in plants transformed with viral replicase genes

    NARCIS (Netherlands)

    Taschner, P. E.; van der Kuyl, A. C.; Neeleman, L.; Bol, J. F.

    1991-01-01

    RNAs 1 and 2 of alfalfa mosaic virus (AIMV) encode proteins P1 and P2, respectively, both of which have a putative role in viral RNA replication. Tobacco plants were transformed with DNA copies of RNA1 (P1-plants), RNA2 (P2-plants) or a combination of these two cDNAs (P12-plants). All transgenic

  3. Virus infection decreases the attractiveness of white clover plants for a non-vectoring herbivore

    DEFF Research Database (Denmark)

    van Mölken, Tamara; Caluwe, Hannie de; Hordijk, Cornelis A.

    2012-01-01

    Plant pathogens and insect herbivores are prone to share hosts under natural conditions. Consequently, pathogen-induced changes in the host plant can affect herbivory, and vice versa. Even though plant viruses are ubiquitous in the field, little is known about plant-mediated interactions between ...

  4. Differential profiles of direct and indirect modification of vector feeding behaviour by a plant virus.

    Science.gov (United States)

    He, Wen-Bo; Li, Jie; Liu, Shu-Sheng

    2015-01-08

    Plant viruses interact with their insect vectors directly and indirectly via host plants, and this tripartite interaction may produce fitness benefits to both the vectors and the viruses. Our previous studies show that the Middle East-Asia Minor 1 (MEAM1) species of the whitefly Bemisia tabaci complex improved its performance on tobacco plants infected by the Tomato yellow leaf curl China virus (TYLCCNV), which it transmits, although virus infection of the whitefly per se reduced its performance. Here, we use electrical penetration graph recording to investigate the direct and indirect effects of TYLCCNV on the feeding behaviour of MEAM1. When feeding on either cotton, a non-host of TYLCCNV, or uninfected tobacco, a host of TYLCCNV, virus-infection of the whiteflies impeded their feeding. Interestingly, when viruliferous whiteflies fed on virus-infected tobacco, their feeding activities were no longer negatively affected; instead, the virus promoted whitefly behaviour related to rapid and effective sap ingestion. Our findings show differential profiles of direct and indirect modification of vector feeding behaviour by a plant virus, and help to unravel the behavioural mechanisms underlying a mutualistic relationship between an insect vector and a plant virus that also has features reminiscent of an insect pathogen.

  5. Clinical reactivations of herpes simplex virus type 2 infection and human immunodeficiency virus disease progression markers.

    Directory of Open Access Journals (Sweden)

    Bulbulgul Aumakhan

    Full Text Available BACKGROUND: The natural history of HSV-2 infection and role of HSV-2 reactivations in HIV disease progression are unclear. METHODS: Clinical symptoms of active HSV-2 infection were used to classify 1,938 HIV/HSV-2 co-infected participants of the Women's Interagency HIV Study (WIHS into groups of varying degree of HSV-2 clinical activity. Differences in plasma HIV RNA and CD4+ T cell counts between groups were explored longitudinally across three study visits and cross-sectionally at the last study visit. RESULTS: A dose dependent association between markers of HIV disease progression and degree of HSV-2 clinical activity was observed. In multivariate analyses after adjusting for baseline CD4+ T cell levels, active HSV-2 infection with frequent symptomatic reactivations was associated with 21% to 32% increase in the probability of detectable plasma HIV RNA (trend p = 0.004, an average of 0.27 to 0.29 log10 copies/ml higher plasma HIV RNA on a continuous scale (trend p<0.001 and 51 to 101 reduced CD4+ T cells/mm(3 over time compared to asymptomatic HSV-2 infection (trend p<0.001. CONCLUSIONS: HIV induced CD4+ T cell loss was associated with frequent symptomatic HSV-2 reactivations. However, effect of HSV-2 reactivations on HIV disease progression markers in this population was modest and appears to be dependent on the frequency and severity of reactivations. Further studies will be necessary to determine whether HSV-2 reactivations contribute to acceleration of HIV disease progression.

  6. Nuclear challenges and progress in designing stellarator power plants

    International Nuclear Information System (INIS)

    El-Guebaly, L.

    2007-01-01

    , such as recycling (within the nuclear industry) and clearance (or unconditional release to the commercial market). The ARIES-CS bioshield, cryostat, and individual magnet constituents qualify for clearance, representing ∼80% of the total waste volume. We developed a recycling approach for the non-clearable, in-vessel components using a combination of conventional and advanced remote handling equipment that can handle high doses of 3000 Sv/h or more. Several additional nuclear-related tasks received considerable attention during the ARIES-CS design process. These include the radial build definition, the well-optimized in-vessel components that satisfy the top-level requirements, the carefully selected nuclear and engineering parameters to produce an economic optimum, and the overarching safety constraints to deliver a safe and reliable power plant. This paper provides a brief historical overview of the progress in designing stellarator power plants and a perspective to the successful integration of the nuclear activity into the final ARIES-CS design

  7. [Research progress of genetic engineering on medicinal plants].

    Science.gov (United States)

    Teng, Zhong-qiu; Shen, Ye

    2015-02-01

    The application of genetic engineering technology in modern agriculture shows its outstanding role in dealing with food shortage. Traditional medicinal plant cultivation and collection have also faced with challenges, such as lack of resources, deterioration of environment, germplasm of recession and a series of problems. Genetic engineering can be used to improve the disease resistance, insect resistance, herbicides resistant ability of medicinal plant, also can improve the medicinal plant yield and increase the content of active substances in medicinal plants. Thus, the potent biotechnology can play an important role in protection and large area planting of medicinal plants. In the development of medicinal plant genetic engineering, the safety of transgenic medicinal plants should also be paid attention to. A set of scientific safety evaluation and judgment standard which is suitable for transgenic medicinal plants should be established based on the recognition of the particularity of medicinal plants.

  8. Novel RNA viruses within plant parasitic cyst nematodes.

    Science.gov (United States)

    Ruark, Casey L; Gardner, Michael; Mitchum, Melissa G; Davis, Eric L; Sit, Tim L

    2018-01-01

    The study of invertebrate-and particularly nematode-viruses is emerging with the advancement of transcriptome sequencing. Five single-stranded RNA viruses have now been confirmed within the economically important soybean cyst nematode (SCN; Heterodera glycines). From previous research, we know these viruses to be widespread in greenhouse and field populations of SCN. Several of the SCN viruses were also confirmed within clover (H. trifolii) and beet (H. schachtii) cyst nematodes. In the presented study, we sequenced the transcriptomes of several inbred SCN populations and identified two previously undiscovered viral-like genomes. Both of these proposed viruses are negative-sense RNA viruses and have been named SCN nyami-like virus (NLV) and SCN bunya-like virus (BLV). Finally, we analyzed publicly available transcriptome data of two potato cyst nematode (PCN) species, Globodera pallida and G. rostochiensis. From these data, a third potential virus was discovered and called PCN picorna-like virus (PLV). PCN PLV is a positive-sense RNA virus, and to the best of our knowledge, is the first virus described within PCN. The presence of these novel viruses was confirmed via qRT-PCR, endpoint PCR, and Sanger sequencing with the exception of PCN PLV due to quarantine restrictions on the nematode host. While much work needs to be done to understand the biological and evolutionary significance of these viruses, they offer insight into nematode ecology and the possibility of novel nematode management strategies.

  9. Effects of introduced and indigenous viruses on native plants: exploring their disease causing potential at the agro-ecological interface.

    Science.gov (United States)

    Vincent, Stuart J; Coutts, Brenda A; Jones, Roger A C

    2014-01-01

    The ever increasing movement of viruses around the world poses a major threat to plants growing in cultivated and natural ecosystems. Both generalist and specialist viruses move via trade in plants and plant products. Their potential to damage cultivated plants is well understood, but little attention has been given to the threat such viruses pose to plant biodiversity. To address this, we studied their impact, and that of indigenous viruses, on native plants from a global biodiversity hot spot in an isolated region where agriculture is very recent (viruses readily. To establish their potential to cause severe or mild systemic symptoms in different native plant species, we used introduced generalist and specialist viruses, and indigenous viruses, to inoculate plants of 15 native species belonging to eight families. We also measured resulting losses in biomass and reproductive ability for some host-virus combinations. In addition, we sampled native plants growing over a wide area to increase knowledge of natural infection with introduced viruses. The results suggest that generalist introduced viruses and indigenous viruses from other hosts pose a greater potential threat than introduced specialist viruses to populations of native plants encountered for the first time. Some introduced generalist viruses infected plants in more families than others and so pose a greater potential threat to biodiversity. The indigenous viruses tested were often surprisingly virulent when they infected native plant species they were not adapted to. These results are relevant to managing virus disease in new encounter scenarios at the agro-ecological interface between managed and natural vegetation, and within other disturbed natural vegetation situations. They are also relevant for establishing conservation policies for endangered plant species and avoiding spread of damaging viruses to undisturbed natural vegetation beyond the agro-ecological interface.

  10. Emphysema Distribution and Diffusion Capacity Predict Emphysema Progression in Human Immunodeficiency Virus Infection

    Science.gov (United States)

    Leung, Janice M; Malagoli, Andrea; Santoro, Antonella; Besutti, Giulia; Ligabue, Guido; Scaglioni, Riccardo; Dai, Darlene; Hague, Cameron; Leipsic, Jonathon; Sin, Don D.; Man, SF Paul; Guaraldi, Giovanni

    2016-01-01

    Background Chronic obstructive pulmonary disease (COPD) and emphysema are common amongst patients with human immunodeficiency virus (HIV). We sought to determine the clinical factors that are associated with emphysema progression in HIV. Methods 345 HIV-infected patients enrolled in an outpatient HIV metabolic clinic with ≥2 chest computed tomography scans made up the study cohort. Images were qualitatively scored for emphysema based on percentage involvement of the lung. Emphysema progression was defined as any increase in emphysema score over the study period. Univariate analyses of clinical, respiratory, and laboratory data, as well as multivariable logistic regression models, were performed to determine clinical features significantly associated with emphysema progression. Results 17.4% of the cohort were emphysema progressors. Emphysema progression was most strongly associated with having a low baseline diffusion capacity of carbon monoxide (DLCO) and having combination centrilobular and paraseptal emphysema distribution. In adjusted models, the odds ratio (OR) for emphysema progression for every 10% increase in DLCO percent predicted was 0.58 (95% confidence interval [CI] 0.41–0.81). The equivalent OR (95% CI) for centrilobular and paraseptal emphysema distribution was 10.60 (2.93–48.98). Together, these variables had an area under the curve (AUC) statistic of 0.85 for predicting emphysema progression. This was an improvement over the performance of spirometry (forced expiratory volume in 1 second to forced vital capacity ratio), which predicted emphysema progression with an AUC of only 0.65. Conclusion Combined paraseptal and centrilobular emphysema distribution and low DLCO could identify HIV patients who may experience emphysema progression. PMID:27902753

  11. A mini-review of anti-hepatitis B virus activity of medicinal plants

    Directory of Open Access Journals (Sweden)

    Manzer H. Siddiqui

    2017-01-01

    Full Text Available Medicinal plants are of undoubted value, as they have been used for centuries to treat various diseases and health disorders in almost every part of the world. In several studies, the use of medicinal plants was found effective in treatment of infectious and non-infectious diseases. The World Health Organization has been working for many years to identify all surviving medicinal plants on the earth. An important step has also been taken by the Natural Health Product Regulation of Canada for promotion and usages of natural products. At present, the rapidly growing population of the world is facing many challenges from various infectious diseases that are associated with hepatitis A, B and C virus, human immunodeficiency virus, influenza virus, dengue virus and new emerging viruses. Hepatitis B virus causes a severe and frequently transmittable disease of the liver. Millions of people worldwide suffer from hepatitis B virus (HBV infection. The drugs available on the market for the treatment of hepatitis B are not sufficient and also cause side effects in patients suffering from HBV infection. The pharmaceutical companies are searching for suitable alternative and natural inhibitors of HBV. Therefore, it is important to explore and use plants as a source of new medicines to treat this infectious disease, because single plants contain a priceless pool of active ingredients which could help in the production of pharmaceutical-grade peptides or proteins. However, the knowledge of the antiviral activity of medicinal plants is still limited.

  12. Interplays between soil-borne plant viruses and RNA silencing-mediated antiviral defense in roots

    Directory of Open Access Journals (Sweden)

    Ida Bagus Andika

    2016-09-01

    Full Text Available Although the majority of plant viruses are transmitted by arthropod vectors and invade the host plants through the aerial parts, there is a considerable number of plant viruses that infect roots via soil-inhabiting vectors such as plasmodiophorids, chytrids, and nematodes. These soil-borne viruses belong to diverse families, and many of them cause serious diseases in major crop plants. Thus, roots are important organs for the life cycle of many viruses. Compared to shoots, roots have a distinct metabolism and particular physiological characteristics due to the differences in development, cell composition, gene expression patterns, and surrounding environmental conditions. RNA silencing is an important innate defense mechanism to combat virus infection in plants, but the specific information on the activities and molecular mechanism of RNA silencing-mediated viral defense in root tissue is still limited. In this review, we summarize and discuss the current knowledge regarding RNA silencing aspects of the interactions between soil-borne viruses and host plants. Overall, research evidence suggests that soil-borne viruses have evolved to adapt to the distinct mechanism of antiviral RNA silencing in roots.

  13. Effects of Introduced and Indigenous Viruses on Native Plants: Exploring Their Disease Causing Potential at the Agro-Ecological Interface

    Science.gov (United States)

    Vincent, Stuart J.; Coutts, Brenda A.; Jones, Roger A. C.

    2014-01-01

    The ever increasing movement of viruses around the world poses a major threat to plants growing in cultivated and natural ecosystems. Both generalist and specialist viruses move via trade in plants and plant products. Their potential to damage cultivated plants is well understood, but little attention has been given to the threat such viruses pose to plant biodiversity. To address this, we studied their impact, and that of indigenous viruses, on native plants from a global biodiversity hot spot in an isolated region where agriculture is very recent (plant species, we used introduced generalist and specialist viruses, and indigenous viruses, to inoculate plants of 15 native species belonging to eight families. We also measured resulting losses in biomass and reproductive ability for some host–virus combinations. In addition, we sampled native plants growing over a wide area to increase knowledge of natural infection with introduced viruses. The results suggest that generalist introduced viruses and indigenous viruses from other hosts pose a greater potential threat than introduced specialist viruses to populations of native plants encountered for the first time. Some introduced generalist viruses infected plants in more families than others and so pose a greater potential threat to biodiversity. The indigenous viruses tested were often surprisingly virulent when they infected native plant species they were not adapted to. These results are relevant to managing virus disease in new encounter scenarios at the agro-ecological interface between managed and natural vegetation, and within other disturbed natural vegetation situations. They are also relevant for establishing conservation policies for endangered plant species and avoiding spread of damaging viruses to undisturbed natural vegetation beyond the agro-ecological interface. PMID:24621926

  14. Progress and prospects for phosphoric acid fuel cell power plants

    Energy Technology Data Exchange (ETDEWEB)

    Bonville, L.J.; Scheffler, G.W.; Smith, M.J. [International Fuel Cells Corp., South Windsor, CT (United States)

    1996-12-31

    International Fuel Cells (IFC) has developed the fuel cell power plant as a new, on-site power generation source. IFC`s commercial fuel cell product is the 200-kW PC25{trademark} power plant. To date over 100 PC25 units have been manufactured. Fleet operating time is in excess of one million hours. Individual units of the initial power plant model, the PC25 A, have operated for more than 30,000 hours. The first model {open_quotes}C{close_quotes} power plant has over 10,000 hours of operation. The manufacturing, application and operation of this power plant fleet has established a firm base for design and technology development in terms of a clear understanding of the requirements for power plant reliability and durability. This fleet provides the benchmark against which power plant improvements must be measured.

  15. Ribonuclease activity of buckwheat plant (Fagopyrum esculentum cultivars with different sensitivities to buckwheat burn virus

    Directory of Open Access Journals (Sweden)

    Y. R. Sindarovska

    2014-06-01

    Full Text Available Ribonucleases (RNases are present in base-level amounts in intact plants, but this level is able to increase greatly under stress conditions. The possible cause for such an increase is protection against plant RNA-virus attack. Buckwheat burn virus (BBV is a highly virulent pathogen that belongs to Rhabdoviridae family. In our study, we have analyzed the correlation between RNase activity and resistance of different buckwheat cultivars to BBV infection. Two cultivars, Kara-Dag and Roksolana, with different sensitivities to BBV have been used. Kara-Dag is a cultivar with medium sensitivity to virus and Roksolana is a tolerant cultivar. It has been shown that the base level of RNase activity in Roksolana cultivar was in most cases higher than the corresponding parameter in Kara-Dag cultivar. Both infected and uninfected plants of Roksolana cultivar demonstrated high RNase activity during two weeks. Whereas infected plants of Kara-Dag cultivar demonstrated unstable levels of RNase activity. Significant decline in RNase activity was detected on the 7th day post infection with subsequent gradual increase in RNase activity. Decline of the RNase activity during the first week could promote the virus replication and therefore more successful infection of upper leaves of plants. Unstable levels of RNase activity in infected buckwheat plants may be explained by insufficiency of virus-resistant mechanisms that determines the medium sensitivity of the cultivar to BBV. Thus, plants of buckwheat cultivar having less sensitivity to virus, displayed in general higher RNase activity.

  16. Effect of temperature on the pathogenesis, accumulation of viral and satellite RNAs and on plant proteome in peanut stunt virus and satellite RNA-infected plants

    Directory of Open Access Journals (Sweden)

    Aleksandra eObrępalska-Stęplowska

    2015-10-01

    Full Text Available Temperature is an important environmental factor influencing plant development in natural and diseased conditions. The growth rate of plants grown at 27°C is more rapid than for plants grown at 21°C. Thus, temperature affects the rate of pathogenesis progression in individual plants. We have analyzed the effect of temperature conditions (either 21°C or 27°C during the day on the accumulation rate of the virus and satellite RNA (satRNA in Nicotiana benthamiana plants infected by peanut stunt virus (PSV with and without its satRNA, at four time points. In addition, we extracted proteins from PSV and PSV+satRNA-infected plants harvested at 21 dpi, when disease symptoms began to appear on plants grown at 21°C and were well developed on those grown at 27°C, to assess the proteome profile in infected plants compared to mock-inoculated plants grown at these two temperatures, using 2D-gel electrophoresis and mass spectrometry approaches. The accumulation rate of the viral RNAs and satRNA was more rapid at 27°C at the beginning of the infection and then rapidly decreased in PSV-infected plants. At 21 dpi, PSV and satRNA accumulation was higher at 21°C and had a tendency to increase further. In all studied plants grown at 27°C, we observed a significant drop in the identified proteins participating in photosynthesis and carbohydrate metabolism at the proteome level, in comparison to plants maintained at 21°C. On the other hand, the proteins involved in protein metabolic processes were all more abundant in plants grown at 27°C. This was especially evident when PSV-infected plants were analyzed, where increase in abundance of proteins involved in protein synthesis, degradation, and folding was revealed. In mock-inoculated and PSV-infected plants we found an increase in abundance of the majority of stress-related differently-regulated proteins and those associated with protein metabolism. In contrast, in PSV+satRNA-infected plants the shift in the

  17. Plum pox virus (PPV) genome expression in genetically engineered RNAi plants

    Science.gov (United States)

    An important approach to controlling sharka disease caused by Plum pox virus (PPV) is the development of PPV resistant plants using small interfering RNAs (siRNA) technology. In order to evaluate siRNA induced gene silencing, we studied, based on knowledge of the PPV genome sequence, virus genome t...

  18. RNA virus interference via CRISPR/Cas13a system in plants

    KAUST Repository

    Aman, Rashid; Ali, Zahir; Butt, Haroon; Mahas, Ahmed; Aljedaani, Fatimah R.; Khan, Muhammad Zuhaib; Ding, Shouwei; Mahfouz, Magdy M.

    2018-01-01

    -crRNAs into functional crRNAs.Our data indicate that CRISPR/Cas13a can be used for engineering interference against RNA viruses, providing a potential novel mechanism for RNA-guided immunity against RNA viruses and for other RNA manipulations in plants.

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

    Directory of Open Access Journals (Sweden)

    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.

  20. Extracellular Matrix in Plants and Animals: Hooks and Locks for Viruses

    Directory of Open Access Journals (Sweden)

    Livia Stavolone

    2017-09-01

    Full Text Available The extracellular matrix (ECM of animal and plants cells plays important roles in viral diseases. While in animal cells extracellular matrix components can be exploited by viruses for recognition, attachment and entry, the plant cell wall acts as a physical barrier to viral entry and adds a higher level of difficulty to intercellular movement of viruses. Interestingly, both in plant and animal systems, ECM can be strongly remodeled during virus infection, and the understanding of remodeling mechanisms and molecular players offers new perspectives for therapeutic intervention. This review focuses on the different roles played by the ECM in plant and animal hosts during virus infection with special emphasis on the similarities and differences. Possible biotechnological applications aimed at improving viral resistance are discussed.

  1. Frequency of hepatitis E virus, rotavirus and porcine enteric calicivirus at various stages of pork carcass processing in two pork processing plants.

    Science.gov (United States)

    Jones, Tineke H; Muehlhauser, Victoria

    2017-10-16

    Hepatitis E virus (HEV), rotavirus (RV), and porcine enteric calicivirus (PEC) infections are common in swine and raises concerns about the potential for zoonotic transmission through undercooked meat products. Enteric viruses can potentially contaminate carcasses during meat processing operations. There is a lack of information on the prevalence and control of enteric viruses in the pork processing chain. This study compared the incidence and levels of contamination of hog carcasses with HEV, RV and PEC at different stages of the dressing process. A total of 1000 swabs were collected from 2 pork processing plants on 10 separate occasions over the span of a year. The samples were obtained from random sites on hog carcasses at 4 dressing stages (plant A: bleeding, dehairing, pasteurization, and evisceration; plant B: bleeding, skinning, evisceration, and washing) and from meat cuts. Numbers of genome copies (gc) of HEV, RV and PEC were determined by RT-qPCR. RV and PEC were detected in 100%, and 18% of samples, respectively, after bleeding for plant A and in 98%, and 36% of samples, respectively, after bleeding for plant B. After evisceration, RV and PEC were detected in 21% and 3% of samples, respectively, for plant A and in 1%, and 0% of samples, respectively for plant B. RV and PEC were detected on 1%, and 5% of pork cuts, respectively, for plant A and on 0%, and 0% of pork cuts, respectively, for plant B. HEV was not detected in any pork carcass or retail pork samples from plants A or B. The frequency of PEC and RV on pork is progressively reduced along the pork processing chain but the viruses were not completely eliminated. The findings suggest that consumers could be at risk when consuming undercooked meat contaminated with pathogenic enteric viruses. Crown Copyright © 2017. Published by Elsevier B.V. All rights reserved.

  2. Genome-Wide Search for Host Association Factors during Ovine Progressive Pneumonia Virus Infection.

    Directory of Open Access Journals (Sweden)

    Jesse Thompson

    Full Text Available Ovine progressive pneumonia virus (OPPV is an important virus that causes serious diseases in sheep and goats with a prevalence of 36% in the USA. Although OPPV was discovered more than half of a century ago, little is known about the infection and pathogenesis of this virus. In this report, we used RNA-seq technology to conduct a genome-wide probe for cellular factors that are associated with OPPV infection. A total of approximately 22,000 goat host genes were detected of which 657 were found to have been significantly up-regulated and 889 down-regulated at 12 hours post-infection. In addition to previously known restriction factors from other viral infections, a number of factors which may be specific for OPPV infection were uncovered. The data from this RNA-seq study will be helpful in our understanding of OPPV infection, and also for further study in the prevention and intervention of this viral disease.

  3. Induction of cinnamate 4-hydroxylase and phenylpropanoids in virus-infected cucumber and melon plants.

    OpenAIRE

    Belles Albert, José Mª; López-Gresa, María Pilar; Fayos, J.; Pallás Benet, Vicente; Rodrigo Bravo, Ismael; Conejero Tomás, Vicente

    2008-01-01

    [EN] In the present work, we have looked for the nature of the phenylpropanoids biosynthesized during the plant-pathogen reaction of two systems, Cucumis sativus and Cucumis melo infected with either prunus necrotic ringspot virus (PNRSV) or melon necrotic spot virus (MNSV), respectively. An accumulation of p-coumaric, caffeic and/or ferulic acids was observed in infected plant extracts hydrolysed with P-glucosidase or esterase. Analysis of undigested samples by HPLC/ESI revealed that these c...

  4. Infectious Progression of Canine Distemper Virus from Circulating Cerebrospinal Fluid into the Central Nervous System.

    Science.gov (United States)

    Takenaka, Akiko; Sato, Hiroki; Ikeda, Fusako; Yoneda, Misako; Kai, Chieko

    2016-10-15

    In the current study, we generated recombinant chimeric canine distemper viruses (CDVs) by replacing the hemagglutinin (H) and/or phosphoprotein (P) gene in an avirulent strain expressing enhanced green fluorescent protein (EGFP) with those of a mouse-adapted neurovirulent strain. An in vitro experimental infection indicated that the chimeric CDVs possessing the H gene derived from the mouse-adapted CDV acquired infectivity for neural cells. These cells lack the CDV receptors that have been identified to date (SLAM and nectin-4), indicating that the H protein defines infectivity in various cell lines. The recombinant viruses were administered intracerebrally to 1-week-old mice. Fatal neurological signs of disease were observed only with a recombinant CDV that possessed both the H and P genes of the mouse-adapted strain, similar to the parental mouse-adapted strain, suggesting that both genes are important to drive virulence of CDV in mice. Using this recombinant CDV, we traced the intracerebral propagation of CDV by detecting EGFP. Widespread infection was observed in the cerebral hemispheres and brainstems of the infected mice. In addition, EGFP fluorescence in the brain slices demonstrated a sequential infectious progression in the central nervous system: CDV primarily infected the neuroependymal cells lining the ventricular wall and the neurons of the hippocampus and cortex adjacent to the ventricle, and it then progressed to an extensive infection of the brain surface, followed by the parenchyma and cortex. In the hippocampal formation, CDV spread in a unidirectional retrograde pattern along neuronal processes in the hippocampal formation from the CA1 region to the CA3 region and the dentate gyrus. Our mouse model demonstrated that the main target cells of CDV are neurons in the acute phase and that the virus spreads via neuronal transmission pathways in the hippocampal formation. CDV is the etiological agent of distemper in dogs and other carnivores, and in

  5. One fungus, one name promotes progressive plant pathology.

    Science.gov (United States)

    Wingfield, Michael J; De Beer, Z Wilhelm; Slippers, Bernard; Wingfield, Brenda D; Groenewald, Johannes Z; Lombard, Lorenzo; Crous, Pedro W

    2012-08-01

    The robust and reliable identification of fungi underpins virtually every element of plant pathology, from disease diagnosis to studies of biology, management/control, quarantine and, even more recently, comparative genomics. Most plant diseases are caused by fungi, typically pleomorphic organisms, for which the taxonomy and, in particular, a dual nomenclature system have frustrated and confused practitioners of plant pathology. The emergence of DNA sequencing has revealed cryptic taxa and revolutionized our understanding of relationships in the fungi. The impacts on plant pathology at every level are already immense and will continue to grow rapidly as new DNA sequencing technologies continue to emerge. DNA sequence comparisons, used to resolve a dual nomenclature problem for the first time only 19 years ago, have made it possible to approach a natural classification for the fungi and to abandon the confusing dual nomenclature system. The journey to a one fungus, one name taxonomic reality has been long and arduous, but its time has come. This will inevitably have a positive impact on plant pathology, plant pathologists and future students of this hugely important discipline on which the world depends for food security and plant health in general. This contemporary review highlights the problems of a dual nomenclature, especially its impact on plant pathogenic fungi, and charts the road to a one fungus, one name system that is rapidly drawing near. © 2011 The Authors. Molecular Plant Pathology © 2011 BSPP and Blackwell Publishing Ltd.

  6. Recent progress in SG level control in French PWR plants

    International Nuclear Information System (INIS)

    Parry, A.; Petetrot, J.F.; Vivier, M.J.

    1985-10-01

    Controlling the steam generator (SG) level is of major importance in a large PWR plant. This has led to extensive work on SG computer models. This paper presents results of the comparison between calculations and tests on the first four-loop plant in France. Four-loop plants started up after 1985 will be equipped with digital instead of analog controllers. A new SG level control has been designed and then optimised using the validated SG model. A prototype of this new system has been successfully tested on a three-loop plant. 4 refs

  7. Virus Infection of Plants Alters Pollinator Preference: A Payback for Susceptible Hosts?

    Science.gov (United States)

    Davey, Matthew P.; Bruce, Toby J. A.; Caulfield, John C.; Furzer, Oliver J.; Reed, Alison; Robinson, Sophie I.; Miller, Elizabeth; Davis, Christopher N.; Pickett, John A.; Whitney, Heather M.; Glover, Beverley J.; Carr, John P.

    2016-01-01

    Plant volatiles play important roles in attraction of certain pollinators and in host location by herbivorous insects. Virus infection induces changes in plant volatile emission profiles, and this can make plants more attractive to insect herbivores, such as aphids, that act as viral vectors. However, it is unknown if virus-induced alterations in volatile production affect plant-pollinator interactions. We found that volatiles emitted by cucumber mosaic virus (CMV)-infected tomato (Solanum lycopersicum) and Arabidopsis thaliana plants altered the foraging behaviour of bumblebees (Bombus terrestris). Virus-induced quantitative and qualitative changes in blends of volatile organic compounds emitted by tomato plants were identified by gas chromatography-coupled mass spectrometry. Experiments with a CMV mutant unable to express the 2b RNA silencing suppressor protein and with Arabidopsis silencing mutants implicate microRNAs in regulating emission of pollinator-perceivable volatiles. In tomato, CMV infection made plants emit volatiles attractive to bumblebees. Bumblebees pollinate tomato by ‘buzzing’ (sonicating) the flowers, which releases pollen and enhances self-fertilization and seed production as well as pollen export. Without buzz-pollination, CMV infection decreased seed yield, but when flowers of mock-inoculated and CMV-infected plants were buzz-pollinated, the increased seed yield for CMV-infected plants was similar to that for mock-inoculated plants. Increased pollinator preference can potentially increase plant reproductive success in two ways: i) as female parents, by increasing the probability that ovules are fertilized; ii) as male parents, by increasing pollen export. Mathematical modeling suggested that over a wide range of conditions in the wild, these increases to the number of offspring of infected susceptible plants resulting from increased pollinator preference could outweigh underlying strong selection pressures favoring pathogen resistance

  8. Virus Infection of Plants Alters Pollinator Preference: A Payback for Susceptible Hosts?

    Directory of Open Access Journals (Sweden)

    Simon C Groen

    2016-08-01

    Full Text Available Plant volatiles play important roles in attraction of certain pollinators and in host location by herbivorous insects. Virus infection induces changes in plant volatile emission profiles, and this can make plants more attractive to insect herbivores, such as aphids, that act as viral vectors. However, it is unknown if virus-induced alterations in volatile production affect plant-pollinator interactions. We found that volatiles emitted by cucumber mosaic virus (CMV-infected tomato (Solanum lycopersicum and Arabidopsis thaliana plants altered the foraging behaviour of bumblebees (Bombus terrestris. Virus-induced quantitative and qualitative changes in blends of volatile organic compounds emitted by tomato plants were identified by gas chromatography-coupled mass spectrometry. Experiments with a CMV mutant unable to express the 2b RNA silencing suppressor protein and with Arabidopsis silencing mutants implicate microRNAs in regulating emission of pollinator-perceivable volatiles. In tomato, CMV infection made plants emit volatiles attractive to bumblebees. Bumblebees pollinate tomato by 'buzzing' (sonicating the flowers, which releases pollen and enhances self-fertilization and seed production as well as pollen export. Without buzz-pollination, CMV infection decreased seed yield, but when flowers of mock-inoculated and CMV-infected plants were buzz-pollinated, the increased seed yield for CMV-infected plants was similar to that for mock-inoculated plants. Increased pollinator preference can potentially increase plant reproductive success in two ways: i as female parents, by increasing the probability that ovules are fertilized; ii as male parents, by increasing pollen export. Mathematical modeling suggested that over a wide range of conditions in the wild, these increases to the number of offspring of infected susceptible plants resulting from increased pollinator preference could outweigh underlying strong selection pressures favoring pathogen

  9. Engineering Plant Immunity: Using CRISPR/Cas9 to Generate Virus Resistance

    KAUST Repository

    Zaidi, Syed Shan-e-Ali

    2016-11-08

    Plant viruses infect many economically important crops, including wheat, cotton, maize, cassava, and other vegetables. These viruses pose a serious threat to agriculture worldwide, as decreases in cropland area per capita may cause production to fall short of that required to feed the increasing world population. Under these circumstances, conventional strategies can fail to control rapidly evolving and emerging plant viruses. Genome-engineering strategies have recently emerged as promising tools to introduce desirable traits in many eukaryotic species, including plants. Among these genome engineering technologies, the CRISPR (clustered regularly interspaced palindromic repeats)/CRISPR-associated 9 (CRISPR/Cas9) system has received special interest because of its simplicity, efficiency, and reproducibility. Recent studies have used CRISPR/Cas9 to engineer virus resistance in plants, either by directly targeting and cleaving the viral genome, or by modifying the host plant genome to introduce viral immunity. Here, we briefly describe the biology of the CRISPR/Cas9 system and plant viruses, and how different genome engineering technologies have been used to target these viruses. We further describe the main findings from recent studies of CRISPR/Cas9-mediated viral interference and discuss how these findings can be applied to improve global agriculture. We conclude by pinpointing the gaps in our knowledge and the outstanding questions regarding CRISPR/Cas9-mediated viral immunity.

  10. Engineering Plant Immunity: Using CRISPR/Cas9 to Generate Virus Resistance

    KAUST Repository

    Zaidi, Syed Shan-e-Ali; Tashkandi, Manal; Mansoor, Shahid; Mahfouz, Magdy M.

    2016-01-01

    Plant viruses infect many economically important crops, including wheat, cotton, maize, cassava, and other vegetables. These viruses pose a serious threat to agriculture worldwide, as decreases in cropland area per capita may cause production to fall short of that required to feed the increasing world population. Under these circumstances, conventional strategies can fail to control rapidly evolving and emerging plant viruses. Genome-engineering strategies have recently emerged as promising tools to introduce desirable traits in many eukaryotic species, including plants. Among these genome engineering technologies, the CRISPR (clustered regularly interspaced palindromic repeats)/CRISPR-associated 9 (CRISPR/Cas9) system has received special interest because of its simplicity, efficiency, and reproducibility. Recent studies have used CRISPR/Cas9 to engineer virus resistance in plants, either by directly targeting and cleaving the viral genome, or by modifying the host plant genome to introduce viral immunity. Here, we briefly describe the biology of the CRISPR/Cas9 system and plant viruses, and how different genome engineering technologies have been used to target these viruses. We further describe the main findings from recent studies of CRISPR/Cas9-mediated viral interference and discuss how these findings can be applied to improve global agriculture. We conclude by pinpointing the gaps in our knowledge and the outstanding questions regarding CRISPR/Cas9-mediated viral immunity.

  11. One fungus, one name promotes progressive plant pathology

    NARCIS (Netherlands)

    Wingfield, M.J.; De Beer, Z.W.; Slippers, B.; Wingfield, B.D.; Groenewald, J.Z.; Lombard, L.; Crous, P.W.

    2011-01-01

    The robust and reliable identification of fungi underpins virtually every element of plant pathology, from disease diagnosis to studies of biology, management/control, quarantine and, even more recently, comparative genomics. Most plant diseases are caused by fungi, typically pleomorphic organisms,

  12. One fungus, one name promotes progressive plant pathology

    NARCIS (Netherlands)

    Wingfield, M.J.; Beer, de Z.W.; Slippers, B.; Wingfield, B.D.; Groenewald, J.Z.; Lombard, L.; Crous, P.W.

    2012-01-01

    The robust and reliable identification of fungi underpins virtually every element of plant pathology, from disease diagnosis to studies of biology, management/control, quarantine and, even more recently, comparative genomics. Most plant diseases are caused by fungi, typically pleomorphic organisms,

  13. Infection of Melanoplus sanguinipes grasshoppers following ingestion of rangeland plant species harboring vesicular stomatitis virus.

    Science.gov (United States)

    Drolet, Barbara S; Stuart, Melissa A; Derner, Justin D

    2009-05-01

    Knowledge of the many mechanisms of vesicular stomatitis virus (VSV) transmission is critical for understanding of the epidemiology of sporadic disease outbreaks in the western United States. Migratory grasshoppers [Melanoplus sanguinipes (Fabricius)] have been implicated as reservoirs and mechanical vectors of VSV. The grasshopper-cattle-grasshopper transmission cycle is based on the assumptions that (i) virus shed from clinically infected animals would contaminate pasture plants and remain infectious on plant surfaces and (ii) grasshoppers would become infected by eating the virus-contaminated plants. Our objectives were to determine the stability of VSV on common plant species of U.S. Northern Plains rangelands and to assess the potential of these plant species as a source of virus for grasshoppers. Fourteen plant species were exposed to VSV and assayed for infectious virus over time (0 to 24 h). The frequency of viable virus recovery at 24 h postexposure was as high as 73%. The two most common plant species in Northern Plains rangelands (western wheatgrass [Pascopyrum smithii] and needle and thread [Hesperostipa comata]) were fed to groups of grasshoppers. At 3 weeks postfeeding, the grasshopper infection rate was 44 to 50%. Exposure of VSV to a commonly used grasshopper pesticide resulted in complete viral inactivation. This is the first report demonstrating the stability of VSV on rangeland plant surfaces, and it suggests that a significant window of opportunity exists for grasshoppers to ingest VSV from contaminated plants. The use of grasshopper pesticides on pastures would decrease the incidence of a virus-amplifying mechanical vector and might also decontaminate pastures, thereby decreasing the inter- and intraherd spread of VSV.

  14. The potential of plant viruses to promote genotypic diversity via genotype x environment interactions

    DEFF Research Database (Denmark)

    van Mölken, Tamara; Stuefer, Josef F.

    2011-01-01

    † Background and Aims Genotype by environment (G × E) interactions are important for the long-term persistence of plant species in heterogeneous environments. It has often been suggested that disease is a key factor for the maintenance of genotypic diversity in plant populations. However, empirical...... and the G × E interactions were examined with respect to genotypespecific plant responses to WClMV infection. Thus, the environment is defined as the presence or absence of the virus. † Key Results WClMV had a negative effect on plant performance as shown by a decrease in biomass and number of ramets...... evidence for this contention is scarce. Here virus infection is proposed as a possible candidate for maintaining genotypic diversity in their host plants. † Methods The effects of White clover mosaic virus (WClMV) on the performance and development of different Trifolium repens genotypes were analysed...

  15. An improved electrochemiluminescence polymerase chain reaction method for highly sensitive detection of plant viruses

    International Nuclear Information System (INIS)

    Tang Yabing; Xing Da; Zhu Debin; Liu Jinfeng

    2007-01-01

    Recently, we have reported an electrochemiluminescence polymerase chain reaction (ECL-PCR) method for detection of genetically modified organisms. The ECL-PCR method was further improved in the current study by introducing a multi-purpose nucleic acid sequence that was specific to the tris(bipyridine) ruthenium (TBR) labeled probe, into the 5' terminal of the primers. The method was applied to detect plant viruses. Conserved sequence of the plant viruses was amplified by PCR. The product was hybridized with a biotin labeled probe and a TBR labeled probe. The hybridization product was separated by streptavidin-coated magnetic beads, and detected by measuring the ECL signals of the TBR labeled. Under the optimized conditions, the experiment results show that the detection limit is 50 fmol of PCR products, and the signal-to-noise ratio is in excess of 14.6. The method was used to detect banana streak virus, banana bunchy top virus, and papaya leaf curl virus. The experiment results show that this method could reliably identity viruses infected plant samples. The improved ECL-PCR approach has higher sensitivity and lower cost than previous approach. It can effectively detect the plant viruses with simplicity, stability, and high sensitivity

  16. Marker Removal in Transgenic Plants Using Cre Recombinase Delivered with Potato Virus X.

    Science.gov (United States)

    Kopertekh, Lilya; Schiemann, Joachim

    2017-01-01

    In this chapter we present an alternative method to develop marker-free transgenic plants. It makes use of the Cre/loxP recombination system from bacteriophage P1 and consists of two essential components. The first component is the transgenic plant containing a loxP-flanked marker gene. The second component is a cre transient expression vector based on potato virus X. The great benefit of this transient delivery method consists in the avoidance of stable integration of the cre recombinase gene into the plant genome. Upon infection of the loxP-target plant with PVX-Cre, the virus spreads systemically through the plant and causes the recombinase-mediated excision of the marker gene. Marker-free transgenic loci can be transmitted to the progeny by plant regeneration from PVX-Cre systemically infected leaves or self-pollination of virus-infected plants. The protocol covers generation of loxP-target transgenic plants, PVX-mediated delivery of Cre recombinase protein, phenotypic and molecular analysis of recombination events, and transmission of marker-free transgenic loci to the next generation. The transient expression system described in this chapter can be adapted for marker gene removal in other plant species that are amenable for virus infection.

  17. Genetic determinism and evolutionary reconstruction of a host jump in a plant virus

    DEFF Research Database (Denmark)

    Vassilakos, Nikon; Simon, Vincent; Tzima, Aliki

    2016-01-01

    In spite of their widespread occurrence, only few host jumps by plant viruses have been evidenced and the molecular bases of even fewer have been determined. A combination of three independent approaches, 1) experimental evolution followed by reverse genetics analysis, 2) positive selection...... analysis, and 3) locus-by-locus analysis of molecular variance (AMOVA) allowed reconstructing the Potato virus Y (PVY; genus Potyvirus, family Potyviridae) jump to pepper (Capsicum annuum), probably from other solanaceous plants. Synthetic chimeras between infectious cDNA clones of two PVY isolates...... independently and conferred adaptation to C. annuum. In addition to increasing our knowledge of host jumps in plant viruses, this study illustrates also the efficiency of locus-by-locus AMOVA and combined approaches to identify adaptive mutations in the genome of RNA viruses....

  18. Spicing Up the N Gene: F. O. Holmes and Tobacco mosaic virus Resistance in Capsicum and Nicotiana Plants.

    Science.gov (United States)

    Scholthof, Karen-Beth G

    2017-02-01

    One of the seminal events in plant pathology was the discovery by Francis O. Holmes that necrotic local lesions induced on certain species of Nicotiana following rub-inoculation of Tobacco mosaic virus (TMV) was due to a specific interaction involving a dominant host gene (N). From this, Holmes had an idea that if the N gene from N. glutinosa was introgressed into susceptible tobacco, the greatly reduced titer of TMV would, by extension, prevent subsequent infection of tomato and pepper plants by field workers whose hands were contaminated with TMV from their use of chewing and smoking tobacco. The ultimate outcome has many surprising twists and turns, including Holmes' failure to obtain fertile crosses of N. glutinosa × N. tabacum after 3 years of intensive work. Progress was made with N. digluta, a rare amphidiploid that was readily crossed with N. tabacum. And, importantly, the first demonstration by Holmes of the utility of interspecies hybridization for virus resistance was made with Capsicum (pepper) species with the identification of the L gene in Tabasco pepper, that he introgressed into commercial bell pepper varieties. Holmes' findings are important as they predate Flor's gene-for-gene hypothesis, show the use of interspecies hybridization for control of plant pathogens, and the use of the local lesion as a bioassay to monitor resistance events in crop plants.

  19. Detection and sequencing of Potato virus Y (PVY and Potato leafroll virus (PLRV in a volunteer plant of Solanum tuberosum L. cv. Diacol-Capiro

    Directory of Open Access Journals (Sweden)

    Héctor Camilo Medina Cárdenas

    2017-10-01

    Full Text Available Viral diseases are among the most limiting factors in the production of potato in Colombia and the rest of the world. The best strategy to control plant viruses consists on the use of certified seed tubers, control of arthropod vectors and the use of adequate crop management practices that reduce mechanical transmission and the presence of viral reservoirs like weeds and volun-teer plants. However, the successful implementation of these practices relies on the availability of highly sensitive techniques that allow for the asymptomatic detection of viruses. In this work, we tested the performance of Next-generation sequencing (NGS and real time RT-PCR (RT-qPCR on a single volunteer potato plant (cv. Diacol-Capiro growing naturally in a seed-tuber storage facility in Yarumal (Antioquia. Our NGS results demonstrate a mixed infection with Potato virus Y (PVY and Potato leafroll virus (PLRV. RT-qPCR was performed in roots, main stolons, crown (root collar and upper, middle and lower leaves using specific primers for PVY, PLRV, Potato virus S (PVS, Potato virus V (PVV, Potato virus X (PVX and Potato yellow vein virus (PYVV. Only PVY and PLRV were detected in good agreement with the NGS data. This work demonstrates the use-fulness of both techniques for supporting integrated management of plant viruses in potato, in-cluding virus detection in natural reservoirs such as volunteer plants and weeds.

  20. Progress and challenges for abiotic stress proteomics of crop plants.

    Science.gov (United States)

    Barkla, Bronwyn J; Vera-Estrella, Rosario; Pantoja, Omar

    2013-06-01

    Plants are continually challenged to recognize and respond to adverse changes in their environment to avoid detrimental effects on growth and development. Understanding the mechanisms that crop plants employ to resist and tolerate abiotic stress is of considerable interest for designing agriculture breeding strategies to ensure sustainable productivity. The application of proteomics technologies to advance our knowledge in crop plant abiotic stress tolerance has increased dramatically in the past few years as evidenced by the large amount of publications in this area. This is attributed to advances in various technology platforms associated with MS-based techniques as well as the accessibility of proteomics units to a wider plant research community. This review summarizes the work which has been reported for major crop plants and evaluates the findings in context of the approaches that are widely employed with the aim to encourage broadening the strategies used to increase coverage of the proteome. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. [Carbon isotope fractionation in plants]: Annual technical progress report

    International Nuclear Information System (INIS)

    O'Leary, M.H.

    1988-01-01

    Plants fractionate carbon isotopes during photosynthesis in ways which reflect photosynthetic pathway and environment. The fractionation is product of contributions from diffusion, carboxylation and other factors which can be understood using models which have been developed in our work. The object of our work is to use this fractionation to learn about the factors which control the efficiency of photosynthesis. Unlike previous studies, we do not rely principally on combustion methods, but instead develop more specific methods with substantially higher resolving power. We have recently developed a new short-term method for studying carbon isotope fractionation which promises to provide a level of detail about temperature, species, and light intensity effects on photosynthesis which has not been available until now. We are studying the isotopic compositions of metabolites (particularly aspartic acid) in C 3 plants in order to determine the role of phosphoenolpyruvate carboxylase in C 3 photosynthesis. We are studying the relative roles of diffusion and carboxylation in nocturnal CO 2 fixation in CAM plants. We are studying the use of isotopic content as an index of water-use efficiency in C 3 plants. We are developing new methods for studying carbon metabolism in plants. 3 refs

  2. The potential of virus-induced gene silencing for speeding up functional characterization of plant genes

    NARCIS (Netherlands)

    Benedito, V.A.; Visser, P.B.; Angenent, G.C.; Krens, F.A.

    2004-01-01

    Virus-induced gene silencing (VIGS) has been shown to be of great potential in plant reverse genetics. Advantages of VIGS over other approaches, such as T-DNA or transposon tagging, include the circumvention of plant transformation, methodological simplicity and robustness, and speedy results. These

  3. Inactivated recombinant plant virus protects dogs from a lethal challenge with canine parvovirus

    DEFF Research Database (Denmark)

    Langeveld, J.P.M.; Brennan, F.R.; Martinez-Torrecuadrada, J.L.

    2001-01-01

    A vaccine based upon a recombinant plant virus (CPMV-PARVO1), displaying a peptide derived from the VP2 capsid protein of canine parvovirus (CPV), has previously been described. To date, studies with the vaccine have utilized viable plant chimaeric particles (CVPs). In this study, CPMV-PARVO1...

  4. Complementation and recombination between alfalfa mosaic virus RNA3 mutants in tobacco plants

    NARCIS (Netherlands)

    van der Kuyl, A. C.; Neeleman, L.; Bol, J. F.

    1991-01-01

    Deletions were made in an infectious cDNA clone of alfalfa mosaic virus (AIMV) RNA3 and the replication of RNA transcripts of these cDNAs was studied in tobacco plants transformed with AIMV replicase genes (P12 plants). Previously, we found that deletions in the P3 gene did not affect accumulation

  5. Contributions of plant breeding in Brazil – progress and perspectives

    Directory of Open Access Journals (Sweden)

    Magno Antonio Patto Ramalho

    2012-12-01

    Full Text Available Agribusiness is fundamental for the Brazilian economy. This has become possible due to the use of science and technology in agriculture in the last 35 years. Among the technologies, the use of improved cultivars stands out. This article presents the situation of the species grown in the country in recent years and the contribution of genetic plant breeding to the performance of these species. Challenges multiplied because of populational growth associated with the ever-growing concern of society with the environment. Breeders of the present and future must base plant selection in the field on new technologies so that it is possible to meet demand.

  6. Plant-derived chimeric virus particles for the diagnosis of primary Sjögren syndrome

    Directory of Open Access Journals (Sweden)

    Elisa eTinazzi

    2015-12-01

    Full Text Available Plants are ideal for the production of protein-based nanomaterials because they synthesize and assemble complex multimeric proteins that cannot be expressed efficiently using other platforms. Plant viruses can be thought of as self-replicating proteinaceous nanomaterials generally stable and easily produced in high titers. We used Potato virus X (PVX chimeric virus particles (CVPs and Cowpea mosaic virus (CPMV empty virus-like particles (eVLPs to display a linear peptide (lipo derived from human lipocalin , which is immunodominant in Sjögren’s syndrome (SjS and is thus recognized by autoantibodies in SjS patient serum. These virus-derived nanoparticles (VNPs were thus used to develop a diagnostic assay for SjS based on a direct enzyme linked immunosorbent assay (ELISA format. We found that PVX-lipo formulations were more sensitive than the chemically synthesized immunodominant peptide and equally specific when used to distinguish between healthy individuals and SjS patients. Our novel assay therefore allows the diagnosis of SjS using a simple, low-invasive serum test, contrasting with the invasive labial biopsy required for current tests. Our results demonstrate that nanomaterials based on plant viruses can be used as diagnostic reagents for SjS, and could also be developed for the diagnosis of other diseases.

  7. Delayed Disease Progression in Cynomolgus Macaques Infected with Ebola Virus Makona Strain.

    Science.gov (United States)

    Marzi, Andrea; Feldmann, Friederike; Hanley, Patrick W; Scott, Dana P; Günther, Stephan; Feldmann, Heinz

    2015-10-01

    In late 2013, the largest documented outbreak of Ebola hemorrhagic fever started in Guinea and has since spread to neighboring countries, resulting in almost 27,000 cases and >11,000 deaths in humans. In March 2014, Ebola virus (EBOV) was identified as the causative agent. This study compares the pathogenesis of a new EBOV strain, Makona, which was isolated in Guinea in 2014 with the prototype strain from the 1976 EBOV outbreak in the former Zaire. Both strains cause lethal disease in cynomolgus macaques with similar pathologic changes and hallmark features of Ebola hemorrhagic fever. However, disease progression was delayed in EBOV-Makona-infected animals, suggesting decreased rather than increased virulence of this most recent EBOV strain.

  8. Imaging of human T-lymphotropic virus type I-associated chronic progressive myeloneuropathies

    International Nuclear Information System (INIS)

    Alcindor, F.; Valderrama, R.; Canavaggio, M.; Lee, H.; Katz, A.; Montesinos, C.; Madrid, R.E.; Merino, R.R.; Pipia, P.A.

    1992-01-01

    We studied magnetic resonance imaging (MRI) of the head and cervical spine and CT of the head in 46 patients (14 men, 32 women) with chronic progressive myeloneuropathy. The findings were correlated with human T-lymphotropic virus type I (HTLV-I) serology, race, country of origin, and age. We found a female predominance of 2:1. Most patients were aged between 30 and 50 years, and most were Caribbean immigrants and black. There were 9 men and 17 women with blood antibody titers to HTLV-I and 7 mem and 15 women with cerebrospinal fluid (CSF) titers. All patients with virus or antibodies in blood or CSF were Caribbean immigrants or black. T2-weighted cranial MRI showed scattered areas of high signal intensity in the cerebral white matter, usually in the periventricular and subcortical areas, but not in the posterior cranial fossa. Cranial CT revealed periventricular low density areas, ventricular enlargement, and atrophy MRI of the cervical spine showed atrophy of the cord. Myelography was normal in all 15 patients examined. No imaging differences were observed between the HTLV-I-positive and -negative patients. These findings, although consistent with demyelination, are not specific. (orig.)

  9. Imaging of human T-lymphotropic virus type I-associated chronic progressive myeloneuropathies

    Energy Technology Data Exchange (ETDEWEB)

    Alcindor, F. (Dept. of Neurology, State Univ. of New York, Health Science Center, Brooklyn, NY (United States)); Valderrama, R. (Dept. of Neurology, State Univ. of New York, Health Science Center, Brooklyn, NY (United States)); Canavaggio, M. (Abbott Labs., North Chicago, IL (United States)); Lee, H. (Abbott Labs., North Chicago, IL (United States)); Katz, A. (Dept. of Neurology, State Univ. of New York, Health Science Center, Brooklyn, NY (United States)); Montesinos, C. (Beth Israel Medical Center, Dept. of Neurology and Clinical Electrophysiology, New York, NY (United States)); Madrid, R.E. (New York State Office of Mental Retardation and Developmental Disabilities, Inst. for Basic Research in Developmental Disabilities, NY (United States)); Merino, R.R. (Beth Israel Medical Center, Dept. of Neurology and Clinical Electrophysiology, New York, NY (United States)); Pipia, P.A. (Dept. of Neurology, State Univ. of New York, Health Science Center, Brooklyn, NY (United States))

    1992-12-01

    We studied magnetic resonance imaging (MRI) of the head and cervical spine and CT of the head in 46 patients (14 men, 32 women) with chronic progressive myeloneuropathy. The findings were correlated with human T-lymphotropic virus type I (HTLV-I) serology, race, country of origin, and age. We found a female predominance of 2:1. Most patients were aged between 30 and 50 years, and most were Caribbean immigrants and black. There were 9 men and 17 women with blood antibody titers to HTLV-I and 7 mem and 15 women with cerebrospinal fluid (CSF) titers. All patients with virus or antibodies in blood or CSF were Caribbean immigrants or black. T2-weighted cranial MRI showed scattered areas of high signal intensity in the cerebral white matter, usually in the periventricular and subcortical areas, but not in the posterior cranial fossa. Cranial CT revealed periventricular low density areas, ventricular enlargement, and atrophy MRI of the cervical spine showed atrophy of the cord. Myelography was normal in all 15 patients examined. No imaging differences were observed between the HTLV-I-positive and -negative patients. These findings, although consistent with demyelination, are not specific. (orig.)

  10. Nucleic acid hybridization and radioimmunoassay techniques for studying the interrelationships among the progressive pneumonia viruses of sheep

    International Nuclear Information System (INIS)

    Weiss, M.J.

    1976-01-01

    In Section I of this thesis, experiments were performed to determine if three representative ''slow'' viruses of sheep VV, MV and PPV replicate by way of a DNA ''provirus'' in a manner similar to the RNA tumor viruses. The approach used was to determine if unique virus-specific DNA sequences not present in normal cells could be detected in the DNA of infected cell cultures. The results presented demonstrate that infection by VV, MV and PPV results in the synthesis of proviral DNA. Sections II and III examine the similarities among VV, MV and PPV. In Section II, the RNA genomes of these viruses were compared by nucleic acid hybridization. The homology among these viral RNAs was determined from the extensive competition of homologous viral RNA-cDNA hybrids by heterologous RNA and from the thermal stability of homologous and heterologous RNA-cDNA hybrids. The 70S RNAs of visna and maedi virus were indistinguishable but only partially homologous to that of progressive pneumonia virus. Section III describes the purification of the major internal protein component of VV, p27, the development of a radioimmunoassay to study its antigenic relatedness to the corresponding proteins of PPV and MV, and its use in the detection of cross-reacting proteins in progressive pneumonia virus infected sheep lung. The ability to detect unique virus-related DNA sequences and viral antigens in infected sheep tissues makes it now feasible to search for slow virus related DNA sequences and/or antigens in human diseases which bear resemblance to the slow diseases of sheep

  11. Plum pox virus capsid protein suppresses plant pathogen-associated molecular pattern (PAMP)-triggered immunity.

    Science.gov (United States)

    Nicaise, Valerie; Candresse, Thierry

    2017-08-01

    The perception of pathogen-associated molecular patterns (PAMPs) by immune receptors launches defence mechanisms referred to as PAMP-triggered immunity (PTI). Successful pathogens must suppress PTI pathways via the action of effectors to efficiently colonize their hosts. So far, plant PTI has been reported to be active against most classes of pathogens, except viruses, although this defence layer has been hypothesized recently as an active part of antiviral immunity which needs to be suppressed by viruses for infection success. Here, we report that Arabidopsis PTI genes are regulated upon infection by viruses and contribute to plant resistance to Plum pox virus (PPV). Our experiments further show that PPV suppresses two early PTI responses, the oxidative burst and marker gene expression, during Arabidopsis infection. In planta expression of PPV capsid protein (CP) was found to strongly impair these responses in Nicotiana benthamiana and Arabidopsis, revealing its PTI suppressor activity. In summary, we provide the first clear evidence that plant viruses acquired the ability to suppress PTI mechanisms via the action of effectors, highlighting a novel strategy employed by viruses to escape plant defences. © 2016 BSPP AND JOHN WILEY & SONS LTD.

