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Sample records for plasma rna viral

  1. Detection of Viral RNA in Tissues following Plasma Clearance from an Ebola Virus Infected Patient.

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    Mirella Biava

    2017-01-01

    Full Text Available An unprecedented Ebola virus (EBOV epidemic occurred in 2013-2016 in West Africa. Over this time the epidemic exponentially grew and moved to Europe and North America, with several imported cases and many Health Care Workers (HCW infected. Better understanding of EBOV infection patterns in different body compartments is mandatory to develop new countermeasures, as well as to fully comprehend the pathways of human-to-human transmission. We have longitudinally explored the persistence of EBOV-specific negative sense genomic RNA (neg-RNA and the presence of positive sense RNA (pos-RNA, including both replication intermediate (antigenomic-RNA and messenger RNA (mRNA molecules, in the upper and lower respiratory tract, as compared to plasma, in a HCW infected with EBOV in Sierra Leone, who was hospitalized in the high isolation facility of the National Institute for Infectious Diseases "Lazzaro Spallanzani" (INMI, Rome, Italy. We observed persistence of pos-RNA and neg-RNAs in longitudinally collected specimens of the lower respiratory tract, even after viral clearance from plasma, suggesting possible local replication. The purpose of the present study is to enhance the knowledge on the biological features of EBOV that can contribute to the human-to-human transmissibility and to develop effective intervention strategies. However, further investigation is needed in order to better understand the clinical meaning of viral replication and shedding in the respiratory tract.

  2. Viral protein Nef is detected in plasma of half of HIV-infected adults with undetectable plasma HIV RNA.

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    Jana Ferdin

    Full Text Available To address the role of translationally active HIV reservoir in chronic inflammation and non-AIDS related disorders, we first need a simple and accurate assay to evaluate viral protein expression in virally suppressed subjects.We optimized an HIV Nef enzyme-linked immunosorbent assay (ELISA and used it to quantify plasma Nef levels as an indicator of the leaky HIV reservoir in an HIV-infected cohort.This study accessed 134 plasma samples from a well-characterized cohort study of HIV-infected and uninfected adults in San Francisco (the SCOPE cohort. We optimized an ELISA for detection of plasma Nef in HIV-negative subjects and HIV-infected non-controllers, and evaluated its utility to quantify plasma Nef levels in a cross-sectional study of ART-suppressed and elite controller HIV-infected subjects.Here, we describe the performance of an optimized HIV Nef ELISA. When we applied this assay to the study cohort we found that plasma Nef levels were correlated with plasma HIV RNA levels in untreated disease. However, we were able to detect Nef in plasma of approximately half of subjects on ART or with elite control, despite the lack of detectable plasma HIV RNA levels using standard assays. Plasma Nef levels were not consistently associated with CD4+ T-cell count, CD8+ T-cell count, self-reported nadir CD4+ T-cell count or the CD4+/CD8+ T-cell ratio in HIV-infected subjects.Since plasma HIV RNA levels are undetectable in virally suppressed subjects, it is reasonable to assume that viral protein expression in leaky reservoir, and not plasma virions, is the source of Nef accumulating in plasma. To examine this further, improvements of the assay sensitivity, by lowering the background through improvements in the quality of Nef antibodies, and detailed characterization of the HIV reservoirs are needed.

  3. Association between feline immunodeficiency virus (FIV) plasma viral RNA load, concentration of acute phase proteins and disease severity.

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    Kann, Rebecca K C; Seddon, Jennifer M; Kyaw-Tanner, Myat T; Henning, Joerg; Meers, Joanne

    2014-08-01

    Veterinarians have few tools to predict the rate of disease progression in FIV-infected cats. In contrast, in HIV infection, plasma viral RNA load and acute phase protein concentrations are commonly used as predictors of disease progression. This study evaluated these predictors in cats naturally infected with FIV. In older cats (>5 years), log10 FIV RNA load was higher in the terminal stages of disease compared to the asymptomatic stage. There was a significant association between log10 FIV RNA load and both log10 serum amyloid A concentration and age in unwell FIV-infected cats. This study suggests that viral RNA load and serum amyloid A warrant further investigation as predictors of disease status and prognosis in FIV-infected cats. Copyright © 2014 Elsevier Ltd. All rights reserved.

  4. Nucleocapsid-Independent Specific Viral RNA Packaging via Viral Envelope Protein and Viral RNA Signal

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    Narayanan, Krishna; Chen, Chun-Jen; Maeda, Junko; Makino, Shinji

    2003-01-01

    For any of the enveloped RNA viruses studied to date, recognition of a specific RNA packaging signal by the virus's nucleocapsid (N) protein is the first step described in the process of viral RNA packaging. In the murine coronavirus a selective interaction between the viral transmembrane envelope protein M and the viral ribonucleoprotein complex, composed of N protein and viral RNA containing a short cis-acting RNA element, the packaging signal, determines the selective RNA packaging into vi...

  5. Full Viral Suppression, Low-Level Viremia, and Quantifiable Plasma HIV-RNA at the End of Pregnancy in HIV-Infected Women on Antiretroviral Treatment.

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    Baroncelli, Silvia; Pirillo, Maria F; Tamburrini, Enrica; Guaraldi, Giovanni; Pinnetti, Carmela; Degli Antoni, Anna; Galluzzo, Clementina M; Stentarelli, Chiara; Amici, Roberta; Floridia, Marco

    2015-07-01

    There is limited information on full viral suppression and low-level HIV-RNA viremia in HIV-infected women at the end of pregnancy. We investigated HIV-RNA levels close to delivery in women on antiretroviral treatment in order to define rates of complete suppression, low-level viremia, and quantifiable HIV-RNA, exploring as potential determinants some clinical and viroimmunological variables. Plasma samples from a national study in Italy, collected between 2003 and 2012, were used. According to plasma HIV-RNA levels, three groups were defined: full suppression (target not detected), low-level viremia (target detected but HIV-RNA (≥37 copies/ml). Multivariable logistic regression was used to define determinants of full viral suppression and of quantifiable HIV-RNA. Among 107 women evaluated at a median gestational age of 35 weeks, 90 (84.1%) had HIV-RNA HIV-RNA was 109 copies/ml (IQR 46-251), with only one case showing resistance (mutation M184V; rate: 9.1%). In multivariable analyses, women with higher baseline HIV-RNA levels and with hepatitis C virus (HCV) coinfection were significantly more likely to have quantifiable HIV-RNA in late pregnancy. Full viral suppression was significantly more likely with nonnucleoside reverse transcriptase inhibitor (NNRTI)-based regimens and significantly less likely with higher HIV-RNA in early pregnancy. No cases of HIV transmission occurred. In conclusion, HIV-infected pregnant women showed a high rate of viral suppression and a low resistance rate before delivery. In most cases no target HIV-RNA was detected in plasma, suggesting a low risk of subsequent virological rebound and development of resistance. Women with high levels of HIV-RNA in early pregnancy and those who have concomitant HCV infection should be considered at higher risk of having quantifiable HIV-RNA at the end of pregnancy.