  12. Creation of transgenic rice plants producing small interfering RNA of Rice tungro spherical virus.

    Science.gov (United States)

    Le, Dung Tien; Chu, Ha Duc; Sasaya, Takahide

    2015-01-01

    Rice tungro spherical virus (RTSV), also known as Rice waika virus, does not cause visible symptoms in infected rice plants. However, the virus plays a critical role in spreading Rice tungro bacilliform virus (RTBV), which is the major cause of severe symptoms of rice tungro disease. Recent studies showed that RNA interference (RNAi) can be used to develop virus-resistance transgenic rice plants. In this report, we presented simple procedures and protocols needed for the creation of transgenic rice plants capable of producing small interfering RNA specific against RTSV sequences. Notably, our study showed that 60 out of 64 individual hygromycin-resistant lines (putative transgenic lines) obtained through transformation carried transgenes designed for producing hairpin double-stranded RNA. Northern blot analyses revealed the presence of small interfering RNA of 21- to 24-mer in 46 out of 56 confirmed transgenic lines. Taken together, our study indicated that transgenic rice plants carrying an inverted repeat of 500-bp fragments encoding various proteins of RTSV can produce small interfering RNA from the hairpin RNA transcribed from that transgene. In light of recent studies with other viruses, it is possible that some of these transgenic rice lines might be resistant to RTSV.

  13. Within-host spatiotemporal dynamics of plant virus infection at the cellular level.

    Directory of Open Access Journals (Sweden)

    Nicolas Tromas

    2014-02-01

    Full Text Available A multicellular organism is not a monolayer of cells in a flask; it is a complex, spatially structured environment, offering both challenges and opportunities for viruses to thrive. Whereas virus infection dynamics at the host and within-cell levels have been documented, the intermediate between-cell level remains poorly understood. Here, we used flow cytometry to measure the infection status of thousands of individual cells in virus-infected plants. This approach allowed us to determine accurately the number of cells infected by two virus variants in the same host, over space and time as the virus colonizes the host. We found a low overall frequency of cellular infection (<0.3, and few cells were coinfected by both virus variants (<0.1. We then estimated the cellular contagion rate (R, the number of secondary infections per infected cell per day. R ranged from 2.43 to values not significantly different from zero, and generally decreased over time. Estimates of the cellular multiplicity of infection (MOI, the number of virions infecting a cell, were low (<1.5. Variance of virus-genotype frequencies increased strongly from leaf to cell levels, in agreement with a low MOI. Finally, there were leaf-dependent differences in the ease with which a leaf could be colonized, and the number of virions effectively colonizing a leaf. The modeling of infection patterns suggests that the aggregation of virus-infected cells plays a key role in limiting spread; matching the observation that cell-to-cell movement of plant viruses can result in patches of infection. Our results show that virus expansion at the between-cell level is restricted, probably due to the host environment and virus infection itself.

  14. Evolution of plant virus movement proteins from the 30K superfamily and of their homologs integrated in plant genomes

    Energy Technology Data Exchange (ETDEWEB)

    Mushegian, Arcady R., E-mail: mushegian2@gmail.com [Division of Molecular and Cellular Biosciences, National Science Foundation, 4201 Wilson Boulevard, Arlington, VA 22230 (United States); Elena, Santiago F., E-mail: sfelena@ibmcp.upv.es [Instituto de Biología Molecular y Celular de Plantas, CSIC-UPV, 46022 València (Spain); The Santa Fe Institute, Santa Fe, NM 87501 (United States)

    2015-02-15

    Homologs of Tobacco mosaic virus 30K cell-to-cell movement protein are encoded by diverse plant viruses. Mechanisms of action and evolutionary origins of these proteins remain obscure. We expand the picture of conservation and evolution of the 30K proteins, producing sequence alignment of the 30K superfamily with the broadest phylogenetic coverage thus far and illuminating structural features of the core all-beta fold of these proteins. Integrated copies of pararetrovirus 30K movement genes are prevalent in euphyllophytes, with at least one copy intact in nearly every examined species, and mRNAs detected for most of them. Sequence analysis suggests repeated integrations, pseudogenizations, and positive selection in those provirus genes. An unannotated 30K-superfamily gene in Arabidopsis thaliana genome is likely expressed as a fusion with the At1g37113 transcript. This molecular background of endopararetrovirus gene products in plants may change our view of virus infection and pathogenesis, and perhaps of cellular homeostasis in the hosts. - Highlights: • Sequence region shared by plant virus “30K” movement proteins has an all-beta fold. • Most euphyllophyte genomes contain integrated copies of pararetroviruses. • These integrated virus genomes often include intact movement protein genes. • Molecular evidence suggests that these “30K” genes may be selected for function.

  15. 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.

  16. Protection of melon plants against Cucumber mosaic virus infection ...

    African Journals Online (AJOL)

    Adhab

    The broad host range of CMV and its ability to be transmitted by aphids .... development of obvious yellow color in ELISA micro plate wells. The mean ... hosts harbor the virus in asymptomatic infection (Table. 1). ... Aster subulatus Michx.

  17. Progressive building methods in nuclear power plant construction

    International Nuclear Information System (INIS)

    Sikura, V.

    1980-01-01

    A detailed description is given of the new prospective technologies used in the construction of the Bohunice V-1 nuclear power plant. They include the use of steel and large-area forms, the use of profile sheets as a substitute for forms, assembled raw partitions, wall shells consisting of clamped porous concrete slabs, assembled roof shells, special finish of concrete walls, bearing wall deep foundation, the use of modern building machinery for concreting, reinforcing and welding works. (M.S.)

  18. Contributions of plant breeding in Brazil: progress and perspectives

    OpenAIRE

    Ramalho, Magno Antonio Patto; Dias, Luiz Antônio dos Santos; Carvalho, Bruna Line

    2012-01-01

    Agribusiness is fundamental for the Brazilian economy. This has become possible due to the use of science and technology in agriculture in the last 35 years. Among the technologies, the use of improved cultivars stands out. This article presents the situation of the species grown in the country in recent years and the contribution of genetic plant breeding to the performance of these species. Challenges multiplied because of populational growth associated with the ever-growing concern of soci...

  19. Plant invasion science in protected areas: progress and priorities

    Czech Academy of Sciences Publication Activity Database

    Foxcroft, L. C.; Pyšek, Petr; Richardson, D. M.; Genovesi, P.; MacFadyen, S.

    2017-01-01

    Roč. 19, č. 5 (2017), s. 1353-1378 ISSN 1387-3547 R&D Projects: GA ČR GB14-36079G Grant - others:AV ČR(CZ) AP1002 Program:Akademická prémie - Praemium Academiae Institutional support: RVO:67985939 Keywords : plant invasions * global patterns * protected areas Subject RIV: EH - Ecology, Behaviour OBOR OECD: Biodiversity conservation Impact factor: 2.473, year: 2016

  20. Studies on virus-induced cell fusion. Progress report, August 1, 1975--April 30, 1976. [Herpes simplex

    Energy Technology Data Exchange (ETDEWEB)

    Person, S.

    1976-01-01

    Progress is reported on the following research projects: mechanism of cell fusion induced by fusion-causing mutants of herpes simplex virus type I; quantitative assays for kinetics of cell fusion; neutral sphingoglycolipids in wild type and mutant infected cells; effects of alteration in oligosaccharide metabolism on cell fusion; and blocking of fusion by ..beta..-galactosidase and NH/sub 4/Cl. (HLW)

  1. Heterologous RNA-silencing suppressors from both plant- and animal-infecting viruses support plum pox virus infection.

    Science.gov (United States)

    Maliogka, Varvara I; Calvo, María; Carbonell, Alberto; García, Juan Antonio; Valli, Adrian

    2012-07-01

    HCPro, the RNA-silencing suppressor (RSS) of viruses belonging to the genus Potyvirus in the family Potyviridae, is a multifunctional protein presumably involved in all essential steps of the viral infection cycle. Recent studies have shown that plum pox potyvirus (PPV) HCPro can be replaced successfully by cucumber vein yellowing ipomovirus P1b, a sequence-unrelated RSS from a virus of the same family. In order to gain insight into the requirement of a particular RSS to establish a successful potyviral infection, we tested the ability of different heterologous RSSs from both plant- and animal-infecting viruses to substitute for HCPro. Making use of engineered PPV chimeras, we show that PPV HCPro can be replaced functionally by some, but not all, unrelated RSSs, including the NS1 protein of the mammal-infecting influenza A virus. Interestingly, the capacity of a particular RSS to replace HCPro does not correlate strictly with its RNA silencing-suppression strength. Altogether, our results suggest that not all suppression strategies are equally suitable for efficient escape of PPV from the RNA-silencing machinery. The approach followed here, based on using PPV chimeras in which an under-consideration RSS substitutes for HCPro, could further help to study the function of diverse RSSs in a 'highly sensitive' RNA-silencing context, such as that taking place in plant cells during the process of a viral infection.

  2. Isolation of viruses from drinking water at the Point-Viau water treatment plant

    Energy Technology Data Exchange (ETDEWEB)

    Payment, P.

    1981-04-01

    Viruses were isolated from every sample of raw (100 L) and treated (1000 L) water collected at a water treatment plant drawing sewage-contaminated river water. Few plaque-forming isolates were formed but cytopathogenic viruses were isolated as frequently in drinking water as in raw water. In drinking water some samples contained more than 1 cytopathogenic unit per litre, but most contained 1-10/100 L. These viruses had not been inactivated or removed by prechlorination, flocculation, filtration, ozonation, and postchlorination. There were no coliforms present and a residual chlorine level had been maintained. Poliovirus type 1 was a frequent isolate but many isolates were nonpoliovirus. The presence of these viruses in drinking water raises questions about the efficacy of some water treatment processes to remove viruses from polluted water.

  3. Mesoporous Silicon with Modified Surface for Plant Viruses and Their Protein Particle Sensing

    Directory of Open Access Journals (Sweden)

    Kae Dal Kwack

    2008-10-01

    Full Text Available Changes in electric parameters of a mesoporous silicon treated by a plasma chemical etching with fluorine and hydrogen ions, under the adsorption of NEPO (Nematodetransmitted Polyhedral plant viruses such as TORSV (Tomato Ringspot Virus, GFLV (Grapevine Fan Leaf Virus and protein macromolecule from TORSV particles are described. The current response to the applied voltage is measured for each virus particle to investigate the material parameters which are sensitive to the adsorbed particles. The peculiar behaviors of the response are modeled by the current-voltage relationship in a MOSFET. This model explains the behavior well and the double gate model of the MOSFET informs that the mesoporous silicon is a highly sensitive means of detecting the viruses in the size range less than 50 nm.

  4. The Arabidopsis synaptotagmin SYTA regulates the cell-to-cell movement of diverse plant viruses

    Directory of Open Access Journals (Sweden)

    Asako eUchiyama

    2014-11-01

    Full Text Available Synaptotagmins are a large gene family in animals that have been extensively characterized due to their role as calcium sensors to regulate synaptic vesicle exocytosis and endocytosis in neurons, and dense core vesicle exocytosis for hormone secretion from neuroendocrine cells. Thought to be exclusive to animals, synaptotagmins have recently been characterized in Arabidopsis thaliana, in which they comprise a five gene family. Using infectivity and leaf-based functional assays, we have shown that Arabidopsis SYTA regulates endocytosis and marks an endosomal vesicle recycling pathway to regulate movement protein-mediated trafficking of the Begomovirus Cabbage leaf curl virus (CaLCuV and the Tobamovirus Tobacco mosaic virus (TMV through plasmodesmata (Lewis and Lazarowitz, 2010. To determine whether SYTA has a central role in regulating the cell-to-cell trafficking of a wider range of diverse plant viruses, we extended our studies here to examine the role of SYTA in the cell-to-cell movement of additional plant viruses that employ different modes of movement, namely the Potyvirus Turnip mosaic virus (TuMV, the Caulimovirus Cauliflower mosaic virus (CaMV and the Tobamovirus Turnip vein clearing virus (TVCV, which in contrast to TMV does efficiently infect Arabidopsis. We found that both TuMV and TVCV systemic infection, and the cell-to-cell trafficking of the their movement proteins, were delayed in the Arabidopsis Col-0 syta-1 knockdown mutant. In contrast, CaMV systemic infection was not inhibited in syta-1. Our studies show that SYTA is a key regulator of plant virus intercellular movement, being necessary for the ability of diverse cell-to-cell movement proteins encoded by Begomoviruses (CaLCuV MP, Tobamoviruses (TVCV and TMV 30K protein and Potyviruses (TuMV P3N-PIPO to alter PD and thereby mediate virus cell-to-cell spread.

  5. Biotechnological approaches to determine the impact of viruses in the energy crop plant Jatropha curcas

    Science.gov (United States)

    2011-01-01

    Background Geminiviruses infect a wide range of plant species including Jatropha and cassava both belonging to family Euphorbiaceae. Cassava is traditionally an important food crop in Sub - Saharan countries, while Jatropha is considered as valuable biofuel plant with great perspectives in the future. Results A total of 127 Jatropha samples from Ethiopia and Kenya and 124 cassava samples from Kenya were tested by Enzyme-Linked Immunosorbent Assay (ELISA) for RNA viruses and polymerase chain reaction for geminiviruses. Jatropha samples from 4 different districts in Kenya and Ethiopia (analyzed by ELISA) were negative for all three RNA viruses tested: Cassava brown streak virus (CBSV), Cassava common mosaic virus, Cucumber mosaic virus, Three cassava samples from Busia district (Kenya) contained CBSV. Efforts to develop diagnostic approaches allowing reliable pathogen detection in Jatropha, involved the amplification and sequencing of the entire DNA A molecules of 40 Kenyan isolates belonging to African cassava mosaic virus (ACMV) and East African cassava mosaic virus - Uganda. This information enabled the design of novel primers to address different questions: a) primers amplifying longer sequences led to a phylogenetic tree of isolates, allowing some predictions on the evolutionary aspects of Begomoviruses in Jatrophia; b) primers amplifying shorter sequences represent a reliable diagnostic tool. This is the first report of the two Begomoviruses in J. curcas. Two cassava samples were co - infected with cassava mosaic geminivirus and CBSV. A Defective DNA A of ACMV was found for the first time in Jatropha. Conclusion Cassava geminiviruses occurring in Jatropha might be spread wider than anticipated. If not taken care of, this virus infection might negatively impact large scale plantations for biofuel production. Being hosts for similar pathogens, the planting vicinity of the two crop plants needs to be handled carefully. PMID:21812981

  6. Biotechnological approaches to determine the impact of viruses in the energy crop plant Jatropha curcas

    Directory of Open Access Journals (Sweden)

    Maghuly Fatemeh

    2011-08-01

    Full Text Available Abstract Background Geminiviruses infect a wide range of plant species including Jatropha and cassava both belonging to family Euphorbiaceae. Cassava is traditionally an important food crop in Sub - Saharan countries, while Jatropha is considered as valuable biofuel plant with great perspectives in the future. Results A total of 127 Jatropha samples from Ethiopia and Kenya and 124 cassava samples from Kenya were tested by Enzyme-Linked Immunosorbent Assay (ELISA for RNA viruses and polymerase chain reaction for geminiviruses. Jatropha samples from 4 different districts in Kenya and Ethiopia (analyzed by ELISA were negative for all three RNA viruses tested: Cassava brown streak virus (CBSV, Cassava common mosaic virus, Cucumber mosaic virus, Three cassava samples from Busia district (Kenya contained CBSV. Efforts to develop diagnostic approaches allowing reliable pathogen detection in Jatropha, involved the amplification and sequencing of the entire DNA A molecules of 40 Kenyan isolates belonging to African cassava mosaic virus (ACMV and East African cassava mosaic virus - Uganda. This information enabled the design of novel primers to address different questions: a primers amplifying longer sequences led to a phylogenetic tree of isolates, allowing some predictions on the evolutionary aspects of Begomoviruses in Jatrophia; b primers amplifying shorter sequences represent a reliable diagnostic tool. This is the first report of the two Begomoviruses in J. curcas. Two cassava samples were co - infected with cassava mosaic geminivirus and CBSV. A Defective DNA A of ACMV was found for the first time in Jatropha. Conclusion Cassava geminiviruses occurring in Jatropha might be spread wider than anticipated. If not taken care of, this virus infection might negatively impact large scale plantations for biofuel production. Being hosts for similar pathogens, the planting vicinity of the two crop plants needs to be handled carefully.

  7. Progress in Decommissioning the Humboldt Bay Power Plant - 13604

    Energy Technology Data Exchange (ETDEWEB)

    Rod, Kerry [PG and E Utility, Humboldt Bay Power Plant, 1000 King Salmon Ave. Eureka, CA 95503 (United States); Shelanskey, Steven K. [Anata Management Solutions, 5180 South Commerce Dr,, Suite F Murray, UT 84107 (United States); Kristofzski, John [CH2MHILL, 295 Bradley Blvd. Suite 300, Richland WA 99353 (United States)

    2013-07-01

    Decommissioning of the Pacific Gas and Electric (PG and E) Company Humboldt Bay Power Plant (HBPP) Unit 3 nuclear facility has now, after more than three decades of SAFSTOR and initial decommissioning work, transitioned to full-scale decommissioning. Decommissioning activities to date have been well orchestrated and executed in spite of an extremely small work site with space constricted even more by other concurrent on-site major construction projects including the demolition of four fossil units, construction of a new generating station and 60 KV switchyard upgrade. Full-scale decommissioning activities - now transitioning from Plant Systems Removal (PG and E self-perform) to Civil Works Projects (contractor performed) - are proceeding in a safe, timely, and cost effective manner. As a result of the successful decommissioning work to date (approximately fifty percent completed) and the intense planning and preparations for the remaining work, there is a high level of confidence for completion of all HBPP Unit 3 decommissions activities in 2018. Strategic planning and preparations to transition into full-scale decommissioning was carried out in 2008 by a small, highly focused project team. This planning was conducted concurrent with other critical planning requirements such as the loading of spent nuclear fuel into dry storage at the Independent Spent Fuel Storage Installation (ISFSI) finishing December 2008. Over the past four years, 2009 through 2012, the majority of decommissioning work has been installation of site infrastructure and removal of systems and components, known as the Plant System Removal Phase, where work scope was dynamic with significant uncertainty, and it was self-performed by PG and E. As HBPP Decommissioning transitions from the Plant System Removal Phase to the Civil Works Projects Phase, where work scope is well defined, a contracting plan similar to that used for Fossil Decommissioning will be implemented. Award of five major work scopes

  8. Progress in Decommissioning the Humboldt Bay Power Plant - 13604

    International Nuclear Information System (INIS)

    Rod, Kerry; Shelanskey, Steven K.; Kristofzski, John

    2013-01-01

    Decommissioning of the Pacific Gas and Electric (PG and E) Company Humboldt Bay Power Plant (HBPP) Unit 3 nuclear facility has now, after more than three decades of SAFSTOR and initial decommissioning work, transitioned to full-scale decommissioning. Decommissioning activities to date have been well orchestrated and executed in spite of an extremely small work site with space constricted even more by other concurrent on-site major construction projects including the demolition of four fossil units, construction of a new generating station and 60 KV switchyard upgrade. Full-scale decommissioning activities - now transitioning from Plant Systems Removal (PG and E self-perform) to Civil Works Projects (contractor performed) - are proceeding in a safe, timely, and cost effective manner. As a result of the successful decommissioning work to date (approximately fifty percent completed) and the intense planning and preparations for the remaining work, there is a high level of confidence for completion of all HBPP Unit 3 decommissions activities in 2018. Strategic planning and preparations to transition into full-scale decommissioning was carried out in 2008 by a small, highly focused project team. This planning was conducted concurrent with other critical planning requirements such as the loading of spent nuclear fuel into dry storage at the Independent Spent Fuel Storage Installation (ISFSI) finishing December 2008. Over the past four years, 2009 through 2012, the majority of decommissioning work has been installation of site infrastructure and removal of systems and components, known as the Plant System Removal Phase, where work scope was dynamic with significant uncertainty, and it was self-performed by PG and E. As HBPP Decommissioning transitions from the Plant System Removal Phase to the Civil Works Projects Phase, where work scope is well defined, a contracting plan similar to that used for Fossil Decommissioning will be implemented. Award of five major work scopes

  9. Restriction of virus infection by plants. Final report, July 1, 1987--June 30, 1992

    Energy Technology Data Exchange (ETDEWEB)

    Bruening, G.

    1992-12-31

    The basis of genotypic resistance of the Arlington line of cowpea (Vigna unguiculata) against cowpea mosaic virus (CPMV) has been attributed, to an inhibitor of the processing of CPMV polyproteins. We sought to purify the protein that is postulated to be the inhibitor of polyprotein processing and to characterize the inhibitor and its gene. Such information can be the basis for engineering resistance to specific viruses in plants. In studies with cherry leafroll virus (CLRV) we sought understanding of the biochemical basis of the resistance.

  10. Role of Pea Enation Mosaic Virus Coat Protein in the Host Plant and Aphid Vector.

    Science.gov (United States)

    Doumayrou, Juliette; Sheber, Melissa; Bonning, Bryony C; Miller, W Allen

    2016-11-18

    Understanding the molecular mechanisms involved in plant virus-vector interactions is essential for the development of effective control measures for aphid-vectored epidemic plant diseases. The coat proteins (CP) are the main component of the viral capsids, and they are implicated in practically every stage of the viral infection cycle. Pea enation mosaic virus 1 (PEMV1, Enamovirus , Luteoviridae ) and Pea enation mosaic virus 2 (PEMV2, Umbravirus , Tombusviridae ) are two RNA viruses in an obligate symbiosis causing the pea enation mosaic disease. Sixteen mutant viruses were generated with mutations in different domains of the CP to evaluate the role of specific amino acids in viral replication, virion assembly, long-distance movement in Pisum sativum , and aphid transmission. Twelve mutant viruses were unable to assemble but were able to replicate in inoculated leaves, move long-distance, and express the CP in newly infected leaves. Four mutant viruses produced virions, but three were not transmissible by the pea aphid, Acyrthosiphon pisum . Three-dimensional modeling of the PEMV CP, combined with biological assays for virion assembly and aphid transmission, allowed for a model of the assembly of PEMV coat protein subunits.

  11. Autophagy pathway induced by a plant virus facilitates viral spread and transmission by its insect vector.

    Directory of Open Access Journals (Sweden)

    Yong Chen

    2017-11-01

    Full Text Available Many viral pathogens are persistently transmitted by insect vectors and cause agricultural or health problems. Generally, an insect vector can use autophagy as an intrinsic antiviral defense mechanism against viral infection. Whether viruses can evolve to exploit autophagy to promote their transmission by insect vectors is still unknown. Here, we show that the autophagic process is triggered by the persistent replication of a plant reovirus, rice gall dwarf virus (RGDV in cultured leafhopper vector cells and in intact insects, as demonstrated by the appearance of obvious virus-containing double-membrane autophagosomes, conversion of ATG8-I to ATG8-II and increased level of autophagic flux. Such virus-containing autophagosomes seem able to mediate nonlytic viral release from cultured cells or facilitate viral spread in the leafhopper intestine. Applying the autophagy inhibitor 3-methyladenine or silencing the expression of Atg5 significantly decrease viral spread in vitro and in vivo, whereas applying the autophagy inducer rapamycin or silencing the expression of Torc1 facilitate such viral spread. Furthermore, we find that activation of autophagy facilitates efficient viral transmission, whereas inhibiting autophagy blocks viral transmission by its insect vector. Together, these results indicate a plant virus can induce the formation of autophagosomes for carrying virions, thus facilitating viral spread and transmission by its insect vector. We believe that such a role for virus-induced autophagy is common for vector-borne persistent viruses during their transmission by insect vectors.

  12. Plant Virus Infection and the Ubiquitin Proteasome Machinery: Arms Race along the Endoplasmic Reticulum.

    Science.gov (United States)

    Verchot, Jeanmarie

    2016-11-19

    The endoplasmic reticulum (ER) is central to plant virus replication, translation, maturation, and egress. Ubiquitin modification of ER associated cellular and viral proteins, alongside the actions of the 26S proteasome, are vital for the regulation of infection. Viruses can arrogate ER associated ubiquitination as well as cytosolic ubiquitin ligases with the purpose of directing the ubiquitin proteasome system (UPS) to new targets. Such targets include necessary modification of viral proteins which may stabilize certain complexes, or modification of Argonaute to suppress gene silencing. The UPS machinery also contributes to the regulation of effector triggered immunity pattern recognition receptor immunity. Combining the results of unrelated studies, many positive strand RNA plant viruses appear to interact with cytosolic Ub-ligases to provide novel avenues for controlling the deleterious consequences of disease. Viral interactions with the UPS serve to regulate virus infection in a manner that promotes replication and movement, but also modulates the levels of RNA accumulation to ensure successful biotrophic interactions. In other instances, the UPS plays a central role in cellular immunity. These opposing roles are made evident by contrasting studies where knockout mutations in the UPS can either hamper viruses or lead to more aggressive diseases. Understanding how viruses manipulate ER associated post-translational machineries to better manage virus-host interactions will provide new targets for crop improvement.

  13. Coilin, the signature protein of Cajal bodies, differentially modulates the interactions of plants with viruses in widely different taxa.

    Science.gov (United States)

    Shaw, Jane; Love, Andrew J; Makarova, Svetlana S; Kalinina, Natalia O; Harrison, Bryan D; Taliansky, Michael E

    2014-01-01

    Cajal bodies (CBs) are distinct nuclear bodies physically and functionally associated with the nucleolus. In addition to their traditional function in coordinating maturation of certain nuclear RNAs, CBs participate in cell cycle regulation, development, and regulation of stress responses. A key "signature" component of CBs is coilin, the scaffolding protein essential for CB formation and function. Using an RNA silencing (loss-of-function) approach, we describe here new phenomena whereby coilin also affects, directly or indirectly, a variety of interactions between host plants and viruses that have RNA or DNA genomes. Moreover, the effects of coilin on these interactions are manifested differently: coilin contributes to plant defense against tobacco rattle virus (tobravirus), tomato black ring virus (nepovirus), barley stripe mosaic virus (hordeivirus), and tomato golden mosaic virus (begomovirus). In contrast, with potato virus Y (potyvirus) and turnip vein clearing virus (tobamovirus), coilin serves to increase virus pathogenicity. These findings show that interactions with coilin (or CBs) may involve diverse mechanisms with different viruses and that these mechanisms act at different phases of virus infection. Thus, coilin (CBs) has novel, unexpected natural functions that may be recruited or subverted by plant viruses for their own needs or, in contrast, are involved in plant defense mechanisms that suppress host susceptibility to the viruses.

  14. Rapid immunohistochemical diagnosis of tobacco mosaic virus disease by microwave-assisted plant sample preparation

    Science.gov (United States)

    Zellnig, Günther; Möstl, Stefan; Zechmann, Bernd

    2013-01-01

    Immunoelectron microscopy is a powerful method to diagnose viral diseases and to study the distribution of the viral agent within plant cells and tissues. Nevertheless, current protocols for the immunological detection of viral diseases with transmission electron microscopy (TEM) in plants take between 3 and 6 days and are therefore not suited for rapid diagnosis of virus diseases in plants. In this study, we describe a method that allows rapid cytohistochemical detection of tobacco mosaic virus (TMV) in leaves of tobacco plants. With the help of microwave irradiation, sample preparation of the leaves was reduced to 90 min. After sample sectioning, virus particles were stained on the sections by immunogold labelling of the viral coat protein, which took 100 min. After investigation with the TEM, a clear visualization of TMV in tobacco cells was achieved altogether in about half a day. Comparison of gold particle density by image analysis revealed that samples prepared with the help of microwave irradiation yielded significantly higher gold particle density as samples prepared conventionally at room temperature. This study clearly demonstrates that microwave-assisted plant sample preparation in combination with cytohistochemical localization of viral coat protein is well suited for rapid diagnosis of plant virus diseases in altogether about half a day by TEM. PMID:23580761

  15. Geometagenomics illuminates the impact of agriculture on the distribution and prevalence of plant viruses at the ecosystem scale.

    Science.gov (United States)

    Bernardo, Pauline; Charles-Dominique, Tristan; Barakat, Mohamed; Ortet, Philippe; Fernandez, Emmanuel; Filloux, Denis; Hartnady, Penelope; Rebelo, Tony A; Cousins, Stephen R; Mesleard, François; Cohez, Damien; Yavercovski, Nicole; Varsani, Arvind; Harkins, Gordon W; Peterschmitt, Michel; Malmstrom, Carolyn M; Martin, Darren P; Roumagnac, Philippe

    2018-01-01

    Disease emergence events regularly result from human activities such as agriculture, which frequently brings large populations of genetically uniform hosts into contact with potential pathogens. Although viruses cause nearly 50% of emerging plant diseases, there is little systematic information about virus distribution across agro-ecological interfaces and large gaps in understanding of virus diversity in nature. Here we applied a novel landscape-scale geometagenomics approach to examine relationships between agricultural land use and distributions of plant-associated viruses in two Mediterranean-climate biodiversity hotspots (Western Cape region of South Africa and Rhône river delta region of France). In total, we analysed 1725 geo-referenced plant samples collected over two years from 4.5 × 4.5 km 2 grids spanning farmlands and adjacent uncultivated vegetation. We found substantial virus prevalence (25.8-35.7%) in all ecosystems, but prevalence and identified family-level virus diversity were greatest in cultivated areas, with some virus families displaying strong agricultural associations. Our survey revealed 94 previously unknown virus species, primarily from uncultivated plants. This is the first effort to systematically evaluate plant-associated viromes across broad agro-ecological interfaces. Our findings indicate that agriculture substantially influences plant virus distributions and highlight the extent of current ignorance about the diversity and roles of viruses in nature.

  16. Low Temperature Storage of Southern Rice Black-Streaked Dwarf Virus-Infected Rice Plants Cannot Sustain Virus Transmission by the Vector.

    Science.gov (United States)

    Liu, Danfeng; Li, Pei; Han, Yongqiang; Lei, Wenbin; Hou, Maolin

    2016-02-01

    Southern rice black-streaked dwarf virus (SRBSDV) is a novel virus transmitted by white-backed planthopper Sogatella furcifera (Hováth) (Hemiptera: Delphacidae). Due to low virus transmission efficiency by the planthopper, researchers are frequently confronted with shortage of viruliferous vectors or infected rice plants, especially in winter and the following spring. To find new ways to maintain virus-infected materials, viral rice plants were stored at -80°C for 45 or 140 d and evaluated as virus sources in virus transmission by the vector. SRBSDV virions were not degraded during storage at -80°C as indicated by reverse transcription-polymerase chain reaction and reverse transcription real-time PCR detection. The planthopper nymphs fed on the infected thawed plants for 48 h survived at about 40% and showed positive detection of SRBSDV, but they lost the virus after feeding for another 20 d (the circulative transmission period) on noninfected plants. Transmission electron microscope images indicated broken capsid of virions in infected thawed leaves in contrast to integrity capsid of virions in infected fresh leaves. These results show that low temperature storage of SRBSDV-infected rice plants cannot sustain virus transmission by white-backed planthopper. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  17. The first phlebo-like virus infecting plants: a case study on the adaptation of negative-stranded RNA viruses to new hosts.

    Science.gov (United States)

    Navarro, Beatriz; Minutolo, Maria; De Stradis, Angelo; Palmisano, Francesco; Alioto, Daniela; Di Serio, Francesco

    2018-05-01

    A novel negative-stranded (ns) RNA virus associated with a severe citrus disease reported more than 80 years ago has been identified. Transmission electron microscopy showed that this novel virus, tentatively named citrus concave gum-associated virus, is flexuous and non-enveloped. Notwithstanding, its two genomic RNAs share structural features with members of the genus Phlebovirus, which are enveloped arthropod-transmitted viruses infecting mammals, and with a group of still unclassified phlebo-like viruses mainly infecting arthropods. CCGaV genomic RNAs code for an RNA-dependent RNA polymerase, a nucleocapsid protein and a putative movement protein showing structural and phylogenetic relationships with phlebo-like viruses, phleboviruses and the unrelated ophioviruses, respectively, thus providing intriguing evidence of a modular genome evolution. Phylogenetic reconstructions identified an invertebrate-restricted virus as the most likely ancestor of this virus, revealing that its adaptation to plants was independent from and possibly predated that of the other nsRNA plant viruses. These data are consistent with an evolutionary scenario in which trans-kingdom adaptation occurred several times during the history of nsRNA viruses and followed different evolutionary pathways, in which genomic RNA segments were gained or lost. The need to create a new genus for this bipartite nsRNA virus and the impact of the rapid and specific detection methods developed here on citrus sanitation and certification are also discussed. © 2017 BSPP AND JOHN WILEY & SONS LTD.

  18. Recent progress in plant nutrition research: cross-talk between nutrients, plant physiology and soil microorganisms.

    Science.gov (United States)

    Ohkama-Ohtsu, Naoko; Wasaki, Jun

    2010-08-01

    Mineral nutrients taken up from the soil become incorporated into a variety of important compounds with structural and physiological roles in plants. We summarize how plant nutrients are linked to many metabolic pathways, plant hormones and other biological processes. We also focus on nutrient uptake, describing plant-microbe interactions, plant exudates, root architecture, transporters and their applications. Plants need to survive in soils with mineral concentrations that vary widely. Describing the relationships between nutrients and biological processes will enable us to understand the molecular basis for signaling, physiological damage and responses to mineral stresses.

  19. Vertically acquired hepatitis C virus infection: Correlates of transmission and disease progression.

    Science.gov (United States)

    Tovo, Pier-Angelo; Calitri, Carmelina; Scolfaro, Carlo; Gabiano, Clara; Garazzino, Silvia

    2016-01-28

    The worldwide prevalence of hepatitis C virus (HCV) infection in children is 0.05%-0.4% in developed countries and 2%-5% in resource-limited settings, where inadequately tested blood products or un-sterile medical injections still remain important routes of infection. After the screening of blood donors, mother-to-child transmission (MTCT) of HCV has become the leading cause of pediatric infection, at a rate of 5%. Maternal HIV co-infection is a significant risk factor for MTCT and anti-HIV therapy during pregnancy seemingly can reduce the transmission rate of both viruses. Conversely, a high maternal viral load is an important, but not preventable risk factor, because at present no anti-HCV treatment can be administered to pregnant women to block viral replication. Caution is needed in adopting obstetric procedures, such as amniocentesis or internal fetal monitoring, that can favor fetal exposure to HCV contaminated maternal blood, though evidence is lacking on the real risk of single obstetric practices. Mode of delivery and type of feeding do not represent significant risk factors for MTCT. Therefore, there is no reason to offer elective caesarean section or discourage breast-feeding to HCV infected parturients. Information on the natural history of vertical HCV infection is limited. The primary infection is asymptomatic in infants. At least one quarter of infected children shows a spontaneous viral clearance (SVC) that usually occurs within 6 years of life. IL-28B polymorphims and genotype 3 infection have been associated with greater chances of SVC. In general, HCV progression is mild or moderate in children with chronic infection who grow regularly, though cases with marked liver fibrosis or hepatic failure have been described. Non-organ specific autoantibodies and cryoglobulins are frequently found in children with chronic infection, but autoimmune diseases or HCV associated extrahepatic manifestations are rare.

  20. First discovery of acetone extract from cottonseed oil sludge as a novel antiviral agent against plant viruses.

    Science.gov (United States)

    Zhao, Lei; Feng, Chaohong; Hou, Caiting; Hu, Lingyun; Wang, Qiaochun; Wu, Yunfeng

    2015-01-01

    A novel acetone extract from cottonseed oil sludge was firstly discovered against plant viruses including Tobacco mosaic virus (TMV), Rice stripe virus (RSV) and Southern rice black streaked dwarf virus (SRBSDV). Gossypol and β-sitosterol separated from the acetone extract were tested for their effects on anti-TMV and analysed by nuclear magnetic resonance (NMR) assay. In vivo and field trials in different geographic distributions and different host varieties declared that this extract mixture was more efficient than the commercial agent Ningnanmycin with a broad spectrum of anti-plant-viruses activity. No phytotoxic activity was observed in the treated plants and environmental toxicology showed that this new acetone extract was environmentally friendly, indicating that this acetone extract has potential application in the control of plant virus in the future.

  1. 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.

  2. Recent Progress on Data-Based Optimization for Mineral Processing Plants

    Directory of Open Access Journals (Sweden)

    Jinliang Ding

    2017-04-01

    Full Text Available In the globalized market environment, increasingly significant economic and environmental factors within complex industrial plants impose importance on the optimization of global production indices; such optimization includes improvements in production efficiency, product quality, and yield, along with reductions of energy and resource usage. This paper briefly overviews recent progress in data-driven hybrid intelligence optimization methods and technologies in improving the performance of global production indices in mineral processing. First, we provide the problem description. Next, we summarize recent progress in data-based optimization for mineral processing plants. This optimization consists of four layers: optimization of the target values for monthly global production indices, optimization of the target values for daily global production indices, optimization of the target values for operational indices, and automation systems for unit processes. We briefly overview recent progress in each of the different layers. Finally, we point out opportunities for future works in data-based optimization for mineral processing plants.

  3. Phosphatidic acid produced by phospholipase D promotes RNA replication of a plant RNA virus.

    Directory of Open Access Journals (Sweden)

    Kiwamu Hyodo

    2015-05-01

    Full Text Available Eukaryotic positive-strand RNA [(+RNA] viruses are intracellular obligate parasites replicate using the membrane-bound replicase complexes that contain multiple viral and host components. To replicate, (+RNA viruses exploit host resources and modify host metabolism and membrane organization. Phospholipase D (PLD is a phosphatidylcholine- and phosphatidylethanolamine-hydrolyzing enzyme that catalyzes the production of phosphatidic acid (PA, a lipid second messenger that modulates diverse intracellular signaling in various organisms. PA is normally present in small amounts (less than 1% of total phospholipids, but rapidly and transiently accumulates in lipid bilayers in response to different environmental cues such as biotic and abiotic stresses in plants. However, the precise functions of PLD and PA remain unknown. Here, we report the roles of PLD and PA in genomic RNA replication of a plant (+RNA virus, Red clover necrotic mosaic virus (RCNMV. We found that RCNMV RNA replication complexes formed in Nicotiana benthamiana contained PLDα and PLDβ. Gene-silencing and pharmacological inhibition approaches showed that PLDs and PLDs-derived PA are required for viral RNA replication. Consistent with this, exogenous application of PA enhanced viral RNA replication in plant cells and plant-derived cell-free extracts. We also found that a viral auxiliary replication protein bound to PA in vitro, and that the amount of PA increased in RCNMV-infected plant leaves. Together, our findings suggest that RCNMV hijacks host PA-producing enzymes to replicate.

  4. Inactivated recombinant plant virus protects dogs from a lethal challenge with canine parvovirus.

    Science.gov (United States)

    Langeveld, J P; Brennan, F R; Martínez-Torrecuadrada, J L; Jones, T D; Boshuizen, R S; Vela, C; Casal, J I; Kamstrup, S; Dalsgaard, K; Meloen, R H; Bendig, M M; Hamilton, W D

    2001-06-14

    A vaccine based upon a recombinant plant virus (CPMV-PARVO1), displaying a peptide derived from the VP2 capsid protein of canine parvovirus (CPV), has previously been described. To date, studies with the vaccine have utilized viable plant chimaeric particles (CVPs). In this study, CPMV-PARVO1 was inactivated by UV treatment to remove the possibility of replication of the recombinant plant virus in a plant host after manufacture of the vaccine. We show that the inactivated CVP is able to protect dogs from a lethal challenge with CPV following parenteral immunization with the vaccine. Dogs immunized with the inactivated CPMV-PARVO1 in adjuvant displayed no clinical signs of disease and shedding of CPV in faeces was limited following CPV challenge. All immunized dogs elicited high titres of peptide-specific antibody, which neutralized CPV in vitro. Levels of protection, virus shedding and VP2-specific antibody were comparable to those seen in dogs immunized with the same VP2- peptide coupled to keyhole limpet hemocyanin (KLH). Since plant virus-derived vaccines have the potential for cost-effective manufacture and are not known to replicate in mammalian cells, they represent a viable alternative to current replicating vaccine vectors for development of both human and veterinary vaccines.

  5. Role of Pea Enation Mosaic Virus Coat Protein in the Host Plant and Aphid Vector

    Directory of Open Access Journals (Sweden)

    Juliette Doumayrou

    2016-11-01

    Full Text Available Understanding the molecular mechanisms involved in plant virus–vector interactions is essential for the development of effective control measures for aphid-vectored epidemic plant diseases. The coat proteins (CP are the main component of the viral capsids, and they are implicated in practically every stage of the viral infection cycle. Pea enation mosaic virus 1 (PEMV1, Enamovirus, Luteoviridae and Pea enation mosaic virus 2 (PEMV2, Umbravirus, Tombusviridae are two RNA viruses in an obligate symbiosis causing the pea enation mosaic disease. Sixteen mutant viruses were generated with mutations in different domains of the CP to evaluate the role of specific amino acids in viral replication, virion assembly, long-distance movement in Pisum sativum, and aphid transmission. Twelve mutant viruses were unable to assemble but were able to replicate in inoculated leaves, move long-distance, and express the CP in newly infected leaves. Four mutant viruses produced virions, but three were not transmissible by the pea aphid, Acyrthosiphon pisum. Three-dimensional modeling of the PEMV CP, combined with biological assays for virion assembly and aphid transmission, allowed for a model of the assembly of PEMV coat protein subunits.

  6. Plant Virus Infection and the Ubiquitin Proteasome Machinery: Arms Race along the Endoplasmic Reticulum

    Directory of Open Access Journals (Sweden)

    Jeanmarie Verchot

    2016-11-01

    Full Text Available The endoplasmic reticulum (ER is central to plant virus replication, translation, maturation, and egress. Ubiquitin modification of ER associated cellular and viral proteins, alongside the actions of the 26S proteasome, are vital for the regulation of infection. Viruses can arrogate ER associated ubiquitination as well as cytosolic ubiquitin ligases with the purpose of directing the ubiquitin proteasome system (UPS to new targets. Such targets include necessary modification of viral proteins which may stabilize certain complexes, or modification of Argonaute to suppress gene silencing. The UPS machinery also contributes to the regulation of effector triggered immunity pattern recognition receptor immunity. Combining the results of unrelated studies, many positive strand RNA plant viruses appear to interact with cytosolic Ub-ligases to provide novel avenues for controlling the deleterious consequences of disease. Viral interactions with the UPS serve to regulate virus infection in a manner that promotes replication and movement, but also modulates the levels of RNA accumulation to ensure successful biotrophic interactions. In other instances, the UPS plays a central role in cellular immunity. These opposing roles are made evident by contrasting studies where knockout mutations in the UPS can either hamper viruses or lead to more aggressive diseases. Understanding how viruses manipulate ER associated post-translational machineries to better manage virus–host interactions will provide new targets for crop improvement.

  7. Temporal Progression of Lesions in Guinea Pigs Infected With Lassa Virus.

    Science.gov (United States)

    Bell, T M; Shaia, C I; Bearss, J J; Mattix, M E; Koistinen, K A; Honnold, S P; Zeng, X; Blancett, C D; Donnelly, G C; Shamblin, J D; Wilkinson, E R; Cashman, K A

    2017-05-01

    Lassa virus (LASV) infection causes an acute, multisystemic viral hemorrhagic fever that annually infects an estimated 100 000 to 300 000 persons in West Africa. This pathogenesis study evaluated the temporal progression of disease in guinea pigs following aerosol and subcutaneous inoculation of the Josiah strain of LASV as well as the usefulness of Strain 13 guinea pigs as an animal model for Lassa fever. After experimental infection, guinea pigs ( Cavia porcellus; n = 67) were serially sampled to evaluate the temporal progression of infection, gross and histologic lesions, and serum chemistry and hematologic changes. Guinea pigs developed viremia on day 5 to 6 postexposure (PE), with clinical signs appearing by day 7 to 8 PE. Complete blood counts revealed lymphopenia and thrombocytopenia. Gross pathologic findings included skin lesions and congested lungs. Histologic lesions consisted of cortical lymphoid depletion by day 6 to 7 PE with lymphohistiocytic interstitial pneumonia at 7 to 8 days PE. Scattered hepatocellular degeneration and cell death were also noted in the liver and, to a lesser extent, in other tissues including the haired skin, lung, heart, adrenal gland, lymph nodes, thymus, and spleen. The first cell types to demonstrate staining for viral antigen were fibroblastic reticular cells and macrophages/dendritic cells in the lymph nodes on day 5 to 6 PE. This study demonstrates similarities between Lassa viral disease in human infections and experimental guinea pig infection. These shared pathologic characteristics support the utility of guinea pigs as an additional animal model for vaccine and therapeutic development under the Food and Drug Administration's Animal Rule.

  8. Plant-feeding insects harbor double-stranded RNA viruses encoding a novel proline-alanine rich protein and a polymerase distantly related to that of fungal viruses

    Science.gov (United States)

    Novel double-stranded RNAs (~8 kbp) were isolated from three cornered alfalfa hopper (Spissistilus festinus) and beet leafhopper (Circulifer tenellus), two plant-feeding hemipteran insect pests. Genomes of the two new viruses, designated as Spissistilus festinus virus 1 (SpFV1) and Circulifer tenell...

  9. Novel double-stranded RNA viruses of plant-feeding insects encode a serine-alanine-proline rich protein and a polymerase distantly related to fungal viruses

    Science.gov (United States)

    Novel double stranded RNAs (~8 kbp) were isolated from the three cornered alfalfa hopper (Spissistilus festinus) and beet leafhopper (Circulifer tenellus), two plant-feeding hemipteran insect pests. Genome organization of the two new viruses, designated as Spissistilus festinus virus 1 (SpFV1) and ...

  10. RNA Interference in Insect Vectors for Plant Viruses

    OpenAIRE

    Kanakala, Surapathrudu; Ghanim, Murad

    2016-01-01

    Insects and other arthropods are the most important vectors of plant pathogens. The majority of plant pathogens are disseminated by arthropod vectors such as aphids, beetles, leafhoppers, planthoppers, thrips and whiteflies. Transmission of plant pathogens and the challenges in managing insect vectors due to insecticide resistance are factors that contribute to major food losses in agriculture. RNA interference (RNAi) was recently suggested as a promising strategy for controlling insect pests...

  11. 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

  12. 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

  13. Host genetic risk factors for West Nile virus infection and disease progression.

    Directory of Open Access Journals (Sweden)

    Abigail W Bigham

    Full Text Available West Nile virus (WNV, a category B pathogen endemic in parts of Africa, Asia and Europe, emerged in North America in 1999, and spread rapidly across the continental U.S. Outcomes of infection with WNV range from asymptomatic to severe neuroinvasive disease manifested as encephalitis, paralysis, and/or death. Neuroinvasive WNV disease occurs in less than one percent of cases, and although host genetic factors are thought to influence risk for symptomatic disease, the identity of these factors remains largely unknown. We tested 360 common haplotype tagging and/or functional SNPs in 86 genes that encode key regulators of immune function in 753 individuals infected with WNV including: 422 symptomatic WNV cases and 331 cases with asymptomatic infections. After applying a Bonferroni correction for multiple tests and controlling for population stratification, SNPs in IRF3 (OR 0.54, p = 0.035 and MX1, (OR 0.19, p = 0.014 were associated with symptomatic WNV infection and a single SNP in OAS1 (OR 9.79, p = 0.003 was associated with increased risk for West Nile encephalitis and paralysis (WNE/P. Together, these results suggest that genetic variation in the interferon response pathway is associated with both risk for symptomatic WNV infection and WNV disease progression.

  14. Imbalance of tumor necrosis factor receptors during progression in bovine leukemia virus infection

    International Nuclear Information System (INIS)

    Konnai, Satoru; Usui, Tatsufumi; Ikeda, Manabu; Kohara, Junko; Hirata, Toh-ichi; Okada, Kosuke; Ohashi, Kazuhiko; Onuma, Misao

    2005-01-01

    Previously, we found an up-regulation of tumor necrosis factor alpha (TNF)-α and an imbalance of TNF receptors in sheep experimentally infected with bovine leukemia virus (BLV). In order to investigate the different TNF-α-induced responses, in this study we examined the TNF-α-induced proliferative response and the expression levels of two distinct TNF receptors on peripheral blood mononuclear cells (PBMC) derived from BLV-uninfected cattle and BLV-infected cattle that were aleukemic (AL) or had persistent lymphocytosis (PL). The proliferative response of PBMC isolated from those cattle with PL in the presence of recombinant bovine TNF-α (rTNF-α) was significantly higher than those from AL cattle and uninfected cattle and the cells from PL cattle expressed significantly higher mRNA levels of TNF receptor type II (TNF-RII) than those from AL and BLV-uninfected cattle. No difference was found in TNF-RI mRNA levels. Most cells expressing TNF-RII in PL cattle were CD5 + or sIgM + cells and these cells showed resistance to TNF-α-induced apoptosis. Additionally, there were significant positive correlations between the changes in provirus load and TNF-RII mRNA levels, and TNF-α-induced proliferation and TNF-RII mRNA levels. These data suggest that imbalance in the expression of TNF receptors could at least in part contribute to the progression of lymphocytosis in BLV infection

  15. 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.

  16. The Impact of "Coat Protein-Mediated Virus Resistance" in Applied Plant Pathology and Basic Research.

    Science.gov (United States)

    Lindbo, John A; Falk, Bryce W

    2017-06-01

    Worldwide, plant viruses cause serious reductions in marketable crop yield and in some cases even plant death. In most cases, the most effective way to control virus diseases is through genetically controlled resistance. However, developing virus-resistant (VR) crops through traditional breeding can take many years, and in some cases is not even possible. Because of this, the demonstration of the first VR transgenic plants in 1985 generated much attention. This seminal report served as an inflection point for research in both basic and applied plant pathology, the results of which have dramatically changed both basic research and in a few cases, commercial crop production. The typical review article on this topic has focused on only basic or only applied research results stemming from this seminal discovery. This can make it difficult for the reader to appreciate the full impact of research on transgenic virus resistance, and the contributions from fundamental research that led to translational applications of this technology. In this review, we take a global view of this topic highlighting the significant changes to both basic and applied plant pathology research and commercial food production that have accumulated in the last 30 plus years. We present these milestones in the historical context of some of the scientific, economic, and environmental drivers for developing specific VR crops. The intent of this review is to provide a single document that adequately records the significant accomplishments of researchers in both basic and applied plant pathology research on this topic and how they relate to each other. We hope this review therefore serves as both an instructional tool for students new to the topic, as well as a source of conversation and discussion for how the technology of engineered virus resistance could be applied in the future.

  17. An efficient plant viral expression system generating orally immunogenic Norwalk virus-like particles.

    Science.gov (United States)

    Santi, Luca; Batchelor, Lance; Huang, Zhong; Hjelm, Brooke; Kilbourne, Jacquelyn; Arntzen, Charles J; Chen, Qiang; Mason, Hugh S

    2008-03-28

    Virus-like particles (VLPs) derived from enteric pathogens like Norwalk virus (NV) are well suited to study oral immunization. We previously described stable transgenic plants that accumulate recombinant NV-like particles (rNVs) that were orally immunogenic in mice and humans. The transgenic approach suffers from long generation time and modest level of antigen accumulation. We now overcome these constraints with an efficient tobacco mosaic virus (TMV)-derived transient expression system using leaves of Nicotiana benthamiana. We produced properly assembled rNV at 0.8 mg/g leaf 12 days post-infection (dpi). Oral immunization of CD1 mice with 100 or 250 microg/dose of partially purified rNV elicited systemic and mucosal immune responses. We conclude that the plant viral transient expression system provides a robust research tool to generate abundant quantities of rNV as enriched, concentrated VLP preparations that are orally immunogenic.

  18. First report of zucchini tigre mosaic virus infecting several cucurbit plants in China

    Science.gov (United States)

    Pumpkin (Cucurbita moschata Duch.), Cucumber (Cucumis sativus Linn.) and Zucchini (Cucurbita pepo Linn.) are important crops in tropical and subtropical regions in the world, and they are popular vegetable crops in China. There are currently 59 viruses known infecting cucurbit plants which including...

  19. Hybridization of plant virus ssRNAs Transferred to Hybond N membrane

    International Nuclear Information System (INIS)

    Kudela, O.; Kudelova, K.; Plaschke-Jakubik, K.

    1998-01-01

    In this paper we present a protocol for the non-denaturating agarose gel electrophoresis of plant virus ssRNAs, their blotting onto Hybond N membrane, and hybridization with [alpha 32 P]dNTP-labelled cDNA probe. The protocol is not pretentious on technical equipment, omits denaturation and neutralization steps and some chemical required in other modifications. (authors)

  20. Combined DECS Analysis and Next-Generation Sequencing Enable Efficient Detection of Novel Plant RNA Viruses

    Directory of Open Access Journals (Sweden)

    Hironobu Yanagisawa

    2016-03-01

    Full Text Available The presence of high molecular weight double-stranded RNA (dsRNA within plant cells is an indicator of infection with RNA viruses as these possess genomic or replicative dsRNA. DECS (dsRNA isolation, exhaustive amplification, cloning, and sequencing analysis has been shown to be capable of detecting unknown viruses. We postulated that a combination of DECS analysis and next-generation sequencing (NGS would improve detection efficiency and usability of the technique. Here, we describe a model case in which we efficiently detected the presumed genome sequence of Blueberry shoestring virus (BSSV, a member of the genus Sobemovirus, which has not so far been reported. dsRNAs were isolated from BSSV-infected blueberry plants using the dsRNA-binding protein, reverse-transcribed, amplified, and sequenced using NGS. A contig of 4,020 nucleotides (nt that shared similarities with sequences from other Sobemovirus species was obtained as a candidate of the BSSV genomic sequence. Reverse transcription (RT-PCR primer sets based on sequences from this contig enabled the detection of BSSV in all BSSV-infected plants tested but not in healthy controls. A recombinant protein encoded by the putative coat protein gene was bound by the BSSV-antibody, indicating that the candidate sequence was that of BSSV itself. Our results suggest that a combination of DECS analysis and NGS, designated here as “DECS-C,” is a powerful method for detecting novel plant viruses.

  1. Localization of potato leafroll virus in leaves of secondarily-infected potato plants

    NARCIS (Netherlands)

    Heuvel, van den J.F.J.M.; Blank, de C.M.; Peters, D.; Lent, van J.W.M.

    1995-01-01

    Potato leafroll virus (PLRV) antigen was localized by immunogold labelling in semi-thin leaf sections of secondarily-infected potato plants cv. Bintje. Viral antigen was present in all cell types of the phloem tissue. but occurred most abundantly in the companion cells. Detectable amounts of PLRV

  2. Characterization of viruses associated with garlic plants propagated from different reproductive tissues from Italy and other geographic regions

    Directory of Open Access Journals (Sweden)

    Leonardo PARRANO

    2013-01-01

    Full Text Available Garlic is an important crop cultivated worldwide and several different viruses have been associated with propagative material. Garlic is propagated from bulbs and/or from vegetative topsets of the inflorescences known as bulbils. The effects of the geographic origin and the type of the propagative material on the phylogenetic relationships and genetic variability of the coat protein genes of four allium viruses are presented here. Onion yellow dwarf virus (OYDV, Leek yellow stripe virus (LYSV, Garlic virus X (GVX, and Garlic common latent virus (GCLV were detected in single and mixed infections in plants grown either from bulbils and/or bulbs originating from Italy, China, Argentina, and the U.S.A. OYDV and LYSV fell into five and three well supported clades respectively whereas isolates of GVX and GCLV all clustered into one well-supported clade each. Some of the OYDV and LYSV clades presented evidence of host tissue selection while some phylogenetic structuring based on the geographic origin or host was also observed for some virus clades. Unique haplotypes and novel coat protein amino acid sequence patterns were identified for all viruses. An OYDV coat protein amino acid signature unique to Chenopodium quinoa, an uncommon host of the virus, was of particular interest. The type of propagative material affected the population dynamics of all of the viruses. The virus populations in plants propagated from bulbs were more diverse than in plants propagated from bulbils.

  3. A broad-spectrum, efficient and nontransgenic approach to control plant viruses by application of salicylic acid and jasmonic acid.

    Science.gov (United States)

    Shang, Jing; Xi, De-Hui; Xu, Fei; Wang, Shao-Dong; Cao, Sen; Xu, Mo-Yun; Zhao, Ping-Ping; Wang, Jian-Hui; Jia, Shu-Dan; Zhang, Zhong-Wei; Yuan, Shu; Lin, Hong-Hui

    2011-02-01

    Plant viruses cause many diseases that lead to significant economic losses. However, most of the approaches to control plant viruses, including transgenic processes or drugs are plant-species-limited or virus-species-limited, and not very effective. We introduce an application of jasmonic acid (JA) and salicylic acid (SA), a broad-spectrum, efficient and nontransgenic method, to improve plant resistance to RNA viruses. Applying 0.06 mM JA and then 0.1 mM SA 24 h later, enhanced resistance to Cucumber mosaic virus (CMV), Tobacco mosaic virus (TMV) and Turnip crinkle virus (TCV) in Arabidopsis, tobacco, tomato and hot pepper. The inhibition efficiency to virus replication usually achieved up to 80-90%. The putative molecular mechanism was investigated. Some possible factors affecting the synergism of JA and SA have been defined, including WRKY53, WRKY70, PDF1.2, MPK4, MPK2, MPK3, MPK5, MPK12, MPK14, MKK1, MKK2, and MKK6. All genes involving in the synergism of JA and SA were investigated. This approach is safe to human beings and environmentally friendly and shows potential as a strong tool for crop protection against plant viruses.

  4. Clearing of invasive alien plants in South Africa: a preliminary assessment of costs and progress

    CSIR Research Space (South Africa)

    Marais, R

    2004-01-01

    Full Text Available This paper provides estimates of the costs of clearing important species of invasive alien plants, as well as of progress made with clearing, based on data from a recently developed GIS-based project information system. Before the deployment...

  5. A Quantitative Method to Screen Common Bean Plants for Resistance to Bean common mosaic necrosis virus.

    Science.gov (United States)

    Strausbaugh, C A; Myers, J R; Forster, R L; McClean, P E

    2003-11-01

    ABSTRACT A quantitative method to screen common bean (Phaseolus vulgaris) plants for resistance to Bean common mosaic necrosis virus (BCMNV) is described. Four parameters were assessed in developing the quantitative method: symptoms associated with systemic virus movement, plant vigor, virus titer, and plant dry weight. Based on these parameters, two rating systems (V and VV rating) were established. Plants from 21 recombinant inbred lines (RILs) from a Sierra (susceptible) x Olathe (partially resistant) cross inoculated with the BCMNV-NL-3 K strain were used to evaluate this quantitative approach. In all, 11 RILs exhibited very susceptible reactions and 10 RILs expressed partially resistant reactions, thus fitting a 1:1 susceptible/partially resistant ratio (chi(2) = 0.048, P = 0.827) and suggesting that the response is mediated by a single gene. Using the classical qualitative approach based only on symptom expression, the RILs were difficult to separate into phenotypic groups because of a continuum of responses. By plotting mean percent reduction in either V (based on visual symptoms) or VV (based on visual symptoms and vigor) rating versus enzyme-linked immunosorbent assay (ELISA) absorbance values, RILs could be separated clearly into different phenotypic groups. The utility of this quantitative approach also was evaluated on plants from 12 cultivars or pure lines inoculated with one of three strains of BCMNV. Using the mean VV rating and ELISA absorbance values, significant differences were established not only in cultivar and pure line comparisons but also in virus strain comparisons. This quantitative system should be particularly useful for the evaluation of the independent action of bc genes, the discovery of new genes associated with partial resistance, and assessing virulence of virus strains.

  6. A Perspective on the Development of Plant-Made Vaccines in the Fight against Ebola Virus

    Science.gov (United States)

    Rosales-Mendoza, Sergio; Nieto-Gómez, Ricardo; Angulo, Carlos

    2017-01-01

    The Ebola virus (EBOV) epidemic indicated a great need for prophylactic and therapeutic strategies. The use of plants for the production of biopharmaceuticals is a concept being adopted by the pharmaceutical industry, with an enzyme for human use currently commercialized since 2012 and some plant-based vaccines close to being commercialized. Although plant-based antibodies against EBOV are under clinical evaluation, the development of plant-based vaccines against EBOV essentially remains an unexplored area. The current technologies for the production of plant-based vaccines include stable nuclear expression, transient expression mediated by viral vectors, and chloroplast expression. Specific perspectives on how these technologies can be applied for developing anti-EBOV vaccines are provided, including possibilities for the design of immunogens as well as the potential of the distinct expression modalities to produce the most relevant EBOV antigens in plants considering yields, posttranslational modifications, production time, and downstream processing. PMID:28344580

  7. Integration of plant viruses in electron beam lithography nanostructures

    International Nuclear Information System (INIS)

    Alonso, Jose M; Bittner, Alexander M; Ondarçuhu, Thierry

    2013-01-01

    Tobacco mosaic virus (TMV) is the textbook example of a virus, and also of a self-assembling nanoscale structure. This tubular RNA/protein architecture has also found applications as biotemplate for the synthesis of nanomaterials such as wires, as tubes, or as nanoparticle assemblies. Although TMV is, being a biological structure, quite resilient to environmental conditions (temperature, chemicals), it cannot be processed in electron beam lithography (eBL) fabrication, which is the most important and most versatile method of nanoscale structuring. Here we present adjusted eBL-compatible processes that allow the incorporation of TMV in nanostructures made of positive and negative tone eBL resists. The key steps are covering TMV by polymer resists, which are only heated to 50 °C, and development (selective dissolution) in carefully selected organic solvents. We demonstrate the post-lithography biochemical functionality of TMV by selective immunocoating of the viral particles, and the use of immobilized TMV as direct immunosensor. Our modified eBL process should be applicable to incorporate a wide range of sensitive materials in nanofabrication schemes. (paper)

  8. Development of RT-PCR and Nested PCR for Detecting Four Quarantine Plant Viruses Belonging to Nepovirus

    Directory of Open Access Journals (Sweden)

    Siwon Lee

    2013-09-01

    Full Text Available For quarantine purpose, we developed the RT- and nested PCR module of Tomato black ring virus (TBRV, Arabis mosaic virus (ArMV, Cherry leafroll virus (CLRV and Grapevine fanleaf virus (GFLV. The PCR modules, developed in this study make diagnosis more convenient and speedy because of same PCR condition. And also, the methods are more accurate because it can check whether the result is contamination or not using the mutation-positive control. We discard or return the 27 cases of Nepovirus infection seed by employing the module past 3 years. This study provides a rapid and useful method for detection of four quarantine plant viruses.

  9. Profile of small interfering RNAs from cotton plants infected with the polerovirus Cotton leafroll dwarf virus

    Directory of Open Access Journals (Sweden)

    Schrago Carlos EG

    2011-08-01

    Full Text Available Abstract Background In response to infection, viral genomes are processed by Dicer-like (DCL ribonuclease proteins into viral small RNAs (vsRNAs of discrete sizes. vsRNAs are then used as guides for silencing the viral genome. The profile of vsRNAs produced during the infection process has been extensively studied for some groups of viruses. However, nothing is known about the vsRNAs produced during infections of members of the economically important family Luteoviridae, a group of phloem-restricted viruses. Here, we report the characterization of a population of vsRNAs from cotton plants infected with Cotton leafroll dwarf virus (CLRDV, a member of the genus Polerovirus, family Luteoviridae. Results Deep sequencing of small RNAs (sRNAs from leaves of CLRDV-infected cotton plants revealed that the vsRNAs were 21- to 24-nucleotides (nt long and that their sequences matched the viral genome, with higher frequencies of matches in the 3- region. There were equivalent amounts of sense and antisense vsRNAs, and the 22-nt class of small RNAs was predominant. During infection, cotton Dcl transcripts appeared to be up-regulated, while Dcl2 appeared to be down-regulated. Conclusions This is the first report on the profile of sRNAs in a plant infected with a virus from the family Luteoviridae. Our sequence data strongly suggest that virus-derived double-stranded RNA functions as one of the main precursors of vsRNAs. Judging by the profiled size classes, all cotton DCLs might be working to silence the virus. The possible causes for the unexpectedly high accumulation of 22-nt vsRNAs are discussed. CLRDV is the causal agent of Cotton blue disease, which occurs worldwide. Our results are an important contribution for understanding the molecular mechanisms involved in this and related diseases.

  10. Profile of small interfering RNAs from cotton plants infected with the polerovirus Cotton leafroll dwarf virus.

    Science.gov (United States)

    Silva, Tatiane F; Romanel, Elisson A C; Andrade, Roberto R S; Farinelli, Laurent; Østerås, Magne; Deluen, Cécile; Corrêa, Régis L; Schrago, Carlos E G; Vaslin, Maite F S

    2011-08-24

    In response to infection, viral genomes are processed by Dicer-like (DCL) ribonuclease proteins into viral small RNAs (vsRNAs) of discrete sizes. vsRNAs are then used as guides for silencing the viral genome. The profile of vsRNAs produced during the infection process has been extensively studied for some groups of viruses. However, nothing is known about the vsRNAs produced during infections of members of the economically important family Luteoviridae, a group of phloem-restricted viruses. Here, we report the characterization of a population of vsRNAs from cotton plants infected with Cotton leafroll dwarf virus (CLRDV), a member of the genus Polerovirus, family Luteoviridae. Deep sequencing of small RNAs (sRNAs) from leaves of CLRDV-infected cotton plants revealed that the vsRNAs were 21- to 24-nucleotides (nt) long and that their sequences matched the viral genome, with higher frequencies of matches in the 3- region. There were equivalent amounts of sense and antisense vsRNAs, and the 22-nt class of small RNAs was predominant. During infection, cotton Dcl transcripts appeared to be up-regulated, while Dcl2 appeared to be down-regulated. This is the first report on the profile of sRNAs in a plant infected with a virus from the family Luteoviridae. Our sequence data strongly suggest that virus-derived double-stranded RNA functions as one of the main precursors of vsRNAs. Judging by the profiled size classes, all cotton DCLs might be working to silence the virus. The possible causes for the unexpectedly high accumulation of 22-nt vsRNAs are discussed. CLRDV is the causal agent of Cotton blue disease, which occurs worldwide. Our results are an important contribution for understanding the molecular mechanisms involved in this and related diseases.

  11. RNA Interference in Insect Vectors for Plant Viruses

    Directory of Open Access Journals (Sweden)

    Surapathrudu Kanakala

    2016-12-01

    Full Text Available Insects and other arthropods are the most important vectors of plant pathogens. The majority of plant pathogens are disseminated by arthropod vectors such as aphids, beetles, leafhoppers, planthoppers, thrips and whiteflies. Transmission of plant pathogens and the challenges in managing insect vectors due to insecticide resistance are factors that contribute to major food losses in agriculture. RNA interference (RNAi was recently suggested as a promising strategy for controlling insect pests, including those that serve as important vectors for plant pathogens. The last decade has witnessed a dramatic increase in the functional analysis of insect genes, especially those whose silencing results in mortality or interference with pathogen transmission. The identification of such candidates poses a major challenge for increasing the role of RNAi in pest control. Another challenge is to understand the RNAi machinery in insect cells and whether components that were identified in other organisms are also present in insect. This review will focus on summarizing success cases in which RNAi was used for silencing genes in insect vector for plant pathogens, and will be particularly helpful for vector biologists.

  12. Genetic Determinism and Evolutionary Reconstruction of a Host Jump in a Plant Virus.

    Science.gov (United States)

    Vassilakos, Nikon; Simon, Vincent; Tzima, Aliki; Johansen, Elisabeth; Moury, Benoît

    2016-02-01

    In spite of their widespread occurrence, only few host jumps by plant viruses have been evidenced and the molecular bases of even fewer have been determined. A combination of three independent approaches, 1) experimental evolution followed by reverse genetics analysis, 2) positive selection analysis, and 3) locus-by-locus analysis of molecular variance (AMOVA) allowed reconstructing the Potato virus Y (PVY; genus Potyvirus, family Potyviridae) jump to pepper (Capsicum annuum), probably from other solanaceous plants. Synthetic chimeras between infectious cDNA clones of two PVY isolates with contrasted levels of adaptation to C. annuum showed that the P3 and, to a lower extent, the CI cistron played important roles in infectivity toward C. annuum. The three analytical approaches pinpointed a single nonsynonymous substitution in the P3 and P3N-PIPO cistrons that evolved several times independently and conferred adaptation to C. annuum. In addition to increasing our knowledge of host jumps in plant viruses, this study illustrates also the efficiency of locus-by-locus AMOVA and combined approaches to identify adaptive mutations in the genome of RNA viruses. © The Author 2015. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  13. 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.

  14. Effects of Low Dose Chronic Radiation and Heavy Metals on Plants and Their Fungal and Virus Infections

    Directory of Open Access Journals (Sweden)

    A Dmitriev

    2009-06-01

    Full Text Available The effects of low dose chronic radiation on plant disease resistance and fungal and virus infections have been studied. The results obtained in the 10-km Chernobyl zone demonstrated a decrease in plant disease resistance and appearance of a "new" population of stem rust agents of cereal with a high frequency of more virulent clones. Radionuclide contamination and heavy metals lead to wider virus spread and a higher diversity of virus species. The Chernobyl zone is a territory of enhanced risk and potential threats for the environment. A special type of monitoring of microevolution processes in plant pathogens should provide better understanding of how serious these potential threats are.

  15. Disruption of plant carotenoid biosynthesis through virus-induced gene silencing affects oviposition behaviour of the butterfly Pieris rapae

    NARCIS (Netherlands)

    Zheng, S.J.; Snoeren, T.A.L.; Hogewoning, S.W.; Loon, van J.J.A.; Dicke, M.

    2010-01-01

    Optical plant characteristics are important cues to plant-feeding insects. In this article, we demonstrate for the first time that silencing the phytoene desaturase (PDS) gene, encoding a key enzyme in plant carotenoid biosynthesis, affects insect oviposition site selection behaviour. Virus-induced

  16. Geometagenomics illuminates the impact of agriculture on the distribution and prevalence of plant viruses at the ecosystem scale

    OpenAIRE

    Bernardo, Pauline; Charles-Dominique, Tristan; Barakat, Mohamed; Ortet, Philippe; Fernandez, Emmanuel; Filloux, Denis; Hartnady, Penelope; Rebelo, Tony A; Cousins, Stephen R; Mesleard, François; Cohez, Damien; Yavercovski, Nicole; Varsani, Arvind; Harkins, Gordon W; Peterschmitt, Michel

    2017-01-01

    Disease emergence events regularly result from human activities such as agriculture, which frequently brings large populations of genetically uniform hosts into contact with potential pathogens. Although viruses cause nearly 50% of emerging plant diseases, there is little systematic information about virus distribution across agro-ecological interfaces and large gaps in understanding of virus diversity in nature. Here we applied a novel landscape-scale geometagenomics approach to examine rela...

  17. Geometagenomics illuminates the impact of agriculture on the distribution and prevalence of plant viruses at the ecosystem scale

    OpenAIRE

    Bernardo, Pauline; Charles-Dominique, Tristan; Barakat, Mohamed; Ortet, Philippe; Fernandez, Emmanuel; Filloux, Denis; Hartnady, Penelope; Rebelo, Tony A.; Cousins, Stephen; Mesleard, François; Cohez, Damien; Yaverkovski, Nicole; Varsani, Arvind; Harkins, Gordon William; Peterschmitt, Michel

    2018-01-01

    Disease emergence events regularly result from human activities such as agriculture, which frequently brings large populations of genetically uniform hosts into contact with potential pathogens. Although viruses cause nearly 50% of emerging plant diseases, there is little systematic information about virus distribution across agro-ecological interfaces and large gaps in understanding of virus diversity in nature. Here we applied a novel landscape-scale geometagenomics approach to examine rela...

  18. Antiviral activity of tenofovir against Cauliflower mosaic virus and its metabolism in Brassica pekinensis plants.

    Science.gov (United States)

    Spak, Josef; Votruba, Ivan; Pavingerová, Daniela; Holý, Antonín; Spaková, Vlastimila; Petrzik, Karel

    2011-11-01

    The antiviral effect of the acyclic nucleoside phosphonate tenofovir (R)-PMPA on double-stranded DNA Cauliflower mosaic virus (CaMV) in Brassica pekinensis plants grown in vitro on liquid medium was evaluated. Double antibody sandwich ELISA and PCR were used for relative quantification of viral protein and detecting nucleic acid in plants. (R)-PMPA at concentrations of 25 and 50 mg/l significantly reduced CaMV titers in plants within 6-9 weeks to levels detectable neither by ELISA nor by PCR. Virus-free plants were obtained after 3-month cultivation of meristem tips on semisolid medium containing 50 mg/l (R)-PMPA and their regeneration to whole plants in the greenhouse. Studying the metabolism of (R)-PMPA in B. pekinensis revealed that mono- and diphosphate, structural analogs of NDP and/or NTP, are the only metabolites formed. The data indicate very low substrate activity of the enzymes toward (R)-PMPA as substrate. The extent of phosphorylation in the plant's leaves represents only 4.5% of applied labeled (R)-PMPA. In roots, we detected no radioactive peaks of phosphorylated metabolites of (R)-PMPAp or (R)-PMPApp. Copyright © 2011 Elsevier B.V. All rights reserved.

  19. Human enteric bacteria and viruses in five wastewater treatment plants in the Eastern Cape, South Africa

    Directory of Open Access Journals (Sweden)

    Olayinka Osuolale

    2017-09-01

    Full Text Available Monitoring effluents from wastewater treatment plants is important to preventing both environmental contamination and the spread of disease. We evaluated the occurrence of human enteric bacteria (faecal coliforms and Escherichia coli and viruses (rotavirus and enterovirus in the final effluents of five wastewater treatment plants (WWTPs in the Eastern Cape of South Africa. Human viruses were recovered from the effluent samples with the adsorption–elution method and detected with singleplex real-time RT–PCR assays. Rotavirus was detected in several effluents samples, but no enterovirus was detected. At WWTP-C, rotavirus titre up to 105 genome copies/L was observed and present in 41.7% of the samples. At WWTP-B, the virus was detected in 41.7% of samples, with viral titres up to 103 genome copies/L. The virus was detected once at WWTP-E, in 9% of the samples analysed. The viral titres at WWTP-A were below the detection limit in all 25% of the 1.25 L samples in which the virus was detected. Rotavirus was not observed at WWTP-D. Faecal coliform bacteria and E. coli were detected in all the WWTPs, but no correlation was established between the enteric bacteria and viruses studied. The occurrence of rotavirus in effluent samples discharged into surface waters highlights the importance of assessing viral contamination in the water sources used for domestic water use. Keywords: Rotavirus, Enterovirus, Wastewater, Eastern Cape, Effluent, Faecal coliforms and Escherichia coli

  20. Apple latent spherical virus vectors for reliable and effective virus-induced gene silencing among a broad range of plants including tobacco, tomato, Arabidopsis thaliana, cucurbits, and legumes

    International Nuclear Information System (INIS)

    Igarashi, Aki; Yamagata, Kousuke; Sugai, Tomokazu; Takahashi, Yukari; Sugawara, Emiko; Tamura, Akihiro; Yaegashi, Hajime; Yamagishi, Noriko; Takahashi, Tsubasa; Isogai, Masamichi; Takahashi, Hideki; Yoshikawa, Nobuyuki

    2009-01-01

    Apple latent spherical virus (ALSV) vectors were evaluated for virus-induced gene silencing (VIGS) of endogenous genes among a broad range of plant species. ALSV vectors carrying partial sequences of a subunit of magnesium chelatase (SU) and phytoene desaturase (PDS) genes induced highly uniform knockout phenotypes typical of SU and PDS inhibition on model plants such as tobacco and Arabidopsis thaliana, and economically important crops such as tomato, legume, and cucurbit species. The silencing phenotypes persisted throughout plant growth in these plants. In addition, ALSV vectors could be successfully used to silence a meristem gene, proliferating cell nuclear antigen and disease resistant N gene in tobacco and RCY1 gene in A. thaliana. As ALSV infects most host plants symptomlessly and effectively induces stable VIGS for long periods, the ALSV vector is a valuable tool to determine the functions of interested genes among a broad range of plant species.

  1. Progress report on installing DYMCAS in the Oak Ridge Y-12 Plant

    International Nuclear Information System (INIS)

    Mee, W.T.

    1979-01-01

    A material control and accountability system to assist in detecting diversion of special nuclear materials (SNM) was being considered by the management of the Oak Ridge Y-12 Plant in early 1975. The Dynamic Special Nuclear Materials Control and Accountability System (DYMCAS) is the product of these considerations. The evolution of computerized accountability systems for near real-time accounting of SNM will revolutionize the activities for operations and accountability departments in Y-12. The advancement of nondestructive analysis equipment with a capability for real-time input of accounting data is becoming a reality. The progress of installing the DYMCAS in a large plant processing unirradiated enriched uranium is described

  2. Progress and Problems in Understanding and Managing Primary Epstein-Barr Virus Infections

    Science.gov (United States)

    Odumade, Oludare A.; Hogquist, Kristin A.; Balfour, Henry H.

    2011-01-01

    Summary: Epstein-Barr virus (EBV) is a gammaherpesvirus that infects a large fraction of the human population. Primary infection is often asymptomatic but results in lifelong infection, which is kept in check by the host immune system. In some cases, primary infection can result in infectious mononucleosis. Furthermore, when host-virus balance is not achieved, the virus can drive potentially lethal lymphoproliferation and lymphomagenesis. In this review, we describe the biology of EBV and the host immune response. We review the diagnosis of EBV infection and discuss the characteristics and pathogenesis of infectious mononucleosis. These topics are approached in the context of developing therapeutic and preventative strategies. PMID:21233512

  3. RNA virus interference via CRISPR/Cas13a system in plants

    KAUST Repository

    Aman, Rashid

    2017-11-04

    CRISPR/Cas systems confer immunity against invading nucleic acids and phages in bacteria and archaea. CRISPR/Cas13a (known previously as C2c2) is a class 2 type VI-A ribonuclease capable of targeting and cleaving single stranded RNA (ssRNA) molecules of the phage genome. Here, we employ CRISPR/Cas13a to engineer interference with an RNA virus, Turnip Mosaic Virus (TuMV), in plants. CRISPR/Cas13a produced interference against green fluorescent protein (GFP) expressing TuMV in transient assays and stable overexpression lines of Nicotiana benthamiana. crRNAs targeting the HC-Pro and GFP sequences exhibited better interference than those targeting other regions such as coat protein (CP) sequence. Cas13a can also process pre-crRNAs into functional crRNAs. Our data indicate that CRISPR/Cas13a can be used for engineering interference against RNA viruses, providing a potential novel mechanism for RNA-guided immunity against RNA viruses, and for other RNA manipulations in plants.

  4. RNA virus interference via CRISPR/Cas13a system in plants

    KAUST Repository

    Aman, Rashid

    2018-01-04

    CRISPR/Cas systems confer immunity against invading nucleic acids and phages in bacteria and archaea. CRISPR/Cas13a (known previously as C2c2) is a class 2 type VI-A ribonuclease capable of targeting and cleaving single-stranded RNA (ssRNA) molecules of the phage genome. Here, we employ CRISPR/Cas13a to engineer interference with an RNA virus, Turnip Mosaic Virus (TuMV), in plants.CRISPR/Cas13a produces interference against green fluorescent protein (GFP)-expressing TuMV in transient assays and stable overexpression lines of Nicotiana benthamiana. CRISPR RNA (crRNAs) targeting the HC-Pro and GFP sequences exhibit better interference than those targeting other regions such as coat protein (CP) sequence. Cas13a can also process pre-crRNAs into functional crRNAs.Our data indicate that CRISPR/Cas13a can be used for engineering interference against RNA viruses, providing a potential novel mechanism for RNA-guided immunity against RNA viruses and for other RNA manipulations in plants.

  5. A plant virus movement protein forms ringlike complexes with the major nucleolar protein, fibrillarin, in vitro.

    Science.gov (United States)

    Canetta, Elisabetta; Kim, Sang Hyon; Kalinina, Natalia O; Shaw, Jane; Adya, Ashok K; Gillespie, Trudi; Brown, John W S; Taliansky, Michael

    2008-02-29

    Fibrillarin, one of the major proteins of the nucleolus, has methyltransferase activity directing 2'-O-ribose methylation of rRNA and snRNAs and is required for rRNA processing. The ability of the plant umbravirus, groundnut rosette virus, to move long distances through the phloem, the specialized plant vascular system, has been shown to strictly depend on the interaction of one of its proteins, the ORF3 protein (protein encoded by open reading frame 3), with fibrillarin. This interaction is essential for several stages in the groundnut rosette virus life cycle such as nucleolar import of the ORF3 protein via Cajal bodies, relocalization of some fibrillarin from the nucleolus to cytoplasm, and assembly of cytoplasmic umbraviral ribonucleoprotein particles that are themselves required for the long-distance spread of the virus and systemic infection. Here, using atomic force microscopy, we determine the architecture of these complexes as single-layered ringlike structures with a diameter of 18-22 nm and a height of 2.0+/-0.4 nm, which consist of several (n=6-8) distinct protein granules. We also estimate the molar ratio of fibrillarin to ORF3 protein in the complexes as approximately 1:1. Based on these data, we propose a model of the structural organization of fibrillarin-ORF3 protein complexes and discuss potential mechanistic and functional implications that may also apply to other viruses.

  6. I. Identification and characterization of dasheen mosaic virus in Chinese evergreen plants (Aglaonema commutatum) in California. II. New approaches for detecting plant viruses

    International Nuclear Information System (INIS)

    Kositratana, W.

    1985-01-01

    Chinese evergreen plants (Aglaonema commutatum) with symptoms of mild stunting, chlorosis, leaf distortion and mosaic, were observed in Southern California. Flexuous rods (ca. 750 nm) were detected in leaf dip and partially purified preparations. Dasheen mosac virus (DMV) was identified as the causal agent on the basis of host range, morphology and reaction with DMV antiserum in immunodouble diffusion and immunosorbent electron microscopy (ISEM) tests. Tetragonia expansa was found to be a new host of this virus. Surveys indicate that DMV is not widespread in cultivars of A. commutatum in Southern California. The virus was purified from leaves of seedling Philodendron selloum by clarification with CCl 4 , CHCl 3 , and Triton X-100, precipitation with PEG-8000 and centrifugation in either Cs 2 SO 4 -sucrose cushion gradients or Cs 2 SO 4 equilibrium density gradients. Purified virions formed a single UV-absorbing infectious band with densities of 1.31 and 1.245 g/ml in CsCl 2 and Cs 2 SO 4 equilibrium density gradients, respectively, and a sedimentation coefficient of 154 S as determined by a linear-log sucrose density gradient centrifugation. Dasheen mosaic virus has a plus-sense ssRNA with the M.W. of 3.2 x 10 6 under denaturing conditions. Molecular hybridization analysis using 3 H-complementary DNA specific to DMV-Ca RNA showed that DMV-Ca isolate was more closely related to DMV-Fiji isolate than to DMV-Fla isolate, and was very distantly related to ZYMV, TEV. PeMoC and PVY

  7. Signal validation for nuclear power plants: Progress report No. 8, January--March 1989

    International Nuclear Information System (INIS)

    Upadhyaya, B.R.; Kerlin, T.W.

    1989-01-01

    This report is a summary of the progress in the US Department of Energy sponsored project on Signal Validation for Nuclear Power Plants, for the period January--March, 1989. This is the last phase of the project with September 29, 1989 as the official ending date. A preliminary draft of a two-volume final report is scheduled for release in mid-September

  8. Loop-mediated Isothermal Amplification Assay to Rapidly Detect Wheat Streak Mosaic Virus in Quarantined Plants

    Directory of Open Access Journals (Sweden)

    Siwon Lee

    2015-12-01

    Full Text Available We developed a loop-mediated isothermal amplification (LAMP method to rapidly diagnose Wheat streak mosaic virus (WSMV during quarantine inspections of imported wheat, corn, oats, and millet. The LAMP method was developed as a plant quarantine inspection method for the first time, and its simplicity, quickness, specificity and sensitivity were verified compared to current reverse transcription-polymerase chain reaction (RT-PCR and nested PCR quarantine methods. We were able to quickly screen for WSMV at quarantine sites with many test samples; thus, this method is expected to contribute to plant quarantine inspections.

  9. Hepatitis E Virus Genotype 4 Sequences Detected in Sewage from Treatment Plants of China

    OpenAIRE

    Li, Heng; Li, Wei; She, Ruiping; Yu, Liang; Wu, Qiaoxing; Yang, Jingling; Hu, Fengjiao; Soomro, Majid Hussain; Shi, Ruihan; Hao, Wenzhuo; Zhao, Yue; Mao, Jingjing

    2017-01-01

    The aim of this study was to investigate the occurrence of hepatitis E virus (HEV) in sewage samples in Shen Zhen, China. Sewage samples were collected from 152 sewage plants including livestock sewage, domestic sewage and treated sewage from May to July of 2015. Two of 152 samples were HEV positive (1.32%) from the livestock sewage plants. Partial ORF2 fragments of HEV were sequenced and a phylogenetic tree was constructed using MEGA5.1. Blast and phylogenetic analyses showed that both of th...

  10. 寨卡病毒研究进展%RESEARCH PROGRESS OF ZIKA VIRUS

    Institute of Scientific and Technical Information of China (English)

    王刚; 郑伟; 杨永耀

    2016-01-01

    Zika virus is transmitted to humans primarily through the bite of an infected Aedes mosquito. People with Zika virus disease usually have symptoms that can include mild fever, skin rashes, conjunctivitis, muscle and joint pain, malaise or headache, and pregnant woman infected with Zika virus disease usually cause newborn babies with microcephaly. At present, the Zika virus has becoming from a localized problem to a global threat. The paper reviewed Zika virus on epidemiology, clinical research, main vectors and so on, in order to provide control measure for Zika virus.%寨卡病毒是一种主要由伊蚊传播的蚊媒病毒,感染该病毒后的主要症状包括低热、斑丘疹、关节疼痛、结膜炎等,并且有造成神经和自身免疫系统并发症的风险,孕妇感染寨卡病毒常导致新生儿小头畸形。目前寨卡病毒有全球扩散风险。本文就寨卡病毒病的流行病学、临床研究、传播媒介以及防控等研究现状进行综述,以期对寨卡的防治提供借鉴。

  11. Chlorophyll fluorescence lifetime imaging provides new insight into the chlorosis induced by plant virus infection.

    Science.gov (United States)

    Lei, Rong; Jiang, Hongshan; Hu, Fan; Yan, Jin; Zhu, Shuifang

    2017-02-01

    Leaf chlorosis induced by plant virus infection has a short fluorescence lifetime, which reflects damaged photosynthetic complexes and degraded chloroplasts. Plant viruses often induce chlorosis and necrosis, which are intimately related to photosynthetic functions. Chlorophyll fluorescence lifetime measurement is a valuable noninvasive tool for analyzing photosynthetic processes and is a sensitive indicator of the environment surrounding the fluorescent molecules. In this study, our central goal was to explore the effect of viral infection on photosynthesis by employing chlorophyll fluorescence lifetime imaging (FLIM), steady-state fluorescence, non-photochemical quenching (NPQ), transmission electron microscopy (TEM), and pigment analysis. The data indicated that the chlorophyll fluorescence lifetime of chlorotic leaves was significantly shorter than that of healthy control leaves, and the fitted short lifetime component of chlorophyll fluorescence of chlorotic leaves was dominant. This dominant short lifetime component may result from damage to the structure of thylakoid, which was confirmed by TEM. The NPQ value of chlorotic leaves was slightly higher than that of healthy green leaves, which can be explained by increased neoxanthin, lutein and violaxanthin content relative to chlorophyll a. The difference in NPQ is slight, but FLIM can provide simple and direct characterization of PSII structure and photosynthetic function. Therefore, this technique shows great potential as a simple and rapid method for studying mechanisms of plant virus infection.

  12. Incidence of infection in 39-month-old ewes with TMEM154 diplotypes "1 1," "1 3," and "3 3" after natural exposure to ovine progressive pneumonia virus

    Science.gov (United States)

    Production and well-being of sheep and goats in many countries are harmfully impacted by small ruminant lentiviruses (SRLV) that cause incurable, progressive diseases. Susceptibility to ovine progressive pneumonia virus (OPPV), the North American form of SRLV, is influenced by variants of the ovine...

  13. Improving human reliability through better nuclear power plant system design. Progress report

    International Nuclear Information System (INIS)

    Golay, M.W.

    1995-01-01

    The project on open-quotes Development of a Theory of the Dependence of Human Reliability upon System Designs as a Means of Improving Nuclear Power Plant Performanceclose quotes has been undertaken in order to address the important problem of human error in advanced nuclear power plant designs. Most of the creativity in formulating such concepts has focused upon improving the mechanical reliability of safety related plant systems. However, the lack of a mature theory has retarded similar progress in reducing the likely frequencies of human errors. The main design mechanism used to address this class of concerns has been to reduce or eliminate the human role in plant operations and accident response. The plan of work being pursued in this project is to perform a set of experiments involving human subject who are required to operate, diagnose and respond to changes in computer-simulated systems, relevant to those encountered in nuclear power plants. In the tests the systems are made to differ in complexity in a systematic manner. The computer program used to present the problems to be solved also records the response of the operator as it unfolds. Ultimately this computer is also to be used in compiling the results of the project. The work of this project is focused upon nuclear power plant applications. However, the persuasiveness of human errors in using all sorts of electromechanical machines gives it a much greater potential importance. Because of this we are attempting to pursue our work in a fashion permitting broad generalizations

  14. Disease progression and health care resource consumption in patients affected by hepatitis C virus in real practice setting

    Directory of Open Access Journals (Sweden)

    Perrone V

    2016-10-01

    Full Text Available Valentina Perrone, Diego Sangiorgi, Stefano Buda, Luca Degli Esposti CliCon S.r.l. Health, Economics & Outcomes Research, Ravenna, Italy Introduction: Hepatitis C virus (HCV infection represents serious health problems worldwide and is a major contributor to end-stage liver disease including cirrhosis and hepatocellular carcinoma (HCC. In Italy, ~2% of subjects are infected with HCV. The objective of this study was to describe treatment patterns, disease progression, and resource use in HCV.Methods: An observational retrospective cohort analysis based on four Local Health Units administrative and laboratory databases was conducted. HCV-positive patients between January 1, 2009 and December 31, 2010 were included and followed-up for 1 year. To explore which covariates were associated to disease progression (cirrhosis, HCC, death for any cause, Cox proportional hazards models were performed.Results: A total of 9,514 patients were analyzed of which 55.6% were male, aged 58.1±16.1, and prevalence 0.4%; 5.8% were positive to human immunodeficiency virus (HIV infection, 3.0% to hepatitis B virus (HBV, and 1.6% to HCV+HBV+HIV; 26.1% had cirrhosis and 4.3% HCC. The majority of patients (76% did not receive an antiviral treatment; the main factors affecting this decision were age, 44.1% of untreated patients being aged >65 years; 31% were affected by cirrhosis, 6.6% had ongoing substance or alcohol abuse, and 5.5% were affected by HCC. Disease progression in the observed timeframe was less frequent among treated patients (incidence rate per 100 patients/year: cirrhosis 2.1±0.7 vs 13.0±1.0, HCC 0.5±0.3 vs 3.6±0.5, death 0.5±0.3 vs 6.4±0.7. The annual expenditure for HCV management (drugs, hospitalizations, outpatient services was €4,700 per patient.Conclusion: This observational, real-life study shows that only a small proportion of patients received antiviral therapy in the territorial services investigated; among patients who were not treated

  15. CRYOTHERAPY: A NEW TECHNIQUE TO OBTAIN GRAPEVINE PLANTS FREE OF VIRUSES

    Directory of Open Access Journals (Sweden)

    JEAN CARLOS BETTONI

    2016-01-01

    Full Text Available ABSTRACT Through in vitro tissue culture techniques it is possible to propagate high quality nursery plants faster. Cryotherapy is a promising tool, based on in vitro culture techniques, for achieving in a short time, high frequency of regenerating plants free of viruses. The objective of this review is to present and analyze the results of research conducted in cryotherapy methods based on cryopreservation protocols for recovery of cultivars free of micro-organisms with potential agronomic interest. The main methods employed in cryotherapy are encapsulation-dehydration, vitrification, encapsulation-vitrification and droplet vitrification, which are based on the immersion of preconditioned shoot tips in liquid nitrogen, followed by their recovery in vitro on to culture media for regeneration of healthy plantlets. Improvements to cryotherapy protocols used for grapevine are still needed, since there are variations in response according to the genotype. The published research mostly relates to Vitis vinifera and the few studies applied to other species show that the protocols need to be improved. This specificity goes beyond species, with different responses among cultivars, limiting the broader application of the technology. On the other hand, traditional methods used for virus removal from infected plant materials also have limitations and therefore investment in research for the development and application of cryopreservation techniques is highly justified, considering its efficiency and low-cost, once the protocols are developed. High frequency of virus-free plants among regenerants within a short time frame is the most desirable aspect of cryotherapy. Therefore, these advantages make the technique a promising tool for institutions mandated to the development of high-health planting materials with high genetic and agronomic potential for viticulture.

  16. An internet-based bioinformatics toolkit for plant biosecurity diagnosis and surveillance of viruses and viroids.

    Science.gov (United States)

    Barrero, Roberto A; Napier, Kathryn R; Cunnington, James; Liefting, Lia; Keenan, Sandi; Frampton, Rebekah A; Szabo, Tamas; Bulman, Simon; Hunter, Adam; Ward, Lisa; Whattam, Mark; Bellgard, Matthew I

    2017-01-11

    Detection and preventing entry of exotic viruses and viroids at the border is critical for protecting plant industries trade worldwide. Existing post entry quarantine screening protocols rely on time-consuming biological indicators and/or molecular assays that require knowledge of infecting viral pathogens. Plants have developed the ability to recognise and respond to viral infections through Dicer-like enzymes that cleave viral sequences into specific small RNA products. Many studies reported the use of a broad range of small RNAs encompassing the product sizes of several Dicer enzymes involved in distinct biological pathways. Here we optimise the assembly of viral sequences by using specific small RNA subsets. We sequenced the small RNA fractions of 21 plants held at quarantine glasshouse facilities in Australia and New Zealand. Benchmarking of several de novo assembler tools yielded SPAdes using a kmer of 19 to produce the best assembly outcomes. We also found that de novo assembly using 21-25 nt small RNAs can result in chimeric assemblies of viral sequences and plant host sequences. Such non-specific assemblies can be resolved by using 21-22 nt or 24 nt small RNAs subsets. Among the 21 selected samples, we identified contigs with sequence similarity to 18 viruses and 3 viroids in 13 samples. Most of the viruses were assembled using only 21-22 nt long virus-derived siRNAs (viRNAs), except for one Citrus endogenous pararetrovirus that was more efficiently assembled using 24 nt long viRNAs. All three viroids found in this study were fully assembled using either 21-22 nt or 24 nt viRNAs. Optimised analysis workflows were customised within the Yabi web-based analytical environment. We present a fully automated viral surveillance and diagnosis web-based bioinformatics toolkit that provides a flexible, user-friendly, robust and scalable interface for the discovery and diagnosis of viral pathogens. We have implemented an automated viral surveillance and

  17. 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.

  18. Serum albumin 'camouflage' of plant virus based nanoparticles prevents their antibody recognition and enhances pharmacokinetics.

    Science.gov (United States)

    Pitek, Andrzej S; Jameson, Slater A; Veliz, Frank A; Shukla, Sourabh; Steinmetz, Nicole F

    2016-05-01

    Plant virus-based nanoparticles (VNPs) are a novel class of nanocarriers with unique potential for biomedical applications. VNPs have many advantageous properties such as ease of manufacture and high degree of quality control. Their biocompatibility and biodegradability make them an attractive alternative to synthetic nanoparticles (NPs). Nevertheless, as with synthetic NPs, to be successful in drug delivery or imaging, the carriers need to overcome several biological barriers including innate immune recognition. Plasma opsonization can tag (V)NPs for clearance by the mononuclear phagocyte system (MPS), resulting in shortened circulation half lives and non-specific sequestration in non-targeted organs. PEG coatings have been traditionally used to 'shield' nanocarriers from immune surveillance. However, due to broad use of PEG in cosmetics and other industries, the prevalence of anti-PEG antibodies has been reported, which may limit the utility of PEGylation in nanomedicine. Alternative strategies are needed to tailor the in vivo properties of (plant virus-based) nanocarriers. We demonstrate the use of serum albumin (SA) as a viable alternative. SA conjugation to tobacco mosaic virus (TMV)-based nanocarriers results in a 'camouflage' effect more effective than PEG coatings. SA-'camouflaged' TMV particles exhibit decreased antibody recognition, as well as enhanced pharmacokinetics in a Balb/C mouse model. Therefore, SA-coatings may provide an alternative and improved coating technique to yield (plant virus-based) NPs with improved in vivo properties enhancing drug delivery and molecular imaging. Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. Which Plant Proteins Are Involved in Antiviral Defense? Review on In Vivo and In Vitro Activities of Selected Plant Proteins against Viruses

    Directory of Open Access Journals (Sweden)

    Oskar Musidlak

    2017-11-01

    Full Text Available Plants have evolved a variety of defense mechanisms to tackle virus attack. Endogenous plant proteins can function as virus suppressors. Different types of proteins mediate defense responses against plant viruses. Pathogenesis-related (PR proteins are activated upon pathogen infections or in different stress situations and their production is one of many components in plant defense. Ribosome-inactivating proteins (RIPs suppress translation by enzymatically damaging ribosomes and they have been found to have antiviral activity. RNA-binding proteins (RBPs bind to target RNAs via specialized RNA-binding domain and can directly or indirectly function in plant defense system against RNA viruses. Proteins involved in silencing machinery, namely Dicer-like (DCL proteins, Argonaute (AGO proteins, and RNA-dependent RNA polymerases (RDRs confer innate antiviral defense in plants as they are able to degrade foreign RNA of viral origin. This review aims to provide a comprehensive and up-to-date picture of plant proteins participating in antiviral defense. As a result we discuss proteins conferring plant antiviral resistance and their potential future applications in different fields of life including agriculture and medicine.

  20. Arabidopsis thaliana plants expressing Rift Valley fever virus antigens: Mice exhibit systemic immune responses as the result of oral administration of the transgenic plants.

    Science.gov (United States)

    Kalbina, Irina; Lagerqvist, Nina; Moiane, Bélisario; Ahlm, Clas; Andersson, Sören; Strid, Åke; Falk, Kerstin I

    2016-11-01

    The zoonotic Rift Valley fever virus affects livestock and humans in Africa and on the Arabian Peninsula. The economic impact of this pathogen due to livestock losses, as well as its relevance to public health, underscores the importance of developing effective and easily distributed vaccines. Vaccines that can be delivered orally are of particular interest. Here, we report the expression in transformed plants (Arabidopsis thaliana) of Rift Valley fever virus antigens. The antigens used in this study were the N protein and a deletion mutant of the Gn glycoprotein. Transformed lines were analysed for specific mRNA and protein content by RT-PCR and Western blotting, respectively. Furthermore, the plant-expressed antigens were evaluated for their immunogenicity in mice fed the transgenic plants. After oral intake of fresh transgenic plant material, a proportion of the mice elicited specific IgG antibody responses, as compared to the control animals that were fed wild-type plants and of which none sero-converted. Thus, we show that transgenic plants can be readily used to express and produce Rift Valley Fever virus proteins, and that the plants are immunogenic when given orally to mice. These are promising findings and provide a basis for further studies on edible plant vaccines against the Rift Valley fever virus. Copyright © 2016 Elsevier Inc. All rights reserved.

  1. Plant growth retardation and conserved miRNAs are correlated to Hibiscus chlorotic ringspot virus infection.

    Science.gov (United States)

    Gao, Ruimin; Wan, Zi Yi; Wong, Sek-Man

    2013-01-01

    Virus infection may cause a multiplicity of symptoms in their host including discoloration, distortion and growth retardation. Hibiscus chlorotic ringspot virus (HCRSV) infection was studied using kenaf (Hibiscus cannabinus L.), a non-wood fiber-producing crop in this study. Infection by HCRSV reduced the fiber yield and concomitant economic value of kenaf. We investigated kenaf growth retardation and fluctuations of four selected miRNAs after HCRSV infection. Vegetative growth (including plant height, leaf size and root development) was severely retarded. From the transverse and radial sections of the mock and HCRSV-infected kenaf stem, the vascular bundles of HCRSV-infected plants were severely disrupted. In addition, four conserved plant developmental and defence related microRNAs (miRNAs) (miR165, miR167, miR168 and miR171) and their respective target genes phabulosa (PHB), auxin response factor 8 (ARF8), argonaute 1 (AGO1) and scarecrow-like protein 1 (SCL1) displayed variation in expression levels after HCRSV infection. Compared with the mock inoculated kenaf plants, miR171 and miR168 and their targets SCL1 and AGO1 showed greater fluctuations after HCRSV infection. As HCRSV upregulates plant SO transcript in kenaf and upregulated AGO1 in HCRSV-infected plants, the expression level of AGO1 transcript was further investigated under sulfite oxidase (SO) overexpression or silencing condition. Interestingly, the four selected miRNAs were also up- or down-regulated upon overexpression or silencing of SO. Plant growth retardation and fluctuation of four conserved miRNAs are correlated to HCRSV infection.

  2. Epstein-Barr virus BGLF4 kinase retards cellular S-phase progression and induces chromosomal abnormality.

    Directory of Open Access Journals (Sweden)

    Yu-Hsin Chang

    Full Text Available Epstein-Barr virus (EBV induces an uncoordinated S-phase-like cellular environment coupled with multiple prophase-like events in cells replicating the virus. The EBV encoded Ser/Thr kinase BGLF4 has been shown to induce premature chromosome condensation through activation of condensin and topoisomerase II and reorganization of the nuclear lamina to facilitate the nuclear egress of nucleocapsids in a pathway mimicking Cdk1. However, the observation that RB is hyperphosphorylated in the presence of BGLF4 raised the possibility that BGLF4 may have a Cdk2-like activity to promote S-phase progression. Here, we investigated the regulatory effects of BGLF4 on cell cycle progression and found that S-phase progression and DNA synthesis were interrupted by BGLF4 in mammalian cells. Expression of BGLF4 did not compensate Cdk1 defects for DNA replication in S. cerevisiae. Using time-lapse microscopy, we found the fate of individual HeLa cells was determined by the expression level of BGLF4. In addition to slight cell growth retardation, BGLF4 elicits abnormal chromosomal structure and micronucleus formation in 293 and NCP-TW01 cells. In Saos-2 cells, BGLF4 induced the hyperphosphorylation of co-transfected RB, while E2F1 was not released from RB-E2F1 complexes. The E2F1 regulated activities of the cyclin D1 and ZBRK1 promoters were suppressed by BGLF4 in a dose dependent manner. Detection with phosphoamino acid specific antibodies revealed that, in addition to Ser780, phosphorylation of the DNA damage-responsive Ser612 on RB was enhanced by BGLF4. Taken together, our study indicates that BGLF4 may directly or indirectly induce a DNA damage signal that eventually interferes with host DNA synthesis and delays S-phase progression.

  3. Research progress of Zika virus disease%寨卡病毒病研究进展

    Institute of Scientific and Technical Information of China (English)

    管晓庆; 陈志海

    2017-01-01

    Zika virus disease is caused by Zika virus transmitted by Aedes mosquitoes. The virus is mainly transmitted by the bite of Aedes Aegypti and Ae. Albopictu, and mounting evidence has shown the possibility of sexual transmission and maternofetal transmission. The clinical presentation of Zika virus disease is nonspecific,including rash, fever, conjunctivitis, arthralgia, etc. The emergence of Zika virus is associated with the description of severe neurological complications, microcephaly in neonates and Guillian-Barre syndrome in adults. Laboratory diagnosis of Zika virus disease relies on the detection of viral nucleic acid by real-tirne PCR and the detection of IgM antibodies by enzyme-linked immunosorbent assay (ELISA). There is no specific treatment or vaccine currently available for this disease, Prevention measures are mainly individual protection from mosquito bites and vector control.%寨卡病毒病是由寨卡病毒引起的一种自限性急性传染病.寨卡病毒主要通过埃及伊蚊和白纹伊蚊叮咬传播,有证据表明也可通过性传播和母婴传播.临床表现主要为皮疹、发热、关节痛或结膜炎等非特异性症状,但寨卡病毒感染与新生儿小头畸形、格林-巴利综合征等存在密切关系.实验室检测方法包括实时荧光定量PCR检测病毒核酸和ELISA检测IgM抗体.该疾病目前无有效的抗病毒药物和疫苗.预防措施主要为预防蚊虫叮咬和采取虫媒控制措施.

  4. Detection of polyoma virus in brain tissue of patients with progressive multifocal leukoencephalopathy by real-time PCR and pyrosequencing.

    Science.gov (United States)

    Beck, Rose C; Kohn, Debra J; Tuohy, Marion J; Prayson, Richard A; Yen-Lieberman, Belinda; Procop, Gary W

    2004-03-01

    We evaluated 2 methods, a LightCycler PCR assay and pyrosequencing for the detection of the JC polyoma virus (JCV) in fixed brain tissue of 10 patients with and 3 control patients without progressive multifocal leukoencephalopathy (PML). Nucleic acid extraction was performed after deparaffinization and proteinase K digestion. The LightCycler assay differentiates the BK virus (BKV), JCV, and SV40 using melt curve analysis. Conventional PCR was used with the same primers to generate products for pyrosequencing. Two sequencing primers were used that differentiate the polyoma viruses. Seven of 11 biopsies (1 patient had 2 biopsies) with PML were positive for JCV by real-time PCR and/or PCR/pyrosequencing. Three of 4 remaining biopsies were positive by real-time PCR but had melting points between JCV and SV40. The 4 specimens that were negative or atypical by LightCycler PCR were positive by traditional PCR, but 1 had an amplicon of lower molecular weight by gel electrophoresis. These were shown to represent JCV by at least 1 of the 2 pyrosequencing primers. The biopsies from patients without PML were PCR negative. Both the LightCycler and pyrosequencing assays are useful for confirming JCV in brain biopsies from patients with PML, but variant JCVs may require supplementary methods to confirm JCV infection.

  5. Recessive Resistance to Plant Viruses: Potential Resistance Genes Beyond Translation Initiation Factors

    Directory of Open Access Journals (Sweden)

    Masayoshi Hashimoto

    2016-10-01

    Full Text Available The ability of plant viruses to propagate their genomes in host cells depends on many host factors. In the absence of an agrochemical that specifically targets plant viral infection cycles, one of the most effective methods for controlling viral diseases in plants is taking advantage of the host plant’s resistance machinery. Recessive resistance is conferred by a recessive gene mutation that encodes a host factor critical for viral infection. It is a branch of the resistance machinery and, as an inherited characteristic, is very durable. Moreover, recessive resistance may be acquired by a deficiency in a negative regulator of plant defense responses, possibly due to the autoactivation of defense signaling. Eukaryotic translation initiation factor (eIF 4E and eIF4G and their isoforms are the most widely exploited recessive resistance genes in several crop species, and they are effective against a subset of viral species. However, the establishment of efficient, recessive resistance-type antiviral control strategies against a wider range of plant viral diseases requires genetic resources other than eIF4Es. In this review, we focus on recent advances related to antiviral recessive resistance genes evaluated in model plants and several crop species. We also address the roles of next-generation sequencing and genome editing technologies in improving plant genetic resources for recessive resistance-based antiviral breeding in various crop species.

  6. Progress in the integration of the ITER plant systems in auxiliary buildings

    International Nuclear Information System (INIS)

    Kotamäki, M.; Cordier, J.-J.; Kuehn, I.; Perrin, J.-L.; Sweeney, S.; Villedary, B.

    2016-01-01

    Highlights: • Usage of 3D CAD model in ITER configuration management presented. • 3D CAD models efficient in configuration and interface management. • Costly and schedule delaying changes avoided with proper interface management. • ITER buildings construction progressing. - Abstract: The ITER Tokamak machine is located in the center of Tokamak complex buildings consisting of Tokamak, Diagnostic, and Tritium buildings. Around the Tokamak complex there are over 30 auxiliary buildings housing various plant systems serving the Tokamak machine either directly or indirectly. The layout and space allocation of each auxiliary building and plant systems housed by the building are represented in the so-called Configuration Management Models (CMM). These are light 3D CAD models that define the required space envelope and the physical interfaces between the systems and the buildings and in-between the systems. The paper describes the CMM and interface management processes of the ITER auxiliary buildings and plant systems, and discusses the preparations for the plant installation phase. In addition, the current baseline configuration of the ITER plant systems in auxiliary buildings is described together with the recent developments in the configuration of different systems, as well as the current status of the construction of the buildings.

  7. Progress in the integration of the ITER plant systems in auxiliary buildings

    Energy Technology Data Exchange (ETDEWEB)

    Kotamäki, M., E-mail: miikka.kotamaki@iter.org; Cordier, J.-J.; Kuehn, I.; Perrin, J.-L.; Sweeney, S.; Villedary, B.

    2016-11-01

    Highlights: • Usage of 3D CAD model in ITER configuration management presented. • 3D CAD models efficient in configuration and interface management. • Costly and schedule delaying changes avoided with proper interface management. • ITER buildings construction progressing. - Abstract: The ITER Tokamak machine is located in the center of Tokamak complex buildings consisting of Tokamak, Diagnostic, and Tritium buildings. Around the Tokamak complex there are over 30 auxiliary buildings housing various plant systems serving the Tokamak machine either directly or indirectly. The layout and space allocation of each auxiliary building and plant systems housed by the building are represented in the so-called Configuration Management Models (CMM). These are light 3D CAD models that define the required space envelope and the physical interfaces between the systems and the buildings and in-between the systems. The paper describes the CMM and interface management processes of the ITER auxiliary buildings and plant systems, and discusses the preparations for the plant installation phase. In addition, the current baseline configuration of the ITER plant systems in auxiliary buildings is described together with the recent developments in the configuration of different systems, as well as the current status of the construction of the buildings.

  8. Differentially expressed genes in healthy and plum pox virus-infected Nicotiana benthamiana plants.

    Science.gov (United States)

    Vozárová, Z; Žilová, M; Šubr, Z

    2015-12-01

    Viruses use both material and energy sources of their hosts and redirect the production of disposable compounds in order to make viral replication more efficient. Metabolism of infected organisms is modified by these enhanced requirements as well by their own defense response. Resulting complex story consists of many regulation events on various gene expression levels. Elucidating these processes may contribute to the knowledge on virus-host interactions and to evolving new antiviral strategies. In our work we applied a subtractive cloning technique to compare the transcriptomes of healthy and plum pox virus (PPV)-infected Nicotiana benthamiana plants. Several genes were found to be induced or repressed by the PPV infection. The induced genes were mainly related to general stress response or photosynthesis, several repressed genes could be connected with growth defects evoked by the infection. Interestingly, some genes usually up-regulated by fungal or bacterial infection were found repressed in PPV-infected plants. Potential involvement of particular differently expressed genes in the process of PPV infection is discussed.

  9. In Silico Screening Hepatitis B Virus DNA Polymerase Inhibitors from Medicinal Plants

    Directory of Open Access Journals (Sweden)

    Mokhtar Nosrati

    2017-08-01

    Full Text Available Abstract Background: Hepatitis B virus infection (HBV is a significant global health problem and is a major cause of morbidity and mortality worldwide. Therefore, currently, introducing novel anti Hepatitis B drugs is taken into consideration. This study was planned to in silico screening novel Hepatitis B virus DNA polymerase inhibitors from two medicinal plants Terminalis chebula and Caesalpinia sappan. Materials and Methods: This is a descriptive-analytic study. In the study, three-dimensional structure of the Hepatitis B virus DNA polymerase was predicted using homology modeling method. A set of phytochemicals from mentioned plants were retrieved from Pubchem database in SDF format. In silico screening was carried out using molecular docking between mentioned phytochemicals and modeled polymerase by iGemdock 2.1 software. Results: Results of the study confirmed that all evaluated ligands have appropriate interactions to the polymerase with least toxicity and without genotoxicity potential. Results also showed that most interactions occur in reverse transcriptase domain which located in 354-694 area in the amino acid sequence of tested polymerase. Analysis of energy and amino acids involved in ligand-polymerase interaction revealed that Terchebin, Chebulinic Acid and Terflavin A have more effective interaction with the polymerase in compared to other ligands. Conclusion: Based on the results it can be concluded that evaluated compounds could be good candidates for in vitro and in vivo research in order to develop novel anti- Hepatitis B drugs.

  10. 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.

  11. Plant rhabdoviruses: new insights and research needs in the interplay of negative-strand RNA viruses with plant and insect hosts.