  6. Full Viral Suppression, Low-Level Viremia, and Quantifiable Plasma HIV-RNA at the End of Pregnancy in HIV-Infected Women on Antiretroviral Treatment

    OpenAIRE

    Baroncelli, Silvia; Pirillo, Maria F.; Tamburrini, Enrica; Guaraldi, Giovanni; Pinnetti, Carmela; Antoni, Anna Degli; Galluzzo, Clementina M.; Stentarelli, Chiara; Amici, Roberta; Floridia, Marco

    2015-01-01

    There is limited information on full viral suppression and low-level HIV-RNA viremia in HIV-infected women at the end of pregnancy. We investigated HIV-RNA levels close to delivery in women on antiretroviral treatment in order to define rates of complete suppression, low-level viremia, and quantifiable HIV-RNA, exploring as potential determinants some clinical and viroimmunological variables. Plasma samples from a national study in Italy, collected between 2003 and 2012, were used. According ...

  7. Circular viral DNA detection and junction sequence analysis from PBMC of SHIV-infected cynomolgus monkeys with undetectable virus plasma RNA

    International Nuclear Information System (INIS)

    Cara, Andrea; Maggiorella, Maria Teresa; Bona, Roberta; Sernicola, Leonardo; Baroncelli, Silvia; Negri, Donatella R.M.; Leone, Pasqualina; Fagrouch, Zahra; Heeney, Jonathan; Titti, Fausto; Cafaro, Aurelio; Ensoli, Barbara

    2004-01-01

    Extrachromosomal forms of human immunodeficiency virus (HIV)-1 can be detected in peripheral blood mononuclear cell (PBMC) from HIV-infected patients in the absence of detectable viral replication and are thought to be a sign of active but cryptic virus replication. No information, however, are available on whether these forms are also present in animal models for acquired immunodeficiency syndrome (AIDS) and on their relation with other methods of detection of virus replication. To this aim, a polymerase chain reaction (PCR) approach was used to detect and analyze unintegrated circular 2-LTR-containing forms in PBMC of simian human immunodeficiency virus (SHIV)89.6P infected cynomolgus monkeys with RNA levels ranging between 1.8x10 6 and less than 50 copies/ml of plasma. 2-LTR forms were detected in 96.5% of monkeys' samples above 50 copies/ml of plasma, whereas they were present in 75.8% of monkeys' samples below 50 copies/ml of plasma. Persistence of unintegrated viral DNA in monkeys with undetectable plasma RNA could indicate either stability in non-dividing cells or ongoing low levels of viral replication in dividing cells

  8. ACVP-02: Plasma SIV/SHIV RNA Viral Load Measurements through the AIDS and Cancer Virus Program Quantitative Molecular Diagnostics Core | Frederick National Laboratory for Cancer Research

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    The SIV plasma viral load assay performed by the Quantitative Molecular Diagnostics Core (QMDC) utilizes reagents specifically designed to detect and accurately quantify the full range of SIV/SHIV viral variants and clones in common usage in the rese

  9. Plasma HIV-1 RNA viral load rebound among people who inject drugs receiving antiretroviral therapy (ART) in a Canadian setting: an ethno-epidemiological study.

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    Small, Will; Milloy, M J; McNeil, Ryan; Maher, Lisa; Kerr, Thomas

    2016-01-01

    People who inject drugs (PWID) living with HIV often experience sub-optimal antiretroviral therapy (ART) treatment outcomes, including HIV plasma viral load (PVL) rebound. While previous studies have identified risk factors for PVL rebound among PWID, no study has examined the perspectives of PWID who have experienced PVL rebound episodes. We conducted an ethno-epidemiological study to investigate the circumstances surrounding the emergence of rebound episodes among PWID in Vancouver, BC, Canada. Comprehensive clinical records linked to a community-based prospective observational cohort of HIV-positive drug users were used to identify PWID who had recently experienced viral rebound. In-depth qualitative interviews with 16 male and 11 female participants explored participant perspectives regarding the emergence of viral rebound. A timeline depicting each participant's HIV viral load and adherence to ART was used to elicit discussion of circumstances surrounding viral rebound. Viral rebound episodes were shaped by interplay between various individual, social, and environmental factors that disrupted routines facilitating adherence. Structural-environmental influences resulting in non-adherence included housing transitions, changes in drug use patterns and intense drug scene involvement, and inadequate care for co-morbid health conditions. Social-environmental influences on ART adherence included poor interactions between care providers and patients producing non-adherence, and understandings of HIV treatment that fostered intentional treatment discontinuation. This study describes key pathways which led to rebound episodes among PWID receiving ART and illustrates how environmental forces may increase vulnerability for non-adherence leading to treatment failure. Our findings have potential to help inform interventions and supports that address social-structural forces that foster non-adherence among PWID.

  10. Dengue viral RNA levels in peripheral blood mononuclear cells are associated with disease severity and preexisting dengue immune status.

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    Anon Srikiatkhachorn

    Full Text Available Infection with dengue viruses (DENV causes a wide range of manifestations from asymptomatic infection to a febrile illness called dengue fever (DF, to dengue hemorrhagic fever (DHF. The in vivo targets of DENV and the relation between the viral burden in these cells and disease severity are not known.The levels of positive and negative strand viral RNA in peripheral blood monocytes, T/NK cells, and B cells and in plasma of DF and DHF cases were measured by quantitative RT-PCR.Positive strand viral RNA was detected in monocytes, T/NK cells and B cells with the highest amounts found in B cells. Viral RNA levels in CD14+ cells and plasma were significantly higher in DHF compared to DF, and in cases with a secondary infection compared to those undergoing a primary infection. The distribution of viral RNA among cell subpopulations was similar in DF and DHF cases. Small amounts of negative strand RNA were found in a few cases only. The severity of plasma leakage correlated with viral RNA levels in plasma and in CD14+ cells.B cells were the principal cells containing DENV RNA in peripheral blood, but overall there was little active DENV RNA replication detectable in peripheral blood mononuclear cells (PBMC. Secondary infection and DHF were associated with higher viral burden in PBMC populations, especially CD14+ monocytes, suggesting that viral infection of these cells may be involved in disease pathogenesis.

  11. Viral RNA polymerase scanning and the gymnastics of Sendai virus RNA synthesis

    International Nuclear Information System (INIS)

    Kolakofsky, Daniel; Le Mercier, Philippe; Iseni, Frederic; Garcin, Dominique

    2004-01-01

    mRNA synthesis from nonsegmented negative-strand RNA virus (NNV) genomes is unique in that the genome RNA is embedded in an N protein assembly (the nucleocapsid) and the viral RNA polymerase does not dissociate from the template after release of each mRNA, but rather scans the genome RNA for the next gene-start site. A revised model for NNV RNA synthesis is presented, in which RNA polymerase scanning plays a prominent role. Polymerase scanning of the template is known to occur as the viral transcriptase negotiates gene junctions without falling off the template

  12. Longer duration of homelessness is associated with a lower likelihood of non-detectable plasma HIV-1 RNA viral load among people who use illicit drugs in a Canadian setting.