    Science.gov (United States)

    Mann, Krin S; Dietzgen, Ralf G

    2014-08-01

    Rhabdoviruses are taxonomically classified in the family Rhabdoviridae, order Mononegavirales. As a group, rhabdoviruses can infect plants, invertebrates and vertebrates. Plant cyto- and nucleorhabdoviruses infect a wide variety of species across both monocot and dicot families, including agriculturally important crops such as lettuce, wheat, barley, rice, maize, potato and tomato. Plant rhabdoviruses are transmitted by and replicate in hemipteran insects such as aphids (Aphididae), leafhoppers (Cicadellidae), or planthoppers (Delphacidae). These specific interactions between plants, viruses and insects offer new insights into host adaptation and molecular virus evolution. This review explores recent advances as well as knowledge gaps in understanding of replication, RNA silencing suppression and movement of plant rhabdoviruses with respect to both plant and insect hosts.

  12. Expression of human immunodeficiency virus in cerebrospinal fluid of children with progressive encephalopathy

    NARCIS (Netherlands)

    Epstein, L. G.; Goudsmit, J.; Paul, D. A.; Morrison, S. H.; Connor, E. M.; Oleske, J. M.; Holland, B.

    1987-01-01

    The retrovirus that causes acquired immune deficiency syndrome (AIDS) is now designated the human immunodeficiency virus (HIV). The cerebrospinal fluid (CSF) of 27 children with HIV infection was assayed for intra-blood-brain barrier (IBBB) synthesis of HIV-specific antibodies and for the presence

  13. Simian virus 40, poliovirus vaccines, and human cancer: research progress versus media and public interests

    Science.gov (United States)

    Butel, J. S.

    2000-01-01

    From 1955 through early 1963, millions of people were inadvertently exposed to simian virus 40 (SV40) as a contaminant of poliovirus vaccines; the virus had been present in the monkey kidney cultures used to prepare the vaccines and had escaped detection. SV40 was discovered in 1960 and subsequently eliminated from poliovirus vaccines. This article reviews current knowledge about SV40 and considers public responses to reports in the media. SV40 is a potent tumour virus with broad tissue tropism that induces tumours in rodents and transforms cultured cells from many species. It is also an important laboratory model for basic studies of molecular processes in eukaryotic cells and mechanisms of neoplastic transformation. SV40 neutralizing antibodies have been detected in individuals not exposed to contaminated poliovirus vaccines. There have been many reports of detection of SV40 DNA in human tumours, especially mesotheliomas, brain tumours and osteosarcomas; and DNA sequence analyses have ruled out the possibility that the viral DNA in tumours was due to laboratory contamination or that the virus had been misidentified. However, additional studies are necessary to prove that SV40 is the cause of certain human cancers. A recently published review article evaluated the status of the field and received much media attention. The public response emphasized that there is great interest in the possibility of health risks today from vaccinations received in the past.

  14. Progress in Aluminum Electrolysis Control and Future Direction for Smart Aluminum Electrolysis Plant

    Science.gov (United States)

    Zhang, Hongliang; Li, Tianshuang; Li, Jie; Yang, Shuai; Zou, Zhong

    2017-02-01

    The industrial aluminum reduction cell is an electrochemistry reactor that operates under high temperatures and highly corrosive conditions. However, these conditions have restricted the measurement of key control parameters, making the control of aluminum reduction cells a difficult problem in the industry. Because aluminum electrolysis control systems have a significant economic influence, substantial research has been conducted on control algorithms, control systems and information systems for aluminum reduction cells. This article first summarizes the development of control systems and then focuses on the progress made since 2000, including alumina concentration control, temperature control and electrolyte molecular ratio control, fault diagnosis, cell condition prediction and control system expansion. Based on these studies, the concept of a smart aluminum electrolysis plant is proposed. The frame construction, key problems and current progress are introduced. Finally, several future directions are discussed.

  15. 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

  16. The Pennsylvania State University Light Water Ultra-Safe Plant Concept: 3rd quarter progress report

    International Nuclear Information System (INIS)

    Klevans, E.

    1987-01-01

    Progress in the Ultra Safe study has substantially increased since the last report. The search for pressurizing pump turbine component information is now complete and a final plant layout for detailed evaluation has been chosen. Significant results for the normal operation performance of the Ultra Safe pressurizing technique are included. The plan of attack for the evaluation of the Ultra Safe shutdown scenario and natural circulation capability is discussed. This process is expected to be the next key area for analysis. The reactor design is complete including a change to alleviate the need for a soluble boron system. Material on the reactor building layout is also provided

  17. High occurrence of hepatitis E virus in samples from wastewater treatment plants in Switzerland and comparison with other enteric viruses.

    Science.gov (United States)

    Masclaux, Frédéric G; Hotz, Philipp; Friedli, Drita; Savova-Bianchi, Dessislava; Oppliger, Anne

    2013-09-15

    Hepatitis E virus (HEV) is responsible for many enterically transmitted viral hepatitides around the world. It is currently one of the waterborne diseases of global concern. In industrialized countries, HEV appears to be more common than previously thought, even if it is rarely virulent. In Switzerland, seroprevalence studies revealed that HEV is endemic, but no information was available on its environmental spread. The aim of this study was to investigate -using qPCR- the occurrence and concentration of HEV and three other viruses (norovirus genogroup II, human adenovirus-40 and porcine adenovirus) in influents and effluents of 31 wastewater treatment plants (WWTPs) in Switzerland. Low concentrations of HEV were detected in 40 out of 124 WWTP influent samples, showing that HEV is commonly present in this region. The frequency of HEV occurrence was higher in summer than in winter. No HEV was detected in WWTP effluent samples, which indicates a low risk of environmental contamination. HEV occurrence and concentrations were lower than those of norovirus and adenovirus. The autochthonous HEV genotype 3 was found in all positive samples, but a strain of the non-endemic and highly pathogenic HEV genotype I was isolated in one sample, highlighting the possibility of environmental circulation of this genotype. A porcine fecal marker (porcine adenovirus) was not detected in HEV positive samples, indicating that swine are not the direct source of HEV present in wastewater. Further investigations will be necessary to determine the reservoirs and the routes of dissemination of HEV. Copyright © 2013 Elsevier Ltd. All rights reserved.

  18. Clustering and cellular distribution characteristics of virus particles of Tomato spotted wilt virus and Tomato zonate spot virus in different plant hosts.

    Science.gov (United States)

    Zhang, Zhongkai; Zheng, Kuanyu; Dong, Jiahong; Fang, Qi; Hong, Jian; Wang, Xifeng

    2016-01-19

    Tomato spotted wilt virus (TSWV) and Tomato zonate spot virus (TZSV) are the two dominant species of thrip-transmitted tospoviruses, cause significant losses in crop yield in Yunnan and its neighboring provinces in China. TSWV and TZSV belong to different serogroup of tospoviruses but induce similar symptoms in the same host plant species, which makes diagnostic difficult. We used different electron microscopy preparing methods to investigate clustering and cellular distribution of TSWV and TZSV in the host plant species. Negative staining of samples infected with TSWV and TZSV revealed that particles usually clustered in the vesicles, including single particle (SP), double particles clustering (DPC), triple particles clustering (TPC). In the immunogold labeling negative staining against proteins of TZSV, the antibodies against Gn protein were stained more strongly than the N protein. Ultrathin section and high pressure freeze (HPF)-electron microscopy preparations revealed that TSWV particles were distributed in the cisternae of endoplasmic reticulum (ER), filamentous inclusions (FI) and Golgi bodies in the mesophyll cells. The TSWV particles clustered as multiple particles clustering (MPC) and distributed in globular viroplasm or cisternae of ER in the top leaf cell. TZSV particles were distributed more abundantly in the swollen membrane of ER in the mesophyll cell than those in the phloem parenchyma cells and were not observed in the top leaf cell. However, TZSV virions were mainly present as single particle in the cytoplasm, with few clustering as MPC. In this study, we identified TSWV and TZSV particles had the distinct cellular distribution patterns in the cytoplasm from different tissues and host plants. This is the first report of specific clustering characteristics of tospoviruses particles as well as the cellular distribution of TSWV particles in the FI and globular viroplasm where as TZSV particles inside the membrane of ER. These results indicated that

  19. Progression of rabbit haemorrhagic disease virus 2 upon vaccination in an industrial rabbitry: a laboratorial approach

    Directory of Open Access Journals (Sweden)

    C.L. Carvalho

    2017-03-01

    Full Text Available Rabbit haemorrhagic disease virus 2 (RHDV2 emerged recently in several European countries, leading to extensive economic losses in the industry. In response to this new infection, specific inactivated vaccines were developed in Europe and full and rapid setup of protective immunity induced by vaccination was reported. However, data on the efficacy of these vaccines in an ongoing-infection scenario is unavailable. In this study we investigated an infected RHDV2 indoor industrial meat rabbitry, where fatalities continued to occur after the implementation of the RHDV2 vaccination, introduced to control the disease. The aim of this study was to understand if these mortalities were RHDV2-related, to discover if the dead animals showed any common features such as age or time distance from vaccination, and to identify the source of the outbreak. Anatomo-pathological analysis of vaccinated animals with the virus showed lesions compatible with systemic haemorrhagic disease and RHDV2-RNA was detected in 85.7% of the animals tested. Sequencing of the vp60 gene amplified from liver samples led to the recognition of RHDV2 field strains demonstrating that after the implementation of vaccination, RHDV2 continued to circulate in the premises and to cause sporadic deaths. A nearby, semi-intensive, RHDV2 infected farm belonging to the same owner was identified as the most probable source of the virus. The main risk factors for virus introduction in these two industries were identified. Despite the virus being able to infect a few of the vaccinated rabbits, the significant decrease in mortality rate observed in vaccinated adult rabbits clearly reflects the efficacy of the vaccination. Nonetheless, the time taken to control the infection also highlights the importance of RHDV2 vaccination prior to the first contact with the virus, highly recommendable in endemic areas, to mitigate the infection’s impact on the industry.

  20. 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

    Mimicking and exploiting virus properties and physicochemical and physical characteristics holds promise to provide solutions to some of the world's most pressing challenges. The sheer range and types of viruses coupled with their intriguing properties potentially give endless opportunities for applications in virus-based technologies. Viruses have the ability to self- assemble into particles with discrete shape and size, specificity of symmetry, polyvalence, and stable properties under a wide range of temperature and pH conditions. Not surprisingly, with such a remarkable range of properties, viruses are proposed for use in biomaterials, vaccines, electronic materials, chemical tools, and molecular electronic containers. In order to utilize viruses in nanotechnology, they must be modified from their natural forms to impart new functions. This challenging process can be performed through several mechanisms including genetic modification of the viral genome and chemically attaching foreign or desired molecules to the virus particle reactive groups. The ability to modify a virus primarily depends upon the physiochemical and physical properties of the virus. In addition, the genetic or physiochemical modifications need to be performed without adversely affecting the virus native structure and virus function. Maize rayado fino virus (MRFV) coat proteins self-assemble in Escherichia coli producing stable and empty VLPs that are stabilized by protein-protein interactions and that can be used in virus-based technologies applications. VLPs produced in tobacco plants were examined as a scaffold on which a variety of peptides can be covalently displayed. Here, we describe the steps to 1) determine which of the solvent-accessible cysteines in a virus capsid are available for modification, and 2) bioconjugate peptides to the modified capsids. By using native or mutationally-inserted amino acid residues and standard coupling technologies, a wide variety of materials have been

  1. Progression of Pathogenic Events in Cynomolgus Macaques Infected with Variola Virus

    Science.gov (United States)

    2011-10-01

    times, centrifuged, and clarified supernatant was removed for extraction . DNA was extracted from ethylenediaminetetraacetic acid (EDTA) blood to analyze...virus load. All samples were lysed and extracted using the QIAamp Mini Kit (QIAGEN, Valencia, CA) according to the manufacturer’s instructions. qrt-PCR...mesenteric lymph nodes, salivary gland, testis or ovary, liver, gallbladder , spleen, adrenal gland, left and right kidneys, lung, heart, tongue

  2. Emergence of CD134 cysteine-rich domain 2 (CRD2)-independent strains of feline immunodeficiency virus (FIV) is associated with disease progression in naturally infected cats.

    Science.gov (United States)

    Bęczkowski, Paweł M; Techakriengkrai, Navapon; Logan, Nicola; McMonagle, Elizabeth; Litster, Annette; Willett, Brian J; Hosie, Margaret J

    2014-11-28

    Feline immunodeficiency virus (FIV) infection is mediated by sequential interactions with CD134 and CXCR4. Field strains of virus vary in their dependence on cysteine-rich domain 2 (CRD2) of CD134 for infection. Here, we analyse the receptor usage of viral variants in the blood of 39 naturally infected cats, revealing that CRD2-dependent viral variants dominate in early infection, evolving towards CRD2-independence with disease progression. These findings are consistent with a shift in CRD2 of CD134 usage with disease progression.

  3. RNA Interference towards the Potato Psyllid, Bactericera cockerelli, Is Induced in Plants Infected with Recombinant Tobacco mosaic virus (TMV)

    Science.gov (United States)

    Wuriyanghan, Hada; Falk, Bryce W.

    2013-01-01

    The potato/tomato psyllid, Bactericera cockerelli (B. cockerelli), is an important plant pest and the vector of the phloem-limited bacterium Candidatus Liberibacter psyllaurous (solanacearum), which is associated with the zebra chip disease of potatoes. Previously, we reported induction of RNA interference effects in B. cockerelli via in vitro-prepared dsRNA/siRNAs after intrathoracic injection, and after feeding of artificial diets containing these effector RNAs. In order to deliver RNAi effectors via plant hosts and to rapidly identify effective target sequences in plant-feeding B. cockerelli, here we developed a plant virus vector-based in planta system for evaluating candidate sequences. We show that recombinant Tobacco mosaic virus (TMV) containing B. cockerelli sequences can efficiently infect and generate small interfering RNAs in tomato (Solanum lycopersicum), tomatillo (Physalis philadelphica) and tobacco (Nicotiana tabacum) plants, and more importantly delivery of interfering sequences via TMV induces RNAi effects, as measured by actin and V-ATPase mRNA reductions, in B. cockerelli feeding on these plants. RNAi effects were primarily detected in the B. cockerelli guts. In contrast to our results with TMV, recombinant Potato virus X (PVX) and Tobacco rattle virus (TRV) did not give robust infections in all plants and did not induce detectable RNAi effects in B. cockerelli. The greatest RNA interference effects were observed when B. cockerelli nymphs were allowed to feed on leaf discs collected from inoculated or lower expanded leaves from corresponding TMV-infected plants. Tomatillo plants infected with recombinant TMV containing B. cockerelli actin or V-ATPase sequences also showed phenotypic effects resulting in decreased B. cockerelli progeny production as compared to plants infected by recombinant TMV containing GFP. These results showed that RNAi effects can be achieved in plants against the phloem feeder, B. cockerelli, and the TMV-plant system will

  4. One System Integrated Project Team Progress in Coordinating Hanford Tank Farms and the Waste Treatment Plant

    International Nuclear Information System (INIS)

    Skwarek, Raymond J.; Harp, Ben J.; Duncan, Garth M.

    2013-01-01

    The One System Integrated Project Team (IPT) was formed at the Hanford Site in late 2011 as a way to improve coordination and itegration between the Hanford Tank Waste Treatment and Immobilization Plant (WTP) and the Tank Operations Contractor (TOC) on interfaces between the two projects, and to eliminate duplication and exploit opportunities for synergy. The IPT is composed of jointly staffed groups that work on technical issues of mutal interest, front-end design and project definition, nuclear safety, plant engineering system integration, commissioning, planning and scheduling, and environmental, safety, health and quality (ESH&Q) areas. In the past year important progress has been made in a number of areas as the organization has matured and additional opportunities have been identified. Areas covered in this paper include: Support for development of the Office of Envirnmental Management (EM) framework document to progress the Office of River Protection's (ORP) River Protection Project (RPP) mission; Stewardship of the RPP flowsheet; Collaboration with Savannah River Site (SRS), Savannah River National Laboratory (SRNL), and Pacific Northwest National Laboratory (PNNL); Operations programs integration; and, Further development of the waste acceptance criteria

  5. Plant hormone cytokinins control cell cycle progression and plastid replication in apicomplexan parasites.

    Science.gov (United States)

    Andrabi, Syed Bilal Ahmad; Tahara, Michiru; Matsubara, Ryuma; Toyama, Tomoko; Aonuma, Hiroka; Sakakibara, Hitoshi; Suematsu, Makoto; Tanabe, Kazuyuki; Nozaki, Tomoyoshi; Nagamune, Kisaburo

    2018-02-01

    Cytokinins are plant hormones that are involved in regulation of cell proliferation, cell cycle progression, and cell and plastid development. Here, we show that the apicomplexan parasites Toxoplasma gondii and Plasmodium berghei, an opportunistic human pathogen and a rodent malaria agent, respectively, produce cytokinins via a biosynthetic pathway similar to that in plants. Cytokinins regulate the growth and cell cycle progression of T. gondii by mediating expression of the cyclin gene TgCYC4. A natural form of cytokinin, trans-zeatin (t-zeatin), upregulated expression of this cyclin, while a synthetic cytokinin, thidiazuron, downregulated its expression. Immunofluorescence microscopy and quantitative PCR analysis showed that t-zeatin increased the genome-copy number of apicoplast, which are non-photosynthetic plastid, in the parasite, while thidiazuron led to their disappearance. Thidiazuron inhibited growth of T. gondii and Plasmodium falciparum, a human malaria parasite, suggesting that thidiazuron has therapeutic potential as an inhibitor of apicomplexan parasites. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

  6. IAEA Operational Safety Team (OSART) Reviews Progress at Fessenheim Nuclear Power Plant, France

    International Nuclear Information System (INIS)

    2011-01-01

    Full text: An international team of nuclear installation safety experts, led by the International Atomic Energy Agency (IAEA), has evaluated the French Nuclear Power Plant (NPP) at Fessenheim to assess how the facility has followed up on an Operational Safety Review Team (OSART) mission undertaken in 2009. The IAEA assembled a team of experts at the request of the Government of France to conduct the mission. Follow-up missions are standard components of the OSART programme and are conducted 18-24 months after the initial OSART mission. Under the leadership of the IAEA's Division of Nuclear Installation Safety, the team performed its review from 7 to 11 February 2011. The team assessed how the Fessenheim NPP has addressed the recommendations and suggestions made during the 2009 OSART mission. The team was made up of experts from Slovakia, Switzerland and the IAEA. The review covered the areas of Management, Organization and Administration; Training and Qualifications; Operations; Maintenance; Technical Support; Operating Experience; Radiation Protection; Chemistry and Emergency Planning and Preparedness. The conclusions of the follow-up review are based on the IAEA's Safety Standards and proven good international practices. There were 21 issues raised by the 2009 mission. During the follow-up mission, the team assessed that six issues had been resolved, thirteen had made satisfactory progress to date and two had made insufficient progress to date. 'Resolved' describes action plans for improvement that have been fully implemented; 'satisfactory progress to date' describes action plans that have been developed but are not yet fully implemented; and 'insufficient progress to date' describes situations where additional consideration or strengthening of improvement plans is necessary. Examples of issues falling into different resolution categories include: The plant has resolved the suggestion to establish a process to review initial training materials on a regular basis

  7. The roles of membranes and associated cytoskeleton in plant virus replication and cell-to-cell movement.

    Science.gov (United States)

    Pitzalis, Nicolas; Heinlein, Manfred

    2017-12-18

    The infection of plants by viruses depends on cellular mechanisms that support the replication of the viral genomes, and the cell-to-cell and systemic movement of the virus via plasmodesmata (PD) and the connected phloem. While the propagation of some viruses requires the conventional endoplasmic reticulum (ER)-Golgi pathway, others replicate and spread between cells in association with the ER and are independent of this pathway. Using selected viruses as examples, this review re-examines the involvement of membranes and the cytoskeleton during virus infection and proposes potential roles of class VIII myosins and membrane-tethering proteins in controlling viral functions at specific ER subdomains, such as cortical microtubule-associated ER sites, ER-plasma membrane contact sites, and PD. © The Author(s) 2017. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  8. Environment, safety and Health Progress Assessment of the Rocky Flats Plant

    International Nuclear Information System (INIS)

    1993-05-01

    This report documents the result of the US Department of Energy's (DOE) Environment, Safety and Health (ES ampersand H) Progress Assessment of the DOE Rocky Flats Plant (RFP) in Golden, Colorado. The assessment, which was conducted during the period of May 17 through May 28, 1993, included a selective review of the ES ampersand H management systems and programs of the responsible DOE Headquarters Program Offices (Defense Programs (DP) and Environmental Restoration and Waste Management (EM)), the DOE Rocky Flats Office (RFO), and the site contractor, EG ampersand G Rocky Flats, Inc. (EG ampersand G). Despite the near constant state of flux under which RFP has been required to operate, the Progress Assessment Team has concluded that significant progress has been made in correcting the deficiencies identified in the 1989 Assessment and in responding responsibly to regulations, and DOE directives and guidance that have been issued since that time. The Team concluded that the improvements have been concentrated in the activities associated with plutonium facilities and in regulatory driven programs. Much remains to be done with respect to implementing on a sitewide basis those management systems that anchor an organization's pursuit of continuous ES ampersand H improvement. Furthermore the Team concluded that the pace of improvement has been constrained by a combination of factors that have limited the site's ability to manage change in the pursuit of sitewide ES ampersand H excellence

  9. Structural and Functional Diversity of Plant Virus 3'-Cap-Independent Translation Enhancers (3'-CITEs).

    Science.gov (United States)

    Truniger, Verónica; Miras, Manuel; Aranda, Miguel A

    2017-01-01

    Most of the positive-strand RNA plant viruses lack the 5'-cap and/or the poly(A)-tail that act synergistically to stimulate canonical translation of cellular mRNAs. However, they have RNA elements in the 5'- or 3'-untranslated regions of their RNAs that are required for their cap-independent translation. Cap-independent translation enhancers (CITEs) have been identified in the genomic 3'-end of viruses belonging to the family Tombusviridae and the genus Luteovirus . Seven classes of 3'-CITEs have been described to date based on their different RNA structures. They generally control the efficient formation of the translation initiation complex by varying mechanisms. Some 3'-CITEs bind eukaryotic translation initiation factors, others ribosomal subunits, bridging these to the 5'-end by different mechanisms, often long-distance RNA-RNA interactions. As previously proposed and recently found in one case in nature, 3'-CITEs are functionally independent elements that are transferable through recombination between viral genomes, leading to potential advantages for virus multiplication. In this review, the knowledge on 3'-CITEs and their functioning is updated. We also suggest that there is local structural conservation in the regions interacting with eIF4E of 3'-CITEs belonging to different classes.

  10. An antiviral RISC isolated from Tobacco rattle virus-infected plants.

    Science.gov (United States)

    Ciomperlik, Jessica J; Omarov, Rustem T; Scholthof, Herman B

    2011-03-30

    The RNAi model predicts that during antiviral defense a RNA-induced silencing complex (RISC) is programmed with viral short-interfering RNAs (siRNAs) to target the cognate viral RNA for degradation. We show that infection of Nicotiana benthamiana with Tobacco rattle virus (TRV) activates an antiviral nuclease that specifically cleaves TRV RNA in vitro. In agreement with known RISC properties, the nuclease activity was inhibited by NaCl and EDTA and stimulated by divalent metal cations; a novel property was its preferential targeting of elongated RNA molecules. Intriguingly, the specificity of the TRV RISC could be reprogrammed by exogenous addition of RNA (containing siRNAs) from plants infected with an unrelated virus, resulting in a newly acquired ability of RISC to target this heterologous genome in vitro. Evidently the virus-specific nuclease complex from N. benthamiana represents a genuine RISC that functions as a readily employable and reprogrammable antiviral defense unit. Copyright © 2011 Elsevier Inc. All rights reserved.

  11. Progression of rabbit haemorrhagic disease virus 2 upon vaccination in an industrial rabbitry: a laboratorial approach

    OpenAIRE

    C.L. Carvalho; E.L. Duarte; J.M. Monteiro; C. Afonso; J. Pacheco; P. Carvalho; P. Mendonça; A. Botelho; T. Albuquerque; P. Themudo; M. Fevereiro; A.M. Henriques; S.S. Santos Barros; M. Dias Duarte

    2017-01-01

    Rabbit haemorrhagic disease virus 2 (RHDV2) emerged recently in several European countries, leading to extensive economic losses in the industry. In response to this new infection, specific inactivated vaccines were developed in Europe and full and rapid setup of protective immunity induced by vaccination was reported. However, data on the efficacy of these vaccines in an ongoing-infection scenario is unavailable. In this study we investigated an infected RHDV2 indoor industrial meat rabbitry...

  12. A heterologous prime-boosting strategy with replicating Vaccinia virus vectors and plant-produced HIV-1 Gag/dgp41 virus-like particles

    Energy Technology Data Exchange (ETDEWEB)

    Meador, Lydia R. [Ira A. Fulton School of Engineering, Arizona State University, Tempe, AZ (United States); Center for Infectious Diseases and Vaccinology, The Biodesign Institute, Arizona State University, Tempe, AZ (United States); Kessans, Sarah A. [Center for Infectious Diseases and Vaccinology, The Biodesign Institute, Arizona State University, Tempe, AZ (United States); School of Life Sciences, Arizona State University, Tempe, AZ (United States); Kilbourne, Jacquelyn; Kibler, Karen V. [Center for Infectious Diseases and Vaccinology, The Biodesign Institute, Arizona State University, Tempe, AZ (United States); Pantaleo, Giuseppe [Division of Immunology and Allergy, Centre Hospitalier Universitaire Vaudois, University of Lausanne, Lausanne (Switzerland); Swiss Vaccine Research Institute, Lausanne (Switzerland); Roderiguez, Mariano Esteban [Department of Molecular and Cellular Biology, Centro Nacional de Biotecnologia – CSIC, Madrid (Spain); Blattman, Joseph N. [Center for Infectious Diseases and Vaccinology, The Biodesign Institute, Arizona State University, Tempe, AZ (United States); School of Life Sciences, Arizona State University, Tempe, AZ (United States); Jacobs, Bertram L., E-mail: bjacobs@asu.edu [Center for Infectious Diseases and Vaccinology, The Biodesign Institute, Arizona State University, Tempe, AZ (United States); School of Life Sciences, Arizona State University, Tempe, AZ (United States); Mor, Tsafrir S., E-mail: tsafrir.mor@asu.edu [Center for Infectious Diseases and Vaccinology, The Biodesign Institute, Arizona State University, Tempe, AZ (United States); School of Life Sciences, Arizona State University, Tempe, AZ (United States)

    2017-07-15

    Showing modest efficacy, the RV144 HIV-1 vaccine clinical trial utilized a non-replicating canarypox viral vector and a soluble gp120 protein boost. Here we built upon the RV144 strategy by developing a novel combination of a replicating, but highly-attenuated Vaccinia virus vector, NYVAC-KC, and plant-produced HIV-1 virus-like particles (VLPs). Both components contained the full-length Gag and a membrane anchored truncated gp41 presenting the membrane proximal external region with its conserved broadly neutralizing epitopes in the pre-fusion conformation. We tested different prime/boost combinations of these components in mice and showed that the group primed with NYVAC-KC and boosted with both the viral vectors and plant-produced VLPs have the most robust Gag-specific CD8 T cell responses, at 12.7% of CD8 T cells expressing IFN-γ in response to stimulation with five Gag epitopes. The same immunization group elicited the best systemic and mucosal antibody responses to Gag and dgp41 with a bias towards IgG1. - Highlights: • We devised a prime/boost anti HIV-1 vaccination strategy modeled after RV144. • We used plant-derived virus-like particles (VLPs) consisting of Gag and dgp41. • We used attenuated, replicating vaccinia virus vectors expressing the same antigens. • The immunogens elicited strong cellular and humoral immune responses.

  13. Zika virus infection, transmission, associated neurological disorders and birth abnormalities: A review of progress in research, priorities and knowledge gaps

    Directory of Open Access Journals (Sweden)

    Yitades Gebre

    2016-10-01

    Full Text Available On February 1, 2016, the World Health Organization declared that the cluster of microcephaly cases and other neurological disorders constitute public health emergency of international concern. Furthermore, few studies demonstrated that there was an increased evidence of causal relationship of Zika virus (ZIKAV infection and microcephaly, birth abnormalities and neurological disorders such as Guillain–Barré syndrome. ZIKAV transmission occurs mainly by the bite of infected mosquitos (Aedes species, but there are also reports that infections could occur via the placenta, breast milk, saliva, blood transfusion and sex. This article reviews the global efforts, progress in scientific research to understand the pathogenesis of ZIKAV infection & disease, clinical presentations, congenital transmission and autoimmune neurological disorders. The paper further explores the knowledge gaps, future priority research agenda for strategic response including vector control and prevention. We conducted a systematic literature review to synthesise available evidence on ZIKAV infection and its vector and host interaction from electronic databases.

  14. Zika virus infection, transmission, associated neurological disorders and birth abnormalities: A review of progress in research, priorities and knowledge gaps

    Institute of Scientific and Technical Information of China (English)

    Yitades Gebre; Nikkiah Forbes; Teshome Gebre

    2016-01-01

    On February 1, 2016, the World Health Organization declared that the cluster of microcephaly cases and other neurological disorders constitute public health emergency of international concern. Furthermore, few studies demonstrated that there was an increased evidence of causal relationship of Zika virus(ZIKAV) infection and microcephaly, birth abnormalities and neurological disorders such as Guillain–Barre′ syndrome.ZIKAV transmission occurs mainly by the bite of infected mosquitos(Aedes species), but there are also reports that infections could occur via the placenta, breast milk, saliva,blood transfusion and sex. This article reviews the global efforts, progress in scientific research to understand the pathogenesis of ZIKAV infection & disease, clinical presentations, congenital transmission and autoimmune neurological disorders. The paper further explores the knowledge gaps, future priority research agenda for strategic response including vector control and prevention. We conducted a systematic literature review to synthesise available evidence on ZIKAV infection and its vector and host interaction from electronic databases.

  15. Infection of non-host model plant species with the narrow-host-range Cacao swollen shoot virus.

    Science.gov (United States)

    Friscina, Arianna; Chiappetta, Laura; Jacquemond, Mireille; Tepfer, Mark

    2017-02-01

    Cacao swollen shoot virus (CSSV) is a major pathogen of cacao (Theobroma cacao) in Africa, and long-standing efforts to limit its spread by the culling of infected trees have had very limited success. CSSV is a particularly difficult virus to study, as it has a very narrow host range, limited to several tropical tree species. Furthermore, the virus is not mechanically transmissible, and its insect vector can only be used with difficulty. Thus, the only efficient means to infect cacao plants that have been experimentally described so far are by particle bombardment or the agroinoculation of cacao plants with an infectious clone. We have genetically transformed three non-host species with an infectious form of the CSSV genome: two experimental hosts widely used in plant virology (Nicotiana tabacum and N. benthamiana) and the model species Arabidopsis thaliana. In transformed plants of all three species, the CSSV genome was able to replicate, and, in tobacco, CSSV particles could be observed by immunosorbent electron microscopy, demonstrating that the complete virus cycle could be completed in a non-host plant. These results will greatly facilitate the preliminary testing of CSSV control strategies using plants that are easy to raise and to transform genetically. © 2016 BSPP AND JOHN WILEY & SONS LTD.

  16. Progressive erosion of genetic and epigenetic variation in callus-derived cocoa (Theobroma cacao) plants.

    Science.gov (United States)

    Rodríguez López, Carlos M; Wetten, Andrew C; Wilkinson, Michael J

    2010-06-01

    *Relatively little is known about the timing of genetic and epigenetic forms of somaclonal variation arising from callus growth. We surveyed for both types of change in cocoa (Theobroma cacao) plants regenerated from calli of various ages, and also between tissues from the source trees. *For genetic change, we used 15 single sequence repeat (SSR) markers from four source trees and from 233 regenerated plants. For epigenetic change, we used 386 methylation-sensitive amplified polymorphism (MSAP) markers on leaf and explant (staminode) DNA from two source trees and on leaf DNA from 114 regenerants. *Genetic variation within source trees was limited to one slippage mutation in one leaf. Regenerants were far more variable, with 35% exhibiting at least one mutation. Genetic variation initially accumulated with culture age but subsequently declined. MSAP (epigenetic) profiles diverged between leaf and staminode samples from source trees. Multivariate analysis revealed that leaves from regenerants occupied intermediate eigenspace between leaves and staminodes of source plants but became progressively more similar to source tree leaves with culture age. *Statistical analysis confirmed this rather counterintuitive finding that leaves of 'late regenerants' exhibited significantly less genetic and epigenetic divergence from source leaves than those exposed to short periods of callus growth.

  17. Progress and challenges of engineering a biophysical CO2-concentrating mechanism into higher plants.

    Science.gov (United States)

    Rae, Benjamin D; Long, Benedict M; Förster, Britta; Nguyen, Nghiem D; Velanis, Christos N; Atkinson, Nicky; Hee, Wei Yih; Mukherjee, Bratati; Price, G Dean; McCormick, Alistair J

    2017-06-01

    Growth and productivity in important crop plants is limited by the inefficiencies of the C3 photosynthetic pathway. Introducing CO2-concentrating mechanisms (CCMs) into C3 plants could overcome these limitations and lead to increased yields. Many unicellular microautotrophs, such as cyanobacteria and green algae, possess highly efficient biophysical CCMs that increase CO2 concentrations around the primary carboxylase enzyme, Rubisco, to enhance CO2 assimilation rates. Algal and cyanobacterial CCMs utilize distinct molecular components, but share several functional commonalities. Here we outline the recent progress and current challenges of engineering biophysical CCMs into C3 plants. We review the predicted requirements for a functional biophysical CCM based on current knowledge of cyanobacterial and algal CCMs, the molecular engineering tools and research pipelines required to translate our theoretical knowledge into practice, and the current challenges to achieving these goals. © The Author 2017. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  18. 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.

  19. Study of Containment Vent Strategies During Severe Accident Progression for the CANDU6 Plant

    Energy Technology Data Exchange (ETDEWEB)

    Jin, Youngho; Ahn, K. I. [KAERI, Daejeon (Korea, Republic of)

    2015-05-15

    In March, 2011, Fukushima daichi nuclear power plants experienced a long term station blackout. Severe core damage occurred and a large amount of radioactive materials are released outside of the plants. After this terrible accident Nuclear Safety and Security Commission (NSSC) enforced to increase nuclear safety for all operating plants in Korea. To increase plant safety, both hardware reinforcement and software improvement are encouraged. Hardware reinforcement includes the preparation of the external water injection paths to the RCS and the spent fuel pool, a filtered containment venting system (CFVS), and AC power generating truck. Software improvement includes the increase of the effectiveness of the severe accident management guidance (SAMG) and plant staff training. To comply with NSSC's request, Wolsong Unit 1 has fulfilled the hardware reinforcement including the installation of a CFVS and started the extension of a SAMG to the low power and shutdown operation mode. Current SAMG deals accident occurred during full power operation only. The CFVS is designed to open and to close isolation valves manually. It does not require AC power. The operation of the CFVS prevents the reactor containment building failure due to the over-pressurization but it may release radioactive materials out of the reactor containment building. This paper discusses the radiological source terms for the containment vent strategy during severe accident progression which occurred during shutdown operation mode. This work is a part of the development of shutdown SAMG.. The CFVS is an effective means to control the containment pressure when the local air coolers are unavailable. Radioactive materials may release through the CFVS, but their amounts are reduced significantly. The alternative means, i.e., containment vent through the ventilation system which does not have an effective filter, is not a good choice to control the containment condition. It can maintain the containment

  20. Tracking the potyviral P1 protein in Nicotiana benthamiana plants during plum pox virus infection.

    Science.gov (United States)

    Vozárová, Z; Glasa, M; Šubr, Z W

    The P1 protein is derived from the N terminus of potyvirus-coded polyprotein. In addition to the proteolytic activity essential for its maturation, it probably participates in suppression of host defense and/or in virus replication. Clear validation of the P1 in vivo function(s), however, is not yet available. We applied an infectious cDNA clone of plum pox virus (PPV), where the P1 was N-fused with a hexahistidine tag, to trace this protein in Nicotiana benthamiana plants during the PPV infection. Immunoblot analysis with the anti-his antibody showed a diffuse band corresponding to the molecular weight about 70-80 kDa (about twice larger than expected) in the root samples from early stage of infection. This signal culminated on the sixth day post inoculation, later it rapidly disappeared. Sample denaturation by boiling in SDS before centrifugal clarification was essential, indicating strong affinity of P1-his to some plant compound sedimenting with the tissue and cell debris.

  1. Investigating Gene Function in Cereal Rust Fungi by Plant-Mediated Virus-Induced Gene Silencing.

    Science.gov (United States)

    Panwar, Vinay; Bakkeren, Guus

    2017-01-01

    Cereal rust fungi are destructive pathogens, threatening grain production worldwide. Targeted breeding for resistance utilizing host resistance genes has been effective. However, breakdown of resistance occurs frequently and continued efforts are needed to understand how these fungi overcome resistance and to expand the range of available resistance genes. Whole genome sequencing, transcriptomic and proteomic studies followed by genome-wide computational and comparative analyses have identified large repertoire of genes in rust fungi among which are candidates predicted to code for pathogenicity and virulence factors. Some of these genes represent defence triggering avirulence effectors. However, functions of most genes still needs to be assessed to understand the biology of these obligate biotrophic pathogens. Since genetic manipulations such as gene deletion and genetic transformation are not yet feasible in rust fungi, performing functional gene studies is challenging. Recently, Host-induced gene silencing (HIGS) has emerged as a useful tool to characterize gene function in rust fungi while infecting and growing in host plants. We utilized Barley stripe mosaic virus-mediated virus induced gene silencing (BSMV-VIGS) to induce HIGS of candidate rust fungal genes in the wheat host to determine their role in plant-fungal interactions. Here, we describe the methods for using BSMV-VIGS in wheat for functional genomics study in cereal rust fungi.

  2. Progression of pathogenic events in cynomolgus macaques infected with variola virus.

    Directory of Open Access Journals (Sweden)

    Victoria Wahl-Jensen

    Full Text Available Smallpox, caused by variola virus (VARV, is a devastating human disease that affected millions worldwide until the virus was eradicated in the 1970 s. Subsequent cessation of vaccination has resulted in an immunologically naive human population that would be at risk should VARV be used as an agent of bioterrorism. The development of antivirals and improved vaccines to counter this threat would be facilitated by the development of animal models using authentic VARV. Towards this end, cynomolgus macaques were identified as adequate hosts for VARV, developing ordinary or hemorrhagic smallpox in a dose-dependent fashion. To further refine this model, we performed a serial sampling study on macaques exposed to doses of VARV strain Harper calibrated to induce ordinary or hemorrhagic disease. Several key differences were noted between these models. In the ordinary smallpox model, lymphoid and myeloid hyperplasias were consistently found whereas lymphocytolysis and hematopoietic necrosis developed in hemorrhagic smallpox. Viral antigen accumulation, as assessed immunohistochemically, was mild and transient in the ordinary smallpox model. In contrast, in the hemorrhagic model antigen distribution was widespread and included tissues and cells not involved in the ordinary model. Hemorrhagic smallpox developed only in the presence of secondary bacterial infections - an observation also commonly noted in historical reports of human smallpox. Together, our results support the macaque model as an excellent surrogate for human smallpox in terms of disease onset, acute disease course, and gross and histopathological lesions.

  3. Immunogenicity of plant-produced African horse sickness virus-like particles: implications for a novel vaccine.

    Science.gov (United States)

    Dennis, Susan J; Meyers, Ann E; Guthrie, Alan J; Hitzeroth, Inga I; Rybicki, Edward P

    2018-02-01

    African horse sickness (AHS) is a debilitating and often fatal viral disease affecting horses in much of Africa, caused by the dsRNA orbivirus African horse sickness virus (AHSV). Vaccination remains the single most effective weapon in combatting AHS, as there is no treatment for the disease apart from good animal husbandry. However, the only commercially available vaccine is a live-attenuated version of the virus (LAV). The threat of outbreaks of the disease outside its endemic region and the fact that the LAV is not licensed for use elsewhere in the world, have spurred attempts to develop an alternative safer, yet cost-effective recombinant vaccine. Here, we report the plant-based production of a virus-like particle (VLP) AHSV serotype five candidate vaccine by Agrobacterium tumefaciens-mediated transient expression of all four capsid proteins in Nicotiana benthamiana using the cowpea mosaic virus-based HyperTrans (CPMV-HT) and associated pEAQ plant expression vector system. The production process is fast and simple, scalable, economically viable, and most importantly, guinea pig antiserum raised against the vaccine was shown to neutralize live virus in cell-based assays. To our knowledge, this is the first report of AHSV VLPs produced in plants, which has important implications for the containment of, and fight against the spread of, this deadly disease. © 2017 The Authors. Plant Biotechnology Journal published by Society for Experimental Biology and The Association of Applied Biologists and John Wiley & Sons Ltd.

  4. Chimeric immune receptors (CIRs) specific to JC virus for immunotherapy in progressive multifocal leukoencephalopathy (PML)

    NARCIS (Netherlands)

    W. Yang; E.L. Beaudoin; L. Lu; R.A. Du Pasquier (Renaud); M.J. Kuroda; R.A. Willemsen (Ralph); I.J. Koralnik; R.P. Junghans

    2007-01-01

    textabstractProgressive multifocal leukoencephalopathy (PML) is a deadly brain disease caused by the polyomavirus JC (JCV). The aim of this study is to develop 'designer T cells' armed with anti-JCV TCR-based chimeric immune receptors (CIRs) by gene modification for PML immunotherapy. Two T cell

  5. IAEA Team Reviews Safety Progress at French Nuclear Power Plant 19-23 May 2014

    International Nuclear Information System (INIS)

    2014-01-01

    An international team of nuclear installation safety experts led by the International Atomic Energy Agency (IAEA) has evaluated the Gravelines Nuclear Power Plant (NPP) in France to assess how the station has followed up on an Operational Safety Review Team (OSART) mission undertaken in 2012. The IAEA assembled a team of experts at the request of the Government of France to conduct the follow-up OSART mission at Gravelines NPP from 19 to 23 May 2014. Follow-up missions are standard components of the OSART programme; they are typically conducted 15-24 months after the initial OSART mission. The IAEA mission in 2012 made a number of recommendations and suggestions for consideration by the Gravelines NPP operators. The station thoroughly analyzed the OSART recommendations and suggestions and developed corrective action plans. In 18 months, the Gravelines plant has achieved the level ''resolved;; or ''satisfactory progress'' in almost all of the recommendations and suggestions made by the OSART in November 2012. During the follow-up mission, the team assessed that the operators have resolved the issues in several areas, including: Undertaking initiatives to improve fire prevention; Reinforcing contamination control practices; and Enhancing capabilities to protect emergency workers in the event of a release of radioactivity. The team identified some issues which have achieved satisfactory progress toward resolution, but need further work, including: Further improvement of measures to preventing the ingress of items or chemicals into circuits and equipment; Comprehensive application of the corrective actions programme; and Reinforcement of the containment protection system in the event of an extremely adverse situation. The team identified the following issue as one which has made insufficient progress toward resolution and needs further work: Emergency response arrangements do not follow current IAEA safety standards recommending that the plant should have a person on

  6. M2 Macrophages Play Critical Roles in Progression of Inflammatory Liver Disease in Hepatitis C Virus Transgenic Mice.

    Science.gov (United States)

    Ohtsuki, Takahiro; Kimura, Kiminori; Tokunaga, Yuko; Tsukiyama-Kohara, Kyoko; Tateno, Chise; Hayashi, Yukiko; Hishima, Tsunekazu; Kohara, Michinori

    2016-01-01

    Macrophages in liver tissue are widely defined as important inflammatory cells in chronic viral hepatitis due to their proinflammatory activity. We reported previously that interleukin-6 (IL-6) and tumor necrosis factor alpha (TNF-α) play significant roles in causing chronic hepatitis in hepatitis C virus (HCV) transgenic mice (S. Sekiguchi et al., PLoS One 7:e51656, 2012, http://dx.doi.org/10.1371/journal.pone.0051656). In addition, we showed that recombinant vaccinia viruses expressing an HCV nonstructural protein (rVV-N25) could protect against the progression of chronic hepatitis by suppression of macrophage activation. Here, we focus on the role of macrophages in liver disease progression in HCV transgenic mice and examine characteristic features of macrophages following rVV-N25 treatment. The number of CD11b(+) F4/80(+) CD11c(-) CD206(+) (M2) macrophages in the liver of HCV transgenic mice was notably increased compared to that of age-matched control mice. These M2 macrophages in the liver produced elevated levels of IL-6 and TNF-α. rVV-N25 infection suppressed the number and activation of M2 macrophages in liver tissue. These results suggested that inflammatory cytokines produced by M2-like macrophages contribute to the induction of chronic liver inflammation in HCV transgenic mice. Moreover, the therapeutic effect of rVV-N25 might be induced by the suppression of the number and activation of hepatic macrophages. HCV causes persistent infections that can lead to chronic liver diseases, liver fibrosis, and hepatocellular carcinoma; the search for an HCV curative is the focus of ongoing research. Recently, effective anti-HCV drugs have been developed; however, vaccine development still is required for the prevention and therapy of infection by this virus. We demonstrate here that M2 macrophages are important for the pathogenesis of HCV-caused liver diseases and additionally show that M2 macrophages contribute to the therapeutic mechanism observed following r

  7. Antiviral activity of some Tunisian medicinal plants against Herpes simplex virus type 1.

    Science.gov (United States)

    Sassi, A Ben; Harzallah-Skhiri, F; Bourgougnon, N; Aouni, M

    2008-01-10

    Fifteen species of Tunisian traditional medicinal plants, belonging to 10 families, were selected for this study. They were Inula viscosa (L.) Ait and Reichardia tingitana (L.) Roth ssp. discolor (Pom.) Batt. (Asteraceae), Mesembryanthemum cristallinum L. and M. nodiflorum L. (Aizoaceae), Arthrocnemum indicum (Willd.) Moq., Atriplex inflata Muell., A. parvifolia Lowe var. ifiniensis (Caball) Maire, and Salicornia fruticosa L. (Chenopodiaceae), Cistus monspeliensis L. (Cistaceae), Juniperus phoenicea L. (Cupressaceae), Erica multiflora L. (Ericaceae), Frankenia pulverulenta L. (Frankeniaceae), Hypericum crispum L. (Hypericaceae), Plantago coronopus L. ssp. eu-coronopus Pilger var. vulgaris G.G. (Plantaginaceae) and Zygophyllum album L. (Zygophyllaceae). Fifty extracts prepared from those plants were screened in order to assay their antiviral activity against Herpes simplex virus type 1 (HSV-1), using neutral red incorporation. Extracts from eight plants among these 15 showed some degree of antiviral activity, while the methanolic extract of E. multiflora was highly active with EC(50) of 132.6 microg mL(-1). These results corroborate that medicinal plants from Tunisia can be a rich source of potential antiviral compounds.

  8. Internalization and dissemination of human norovirus and Tulane virus in fresh produce is plant dependent.

    Science.gov (United States)

    Yang, Zhihong; Chambers, Heather; DiCaprio, Erin; Gao, Gary; Li, Jianrong

    2018-02-01

    Human norovirus (NoV) is a leading cause of fresh produce associated outbreaks. Previous research indicates that the roots of growing leafy greens and berries internalize human NoV. However the effect of plant type and inoculum level on internalization rates has not been directly compared. In this study we compared the internalization and dissemination rates of human NoV and its surrogate, Tulane virus (TV) in green onion, radishes, and Romaine lettuce. We also evaluated the effect inoculum level and plant growth matrix on the rate of viral internalization. In the hydroponic growth system, we detected internalization and dissemination of human NoV RNA in green onions. In hydroponically growing green onions inoculated with high titer TV, we found higher rates of internalization and dissemination compared to green onions inoculated with low titer TV. In soil growth systems, no infectious TV was detected in either green onion or radishes. However, in Romaine lettuce plants grown in soil approximately 4 log 10  PFU/g was recovered from all tissues on day 14 p.i. Overall, we found that the type of plant, growth matrix, and the inoculum level influences the internalization and dissemination of human NoV and TV. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Psycho-immunology and HIV infection : biopsychosocial determinants of distress, immunological parameters, and disease progression in homosexual men infected with human immunodeficiency virus-1

    NARCIS (Netherlands)

    C.L. Mulder (Niels)

    1994-01-01

    textabstractSubjects who have tested positive for the presence of antibodies against Human Immunodeficiency Virus Type I (further abbreviated as HIV), have to live with a lifethreatening infection. At present, no definite medical cure is available that prevents progression of HIV infection.

  10. Progression of understanding for the role of Epstein-Barr virus and management of nasopharyngeal carcinoma.

    Science.gov (United States)

    Nakanishi, Yosuke; Wakisaka, Naohiro; Kondo, Satoru; Endo, Kazuhira; Sugimoto, Hisashi; Hatano, Miyako; Ueno, Takayoshi; Ishikawa, Kazuya; Yoshizaki, Tomokazu

    2017-09-01

    Nasopharyngeal carcinoma (NPC) is very common in southern China and Southeast Asia. In regions where NPC is endemic, undifferentiated subtypes constitute most cases and are invariably associated with Epstein-Barr virus (EBV) infection, whereas the differentiated subtype is more common in other parts of the world. Undifferentiated NPC is a unique malignancy with regard to its epidemiology, etiology, and clinical presentation. Clinically, NPC is highly invasive and metastatic, but sensitive to both chemotherapy and radiotherapy (RT). Overall prognosis has dramatically improved over the past three decades because of advances in management, including the improvement of RT technology, the broader application of chemotherapy, and more accurate disease staging. Despite the excellent local control with modern RT, distant failure remains a challenging problem. Advances in molecular technology have helped to elucidate the molecular pathogenesis of NPC. This article reviews the contribution of EBV gene products to NPC pathogenesis and the current management of NPC.

  11. Limited brain metabolism changes differentiate between the progression and clearance of rabies virus.

    Directory of Open Access Journals (Sweden)

    Keith Schutsky

    Full Text Available Central nervous system (CNS metabolic profiles were examined from rabies virus (RABV-infected mice that were either mock-treated or received post-exposure treatment (PET with a single dose of the live recombinant RABV vaccine TriGAS. CNS tissue harvested from mock-treated mice at middle and late stage infection revealed numerous changes in energy metabolites, neurotransmitters and stress hormones that correlated with replication levels of viral RNA. Although the large majority of these metabolic changes were completely absent in the brains of TriGAS-treated mice most likely due to the strong reduction in virus spread, TriGAS treatment resulted in the up-regulation of the expression of carnitine and several acylcarnitines, suggesting that these compounds are neuroprotective. The most striking change seen in mock-treated RABV-infected mice was a dramatic increase in brain and serum corticosterone levels, with the later becoming elevated before clinical signs or loss of body weight occurred. We speculate that the rise in corticosterone is part of a strategy of RABV to block the induction of immune responses that would otherwise interfere with its spread. In support of this concept, we show that pharmacological intervention to inhibit corticosterone biosynthesis, in the absence of vaccine treatment, significantly reduces the pathogenicity of RABV. Our results suggest that widespread metabolic changes, including hypothalamic-pituitary-adrenal axis activation, contribute to the pathogenesis of RABV and that preventing these alterations early in infection with PET or pharmacological blockade helps protect brain homeostasis, thereby reducing disease mortality.

  12. Immunity to potato mop-top virus in Nicotiana benthamiana plants expressing the coat protein gene is effective against fungal inoculation of the virus.

    Science.gov (United States)

    Reavy, B; Arif, M; Kashiwazaki, S; Webster, K D; Barker, H

    1995-01-01

    Nicotiana benthamiana stem tissue was transformed with Agrobacterium tumefaciens harboring a binary vector containing the potato mop-top virus (PMTV) coat protein (CP) gene. PMTV CP was expressed in large amounts in some of the primary transformants. The five transgenic lines which produced the most CP were selected for resistance testing. Flowers on transformed plants were allowed to self-fertilize. Transgenic seedlings selected from the T1 seed were mechanically inoculated with two strains of PMTV. Virus multiplication, assayed by infectivity, was detected in only one transgenic plant of 98 inoculated. T1 plants were also highly resistant to graft inoculation; PMTV multiplied in only one plant of 45 inoculated. Transgenic T1 seedlings were challenged in a bait test in which they were grown in soil containing viruliferous spores of the vector fungus Spongospora subterranea. In these tests only two plants out of 99 became infected. Of the five transgenic lines tested, plants of three lines were immune to infection following manual, graft, or fungal inoculation.

  13. Maize rayado fino virus virus-like particles expressed in tobacco plants: A new platform for cysteine selective bioconjugation peptide display.

    Science.gov (United States)

    Natilla, Angela; Hammond, Rosemarie W

    2011-12-01

    Maize rayado fino virus (MRFV) virus-like-particles (VLPs) produced in tobacco plants were examined for their ability to serve as a novel platform to which a variety of peptides can be covalently displayed when expressed through a Potato virus X (PVX)-based vector. To provide an anchor for chemical modifications, three Cys-MRFV-VLPs mutants were created by substituting several of the amino acids present on the shell of the wild-type MRFV-VLPs with cysteine residues. The mutant designated Cys 2-VLPs exhibited, under native conditions, cysteine thiol reactivity in bioconjugation reactions with a fluorescent dye. In addition, this Cys 2-VLPs was cross-linked by NHS-PEG4-Maleimide to 17 (F) and 8 (HN) amino acid long peptides, corresponding to neutralizing epitopes of Newcastle disease virus (NDV). The resulting Cys 2-VLPs-F and Cys 2-VLPs-HN were recognized in Western blots by antibodies to MRFV as well as to F and HN. The results demonstrated that plant-produced MRFV-VLPs have the ability to function as a novel platform for the multivalent display of surface ligands. Published by Elsevier B.V.

  14. Proteomic Analysis of Interaction between a Plant Virus and Its Vector Insect Reveals New Functions of Hemipteran Cuticular Protein.

    Science.gov (United States)

    Liu, Wenwen; Gray, Stewart; Huo, Yan; Li, Li; Wei, Taiyun; Wang, Xifeng

    2015-08-01

    Numerous viruses can be transmitted by their corresponding vector insects; however, the molecular mechanisms enabling virus transmission by vector insects have been poorly understood, especially the identity of vector components interacting with the virus. Here, we used the yeast two-hybrid system to study proteomic interactions of a plant virus (Rice stripe virus, RSV, genus Tenuivirus) with its vector insect, small brown planthopper (Laodelphax striatellus). Sixty-six proteins of L. striatellus that interacted with the nucleocapsid protein (pc3) of RSV were identified. A virus-insect interaction network, constructed for pc3 and 29 protein homologs of Drosophila melanogaster, suggested that nine proteins might directly interact with pc3. Of the 66 proteins, five (atlasin, a novel cuticular protein, jagunal, NAC domain protein, and vitellogenin) were most likely to be involved in viral movement, replication, and transovarial transmission. This work also provides evidence that the novel cuticular protein, CPR1, from L. striatellus is essential for RSV transmission by its vector insect. CPR1 binds the nucleocapsid protein (pc3) of RSV both in vivo and in vitro and colocalizes with RSV in the hemocytes of L. striatellus. Knockdown of CPR1 transcription using RNA interference resulted in a decrease in the concentration of RSV in the hemolymph, salivary glands and in viral transmission efficiency. These data suggest that CPR1 binds RSV in the insect and stabilizes the viral concentration in the hemolymph, perhaps to protect the virus or to help move the virus to the salivary tissues. Our studies provide direct experimental evidence that viruses can use existing vector proteins to aid their survival in the hemolymph. Identifying these putative vector molecules should lead to a better understanding of the interactions between viruses and vector insects. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

  15. The induction of stromule formation by a plant DNA-virus in epidermal leaf tissues suggests a novel intra- and intercellular macromolecular trafficking route

    Directory of Open Access Journals (Sweden)

    Björn eKrenz

    2012-12-01

    Full Text Available Stromules are dynamic thin protrusions of membrane envelope from plant cell plastids. Despite considerable progress in understanding the importance of certain cytoskeleton elements and motor proteins for stromule maintenance, their function within the cell has yet to be unraveled. Several viruses cause a remodulation of plastid structures and stromule biogenesis within their host plants. For RNA-viruses these interactions were demonstrated to be relevant to the infection process. An involvement of plastids and stromules is assumed in the DNA-virus life cycle as well, but their functional role needs to be determined. Recent findings support a participation of heat shock cognate 70 kDa protein (cpHSC70-1-containing stromules induced by a DNA-virus infection (Abutilon mosaic virus, AbMV, Geminiviridae in intra- and intercellular molecule exchange. The chaperone cpHSC70-1 was shown to interact with the AbMV movement protein (MP. Bimolecular fluorescence complementation confirmed the interaction of cpHSC70-1 and MP, and showed a homo-oligomerization of either protein in planta. The complexes were detected at the cellular margin and co-localized with plastids. In healthy plant tissues cpHSC70-1-oligomers occurred in distinct spots at chloroplasts and in small filaments extending from plastids to the cell periphery. AbMV-infection induced a cpHSC70-1-containing stromule network that exhibits elliptical dilations and transverses whole cells. Silencing of the cpHSC70-gene revealed an impact of cpHSC70 on chloroplast stability and restricted AbMV movement, but not viral DNA accumulation. Based on these data, a model is suggested in which these stromules function in molecule exchange between plastids and other organelles and perhaps other cells. AbMV may utilize cpHSC70-1 for trafficking along plastids and stromules into a neighboring cell or from plastids into the nucleus. Experimental approaches to investigate this hypothesis are discussed.

  16. Recent progress in the feasibility study for the first nuclear power plant in Indonesia

    International Nuclear Information System (INIS)

    Subki, I.R.; Iskandar, A.; Supadi, S.

    1994-01-01

    In September 1989 the Indonesian Government decided to perform a Nuclear Power Plant feasibility study, including a comprehensive investigation of Muris site. This presentation reports on the progress to date in the two main components of this study: (a) the non-site studies, covering energy economics, financing, technical and safety aspects, the fuel cycle and waste management as well as general management aspects, and (b) site and environmental studies, covering field investigations, assessment of site selection, site qualification/evaluation, environmental, socio-economic and cultural impacts. The study is carried out under a comprehensive quality assurance programme developed by a consultancy company - NEWJEC Inc., which compiles with IAEA recommendations and was approved by BATAN. A summary of the main results, recommendations and general conclusions is presented. It is estimated that the total investment for the construction of 2 x 900 MWe or 3 x 600 MWe class Nuclear Power Plant units would be around US$7 to US$9 billion. 8 tabs

  17. The use of short and long PCR products for improved detection of prunus necrotic ringspot virus in woody plants.

    Science.gov (United States)

    Rosner, A; Maslenin, L; Spiegel, S

    1997-09-01

    The reverse transcriptase-polymerase chain reaction (RT-PCR) was used for detection of prunus necrotic ringspot virus (PNRSV) in dormant peach and almond trees by the application of two different pairs of primers yielding a short and a long product, respectively. The relative amount of the short (200 base pair, bp) product was higher than the longer (785 bp) product. PNRSV was detected better in plant tissues with a low virus concentration (e.g. dormant trees) by amplification of the short PCR product, whereas the long product was product was produced at higher virus titers. Simultaneous amplification of both short and long products was demonstrated using a three-primer mixture in a single reaction tube. In this assay, amplification of either PCR product indicated the presence of PNRSV-specific sequences in the plant tissue examined, thus covering a wide range of virus concentrations in a single test. Dilution of the RNA extracted from infected plant material resulted in a steep decline in the amplification of both short and long PCR products. In contrast, serial dilutions of the intermediate cDNA template differentially affected the amplification patterns: the relative amount of the short product increased whereas that of the long product decreased. These results may explain the preferential amplification of the short PCR product observed in samples containing low virus concentrations.

  18. Radiation and biophysical studies on cells and viruses. Progress report, April 1, 1976--June 30, 1977

    International Nuclear Information System (INIS)

    Cole, A.

    1977-01-01

    Progress is reported on the following research projects: genetic structure of DNA, chromosomes, and nucleoproteins; particle beam studies of radiosensitive sites; division delay in CHO cells induced by partly penetrating alpha particles; location of cellular sites for mutation induction; sites for radioinduced cell transformation using partly penetrating particle beams; gamma-ray and particle irradiation of nucleoproteins and other model systems; quantitation of surface antigens on normal and neoplastic cells by x-ray fluorescence; hyperthermic effects on cell survival and DNA repair mechanisms; and studies on radioinduced cell transformation

  19. Comparative analysis among the small RNA populations of source, sink and conductive tissues in two different plant-virus pathosystems.

    Science.gov (United States)

    Herranz, Mari Carmen; Navarro, Jose Antonio; Sommen, Evelien; Pallas, Vicente

    2015-02-22

    In plants, RNA silencing plays a fundamental role as defence mechanism against viruses. During last years deep-sequencing technology has allowed to analyze the sRNA profile of a large variety of virus-infected tissues. Nevertheless, the majority of these studies have been restricted to a unique tissue and no comparative analysis between phloem and source/sink tissues has been conducted. In the present work, we compared the sRNA populations of source, sink and conductive (phloem) tissues in two different plant virus pathosystems. We chose two cucurbit species infected with two viruses very different in genome organization and replication strategy; Melon necrotic spot virus (MNSV) and Prunus necrotic ringspot virus (PNRSV). Our findings showed, in both systems, an increase of the 21-nt total sRNAs together with a decrease of those with a size of 24-nt in all the infected tissues, except for the phloem where the ratio of 21/24-nt sRNA species remained constant. Comparing the vsRNAs, both PNRSV- and MNSV-infected plants share the same vsRNA size distribution in all the analyzed tissues. Similar accumulation levels of sense and antisense vsRNAs were observed in both systems except for roots that showed a prevalence of (+) vsRNAs in both pathosystems. Additionally, the presence of overrepresented discrete sites along the viral genome, hot spots, were identified and validated by stem-loop RT-PCR. Despite that in PNRSV-infected plants the presence of vsRNAs was scarce both viruses modulated the host sRNA profile. We compare for the first time the sRNA profile of four different tissues, including source, sink and conductive (phloem) tissues, in two plant-virus pathosystems. Our results indicate that antiviral silencing machinery in melon and cucumber acts mainly through DCL4. Upon infection, the total sRNA pattern in phloem remains unchanged in contrast to the rest of the analyzed tissues indicating a certain tissue-tropism to this polulation. Independently of the

  20. Plant virus cell-to-cell movement is not dependent on the transmembrane disposition of its movement protein.

    Science.gov (United States)

    Martínez-Gil, Luis; Sánchez-Navarro, Jesús A; Cruz, Antonio; Pallás, Vicente; Pérez-Gil, Jesús; Mingarro, Ismael

    2009-06-01

    The cell-to-cell transport of plant viruses depends on one or more virus-encoded movement proteins (MPs). Some MPs are integral membrane proteins that interact with the membrane of the endoplasmic reticulum, but a detailed understanding of the interaction between MPs and biological membranes has been lacking. The cell-to-cell movement of the Prunus necrotic ringspot virus (PNRSV) is facilitated by a single MP of the 30K superfamily. Here, using a myriad of biochemical and biophysical approaches, we show that the PNRSV MP contains only one hydrophobic region (HR) that interacts with the membrane interface, as opposed to being a transmembrane protein. We also show that a proline residue located in the middle of the HR constrains the structural conformation of this region at the membrane interface, and its replacement precludes virus movement.

  1. Plant Virus Cell-to-Cell Movement Is Not Dependent on the Transmembrane Disposition of Its Movement Protein▿ †

    Science.gov (United States)

    Martínez-Gil, Luis; Sánchez-Navarro, Jesús A.; Cruz, Antonio; Pallás, Vicente; Pérez-Gil, Jesús; Mingarro, Ismael

    2009-01-01

    The cell-to-cell transport of plant viruses depends on one or more virus-encoded movement proteins (MPs). Some MPs are integral membrane proteins that interact with the membrane of the endoplasmic reticulum, but a detailed understanding of the interaction between MPs and biological membranes has been lacking. The cell-to-cell movement of the Prunus necrotic ringspot virus (PNRSV) is facilitated by a single MP of the 30K superfamily. Here, using a myriad of biochemical and biophysical approaches, we show that the PNRSV MP contains only one hydrophobic region (HR) that interacts with the membrane interface, as opposed to being a transmembrane protein. We also show that a proline residue located in the middle of the HR constrains the structural conformation of this region at the membrane interface, and its replacement precludes virus movement. PMID:19321624

  2. Use of Tissue Culture Techniques for Producing Virus-Free Plant in Garlic and Their Identification through Real-Time PCR

    Directory of Open Access Journals (Sweden)

    Hatıra Taşkın

    2013-01-01

    Full Text Available This study was performed for comparison of meristem culture technique with shoot tip culture technique for obtaining virus-free plant, comparison of micropropagation success of two different nutrient media, and determination of effectiveness of real-time PCR assay for the detection of viruses. Two different garlic species (Allium sativum and Allium tuncelianum and two different nutrient media were used in this experiment. Results showed that Medium 2 was more successful compared to Medium 1 for both A. tuncelianum and A. sativum (Kastamonu garlic clone. In vitro plants obtained via meristem and shoot tip cultures were tested for determination of onion yellow dwarf virus (OYDV and leek yellow stripe virus (LYSV through real-time PCR assay. In garlic plants propagated via meristem culture, we could not detect any virus. OYDV and LYSV viruses were detected in plants obtained via shoot tip culture. OYDV virus was observed in amount of 80% and 73% of tested plants for A. tuncelianum and A. sativum, respectively. LYSV virus was found in amount of 67% of tested plants of A. tuncelianum and in amount of 87% of tested plants of A. sativum in this study.

  3. Progress on Plant-Level Components for Nuclear Fuel Recycling: Commonality

    International Nuclear Information System (INIS)

    De Almeida, Valmor F.

    2011-01-01

    Progress made in developing a common mathematical modeling framework for plant-level components of a simulation toolkit for nuclear fuel recycling is summarized. This ongoing work is performed under the DOE Nuclear Energy Advanced Modeling and Simulation (NEAMS) program, which has an element focusing on safeguards and separations (SafeSeps). One goal of this element is to develop a modeling and simulation toolkit for used nuclear fuel recycling. The primary function of the SafeSeps simulation toolkit is to enable the time-dependent coupling of separation modules and safeguards tools (either native or third-party supplied) that simulate and/or monitor the individual separation processes in a separations plant. The toolkit integration environment will offer an interface for the modules to register in the toolkit domain based on the commonality of diverse unit operations. This report discusses the source of this commonality from a combined mathematical modeling and software design perspectives, and it defines the initial basic concepts needed for development of application modules and their integrated form, that is, an application software. A unifying mathematical theory of chemical thermomechanical network transport for physicochemical systems is proposed and outlined as the basis for developing advanced modules. A program for developing this theory from the underlying first-principles continuum thermomechanics will be needed in future developments; accomplishment of this task will enable the development of a modern modeling approach for plant-level models. Rigorous, advanced modeling approaches at the plant-level can only proceed from the development of reduced (or low-order) models based on a solid continuum field theory foundation. Such development will pave the way for future programmatic activities on software verification, simulation validation, and model uncertainty quantification on a scientific basis; currently, no satisfactory foundation exists for

  4. Progress on Plant-Level Components for Nuclear Fuel Recycling: Commonality

    Energy Technology Data Exchange (ETDEWEB)

    de Almeida, Valmor F. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2011-08-15

    Progress made in developing a common mathematical modeling framework for plant-level components of a simulation toolkit for nuclear fuel recycling is summarized. This ongoing work is performed under the DOE Nuclear Energy Advanced Modeling and Simulation (NEAMS) program, which has an element focusing on safeguards and separations (SafeSeps). One goal of this element is to develop a modeling and simulation toolkit for used nuclear fuel recycling. The primary function of the SafeSeps simulation toolkit is to enable the time-dependent coupling of separation modules and safeguards tools (either native or third-party supplied) that simulate and/or monitor the individual separation processes in a separations plant. The toolkit integration environment will offer an interface for the modules to register in the toolkit domain based on the commonality of diverse unit operations. This report discusses the source of this commonality from a combined mathematical modeling and software design perspectives, and it defines the initial basic concepts needed for development of application modules and their integrated form, that is, an application software. A unifying mathematical theory of chemical thermomechanical network transport for physicochemical systems is proposed and outlined as the basis for developing advanced modules. A program for developing this theory from the underlying first-principles continuum thermomechanics will be needed in future developments; accomplishment of this task will enable the development of a modern modeling approach for plant-level models. Rigorous, advanced modeling approaches at the plant-level can only proceed from the development of reduced (or low-order) models based on a solid continuum field theory foundation. Such development will pave the way for future programmatic activities on software verification, simulation validation, and model uncertainty quantification on a scientific basis; currently, no satisfactory foundation exists for

  5. Diverse mechanisms of plant resistance to cauliflower mosaic virus revealed by leaf skeleton hybridization.

    Science.gov (United States)

    Melcher, U; Brannan, C M; Gardner, C O; Essenberg, R C

    1992-01-01

    Plants not hosts for cauliflower mosaic virus (CaMV) may prevent systemic CaMV infection by interfering with dissemination of infection through the plant or by preventing viral replication and maturation. Leaf skeleton hybridization allows distinction between these two barriers. The technique assesses the spatial distribution of CaMV in an inoculated leaf by hybridization of a skeleton of the leaf with a CaMV DNA probe. Leaves or leaflets of soybean, cucumber, peanut, tomato, lettuce, spinach, pepper, onion, wheat, maize and barley, inoculated with CaMV DNA or CaMV virions were processed for leaf skeleton hybridization either immediately after inoculation or two weeks thereafter. Autoradiographic images of soybean and cucumber skeletons had many dark spots suggesting that CaMV DNA replication and local spread had occurred. Images of onion leaf skeletons prepared two weeks after inoculation with CaMV DNA had fewer spots. To test whether these spots resulted from CaMV replication, DNA was extracted from inoculated onion leaves and analyzed by electrophoresis, blotting and hybridization. Molecules recovered two weeks after inoculation resembled those inoculated, indicating absence of replication. For the other species, we found no evidence of local spread of CaMV infections. Thus, many plant species resist systemic CaMV infection by preventing replication or local spread of CaMV, while others solely prevent systemic movement of infection.

  6. The Community's research and development programme on decommissioning of nuclear power plants. Fourth annual progress report (year 1983)

    International Nuclear Information System (INIS)

    Anon.

    1985-01-01

    This is the fourth progress report of the European Community's program. (1979-83) of research on decommissioning of nuclear power plants. It covers the year 1983 and follows the 1980, 1981 and 1982 reports (EUR 7440, EUR 8343, EUR 8962). The present report describes the further progress of research and contains a large amount of results. For a majority of the 51 research contracts composing the 1979-83 programme, work was completed by the end of 1983; the conclusions drawn from this work are in this report. The European Community's program deals with the following fields: long-term integrity of buildings and systems; decontamination for decommissioning purposes; dismantling techniques; treatment of specific wastes materials (steel, concrete and graphite); large transport containers for radioactive waste produced in the dismantling of nuclear power plants; estimation of the quantities of radioactive waste arising from the decommissioning of nuclear power plants in the Community; influence of nuclear power plant design features on decommissioning

  7. Linear-motion tattoo machine and prefabricated needle sets for the delivery of plant viruses by vascular puncture inoculation

    Science.gov (United States)

    Vascular puncture inoculation (VPI) of plant viruses previously has been conducted either manually or by use of a commercial engraving tool and laboratory-fabricated needle arrays. In an effort to improve this technique, a linear-motion tattoo machine driving industry-standard needle arrays was tes...

  8. Radiation and biophysical studies on cells and viruses. Progress report, February 29, 1974--March 31, 1975

    International Nuclear Information System (INIS)

    Cole, A.

    Progress is reported on the following research projects: sedimentation analysis of chromosome components from interphase and mitotic chromosomes; electron microscopy of mitotic chromosomes; radiosensitive site analysis using short range particle beams; studies on nucleoproteins and DNA; RBE and OER for double strand breaks and single strand breaks of DNA irradiated with 241 Am alpha particles; use of 241 Am alpha particle track-ends to study the location of radiosensitive sites; gamma irradiation of nucleoprotein model systems; assembly of new equipment for the analysis of DNA size distributions; cell rejoining of DNA breaks induced by various radiations; studies on cell transformation induced by gamma radiation; localization of cellular sites for DNA breakage using labeled specific antibodies; and semiconductor properties of melanins related to preferential killing of melanoma cells. (U.S.)

  9. Supervised learning classification models for prediction of plant virus encoded RNA silencing suppressors.

    Directory of Open Access Journals (Sweden)

    Zeenia Jagga

    Full Text Available Viral encoded RNA silencing suppressor proteins interfere with the host RNA silencing machinery, facilitating viral infection by evading host immunity. In plant hosts, the viral proteins have several basic science implications and biotechnology applications. However in silico identification of these proteins is limited by their high sequence diversity. In this study we developed supervised learning based classification models for plant viral RNA silencing suppressor proteins in plant viruses. We developed four classifiers based on supervised learning algorithms: J48, Random Forest, LibSVM and Naïve Bayes algorithms, with enriched model learning by correlation based feature selection. Structural and physicochemical features calculated for experimentally verified primary protein sequences were used to train the classifiers. The training features include amino acid composition; auto correlation coefficients; composition, transition, and distribution of various physicochemical properties; and pseudo amino acid composition. Performance analysis of predictive models based on 10 fold cross-validation and independent data testing revealed that the Random Forest based model was the best and achieved 86.11% overall accuracy and 86.22% balanced accuracy with a remarkably high area under the Receivers Operating Characteristic curve of 0.95 to predict viral RNA silencing suppressor proteins. The prediction models for plant viral RNA silencing suppressors can potentially aid identification of novel viral RNA silencing suppressors, which will provide valuable insights into the mechanism of RNA silencing and could be further explored as potential targets for designing novel antiviral therapeutics. Also, the key subset of identified optimal features may help in determining compositional patterns in the viral proteins which are important determinants for RNA silencing suppressor activities. The best prediction model developed in the study is available as a

  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. Induction and maintenance of DNA methylation in plant promoter sequences by apple latent spherical virus-induced transcriptional gene silencing

    Directory of Open Access Journals (Sweden)

    Tatsuya eKon

    2014-11-01

    Full Text Available Apple latent spherical virus (ALSV is an efficient virus-induced gene silencing vector in functional genomics analyses of a broad range of plant species. Here, an Agrobacterium-mediated inoculation (agroinoculation system was developed for the ALSV vector, and virus-induced transcriptional gene silencing (VITGS is described in plants infected with the ALSV vector. The cDNAs of ALSV RNA1 and RNA2 were inserted between the CaMV 35S promoter and the NOS-T sequences in a binary vector pCAMBIA1300 to produce pCALSR1 and pCALSR2-XSB or pCALSR2-XSB/MN. When these vector constructs were agroinoculated into Nicotiana benthamiana plants with a construct expressing a viral silencing suppressor, the infection efficiency of the vectors was 100%. A recombinant ALSV vector carrying part of the 35S promoter sequence induced transcriptional gene silencing of the green fluorescent protein gene in a line of N. benthamiana plants, resulting in the disappearance of green fluorescence of infected plants. Bisulfite sequencing showed that cytosine residues at CG and CHG sites of the 35S promoter sequence were highly methylated in the silenced generation 0 plants infected with the ALSV carrying the promoter sequence as well as in progeny. The ALSV-mediated VITGS state was inherited by progeny for multiple generations. In addition, induction of VITGS of an endogenous gene (chalcone synthase-A was demonstrated in petunia plants infected with an ALSV vector carrying the native promoter sequence. These results suggest that ALSV-based vectors can be applied to study DNA methylation in plant genomes, and provide a useful tool for plant breeding via epigenetic modification.

  12. Expression of Separate Proteins in the Same Plant Leaves and Cells Using Two Independent Virus-Based Gene Vectors

    Directory of Open Access Journals (Sweden)

    Maria R. Mendoza

    2017-11-01

    Full Text Available Plant viral vectors enable the expression of proteins at high levels in a relatively short time. For many purposes (e.g., cell biological interaction studies it may be desirable to express more than one protein in a single cell but that is often not feasible when using a single virus vector. Such a co-expression strategy requires the simultaneous delivery by two compatible and non-competitive viruses that can co-exist to each express a separate protein. Here, we report on the use of two agro-launchable coat-protein gene substitution GFP-expressing virus vector systems based on Tomato bushy stunt virus (TBSV referred to as TG, and Tobacco mosaic virus (TMV annotated as TRBO-G. TG expressed GFP in Nicotiana benthamiana, tomato, lettuce and cowpea, whereas expression from TRBO-G was detected only in the first two species. Upon co-infiltration of the two vectors co-expression was monitored by: molecular detection of the two slightly differently sized GFPs, suppressor-complementation assays, and using TG in combination with TRBO-RFP. All the results revealed that in N. benthamiana and tomato the TBSV and TMV vectors accumulated and expressed proteins in the same plants, the same leaves, and in the same cells. Therefore, co-expression by these two vectors provides a platform for fast and high level expression of proteins to study their cell biology or other properties.

  13. 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

  14. Development of Nested PCR-Based Specific Markers for Detection of Peach Rosette Mosaic Virus in Plant Quarantine.

    Science.gov (United States)

    Lee, S; Kim, C S; Shin, Y G; Kim, J H; Kim, Y S; Jheong, W H

    2016-03-01

    The Peach rosette mosaic virus (PRMV) is a plant pathogen of the genus Nepovirus, and has been designated as a controlled quarantine virus in Korea. In this study, a specific reverse transcription (RT)-PCR marker set, nested PCR marker set, and modified-plasmid positive control were developed to promptly and accurately diagnose PRMV at plant-quarantine sites. The final selected PRMV-specific RT-PCR marker was PRMV-N10/C70 (967 bp), and the nested PCR product of 419 bp was finally amplified. The modified-plasmid positive control, in which the SalI restriction-enzyme region (GTCGAC) was inserted, verified PRMV contamination in a comparison with the control, enabling a more accurate diagnosis. It is expected that the developed method will continuously contribute to the plant-quarantine process in Korea.

  15. 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.

  16. Random Plant Viral Variants Attain Temporal Advantages During Systemic Infections and in Turn Resist other Variants of the Same Virus.

    Science.gov (United States)

    Zhang, Xiao-Feng; Guo, Jiangbo; Zhang, Xiuchun; Meulia, Tea; Paul, Pierce; Madden, Laurence V; Li, Dawei; Qu, Feng

    2015-10-20

    Infection of plants with viruses containing multiple variants frequently leads to dominance by a few random variants in the systemically infected leaves (SLs), for which a plausible explanation is lacking. We show here that SL dominance by a given viral variant is adequately explained by its fortuitous lead in systemic spread, coupled with its resistance to superinfection by other variants. We analyzed the fate of a multi-variant turnip crinkle virus (TCV) population in Arabidopsis and N. benthamiana plants. Both wild-type and RNA silencing-defective plants displayed a similar pattern of random dominance by a few variant genotypes, thus discounting a prominent role for RNA silencing. When introduced to plants sequentially as two subpopulations, a twelve-hour head-start was sufficient for the first set to dominate. Finally, SLs of TCV-infected plants became highly resistant to secondary invasions of another TCV variant. We propose that random distribution of variant foci on inoculated leaves allows different variants to lead systemic movement in different plants. The leading variants then colonize large areas of SLs, and resist the superinfection of lagging variants in the same areas. In conclusion, superinfection resistance is the primary driver of random enrichment of viral variants in systemically infected plants.

  17. Effect of medicinal plants extracts on the incidence of mosaic disease caused by cucumber mosaic virus and growth of chili

    Science.gov (United States)

    Hamidson, H.; Damiri, N.; Angraini, E.

    2018-01-01

    This research was conducted to study the effect of the application of several extracts of medicinal plants on the incidence of mosaic disease caused by Cucumber Mosaic Virus infection on the chili (Capsicum annuum L.) plantation. A Randomized Block Design with eight treatments including control was used throughout the experiment. Treatments consisted of Azadiracta indica (A), Piper bitle (B), Cymbopogon citrates (C), Curcuma domestica (D), Averroa bilimbi (E), Datura stramonium (F), Annona Muricata (G) and control (H). Each treatment consist of three replications. The parameters observed were the incidence of mosaic attack due to CMV, disease severity, plant height, wet and dry weight and production (number of fruits and the weight of total fruits) each plant. Results showed that the application of medicinal plant extracts reduced the disease severity due to CMV. Extracts of Annona muricata and Datura stramonium were most effective in suppressing disease severity caused by the virus as they significantly different from control and from a number of treatment. The plants medicinal extracts were found to have increased the plant height and total weight of the plant, fruit amount and fruit weight. Extracts of Curcuma domestica, Piper bitle and Cymbopogon citrates were the third highest in fruit amount and weight and significantly different from the control.

  18. Transcriptome of the Plant Virus Vector Graminella nigrifrons, and the Molecular Interactions of Maize fine streak rhabdovirus Transmission

    Science.gov (United States)

    Chen, Yuting; Cassone, Bryan J.; Bai, Xiaodong; Redinbaugh, Margaret G.; Michel, Andrew P.

    2012-01-01

    Background Leafhoppers (Hemiptera: Cicadellidae) are plant-phloem feeders that are known for their ability to vector plant pathogens. The black-faced leafhopper (Graminella nigrifrons) has been identified as the only known vector for the Maize fine streak virus (MFSV), an emerging plant pathogen in the Rhabdoviridae. Within G. nigrifrons populations, individuals can be experimentally separated into three classes based on their capacity for viral transmission: transmitters, acquirers and non-acquirers. Understanding the molecular interactions between vector and virus can reveal important insights in virus immune defense and vector transmission. Results RNA sequencing (RNA-Seq) was performed to characterize the transcriptome of G. nigrifrons. A total of 38,240 ESTs of a minimum 100 bp were generated from two separate cDNA libraries consisting of virus transmitters and acquirers. More than 60% of known D. melanogaster, A. gambiae, T. castaneum immune response genes mapped to our G. nigrifrons EST database. Real time quantitative PCR (RT-qPCR) showed significant down-regulation of three genes for peptidoglycan recognition proteins (PGRP – SB1, SD, and LC) in G. nigrifrons transmitters versus control leafhoppers. Conclusions Our study is the first to characterize the transcriptome of a leafhopper vector species. Significant sequence similarity in immune defense genes existed between G. nigrifrons and other well characterized insects. The down-regulation of PGRPs in MFSV transmitters suggested a possible role in rhabdovirus transmission. The results provide a framework for future studies aimed at elucidating the molecular mechanisms of plant virus vector competence. PMID:22808205

  19. Transcriptome of the plant virus vector Graminella nigrifrons, and the molecular interactions of maize fine streak rhabdovirus transmission.

    Directory of Open Access Journals (Sweden)

    Yuting Chen

    Full Text Available BACKGROUND: Leafhoppers (HEmiptera: Cicadellidae are plant-phloem feeders that are known for their ability to vector plant pathogens. The black-faced leafhopper (Graminella nigrifrons has been identified as the only known vector for the Maize fine streak virus (MFSV, an emerging plant pathogen in the Rhabdoviridae. Within G. nigrifrons populations, individuals can be experimentally separated into three classes based on their capacity for viral transmission: transmitters, acquirers and non-acquirers. Understanding the molecular interactions between vector and virus can reveal important insights in virus immune defense and vector transmission. RESULTS: RNA sequencing (RNA-Seq was performed to characterize the transcriptome of G. nigrifrons. A total of 38,240 ESTs of a minimum 100 bp were generated from two separate cDNA libraries consisting of virus transmitters and acquirers. More than 60% of known D. melanogaster, A. gambiae, T. castaneum immune response genes mapped to our G. nigrifrons EST database. Real time quantitative PCR (RT-qPCR showed significant down-regulation of three genes for peptidoglycan recognition proteins (PGRP - SB1, SD, and LC in G. nigrifrons transmitters versus control leafhoppers. CONCLUSIONS: Our study is the first to characterize the transcriptome of a leafhopper vector species. Significant sequence similarity in immune defense genes existed between G. nigrifrons and other well characterized insects. The down-regulation of PGRPs in MFSV transmitters suggested a possible role in rhabdovirus transmission. The results provide a framework for future studies aimed at elucidating the molecular mechanisms of plant virus vector competence.

  20. Targeting N-Glycan Cryptic Sugar Moieties for Broad-Spectrum Virus Neutralization: Progress in Identifying Conserved Molecular Targets in Viruses of Distinct Phylogenetic Origins

    Directory of Open Access Journals (Sweden)

    Denong Wang

    2015-03-01

    Full Text Available Identifying molecular targets for eliciting broadly virus-neutralizing antibodies is one of the key steps toward development of vaccines against emerging viral pathogens. Owing to genomic and somatic diversities among viral species, identifying protein targets for broad-spectrum virus neutralization is highly challenging even for the same virus, such as HIV-1. However, viruses rely on host glycosylation machineries to synthesize and express glycans and, thereby, may display common carbohydrate moieties. Thus, exploring glycan-binding profiles of broad-spectrum virus-neutralizing agents may provide key information to uncover the carbohydrate-based virus-neutralizing epitopes. In this study, we characterized two broadly HIV-neutralizing agents, human monoclonal antibody 2G12 and Galanthus nivalis lectin (GNA, for their viral targeting activities. Although these agents were known to be specific for oligomannosyl antigens, they differ strikingly in virus-binding activities. The former is HIV-1 specific; the latter is broadly reactive and is able to neutralize viruses of distinct phylogenetic origins, such as HIV-1, severe acute respiratory syndrome coronavirus (SARS-CoV, and human cytomegalovirus (HCMV. In carbohydrate microarray analyses, we explored the molecular basis underlying the striking differences in the spectrum of anti-virus activities of the two probes. Unlike 2G12, which is strictly specific for the high-density Man9GlcNAc2Asn (Man9-clusters, GNA recognizes a number of N-glycan cryptic sugar moieties. These include not only the known oligomannosyl antigens but also previously unrecognized tri-antennary or multi-valent GlcNAc-terminating N-glycan epitopes (Tri/m-Gn. These findings highlight the potential of N-glycan cryptic sugar moieties as conserved targets for broad-spectrum virus neutralization and suggest the GNA-model of glycan-binding warrants focused investigation.

  1. A systemic increase in the recombination frequency upon local infection of Arabidopsis thaliana plants with oilseed rape mosaic virus depends on plant age, the initial inoculum concentration and the time for virus replication

    Directory of Open Access Journals (Sweden)

    Youli eYao

    2013-03-01

    Full Text Available In the past, we showed that local infection of tobacco leaves with either Tobacco mosaic virus (TMV or Oilseed rape mosaic virus (ORMV resulted in a systemic increase in the homologous recombination frequency (HRF. Later on, we showed that a similar phenomenon occurs in Arabidopsis thaliana plants infected with ORMV. Here, we tested whether the time of removing the infected leaves as well as viral titer have any effect on the degree of changes in HRF in systemic tissues. An increase in HRF in systemic non-infected tissues was more pronounced when the infected leaves were detached from the infected plants at 60-96 hours post infection, rather than at earlier time. Next, we found that exposure to higher concentrations of inoculum was much more efficient in triggering an increase in HRF than exposure to lower concentrations. Finally, we showed that older plants exhibited a higher increase in HRF than younger plants. We found that an increase in genome instability in systemic tissues of locally infected plants depends on plant age, the concentration of initial inoculums and the time of viral replication.

  2. In vitro evaluation of novel antiviral activities of 60 medicinal plants extracts against hepatitis B virus.

    Science.gov (United States)

    Arbab, Ahmed Hassan; Parvez, Mohammad Khalid; Al-Dosari, Mohammed Salem; Al-Rehaily, Adnan Jathlan

    2017-07-01

    Currently, >35 Saudi Arabian medicinal plants are traditionally used for various liver disorders without a scientific rationale. This is the first experimental evaluation of the anti-hepatitis B virus (HBV) potential of the total ethanolic and sequential organic extracts of 60 candidate medicinal plants. The extracts were tested for toxicity on HepG2.2.15 cells and cytotoxicity concentration (CC 50 ) values were determined. The extracts were further investigated on HepG2.2.15 cells for anti-HBV activities by analyzing the inhibition of HBsAg and HBeAg production in the culture supernatants, and their half maximal inhibitory concentration (IC 50 ) and therapeutic index (TI) values were determined. Of the screened plants, Guiera senegalensis (dichloromethane extract, IC 50 =10.65), Pulicaria crispa (ethyl acetate extract, IC 50 =14.45), Coccinea grandis (total ethanol extract, IC 50 =31.57), Fumaria parviflora (hexane extract, IC 50 =35.44), Capparis decidua (aqueous extract, IC 50 =66.82), Corallocarpus epigeus (total ethanol extract, IC 50 =71.9), Indigofera caerulea (methanol extract, IC 50 =73.21), Abutilon figarianum (dichloromethane extract, IC 50 =99.76) and Acacia oerfota (total ethanol extract, IC 50 =101.46) demonstrated novel anti-HBV activities in a time- and dose-dependent manner. Further qualitative phytochemical analysis of the active extracts revealed the presence of alkaloids, tannins, flavonoids and saponins, which are attributed to antiviral efficacies. In conclusion, P. crispa, G. senegalensis and F. parviflora had the most promising anti-HBV potentials, including those of C. decidua , C. epigeus, A. figarianum , A. oerfota and I. caerulea with marked activities. However, a detailed phytochemical study of these extracts is essential to isolate the active principle(s) responsible for their novel anti-HBV potential.

  3. Ecological Fitness of Non-vector Planthopper Sogatella furcifera on Rice Plants Infected with Rice Black Streaked Dwarf Virus

    Directory of Open Access Journals (Sweden)

    Xiao-chan HE

    2012-12-01

    Full Text Available We evaluated the effects of rice black streak dwarf virus (RBSDV-infested rice plants on the ecological parameters and its relevant defensive and detoxification enzymes of white-backed planthopper (WBPH in laboratory for exploring the relationship between RBSDV and the non-vector planthopper. The results showed that nymph survival rate, female adult weight and fecundity, and egg hatchability of WBPH fed on RBSDV-infested rice plants did not markedly differ from those on healthy plants, whereas the female adult longevity and egg duration significantly shortened on diseased plants. Furthermore, significantly higher activities of defensive enzymes (dismutase, catalase and peroxidase and detoxification enzymes (acetylcholinesterase, carboxylesterase and glutathione S-transferase were found in WBPH adults fed on infected plants. Results implied that infestation by RBSDV increased the ecological fitness of non-vector planthopper population.

  4. Solanum venturii, a suitable model system for virus-induced gene silencing studies in potato reveals StMKK6 as an important player in plant immunity

    NARCIS (Netherlands)

    Dobnik, David; Lazar, Ana; Stare, Tjaša; Gruden, Kristina; Vleeshouwers, Vivianne G.A.A.; Žel, Jana

    2016-01-01

    Background: Virus-induced gene silencing (VIGS) is an optimal tool for functional analysis of genes in plants, as the viral vector spreads throughout the plant and causes reduced expression of selected gene over the whole plant. Potato (Solanum tuberosum) is one of the most important food crops,

  5. Exploring the role of cellular homologous of the 30K-superfamily of plant virus movement proteins.

    Science.gov (United States)

    Carrasco, José L; Sánchez-Navarro, Jesús A; Elena, Santiago F

    2018-02-21

    Genes orthologous to the 30K-superfamily of movement proteins (MP) from plant viruses have been recently discovered by bioinformatics analyses as integrated elements in the genome of most vascular plants. However, their functional relevance for plants is still unclear. Here, we undertake some preliminary steps into the functional characterization of one of these putative MP genes found in Arabidopsis thaliana. We found that the AtMP gene is expressed at different stages of the plant development, with accumulation being highest in flowers but lowest in mature siliques. We also found down-regulation of the gene may result in a small delay in plant development and in an exacerbation of the negative effect of salinity in germination efficiency. We have also explored whether changes in expression of the endogenous AtMP have any effect on susceptibility to infection with several viruses, and found that the infectivity of tobacco rattle tobravirus was strongly dependent on the expression of the endogenous AtMP. Finally, we have cloned the endogenous MP from four different plant species into an expression vector that allows for specifically assessing their activity as cell-to-cell movement proteins and have shown that though some may still retain the ancestral activity, they do so in a quite inefficient manner, thus suggesting they have acquired a novel function during adaptation to the host genome. Copyright © 2018 Elsevier B.V. All rights reserved.

  6. Experience with a pilot plant for the irradiation of sewage sludge: Experiments on the inactivation of viruses in sewage sludge after radiation treatment

    International Nuclear Information System (INIS)

    Epp, C.

    1975-01-01

    Investigations examining the virus inactivating effect of a 60 Co-plant have up to now been limited to attempts to isolate virus from sludge samples taken from sewage sludge before and after irradiation with 300 krad. As in these sludge samples the presence of virus could be proved only on a rather irregular basis, an experiment was carried out in which defined virus quantities were packed into capsules and mixed with the digested sludge. At the end of the hygienization process these capsules were removed from the sludge and examined for virus content. In addition one radiation volume (5.6 m 3 ) was infected with attenuated polio virus type I and the virus content of the sludge titrated before and after the radiation treatment. (author)

  7. Somatic embryogenesis from seeds in a broad range of Vitis vinifera L. varieties: rescue of true-to-type virus-free plants.

    Science.gov (United States)

    San Pedro, Tània; Gammoudi, Najet; Peiró, Rosa; Olmos, Antonio; Gisbert, Carmina

    2017-11-29

    Somatic embryogenesis is the preferred method for cell to plant regeneration in Vitis vinifera L. However, low frequencies of plant embryo conversion are commonly found. In a previous work we obtained from cut-seeds of a grapevine infected with the Grapevine leafroll associated viruses 1 and 3 (GLRaV-1 and GLRaV-3), high rates of direct regeneration, embryo plant conversion and sanitation. The aim of this study is to evaluate the usefulness of this procedure for regeneration of other grapevine varieties which include some infected with one to three common grapevine viruses (GLRaV-3, Grapevine fanleaf virus (GFLV) and Grapevine fleck virus (GFkV)). As grapevine is highly heterozygous, it was necessary to select from among the virus-free plants those that regenerated from mother tissues around the embryo, (true-to-type). Somatic embryogenesis and plant regeneration were achieved in a first experiment, using cut-seeds from the 14 grapevine varieties Airén, Cabernet Franc, Cabernet Sauvignon, Mencía, Merlot, Monastrell, Petit Verdot, Pinot Blanc (infected by GFLV and GFkV), Pinot Gris, Pinot Meunier, Pinot Noir, Syrah, Tempranillo (infected by GFLV), and Verdil. All regenerated plants were confirmed to be free of GFkV whereas at least 68% sanitation was obtained for GFLV. The SSR profiles of the virus-free plants showed, in both varieties, around 10% regeneration from mother tissue (the same genetic make-up as the mother plant). In a second experiment, this procedure was used to sanitize the varieties Cabernet Franc, Godello, Merlot and Valencí Blanc infected by GLRaV-3, GFkV and/or GFLV. Cut-seeds can be used as explants for embryogenesis induction and plant conversion in a broad range of grapevine varieties. The high regeneration rates obtained with this procedure facilitate the posterior selection of true-to-type virus-free plants. A sanitation rate of 100% was obtained for GFkV as this virus is not seed-transmitted. However, the presence of GLRaV-3 and GFLV in

  8. Identification of minimal sequences of the Rhopalosiphum padi virus 5' untranslated region required for internal initiation of protein synthesis in mammalian, plant and insect translation systems

    DEFF Research Database (Denmark)

    Groppelli, Elisabetta; Belsham, Graham; Roberts, Lisa O.

    2007-01-01

    Rhopalosiphum padi virus (RhPV) is a member of the family Dicistroviridae. The genomes of viruses in this family contain two open reading frames, each preceded by distinct internal ribosome entry site (IRES) elements. The RhPV 5' IRES is functional in mammalian, insect and plant translation syste...

  9. Amplicon based RNA interference targeting V2 gene of cotton leaf curl Kokhran virus-Burewala strain can provide resistance in transgenic cotton plants

    Science.gov (United States)

    An RNAi based gene construct designated “C2” was used to target the V2 region of the cotton leaf curl virus (CLCuV) genome which is responsible for virus movement. The construct was transformed into two elite cotton varieties MNH-786 and VH-289. A shoot apex method of plant transformation using Agr...

  10. Blueberry (Vaccinium corymbosum)-Virus Diseases

    Science.gov (United States)

    At least six viruses have been found in highbush blueberry plantings in the Pacific Northwest: Blueberry mosaic virus, Blueberry red ringspot virus, Blueberry scorch virus, Blueberry shock virus, Tobacco ringspot virus, and Tomato ringspot virus. Six other virus and virus-like diseases of highbush b...

  11. A 1-Year Quantitative Survey of Noro-, Adeno-, Human Boca-, and Hepatitis E Viruses in Raw and Secondarily Treated Sewage from Two Plants in Norway.

    Science.gov (United States)

    Myrmel, M; Lange, H; Rimstad, E

    2015-09-01

    A study of enteric viruses in raw and treated sewage from two secondary treatment plants, which received sewage from Oslo city (plant A) and small municipalities in Hedmark county in Norway (plant B), showed high levels of noro-, adeno-, and bocavirus throughout the year. A seasonal variation was observed for adeno- and GII norovirus with higher levels during winter and bocavirus that had more positive samples during winter. The virus concentrations in raw sewage were comparable in the two plants, with medians (log10 genome copies per liter) of 6.1, 6.3, 6.0, and 4.5 for noro GI, noro GII, adeno-, and bocavirus, respectively. The level of hepatitis E virus was not determined as it was below the limit of quantification. The mean log10 virus reduction was 0.55 (plant A) and 1.44 (plant B) with the highest reduction found in the plant with longer hydraulic retention time. The adenoviruses were dominantly serotype 41, while serotype 12 appeared sporadically. Of the 102 raw and treated sewage samples that were tested, eight were positive for hepatitis E virus of which four were from treated sewage. Two of the four obtained gene sequences from hepatitis E virus originated from the rural sewage samples and showed high similarity with a genotype 3 strain of hepatitis E virus detected in local piglets. Two other hepatitis E virus sequences obtained from urban sewage samples showed high similarities with genotype 3 strains isolated from urban sewage in Spain and a human genotype 1 isolate from India. The study gives information on the levels of noroviruses in raw and treated sewage, which is valuable to risk assessment, information indicating that some infections with hepatitis E viruses in Norway have a regional origin and that human bocavirus 2 and 3 are prevalent in the Norwegian population.

  12. Susceptibility of peach GF 305 seedlings and selected herbaceous plants to plum pox virus isolates from western Slovakia.

    Science.gov (United States)

    Glasa, M; Matisová, J; Hricovský, I; Kúdela, O

    1997-12-01

    The susceptibility of peach GF 305 seedlings and herbaceous plants to five plum pox virus (PPV) isolates from orchards of western Slovakia was investigated. PPV was isolated from diseased plum, apricot and peach trees, and transmitted by chip-budding to peach GF 305. The herbaceous plants were infected by mechanical inoculation. The transmission was analysed by symptomatology and double sandwich enzyme-linked immunosorbent assay (DAS-ELISA). Infected peaches developed leaf distortion, tissue clearing along the veins and small chlorotic spots (isolate BOR-3). With exception of BOR-3, the PPV isolates transmitted from peach caused local chlorotic spots on Chenopodium foetidum. The character of symptoms changed when a sap from PPV-infected Nicotiana benthamiana was used as virus inoculum. From N. benthamiana, the PPV isolates could be transmitted to Pisum sativum, cv. Colmo (light green mosaic), N. clevelandii and N. clevelandii x N. glutinosa hybrid (latent infection or chlorotic spots).

  13. Methodology of molecular diagnose of the Dashen Mosaic Virus for the certification of commercial clones of dashen in vitro plants

    Directory of Open Access Journals (Sweden)

    José E. González Rámirez

    2005-01-01

    Full Text Available The quick propagation of Dasheen clones (Xanthosoma spp and (Colocasia esculenta L. through biotechnical techniques has generated a great demand of free of diseases lines, especially to the Dasheen Mosaic Virus, this pathogen, belonging to the potivirus group, is the most important viral disease that affect the crop leading up to 40% of yield losses. The UM-ELISA diagnostic useded in massive certification programs, with big advantages over other kinds of analysis, has a limit of sensibility that can allow escape of contaminated vegetal material. With the introduction of molecular techniques of diagnostic small viral concentrations can be detected in vitroplants. In the present work, the detection of the Dasheen Mosaic Virus using the technique of reverse transcription and polymerase chain reaction is carried out. The established methodology was validated and lines of in vitro plants of dasheen were certified to be used in the micropropagation in biofactories. Xanthosoma Key words: Colocasia, DMV, healthy plants, RT-PCR,

  14. Systemic and oral immunogenicity of hemagglutinin protein of rinderpest virus expressed by transgenic peanut plants in a mouse model

    International Nuclear Information System (INIS)

    Khandelwal, Abha; Renukaradhya, G.J.; Rajasekhar, M.; Sita, G. Lakshmi; Shaila, M.S.

    2004-01-01

    Rinderpest causes a devastating disease, often fatal, in wild and domestic ruminants. It has been eradicated successfully using a live, attenuated vaccine from most part of the world leaving a few foci of disease in parts of Africa, the Middle East, and South Asia. We have developed transgenic peanut (Arachis hypogaea L.) plants expressing hemagglutinin (H) protein of rinderpest virus (RPV), which is antigenically authentic. In this work, we have evaluated the immunogenicity of peanut-expressed H protein using mouse model, administered parenterally as well as orally. Intraperitoneal immunization of mice with the transgenic peanut extract elicited antibody response specific to H. These antibodies neutralized virus infectivity in vitro. Oral immunization of mice with transgenic peanut induced H-specific serum IgG and IgA antibodies. The systemic and oral immunogenicity of plant-derived H in absence of any adjuvant indicates the potential of edible vaccine for rinderpest

  15. Phosphorylation coexists with O-GlcNAcylation in a plant virus protein and influences viral infection.

    Science.gov (United States)

    Martínez-Turiño, Sandra; Pérez, José De Jesús; Hervás, Marta; Navajas, Rosana; Ciordia, Sergio; Udeshi, Namrata D; Shabanowitz, Jeffrey; Hunt, Donald F; García, Juan Antonio

    2018-06-01

    Phosphorylation and O-GlcNAcylation are two widespread post-translational modifications (PTMs), often affecting the same eukaryotic target protein. Plum pox virus (PPV) is a member of the genus Potyvirus which infects a wide range of plant species. O-GlcNAcylation of the capsid protein (CP) of PPV has been studied extensively, and some evidence of CP phosphorylation has also been reported. Here, we use proteomics analyses to demonstrate that PPV CP is phosphorylated in vivo at the N-terminus and the beginning of the core region. In contrast with the 'yin-yang' mechanism that applies to some mammalian proteins, PPV CP phosphorylation affects residues different from those that are O-GlcNAcylated (serines Ser-25, Ser-81, Ser-101 and Ser-118). Our findings show that PPV CP can be concurrently phosphorylated and O-GlcNAcylated at nearby residues. However, an analysis using a differential proteomics strategy based on iTRAQ (isobaric tags for relative and absolute quantitation) showed a significant enhancement of phosphorylation at Ser-25 in virions recovered from O-GlcNAcylation-deficient plants, suggesting that crosstalk between O-GlcNAcylation and phosphorylation in PPV CP takes place. Although the preclusion of phosphorylation at the four identified phosphotarget sites only had a limited impact on viral infection, the mimicking of phosphorylation prevents PPV infection in Prunus persica and weakens infection in Nicotiana benthamiana and other herbaceous hosts, prompting the emergence of potentially compensatory second mutations. We postulate that the joint action of phosphorylation and O-GlcNAcylation in the N-proximal segment of CP allows a fine-tuning of protein stability, providing the amount of CP required in each step of viral infection. © 2017 BSPP AND JOHN WILEY & SONS LTD.

  16. High occurrence of hepatitis E virus in samples from wastewater treatment plants in Switzerland and comparison with other enteric viruses.

    OpenAIRE

    Masclaux, Frédéric G.; Hotz, Philipp; Friedli, Drita; Savova-Bianchi, Dessislava; Oppliger, Anne

    2013-01-01

    Hepatitis E virus (HEV) is responsible for many enterically transmitted viral hepatitides around the world. It is currently one of the waterborne diseases of global concern. In industrialized countries, HEV appears to be more common than previously thought, even if it is rarely virulent. In Switzerland, seroprevalence studies revealed that HEV is endemic, but no information was available on its environmental spread. The aim of this study was to investigate -using qPCR- the occurrence and conc...

  17. No influence of GB virus C on disease progression in a Danish cohort of HIV-infected men

    DEFF Research Database (Denmark)

    Ryt-Hansen, Rosa; Katzenstein, Terese L; Gerstoft, Jan

    2006-01-01

    Presumed apathogenic viruses have been suggested to play a role in HIV infection. In some cohorts of HIVpositive patients, GB virus C (GBVC) has been associated with prolonged survival and time to AIDS. We set out to address whether GBVC infection had any influence on survival in a cohort of 112...

  18. Simultaneous detection and identification of four cherry viruses by two step multiplex RT-PCR with an internal control of plant nad5 mRNA.

    Science.gov (United States)

    Noorani, Md Salik; Awasthi, Prachi; Sharma, Maheshwar Prasad; Ram, Raja; Zaidi, Aijaz Asgar; Hallan, Vipin

    2013-10-01

    A multiplex reverse transcription-polymerase chain reaction (mRT-PCR) was developed and standardized for the simultaneous detection of four cherry viruses: Cherry virus A (CVA, Genus; Capillovirus), Cherry necrotic rusty mottle virus (CNRMV, unassigned species of the Betaflexiviridae), Little cherry virus 1 (LChV-1, Genus; Closterovirus) and Prunus necrotic ringspot virus (PNRSV, Genus; Ilarvirus) with nad5 as plant internal control. A reliable and quick method for total plant RNA extraction from pome and stone fruit trees was also developed. To minimize primer dimer formation, a single antisense primer for CVA and CNRMV was used. A mixture of random hexamer and oligo (dT) primer was used for cDNA synthesis, which was highly suited and economic for multiplexing. All four viruses were detected successfully by mRT-PCR in artificially created viral RNA mixture and field samples of sweet cherry. The identity of the viruses was confirmed by sequencing. The assay could detect above viruses in diluted cDNA (10(-4)) and RNA (10(-3), except PNRSV which was detected only till ten times lesser dilution). The developed mRT-PCR will not only be useful for the detection of viruses from single or multiple infections of sweet cherry plants but also for other stone and pome fruits. The developed method will be therefore quite helpful for virus indexing, plant quarantine and certification programs. This is the first report for the simultaneous detection of four cherry viruses by mRT-PCR. Copyright © 2013 Elsevier B.V. All rights reserved.

  19. Mice orally immunized with a transgenic plant expressing the glycoprotein of Crimean-Congo hemorrhagic fever virus

    DEFF Research Database (Denmark)

    Ghiasi, Seyed Mojtaba; Salmanian, A H; Chinikar, S

    2011-01-01

    in their serum and feces, respectively. The mice in the fed/boosted group showed a significant rise in specific IgG antibodies after a single boost. Our results imply that oral immunization of animals with edible materials from transgenic plants is feasible, and further assessments are under way. In addition......While Crimean-Congo hemorrhagic fever (CCHF) has a high mortality rate in humans, the associated virus (CCHFV) does not induce clinical symptoms in animals, but animals play an important role in disease transmission to humans. Our aim in this study was to examine the immunogenicity of the CCHFV...... glycoprotein when expressed in the root and leaf of transgenic plants via hairy roots and stable transformation of tobacco plants, respectively. After confirmatory analyses of transgenic plant lines and quantification of the expressed glycoprotein, mice were either fed with the transgenic leaves or roots, fed...

  20. The community's research and development programme on decommissioning of nuclear power plants. Third annual progress report (year 1982)

    International Nuclear Information System (INIS)

    1984-01-01

    This is the third progress report of the European Community's programme (1979-83) of research on the decommissioning of nuclear power plants. It covers the year 1982 and follows the 1980 and 1981 reports (EUR 7440, EUR 8343). Since 1982 was a very active year of research under the programme, this report contains a large amount of results. Besides, the work programmes of some additional research contracts, awarded through 1982, are described

  1. Multiple different defense mechanisms are activated in the young transgenic tobacco plants which express the full length genome of the Tobacco mosaic virus, and are resistant against this virus.

    Science.gov (United States)

    Jada, Balaji; Soitamo, Arto J; Siddiqui, Shahid Aslam; Murukesan, Gayatri; Aro, Eva-Mari; Salakoski, Tapio; Lehto, Kirsi

    2014-01-01

    Previously described transgenic tobacco lines express the full length infectious Tobacco mosaic virus (TMV) genome under the 35S promoter (Siddiqui et al., 2007. Mol Plant Microbe Interact, 20: 1489-1494). Through their young stages these plants exhibit strong resistance against both the endogenously expressed and exogenously inoculated TMV, but at the age of about 7-8 weeks they break into TMV infection, with typical severe virus symptoms. Infections with some other viruses (Potato viruses Y, A, and X) induce the breaking of the TMV resistance and lead to synergistic proliferation of both viruses. To deduce the gene functions related to this early resistance, we have performed microarray analysis of the transgenic plants during the early resistant stage, and after the resistance break, and also of TMV-infected wild type tobacco plants. Comparison of these transcriptomes to those of corresponding wild type healthy plants indicated that 1362, 1150 and 550 transcripts were up-regulated in the transgenic plants before and after the resistance break, and in the TMV-infected wild type tobacco plants, respectively, and 1422, 1200 and 480 transcripts were down-regulated in these plants, respectively. These transcriptome alterations were distinctly different between the three types of plants, and it appears that several different mechanisms, such as the enhanced expression of the defense, hormone signaling and protein degradation pathways contributed to the TMV-resistance in the young transgenic plants. In addition to these alterations, we also observed a distinct and unique gene expression alteration in these plants, which was the strong suppression of the translational machinery. This may also contribute to the resistance by slowing down the synthesis of viral proteins. Viral replication potential may also be suppressed, to some extent, by the reduction of the translation initiation and elongation factors eIF-3 and eEF1A and B, which are required for the TMV replication

  2. Outside-in control -Does plant cell wall integrity regulate cell cycle progression?

    Science.gov (United States)

    Gigli-Bisceglia, Nora; Hamann, Thorsten

    2018-04-13

    During recent years it has become accepted that plant cell walls are not inert objects surrounding all plant cells but are instead highly dynamic, plastic structures. They are involved in a large number of cell biological processes and contribute actively to plant growth, development and interaction with environment. Therefore, it is not surprising that cellular processes can control plant cell wall integrity while, simultaneously, cell wall integrity can influence cellular processes. In yeast and animal cells such a bi-directional relationship also exists between the yeast/animal extra-cellular matrices and the cell cycle. In yeast, the cell wall integrity maintenance mechanism and a dedicated plasmamembrane integrity checkpoint are mediating this relationship. Recent research has yielded insights into the mechanism controlling plant cell wall metabolism during cytokinesis. However, knowledge regarding putative regulatory pathways controlling adaptive modifications in plant cell cycle activity in response to changes in the state of the plant cell wall are not yet identified. In this review, we summarize similarities and differences in regulatory mechanisms coordinating extra cellular matrices and cell cycle activity in animal and yeast cells, discuss the available evidence supporting the existence of such a mechanism in plants and suggest that the plant cell wall integrity maintenance mechanism might also control cell cycle activity in plant cells. This article is protected by copyright. All rights reserved.

  3. Modernization of existing power plants. Progress in automation and process control/observation

    International Nuclear Information System (INIS)

    Hanna, I.

    1996-01-01

    Numerous power plants are now getting on in years, and their owners have to face the question 'New plant or upgrade job ?'. Experience in the past few years has shown that in many cases modernization/upgrading of existing plants is a more favorable option than building a complete new power plant. Advantages like lower capital investment costs and avoidance of licensing risks for new plants constitute important motives for choosing the upgrade option in numerous power plants modernization projects. The defined objective here is to ensure the units' operating capability for another 20 to 25 years, sometimes supplemented by meticulous compliance with current environmental impact legislation. Another cogent argument emerges from automation engineering advances in modern-day control systems which make an effective contribution to meeting upgrading objective like: equipment/material -friendly operation, extended useful lifetime, enhanced plant reliability, enhanced plant availability, improved plant efficiency, optimized staffing levels, enhanced cost-effectiveness, compliance with today's international standards. In this context special attention is paid to the economical aspects and to the increase of plant availability. (author). 6 figs

  4. Viral recombination blurs taxonomic lines: examination of single-stranded DNA viruses in a wastewater treatment plant

    Directory of Open Access Journals (Sweden)

    Victoria M. Pearson

    2016-10-01

    Full Text Available Understanding the structure and dynamics of microbial communities, especially those of economic concern, is of paramount importance to maintaining healthy and efficient microbial communities at agricultural sites and large industrial cultures, including bioprocessors. Wastewater treatment plants are large bioprocessors which receive water from multiple sources, becoming reservoirs for the collection of many viral families that infect a broad range of hosts. To examine this complex collection of viruses, full-length genomes of circular ssDNA viruses were isolated from a wastewater treatment facility using a combination of sucrose-gradient size selection and rolling-circle amplification and sequenced on an Illumina MiSeq. Single-stranded DNA viruses are among the least understood groups of microbial pathogens due to genomic biases and culturing difficulties, particularly compared to the larger, more often studied dsDNA viruses. However, the group contains several notable well-studied examples, including agricultural pathogens which infect both livestock and crops (Circoviridae and Geminiviridae, and model organisms for genetics and evolution studies (Microviridae. Examination of the collected viral DNA provided evidence for 83 unique genotypic groupings, which were genetically dissimilar to known viral types and exhibited broad diversity within the community. Furthermore, although these genomes express similarities to known viral families, such as Circoviridae, Geminiviridae, and Microviridae, many are so divergent that they may represent new taxonomic groups. This study demonstrated the efficacy of the protocol for separating bacteria and large viruses from the sought after ssDNA viruses and the ability to use this protocol to obtain an in-depth analysis of the diversity within this group.