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    Loh, Jane; Kennedy, Mary Clare; Wood, Evan; Kerr, Thomas; Marshall, Brandon; Parashar, Surita; Montaner, Julio; Milloy, M-J

    2016-11-01

    Homelessness is common among people who use drugs (PWUD) and, for those living with HIV/AIDS, an important contributor to sub-optimal HIV treatment outcomes. This study aims to investigate the relationship between the duration of homelessness and the likelihood of plasma HIV-1 RNA viral load (VL) non-detectability among a cohort of HIV-positive PWUD. We used data from the ACCESS study, a long-running prospective cohort study of HIV-positive PWUD linked to comprehensive HIV clinical records including systematic plasma HIV-1 RNA VL monitoring. We estimated the longitudinal relationship between the duration of homelessness and the likelihood of exhibiting a non-detectable VL (i.e., effects modelling. Between May 1996 and June 2014, 922 highly active antiretroviral therapy-exposed participants were recruited and contributed 8188 observations. Of these, 4800 (59%) were characterized by non-detectable VL. Participants reported they were homeless in 910 (11%) interviews (median: six months, interquartile range: 6-12 months). A longer duration of homelessness was associated with lower odds of VL non-detectability (adjusted odds ratio = 0.71 per six-month period of homelessness, 95% confidence interval: 0.60-0.83) after adjustment for age, ancestry, drug use patterns, engagement in addiction treatment, and other potential confounders. Longer durations of episodes of homelessness in this cohort of HIV-positive illicit drug users were associated with a lower likelihood of plasma VL non-detectability. Our findings suggest that interventions that seek to promptly house homeless individuals, such as Housing First approaches, might assist in maximizing the clinical and public health benefits of antiretroviral therapy among people living with HIV/AIDS.

  13. siRNA as an alternative therapy against viral infections

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    Hana A. Pawestri

    2012-07-01

    Full Text Available siRNA (small interfering ribonucleic acid adalah sebuah metode yang dapat digunakan untuk mengatasi infeksi virus yang prinsip kerjanya berdasarkan metode komplementer dsRNA (double stranded RNA pada RNA virus sehingga menyebabkan kegagalan proses transkripsi (silencing.  Untuk lebih memahami bagaimana proses kerja dan ulasan penelitian siRNA yang terkini, di dalam tulisan ini ditinjau siRNA sebagai metoda yang dikembangkan untuk mengatasi infeksi dan meneliti efeknya pada replikasi beberapa virus seperti Hepatitis C, Influenza, Polio, dan HIV. Kami menemukan bahwa urutan basa nukleotida dari target siRNA sangat penting. Hal tersebut harus homolog dengan target RNA virus dan tidak menganggu RNA sel inang. Untuk mengurangi kegagalan terapi siRNA oleh adanya mutasi, digunakan beberapa siRNA yang sekaligus menjadi target RNA virus yang berbeda. Namun demikian, terapi siRNA masih menghadapi beberapa kesulitan seperti pengiriman (transfer khusus ke jaringan yang terinfeksi dan perlindungan siRNA dari perusakan oleh nuklease. Berdasarkan beberapa penelitian yang telah dilakukan, siRNA dapat digunakan sebagai alternatif untuk mengobati infeksi yang disebabkan oleh virus. Terapi tersebut direkomendasikan untuk dilakukan uji klinis dengan memperhatikan beberapa aspek seperti desain siRNA dan mekanisme transfer. (Health Science Indones 2010; 1: 58 - 65 Kata kunci: siRNA, infeksi virus, target virus, alternatif terapi Abstract SiRNA is a promising method to deal with viral infections. The principle of siRNA is based on the complementarily of (synthetic dsRNA to an RNA virus which, in consequence, will be silenced. Many studies are currently examining the effects of siRNA on replication of diverse virus types like Hepatitis C, polio and HIV. The choice of the siRNA target sequence is crucial. It has to be very homologous to the target RNA, but it cannot target RNA of the host cell. To reduce the possibility for the virus to escape from the siRNA therapy by

  14. Viral tRNA Mimicry from a Biocommunicative Perspective

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    Ascensión Ariza-Mateos

    2017-12-01

    Full Text Available RNA viruses have very small genomes which limits the functions they can encode. One of the strategies employed by these viruses is to mimic key factors of the host cell so they can take advantage of the interactions and activities these factors typically participate in. The viral RNA genome itself was first observed to mimic cellular tRNA over 40 years ago. Since then researchers have confirmed that distinct families of RNA viruses are accessible to a battery of cellular factors involved in tRNA-related activities. Recently, potential tRNA-like structures have been detected within the sequences of a 100 mRNAs taken from human cells, one of these being the host defense interferon-alpha mRNA; these are then additional to the examples found in bacterial and yeast mRNAs. The mimetic relationship between tRNA, cellular mRNA, and viral RNA is the central focus of two considerations described below. These are subsequently used as a preface for a final hypothesis drawing on concepts relating to mimicry from the social sciences and humanities, such as power relations and creativity. Firstly, the presence of tRNA-like structures in mRNAs indicates that the viral tRNA-like signal could be mimicking tRNA-like elements that are contextualized by the specific carrier mRNAs, rather than, or in addition to, the tRNA itself, which would significantly increase the number of potential semiotic relations mediated by the viral signals. Secondly, and in particular, mimicking a host defense mRNA could be considered a potential new viral strategy for survival. Finally, we propose that mRNA’s mimicry of tRNA could be indicative of an ancestral intracellular conflict in which species of mRNAs invaded the cell, but from within. As the meaning of the mimetic signal depends on the context, in this case, the conflict that arises when the viral signal enters the cell can change the meaning of the mRNAs’ internal tRNA-like signals, from their current significance to that

  15. Impact of collection method on assessment of semen HIV RNA viral load.

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    Brendan J W Osborne

    Full Text Available The blood HIV RNA viral load is the best-defined predictor of HIV transmission, in part due to ease of measurement and the correlation of blood and genital tract (semen or cervico-vaginal viral load, although recent studies found semen HIV RNA concentration to be a stronger predictor of HIV transmission. There is currently no standardized method for semen collection when measuring HIV RNA concentration. Therefore, we compared two collection techniques in order to study of the impact of antiretroviral therapy on the semen viral load.Semen was collected by masturbation from HIV-infected, therapy-naïve men who have sex with men (MSM either undiluted (Visit 1 or directly into transport medium (Visit 2. Seminal plasma was then isolated, and the HIV RNA concentration obtained with each collection technique was measured and corrected for dilution if necessary. Collection of semen directly into transport medium resulted in a median HIV RNA viral load that was 0.4 log10 higher than undiluted samples.The method of semen collection is an important consideration when quantifying the HIV RNA viral load in this compartment.