  5. Interactive Effects of Southern Rice Black-Streaked Dwarf Virus Infection of Host Plant and Vector on Performance of the Vector, Sogatella furcifera (Homoptera: Delphacidae).

    Science.gov (United States)

    Lei, Wenbin; Liu, Danfeng; Li, Pei; Hou, Maolin

    2014-10-01

    Performance of insect vectors can be influenced by the viruses they transmit, either directly by infection of the vectors or indirectly via infection of the host plants. Southern rice black-streaked dwarf virus (SRBSDV) is a propagative virus transmitted by the white-backed planthopper, Sogatella furcifera (Hovath). To elucidate the influence of SRBSDV on the performance of white-backed planthopper, life parameters of viruliferous and nonviruliferous white-backed planthopper fed rice seedlings infected or noninfected with SRBSDV were measured using a factorial design. Regardless of the infection status of the rice plant host, viruliferous white-backed planthopper nymphs took longer to develop from nymph to adult than did nonviruliferous nymphs. Viruliferous white-backed planthopper females deposited fewer eggs than nonviruliferous females and both viruliferous and nonviruliferous white-backed planthopper females laid fewer eggs on infected than on noninfected plants. Longevity of white-backed planthopper females was also affected by the infection status of the rice plant and white-backed planthopper. Nonviruliferous white-backed planthopper females that fed on infected rice plants lived longer than the other three treatment groups. These results indicate that the performance of white-backed planthopper is affected by SRBSDV either directly (by infection of white-backed planthopper) or indirectly (by infection of rice plant). The extended development of viruliferous nymphs and the prolonged life span of nonviruliferous adults on infected plants may increase their likelihood of transmitting virus, which would increase virus spread. © 2014 Entomological Society of America.

  6. Research progress in plant mutation by combining ion beam irradiations and tissue culture

    International Nuclear Information System (INIS)

    Zhou Linbin; Li Wenjian; Qu Ying; Li Ping

    2007-01-01

    About a new mutation breeding method which combines plant tissue culture technique with heavy ion beam irradiations were discussed in this paper with the principles, operation steps, molecular mechanisms, etc. The mutation method developed a few advantages coming from plant tissue culture, which can produce offspring by asexual ways. Meanwhile, using this method, the study of biological effects of high energy particles with different linear energy transfer values on plant tissues or cells can be explored and optimized in theory or practice. (authors)

  7. Disruption of Ethylene Responses by Turnip mosaic virus Mediates Suppression of Plant Defense against the Green Peach Aphid Vector.

    Science.gov (United States)

    Casteel, Clare L; De Alwis, Manori; Bak, Aurélie; Dong, Haili; Whitham, Steven A; Jander, Georg

    2015-09-01

    Plants employ diverse responses mediated by phytohormones to defend themselves against pathogens and herbivores. Adapted pathogens and herbivores often manipulate these responses to their benefit. Previously, we demonstrated that Turnip mosaic virus (TuMV) infection suppresses callose deposition, an important plant defense induced in response to feeding by its aphid vector, the green peach aphid (Myzus persicae), and increases aphid fecundity compared with uninfected control plants. Further, we determined that production of a single TuMV protein, Nuclear Inclusion a-Protease (NIa-Pro) domain, was responsible for changes in host plant physiology and increased green peach aphid reproduction. To characterize the underlying molecular mechanisms of this phenomenon, we examined the role of three phytohormone signaling pathways, jasmonic acid, salicylic acid, and ethylene (ET), in TuMV-infected Arabidopsis (Arabidopsis thaliana), with or without aphid herbivory. Experiments with Arabidopsis mutants ethylene insensitive2 and ethylene response1, and chemical inhibitors of ET synthesis and perception (aminoethoxyvinyl-glycine and 1-methylcyclopropene, respectively), show that the ET signaling pathway is required for TuMV-mediated suppression of Arabidopsis resistance to the green peach aphid. Additionally, transgenic expression of NIa-Pro in Arabidopsis alters ET responses and suppresses aphid-induced callose formation in an ET-dependent manner. Thus, disruption of ET responses in plants is an additional function of NIa-Pro, a highly conserved potyvirus protein. Virus-induced changes in ET responses may mediate vector-plant interactions more broadly and thus represent a conserved mechanism for increasing transmission by insect vectors across generations. © 2015 American Society of Plant Biologists. All Rights Reserved.

  8. Effects of TMEM154 haplotypes 1 and 3 on susceptibility to ovine progressive pneumonia virus following natural exposure in sheep.

    Science.gov (United States)

    Leymaster, K A; Chitko-McKown, C G; Clawson, M L; Harhay, G P; Heaton, M P

    2013-11-01

    Small ruminant lentiviruses (SRLV) adversely affect production and well-being of sheep and goats throughout much of the world. The SRLV, including ovine progressive pneumonia virus (OPPV) in North America, cause lifetime infections, and management procedures to eradicate or reduce disease prevalence are costly. Variants of ovine transmembrane protein 154 gene (TMEM154) affect susceptibility to OPPV. The primary experimental objective was to estimate additive and dominance effects of TMEM154 haplotypes 1 and 3 on susceptibility to OPPV infection following natural exposure. A group of 187 trial lambs was born and raised by mature, infected ewes to ensure natural exposure to OPPV. Parents of trial lambs were heterozygous for haplotypes 1 and 3, producing lambs with diplotypes "1 1," "1 3," and "3 3." A group of 20 sentinel lambs was born and raised by mature, uninfected ewes that were diplotype "1 1." Sentinel lambs had diplotypes "1 1" and "1 3," being sired by the same set of rams as trial lambs. Trial and sentinel lambs were comingled during the experiment. Lambs were weaned at 60 d of age, bled 1 wk after weaning, and thereafter at intervals of 4 or 5 wk until 9 mo of age when OPPV infection status was determined by use of a competitive enzyme-linked immunosorbent assay. Only 1 sentinel lamb became infected. Infection status of trial lambs was analyzed using logistic regression procedures to account for the binary nature of infection status and random effects of sires. Effects of sex, type of birth, type of rearing, age of dam, breed type of dam, and sires were not detected (P>0.20). Infection status was affected by diplotype of lamb (P=0.005), with additive (P=0.002) and dominance (P=0.052) effects identified. Predicted probabilities of infection for lambs with diplotypes "1 1," "1 3," and "3 3" were 0.094, 0.323, and 0.346, respectively. Confidence intervals for probabilities of infection for diplotypes "1 3" and "3 3" were similar, but distinct from diplotype

  9. Functional characterization of a strong bi-directional constitutive plant promoter isolated from cotton leaf curl Burewala virus.

    Directory of Open Access Journals (Sweden)

    Zainul A Khan

    Full Text Available Cotton leaf curl Burewala virus (CLCuBuV, belonging to the genus Begomovirus, possesses single-stranded monopartite DNA genome. The bidirectional promoters representing Rep and coat protein (CP genes of CLCuBuV were characterized and their efficacy was assayed. Rep and CP promoters of CLCuBuV and 35S promoter of Cauliflower mosaic virus (CaMV were fused with β-glucuronidase (GUS and green fluorescent protein (GFP reporter genes. GUS activity in individual plant cells driven by Rep, CP and 35S promoters was estimated using real-time PCR and fluorometric GUS assay. Histochemical staining of GUS in transformed tobacco (Nicotiana tabacum cv. Xanthi leaves showed highest expression driven by Rep promoter followed by 35S promoter and CP promoter. The expression level of GUS driven by Rep promoter in transformed tobacco plants was shown to be two to four-fold higher than that of 35S promoter, while the expression by CP promoter was slightly lower. Further, the expression of GFP was monitored in agroinfiltrated leaves of N. benthamiana, N. tabacum and cotton (Gossypium hirsutum plants using confocal laser scanning microscopy. Rep promoter showed strong consistent transient expression in tobacco and cotton leaves as compared to 35S promoter. The strong constitutive CLCuBuV Rep promoter developed in this study could be very useful for high level expression of transgenes in a wide variety of plant cells.

  10. Comparison of G protein sequences of South African street rabies viruses showing distinct progression of the disease in a mouse model of experimental rabies.

    Science.gov (United States)

    Seo, Wonhyo; Servat, Alexandre; Cliquet, Florence; Akinbowale, Jenkins; Prehaud, Christophe; Lafon, Monique; Sabeta, Claude

    Rabies is a fatal zoonotic disease and infections generally lead to a fatal encephalomyelitis in both humans and animals. In South Africa, domestic (dogs) and the wildlife (yellow mongoose) host species maintain the canid and mongoose rabies variants respectively. In this study, pathogenicity differences of South African canid and mongoose rabies viruses were investigated in a murine model, by assessing the progression of clinical signs and survivorship. Comparison of glycoprotein gene sequences revealed amino acid differences that may underpin the observed pathogenicity differences. Cumulatively, our results suggest that the canid rabies virus may be more neurovirulent in mice than the mongoose rabies variant. Copyright © 2017 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

  11. Experience with a pilot plant for sewage sludge: Experiments on the inactivation of viruses in sewage sludge after a radiation treatment

    International Nuclear Information System (INIS)

    Epp, C.

    1975-01-01

    Investigations examining the virus inactivating effect of a Cobalt-60-plant were, till now, limited to the attempts to isolate virus from the sludge samples taken from sewage sludge before and after irradiation with 300 krad. As in those sludge samples virus presence could be proven only on a rather irregular basis, an experiment was devised in which defined virus quantities were packed into capsules and mixed with the digested sludge. At the end of the hygienization process these capsules were removed from the sludge and examined for virus content. Furthermore one radiation volume (5.6 m 3 ) was infected with attenuated polio virus type I and the virus content was determined before and after the radiation treatment. In 33 sludge samples examined before hygienization, presence of one or several viruses occurred in 8 samples. With the 33 capsules examined after hygienization with 300 krad, only 2 showed presence of virus. Suspensions of attenuated polio virus type I packed into synthetic capsules with a medium virus dosis of 10sup(6.92) JD 50/0.1 were immersed into sludge. In 6 experiments it was found that after hygienization, virus dosis was reduced to an average value of 10sup(5.4) JD 50/0.1 ml. Accordingly, the experimental results showed that after the radiation treatment the reduction of the exposed virus was more than 90%. Under natural conditions the investigation of the sewage sludge samples showed presence of virus 4 times less after hygienization than in the samples examined before hygienization. (orig./AK) [de

  12. Infection of potato plants with potato leafroll virus changes attraction and feeding behaviour of Myzus persicae

    NARCIS (Netherlands)

    Alvarez, A.E.; Garzo, E.; Verbeek, M.; Vosman, B.; Dicke, M.; Tjallingii, W.F.

    2007-01-01

    Potato leafroll virus (PLRV; genus Polerovirus, family Luteoviridae) is a persistently transmitted circulative virus that depends on aphids for spreading. The primary vector of PLRV is the aphid Myzus persicae (Sulzer) (Homoptera: Aphididae). Solanum tuberosum L. potato cv. Kardal (Solanaceae) has a

  13. Regulation of polyamine synthesis in plants. Final progress report, July 1, 1991--December 31, 1994

    Energy Technology Data Exchange (ETDEWEB)

    Malmberg, R.L.

    1995-07-01

    This research focused on unusual post-translational modifications occuring in a arginine decarboxylase cDNA clone in oats. A novel regulatory mechanism for polyamines was explored and an attempt was made to characterize it. A plant ornithine decarboxylase cDNA was identified in Arabidopsis. Further work remains on the mechanisms of polyamine regulation and function in plants.

  14. Progress and expectations in the field of conventional power plant technology

    International Nuclear Information System (INIS)

    Simon, M.; Harder, H.

    1993-01-01

    By increasing the medium temperature of the heat supply the efficiency of the power plants will be increased and the CO 2 emission reduced. In this respect three development lines are being followed. They are: - Further development of the high temperature process, - pressure loaded processes with fluidized-bed combustion, - combined cycle power plants with coal gasification. (DG) [de

  15. Progressive Multifocal Leukoencephalopathy

    Science.gov (United States)

    ... SEARCH Definition Treatment Prognosis Clinical Trials Organizations Publications Definition Progressive multifocal leukoencephalopathy (PML) is a disease of the white matter of the brain, caused by a virus infection ...

  16. A transgenic plant cell-suspension system for expression of epitopes on chimeric Bamboo mosaic virus particles.

    Science.gov (United States)

    Muthamilselvan, Thangarasu; Lee, Chin-Wei; Cho, Yu-Hsin; Wu, Feng-Chao; Hu, Chung-Chi; Liang, Yu-Chuan; Lin, Na-Sheng; Hsu, Yau-Heiu

    2016-01-01

    We describe a novel strategy to produce vaccine antigens using a plant cell-suspension culture system in lieu of the conventional bacterial or animal cell-culture systems. We generated transgenic cell-suspension cultures from Nicotiana benthamiana leaves carrying wild-type or chimeric Bamboo mosaic virus (BaMV) expression constructs encoding the viral protein 1 (VP1) epitope of foot-and-mouth disease virus (FMDV). Antigens accumulated to high levels in BdT38 and BdT19 transgenic cell lines co-expressing silencing suppressor protein P38 or P19. BaMV chimeric virus particles (CVPs) were subsequently purified from the respective cell lines (1.5 and 2.1 mg CVPs/20 g fresh weight of suspended biomass, respectively), and the resulting CVPs displayed VP1 epitope on the surfaces. Guinea pigs vaccinated with purified CVPs produced humoral antibodies. This study represents an important advance in the large-scale production of immunopeptide vaccines in a cost-effective manner using a plant cell-suspension culture system. © 2015 Society for Experimental Biology, Association of Applied Biologists and John Wiley & Sons Ltd.

  17. Effects of radiation on model plant rice - OMICS: Recent progress and future prospects

    International Nuclear Information System (INIS)

    Rakwal, Randeep; Shibato, Junko; Agrawal, Ganesh Kumar; Imanaka, Tetsuji; Fukutani, Satoshi; Tamogami, Shigeru; Endo, Satoru; Sahoo, Sarat Kumar; Kimura, Shinzo

    2011-01-01

    This is the age of functional genomics, where genomes to high-throughput technologies and to the phenotype are making inroads into various biological questions and problems. In this report, I along with my co-workers will present an outline into the omics approaches, focusing on the global gene expression profiling (DNA microarray technique), plants and the environment, and culminating in the use of genomics to analyze the effects of radiation on plant life. For this, rice (Oryza sativa L.) geonome model and monocot cereal crop plant will be used as an example. It is our hope that use of both model and non-model plants in conjunction with high-throughput transcriptomics approaches will lead the way for unraveling radiation responses in plants, setting the stage for further research on this important aspect of our environment with direct and indirect impact on human life and civilization. (author)

  18. 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.

  19. Salicylic Acid Is Involved in the Basal Resistance of Tomato Plants to Citrus Exocortis Viroid and Tomato Spotted Wilt Virus.

    Science.gov (United States)

    López-Gresa, M Pilar; Lisón, Purificación; Yenush, Lynne; Conejero, Vicente; Rodrigo, Ismael; Bellés, José María

    2016-01-01

    Tomato plants expressing the NahG transgene, which prevents accumulation of endogenous salicylic acid (SA), were used to study the importance of the SA signalling pathway in basal defence against Citrus Exocortis Viroid (CEVd) or Tomato Spotted Wilt Virus (TSWV). The lack of SA accumulation in the CEVd- or TSWV-infected NahG tomato plants led to an early and dramatic disease phenotype, as compared to that observed in the corresponding parental Money Maker. Addition of acibenzolar-S-methyl, a benzothiadiazole (BTH), which activates the systemic acquired resistance pathway downstream of SA signalling, improves resistance of NahG tomato plants to CEVd and TSWV. CEVd and TSWV inoculation induced the accumulation of the hydroxycinnamic amides p-coumaroyltyramine, feruloyltyramine, caffeoylputrescine, and feruloylputrescine, and the defence related proteins PR1 and P23 in NahG plants earlier and with more intensity than in Money Maker plants, indicating that SA is not essential for the induction of these plant defence metabolites and proteins. In addition, NahG plants produced very high levels of ethylene upon CEVd or TSWV infection when compared with infected Money Maker plants, indicating that the absence of SA produced additional effects on other metabolic pathways. This is the first report to show that SA is an important component of basal resistance of tomato plants to both CEVd and TSWV, indicating that SA-dependent defence mechanisms play a key role in limiting the severity of symptoms in CEVd- and TSWV-infected NahG tomato plants.

  20. Salicylic Acid Is Involved in the Basal Resistance of Tomato Plants to Citrus Exocortis Viroid and Tomato Spotted Wilt Virus.

    Directory of Open Access Journals (Sweden)

    M Pilar López-Gresa

    Full Text Available Tomato plants expressing the NahG transgene, which prevents accumulation of endogenous salicylic acid (SA, were used to study the importance of the SA signalling pathway in basal defence against Citrus Exocortis Viroid (CEVd or Tomato Spotted Wilt Virus (TSWV. The lack of SA accumulation in the CEVd- or TSWV-infected NahG tomato plants led to an early and dramatic disease phenotype, as compared to that observed in the corresponding parental Money Maker. Addition of acibenzolar-S-methyl, a benzothiadiazole (BTH, which activates the systemic acquired resistance pathway downstream of SA signalling, improves resistance of NahG tomato plants to CEVd and TSWV. CEVd and TSWV inoculation induced the accumulation of the hydroxycinnamic amides p-coumaroyltyramine, feruloyltyramine, caffeoylputrescine, and feruloylputrescine, and the defence related proteins PR1 and P23 in NahG plants earlier and with more intensity than in Money Maker plants, indicating that SA is not essential for the induction of these plant defence metabolites and proteins. In addition, NahG plants produced very high levels of ethylene upon CEVd or TSWV infection when compared with infected Money Maker plants, indicating that the absence of SA produced additional effects on other metabolic pathways. This is the first report to show that SA is an important component of basal resistance of tomato plants to both CEVd and TSWV, indicating that SA-dependent defence mechanisms play a key role in limiting the severity of symptoms in CEVd- and TSWV-infected NahG tomato plants.

  1. Virus-induced plasma membrane aquaporin PsPIP2;1 silencing inhibits plant water transport of Pisum sativum.

    Science.gov (United States)

    Song, Juanjuan; Ye, Guoliang; Qian, Zhengjiang; Ye, Qing

    2016-12-01

    Aquaporins (AQPs) are known to facilitate water transport across cell membranes, but the role of a single AQP in regulating plant water transport, particularly in plants other than Arabidopsis remains largely unexplored. In the present study, a virus-induced gene silencing (VIGS) technique was employed to suppress the expression of a specific plasma membrane aquaporin PsPIP2;1 of Pea plants (Pisum sativum), and subsequent effects of the gene suppression on root hydraulic conductivity (Lp r ), leaf hydraulic conductivity (K leaf ), root cell hydraulic conductivity (Lp rc ), and leaf cell hydraulic conductivity (Lp lc ) were investigated, using hydroponically grown Pea plants. Compared with control plants, VIGS-PsPIP2;1 plants displayed a significant suppression of PsPIP2;1 in both roots and leaves, while the expression of other four PIP isoforms (PsPIP1;1, PsPIP1;2, PsPIP2;2, and PsPIP2;3) that were simultaneously monitored were not altered. As a consequence, significant declines in water transport of VIGS-PsPIP2;1 plants were observed at both organ and cell levels, i.e., as compared to control plants, Lp r and K leaf were reduced by 29 %, and Lp rc and Lp lc were reduced by 20 and 29 %, respectively. Our results demonstrate that PsPIP2;1 alone contributes substantially to root and leaf water transport in Pea plants, and highlight VIGS a useful tool for investigating the role of a single AQP in regulating plant water transport.

  2. 寨卡病毒病诊治进展%Progression of Diagnosis and Therapy of Zika Virus

    Institute of Scientific and Technical Information of China (English)

    罗伊; 冯萍

    2017-01-01

    寨卡病毒目前是世界上最紧急的病毒之一,属于黄病毒科病毒,主要依靠蚊媒传播.感染后症状与登革热类似,有自限性.成人感染病毒可能出现吉兰-巴雷综合征,孕早期妇女感染可导致新生儿小头畸形.寨卡病毒的实验室诊断方法主要包括病毒分离培养、核酸检测和血清免疫学检测,临床多采用核酸检测和血清免疫学检测结合的方式.寨卡病毒的防治目前尚无有效的疫苗和药物,临床上多采取对症支持治疗;对于普通人群,防蚊灭蚊是最经济且有效的的方法.%Zika virus has become one of the most urgent viruses in the world .The Zika virus is an arbovirus belonging to the family of Flaviviridae .The virus is mainly transmitted by the Aedes mosquitoes .The symptoms associated with Zika virus infection are generally mild ,which are similar to dengue fever ,and the course is self-limiting.There are some cases of Guillain-Barrésyndrome associated with Zika virus infection in adult ,while in pregnant women,the infection of Zika virus may cause fetal microcephaly .Diagnosis of Zika virus infection includes virus isolation ,nucleic acid detection and immuno-logical detection .The recommended way is the combination of nucleic acid detection and immunological detection .Currently there are no effective drugs or vaccines for Zika virus so the symptomatic and supportive treatment is still mostly used .At present,the most economical control measure for general population relies on public and individual strategies to cut down the mosquito population and to avoid mosquito bites .

  3. Progress in XRCS-Survey plant instrumentation and control design for ITER

    International Nuclear Information System (INIS)

    Varshney, Sanjeev; Jha, Shivakant; Simrock, Stefan; Barnsley, Robin; Martin, Vincent; Mishra, Sapna; Patil, Prabhakant; Patel, Shreyas; Kumar, Vinay

    2016-01-01

    Highlights: • An identification of the major process functions system compliant to Plant Control Design Handbook (PCDH) has been made for XRCS-Survey plant I&C. • I&C Functional Breakdown Structure (FBS) and Operation Procedure (OP) have been drafted using Enterprise architect (EA). • I&C architecture, interface with ITER networks and Plants, configuration of cubicles are discussed towards nine design review deliverables. - Abstract: A real time, plasma impurity survey system based on X-ray Crystal Spectroscopy (XRCS) has been designed for ITER and will be made available in the set of first plasma diagnostics for measuring impurity ion concentrations and their in-flux. For the purpose of developing a component level design of XRCS-Survey plant I&C system that is compliant to the rules and guidelines defined in the Plant Control Design Handbook (PCDH), firstly an identification of the major process functions has been made. The preliminary plant I&C Functional Breakdown Structure (FBS) and Operation Procedure (OP) have been drafted using a system engineering tool, Enterprise Architect (EA). Conceptual I&C architecture, interface with the ITER networks and other Plants have been discussed along with the basic configuration of I&C cubicles aiming towards nine I&C deliverables for the design review.

  4. Progress in XRCS-Survey plant instrumentation and control design for ITER

    Energy Technology Data Exchange (ETDEWEB)

    Varshney, Sanjeev, E-mail: sanjeev.varshney@iter-india.org [ITER-India, Institute for Plasma Research, Bhat, Gandhinagar, 382 428 (India); Jha, Shivakant [ITER-India, Institute for Plasma Research, Bhat, Gandhinagar, 382 428 (India); Simrock, Stefan; Barnsley, Robin; Martin, Vincent [ITER-Organization, Route de Vinon sur Verdon, CS 90 046, 13067 St. Paul-Lez-Durance, Cedex (France); Mishra, Sapna [ITER-India, Institute for Plasma Research, Bhat, Gandhinagar, 382 428 (India); Patil, Prabhakant [ITER-Organization, Route de Vinon sur Verdon, CS 90 046, 13067 St. Paul-Lez-Durance, Cedex (France); Patel, Shreyas; Kumar, Vinay [ITER-India, Institute for Plasma Research, Bhat, Gandhinagar, 382 428 (India)

    2016-11-15

    Highlights: • An identification of the major process functions system compliant to Plant Control Design Handbook (PCDH) has been made for XRCS-Survey plant I&C. • I&C Functional Breakdown Structure (FBS) and Operation Procedure (OP) have been drafted using Enterprise architect (EA). • I&C architecture, interface with ITER networks and Plants, configuration of cubicles are discussed towards nine design review deliverables. - Abstract: A real time, plasma impurity survey system based on X-ray Crystal Spectroscopy (XRCS) has been designed for ITER and will be made available in the set of first plasma diagnostics for measuring impurity ion concentrations and their in-flux. For the purpose of developing a component level design of XRCS-Survey plant I&C system that is compliant to the rules and guidelines defined in the Plant Control Design Handbook (PCDH), firstly an identification of the major process functions has been made. The preliminary plant I&C Functional Breakdown Structure (FBS) and Operation Procedure (OP) have been drafted using a system engineering tool, Enterprise Architect (EA). Conceptual I&C architecture, interface with the ITER networks and other Plants have been discussed along with the basic configuration of I&C cubicles aiming towards nine I&C deliverables for the design review.

  5. [Research progress in chemical communication among insect-resistant genetically modified plants, insect pests and natural enemies].

    Science.gov (United States)

    Liu, Qing-Song; Li, Yun-He; Chen, Xiu-Ping; Peng, Yu-Fa

    2014-08-01

    Semiochemicals released by plants or insects play an important role in the communication among plants, phytophagous insects and their natural enemies. They thus form a chemical information network which regulates intra- and inter-specific behaviors and sustains the composition and structure of plant and insect communities. The application of insect-resistant genetically modified (IRGM) crops may affect the chemical communication within and among the tritrophic levels, and thus cause disturbances to the biotic community structure and the stability of the farmland ecosystem. This has raised concerns about the environmental safety of IRGM crops and triggered research worldwide. In the current article we provided a brief summary of the chemical communication among plants, herbivores and natural enemies; analyzed the potential of IRGM crops to affect the chemical communication between plants and arthropods and the related mechanisms; and discussed the current research progress and the future prospects in this field. We hope that this will promote the research in this field by Chinese scientists and increase our understanding of the potential effects of growing of IRGM crops on the arthropod community structure.

  6. Infection cycle of Artichoke Italian latent virus in tobacco plants: meristem invasion and recovery from disease symptoms.

    Directory of Open Access Journals (Sweden)

    Elisa Santovito

    Full Text Available Nepoviral infections induce recovery in fully expanded leaves but persist in shoot apical meristem (SAM by a largely unknown mechanism. The dynamics of infection of a grapevine isolate of Artichoke Italian latent virus (AILV-V, genus Nepovirus in tobacco plants, including colonization of SAM, symptom induction and subsequent recovery of mature leaves from symptoms, were characterized. AILV-V moved from the inoculated leaves systemically and invaded SAM in 7 days post-inoculation (dpi, remaining detectable in SAM at least up to 40 dpi. The new top leaves recovered from viral symptoms earliest at 21 dpi. Accumulation of viral RNA to a threshold level was required to trigger the overexpression of RDR6 and DCL4. Consequently, accumulation of viral RNA decreased in the systemically infected leaves, reaching the lowest concentration in the 3rd and 4th leaves at 23 dpi, which was concomitant with recovery of the younger, upper leaves from disease symptoms. No evidence of virus replication was found in the recovered leaves, but they contained infectious virus particles and were protected against re-inoculation with AILV-V. In this study we also showed that AILV-V did not suppress initiation or maintenance of RNA silencing in transgenic plants, but was able to interfere with the cell-to-cell movement of the RNA silencing signal. Our results suggest that AILV-V entrance in SAM and activation of RNA silencing may be distinct processes since the latter is triggered in fully expanded leaves by the accumulation of viral RNA above a threshold level rather than by virus entrance in SAM.

  7. 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.

  8. Progress of independent feasibility study for modular HTGR demonstration plant to be built in China

    International Nuclear Information System (INIS)

    He Jiachen

    1989-01-01

    Many regions in China are suffering from shortage of energy as a result of the rapid growth of the national economy, for example, the growth rate of national production in 1988 reached 11.2%. A great number of coal fired plants have been built in many industrial areas. However, the difficulties relating to the transportation of coal and environmental pollution have become more and more serious. The construction of hydropower plants is limited due to uneven geographic conditions and seasons. For these reasons China needs to develop nuclear power plants. Nowadays, it has been decided, that PWR will be the main reactor type in our country, but in some districts or under some conditions modular HTGR may have distinct advantages and become an attractive option. The possible plant site description and preliminary result of economic analysis of modular HTGR type reactor are briefly discussed in this presentation

  9. 15. Internal symposium on recent progress of nondestructive inspection and monitoring technologies for nuclear power plants

    International Nuclear Information System (INIS)

    1994-01-01

    At the symposium, lectures were given on the recent development of the nondestructive inspection technology for nuclear power plants, the trend regarding the nondestructive inspection in foreign countries (Japan-Germany atomic energy seminar), the present state and subjects of the monitoring technology in BWR plants, the present state and subjects of the monitoring technology in PWR plants, and the present state and the subjects for hereafter of the defect evaluation method in the equipment of light water reactors. The data on the ultrasonic flaw detection in aluminum alloy welded joints were obtained. The German inspection technology is similar to that in Japan and other countries. The research on the plant synthetic monitoring and diagnosis system is reported. The monitoring systems for abnormal state in operation, troubles and the secular change of equipment are reported. The evaluation of the flaws in nuclear piping is reported. The summaries of the lectures are collected in this book. (K.I.)

  10. Pollen transmission of asparagus virus 2 (AV-2) may facilitate mixed infection by two AV-2 isolates in asparagus plants.

    Science.gov (United States)

    Kawamura, Ryusuke; Shimura, Hanako; Mochizuki, Tomofumi; Ohki, Satoshi T; Masuta, Chikara

    2014-09-01

    Asparagus virus 2 (AV-2) is a member of the genus Ilarvirus and thought to induce the asparagus decline syndrome. AV-2 is known to be transmitted by seed, and the possibility of pollen transmission was proposed 25 years ago but not verified. In AV-2 sequence analyses, we have unexpectedly found mixed infection by two distinct AV-2 isolates in two asparagus plants. Because mixed infections by two related viruses are normally prevented by cross protection, we suspected that pollen transmission of AV-2 is involved in mixed infection. Immunohistochemical analyses and in situ hybridization using AV-2-infected tobacco plants revealed that AV-2 was localized in the meristem and associated with pollen grains. To experimentally produce a mixed infection via pollen transmission, two Nicotiana benthamiana plants that were infected with each of two AV-2 isolates were crossed. Derived cleaved-amplified polymorphic sequence analysis identified each AV-2 isolate in the progeny seedlings, suggesting that pollen transmission could indeed result in a mixed infection, at least in N. benthamiana.

  11. Dengue virus receptor

    OpenAIRE

    Hidari, Kazuya I.P.J.; Suzuki, Takashi

    2011-01-01

    Dengue virus is an arthropod-borne virus transmitted by Aedes mosquitoes. Dengue virus causes fever and hemorrhagic disorders in humans and non-human primates. Direct interaction of the virus introduced by a mosquito bite with host receptor molecule(s) is crucial for virus propagation and the pathological progression of dengue diseases. Therefore, elucidation of the molecular mechanisms underlying the interaction between dengue virus and its receptor(s) in both humans and mosquitoes is essent...

  12. Plant virus-resembling optical nano-materials conjugated with anti-EGFR for targeted cancer imaging

    Science.gov (United States)

    Gupta, Sharad; Wilder, Hailey; Rao, A. L. N.; Vullev, V. I.; Anvari, Bahman

    2012-03-01

    We recently reported the construction of a new type of optically active nano-particles composed of genome-depleted plant infecting brome mosaic virus (BMV) doped with indocyanine green (ICG), an FDA-approved chromophore . We refer to these constructs as optical viral ghosts (OVGs) since only the capsid protein (CP) subunits of BMV remain to encapsulate ICG. Herein, we covalently conjugated the surface of OVGs with anti-epidermal growth factor receptors (anti-EGFR) to target cancerous human bronchial epithelial cells (C-HBECs) in-vitro. Our preliminary results demonstrate the utility of conjugated OVGs for targeted imaging of cancer cells.

  13. A plant small polypeptide is a novel component of DNA-binding protein phosphatase 1-mediated resistance to plum pox virus in Arabidopsis.

    Science.gov (United States)

    Castelló, María José; Carrasco, Jose Luis; Navarrete-Gómez, Marisa; Daniel, Jacques; Granot, David; Vera, Pablo

    2011-12-01

    DNA-binding protein phosphatases (DBPs) have been identified as a novel class of plant-specific regulatory factors playing a role in plant-virus interactions. NtDBP1 from tobacco (Nicotiana tabacum) was shown to participate in transcriptional regulation of gene expression in response to virus infection in compatible interactions, and AtDBP1, its closest relative in the model plant Arabidopsis (Arabidopsis thaliana), has recently been found to mediate susceptibility to potyvirus, one of the most speciose taxa of plant viruses. Here, we report on the identification of a novel family of highly conserved small polypeptides that interact with DBP1 proteins both in tobacco and Arabidopsis, which we have designated DBP-interacting protein 2 (DIP2). The interaction of AtDIP2 with AtDBP1 was demonstrated in vivo by bimolecular fluorescence complementation, and AtDIP2 was shown to functionally interfere with AtDBP1 in yeast. Furthermore, reducing AtDIP2 gene expression leads to increased susceptibility to the potyvirus Plum pox virus and to a lesser extent also to Turnip mosaic virus, whereas overexpression results in enhanced resistance. Therefore, we describe a novel family of conserved small polypeptides in plants and identify AtDIP2 as a novel host factor contributing to resistance to potyvirus in Arabidopsis.

  14. The Irish paradigm on the natural progression of hepatitis C virus infection: an investigation in a homogeneous patient population infected with HCV 1b (review).

    LENUS (Irish Health Repository)

    Fanning, Liam J

    2012-02-03

    The aetiological agent of chronic hepatitis C is the hepatitis C virus. The hepatitis C virus is spread by parenteral transmission of body fluids, primarily blood or blood products. In 1989, after more than a decade of research, HCV was isolated and characterised. The hepatitis C viral genome is a positive-sense, single-stranded RNA molecule approximately 9.4 kb in length, which encodes a polyprotein of about 3100 amino acids. There are 6 main genotypes of HCV, each further stratified by subtype. In 1994, a cohort of women was identified in Ireland as having been iatrogenically exposed to the hepatitis C virus. The women were all young and exposed as a consequence of the receipt of HCV 1b contaminated anti-D immunoglobulin. The source of the infection was identified as an acutely infected female. As part of a voluntary serological screening programme involving 62,667 people, 704 individuals were identified as seropositive for exposure to the hepatitis C virus; 55.4% were found to be positive for the viral genome 17 years after exposure. Of these women 98% had evidence of inflammation, but surprisingly, a remarkable 49% showed no evidence of fibrosis. Clinicopathology and virological analysis has identified associations between viral load and the histological activity index for inflammation, and, between inflammation and levels of the liver enzyme alanine aminotransferase. Infection at a younger age appears to protect individuals from progression to advanced liver disease. Molecular analyses of host immunogenetic elements shows that particular class II human leukocyte associated antigen alleles are associated with clearance of the hepatitis C virus. Additional class II alleles have been identified that are associated with stable viraemia over an extended period of patient follow-up. Although, investigation of large untreated homogeneous cohorts is likely to become more difficult, as the efficacy of anti-viral therapy improves, further investigation of host and viral

  15. Herbivore benefits from vectoring plant virus through reduction of period of vulnerability to predation

    NARCIS (Netherlands)

    Belliure, B.; Janssen, A.; Sabelis, M.W.

    2008-01-01

    Herbivores can profit from vectoring plant pathogens because the induced defence of plants against pathogens sometimes interferes with the induced defence of plants against herbivores. Plants can also defend themselves indirectly by the action of the natural enemies of the herbivores. It is unknown

  16. Research Progress on the use of Plant Allelopathy in Agriculture and the Physiological and Ecological Mechanisms of Allelopathy.

    Science.gov (United States)

    Cheng, Fang; Cheng, Zhihui

    2015-01-01

    Allelopathy is a common biological phenomenon by which one organism produces biochemicals that influence the growth, survival, development, and reproduction of other organisms. These biochemicals are known as allelochemicals and have beneficial or detrimental effects on target organisms. Plant allelopathy is one of the modes of interaction between receptor and donor plants and may exert either positive effects (e.g., for agricultural management, such as weed control, crop protection, or crop re-establishment) or negative effects (e.g., autotoxicity, soil sickness, or biological invasion). To ensure sustainable agricultural development, it is important to exploit cultivation systems that take advantage of the stimulatory/inhibitory influence of allelopathic plants to regulate plant growth and development and to avoid allelopathic autotoxicity. Allelochemicals can potentially be used as growth regulators, herbicides, insecticides, and antimicrobial crop protection products. Here, we reviewed the plant allelopathy management practices applied in agriculture and the underlying allelopathic mechanisms described in the literature. The major points addressed are as follows: (1) Description of management practices related to allelopathy and allelochemicals in agriculture. (2) Discussion of the progress regarding the mode of action of allelochemicals and the physiological mechanisms of allelopathy, consisting of the influence on cell micro- and ultra-structure, cell division and elongation, membrane permeability, oxidative and antioxidant systems, growth regulation systems, respiration, enzyme synthesis and metabolism, photosynthesis, mineral ion uptake, protein and nucleic acid synthesis. (3) Evaluation of the effect of ecological mechanisms exerted by allelopathy on microorganisms and the ecological environment. (4) Discussion of existing problems and proposal for future research directions in this field to provide a useful reference for future studies on plant

  17. Research progress on the use of plant allelopathy in agriculture and the physiological and ecological mechanisms of allelopathy

    Directory of Open Access Journals (Sweden)

    Fang eCheng

    2015-11-01

    Full Text Available Allelopathy is a common biological phenomenon by which one organism produces biochemicals that influence the growth, survival, development, and reproduction of other organisms. These biochemicals are known as allelochemicals and have beneficial or detrimental effects on target organisms. Plant allelopathy is one of the modes of interaction between receptor and donor plants and may exert either positive effects (e.g., for agricultural management, such as weed control, crop protection, or crop re-establishment or negative effects (e.g., autotoxicity, soil sickness, or biological invasion. To ensure sustainable agricultural development, it is important to exploit cultivation systems that take advantage of the stimulatory / inhibitory influence of allelopathic plants to regulate plant growth and development and to avoid allelopathic autotoxicity. Allelochemicals can potentially be used as growth regulators, herbicides, insecticides and antimicrobial crop protection products. Here, we reviewed the plant allelopathy management practices applied in agriculture and the underlying allelopathic mechanisms described in the literature. The major points addressed are as follows: (1 Description of management practices related to allelopathy and allelochemicals in agriculture. (2 Discussion of the progress regarding the mode of action of allelochemicals and the physiological mechanisms of allelopathy, consisting of the influence on cell micro- and ultra-structure, cell division and elongation, membrane permeability, oxidative and antioxidant systems, growth regulation systems, respiration, enzyme synthesis and metabolism, photosynthesis, mineral ion uptake, protein and nucleic acid synthesis. (3 Evaluation of the effect of ecological mechanisms exerted by allelopathy on microorganisms and the ecological environment. (4 Discussion of existing problems and proposal for future research directions in this field to provide a useful reference for future studies on

  18. Research projects into the safety of nuclear power plants. Period cover 01. January - 30. June 2017. Progress report

    International Nuclear Information System (INIS)

    2017-01-01

    Within its competence for energy research the Federal Ministry for Economic Affairs and Energy (BMWi) sponsors research projects on the safety of nuclear power plants currently in operation. The objective of these projects is to provide fundamental knowledge, procedures and methods to contribute to realistic safety assessments of nuclear installations, to the further development of safety technology and to make use of the potential of innovative safety-related approaches. The Gesellschaft fur Anlagen- und Reaktorsicherheit (GRS) gGmbH, by order of the BMWi, continuously issues information on the status of such research projects by publishing semi-annual and annual progress reports within the series of GRS-F-Fortschrittsberichte (GRS-F-Progress Reports). Each progress report represents a compilation of individual reports about the objectives, work performed, results achieved, next steps of the work etc. The individual reports are prepared in a standard form by the research organisations themselves as documentation of their progress in work. The progress reports are published by the Project Management Agency/ Authority Support Division of GRS. The reports as of the year 2000 are available in the internet-based information system on results and data of reactor safety research (https://www.grs-fbw.de). The compilation of the reports is classified according to the topic areas of reactor safety research. The reports are arranged in sequence of their project numbers. Ilt has to be pointed out that the authors of the reports are responsible for the contents of this compilation. The BMWi does not take any responsibility for the correctness, exactness and completeness of the information nor for the observance of private claims of third parties.

  19. Research projects into the safety of nuclear power plants. Period covered: 01. July - 31. December 2004. Progress report

    International Nuclear Information System (INIS)

    2004-01-01

    Within its competence for energy research, the Bundesministerium fuer Wirtschaft und Technology (BMWi) (Federal Ministry of Economics and Technology) sponsors investigations into the safety of nuclear power plants. The objective of these investigations is to provide fundamental knowledge, procedures and methods to contribute to realistic safety assessments of nuclear installations, to the further development of safety technology and to make use of the potential of innovative safety-related approaches. The Gesellschaft fuer Anlagen- und Reaktorsicherheit (GRS) mbH, by order of the BMWi, continuously issues information on the status of such investigations by publishing semi-annual and annual progress reports within the series of GRS-F-Fortschrittsberichte (GRS-F-Progress Reports). Each progress report represents a compilation of individual reports about the objectives, work performed, results achieved, next steps of the work etc. The individual reports are prepared in a standard form by the research organisations themselves as documentation of their progress in work and are published by the Research Management Division of GRS within the framework of general information on the progress in reactor safety research. The compilation of the reports is classified according to general topics related to reactor safety research. Further, use is made of the classification system 'Joint Safety Research Index' of the CEC (Commission of the European Communities). The reports are arranged in sequence of their project numbers. It has to be pointed out that the authors of the reports are responsible for the contents of this compilation. The BMWi does not take any responsibility for the correctness, exactness and completeness of the information nor for the observance of private claims of third parties. (orig.)

  20. Legacy for the Millennium: A Century of Progress in Plant Pathology.

    Science.gov (United States)

    Sequeira, Luis

    2000-09-01

    Plant pathology came of age at the turn of this century and we can be proud of the many significant contributions it has made to fundamental research as well as to service to growers. The twenty-first century will present our profession with dramatic challenges to meet the demands for increased food, fiber, and fuel production from a declining agricultural base. This can be accomplished only if plant pathology retains its integrity as a profession and remains abreast of advancements in the fields of biotechnology and communications.

  1. Bataan nuclear power plant unit no. 1. Progress report no. 207

    International Nuclear Information System (INIS)

    1994-08-01

    This report presents the accomplishment of the National Power Corporation (NPC) for the month of August 1994. The highlights of the report were the following: a) issuance of preservation task orders; b) total expenses for the preservation and maintenance of the plant; c) completion of underwater structures and fabrication of the stop logs; d) repaired of two dry type transformers; e) inventory of excess construction materials; and f) investigations of vehicular accident. Also in this period, delegates from different institutions and organizations and schools were given briefings and tour of the plant facilities as part of public information campaign. ills

  2. Current progress in the design and setup of a SOFC/GT hybrid power plant

    OpenAIRE

    Schnegelberger, Christian; Henke, Moritz; Tomberg, Marius; Heddrich, Marc; Friedrich, K. Andreas

    2017-01-01

    The German Aerospace Center (DLR) is setting up a hybrid power plant with 30 kW electrical power output. It consists of a SOFC and a micro gas turbine (MGT). The hybrid power plant can reach electrical system efficiencies greater than 60 % throughout a wide operating range. Due to the SOFC’s high operation temperature and incomplete fuel utilisation, the exhaust gas will always contain usable energy. The MGT will use this energy to provide compressed and preheated air for the SOFC and ge...

  3. Environmental restoration at the Pantex Plant. Quarterly progress report, April 12, 1995--June 30, 1995

    International Nuclear Information System (INIS)

    Charbeneau, R.J.

    1995-01-01

    This report summarizes the Work Plans for activities associated with Environmental Restoration of the perched aquifer and contaminated soils at the Pantex Plant. The Higher Education Consortium/Pantex Research Laboratory is participating in the Consortium Grant to evaluate subsurface remediation alternatives for the perched aquifer at the Pantex Plant. Research activities will develop site characterization data and evaluate remediation alternatives for the perched aquifer and the overlying vadose zone. The work plans cover research activities for the remainder of FY95, and proposed activities for FY96 and thereafter. A separate document will present more detailed plans for FY96 activities and budget requirements

  4. Rapid disease progression in human immunodeficiency virus type 1-infected individuals with adverse reactions to trimethoprim-sulfamethoxazole prophylaxis

    NARCIS (Netherlands)

    Veenstra, J.; Veugelers, P. J.; Keet, I. P.; van der Ven, A. J. A. M.; Miedema, F.; Lange, J. M.; Coutinho, R. A.

    1997-01-01

    We studied the relation between the occurrence of adverse reactions to trimethoprim-sulfamethoxazole (TMP-SMZ) prophylaxis and the subsequent course of human immunodeficiency virus (HIV) infection in a cohort of homosexual men. Adverse reactions to TMP-SMZ were associated with a more rapid

  5. Progress in Developing a High-Availability Advanced Tokamak Pilot Plant

    Energy Technology Data Exchange (ETDEWEB)

    Brown, T.; Goldston, R.; Kessel, C.; Neilson, G.; Menard, J.; Prager, S.; Scott, S.; Titus, P.; Zarnstorff, M., E-mail: tbrown@pppl.gov [Princeton University, Princeton Plasma Physics Laboratory, Princeton (United States); Costley, A. [Henley on Thames (United Kingdom); El-Guebaly, L. [University of Wisconsin, Madison (United States); Malang, S. [Fusion Nuclear Technology Consulting, Linkenheim (Germany); Waganer, L. [St. Louis (United States)

    2012-09-15

    Full text: A fusion pilot plant study was initiated to clarify the development needs in moving from ITER to a first of a kind fusion power plant, following a path similar to the approach adopted for the commercialization of fission. The mission of the pilot plant was set to encompass component test and fusion nuclear science missions yet produce net electricity with high availability in a device designed to be prototypical of the commercial device. The objective of the study was to evaluate three different magnetic configuration options, the advanced tokamak (AT), spherical tokamak (ST) and compact stellarator (CS) in an effort to establish component characteristics, maintenance features and the general arrangement of each candidate device. With the move to look beyond ITER the fusion community is now beginning to embark on DEMO reactor studies with an emphasis on defining configuration arrangements that can meet a high availability goal. In this paper the AT pilot plant design will be presented. The selected maintenance approach, the device arrangement and sizing of the in-vessel components and details of interfacing auxiliary systems and services that impact the ability to achieve high availability operations will be discussed. Efforts made to enhance the interaction of in-vessel maintenance activities, the hot cell and the transfer process to develop simplifying solutions will also be addressed. (author)

  6. Delays in nuclear power plant construction. Progress report, September 15, 1976--September 14, 1977

    International Nuclear Information System (INIS)

    Mason, G.E.; Larew, R.E.

    1977-01-01

    This report identifies barriers to shortening nuclear power plant construction schedules and recommends research efforts that should minimize or eliminate the identified barriers. The identified barriers include: (1) design and construction interfacing problems; (2) problems relating to the selection and use of permanent materials and construction methods; (3) construction coordination and communication problems; and (4) problems associated with manpower availability and productivity;

  7. Behavior of technetium-99 in soils and plants. Progress report, April 1, 1974--March 31, 1977

    International Nuclear Information System (INIS)

    Gast, R.G.; Landa, E.R.; Thorvig, L.J.

    1976-12-01

    Studies described in this report were aimed at establishing the magnitude and mechanisms of 99 Tc sorption by soils and uptake by plants. Results show that 99 Tc was sorbed from solution over a period of two to five weeks by 8 of 11 soils studied. The slow rate of sorption, the lack of sorption by low organic matter soils, the elimination of sorption following sterilization and increased sorption following addition of dextrose all point to a microbial role in the sorption process. However, it has not been established whether this is a direct or indirect role nor is it possible to clearly predict the conditions under which sorption will occur. Results of plant uptake studies show that 99 Tc can be taken up and translocated into the photosynthetic tissue of higher plants with concentrations in seeds being much less than in vegetative tissue. Technetium-99 was also shown to be toxic to plants at low concentrations and evidence suggests that this is a chemically rather than a radiologically induced toxicity. However, this remains to be completely resolved, as well as whether there is a threshold level of 99 Tc required before toxicity occurs

  8. Structural and Functional Diversity of Plant Virus 3′-Cap-Independent Translation Enhancers (3′-CITEs

    Directory of Open Access Journals (Sweden)

    Verónica Truniger

    2017-11-01

    Full Text Available Most of the positive-strand RNA plant viruses lack the 5′-cap and/or the poly(A-tail that act synergistically to stimulate canonical translation of cellular mRNAs. However, they have RNA elements in the 5′- or 3′-untranslated regions of their RNAs that are required for their cap-independent translation. Cap-independent translation enhancers (CITEs have been identified in the genomic 3′-end of viruses belonging to the family Tombusviridae and the genus Luteovirus. Seven classes of 3′-CITEs have been described to date based on their different RNA structures. They generally control the efficient formation of the translation initiation complex by varying mechanisms. Some 3′-CITEs bind eukaryotic translation initiation factors, others ribosomal subunits, bridging these to the 5′-end by different mechanisms, often long-distance RNA–RNA interactions. As previously proposed and recently found in one case in nature, 3′-CITEs are functionally independent elements that are transferable through recombination between viral genomes, leading to potential advantages for virus multiplication. In this review, the knowledge on 3′-CITEs and their functioning is updated. We also suggest that there is local structural conservation in the regions interacting with eIF4E of 3′-CITEs belonging to different classes.

  9. Structural and Functional Diversity of Plant Virus 3′-Cap-Independent Translation Enhancers (3′-CITEs)

    Science.gov (United States)

    Truniger, Verónica; Miras, Manuel; Aranda, Miguel A.

    2017-01-01

    Most of the positive-strand RNA plant viruses lack the 5′-cap and/or the poly(A)-tail that act synergistically to stimulate canonical translation of cellular mRNAs. However, they have RNA elements in the 5′- or 3′-untranslated regions of their RNAs that are required for their cap-independent translation. Cap-independent translation enhancers (CITEs) have been identified in the genomic 3′-end of viruses belonging to the family Tombusviridae and the genus Luteovirus. Seven classes of 3′-CITEs have been described to date based on their different RNA structures. They generally control the efficient formation of the translation initiation complex by varying mechanisms. Some 3′-CITEs bind eukaryotic translation initiation factors, others ribosomal subunits, bridging these to the 5′-end by different mechanisms, often long-distance RNA–RNA interactions. As previously proposed and recently found in one case in nature, 3′-CITEs are functionally independent elements that are transferable through recombination between viral genomes, leading to potential advantages for virus multiplication. In this review, the knowledge on 3′-CITEs and their functioning is updated. We also suggest that there is local structural conservation in the regions interacting with eIF4E of 3′-CITEs belonging to different classes. PMID:29238357

  10. Rapid differentiation of closely related isolates of two plant viruses by polymerase chain reaction and restriction fragment length polymorphism analysis.

    Science.gov (United States)

    Barbara, D J; Morton, A; Spence, N J; Miller, A

    1995-09-01

    Immunocapture reverse transcriptase-polymerase chain reaction (RT-PCR) followed by restriction fragment length polymorphism (RFLP) analysis of the product has been shown to be an effective procedure for discriminating serologically indistinguishable isolates of two plant viruses, raspberry bushy dwarf (RBDV) and zucchini yellow mosaic (ZYMV). For both viruses, only limited sequence information was available at the time of primer design, but most of the isolates which were tested could be amplified (the one exception being a serologically quite distinct isolate of ZYMV). Restriction endonucleases revealing diagnostic RFLPs were readily identified. Each of two isolates of ZYMV could be detected in the presence of the other and the relative proportions approximately quantified by visual estimation of the relative intensity of the appropriate bands. A range of isolates of different RBDV pathotypes were compared; isolates were grouped in ways that accorded with their known history. Computer analysis of the published sequence from which the primers had been derived showed the sequenced isolate to be identical with an isolate imported from the USSR. The PCR/RFLP procedure is rapid (it can be completed in less than 2 days), effective and will probably be generally applicable to distinguishing closely related virus isolates, even where little sequence information is available.

  11. Tomato Infection by Whitefly-Transmitted Circulative and Non-Circulative Viruses Induce Contrasting Changes in Plant Volatiles and Vector Behaviour.

    Science.gov (United States)

    Fereres, Alberto; Peñaflor, Maria Fernanda G V; Favaro, Carla F; Azevedo, Kamila E X; Landi, Carolina H; Maluta, Nathalie K P; Bento, José Mauricio S; Lopes, Joao R S

    2016-08-11

    Virus infection frequently modifies plant phenotypes, leading to changes in behaviour and performance of their insect vectors in a way that transmission is enhanced, although this may not always be the case. Here, we investigated Bemisia tabaci response to tomato plants infected by Tomato chlorosis virus (ToCV), a non-circulative-transmitted crinivirus, and Tomato severe rugose virus (ToSRV), a circulative-transmitted begomovirus. Moreover, we examined the role of visual and olfactory cues in host plant selection by both viruliferous and non-viruliferous B. tabaci. Visual cues alone were assessed as targets for whitefly landing by placing leaves underneath a Plexiglas plate. A dual-choice arena was used to assess whitefly response to virus-infected and mock-inoculated tomato leaves under light and dark conditions. Thereafter, we tested the whitefly response to volatiles using an active air-flow Y-tube olfactometer, and chemically characterized the blends using gas chromatography coupled to mass spectrometry. Visual stimuli tests showed that whiteflies, irrespective of their infectious status, always preferred to land on virus-infected rather than on mock-inoculated leaves. Furthermore, whiteflies had no preference for either virus-infected or mock-inoculated leaves under dark conditions, but preferred virus-infected leaves in the presence of light. ToSRV-infection promoted a sharp decline in the concentration of some tomato volatiles, while an increase in the emission of some terpenes after ToCV infection was found. ToSRV-viruliferous whiteflies preferred volatiles emitted from mock-inoculated plants, a conducive behaviour to enhance virus spread, while volatiles from ToCV-infected plants were avoided by non-viruliferous whiteflies, a behaviour that is likely detrimental to the secondary spread of the virus. In conclusion, the circulative persistent begomovirus, ToSRV, seems to have evolved together with its vector B. tabaci to optimise its own spread. However

  12. Tomato Infection by Whitefly-Transmitted Circulative and Non-Circulative Viruses Induce Contrasting Changes in Plant Volatiles and Vector Behaviour

    Directory of Open Access Journals (Sweden)

    Alberto Fereres

    2016-08-01

    Full Text Available Virus infection frequently modifies plant phenotypes, leading to changes in behaviour and performance of their insect vectors in a way that transmission is enhanced, although this may not always be the case. Here, we investigated Bemisia tabaci response to tomato plants infected by Tomato chlorosis virus (ToCV, a non-circulative-transmitted crinivirus, and Tomato severe rugose virus (ToSRV, a circulative-transmitted begomovirus. Moreover, we examined the role of visual and olfactory cues in host plant selection by both viruliferous and non-viruliferous B. tabaci. Visual cues alone were assessed as targets for whitefly landing by placing leaves underneath a Plexiglas plate. A dual-choice arena was used to assess whitefly response to virus-infected and mock-inoculated tomato leaves under light and dark conditions. Thereafter, we tested the whitefly response to volatiles using an active air-flow Y-tube olfactometer, and chemically characterized the blends using gas chromatography coupled to mass spectrometry. Visual stimuli tests showed that whiteflies, irrespective of their infectious status, always preferred to land on virus-infected rather than on mock-inoculated leaves. Furthermore, whiteflies had no preference for either virus-infected or mock-inoculated leaves under dark conditions, but preferred virus-infected leaves in the presence of light. ToSRV-infection promoted a sharp decline in the concentration of some tomato volatiles, while an increase in the emission of some terpenes after ToCV infection was found. ToSRV-viruliferous whiteflies preferred volatiles emitted from mock-inoculated plants, a conducive behaviour to enhance virus spread, while volatiles from ToCV-infected plants were avoided by non-viruliferous whiteflies, a behaviour that is likely detrimental to the secondary spread of the virus. In conclusion, the circulative persistent begomovirus, ToSRV, seems to have evolved together with its vector B. tabaci to optimise its own

  13. High throughput multiplex real time PCR assay for the simultaneous quantification of DNA and RNA viruses infecting cassava plants

    OpenAIRE

    Otti, Gerald; Bouvaine, Sophie; Kimata, Bernadetha; Mkamillo, Geoffrey; Kumar, Lava; Tomlins, Keith; Maruthi, M.N.