  16. Potyviral VPg enhances viral RNA Translation and inhibits reporter mRNA translation in planta.

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    Eskelin, Katri; Hafrén, Anders; Rantalainen, Kimmo I; Mäkinen, Kristiina

    2011-09-01

    Viral protein genome-linked (VPg) plays a central role in several stages of potyvirus infection. This study sought to answer questions about the role of Potato virus A (PVA; genus Potyvirus) VPg in viral and host RNA expression. When expressed in Nicotiana benthamiana leaves in trans, a dual role of VPg in translation is observed. It repressed the expression of monocistronic luciferase (luc) mRNA and simultaneously induced a significant upregulation in the expression of both replicating and nonreplicating PVA RNAs. This enhanced viral gene expression was due at least to the 5' untranslated region (UTR) of PVA RNA, eukaryotic initiation factors 4E and iso 4E [eIF4E/eIF(iso)4E], and the presence of a sufficient amount of VPg. Coexpression of VPg with viral RNA increased the viral RNA amount, which was not the case with the monocistronic mRNA. Both mutations at certain lysine residues in PVA VPg and eIF4E/eIF(iso)4E depletion reduced its ability to upregulate the viral RNA expression. These modifications were also involved in VPg-mediated downregulation of monocistronic luc expression. These results suggest that VPg can titrate eIF4Es from capped monocistronic RNAs. Because VPg-mediated enhancement of viral gene expression required eIF4Es, it is possible that VPg directs eIF4Es to promote viral RNA expression. From this study it is evident that VPg can serve as a specific regulator of PVA expression by boosting the viral RNA amounts as well as the accumulation of viral translation products. Such a mechanism could function to protect viral RNA from being degraded and to secure efficient production of coat protein (CP) for virion formation.

  17. Potyviral VPg Enhances Viral RNA Translation and Inhibits Reporter mRNA Translation In Planta▿

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    Eskelin, Katri; Hafrén, Anders; Rantalainen, Kimmo I.; Mäkinen, Kristiina

    2011-01-01

    Viral protein genome-linked (VPg) plays a central role in several stages of potyvirus infection. This study sought to answer questions about the role of Potato virus A (PVA; genus Potyvirus) VPg in viral and host RNA expression. When expressed in Nicotiana benthamiana leaves in trans, a dual role of VPg in translation is observed. It repressed the expression of monocistronic luciferase (luc) mRNA and simultaneously induced a significant upregulation in the expression of both replicating and nonreplicating PVA RNAs. This enhanced viral gene expression was due at least to the 5′ untranslated region (UTR) of PVA RNA, eukaryotic initiation factors 4E and iso 4E [eIF4E/eIF(iso)4E], and the presence of a sufficient amount of VPg. Coexpression of VPg with viral RNA increased the viral RNA amount, which was not the case with the monocistronic mRNA. Both mutations at certain lysine residues in PVA VPg and eIF4E/eIF(iso)4E depletion reduced its ability to upregulate the viral RNA expression. These modifications were also involved in VPg-mediated downregulation of monocistronic luc expression. These results suggest that VPg can titrate eIF4Es from capped monocistronic RNAs. Because VPg-mediated enhancement of viral gene expression required eIF4Es, it is possible that VPg directs eIF4Es to promote viral RNA expression. From this study it is evident that VPg can serve as a specific regulator of PVA expression by boosting the viral RNA amounts as well as the accumulation of viral translation products. Such a mechanism could function to protect viral RNA from being degraded and to secure efficient production of coat protein (CP) for virion formation. PMID:21697470

  18. A discontinuous RNA platform mediates RNA virus replication: building an integrated model for RNA-based regulation of viral processes.

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    Baodong Wu

    2009-03-01

    Full Text Available Plus-strand RNA viruses contain RNA elements within their genomes that mediate a variety of fundamental viral processes. The traditional view of these elements is that of local RNA structures. This perspective, however, is changing due to increasing discoveries of functional viral RNA elements that are formed by long-range RNA-RNA interactions, often spanning thousands of nucleotides. The plus-strand RNA genomes of tombusviruses exemplify this concept by possessing different long-range RNA-RNA interactions that regulate both viral translation and transcription. Here we report that a third fundamental tombusvirus process, viral genome replication, requires a long-range RNA-based interaction spanning approximately 3000 nts. In vivo and in vitro analyses suggest that the discontinuous RNA platform formed by the interaction facilitates efficient assembly of the viral RNA replicase. This finding has allowed us to build an integrated model for the role of global RNA structure in regulating the reproduction of a eukaryotic RNA virus, and the insights gained have extended our understanding of the multifunctional nature of viral RNA genomes.

  19. Translation of a nonpolyadenylated viral RNA is enhanced by binding of viral coat protein or polyadenylation of the RNA.

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    Neeleman, L; Olsthoorn, R C; Linthorst, H J; Bol, J F

    2001-12-04

    On entering a host cell, positive-strand RNA virus genomes have to serve as messenger for the translation of viral proteins. Efficient translation of cellular messengers requires interactions between initiation factors bound to the 5'-cap structure and the poly(A) binding protein bound to the 3'-poly(A) tail. Initiation of infection with the tripartite RNA genomes of alfalfa mosaic virus (AMV) and viruses from the genus Ilarvirus requires binding of a few molecules of coat protein (CP) to the 3' end of the nonpolyadenylated viral RNAs. Moreover, infection with the genomic RNAs can be initiated by addition of the subgenomic messenger for CP, RNA 4. We report here that extension of the AMV RNAs with a poly(A) tail of 40 to 80 A-residues permitted initiation of infection independently of CP or RNA 4 in the inoculum. Specifically, polyadenylation of RNA 1 relieved an apparent bottleneck in the translation of the viral RNAs. Translation of RNA 4 in plant protoplasts was autocatalytically stimulated by its encoded CP. Mutations that interfered with CP binding to the 3' end of viral RNAs reduced translation of RNA 4 to undetectable levels. Possibly, CP of AMV and ilarviruses stimulates translation of viral RNAs by acting as a functional analogue of poly(A) binding protein or other cellular proteins.

  20. Intracellular Detection of Viral Transcription and Replication Using RNA FISH

    Science.gov (United States)

    2016-05-26

    Chapter 14. Intracellular detection of viral transcription and replication using RNA FISH i. Summary/Abstract Many hemorrhagic fever viruses...only allow entirely new investigations into the replication of these viruses, but also how this method can be applied to any virus with a known...localization, TurboFISH, hemorrhagic fever virus replication 1. Introduction RNA FISH was developed as a method to visualize cellular RNA by binding a

  1. Role of RNase MRP in viral RNA degradation and RNA recombination.

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    Jaag, Hannah M; Lu, Qiasheng; Schmitt, Mark E; Nagy, Peter D

    2011-01-01

    RNA degradation, together with RNA synthesis, controls the steady-state level of viral RNAs in infected cells. The endoribonucleolytic cleavage of viral RNA is important not only for viral RNA degradation but for RNA recombination as well, due to the participation of some RNA degradation products in the RNA recombination process. To identify host endoribonucleases involved in degradation of Tomato bushy stunt virus (TBSV) in a Saccharomyces cerevisiae model host, we tested eight known endoribonucleases. Here we report that downregulation of SNM1, encoding a component of the RNase MRP, and a temperature-sensitive mutation in the NME1 gene, coding for the RNA component of RNase MRP, lead to reduced production of the endoribonucleolytically cleaved TBSV RNA in yeast. We also show that the highly purified yeast RNase MRP cleaves the TBSV RNA in vitro, resulting in TBSV RNA degradation products similar in size to those observed in yeast cells. Knocking down the NME1 homolog in Nicotiana benthamiana also led to decreased production of the cleaved TBSV RNA, suggesting that in plants, RNase MRP is involved in TBSV RNA degradation. Altogether, this work suggests a role for the host endoribonuclease RNase MRP in viral RNA degradation and recombination.

  2. Anti-viral RNA silencing: do we look like plants ?

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    Lecellier Charles-Henri

    2006-01-01

    Full Text Available Abstract The anti-viral function of RNA silencing was first discovered in plants as a natural manifestation of the artificial 'co-suppression', which refers to the extinction of endogenous gene induced by homologous transgene. Because silencing components are conserved among most, if not all, eukaryotes, the question rapidly arose as to determine whether this process fulfils anti-viral functions in animals, such as insects and mammals. It appears that, whereas the anti-viral process seems to be similarly conserved from plants to insects, even in worms, RNA silencing does influence the replication of mammalian viruses but in a particular mode: micro(miRNAs, endogenous small RNAs naturally implicated in translational control, rather than virus-derived small interfering (siRNAs like in other organisms, are involved. In fact, these recent studies even suggest that RNA silencing may be beneficial for viral replication. Accordingly, several large DNA mammalian viruses have been shown to encode their own miRNAs. Here, we summarize the seminal studies that have implicated RNA silencing in viral infection and compare the different eukaryotic responses.

  3. UGGT1 enhances enterovirus 71 pathogenicity by promoting viral RNA synthesis and viral replication.

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    Peng-Nien Huang

    2017-05-01

    Full Text Available Positive-strand RNA virus infections can induce the stress-related unfolded protein response (UPR in host cells. This study found that enterovirus A71 (EVA71 utilizes host UDP-glucose glycoprotein glucosyltransferase 1 (UGGT1, a key endoplasmic reticulum protein (ER involved in UPR, to enhance viral replication and virulence. EVA71 forms replication complexes (RCs on cellular membranes that contain a mix of host and viral proteins to facilitate viral replication, but the components and processes involved in the assembly and function of RCs are not fully understood. Using EVA71 as a model, this study found that host UGGT1 and viral 3D polymerase co-precipitate along with other factors on membranous replication complexes to enhance viral replication. Increased UGGT1 levels elevated viral growth rates, while viral pathogenicity was observed to be lower in heterozygous knockout mice (Uggt1 +/- mice. These findings provide important insight on the role of UPR and host UGGT1 in regulating RNA virus replication and pathogenicity.

  4. Respiratory viral RNA on toys in pediatric office waiting rooms.

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    Pappas, Diane E; Hendley, J Owen; Schwartz, Richard H

    2010-02-01

    Toys in pediatric office waiting rooms may be fomites for transmission of viruses. Eighteen samples were taken from office objects on 3 occasions. Samples were tested for presence of picornavirus (either rhinovirus or enterovirus) on all 3 sample days; in addition, January samples were tested for respiratory syncytial virus and March samples were tested for influenza A and B. In addition, 15 samples were obtained from the sick waiting room before and after cleaning. Polymerase chain reaction was used to detect picornavirus, respiratory syncytial virus, and influenza A or B virus. Finally, 20 samples were obtained from the fingers of a researcher after handling different toys in the sick waiting room, and samples were then obtained from all the same toys; all samples were tested for picornavirus by polymerase chain reaction. Viral RNA was detected on 11 of 52 (21%) of toys sampled. Ten of the positives were picornavirus; 1 was influenza B virus. Three (30%) of 10 toys from the new toy bag, 6 of 30 (20%) in the sick child waiting room, and 2 of 12 (17%) in the well child waiting room were positive. Six (40%) of 15 toys in the sick waiting room were positive for picornaviral RNA before cleaning; after cleaning, 4 (27%) of 15 were positive in spite of the fact that RNA was removed from 4 of 6 of the original positives. Three (15%) of 20 toys in the sick waiting room were positive for picornaviral RNA, but RNA was not transferred to the fingers of the investigator who handled these toys. About 20% of the objects in a pediatric office may be contaminated with respiratory viral RNA, most commonly picornavirus RNA. Cleaning with a disinfectant cloth was only modestly effective in removing the viral RNA from the surfaces of toys, but transfer of picornaviral RNA from toys to fingers was inefficient.

  5. Adsorption of viral particles from the blood plasma of patients with viral hepatitis on nanodiamonds.

    Science.gov (United States)

    Baron, A V; Osipov, N V; Yashchenko, S V; Kokotukha, Yu A; Baron, I J; Puzyr, A P; Olkhovskiy, I A; Bondar, V S

    2016-07-01

    Adsorption of viral particles from the blood plasma of patients with viral hepatitis B and C on modified nanodiamonds (MNDs) was shown in the in vitro experiments. PCR method showed the treatment of plasma with MNDs leads to a decrease in the viral load by 2-3 orders of magnitude or more in both cases studied. These results make it possible to predict the applicability of MNDs for the development of new technologies of hemodialysis and plasmapheresis for binding and removal of viral particles from the blood of infected patients.

  6. Viral evasion of intracellular DNA and RNA sensing

    Science.gov (United States)

    Chan, Ying Kai; Gack, Michaela U.

    2016-01-01

    The co-evolution of viruses with their hosts has led to the emergence of viral pathogens that are adept at evading or actively suppressing host immunity. Pattern recognition receptors (PRRs) are key components of antiviral immunity that detect conserved molecular features of viral pathogens and initiate signalling that results in the expression of antiviral genes. In this Review, we discuss the strategies that viruses use to escape immune surveillance by key intracellular sensors of viral RNA or DNA, with a focus on RIG-I-like receptors (RLRs), cyclic GMP–AMP synthase (cGAS) and interferon-γ (IFNγ)-inducible protein 16 (IFI16). Such viral strategies include the sequestration or modification of viral nucleic acids, interference with specific post-translational modifications of PRRs or their adaptor proteins, the degradation or cleavage of PRRs or their adaptors, and the sequestration or relocalization of PRRs. An understanding of viral immune-evasion mechanisms at the molecular level may guide the development of vaccines and antivirals. PMID:27174148

  7. A Viral RNA Structural Element Alters Host Recognition of Nonself RNA

    Energy Technology Data Exchange (ETDEWEB)

    Hyde, J. L.; Gardner, C. L.; Kimura, T.; White, J. P.; Liu, G.; Trobaugh, D. W.; Huang, C.; Tonelli, M.; Paessler, S.; Takeda, K.; Klimstra, W. B.; Amarasinghe, G. K.; Diamond, M. S.