    2016-01-01

    Aims: To develop a multiplex TaqMan-based real-time PCR assay (qPCR) for the simultaneous detection and quantification of both RNA and DNA viruses affecting cassava (Manihot esculenta) in eastern Africa.\\ud \\ud Methods and Results: The diagnostic assay was developed for two RNA viruses; Cassava brown streak virus (CBSV) and Uganda cassava brown streak virus (UCBSV) and two predominant DNA viruses; African cassava mosaic virus (ACMV) and East African cassava mosaic virus (EACMV), which cause t...

  14. Studies regarding the effects of Rosmarinus officinalis oil treatments in healthy and potato virus Y (PVY infected plants Solanum tuberosum L.

    Directory of Open Access Journals (Sweden)

    Carmen Liliana BĂDĂRĂU

    2010-11-01

    Full Text Available The potato virus Y cause loss in yield and quality of tubers. Hydrogen peroxide, ascorbic acid and antioxidants such as rosmarinic acid present in oils extracted from Rosmarinus officinalis plants are implicated in signaling against stress. The effects of these chemicals on tuber yield and pigments content were evaluated in plants testing positive after virus mechanical infection. Without chemical treatment, positive plants showed significant reductions in leaf pigments content and tuber weights compared to uninfected controls. Hydrogen peroxide, ascorbic acid and oil treatments of PVY infected plants significantly reduced the number of minitubers, enhancing their weights, while leaf pigment content also increased. This research demonstrates potential benefits of treatments with oils extracted from Rosmarinus officinalis plants and hydrogen peroxide or ascorbic acid in enhancing the yield and quality of tubers.

  15. Integration of Plant Metabolomics Data with Metabolic Networks: Progresses and Challenges.

    Science.gov (United States)

    Töpfer, Nadine; Seaver, Samuel M D; Aharoni, Asaph

    2018-01-01

    In the last decade, plant genome-scale modeling has developed rapidly and modeling efforts have advanced from representing metabolic behavior of plant heterotrophic cell suspensions to studying the complex interplay of cell types, tissues, and organs. A crucial driving force for such developments is the availability and integration of "omics" data (e.g., transcriptomics, proteomics, and metabolomics) which enable the reconstruction, extraction, and application of context-specific metabolic networks. In this chapter, we demonstrate a workflow to integrate gas chromatography coupled to mass spectrometry (GC-MS)-based metabolomics data of tomato fruit pericarp (flesh) tissue, at five developmental stages, with a genome-scale reconstruction of tomato metabolism. This method allows for the extraction of context-specific networks reflecting changing activities of metabolic pathways throughout fruit development and maturation.

  16. Synaptotagmin SYTA forms ER-plasma membrane junctions that are recruited to plasmodesmata for plant virus movement.

    Science.gov (United States)

    Levy, Amit; Zheng, Judy Y; Lazarowitz, Sondra G

    2015-08-03

    Metazoan synaptotagmins are Ca(2+) sensors that regulate exocytosis and endocytosis in various cell types, notably in nerve and neuroendocrine cells [1, 2]. Recently, the structurally related extended synaptotagmins were shown to tether the cortical ER to the plasma membrane in human and yeast cells to maintain ER morphology and stabilize ER-plasma membrane (ER-PM) contact sites for intracellular lipid and Ca(2+) signaling [3, 4]. The Arabidopsis synaptotagmin SYTA regulates endocytosis and the ability of plant virus movement proteins (MPs) to alter plasmodesmata to promote virus cell-to-cell transport [5, 6]. Yet how MPs modify plasmodesmata, the cellular functions of SYTA and how these aid MP activity, and the proteins essential to form plant cell ER-PM contact sites remain unknown. We addressed these questions using an Arabidopsis SYTA knockdown line syta-1 and a Tobamovirus movement protein MP(TVCV) [5, 7]. We report here that SYTA localized to ER-PM contact sites. These sites were depleted and the ER network collapsed in syta-1, and both reformed upon rescue with SYTA. MP(TVCV) accumulation in plasmodesmata, but not secretory trafficking, was also inhibited in syta-1. During infection, MP(TVCV) recruited SYTA to plasmodesmata, and SYTA and the cortical ER were subsequently remodeled to form viral replication sites adjacent to plasmodesmata in which MP(TVCV) and SYTA directly interacted caged within ER membrane. SYTA also accumulated in plasmodesmata active in MP(TVCV) transport. Our findings show that SYTA is essential to form ER-PM contact sites and suggest that MPs interact with SYTA to recruit these sites to alter plasmodesmata for virus cell-to-cell movement. Copyright © 2015 Elsevier Ltd. All rights reserved.

  17. The RXL motif of the African cassava mosaic virus Rep protein is necessary for rereplication of yeast DNA and viral infection in plants

    Energy Technology Data Exchange (ETDEWEB)

    Hipp, Katharina; Rau, Peter; Schäfer, Benjamin [Institut für Biomaterialien und biomolekulare Systeme, Abteilung für Molekularbiologie und Virologie der Pflanzen, Universität Stuttgart, Pfaffenwaldring 57, D-70550 Stuttgart (Germany); Gronenborn, Bruno [Institut des Sciences du Végétal, CNRS, 91198 Gif-sur-Yvette (France); Jeske, Holger, E-mail: holger.jeske@bio.uni-stuttgart.de [Institut für Biomaterialien und biomolekulare Systeme, Abteilung für Molekularbiologie und Virologie der Pflanzen, Universität Stuttgart, Pfaffenwaldring 57, D-70550 Stuttgart (Germany)

    2014-08-15

    Geminiviruses, single-stranded DNA plant viruses, encode a replication-initiator protein (Rep) that is indispensable for virus replication. A potential cyclin interaction motif (RXL) in the sequence of African cassava mosaic virus Rep may be an alternative link to cell cycle controls to the known interaction with plant homologs of retinoblastoma protein (pRBR). Mutation of this motif abrogated rereplication in fission yeast induced by expression of wildtype Rep suggesting that Rep interacts via its RXL motif with one or several yeast proteins. The RXL motif is essential for viral infection of Nicotiana benthamiana plants, since mutation of this motif in infectious clones prevented any symptomatic infection. The cell-cycle link (Clink) protein of a nanovirus (faba bean necrotic yellows virus) was investigated that activates the cell cycle by binding via its LXCXE motif to pRBR. Expression of wildtype Clink and a Clink mutant deficient in pRBR-binding did not trigger rereplication in fission yeast. - Highlights: • A potential cyclin interaction motif is conserved in geminivirus Rep proteins. • In ACMV Rep, this motif (RXL) is essential for rereplication of fission yeast DNA. • Mutating RXL abrogated viral infection completely in Nicotiana benthamiana. • Expression of a nanovirus Clink protein in yeast did not induce rereplication. • Plant viruses may have evolved multiple routes to exploit host DNA synthesis.

  18. The RXL motif of the African cassava mosaic virus Rep protein is necessary for rereplication of yeast DNA and viral infection in plants

    International Nuclear Information System (INIS)

    Hipp, Katharina; Rau, Peter; Schäfer, Benjamin; Gronenborn, Bruno; Jeske, Holger

    2014-01-01

    Geminiviruses, single-stranded DNA plant viruses, encode a replication-initiator protein (Rep) that is indispensable for virus replication. A potential cyclin interaction motif (RXL) in the sequence of African cassava mosaic virus Rep may be an alternative link to cell cycle controls to the known interaction with plant homologs of retinoblastoma protein (pRBR). Mutation of this motif abrogated rereplication in fission yeast induced by expression of wildtype Rep suggesting that Rep interacts via its RXL motif with one or several yeast proteins. The RXL motif is essential for viral infection of Nicotiana benthamiana plants, since mutation of this motif in infectious clones prevented any symptomatic infection. The cell-cycle link (Clink) protein of a nanovirus (faba bean necrotic yellows virus) was investigated that activates the cell cycle by binding via its LXCXE motif to pRBR. Expression of wildtype Clink and a Clink mutant deficient in pRBR-binding did not trigger rereplication in fission yeast. - Highlights: • A potential cyclin interaction motif is conserved in geminivirus Rep proteins. • In ACMV Rep, this motif (RXL) is essential for rereplication of fission yeast DNA. • Mutating RXL abrogated viral infection completely in Nicotiana benthamiana. • Expression of a nanovirus Clink protein in yeast did not induce rereplication. • Plant viruses may have evolved multiple routes to exploit host DNA synthesis

  19. The plant virus microscope image registration method based on mismatches removing.

    Science.gov (United States)

    Wei, Lifang; Zhou, Shucheng; Dong, Heng; Mao, Qianzhuo; Lin, Jiaxiang; Chen, Riqing

    2016-01-01

    The electron microscopy is one of the major means to observe the virus. The view of virus microscope images is limited by making specimen and the size of the camera's view field. To solve this problem, the virus sample is produced into multi-slice for information fusion and image registration techniques are applied to obtain large field and whole sections. Image registration techniques have been developed in the past decades for increasing the camera's field of view. Nevertheless, these approaches typically work in batch mode and rely on motorized microscopes. Alternatively, the methods are conceived just to provide visually pleasant registration for high overlap ratio image sequence. This work presents a method for virus microscope image registration acquired with detailed visual information and subpixel accuracy, even when overlap ratio of image sequence is 10% or less. The method proposed focus on the correspondence set and interimage transformation. A mismatch removal strategy is proposed by the spatial consistency and the components of keypoint to enrich the correspondence set. And the translation model parameter as well as tonal inhomogeneities is corrected by the hierarchical estimation and model select. In the experiments performed, we tested different registration approaches and virus images, confirming that the translation model is not always stationary, despite the fact that the images of the sample come from the same sequence. The mismatch removal strategy makes building registration of virus microscope images at subpixel accuracy easier and optional parameters for building registration according to the hierarchical estimation and model select strategies make the proposed method high precision and reliable for low overlap ratio image sequence. Copyright © 2015 Elsevier Ltd. All rights reserved.

  20. Plant-Derived Anti-Inflammatory Compounds: Hopes and Disappointments regarding the Translation of Preclinical Knowledge into Clinical Progress

    Directory of Open Access Journals (Sweden)

    Robert Fürst

    2014-01-01

    Full Text Available Many diseases have been described to be associated with inflammatory processes. The currently available anti-inflammatory drug therapy is often not successful or causes intolerable side effects. Thus, new anti-inflammatory substances are still urgently needed. Plants were the first source of remedies in the history of mankind. Since their chemical characterization in the 19th century, herbal bioactive compounds have fueled drug development. Also, nowadays, new plant-derived agents continuously enrich our drug arsenal (e.g., vincristine, galantamine, and artemisinin. The number of new, pharmacologically active herbal ingredients, in particular that of anti-inflammatory compounds, rises continuously. The major obstacle in this field is the translation of preclinical knowledge into evidence-based clinical progress. Human trials of good quality are often missing or, when available, are frequently not suitable to really prove a therapeutical value. This minireview will summarize the current situation of 6 very prominent plant-derived anti-inflammatory compounds: curcumin, colchicine, resveratrol, capsaicin, epigallocatechin-3-gallate (EGCG, and quercetin. We will highlight their clinical potential and/or pinpoint an overestimation. Moreover, we will sum up the planned trials in order to provide insights into the inflammatory disorders that are hypothesized to be beneficially influenced by the compound.

  1. Complete suppression of viral gene expression is associated with the onset and progression of lymphoid malignancy: observations in Bovine Leukemia Virus-infected sheep

    Directory of Open Access Journals (Sweden)

    Burny Arsène

    2007-07-01

    Full Text Available Abstract Background During malignant progression, tumor cells need to acquire novel characteristics that lead to uncontrolled growth and reduced immunogenicity. In the Bovine Leukemia Virus-induced ovine leukemia model, silencing of viral gene expression has been proposed as a mechanism leading to immune evasion. However, whether proviral expression in tumors is completely suppressed in vivo was not conclusively demonstrated. Therefore, we studied viral expression in two selected experimentally-infected sheep, the virus or the disease of which had features that made it possible to distinguish tumor cells from their nontransformed counterparts. Results In the first animal, we observed the emergence of a genetically modified provirus simultaneously with leukemia onset. We found a Tax-mutated (TaxK303 replication-deficient provirus in the malignant B-cell clone while functional provirus (TaxE303 had been consistently monitored over the 17-month aleukemic period. In the second case, both non-transformed and transformed BLV-infected cells were present at the same time, but at distinct sites. While there was potentially-active provirus in the non-leukemic blood B-cell population, as demonstrated by ex-vivo culture and injection into naïve sheep, virus expression was completely suppressed in the malignant B-cells isolated from the lymphoid tumors despite the absence of genetic alterations in the proviral genome. These observations suggest that silencing of viral genes, including the oncoprotein Tax, is associated with tumor onset. Conclusion Our findings suggest that silencing is critical for tumor progression and identify two distinct mechanisms-genetic and epigenetic-involved in the complete suppression of virus and Tax expression. We demonstrate that, in contrast to systems that require sustained oncogene expression, the major viral transforming protein Tax can be turned-off without reversing the transformed phenotype. We propose that suppression

  2. Progress and experiences from the decommissioning of the Eurochemic reprocessing plant

    International Nuclear Information System (INIS)

    Gills, R.; Lewandowski, P.; Ooms, B.; Reusen, N.; Van Laer, W.; Walthery, R.

    2007-01-01

    Belgoprocess started the industrial decommissioning of the main process building of the former EUROCHEMIC reprocessing plant in 1990, after completion of a pilot project in which two buildings were emptied and decontaminated to background levels. The remaining structures were demolished and the concrete debris was disposed of as industrial waste and green field conditions restored. The Eurochemic reprocessing plant operated from 1966 to 1974 to process fuel from power reactors and research reactors. The main building is a large concrete structure, comprising a surface area of 55,000 m 2 , concrete volume 12,500 m 3 , and 1,500 Mg of metal components. The building is divided into multiple cells. About 106 individual cell structures have to be dismantled, involving the removal and decontamination of equipment from each cell, the decontamination of the cell walls, ceilings and floors, the dismantling of the ventilation system. Most of the work involves hands-on operations under protective clothing tailored to each specific task. Tool automation and automatic positioning systems are successfully applied. In view of the final demolition of the main process building, the main process building is divided into three parts - each part is isolated from the others. In the middle of 2008, after the removal of the NDA-IPAN/GEA installation, the eastern part will be demolished. The paper presents a status overview of the decommissioning and decontamination activities at the main process building of the former Eurochemic reprocessing plant on the nuclear site of Dessel in Belgium. The specific BELGOPROCESS approach will be highlighted, in which the decommissioning activities are carried out on an industrial scale with special emphasis on cost minimisation, the use of technology on an industrial representative scale and the specific alpha contamination of equipment and building surfaces, requiring that the decommissioning work is done with adequate protective clothing. Also

  3. Progress and experiences from the decommissioning of the Eurochemic reprocessing plant - 16022

    International Nuclear Information System (INIS)

    Walthery, Robert; Lewandowski, Patrick; Ooms, Bart; Reusen, Nancy; Van Laer, Wim

    2009-01-01

    Belgoprocess started the industrial decommissioning of the main process building of the former EUROCHEMIC reprocessing plant in 1990, after completion of a pilot project in which two buildings were emptied and decontaminated to background levels. The remaining structures were demolished and the concrete debris was disposed of as industrial waste and green field conditions restored. The Eurochemic reprocessing plant operated from 1966 to 1974 to process fuel from power reactors and research reactors. The main building is a large concrete structure, comprising a surface area of 55,000 m 2 , concrete volume 12,500 m 3 , and 1,500 Mg of metal components. The building is divided into multiple cells. About 106 individual cell structures have to be dismantled, involving the removal and decontamination of equipment from each cell, the decontamination of the cell walls, ceilings and floors, the dismantling of the ventilation system. Most of the work involves hands-on operations under protective clothing tailored to each specific task. Tool automation and automatic positioning systems are successfully applied. In view of the final demolition of the main process building, the main process building has been divided into three parts - each part is isolated from the others. In September 2008 the eastern part of the building has been demolished. The paper presents a status overview of the decommissioning and decontamination activities at the main process building of the former Eurochemic reprocessing plant on the nuclear site of Dessel in Belgium. The specific BELGOPROCESS strategy will be highlighted, in which the decommissioning activities are carried out on an industrial scale with special emphasis on cost minimisation, the use of technology on an industrial representative scale and the specific alpha contamination of equipment and building surfaces, requiring that the decommissioning work is done with adequate protective clothing. Also specific breathing and cooling air

  4. Atmospheric dispersion modeling at the Rocky Flats Plant. Progress report, December 1981-December 1985

    International Nuclear Information System (INIS)

    Hodgin, C.R.

    1986-01-01

    The Rocky Flats Plant applies atmospheric dispersion modeling as a tool for Emergency Response, Risk Assessment, and Regulatory Compliance. Extreme variations in terrain around the facility have necessitated the development of an advanced modeling approach. The Terrain-Responsive Atmospheric Code (TRAC) was developed to treat realistically the changing wind, stability, dispersion, and deposition patterns that are experienced in mountainous areas. The result is a detailed picture of dose and deposition patterns associated with postulated or actual releases. A unified approach was taken to modeling needs at Rocky Flats. This produces consistent dose projections for all applications. A Risk Assessment version of TRAC is now operational. A high-speed version of the code is being implemented for Emergency Response, and development of a regulatory version is under way. Public, scientific, and governmental acceptance of TRAC is critical to successful applications at the Rocky Flats Plant. A program of peer review and regulatory approval was initiated to provide a full outside evaluation of our techniques. Full field validation (tracer testing) is key to demonstrating reliability of the TRAC model. A validation study was planned for implementation beginning in early CY-1986. The necessary funding ($500,000) is being sought. Although the TRAC model development and approval program was developed for site-specific needs at the Rocky Flats Plant, potential exists for wider application within the Department of Energy (DOE). The TRAC model can be easily applied at other sites in complex terrain. A coordinated approach to model validation throughout the Albquerque Operations Office (AL) or DOE complexes could prove more cost effective than site-by-site evaluations. Finally, the model approval procedure developed jointly by Rocky Flats and the Environmental Protection Agency (EPA) is general and could be applied to other models or as the basis for a DOE-wide program

  5. Progress and experiences from the decommissioning of the eurochemic reprocessing plant

    International Nuclear Information System (INIS)

    Gillis, R.; Lewandowski, P.; Ooms, B.; Reusen, N.; Van Laer, W.; Walthery, R.

    2008-01-01

    The Eurochemic reprocessing facility at Dessel in Belgium, was constructed from 1960 to 1966. After shutdown, the plant was decontaminated from 1975 to 1979 to keep safe standby conditions at reasonable cost. When it was decided in 1986 not to resume reprocessing in Belgium, the main Belgoprocess activities changed to processing and storage of radioactive waste and to decontamination and decommissioning of obsolete nuclear facilities. The industrial decommissioning was started in 1990. This document presents the project: overview of decommissioning activities and equipment used, automation in decontamination, ensuring health and safety during the operations, release of decontaminated materials, current situation of the decommissioning activities and quality assurance program. (A.L.B.)

  6. Instrumentation and process control for fossil demonstration plants. Quarterly technical progress report, April--June 1977

    Energy Technology Data Exchange (ETDEWEB)

    LeSage, L.G.

    1977-07-01

    Work has been performed on updating the study of the state-of-the-art of instrumentation for Fossil Demonstration Plants (FDP), development of mass-flow and other on-line instruments for FDP, process control analysis for FDP, and organization of a symposium on instrumentation and control for FDP. A Solids/Gas Flow Test Facility (S/GFTF) under construction for instrument development, testing, evaluation, and calibration is described. The development work for several mass-flow and other on-line instruments is described: acoustic flowmeter, capacitive density flowmeter, neutron activation flowmeter and composition analysis system, gamma ray correlation flowmeter, optical flowmeter, and capacitive liquid interface level meter.

  7. Chemical effluents in surface waters from nuclear power plants. Quarterly progress report

    International Nuclear Information System (INIS)

    Harrison, F.L.

    1978-01-01

    The objectives of this research project are threefold: to obtain data on the behavior of potentially toxic substances introduced into surface waters from nuclear power plants; to determine the magnitude of the impact of these substances on representative and economically important aquatic species; and to develop models with which to predict the partitioning of these substances among the abiotic aquatic compartments. To fulfill these objectives in our investigation of copper, we are determining copper partitioning in marine and freshwater systems, evaluating the toxicity of copper to representative aquatic organisms, and developing a mathematical model to predict copper partitioning

  8. A new application of plant virus nanoparticles as drug delivery in breast cancer

    DEFF Research Database (Denmark)

    Esfandiari, Neda; Arzanani, Mohsen Karimi; Soleimani, Masoud

    2016-01-01

    used nanoparticles formed from the potato virus X to conjugate the Herceptin (Trastuzumab) monoclonal antibody as a new option in specific targeting of breast cancer. Bioconjugation was performed by EDC/sulfo-n-hydroxysuccinimide (sulfo-NHS) in a two-step protocol. Then, the efficiency of conjugation...

  9. 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 ...

  10. Maintenance of EDF nuclear power plants and servicing companies. Progress report

    International Nuclear Information System (INIS)

    Baize, Jean-Marc; Reveillon, Sylvie

    1997-01-01

    French Electricity Company (EDF - Electricite de France) and the associated servicing companies, engaged in maintenance partnership from 1991, reinforce and expand their policy by undersigning a progress charter, to cope with the safety and nuclear sector competition issues. This charter stipulates the mutual engagements in the following sectors: 1. Transparency in calling for servicing; 2. Development of the intervenors' professionalism; 3. Improvement in forecasting activity tasks; 4. Radioprotection; 5. Safety and working conditions. The 55 reactors of the EDF nuclear stock are stopped annually for around 6 weeks for refueling. On this occasion the essential maintenance works necessary to ensure the optimal safety of the installations are carried out. The maintenance requires the intervention of 30,000 employees, 10,000 EDF agents and 20,000 external intervenors and represents an amount of 14 million working hours. The full maintenance expenses amounts up to 11 billion FF in 1996, 6 billion of which are assigned to external companies

  11. Virus-Induced Silencing of Key Genes Leads to Differential Impact on Withanolide Biosynthesis in the Medicinal Plant, Withania somnifera.

    Science.gov (United States)

    Agarwal, Aditya Vikram; Singh, Deeksha; Dhar, Yogeshwar Vikram; Michael, Rahul; Gupta, Parul; Chandra, Deepak; Trivedi, Prabodh Kumar

    2018-02-01

    Withanolides are a collection of naturally occurring, pharmacologically active, secondary metabolites synthesized in the medicinally important plant, Withania somnifera. These bioactive molecules are C28-steroidal lactone triterpenoids and their synthesis is proposed to take place via the mevalonate (MVA) and 2-C-methyl-d-erythritol-4-phosphate (MEP) pathways through the sterol pathway using 24-methylene cholesterol as substrate flux. Although the phytochemical profiles as well as pharmaceutical activities of Withania extracts have been well studied, limited genomic information and difficult genetic transformation have been a major bottleneck towards understanding the participation of specific genes in withanolide biosynthesis. In this study, we used the Tobacco rattle virus (TRV)-mediated virus-induced gene silencing (VIGS) approach to study the participation of key genes from MVA, MEP and triterpenoid biosynthesis for their involvement in withanolide biosynthesis. TRV-infected W. somnifera plants displayed unique phenotypic characteristics and differential accumulation of total Chl as well as carotenoid content for each silenced gene suggesting a reduction in overall isoprenoid synthesis. Comprehensive expression analysis of putative genes of withanolide biosynthesis revealed transcriptional modulations conferring the presence of complex regulatory mechanisms leading to withanolide biosynthesis. In addition, silencing of genes exhibited modulated total and specific withanolide accumulation at different levels as compared with control plants. Comparative analysis also suggests a major role for the MVA pathway as compared with the MEP pathway in providing substrate flux for withanolide biosynthesis. These results demonstrate that transcriptional regulation of selected Withania genes of the triterpenoid biosynthetic pathway critically affects withanolide biosynthesis, providing new horizons to explore this process further, in planta.

  12. 1997 Gordon Research Conference on Plant Cell Walls. Final progress report

    Energy Technology Data Exchange (ETDEWEB)

    Staehelin, A.

    1999-08-25

    The Gordon Research Conference (GRC) on Plant Cell Walls was held at Tilton School, Tilton, New Hampshire, July 18-22, 1997. The conference was well attended with 106 participants. The attendees represented the spectrum of endeavor in this field coming from academia, industry, and government laboratories, both US and foreign scientists, senior researchers, young investigators, and students. In designing the formal speakers program, emphasis was placed on current unpublished research and discussion of the future target areas in this field. There was a conscious effort to stimulate lively discussion about the key issues in the field today. Time for formal presentations was limited in the interest of group discussions. In order that more scientists could communicate their most recent results, poster presentation time was scheduled. In addition to these formal interactions, free time was scheduled to allow informal discussions. Such discussions are fostering new collaborations and joint efforts in the field.

  13. Progress in long-lived radioactive waste management and disposal at the waste isolation pilot plant

    Energy Technology Data Exchange (ETDEWEB)

    Triay, I R; Matthews, M L [U.S. Dept. of Energy Carlsbad Field Office, New Mexico (United States); Eriksson, L G [GRAM, Inc., Albuquerque, NM (United States)

    2001-07-01

    The Salado Formation is buried more than 350 m beneath the sands and cacti of the Chihuahuan Desert and hosts the Waste Isolation Pilot Plant (WIPP) deep geological repository at a depth of approximately 650 m. Since the WIPP repository is at least 10 years ahead of any other repository development for long-lived radioactive waste, other radioactive waste management organizations and institutions could benefit both scientifically and politically from sharing the lessons learned at WIPP. Benefits would include using existing expertise and facilities to cost-effectively address and solve program-specific issues and to train staff. The characteristics of the WIPP repository and infrastructure are described in this paper. (author)

  14. Progress in long-lived radioactive waste management and disposal at the waste isolation pilot plant

    International Nuclear Information System (INIS)

    Triay, I.R.; Matthews, M.L.; Eriksson, L.G.

    2001-01-01

    The Salado Formation is buried more than 350 m beneath the sands and cacti of the Chihuahuan Desert and hosts the Waste Isolation Pilot Plant (WIPP) deep geological repository at a depth of approximately 650 m. Since the WIPP repository is at least 10 years ahead of any other repository development for long-lived radioactive waste, other radioactive waste management organizations and institutions could benefit both scientifically and politically from sharing the lessons learned at WIPP. Benefits would include using existing expertise and facilities to cost-effectively address and solve program-specific issues and to train staff. The characteristics of the WIPP repository and infrastructure are described in this paper. (author)

  15. Zika virus infection, transmission, associated neurological disorders and birth abnormalities:A review of progress in research, priorities and knowledge gaps

    Institute of Scientific and Technical Information of China (English)

    Yitades Gebre; Nikkiah Forbes; Teshome Gebre

    2016-01-01

    On February 1, 2016, the World Health Organization declared that the cluster of microcephaly cases and other neurological disorders constitute public health emergency of international concern. Furthermore, few studies demonstrated that there was an increased evidence of causal relationship of Zika virus (ZIKAV) infection and micro-cephaly, birth abnormalities and neurological disorders such as Guillain–Barr ´e syndrome. ZIKAV transmission occurs mainly by the bite of infected mosquitos (Aedes species), but there are also reports that infections could occur via the placenta, breast milk, saliva, blood transfusion and sex. This article reviews the global efforts, progress in scientific research to understand the pathogenesis of ZIKAV infection & disease, clinical pre-sentations, congenital transmission and autoimmune neurological disorders. The paper further explores the knowledge gaps, future priority research agenda for strategic response including vector control and prevention. We conducted a systematic literature review to synthesise available evidence on ZIKAV infection and its vector and host interaction from electronic databases.

  16. HER2-Specific Chimeric Antigen Receptor-Modified Virus-Specific T Cells for Progressive Glioblastoma: A Phase 1 Dose-Escalation Trial.

    Science.gov (United States)

    Ahmed, Nabil; Brawley, Vita; Hegde, Meenakshi; Bielamowicz, Kevin; Kalra, Mamta; Landi, Daniel; Robertson, Catherine; Gray, Tara L; Diouf, Oumar; Wakefield, Amanda; Ghazi, Alexia; Gerken, Claudia; Yi, Zhongzhen; Ashoori, Aidin; Wu, Meng-Fen; Liu, Hao; Rooney, Cliona; Dotti, Gianpietro; Gee, Adrian; Su, Jack; Kew, Yvonne; Baskin, David; Zhang, Yi Jonathan; New, Pamela; Grilley, Bambi; Stojakovic, Milica; Hicks, John; Powell, Suzanne Z; Brenner, Malcolm K; Heslop, Helen E; Grossman, Robert; Wels, Winfried S; Gottschalk, Stephen

    2017-08-01

    Glioblastoma is an incurable tumor, and the therapeutic options for patients are limited. To determine whether the systemic administration of HER2-specific chimeric antigen receptor (CAR)-modified virus-specific T cells (VSTs) is safe and whether these cells have antiglioblastoma activity. In this open-label phase 1 dose-escalation study conducted at Baylor College of Medicine, Houston Methodist Hospital, and Texas Children's Hospital, patients with progressive HER2-positive glioblastoma were enrolled between July 25, 2011, and April 21, 2014. The duration of follow-up was 10 weeks to 29 months (median, 8 months). Monotherapy with autologous VSTs specific for cytomegalovirus, Epstein-Barr virus, or adenovirus and genetically modified to express HER2-CARs with a CD28.ζ-signaling endodomain (HER2-CAR VSTs). Primary end points were feasibility and safety. The key secondary end points were T-cell persistence and their antiglioblastoma activity. A total of 17 patients (8 females and 9 males; 10 patients ≥18 years [median age, 60 years; range, 30-69 years] and 7 patients VSTs (1 × 106/m2 to 1 × 108/m2) without prior lymphodepletion. Infusions were well tolerated, with no dose-limiting toxic effects. HER2-CAR VSTs were detected in the peripheral blood for up to 12 months after the infusion by quantitative real-time polymerase chain reaction. Of 16 evaluable patients (9 adults and 7 children), 1 had a partial response for more than 9 months, 7 had stable disease for 8 weeks to 29 months, and 8 progressed after T-cell infusion. Three patients with stable disease are alive without any evidence of progression during 24 to 29 months of follow-up. For the entire study cohort, median overall survival was 11.1 months (95% CI, 4.1-27.2 months) from the first T-cell infusion and 24.5 months (95% CI, 17.2-34.6 months) from diagnosis. Infusion of autologous HER2-CAR VSTs is safe and can be associated with clinical benefit for patients with progressive glioblastoma

  17. Characterization of viruses infecting potato plants from a single location in Shetland, an isolated scottish archipelago

    DEFF Research Database (Denmark)

    Mortensen, R.J.; Shen, Xinyi; Reid, Alex

    2010-01-01

    , as were 29 Scottish mainland isolates of the same four potato virus species, and these 58 isolates were compared to previously published sequence data. This has allowed the characterization of viruses from a relatively isolated location, where there is little production of ware potatoes and no seed potato...... production. Phylogenetic homogeneity of the Shetland isolates of PVS and PVV was apparent. PVX was more heterogeneous, and Shetland isolates cluster with the Scottish isolates in a group which includes Asian and European isolates. For PVA, the majority of the Shetland and Scottish mainland isolates formed...... a predominantly Scottish grouping, with the remaining Shetland and Scottish mainland isolates clustering with a previously characterized Scottish isolate. There were three main groups of PVA, of which the Scottish grouping was the only one which did not have a fully characterized representative. To extend...

  18. Effects of West Nile virus dose and extrinsic incubation temperature on temporal progression of vector competence in Culex pipiens quinquefasciatus.

    Science.gov (United States)

    Anderson, Sheri L; Richards, Stephanie L; Tabachnick, Walter J; Smartt, Chelsea T

    2010-03-01

    Culex pipiens quinquefasciatus were fed blood containing either 7.0 +/- 0.1 logs plaque-forming units (pfu)/ml (high dose) or 5.9 +/- 0.1 logs pfu/ml (low dose) of West Nile virus and held at extrinsic incubation temperatures (EIT) of 28 degrees C or 25 degrees C. Approximately 20 mosquitoes per dose were collected after incubation periods (IP) of 4, 6, 8, and 12 days postinfection (dpi). Infection rates were influenced by EIT and virus dose but not by IP. Body titer was significantly higher for mosquitoes fed the high dose and held at 28 degrees C at the later IPs (6, 8, and 12 dpi). However, leg titer was significantly higher for mosquitoes at the later IPs but did not differ between EITs or doses. Because infection rates varied with EIT and dose, there is likely a midgut infection barrier influenced by these factors that is not influenced by IP. Dissemination rates were influenced by all 3 factors consistent with the presence of a midgut escape barrier. Dissemination rate, body titer, and leg titer were dependent on IP, indicating the need to investigate multiple time points in vector competence studies to elucidate critical events in infection and dissemination.

  19. Genetic recombination in plant-infecting messenger-sense RNA viruses: overview and research perspectives

    Directory of Open Access Journals (Sweden)

    Jozef Julian Bujarski

    2013-03-01

    Full Text Available RNA recombination is one of the driving forces of genetic variability in (+-strand RNA viruses. Various types of RNA-RNA crossovers were described including crosses between the same or different viral RNAs or between viral and cellular RNAs. Likewise, a variety of molecular mechanisms are known to support RNA recombination, such as replicative events (based on internal or end-to-end replicase switchings along with nonreplicative joining among RNA fragments of viral and/or cellular origin. Such mechanisms as RNA decay or RNA interference are responsible for RNA fragmentation and trans-esterification reactions which are likely accountable for ligation of RNA fragments. Numerous host factors were found to affect the profiles of viral RNA recombinants and significant differences in recombination frequency were observed among various RNA viruses. Comparative analyses of viral sequences allowed for the development of evolutionary models in order to explain adaptive phenotypic changes and co-evolving sites. Many questions remain to be answered by forthcoming RNA recombination research. (i How various factors modulate the ability of viral replicase to switch templates, (ii What is the intracellular location of RNA-RNA template switchings, (iii Mechanisms and factors responsible for non-replicative RNA recombination, (iv Mechanisms of integration of RNA viral sequences with cellular genomic DNA, and (v What is the role of RNA splicing and ribozyme activity. From an evolutionary stand point, it is not known how RNA viruses parasitize new host species via recombination, nor is it obvious what the contribution of RNA recombination is among other RNA modification pathways. We do not understand why the frequency of RNA recombination varies so much among RNA viruses and the status of RNA recombination as a form of sex is not well documented.

  20. Genetic recombination in plant-infecting messenger-sense RNA viruses: overview and research perspectives.

    Science.gov (United States)

    Bujarski, Jozef J

    2013-01-01

    RNA recombination is one of the driving forces of genetic variability in (+)-strand RNA viruses. Various types of RNA-RNA crossovers were described including crosses between the same or different viral RNAs or between viral and cellular RNAs. Likewise, a variety of molecular mechanisms are known to support RNA recombination, such as replicative events (based on internal or end-to-end replicase switchings) along with non-replicative joining among RNA fragments of viral and/or cellular origin. Such mechanisms as RNA decay or RNA interference are responsible for RNA fragmentation and trans-esterification reactions which are likely accountable for ligation of RNA fragments. Numerous host factors were found to affect the profiles of viral RNA recombinants and significant differences in recombination frequency were observed among various RNA viruses. Comparative analyses of viral sequences allowed for the development of evolutionary models in order to explain adaptive phenotypic changes and co-evolving sites. Many questions remain to be answered by forthcoming RNA recombination research. (1) How various factors modulate the ability of viral replicase to switch templates, (2) What is the intracellular location of RNA-RNA template switchings, (3) Mechanisms and factors responsible for non-replicative RNA recombination, (4) Mechanisms of integration of RNA viral sequences with cellular genomic DNA, and (5) What is the role of RNA splicing and ribozyme activity. From an evolutionary stand point, it is not known how RNA viruses parasitize new host species via recombination, nor is it obvious what the contribution of RNA recombination is among other RNA modification pathways. We do not understand why the frequency of RNA recombination varies so much among RNA viruses and the status of RNA recombination as a form of sex is not well documented.

  1. Ion-channel genosensor for the detection of specific DNA sequences derived from Plum Pox Virus in plant extracts.

    Science.gov (United States)

    Malecka, Kamila; Michalczuk, Lech; Radecka, Hanna; Radecki, Jerzy

    2014-10-09

    A DNA biosensor for detection of specific oligonucleotides sequences of Plum Pox Virus (PPV) in plant extracts and buffer is proposed. The working principles of a genosensor are based on the ion-channel mechanism. The NH2-ssDNA probe was deposited onto a glassy carbon electrode surface to form an amide bond between the carboxyl group of oxidized electrode surface and amino group from ssDNA probe. The analytical signals generated as a result of hybridization were registered in Osteryoung square wave voltammetry in the presence of [Fe(CN)6]3-/4- as a redox marker. The 22-mer and 42-mer complementary ssDNA sequences derived from PPV and DNA samples from plants infected with PPV were used as targets. Similar detection limits of 2.4 pM (31.0 pg/mL) and 2.3 pM (29.5 pg/mL) in the concentration range 1-8 pM were observed in the presence of the 22-mer ssDNA and 42-mer complementary ssDNA sequences of PPV, respectively. The genosensor was capable of discriminating between samples consisting of extracts from healthy plants and leaf extracts from infected plants in the concentration range 10-50 pg/mL. The detection limit was 12.8 pg/mL. The genosensor displayed good selectivity and sensitivity. The 20-mer partially complementary DNA sequences with four complementary bases and DNA samples from healthy plants used as negative controls generated low signal.

  2. Interdisciplinary Research and Training Program in the Plant Sciences. Technical progress report, February 1, 1991--November 30, 1992

    Energy Technology Data Exchange (ETDEWEB)

    Wolk, C.P.

    1992-07-01

    Research on plants continued. Topics include: Molecular basis of symbiotic plant-microbe interations; enzymatic mechanisms and regulation of plant cell wall biosynthesis; molecular mechanisms that regulate the expression of genes in plants; resistance of plants to environmental stress; studies on hormone biosynthesis and action; plant cell wall proteins; interaction of nuclear and organelle genomes; sensor transduction in plants; molecular mechanisms of trafficking in the plant cell; regulation of lipid metabolism; molecular bases of plant disease resistance mechanisms; biochemical and molecular aspects of plant pathogenesis; developmental biology of nitrogen-fixing cyanobacteria; environmental control of plant development and its relation to plant hormones.

  3. Plant incident progress scenario analysis for nuclear emergency exercise of Fukui Pref. 2009

    International Nuclear Information System (INIS)

    Tatebe, Yasumasa; Yoshida, Yoshitaka; Minami, Noritoshi

    2010-01-01

    Severe accident scenario was analyzed to assist the nuclear emergency exercise of Fukui prefecture in 2009. The evaluation of the postulated disaster was evaluated based on analysis result, including the time of occurrence of specified events, response of the plant to the AM measures, etc. The evaluation results are as follows: (1) loss of core cooling took place about 7 hours after, abnormal leakage of fission products from containment vessel to the containment annulus started about 17 hours after and the disaster terminated about 46 hours after the initiation of the accident, (2) although multiple failures of the engineered safety system and failure of AM measures were postulated in the accident scenario, the integrity of the containment vessel could be maintained successfully for a long term, if the AM measures are taken to protect the containment vessel. (3) according to the evaluation of radiation dose rate during the emergency response assuming the operation of recirculation mode using containment spray A, the dose rate could be too high for the operators to work not only in the containment spray A area but also in the another containment spray heat exchanger and the residual heat removal system heat exchanger areas. (author)

  4. The Rocky Flats Plant Waste Stream and Residue Identification and Characterization Program (WSRIC): Progress and achievements

    International Nuclear Information System (INIS)

    Ideker, V.L.

    1994-01-01

    The Waste Stream and Residue Identification and Characterization (WSRIC) Program, as described in the WSRIC Program Description delineates the process knowledge used to identify and characterize currently-generated waste from approximately 5404 waste streams originating from 576 processes in 288 buildings at Rocky Flats Plant (RFP). Annual updates to the WSRIC documents are required by the Federal Facilities Compliance Agreement between the US Department of Energy, the Colorado Department of Health and the Environmental Protection Agency. Accurate determination and characterization of waste is a crucial component in RFP's waste management strategy to assure compliance with Resource Conservation and Recovery Act (RCRA) storage and treatment requirements, as well as disposal acceptance criteria. The WSRIC Program was rebaselined in September 1992, and serves as the linchpin for documenting process knowledge in RFP's RCRA operating record. Enhancements to the WSRIC include strengthening the waste characterization rationale, expanding WSRIC training for waste generators, and incorporating analytical information into the WSRIC building books. These enhancements will improve credibility with the regulators and increase waste generators' understanding of the basis for credible waste characterizations

  5. Advanced light water reactor plants System 80+trademark design certification program. Annual progress report, October 1, 1994 - September 30, 1995

    International Nuclear Information System (INIS)

    1998-01-01

    The purpose of this report is to provide the status of the progress that was made towards Design Certification of System 80+trademark during the US government's 1995 fiscal year. The System 80+ Advanced Light Water Reactor (ALWR) is a 3931 MW (1350 MWe) Pressurized Water Reactor (PWR). The design covers an essentially complete plant. It is based on EPRI ALWR Utility Requirements Document (URD) improvements to the Standardized System 80 Nuclear Steam Supply System (NSSS) in operation at Palo Verde Units 1, 2, and 3. The NSSS is a traditional two-loop arrangement with two steam generators, two hot legs and four cold legs, each with a reactor coolant pump. The System 80+ standard design houses the NSSS in a spherical steel containment vessel which is enclosed in a concrete shield building, thus providing the safety advantages of a dual barrier to radioactivity release. Other major features include an all-digital, human-factors-engineered control room, an alternate electrical AC power source, an In-Containment Refueling Water Storage Tank (IRWST), and plant arrangements providing complete separation of redundant trains in safety systems

  6. Advanced light water reactor plants System 80+{trademark} design certification program. Annual progress report, October 1, 1994--September 30, 1995

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-09-01

    The purpose of this report is to provide the status of the progress that was made towards Design Certification of System 80+{trademark} during the US government`s 1995 fiscal year. The System 80+ Advanced Light Water Reactor (ALWR) is a 3931 MW (1350 MWe) Pressurized Water Reactor (PWR). The design covers an essentially complete plant. It is based on EPRI ALWR Utility Requirements Document (URD) improvements to the Standardized System 80 Nuclear Steam Supply System (NSSS) in operation at Palo Verde Units 1, 2, and 3. The NSSS is a traditional two-loop arrangement with two steam generators, two hot legs and four cold legs, each with a reactor coolant pump. The System 80+ standard design houses the NSSS in a spherical steel containment vessel which is enclosed in a concrete shield building, thus providing the safety advantages of a dual barrier to radioactivity release. Other major features include an all-digital, human-factors-engineered control room, an alternate electrical AC power source, an In-Containment Refueling Water Storage Tank (IRWST), and plant arrangements providing complete separation of redundant trains in safety systems.

  7. Advanced light water reactor plants System 80+trademark design certification program. Annual progress report, October 1, 1995 - September 30, 1996

    International Nuclear Information System (INIS)

    1996-01-01

    The purpose of this report is to provide a status of the progress that was made towards Design Certification of System 80+trademark during the US government's 1996 fiscal year. The System 80+ Advanced Light Water Reactor (ALWR) is a 3931 MW (1350 MWe) Pressurized Water Reactor (PWR). The design covers an essentially complete plant. It is based on EPRI ALWR Utility Requirements Document (URD) improvements to the Standardized System 80 Nuclear Steam Supply System (NSSS) in operation at Palo Verde Units 1, 2 and 3. The NSSS is a traditional two-loop arrangement with two steam generators, two hot legs and four cold legs, each with a reactor coolant pump. The System 80+ standard design houses the NSSS in a spherical steel containment vessel which is enclosed in a concrete shield building, thus providing the safety advantages of a dual barrier to radioactivity release. Other major features include an all-digital, human-factors-engineered control room, an alternate electrical AC power source, an In-Containment Refueling Water Storage Tank (IRWST), and plant arrangements providing complete separation of redundant trains in safety systems

  8. Insights into the Impact of CD8+ Immune Modulation on Human Immunodeficiency Virus Evolutionary Dynamics in Distinct Anatomical Compartments by Using Simian Immunodeficiency Virus-Infected Macaque Models of AIDS Progression.

    Science.gov (United States)

    Rife Magalis, Brittany; Nolan, David J; Autissier, Patrick; Burdo, Tricia H; Williams, Kenneth C; Salemi, Marco

    2017-12-01

    A thorough understanding of the role of human immunodeficiency virus (HIV) intrahost evolution in AIDS pathogenesis has been limited by the need for longitudinally sampled viral sequences from the vast target space within the host, which are often difficult to obtain from human subjects. CD8 + lymphocyte-depleted macaques infected with simian immunodeficiency virus (SIV) provide an increasingly utilized model of pathogenesis due to clinical manifestations similar to those for HIV-1 infection and AIDS progression, as well as a characteristic rapid disease onset. Comparison of this model with SIV-infected non-CD8 + lymphocyte-depleted macaques also provides a unique opportunity to investigate the role of CD8 + cells in viral evolution and population dynamics throughout the duration of infection. Using several different phylogenetic methods, we analyzed viral gp120 sequences obtained from extensive longitudinal sampling of multiple tissues and enriched leukocyte populations from SIVmac251-infected macaques with or without CD8 + lymphocyte depletion. SIV evolutionary and selection patterns in non-CD8 + lymphocyte-depleted animals were characterized by sequential population turnover and continual viral adaptation, a scenario readily comparable to intrahost evolutionary patterns during human HIV infection in the absence of antiretroviral therapy. Alternatively, animals that were depleted of CD8 + lymphocytes exhibited greater variation in population dynamics among tissues and cell populations over the course of infection. Our findings highlight the major role for CD8 + lymphocytes in prolonging disease progression through continual control of SIV subpopulations from various anatomical compartments and the potential for greater independent viral evolutionary behavior among these compartments in response to immune modulation. IMPORTANCE Although developments in combined antiretroviral therapy (cART) strategies have successfully prolonged the time to AIDS onset in HIV-1

  9. Plant rhizosphere effects on metal mobilization and transport. 1997 annual progress report

    International Nuclear Information System (INIS)

    Crowley, D.E.; Fan, T.W.M.; Higashi, R.M.

    1997-01-01

    'During the funding period of 1996--1997, the authors explored the utility of multi-nuclear, two-dimensional nuclear magnetic resonance (NMR) spectroscopy and gas chromatography-mass spectrometry (GC-MS) for a comprehensive analysis of barley root exudates collected under Fe sufficient and deficient conditions. As both structural and quantitative information was obtained directly from crude root exudates using this approach, no tedious sample fractionation was necessary, which will greatly facilitate future chemical characterization of root exudates in general. They found that the phytosiderophore mugineic acids (including 2'-deoxymugineic acid, mugineic acid, and 3-epi-hydroxymugineic acid) were readily identified and quantified in crude exudate samples along with a number of amino and organic acids. The amount of mugineic acids excreted was correlated positively with the extent of Fe deficiency with 3-epi-hydroxymugineic acid being the most prominent component. The total Fe chelating capacity was also measured using the ferrozine assay and compared with the production of the mugineic acids. They were surprised to find that the mugineic acids may account for a part of the Fe chelating capacity, especially under mild and moderatley Fe deficient conditions. Lactate, alanine, y-aminobutyrate, malate, and glycinebetaine collectively may contribute to a significant fraction of the Fe chelating capacity. In light of the known stimulatory effect of alanine and citrate on metal availability to algae (Campell, 1995), the function of these low molecular weight metabolites as vehicles for Fe or metal uptake in general warrant further investigation. This work is now published in Analytical Biochemistry 251, 57-68 ( 1997). They then proceeded to apply the above approach to investigate the interaction of elevated cadmium (Cd) with Fe deficiency in gramineous plants. They have completed one each series of cadmium (Cd) treatments of barley and wheat seedlings under Fe sufficient

  10. Phylogenetic relationships in Epidendroideae (Orchidaceae), one of the great flowering plant radiations: progressive specialization and diversification.

    Science.gov (United States)

    Freudenstein, John V; Chase, Mark W

    2015-03-01

    The largest subfamily of orchids, Epidendroideae, represents one of the most significant diversifications among flowering plants in terms of pollination strategy, vegetative adaptation and number of species. Although many groups in the subfamily have been resolved, significant relationships in the tree remain unclear, limiting conclusions about diversification and creating uncertainty in the classification. This study brings together DNA sequences from nuclear, plastid and mitochrondrial genomes in order to clarify relationships, to test associations of key characters with diversification and to improve the classification. Sequences from seven loci were concatenated in a supermatrix analysis for 312 genera representing most of epidendroid diversity. Maximum-likelihood and parsimony analyses were performed on this matrix and on subsets of the data to generate trees and to investigate the effect of missing values. Statistical character-associated diversification analyses were performed. Likelihood and parsimony analyses yielded highly resolved trees that are in strong agreement and show significant support for many key clades. Many previously proposed relationships among tribes and subtribes are supported, and some new relationships are revealed. Analyses of subsets of the data suggest that the relatively high number of missing data for the full analysis is not problematic. Diversification analyses show that epiphytism is most strongly associated with diversification among epidendroids, followed by expansion into the New World and anther characters that are involved with pollinator specificity, namely early anther inflexion, cellular pollinium stalks and the superposed pollinium arrangement. All tested characters show significant association with speciation in Epidendroideae, suggesting that no single character accounts for the success of this group. Rather, it appears that a succession of key features appeared that have contributed to diversification, sometimes in

  11. Characterization of the RNA silencing suppression activity of the Ebola virus VP35 protein in plants and mammalian cells.

    Science.gov (United States)

    Zhu, Yali; Cherukuri, Nil Celebi; Jackel, Jamie N; Wu, Zetang; Crary, Monica; Buckley, Kenneth J; Bisaro, David M; Parris, Deborah S

    2012-03-01

    Ebola virus (EBOV) causes a lethal hemorrhagic fever for which there is no approved effective treatment or prevention strategy. EBOV VP35 is a virulence factor that blocks innate antiviral host responses, including the induction of and response to alpha/beta interferon. VP35 is also an RNA silencing suppressor (RSS). By inhibiting microRNA-directed silencing, mammalian virus RSSs have the capacity to alter the cellular environment to benefit replication. A reporter gene containing specific microRNA target sequences was used to demonstrate that prior expression of wild-type VP35 was able to block establishment of microRNA silencing in mammalian cells. In addition, wild-type VP35 C-terminal domain (CTD) protein fusions were shown to bind small interfering RNA (siRNA). Analysis of mutant proteins demonstrated that reporter activity in RSS assays did not correlate with their ability to antagonize double-stranded RNA (dsRNA)-activated protein kinase R (PKR) or bind siRNA. The results suggest that enhanced reporter activity in the presence of VP35 is a composite of nonspecific translational enhancement and silencing suppression. Moreover, most of the specific RSS activity in mammalian cells is RNA binding independent, consistent with VP35's proposed role in sequestering one or more silencing complex proteins. To examine RSS activity in a system without interferon, VP35 was tested in well-characterized plant silencing suppression assays. VP35 was shown to possess potent plant RSS activity, and the activities of mutant proteins correlated strongly, but not exclusively, with RNA binding ability. The results suggest the importance of VP35-protein interactions in blocking silencing in a system (mammalian) that cannot amplify dsRNA.

  12. Mutational analyses of molecularly cloned satellite tobacco mosaic virus during serial passage in plants: Evidence for hotspots of genetic change

    Science.gov (United States)

    Kurath, G.; Dodds, J.A.

    1995-01-01

    The high level of genetic diversity and rapid evolution of viral RNA genomes are well documented, but few studies have characterized the rate and nature of ongoing genetic change over time under controlled experimental conditions, especially in plant hosts. The RNA genome of satellite tobacco mosaic virus (STMV) was used as an effective model for such studies because of advantageous features of its genome structure and because the extant genetic heterogeneity of STMV has been characterized previously. In the present study, the process of genetic change over time was studied by monitoring multiple serial passage lines of STMV populations for changes in their consensus sequences. A total of 42 passage lines were initiated by inoculation of tobacco plants with a helper tobamovirus and one of four STMV RNA inocula that were transcribed from full-length infectious STMV clones or extracted from purified STMV type strain virions. Ten serial passages were carried out for each line and the consensus genotypes of progeny STMV populations were assessed for genetic change by RNase protection analyses of the entire 1,059-nt STMV genome. Three different types of genetic change were observed, including the fixation of novel mutations in 9 of 42 lines, mutation at the major heterogeneity site near nt 751 in 5 of the 19 lines inoculated with a single genotype, and selection of a single major genotype in 6 of the 23 lines inoculated with mixed genotypes. Sequence analyses showed that the majority of mutations were single base substitutions. The distribution of mutation sites included three clusters in which mutations occurred at or very near the same site, suggesting hot spots of genetic change in the STMV genome. The diversity of genetic changes in sibling lines is clear evidence for the important role of chance and random sampling events in the process of genetic diversification of STMV virus populations.

  13. Radiation and biophysical studies on cells and viruses. Progress report, 1 April 1975--31 March 1976

    International Nuclear Information System (INIS)

    Cole, A.; Ansevin, A.T.; Corry, P.M.; Humphrey, R.M.

    1976-01-01

    Progress is reported on the following research projects: studies on organization of chromosomes using sedimentation analysis, electron microscopy, and radiosensitive site analysis; studies on organization of nucleoproteins and DNA using thermal denaturation experiments; distribution of radiosensitive sites in mitotic and intraphase CHO cells using track and alpha particle irradiation; gamma ray and particle irradiation studies of cellular and nucleoprotein damage; and studies of semiconductor properties of biomolecules and applications to melanin-containing cells

  14. 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...

  15. Two and three dimensional characterization of Zucchini Yellow Mosaic Virus induced structural alterations in Cucurbita pepo L. plants.

    Science.gov (United States)

    Zellnig, Günther; Pöckl, Michael Herbert; Möstl, Stefan; Zechmann, Bernd

    2014-05-01

    Infection of plants by Zucchini Yellow Mosaic Virus (ZYMV) induces severe ultrastructural changes. The aim of this study was to investigate ultrastructural changes during ZYMV-infection in Cucurbita pepo L. plants on the two and three dimensional (2D and 3D) level and to correlate these changes with the spread of ZYMV throughout the plant by transmission electron microscopy (TEM) and image analysis. This study revealed that after inoculation of the cotyledons ZYMV moved into roots [3 days post inoculation (dpi)], then moved upwards into the stem and apical meristem (5 dpi), then into the first true leaf (7 dpi) and could finally be found in all plant parts (9 dpi). ZYMV-infected cells contained viral inclusion bodies in the form of cylindrical inclusions (CIs). These CIs occurred in four different forms throughout the cytosol of roots and leaves: scrolls and pinwheels when cut transversely and long tubular structures and bundles of filaments when cut longitudinally. 3D reconstruction of ZYMV-infected cells containing scrolls revealed that they form long tubes throughout the cytosol. The majority has a preferred orientation and an average length and width of 3 μm and 120 nm, respectively. Image analysis revealed an increased size of cells and vacuoles (107% and 447%, respectively) in younger ZYMV-infected leaves leading to a similar ratio of cytoplasm to vacuole (about 1:1) in older and younger ZYMV-infected leaves which indicates advanced cell growth in younger tissues. The collected data advances the current knowledge about ZYMV-induced ultrastructural changes in Cucurbita pepo. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

  16. Application of FTA technology for sampling, recovery and molecular characterization of viral pathogens and virus-derived transgenes from plant tissues

    Science.gov (United States)

    Ndunguru, Joseph; Taylor, Nigel J; Yadav, Jitender; Aly, Haytham; Legg, James P; Aveling, Terry; Thompson, Graham; Fauquet, Claude M

    2005-01-01

    Background Plant viral diseases present major constraints to crop production. Effective sampling of the viruses infecting plants is required to facilitate their molecular study and is essential for the development of crop protection and improvement programs. Retaining integrity of viral pathogens within sampled plant tissues is often a limiting factor in this process, most especially when sample sizes are large and when operating in developing counties and regions remote from laboratory facilities. FTA is a paper-based system designed to fix and store nucleic acids directly from fresh tissues pressed into the treated paper. We report here the use of FTA as an effective technology for sampling and retrieval of DNA and RNA viruses from plant tissues and their subsequent molecular analysis. Results DNA and RNA viruses were successfully recovered from leaf tissues of maize, cassava, tomato and tobacco pressed into FTA® Classic Cards. Viral nucleic acids eluted from FTA cards were found to be suitable for diagnostic molecular analysis by PCR-based techniques and restriction analysis, and for cloning and nucleotide sequencing in a manner equivalent to that offered by tradition isolation methods. Efficacy of the technology was demonstrated both from sampled greenhouse-grown plants and from leaf presses taken from crop plants growing in farmer's fields in East Africa. In addition, FTA technology was shown to be suitable for recovery of viral-derived transgene sequences integrated into the plant genome. Conclusion Results demonstrate that FTA is a practical, economical and sensitive method for sampling, storage and retrieval of viral pathogens and plant genomic sequences, when working under controlled conditions and in the field. Application of this technology has the potential to significantly increase ability to bring modern analytical techniques to bear on the viral pathogens infecting crop plants. PMID:15904535

  17. Application of FTA technology for sampling, recovery and molecular characterization of viral pathogens and virus-derived transgenes from plant tissues.