    2014-01-30

    Although interferon (IFN) signaling induces genes that limit viral infection, many pathogenic viruses overcome this host response. As an example, 2'-O methylation of the 5' cap of viral RNA subverts mammalian antiviral responses by evading restriction of Ifit1, an IFN-stimulated gene that regulates protein synthesis. However, alphaviruses replicate efficiently in cells expressing Ifit1 even though their genomic RNA has a 5' cap lacking 2'-O methylation. We show that pathogenic alphaviruses use secondary structural motifs within the 5' untranslated region (UTR) of their RNA to alter Ifit1 binding and function. Mutations within the 5'-UTR affecting RNA structural elements enabled restriction by or antagonism of Ifit1 in vitro and in vivo. These results identify an evasion mechanism by which viruses use RNA structural motifs to avoid immune restriction.

  8. Who Regulates Whom? An Overview of RNA Granules and Viral Infections

    Directory of Open Access Journals (Sweden)

    Natalia Poblete-Durán

    2016-06-01

    Full Text Available After viral infection, host cells respond by mounting an anti-viral stress response in order to create a hostile atmosphere for viral replication, leading to the shut-off of mRNA translation (protein synthesis and the assembly of RNA granules. Two of these RNA granules have been well characterized in yeast and mammalian cells, stress granules (SGs, which are translationally silent sites of RNA triage and processing bodies (PBs, which are involved in mRNA degradation. This review discusses the role of these RNA granules in the evasion of anti-viral stress responses through virus-induced remodeling of cellular ribonucleoproteins (RNPs.

  9. Interferon Induction by RNA Viruses and Antagonism by Viral Pathogens

    Directory of Open Access Journals (Sweden)

    Yuchen Nan

    2014-12-01

    Full Text Available Interferons are a group of small proteins that play key roles in host antiviral innate immunity. Their induction mainly relies on host pattern recognition receptors (PRR. Host PRR for RNA viruses include Toll-like receptors (TLR and retinoic acid-inducible gene I (RIG-I like receptors (RLR. Activation of both TLR and RLR pathways can eventually lead to the secretion of type I IFNs, which can modulate both innate and adaptive immune responses against viral pathogens. Because of the important roles of interferons, viruses have evolved multiple strategies to evade host TLR and RLR mediated signaling. This review focuses on the mechanisms of interferon induction and antagonism of the antiviral strategy by RNA viruses.

  10. Dynamics of HIV-1 RNA Near the Plasma Membrane during Virus Assembly.

    Science.gov (United States)

    Sardo, Luca; Hatch, Steven C; Chen, Jianbo; Nikolaitchik, Olga; Burdick, Ryan C; Chen, De; Westlake, Christopher J; Lockett, Stephen; Pathak, Vinay K; Hu, Wei-Shau

    2015-11-01

    To increase our understanding of the events that lead to HIV-1 genome packaging, we examined the dynamics of viral RNA and Gag-RNA interactions near the plasma membrane by using total internal reflection fluorescence microscopy. We labeled HIV-1 RNA with a photoconvertible Eos protein via an RNA-binding protein that recognizes stem-loop sequences engineered into the viral genome. Near-UV light exposure causes an irreversible structural change in Eos and alters its emitted fluorescence from green to red. We studied the dynamics of HIV-1 RNA by photoconverting Eos near the plasma membrane, and we monitored the population of photoconverted red-Eos-labeled RNA signals over time. We found that in the absence of Gag, most of the HIV-1 RNAs stayed near the plasma membrane transiently, for a few minutes. The presence of Gag significantly increased the time that RNAs stayed near the plasma membrane: most of the RNAs were still detected after 30 min. We then quantified the proportion of HIV-1 RNAs near the plasma membrane that were packaged into assembling viral complexes. By tagging Gag with blue fluorescent protein, we observed that only a portion, ∼13 to 34%, of the HIV-1 RNAs that reached the membrane were recruited into assembling particles in an hour, and the frequency of HIV-1 RNA packaging varied with the Gag expression level. Our studies reveal the HIV-1 RNA dynamics on the plasma membrane and the efficiency of RNA recruitment and provide insights into the events leading to the generation of infectious HIV-1 virions. Nascent HIV-1 particles assemble on plasma membranes. During the assembly process, HIV-1 RNA genomes must be encapsidated into viral complexes to generate infectious particles. To gain insights into the RNA packaging and virus assembly mechanisms, we labeled and monitored the HIV-1 RNA signals near the plasma membrane. Our results showed that most of the HIV-1 RNAs stayed near the plasma membrane for only a few minutes in the absence of Gag, whereas

  11. Interactions Between HIV-1 Gag and Viral RNA Genome Enhance Virion Assembly

    DEFF Research Database (Denmark)

    Dilley, Kari A; Nikolaitchik, Olga A; Galli, Andrea

    2017-01-01

    between Gag and viral RNA are required for the enhancement of particle production. Taken together, these studies are consistent with our previous hypothesis that specific dimeric viral RNA:Gag interactions are the nucleation event of infectious virion assembly, ensuring that one RNA dimer is packaged......Most HIV-1 virions contain two copies of full-length viral RNA, indicating that genome packaging is efficient and tightly regulated. However, the structural protein Gag is the only component required for the assembly of noninfectious virus-like particles and the viral RNA is dispensable...... in this process. The mechanism that allows HIV-1 to achieve such high efficiency of genome packaging when a packageable viral RNA is not required for virus assembly is currently unknown. In this report, we examined the role of HIV-1 RNA in virus assembly and found that packageable HIV-1 RNA enhances particle...

  12. Meticulous plasma isolation is essential to avoid false low-level viraemia in Roche Cobas HIV-1 viral load assays.

    Science.gov (United States)

    Mortier, Virginie; Vancoillie, Leen; Dauwe, Kenny; Staelens, Delfien; Demecheleer, Els; Schauvliege, Marlies; Dinakis, Sylvie; Van Maerken, Tom; Dessilly, Géraldine; Ruelle, Jean; Verhofstede, Chris

    2017-10-24

    Pre-analytical sample processing is often overlooked as a potential cause of inaccurate assay results. Here we demonstrate how plasma, extracted from standard EDTA-containing blood collection tubes, may contain traces of blood cells consequently resulting in a false low-level HIV-1 viral load when using Roche Cobas HIV-1 assays. The presence of human DNA in Roche Cobas 4800 RNA extracts and in RNA extracts from the Abbott HIV-1 RealTime assay was assessed by quantifying the human albumin gene by means of quantitative PCR. RNA was extracted from plasma samples before and after an additional centrifugation and tested for viral load and DNA contamination. The relation between total DNA content and viral load was defined. Elevated concentrations of genomic DNA were detected in 28 out of 100 Cobas 4800 extracts and were significantly more frequent in samples processed outside of the AIDS Reference Laboratory. An association between genomic DNA presence and spurious low-level viraemia results was demonstrated. Supplementary centrifugation of plasma before RNA extraction eliminated the contamination and the false viraemia. Plasma isolated from standard EDTA-containing blood collection tubes may contain traces of HIV DNA leading to false viral load results above the clinical cutoff. Supplementary centrifugation of plasma before viral load analysis may eliminate the occurrence of this spurious low-level viraemia.

  13. Profile of HIV-1 RNA viral load among HIV-TB co-infected patients in ...

    African Journals Online (AJOL)

    Profile of HIV-1 RNA viral load among HIV-TB co-infected patients in a tertiary health facility in Maiduguri, Northeastern Nigeria. ... This study aims to estimate the HIV-1 RNA viral load and impact of anti TB therapy (ATT) ... HOW TO USE AJOL.

  14. [Investigation of RNA viral genome amplification by multiple displacement amplification technique].

    Science.gov (United States)

    Pang, Zheng; Li, Jian-Dong; Li, Chuan; Liang, Mi-Fang; Li, De-Xin

    2013-06-01

    In order to facilitate the detection of newly emerging or rare viral infectious diseases, a negative-strand RNA virus-severe fever with thrombocytopenia syndrome bunyavirus, and a positive-strand RNA virus-dengue virus, were used to investigate RNA viral genome unspecific amplification by multiple displacement amplification technique from clinical samples. Series of 10-fold diluted purified viral RNA were utilized as analog samples with different pathogen loads, after a series of reactions were sequentially processed, single-strand cDNA, double-strand cDNA, double-strand cDNA treated with ligation without or with supplemental RNA were generated, then a Phi29 DNA polymerase depended isothermal amplification was employed, and finally the target gene copies were detected by real time PCR assays to evaluate the amplification efficiencies of various methods. The results showed that multiple displacement amplification effects of single-strand or double-strand cDNA templates were limited, while the fold increases of double-strand cDNA templates treated with ligation could be up to 6 X 10(3), even 2 X 10(5) when supplemental RNA existed, and better results were obtained when viral RNA loads were lower. A RNA viral genome amplification system using multiple displacement amplification technique was established in this study and effective amplification of RNA viral genome with low load was achieved, which could provide a tool to synthesize adequate viral genome for multiplex pathogens detection.

  15. Nonreplicative RNA Recombination of an Animal Plus-Strand RNA Virus in the Absence of Efficient Translation of Viral Proteins.

    Science.gov (United States)

    Kleine Büning, Maximiliane; Meyer, Denise; Austermann-Busch, Sophia; Roman-Sosa, Gleyder; Rümenapf, Tillmann; Becher, Paul

    2017-04-01

    RNA recombination is a major driving force for the evolution of RNA viruses and is significantly implicated in the adaptation of viruses to new hosts, changes of virulence, as well as in the emergence of new viruses including drug-resistant and escape mutants. However, the molecular details of recombination in animal RNA viruses are only poorly understood. In order to determine whether viral RNA recombination depends on translation of viral proteins, a nonreplicative recombination system was established which is based on cotransfection of cells with synthetic bovine viral diarrhea virus (family Flaviviridae) RNA genome fragments either lacking the internal ribosome entry site required for cap-independent translation or lacking almost the complete polyprotein coding region. The emergence of a number of recombinant viruses demonstrated that IRES-mediated translation of viral proteins is dispensable for efficient recombination and suggests that RNA recombination can occur in the absence of viral proteins. Analyses of 58 independently emerged viruses led to the detection of recombinant genomes with duplications, deletions and insertions in the 5' terminal region of the open reading frame, leading to enlarged core fusion proteins detectable by Western blot analysis. This demonstrates a remarkable flexibility of the pestivirus core protein. Further experiments with capped and uncapped genome fragments containing a luciferase gene for monitoring the level of protein translation revealed that even a ∼1,000-fold enhancement of translation of viral proteins did not increase the frequency of RNA recombination. Taken together, this study highlights that nonreplicative RNA recombination does not require translation of viral proteins. © The Author(s) 2017. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

  16. Nonreplicative RNA Recombination of an Animal Plus-Strand RNA Virus in the Absence of Efficient Translation of Viral Proteins

    Science.gov (United States)

    Kleine Büning, Maximiliane; Meyer, Denise; Austermann-Busch, Sophia; Roman-Sosa, Gleyder; Rümenapf, Tillmann

    2017-01-01

    RNA recombination is a major driving force for the evolution of RNA viruses and is significantly implicated in the adaptation of viruses to new hosts, changes of virulence, as well as in the emergence of new viruses including drug-resistant and escape mutants. However, the molecular details of recombination in animal RNA viruses are only poorly understood. In order to determine whether viral RNA recombination depends on translation of viral proteins, a nonreplicative recombination system was established which is based on cotransfection of cells with synthetic bovine viral diarrhea virus (family Flaviviridae) RNA genome fragments either lacking the internal ribosome entry site required for cap-independent translation or lacking almost the complete polyprotein coding region. The emergence of a number of recombinant viruses demonstrated that IRES-mediated translation of viral proteins is dispensable for efficient recombination and suggests that RNA recombination can occur in the absence of viral proteins. Analyses of 58 independently emerged viruses led to the detection of recombinant genomes with duplications, deletions and insertions in the 5′ terminal region of the open reading frame, leading to enlarged core fusion proteins detectable by Western blot analysis. This demonstrates a remarkable flexibility of the pestivirus core protein. Further experiments with capped and uncapped genome fragments containing a luciferase gene for monitoring the level of protein translation revealed that even a ∼1,000-fold enhancement of translation of viral proteins did not increase the frequency of RNA recombination. Taken together, this study highlights that nonreplicative RNA recombination does not require translation of viral proteins. PMID:28338950

  17. Plasma Viral miRNAs Indicate a High Prevalence of Occult Viral Infections

    Directory of Open Access Journals (Sweden)

    Enrique Fuentes-Mattei

    2017-06-01

    Full Text Available Prevalence of Kaposi sarcoma-associated herpesvirus (KSHV/HHV-8 varies greatly in different populations. We hypothesized that the actual prevalence of KSHV/HHV8 infection in humans is underestimated by the currently available serological tests. We analyzed four independent patient cohorts with post-surgical or post-chemotherapy sepsis, chronic lymphocytic leukemia and post-surgical patients with abdominal surgical interventions. Levels of specific KSHV-encoded miRNAs were measured by reverse transcription-quantitative polymerase chain reaction (RT-qPCR, and KSHV/HHV-8 IgG were measured by immunoassay. We also measured specific miRNAs from Epstein Barr Virus (EBV, a virus closely related to KSHV/HHV-8, and determined the EBV serological status by ELISA for Epstein-Barr nuclear antigen 1 (EBNA-1 IgG. Finally, we identified the viral miRNAs by in situ hybridization (ISH in bone marrow cells. In training/validation settings using independent multi-institutional cohorts of 300 plasma samples, we identified in 78.50% of the samples detectable expression of at least one of the three tested KSHV-miRNAs by RT-qPCR, while only 27.57% of samples were found to be seropositive for KSHV/HHV-8 IgG (P < 0.001. The prevalence of KSHV infection based on miRNAs qPCR is significantly higher than the prevalence determined by seropositivity, and this is more obvious for immuno-depressed patients. Plasma viral miRNAs quantification proved that EBV infection is ubiquitous. Measurement of viral miRNAs by qPCR has the potential to become the “gold” standard method to detect certain viral infections in clinical practice.