    Science.gov (United States)

    Ndunguru, Joseph; Taylor, Nigel J; Yadav, Jitender; Aly, Haytham; Legg, James P; Aveling, Terry; Thompson, Graham; Fauquet, Claude M

    2005-05-18

    Plant viral diseases present major constraints to crop production. Effective sampling of the viruses infecting plants is required to facilitate their molecular study and is essential for the development of crop protection and improvement programs. Retaining integrity of viral pathogens within sampled plant tissues is often a limiting factor in this process, most especially when sample sizes are large and when operating in developing counties and regions remote from laboratory facilities. FTA is a paper-based system designed to fix and store nucleic acids directly from fresh tissues pressed into the treated paper. We report here the use of FTA as an effective technology for sampling and retrieval of DNA and RNA viruses from plant tissues and their subsequent molecular analysis. DNA and RNA viruses were successfully recovered from leaf tissues of maize, cassava, tomato and tobacco pressed into FTA Classic Cards. Viral nucleic acids eluted from FTA cards were found to be suitable for diagnostic molecular analysis by PCR-based techniques and restriction analysis, and for cloning and nucleotide sequencing in a manner equivalent to that offered by tradition isolation methods. Efficacy of the technology was demonstrated both from sampled greenhouse-grown plants and from leaf presses taken from crop plants growing in farmer's fields in East Africa. In addition, FTA technology was shown to be suitable for recovery of viral-derived transgene sequences integrated into the plant genome. Results demonstrate that FTA is a practical, economical and sensitive method for sampling, storage and retrieval of viral pathogens and plant genomic sequences, when working under controlled conditions and in the field. Application of this technology has the potential to significantly increase ability to bring modern analytical techniques to bear on the viral pathogens infecting crop plants.

  18. Detection of potato mop-top virus in soils and potato tubers using bait-plant bioassay, ELISA and RT-PCR.

    Science.gov (United States)

    Arif, Muhammad; Ali, Murad; Rehman, Anayatur; Fahim, Muhammad

    2014-01-01

    The hilly region of Northwest of Pakistan is leading seed potato producing areas of the country. Soil and plant samples were collected from the region and tested for PMTV using both conventional and molecular techniques. The bait plants exhibited PMTV-characteristic v-shaped yellow leaf markings in Nicotiana debneyi plants grown in putative viruliferious soils from 20/26 locations. The results were confirmed by back inoculation of sap from both roots and leaves of bait plant on indicator hosts (N. debneyi, Nicotiana benthamiana). The root samples of bait plants grown in soils of 25 locations and leaves of 24 locations reproduced systemic infection on indicator hosts upon back inoculation. The virus was identified in bait plants grown in soils from 25/26 locations using double antibody sandwich-enzyme linked immunosorbent assay (DAS)-ELISA and reverse transcription and polymerase chain reaction (RT-PCR) methods. The products of the 566bp were amplified from coat protein region of PMTV RNA 3 in both root and leaf samples of baited plants. The virus was detected in 10 potato cultivars commercially grown in the region using DAS-ELISA and RT-PCR. The virus was also detected in zoospores of Spongospora subterranea derived from the peels of selected scabby tubers using triple antibody sandwich (TAS)-ELISA. The results indicate that a bait plant bioassay, infectivity assay, ELISA and RT-PCR can detect PMTV in roots and leaves of baited plants, field samples, zoospores of S. subterranea and tubers of 10 potato cultivars commercially grown in the region. Copyright © 2013 Elsevier B.V. All rights reserved.

  19. Application of FTA technology for sampling, recovery and molecular characterization of viral pathogens and virus-derived transgenes from plant tissues

    Directory of Open Access Journals (Sweden)

    Aveling Terry

    2005-05-01

    Full Text Available Abstract Background Plant viral diseases present major constraints to crop production. Effective sampling of the viruses infecting plants is required to facilitate their molecular study and is essential for the development of crop protection and improvement programs. Retaining integrity of viral pathogens within sampled plant tissues is often a limiting factor in this process, most especially when sample sizes are large and when operating in developing counties and regions remote from laboratory facilities. FTA is a paper-based system designed to fix and store nucleic acids directly from fresh tissues pressed into the treated paper. We report here the use of FTA as an effective technology for sampling and retrieval of DNA and RNA viruses from plant tissues and their subsequent molecular analysis. Results DNA and RNA viruses were successfully recovered from leaf tissues of maize, cassava, tomato and tobacco pressed into FTA® Classic Cards. Viral nucleic acids eluted from FTA cards were found to be suitable for diagnostic molecular analysis by PCR-based techniques and restriction analysis, and for cloning and nucleotide sequencing in a manner equivalent to that offered by tradition isolation methods. Efficacy of the technology was demonstrated both from sampled greenhouse-grown plants and from leaf presses taken from crop plants growing in farmer's fields in East Africa. In addition, FTA technology was shown to be suitable for recovery of viral-derived transgene sequences integrated into the plant genome. Conclusion Results demonstrate that FTA is a practical, economical and sensitive method for sampling, storage and retrieval of viral pathogens and plant genomic sequences, when working under controlled conditions and in the field. Application of this technology has the potential to significantly increase ability to bring modern analytical techniques to bear on the viral pathogens infecting crop plants.

  20. Transformation of tobacco plant (Nicotiana tabacum L. with the recombinant hepatitis B virus genes 35SHBsAg and 35SHBsAgER

    Directory of Open Access Journals (Sweden)

    Juliana Martins Ribeiro

    2010-03-01

    Full Text Available The recombinant surface antigen of hepatitis B virus (HBsAg, purified from transgenic plants, proved to be efficient when utilized for raising anti-HB antibodies for the prevention of hepatitis B. Because of the important role of the HBsAg antigen in hepatitis B prevention, the coding sequence of HBsAg antigen, with or without the addition of the carboxi-terminus sequence for protein retention in the endoplasmatic reticulum, was linked to cauliflower mosaic virus 35S promoter, tobacco mosaic virus leader sequence Ω, and the transcription terminator sequence. The aim of this work was to clone the chimeric gene 35SHBsAgER in the plant expression vector pGPTV/Kan/Asc. The resulting plasmid, called pG35SHBsAgER, and another plasmid produced previously in our laboratory called pG35SHBsAg, were transferred to Agrobacterium tumefaciens, and tobacco leaves, of the SR1 cultivar were used as explants for genetic transformation. Twenty-one fully regenerated plants were obtained (10 for the pG35SHBsAg construction and 11 for the pG35SHBsAgER construction. The genomic DNA of all plants was analyzed by PCR, and the presence of the transgene was confirmed in all plants.

  1. Stock indexing and Potato virus Y elimination from potato plants cultivated in vitro Indexação de matrizes e eliminação do Potato virus Y em plantas de batata cultivadas in vitro

    Directory of Open Access Journals (Sweden)

    Luciana Cordeiro Nascimento

    2003-01-01

    Full Text Available Potato cultivars (Solanum tuberosum L. have shown degeneration or run out caused by viruses after several cycles of propagation using seed tubers from commercial fields. This work reports the occurrence of single and mixed infections of four potato viruses in Paraíba-Brazil and presents a method for Potato virus Y (PVY elimination, by using thermo-and chemotherapies. Plants of potato cv. Baraka were tested by direct antigen coating ELISA. Antisera against PVY, Potato virus X (PVX, Potato virus S (PVS, and Potato leafroll virus (PLRV were used. Materials with positive reaction to PVY were treated for virus elimination. Single node cuttings (1.0 cm length were excised and inoculated in Murashige & Skoog (MS medium, supplemented with 1.0 mg L-1 of kinetin, 0.001 mg L-1 of naphthalene acetic acid (NAA and 0.1 mg L-1 of gibberellic acid (GA3. The thermotherapy at approximately 37ºC, during 30 and 40 days, resulted in 20.0 and 37.5% PVY elimination, respectively. Chemotherapy was undertaken with Ribavirin (RBV, 5-Azacytidine (AZA, and 3-Deazauridine (DZD. The RBV showed the highest rate of virus eradication, with 55.5% virus-free plants. Simultaneous thermo and chemotherapy had higher efficiency for the elimination of PVY, reaching rates of healthy plants of 83.3% with RBV, 70.0% with AZA, and 50.0% with DZD.Cultivares de batata (Solanum tuberosum L. têm mostrado degenerescência causada por vírus após ciclos sucessivos do uso de tubérculos de campos comerciais como material propagativo. Este trabalho verifica a ocorrência de infecção simples e mista de quatro vírus da batata na Paraíba e apresenta adequação da técnica de cultivo in vitro para obtenção de material livre de Potato virus Y (PVY, incluindo uso de microestacas, termo e quimioterapia. Plantas de batata do cv. Baraka foram submetidas à indexação sorológica pelo teste "direct antigen coating" ELISA. Utilizaram-se antissoros contra o PVY, Potato virus X (PVX, Potato virus

  2. Radiation and biophysical studies on cells and viruses. Progress report, April 1, 1976--June 30, 1977. [Gamma radiation, alpha particles

    Energy Technology Data Exchange (ETDEWEB)

    Cole, A.

    1977-01-01

    Progress is reported on the following research projects: genetic structure of DNA, chromosomes, and nucleoproteins; particle beam studies of radiosensitive sites; division delay in CHO cells induced by partly penetrating alpha particles; location of cellular sites for mutation induction; sites for radioinduced cell transformation using partly penetrating particle beams; gamma-ray and particle irradiation of nucleoproteins and other model systems; quantitation of surface antigens on normal and neoplastic cells by x-ray fluorescence; hyperthermic effects on cell survival and DNA repair mechanisms; and studies on radioinduced cell transformation. (HLW)

  3. Effect of curtovirus species competitiveness in host plants on transmission and incidence of Beet severe curly top virus and Beet mild curly top virus

    Science.gov (United States)

    Curly top disease, caused by viruses in the genus Curtovirus, causes significant economic losses for sugarbeet and other crops throughout the western United States. Recent studies demonstrated the two most abundant curtovirus species in the US are Beet severe curly top virus (BSCTV) and Beet mild c...

  4. Effect of urdbean leaf crinkle virus infection on total soluble protein and antioxidant enzymes in blackgram plants

    International Nuclear Information System (INIS)

    Ashfaq, M.; Mughal, S.M.; Khan, A.; Javed, N.; Sahi, S.T.; Shahid, M.

    2010-01-01

    Urdbean leaf crinkle virus (ULCV) is a common, wide spread, destructive and economically important disease causing systemic infection in blackgram (Vigna mungo (L.) Hepper), resulting in extreme crinkling, curling, puckering and rugosity of leaves, and yield reductions. Effect of viral infection was investigated on total soluble proteins and antioxidant enzymes activity in two genotypes viz., Mash-88-susceptible and CM-2002-resistant, at different growth stages under both the inoculated and un-inoculated conditions. ULCV infection resulted in significant increase in total soluble protein contents of the leaves in both genotypes. In healthy plant, super oxide dismutase (SOD), catalase (CAT) and peroxidase (PO) showed similar activity levels. In inoculated plants of Mash-88, SOD and PO activities decreased and increased non-significantly at all growth stages, respectively. The activities of PO and SOD increased and decreased significantly after 15 and 30 days of inoculation in resistant genotype, respectively. No significant changes in catalase (CAT) activity were detected in ULCV-infected leaves over the control. It was concluded that the super oxide dismutase and peroxidases might be associated with resistance/susceptibility to ULCV infection. (author)

  5. Tomato yellow leaf curl virus infection mitigates the heat stress response of plants grown at high temperatures

    Science.gov (United States)

    Ghandi, Anfoka; Adi, Moshe; Lilia, Fridman; Linoy, Amrani; Or, Rotem; Mikhail, Kolot; Mouhammad, Zeidan; Henryk, Czosnek; Rena, Gorovits

    2016-01-01

    Cultured tomatoes are often exposed to a combination of extreme heat and infection with Tomato yellow leaf curl virus (TYLCV). This stress combination leads to intense disease symptoms and yield losses. The response of TYLCV-susceptible and resistant tomatoes to heat stress together with viral infection was compared. The plant heat-stress response was undermined in TYLCV infected plants. The decline correlated with the down-regulation of heat shock transcription factors (HSFs) HSFA2 and HSFB1, and consequently, of HSF-regulated genes Hsp17, Apx1, Apx2 and Hsp90. We proposed that the weakened heat stress response was due to the decreased capacity of HSFA2 to translocate into the nuclei of infected cells. All the six TYLCV proteins were able to interact with tomato HSFA2 in vitro, moreover, coat protein developed complexes with HSFA2 in nuclei. Capturing of HSFA2 by viral proteins could suppress the transcriptional activation of heat stress response genes. Application of both heat and TYLCV stresses was accompanied by the development of intracellular large protein aggregates containing TYLCV proteins and DNA. The maintenance of cellular chaperones in the aggregated state, even after recovery from heat stress, prevents the circulation of free soluble chaperones, causing an additional decrease in stress response efficiency. PMID:26792235

  6. 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.

  7. Human T-cell leukemia virus type 1 Tax and cell cycle progression: role of cyclin D-cdk and p110Rb.

    Science.gov (United States)

    Neuveut, C; Low, K G; Maldarelli, F; Schmitt, I; Majone, F; Grassmann, R; Jeang, K T

    1998-06-01

    Human T-cell leukemia virus type 1 is etiologically linked to the development of adult T-cell leukemia and various human neuropathies. The Tax protein of human T-cell leukemia virus type I has been implicated in cellular transformation. Like other oncoproteins, such as Myc, Jun, and Fos, Tax is a transcriptional activator. How it mechanistically dysregulates the cell cycle is unclear. Previously, it was suggested that Tax affects cell-phase transition by forming a direct protein-protein complex with p16(INK4a), thereby inactivating an inhibitor of G1-to-S-phase progression. Here we show that, in T cells deleted for p16(INK4a), Tax can compel an egress of cells from G0/G1 into S despite the absence of serum. We also show that in undifferentiated myocytes, expression of Tax represses cellular differentiation. In both settings, Tax expression was found to increase cyclin D-cdk activity and to enhance pRb phosphorylation. In T cells, a Tax-associated increase in steady-state E2F2 protein was also documented. In searching for a molecular explanation for these observations, we found that Tax forms a protein-protein complex with cyclin D3, whereas a point-mutated and transcriptionally inert Tax mutant failed to form such a complex. Interestingly, expression of wild-type Tax protein in cells was also correlated with the induction of a novel hyperphosphorylated cyclin D3 protein. Taken together, these findings suggest that Tax might directly influence cyclin D-cdk activity and function, perhaps by a route independent of cdk inhibitors such as p16(INK4a).

  8. 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.

  9. Infection rates and comparative population dynamics of Peregrinus maidis (Hemiptera: Delphacidae) on corn plants with and without symptoms of maize mosaic virus (Rhabdoviridae: Nucleorhabdovirus) infection.

    Science.gov (United States)

    Higashi, C H V; Bressan, A

    2013-10-01

    We examined the population dynamics of the corn planthopper Peregrinus maidis (Ashmead) (Hemiptera: Delphacidae) throughout a cycle of corn (Zea mays L.) production on plants with or without symptoms of maize mosaic virus (MMV) (Rhabdoviridae: Nucleorhabdovirus) infection. Our results indicate that the timing of MMV plant infection greatly influenced the planthopper's host plant colonization patterns. Corn plants that expressed symptoms of MMV infection early in the crop cycle (28 d after planting) harbored, on average, 40 and 48% fewer planthoppers than plants that expressed symptoms of MMV infection later in the crop cycle (49 d after planting) and asymptomatic plants, respectively. We also observed a change in the number of brachypterous (short-wing type) and macropterous (long-wing type) winged forms produced; plants expressing early symptoms of MMV infection harbored, on average, 41 and 47% more of the brachypterous form than plants with late infections of MMV and plants with no symptoms of MMV, respectively. Furthermore, we determined the rates of MMV-infected planthoppers relative to their wing morphology (macropterous or brachypterous) and gender. MMV infection was 5 and 12% higher in females than in males in field and greenhouse experiments, respectively; however, these differences were not significantly different. This research provides evidence that MMV similarly infects P. maidis planthoppers regardless of the gender and wing morphotype. These results also suggest that the timing of symptom development greatly affects the population dynamics of the planthopper vector, and likely has important consequences for the dynamics of the disease in the field.

  10. Interference in plant defense and development by non-structural protein NSs of Groundnut bud necrosis virus.

    Science.gov (United States)

    Goswami, Suneha; Sahana, Nandita; Pandey, Vanita; Doblas, Paula; Jain, R K; Palukaitis, Peter; Canto, Tomas; Praveen, Shelly

    2012-01-01

    Groundnut bud necrosis virus (GBNV) infects a large number of leguminous and solanaceous plants. To elucidate the biological function of the non-structural protein encoded by the S RNA of GBNV (NSs), we studied its role in RNA silencing suppression and in viral pathogenesis. Our results demonstrated that GBNV NSs functions as a suppressor of RNA silencing using the agroinfiltration patch assay. An in silico analysis suggested the presence of pro-apoptotic protein Reaper-like sequences in the GBNV NSs, which were known to be present in animal infecting bunyaviruses. Utilizing NSs mutants, we demonstrated that a Leu-rich domain was required for RNA silencing suppression activity, but not the non-overlapping Trp/GH3 motif of the Reaper-like sequence. To investigate the role of NSs in symptom development we generated transgenic tomato expressing the GBNV NSs and showed that the expression of NSs in tomato mimics symptoms induced by infection with GBNV, such as leaf senescence and necrosis. As leaf senescence is controlled by miR319 regulation of the transcription factor TCP1, we assessed the accumulation of both RNAs in transgenic NSs-expressing and GBNV-infected tomato plants. In both types of plants the levels of miR319 decreased, while the levels of TCP1 transcripts increased. We propose that GBNV-NSs affects miRNA biogenesis through its RNA silencing suppressor activity and interferes with TCP1-regulated leaf developmental pathways. Copyright © 2011 Elsevier B.V. All rights reserved.

  11. Using small RNA (sRNA) deep sequencing to understand global virus distribution in plants

    Science.gov (United States)

    Small RNAs (sRNAs), a class of regulatory RNAs, have been used to serve as the specificity determinants of suppressing gene expression in plants and animals. Next generation sequencing (NGS) uncovered the sRNA landscape in most organisms including their associated microbes. In the current study, w...

  12. Evaluation of virus removal efficiency of coagulation-sedimentation and rapid sand filtration processes in a drinking water treatment plant in Bangkok, Thailand.

    Science.gov (United States)

    Asami, Tatsuya; Katayama, Hiroyuki; Torrey, Jason Robert; Visvanathan, Chettiyappan; Furumai, Hiroaki

    2016-09-15

    In order to properly assess and manage the risk of infection by enteric viruses in tap water, virus removal efficiency should be evaluated quantitatively for individual processes in actual drinking water treatment plants (DWTPs); however, there have been only a few studies due to technical difficulties in quantifying low virus concentration in water samples. In this study, the removal efficiency of indigenous viruses was evaluated for coagulation-sedimentation (CS) and rapid sand filtration (RSF) processes in a DWTP in Bangkok, Thailand by measuring the concentration of viruses before and after treatment processes using real-time polymerase chain reaction (qPCR). Water samples were collected and concentrated from raw source water, after CS, and after RSF, and inhibitory substances in water samples were reduced by use of a hydrophobic resin (DAX-8). Pepper mild mottle virus (PMMoV) and JC polyomavirus (JC PyV) were found to be highly prevalent in raw waters, with concentrations of 10(2.88 ± 0.35) and 10(3.06 ± 0.42) copies/L (geometric mean ± S.D.), respectively. Step-wise removal efficiencies were calculated for individual processes, with some variation observed between wet and dry seasons. During the wet season, PMMoV was removed less by CS and more by RSF on average (0.40 log10 vs 1.26 log10, respectively), while the reverse was true for JC PyV (1.91 log10 vs 0.49 log10, respectively). Both viruses were removed similarly during the dry season, with CS removing the most virus (PMMoV, 1.61 log10 and 0.78 log10; JC PyV, 1.70 log10, and 0.59 log10; CS and RSF, respectively). These differences between seasons were potentially due to variations in raw water quality and the characteristics of the viruses themselves. These results suggest that PMMoV and JC PyV, which are more prevalent in environmental waters than the other enteric viruses evaluated in this study, could be useful in determining viral fate for the risk management of viruses in water treatment

  13. The synergistic effect of chemical carcinogens enhances Epstein-Barr virus reactivation and tumor progression of nasopharyngeal carcinoma cells.

    Science.gov (United States)

    Fang, Chih-Yeu; Huang, Sheng-Yen; Wu, Chung-Chun; Hsu, Hui-Yu; Chou, Sheng-Ping; Tsai, Ching-Hwa; Chang, Yao; Takada, Kenzo; Chen, Jen-Yang

    2012-01-01

    Seroepidemiological studies imply a correlation between Epstein-Barr virus (EBV) reactivation and the development of nasopharyngeal carcinoma (NPC). N-nitroso compounds, phorbols, and butyrates are chemicals found in food and herb samples collected from NPC high-risk areas. These chemicals have been reported to be risk factors contributing to the development of NPC, however, the underlying mechanism is not fully understood. We have demonstrated previously that low dose N-methyl-N'-nitro-N-nitrosoguanidine (MNNG, 0.1 µg/ml) had a synergistic effect with 12-O-tetradecanoylphorbol-13-acetate (TPA) and sodium butyrate (SB) in enhancing EBV reactivation and genome instability in NPC cells harboring EBV. Considering that residents in NPC high-risk areas may contact regularly with these chemical carcinogens, it is vital to elucidate the relation between chemicals and EBV and their contributions to the carcinogenesis of NPC. In this study, we constructed a cell culture model to show that genome instability, alterations of cancer hallmark gene expression, and tumorigenicity were increased after recurrent EBV reactivation in NPC cells following combined treatment of TPA/SB and MNNG. NPC cells latently infected with EBV, NA, and the corresponding EBV-negative cell, NPC-TW01, were periodically treated with MNNG, TPA/SB, or TPA/SB combined with MNNG. With chemically-induced recurrent reactivation of EBV, the degree of genome instability was significantly enhanced in NA cells treated with a combination of TPA/SB and MNNG than those treated individually. The Matrigel invasiveness, as well as the tumorigenicity in mouse, was also enhanced in NA cells after recurrent EBV reactivation. Expression profile analysis by microarray indicates that many carcinogenesis-related genes were altered after recurrent EBV reactivation, and several aberrations observed in cell lines correspond to alterations in NPC lesions. These results indicate that cooperation between chemical carcinogens can

  14. Recovery of Nicotiana benthamiana plants from a necrotic response induced by a nepovirus is associated with RNA silencing but not with reduced virus titer.

    Science.gov (United States)

    Jovel, Juan; Walker, Melanie; Sanfaçon, Hélène

    2007-11-01

    Recovery of plants from virus-induced symptoms is often described as a consequence of RNA silencing, an antiviral defense mechanism. For example, recovery of Nicotiana clevelandii from a nepovirus (tomato black ring virus) is associated with a decreased viral RNA concentration and sequence-specific resistance to further virus infection. In this study, we have characterized the interaction of another nepovirus, tomato ringspot virus (ToRSV), with host defense responses during symptom induction and subsequent recovery. Early in infection, ToRSV induced a necrotic phenotype in Nicotiana benthamiana that showed characteristics typical of a hypersensitive response. RNA silencing was also activated during ToRSV infection, as evidenced by the presence of ToRSV-derived small interfering RNAs (siRNAs) that could direct degradation of ToRSV sequences introduced into sensor constructs. Surprisingly, disappearance of symptoms was not accompanied by a commensurate reduction in viral RNA levels. The stability of ToRSV RNA after recovery was also observed in N. clevelandii and Cucumis sativus and in N. benthamiana plants carrying a functional RNA-dependent RNA polymerase 1 ortholog from Medicago truncatula. In experiments with a reporter transgene (green fluorescent protein), ToRSV did not suppress the initiation or maintenance of transgene silencing, although the movement of the silencing signal was partially hindered. Our results demonstrate that although RNA silencing is active during recovery, reduction of virus titer is not required for the initiation of this phenotype. This scenario adds an unforeseen layer of complexity to the interaction of nepoviruses with the host RNA silencing machinery. The possibility that viral proteins, viral RNAs, and/or virus-derived siRNAs inactivate host defense responses is discussed.

  15. Extraction of total nucleic acid based on silica-coated magnetic particles for RT-qPCR detection of plant RNA virus/viroid.

    Science.gov (United States)

    Sun, Ning; Deng, Congliang; Zhao, Xiaoli; Zhou, Qi; Ge, Guanglu; Liu, Yi; Yan, Wenlong; Xia, Qiang

    2014-02-01

    In this study, a nucleic acid extraction method based on silica-coated magnetic particles (SMPs) and RT-qPCR assay was developed to detect Arabis mosaic virus (ArMV), Lily symptomless virus (LSV), Hop stunt viroid (HSVd) and grape yellow speckle viroid 1 (GYSVd-1). The amplification sequences of RT-qPCR were reversely transcribed in vitro as RNA standard templates. The standard curves covered six or seven orders of magnitude with a detection limit of 100 copies per each assay. Extraction efficiency of the SMPs method was evaluated by recovering spiked ssRNAs from plant samples and compared to two commercial kits (TRIzol and RNeasy Plant mini kit). Results showed that the recovery rate of SMPs method was comparable to the commercial kits when spiked ssRNAs were extracted from lily leaves, whereas it was two or three times higher than commercial kits when spiked ssRNAs were extracted from grapevine leaves. SMPs method was also used to extract viral nucleic acid from15 ArMV-positive lily leaf samples and 15 LSV-positive lily leaf samples. SMPs method did not show statistically significant difference from other methods on detecting ArMV, but LSV. The SMPs method has the same level of virus load as the TRIzol, and its mean virus load of was 0.5log10 lower than the RNeasy Plant mini kit. Nucleic acid was extracted from 19 grapevine-leaf samples with SMPs and the two commercial kits and subsequently screened for HSVd and GYSVd-1 by RT-qPCR. Regardless of HSVd or GYSVd-1, SMPs method outperforms other methods on both positive rate and the viroid load. In conclusion, SMPs method was able to efficiently extract the nucleic acid of RNA viruses or viroids, especially grapevine viroids, from lily-leaf or grapevine-leaf samples for RT-qPCR detection. Copyright © 2013 Elsevier B.V. All rights reserved.

  16. Avian leukosis virus subgroup J promotes cell proliferation and cell cycle progression through miR-221 by targeting CDKN1B.

    Science.gov (United States)

    Ren, Chaoqi; Yu, Mengmeng; Zhang, Yao; Fan, Minghui; Chang, Fangfang; Xing, Lixiao; Liu, Yongzhen; Wang, Yongqiang; Qi, Xiaole; Liu, Changjun; Zhang, Yanping; Cui, Hongyu; Li, Kai; Gao, Li; Pan, Qing; Wang, Xiaomei; Gao, Yulong

    2018-04-23

    Avian leukosis virus subgroup J (ALV-J), a highly oncogenic retrovirus, causes leukemia-like proliferative diseases in chickens. microRNAs post-transcriptionally suppress targets and are involved in the development of various tumors. We previously showed that miR-221 is upregulated in ALV-J-induced tumors. In this study, we analyzed the possible function of miR-221 in ALV-J tumorigenesis. The target validation system showed that CDKN1B is a target of miR-221 and is downregulated in ALV-J infection. As CDKN1B arrests the cell cycle and regulates its progression, we analyzed the proliferation of ALV-J-infected DF-1 cells. ALV-J-infection-induced DF1 cell derepression of G1/S transition and overproliferation required high miR-221 expression followed by CDKN1B downregulation. Cell cycle pathway analysis showed that ALV-J infection induced DF-1 cell overproliferation via the CDKN1B-CDK2/CDK6 pathway. Thus, miR-221 may play an important role in ALV-J-induced aggressive growth of DF-1 cells; these findings have expanded our insights into the mechanism underlying ALV-J infection and tumorigenesis. Copyright © 2018 Elsevier Inc. All rights reserved.

  17. Genetic variation in the interleukin-28B gene is associated with spontaneous clearance and progression of hepatitis C virus in Moroccan patients.

    Directory of Open Access Journals (Sweden)

    Sayeh Ezzikouri

    Full Text Available Genetic variation in the IL28B gene has been strongly associated with treatment outcomes, spontaneous clearance and progression of the hepatitis C virus infection (HCV. The aim of the present study was to investigate the role of polymorphisms at this locus with progression and outcome of HCV infection in a Moroccan population.We analyzed a cohort of 438 individuals among them 232 patients with persistent HCV infection, of whom 115 patients had mild chronic hepatitis and 117 had advanced liver disease (cirrhosis and hepatocellular carcinoma, 68 individuals who had naturally cleared HCV and 138 healthy subjects. The IL28B SNPs rs12979860 and rs8099917 were genotyped using a TaqMan 5' allelic discrimination assay.The protective rs12979860-C and rs8099917-T alleles were more common in subjects with spontaneous clearance (77.9% vs 55.2%; p = 0.00001 and 95.6% vs 83.2%; p = 0.0025, respectively. Individuals with clearance were 4.69 (95% CI, 1.99-11.07 times more likely to have the C/C genotype for rs12979860 polymorphism (p = 0.0017 and 3.55 (95% CI, 0.19-66.89 times more likely to have the T/T genotype at rs8099917. Patients with advanced liver disease carried the rs12979860-T/T genotype more frequently than patients with mild chronic hepatitis C (OR = 1.89; 95% CI, 0.99-3.61; p = 0.0532 and this risk was even more pronounced when we compared them with healthy controls (OR = 4.27; 95% CI, 2.08-8.76; p = 0.0005. The rs8099917-G allele was also associated with advanced liver disease (OR = 2.34; 95% CI, 1.40-3.93; p = 0.0100.In the Moroccan population, polymorphisms near the IL28B gene play a role both in spontaneous clearance and progression of HCV infection.

  18. Correction: Graillot, B.; et al. Progressive Adaptation of a CpGV Isolate to Codling Moth Populations Resistant to CpGV-M. Viruses 2014, 6, 5135–5144

    Directory of Open Access Journals (Sweden)

    Benoît Graillot

    2015-12-01

    Full Text Available In our article “Progressive Adaptation of a CpGV Isolate to Codling Moth Populations Resistant to CpGV-M.” (Viruses 2014, 6, 5135–5144; doi:10.3390/v6125135 [1] we obtained resistance values of the codling moth, Cydia pomonella, RGV laboratory colony [2], when challenged with Cydia pomonella Granulovirus, Mexican Isolate (CpGV-M, that were lower than those previously published [2]. Careful analysis of both the RGV colony and the CpGV-M virus stock used led to the realization that a low level contamination of this virus stock with CpGV-R5 occurred. We have made new tests with a verified stock, and the results are now in agreement with those previously published.

  19. Eukaryotic translation initiation factor 2B-beta (eIF2Bβ), a new class of plant virus resistance gene.

    Science.gov (United States)

    Shopan, Jannat; Mou, Haipeng; Zhang, Lili; Zhang, Changtong; Ma, Weiwei; Walsh, John A; Hu, Zhongyuan; Yang, Jinghua; Zhang, Mingfang

    2017-06-01

    Recessive resistances to plant viruses in the Potyvirus genus have been found to be based on mutations in the plant eukaryotic translation initiation factors, eIF4E and eIF4G or their isoforms. Here we report that natural, monogenic recessive resistance to the Potyvirus Turnip mosaic virus (TuMV) has been found in a number of mustard (Brassica juncea) accessions. Bulked segregant analysis and sequencing of resistant and susceptible plant lines indicated the resistance is controlled by a single recessive gene, recessive TuMV resistance 03 (retr03), an allele of the eukaryotic translation initiation factor 2B-beta (eIF2Bβ). Silencing of eIF2Bβ in a TuMV-susceptible mustard plant line and expression of eIF2Bβ from a TuMV-susceptible line in a TuMV-resistant mustard plant line confirmed the new resistance mechanism. A functional copy of a specific allele of eIF2Bβ is required for efficient TuMV infection. eIF2Bβ represents a new class of virus resistance gene conferring resistance to any pathogen. eIF2B acts as a guanine nucleotide exchange factor (GEF) for its GTP-binding protein partner eIF2 via interaction with eIF2·GTP at an early step in translation initiation. Further genotyping indicated that a single non-synonymous substitution (A120G) in the N-terminal region of eIF2Bβ was responsible for the TuMV resistance. A reproducible marker has been developed, facilitating marker-assisted selection for TuMV resistance in B. juncea. Our findings provide a new target for seeking natural resistance to potyviruses and new opportunities for the control of potyviruses using genome editing techniques targeted on eIF2Bβ. © 2017 The Authors The Plant Journal © 2017 John Wiley & Sons Ltd.

  20. Cryobiotechnology of apple (Malus spp.): development, progress and future prospects.

    Science.gov (United States)

    Wang, Min-Rui; Chen, Long; Teixeira da Silva, Jaime A; Volk, Gayle M; Wang, Qiao-Chun

    2018-05-01

    Cryopreservation provides valuable genes for further breeding of elite cultivars, and cryotherapy improves the production of virus-free plants in Malus spp., thus assisting the sustainable development of the apple industry. Apple (Malus spp.) is one of the most economically important temperate fruit crops. Wild Malus genetic resources and existing cultivars provide valuable genes for breeding new elite cultivars and rootstocks through traditional and biotechnological breeding programs. These valuable genes include those resistant to abiotic factors such as drought and salinity, and to biotic factors such as fungi, bacteria and aphids. Over the last three decades, great progress has been made in apple cryobiology, making Malus one of the most extensively studied plant genera with respect to cryopreservation. Explants such as pollen, seeds, in vivo dormant buds, and in vitro shoot tips have all been successfully cryopreserved, and large Malus cryobanks have been established. Cryotherapy has been used for virus eradication, to obtain virus-free apple plants. Cryopreservation provided valuable genes for further breeding of elite cultivars, and cryotherapy improved the production of virus-free plants in Malus spp., thus assisting the sustainable development of the apple industry. This review provides updated and comprehensive information on the development and progress of apple cryopreservation and cryotherapy. Future research will reveal new applications and uses for apple cryopreservation and cryotherapy.

  1. The progressive adaptation of a georgian isolate of African swine fever virus to vero cells leads to a gradual attenuation of virulence in swine corresponding to major modifications of the viral genome.

    Science.gov (United States)

    Krug, Peter W; Holinka, Lauren G; O'Donnell, Vivian; Reese, Bo; Sanford, Brenton; Fernandez-Sainz, Ignacio; Gladue, Douglas P; Arzt, Jonathan; Rodriguez, Luis; Risatti, Guillermo R; Borca, Manuel V

    2015-02-01

    African swine fever virus (ASFV) causes a contagious and often lethal disease of feral and domestic swine. Experimental vaccines derived from naturally occurring, genetically modified, or cell culture-adapted ASFV have been evaluated, but no commercial vaccine is available to control African swine fever (ASF). We report here the genotypic and phenotypic analysis of viruses obtained at different passages during the process of adaptation of a virulent ASFV field isolate from the Republic of Georgia (ASFV-G) to grow in cultured cell lines. ASFV-G was successively passaged 110 times in Vero cells. Viruses obtained at passages 30, 60, 80, and 110 were evaluated in vitro for the ability to replicate in Vero cells and primary swine macrophages cultures and in vivo for assessing virulence in swine. Replication of ASFV-G in Vero cells increased with successive passages, corresponding to a decreased replication in primary swine macrophages cultures. In vivo, progressive loss of virus virulence was observed with increased passages in Vero cells, and complete attenuation of ASFV-G was observed at passage 110. Infection of swine with the fully attenuated virus did not confer protection against challenge with virulent parental ASFV-G. Full-length sequence analysis of each of these viruses revealed significant deletions that gradually accumulated in specific areas at the right and left variable ends of the genome. Mutations that result in amino acid substitutions and frameshift mutations were also observed, though in a rather limited number of genes. The potential importance of these genetic changes in virus adaptation/attenuation is discussed. The main problem in controlling ASF is the lack of vaccines. Attempts to produce vaccines by adaptation of ASFV to cultured cell lines have been made. These attempts led to the production of attenuated viruses that conferred only homologous protection. Specifics regarding adaptation of these isolates to cell cultures have been

  2. Resistance or tolerance to the golden mosaic virus of bean plant (Phaseolus vulgaris L.), obtained by mutation induction

    International Nuclear Information System (INIS)

    Tulmann Neto, A.

    1979-09-01

    Experiments were carried out with the objective of selecting, evaluation and using induced mutants of Phaseolus vulgaris L. resistant or tolerant to golden mosaic - a virus disease of beans. Seeds from three bean cultivars were treated with gamma-ray or the chemical mutagen ethyl methanesulphonate (EMS). After golden mosaic inoculation of 50,000 M 2 seedlings, in a insectary, screening was made and a tolerant mutant (TMD-1) was selected. Evaluation of TMD-1 was carried out by comparing it with the parent cultivar Carioca, indicating that, although showing lower productivity than the original material, (what prevented it from being used directly on a commercial basis), it maintained the same reaction to rust, bacterial blight, and common mosaic. Studies on the genetic basis of the mutation were also done. The possibility of using this mutant in a plant breeding programme aimed at obtaining resistance to golden mosaic was demonstrated in crosses between TMD-1 and two cultivars, to which transference of tolerance was possible. (Author) [pt

  3. Functional expression of an ajmaline pathway-specific esterase from Rauvolfia in a novel plant-virus expression system.

    Science.gov (United States)

    Ruppert, Martin; Woll, Jörn; Giritch, Anatoli; Genady, Ezzat; Ma, Xueyan; Stöckigt, Joachim

    2005-11-01

    Acetylajmalan esterase (AAE) plays an essential role in the late stage of ajmaline biosynthesis. Based on the partial peptide sequences of AAE isolated and purified from Rauvolfia cell suspensions, a full-length AAE cDNA clone was isolated. The amino acid sequence of AAE has the highest level of identity of 40% to putative lipases known from the Arabidopsis thaliana genome project. Based on the primary structure AAE is a new member of the GDSL lipase superfamily. The expression in Escherichia coli failed although a wide range of conditions were tested. With a novel virus-based plant expression system, it was possible to express AAE functionally in leaves of Nicotiana benthamiana Domin. An extraordinarily high enzyme activity was detected in the Nicotiana tissue, which exceeded that in Rauvolfia serpentina (L.) Benth. ex Kurz cell suspension cultures about 20-fold. This expression allowed molecular analysis of AAE for the first time and increased the number of functionally expressed alkaloid genes from Rauvolfia now to eight, and the number of ajmaline pathway-specific cDNAs to a total of six.

  4. Complete genome sequence and integrated protein localization and interaction map for alfalfa dwarf virus, which combines properties of both cytoplasmic and nuclear plant rhabdoviruses

    Energy Technology Data Exchange (ETDEWEB)

    Bejerman, Nicolás, E-mail: n.bejerman@uq.edu.au [Instituto de Patología Vegetal (IPAVE), Centro de Investigaciones Agropecuarias (CIAP), Instituto Nacional de Tecnología Agropecuaria INTA, Camino a 60 Cuadras k 5,5, Córdoba X5020ICA (Argentina); Queensland Alliance for Agriculture and Food Innovation, The University of Queensland, St Lucia, QLD 4072 (Australia); Giolitti, Fabián; Breuil, Soledad de; Trucco, Verónica; Nome, Claudia; Lenardon, Sergio [Instituto de Patología Vegetal (IPAVE), Centro de Investigaciones Agropecuarias (CIAP), Instituto Nacional de Tecnología Agropecuaria INTA, Camino a 60 Cuadras k 5,5, Córdoba X5020ICA (Argentina); Dietzgen, Ralf G. [Queensland Alliance for Agriculture and Food Innovation, The University of Queensland, St Lucia, QLD 4072 (Australia)

    2015-09-15

    Summary: We have determined the full-length 14,491-nucleotide genome sequence of a new plant rhabdovirus, alfalfa dwarf virus (ADV). Seven open reading frames (ORFs) were identified in the antigenomic orientation of the negative-sense, single-stranded viral RNA, in the order 3′-N-P-P3-M-G-P6-L-5′. The ORFs are separated by conserved intergenic regions and the genome coding region is flanked by complementary 3′ leader and 5′ trailer sequences. Phylogenetic analysis of the nucleoprotein amino acid sequence indicated that this alfalfa-infecting rhabdovirus is related to viruses in the genus Cytorhabdovirus. When transiently expressed as GFP fusions in Nicotiana benthamiana leaves, most ADV proteins accumulated in the cell periphery, but unexpectedly P protein was localized exclusively in the nucleus. ADV P protein was shown to have a homotypic, and heterotypic nuclear interactions with N, P3 and M proteins by bimolecular fluorescence complementation. ADV appears unique in that it combines properties of both cytoplasmic and nuclear plant rhabdoviruses. - Highlights: • The complete genome of alfalfa dwarf virus is obtained. • An integrated localization and interaction map for ADV is determined. • ADV has a genome sequence similarity and evolutionary links with cytorhabdoviruses. • ADV protein localization and interaction data show an association with the nucleus. • ADV combines properties of both cytoplasmic and nuclear plant rhabdoviruses.

  5. Complete genome sequence and integrated protein localization and interaction map for alfalfa dwarf virus, which combines properties of both cytoplasmic and nuclear plant rhabdoviruses

    International Nuclear Information System (INIS)

    Bejerman, Nicolás; Giolitti, Fabián; Breuil, Soledad de; Trucco, Verónica; Nome, Claudia; Lenardon, Sergio; Dietzgen, Ralf G.

    2015-01-01

    Summary: We have determined the full-length 14,491-nucleotide genome sequence of a new plant rhabdovirus, alfalfa dwarf virus (ADV). Seven open reading frames (ORFs) were identified in the antigenomic orientation of the negative-sense, single-stranded viral RNA, in the order 3′-N-P-P3-M-G-P6-L-5′. The ORFs are separated by conserved intergenic regions and the genome coding region is flanked by complementary 3′ leader and 5′ trailer sequences. Phylogenetic analysis of the nucleoprotein amino acid sequence indicated that this alfalfa-infecting rhabdovirus is related to viruses in the genus Cytorhabdovirus. When transiently expressed as GFP fusions in Nicotiana benthamiana leaves, most ADV proteins accumulated in the cell periphery, but unexpectedly P protein was localized exclusively in the nucleus. ADV P protein was shown to have a homotypic, and heterotypic nuclear interactions with N, P3 and M proteins by bimolecular fluorescence complementation. ADV appears unique in that it combines properties of both cytoplasmic and nuclear plant rhabdoviruses. - Highlights: • The complete genome of alfalfa dwarf virus is obtained. • An integrated localization and interaction map for ADV is determined. • ADV has a genome sequence similarity and evolutionary links with cytorhabdoviruses. • ADV protein localization and interaction data show an association with the nucleus. • ADV combines properties of both cytoplasmic and nuclear plant rhabdoviruses

  6. 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

  7. Advances in virus research. Volume 29

    International Nuclear Information System (INIS)

    Lauffer, M.A.; Maramorosch, K.

    1984-01-01

    This book contains nine chapters. Some of the titles are: Molecular Biology of Wound Tumor Virus; The Application of Monoclonal Antibodies in the Study of Viruses; Prions: Novel Infectious Pathogens; and Monoclonal Antibodies Against Plant Viruses

  8. Incidence of infection in 39-month-old ewes with TMEM154 diplotypes "1 1," "1 3," and "3 3" after natural exposure to ovine progressive pneumonia virus.

    Science.gov (United States)

    Leymaster, K A; Chitko-McKown, C G; Heaton, M P

    2015-01-01

    Production and well-being of sheep and goats in many countries are harmfully impacted by small ruminant lentiviruses (SRLV) that cause incurable, progressive diseases. Susceptibility to ovine progressive pneumonia virus (OPPV), the North American form of SRLV, is influenced by variants of the ovine transmembrane protein 154 gene (TMEM154). The experimental objective was to estimate additive and dominance effects of TMEM154 haplotypes 1 and 3 on susceptibility of breeding ewes to infection after natural exposure to OPPV from birth to 39 mo of age. Sires and dams were heterozygous for TMEM154 haplotypes 1 and 3, producing ewe lambs with diplotypes "1 1," "1 3," and "3 3." These lambs were raised by mature, infected dams to ensure natural, maternal exposure to OPPV. Ewe lambs (n = 108) were kept for breeding and joined an infected flock of ewes to guarantee natural, nonmaternal exposure to OPPV. Ewes were bred to lamb at 1, 2, and 3 yr of age. Serum samples were collected at breeding, 1 mo before lambing and shortly after weaning each year to monitor infection status to 39 mo of age. During the experiment, 9 of the 108 ewes died while uninfected and data collected on these ewes were not analyzed. Infection status of the remaining 99 ewes at 39 mo of age was analyzed using logistic regression procedures. Effects of ewe type of birth, ewe type of rearing, and breed type of dam were not detected (P > 0.10), and the estimated sire variance component was nil. Ewe diplotype affected infection status (P ewes with diplotypes "1 1," "1 3," and "3 3" were 0.10, 0.88, and 0.89, respectively, and confidence intervals for diplotypes "1 3" and "3 3" were distinct from "1 1." Haplotype 3 was completely dominant to haplotype 1 at 39 mo of age. The probability of infection for ewes with either diplotype "1 3" or "3 3" averaged 8.5 times that of ewes with diplotype "1 1." Diplotype "1 3" and "3 3" ewes were highly susceptible to nonmaternal transmission of OPPV, in contrast to

  9. Evaluation of the effect of short-term treatment with the integrase inhibitor raltegravir (Isentress) on the course of progressive feline leukemia virus infection.

    Science.gov (United States)

    Boesch, Andrea; Cattori, Valentino; Riond, Barbara; Willi, Barbara; Meli, Marina L; Rentsch, Katharina M; Hosie, Margaret J; Hofmann-Lehmann, Regina; Lutz, Hans

    2015-02-25

    Cats persistently infected with the gammaretrovirus feline leukemia virus (FeLV) are at risk to die within months to years from FeLV-associated disease, such as immunosuppression, anemia or lymphoma/leukemia. The integrase inhibitor raltegravir has been demonstrated to reduce FeLV replication in vitro. The aim of the present study was to investigate raltegravir in vivo for its safety and efficacy to suppress FeLV replication. The safety was tested in three naïve specified pathogen-free (SPF) cats during a 15 weeks treatment period (initially 20mg then 40mg orally b.i.d.). No adverse effects were noted. The efficacy was tested in seven persistently FeLV-infected SPF cats attained from 18 cats experimentally exposed to FeLV-A/Glasgow-1. The seven cats were treated during nine weeks (40mg then 80mg b.i.d.). Raltegravir was well tolerated even at the higher dose. A significant decrease in plasma viral RNA loads (∼5×) was found; however, after treatment termination a rebound effect was observed. Only one cat developed anti-FeLV antibodies and viral RNA loads remained decreased after treatment termination. Of note, one of the untreated FeLV-A infected cats developed fatal FeLV-C associated anemia within 5 weeks of FeLV-A infection. Moreover, progressive FeLV infection was associated with significantly lower enFeLV loads prior to infection supporting that FeLV susceptibility may be related to the genetic background of the cat. Overall, our data demonstrate the ability of raltegravir to reduce viral replication also in vivo. However, no complete control of viremia was achieved. Further investigations are needed to find an optimized treatment against FeLV. (250 words). Copyright © 2014 Elsevier B.V. All rights reserved.

  10. Progressão da circulação do vírus do dengue no Estado da Bahia, 1994-2000 Progression of dengue virus circulation in the State of Bahia, Brazil, 1994-2000

    Directory of Open Access Journals (Sweden)

    Maria Suely Silva Melo

    2010-04-01

    Full Text Available INTRODUÇÃO: A força da reemergência do vírus do dengue e a gravidade destas infecções colocaram esta doença na agenda de prioridades das instituições responsáveis pela proteção à saúde das populações. Aspecto importante para a compreensão da epidemiologia do dengue nos dias atuais refere-se ao conhecimento dos padrões da difusão espaço-temporal, entretanto são escassas as investigações que abordam esta questão. Este estudo descreve o processo de difusão do dengue no estado da Bahia, de 1994 a 2000. MÉTODOS: Trata-se de estudo ecológico espaço-temporal, tendo como unidades de análise município, semana epidemiológica, mês, trimestre e ano. Procedeu-se construção da curva de tendência e realizou-se mapeamento seqüencial da ocorrência de dengue por município para o período. RESULTADOS: Foram notificados 164.050 casos de dengue e a introdução desse vírus na Bahia, diferentemente de outros estados, se deu por um município de pequeno porte, constatando-se intermitência temporal e espacial nos registros de casos no início desta epidemia. Contudo, a partir de 1995 o processo de difusão da doença se deu de forma rápida e intensa. O vírus circulou em todas as zonas climáticas do estado o que revela o seu elevado poder de transmissão. A maior intensidade de detecção de casos e expansão territorial foi nas regiões úmidas e semi-úmidas do litoral, ideais para a sobrevivência e proliferação do vetor, e também, por serem mais densamente povoadas. CONCLUSÕES: Hipoteticamente, o padrão espaço-temporal intermitente de detecção de casos observado inicialmente, poderia permitir o controle da progressão da epidemia, caso houvesse ações de combate vetorial estruturadas.INTRODUCTION: The strength of the re-emergence of dengue virus and the severity of these infections put this disease in the priority agenda of the institutions responsible for protecting the health of populations. Important for

  11. Interdependence of plant water status with photosynthetic performance and root defense responses in Vigna radiata (L.) Wilczek under progressive drought stress and recovery.

    Science.gov (United States)

    Sengupta, Debashree; Guha, Anirban; Reddy, Attipalli Ramachandra

    2013-10-05

    The present study investigates the interdependence of plant water status with foliar and root responses in Vigna radiata L.Wilczek under progressive drought. Vegetatively-mature V. radiata plants were subjected to water withdrawal for 3 and 6days (D3 and D6, respectively) and then re-watered subsequently for 6days (6R) for stress-recovery. Changes in plant water status were expressed in terms of leaf and root moisture contents (LMC and RMC, respectively) and leaf relative water content (LRWC). Progressive drought caused apparent decrease in LRWC, LMC and RMC depicting significant level of dehydration of leaf and root tissues. Stomatal limitation alone could not account for the observed decrease in net CO2 assimilation rates (Pn) due to comparatively less decrease in sub-stomatal CO2 (Ci) concentrations with respect to other gas exchange parameters indicating possible involvement of non-stomatal limitations. Analysis of polyphasic chl a fluorescence kinetics during progressive drought showed decreased energy connectivity among PSII units as defined by a positive L-band with highest amplitude during D6. Efficiency of electron flux from OEC towards PSII acceptor side was not significantly affected during drought conditions as evidenced by the absence of a positive K-band. Increasing root-level water-limitation enforced a gradual oxidative stress through H2O2 accumulation and membrane lipid peroxidation in V. radiata roots exhibiting drastic enhancement of proline content and a significant but gradual increase in ascorbic acid content as well as guaiacol peroxidase activity under progressive drought. Expression analysis of Δ(1) pyrroline-5-carboxylate synthetase (P5CS) through real time PCR and enzyme activity studies showed a strong positive correlation between VrP5CS gene expression, enzyme activity and proline accumulation in the roots of V. radiata under progressive drought and recovery. Drought-induced changes in root moisture content (RMC) showed positive linear

  12. Sympton development, X-body formation and 126-kDa-protein in plants infected with tobacco mosaic virus

    NARCIS (Netherlands)

    Wijdeveld, M.M.G.

    1990-01-01

    Upon infection with tobacco mosaic virus (TMV) sensitive tobacco varieties develop systemic mosaic symptoms in the developing leaves. These symptoms are the visible result of the interaction of the virus with its host and the nature and the severity of the symptoms are determined

  13. The Impact of Human Papilloma Viruses, Matrix Metallo-Proteinases and HIV Protease Inhibitors on the Onset and Progression of Uterine Cervix Epithelial Tumors: A Review of Preclinical and Clinical Studies

    Directory of Open Access Journals (Sweden)

    Giovanni Barillari

    2018-05-01

    Full Text Available Infection of uterine cervix epithelial cells by the Human Papilloma Viruses (HPV is associated with the development of dysplastic/hyperplastic lesions, termed cervical intraepithelial neoplasia (CIN. CIN lesions may regress, persist or progress to invasive cervical carcinoma (CC, a leading cause of death worldwide. CIN is particularly frequent and aggressive in women infected by both HPV and the Human Immunodeficiency Virus (HIV, as compared to the general female population. In these individuals, however, therapeutic regimens employing HIV protease inhibitors (HIV-PI have reduced CIN incidence and/or clinical progression, shedding light on the mechanism(s of its development. This article reviews published work concerning: (i the role of HPV proteins (including HPV-E5, E6 and E7 and of matrix-metalloproteinases (MMPs in CIN evolution into invasive CC; and (ii the effect of HIV-PI on events leading to CIN progression such as basement membrane and extracellular matrix invasion by HPV-positive CIN cells and the formation of new blood vessels. Results from the reviewed literature indicate that CIN clinical progression can be monitored by evaluating the expression of MMPs and HPV proteins and they suggest the use of HIV-PI or their derivatives for the block of CIN evolution into CC in both HIV-infected and uninfected women.

  14. Type I J-domain NbMIP1 proteins are required for both Tobacco mosaic virus infection and plant innate immunity.

    Directory of Open Access Journals (Sweden)

    Yumei Du

    Full Text Available Tm-2² is a coiled coil-nucleotide binding-leucine rich repeat resistance protein that confers durable extreme resistance against Tomato mosaic virus (ToMV and Tobacco mosaic virus (TMV by recognizing the viral movement protein (MP. Here we report that the Nicotiana benthamiana J-domain MIP1 proteins (NbMIP1s associate with tobamovirus MP, Tm-2² and SGT1. Silencing of NbMIP1s reduced TMV movement and compromised Tm-2²-mediated resistance against TMV and ToMV. Furthermore, silencing of NbMIP1s reduced the steady-state protein levels of ToMV MP and Tm-2². Moreover, NbMIP1s are required for plant resistance induced by other R genes and the nonhost pathogen Pseudomonas syringae pv. tomato (Pst DC3000. In addition, we found that SGT1 associates with Tm-2² and is required for Tm-2²-mediated resistance against TMV. These results suggest that NbMIP1s function as co-chaperones during virus infection and plant immunity.

  15. Progress of nuclear safety for symbiosis and sustainability advanced digital instrumentation, control and information systems for nuclear power plants

    CERN Document Server

    Yoshikawa, Hidekazu

    2014-01-01

    This book introduces advanced methods of computational and information systems allowing readers to better understand the state-of-the-art design and implementation technology needed to maintain and enhance the safe operation of nuclear power plants. The subjects dealt with in the book are (i) Full digital instrumentation and control systems and human?machine interface technologies (ii) Risk? monitoring methods for large and? complex? plants (iii) Condition monitors for plant components (iv) Virtual and augmented reality for nuclear power plants and (v) Software reliability verification and val

  16. Industrial Fuel Gas Demonstration Plant Program. Monthly, quarterly and annual progress report, December 1978 and Calender Year 1978

    Energy Technology Data Exchange (ETDEWEB)

    None

    1978-01-01

    A new pilot plant program developed by DOE and the team members, was started on September 20, 1978. Pilot plant success was achieved in obtaining an ash balanced condition for several days with ash agglomeration with a pure coal feed. This was the objective of the first three months of the approved program.

  17. Virus-mediated chemical changes in rice plants impact the relationship between non-vector planthopper Nilaparvata lugens Stål and its egg parasitoid Anagrus nilaparvatae Pang et Wang.

    Science.gov (United States)

    He, Xiaochan; Xu, Hongxing; Gao, Guanchun; Zhou, Xiaojun; Zheng, Xusong; Sun, Yujian; Yang, Yajun; Tian, Junce; Lu, Zhongxian

    2014-01-01

    In order to clarify the impacts of southern rice black-streaked dwarf virus (SRBSDV) infection on rice plants, rice planthoppers and natural enemies, differences in nutrients and volatile secondary metabolites between infected and healthy rice plants were examined. Furthermore, the impacts of virus-mediated changes in plants on the population growth of non-vector brown planthopper (BPH), Nilaparvata lugens, and the selectivity and parasitic capability of planthopper egg parasitoid Anagrus nilaparvatae were studied. The results showed th