  18. Influenza virus gene expression: viral RNA replication in vivo and in vitro

    International Nuclear Information System (INIS)

    Shapiro, G.I.

    1987-01-01

    To develop an overall scheme for the control of influenza virus gene expression, single-stranded M13 DNAs specific for the various genomic segments were used to analyze the synthesis of virus-specific RNAs in infected cells. The results showed that virus infection is divided into two distinct phases. During the early phase, the syntheses of specific virion RNAs (vRNAs), viral mRNAs, and viral proteins were coupled. This phase lasted for 2.5 hours in BHK-21 cells, the time when the rate of synthesis of all the viral mRNAs was maximal. During the late phase, the synthesis of all the vRNAs remained at or near maximum, whereas the rate of synthesis of all the viral mRNAs declined dramatically. Viral mRNA and protein syntheses were also not coupled, as the synthesis of all the viral proteins continued at maximum levels, indicating that protein synthesis during this phase was directed principally by previously synthesized viral mRNAs. Pulses with [ 3 H]uridine and nonaqueous fractionation of cells were used to show that influenza vRNA, like viral mRNAs, are synthesized in the nucleus and efficiently transported to the cytoplasm. In contrast, the full-length transcripts of the vRNAs, the templates for new vRNA synthesis, were synthesized only at early times, and remained sequestered in the nucleus to direct vRNA synthesis throughout infection

  19. Nuclear Imprisonment: Viral Strategies to Arrest Host mRNA Nuclear Export

    Science.gov (United States)

    Kuss, Sharon K.; Mata, Miguel A.; Zhang, Liang; Fontoura, Beatriz M. A.

    2013-01-01

    Viruses possess many strategies to impair host cellular responses to infection. Nuclear export of host messenger RNAs (mRNA) that encode antiviral factors is critical for antiviral protein production and control of viral infections. Several viruses have evolved sophisticated strategies to inhibit nuclear export of host mRNAs, including targeting mRNA export factors and nucleoporins to compromise their roles in nucleo-cytoplasmic trafficking of cellular mRNA. Here, we present a review of research focused on suppression of host mRNA nuclear export by viruses, including influenza A virus and vesicular stomatitis virus, and the impact of this viral suppression on host antiviral responses. PMID:23872491

  20. An Intrinsically Disordered Peptide from Ebola Virus VP35 Controls Viral RNA Synthesis by Modulating Nucleoprotein-RNA Interactions

    Directory of Open Access Journals (Sweden)

    Daisy W. Leung

    2015-04-01

    Full Text Available During viral RNA synthesis, Ebola virus (EBOV nucleoprotein (NP alternates between an RNA-template-bound form and a template-free form to provide the viral polymerase access to the RNA template. In addition, newly synthesized NP must be prevented from indiscriminately binding to noncognate RNAs. Here, we investigate the molecular bases for these critical processes. We identify an intrinsically disordered peptide derived from EBOV VP35 (NPBP, residues 20–48 that binds NP with high affinity and specificity, inhibits NP oligomerization, and releases RNA from NP-RNA complexes in vitro. The structure of the NPBP/ΔNPNTD complex, solved to 3.7 Å resolution, reveals how NPBP peptide occludes a large surface area that is important for NP-NP and NP-RNA interactions and for viral RNA synthesis. Together, our results identify a highly conserved viral interface that is important for EBOV replication and can be targeted for therapeutic development.

  1. An Intrinsically Disordered Peptide from Ebola Virus VP35 Controls Viral RNA Synthesis by Modulating Nucleoprotein-RNA Interactions.

    Science.gov (United States)

    Leung, Daisy W; Borek, Dominika; Luthra, Priya; Binning, Jennifer M; Anantpadma, Manu; Liu, Gai; Harvey, Ian B; Su, Zhaoming; Endlich-Frazier, Ariel; Pan, Juanli; Shabman, Reed S; Chiu, Wah; Davey, Robert A; Otwinowski, Zbyszek; Basler, Christopher F; Amarasinghe, Gaya K

    2015-04-21

    During viral RNA synthesis, Ebola virus (EBOV) nucleoprotein (NP) alternates between an RNA-template-bound form and a template-free form to provide the viral polymerase access to the RNA template. In addition, newly synthesized NP must be prevented from indiscriminately binding to noncognate RNAs. Here, we investigate the molecular bases for these critical processes. We identify an intrinsically disordered peptide derived from EBOV VP35 (NPBP, residues 20-48) that binds NP with high affinity and specificity, inhibits NP oligomerization, and releases RNA from NP-RNA complexes in vitro. The structure of the NPBP/ΔNPNTD complex, solved to 3.7 Å resolution, reveals how NPBP peptide occludes a large surface area that is important for NP-NP and NP-RNA interactions and for viral RNA synthesis. Together, our results identify a highly conserved viral interface that is important for EBOV replication and can be targeted for therapeutic development. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

  2. Novel microRNA-like viral small regulatory RNAs arising during human hepatitis A virus infection.

    Science.gov (United States)

    Shi, Jiandong; Sun, Jing; Wang, Bin; Wu, Meini; Zhang, Jing; Duan, Zhiqing; Wang, Haixuan; Hu, Ningzhu; Hu, Yunzhang

    2014-10-01

    MicroRNAs (miRNAs), including host miRNAs and viral miRNAs, play vital roles in regulating host-virus interactions. DNA viruses encode miRNAs that regulate the viral life cycle. However, it is generally believed that cytoplasmic RNA viruses do not encode miRNAs, owing to inaccessible cellular miRNA processing machinery. Here, we provide a comprehensive genome-wide analysis and identification of miRNAs that were derived from hepatitis A virus (HAV; Hu/China/H2/1982), which is a typical cytoplasmic RNA virus. Using deep-sequencing and in silico approaches, we identified 2 novel virally encoded miRNAs, named hav-miR-1-5p and hav-miR-2-5p. Both of the novel virally encoded miRNAs were clearly detected in infected cells. Analysis of Dicer enzyme silencing demonstrated that HAV-derived miRNA biogenesis is Dicer dependent. Furthermore, we confirmed that HAV mature miRNAs were generated from viral miRNA precursors (pre-miRNAs) in host cells. Notably, naturally derived HAV miRNAs were biologically and functionally active and induced post-transcriptional gene silencing (PTGS). Genomic location analysis revealed novel miRNAs located in the coding region of the viral genome. Overall, our results show that HAV naturally generates functional miRNA-like small regulatory RNAs during infection. This is the first report of miRNAs derived from the coding region of genomic RNA of a cytoplasmic RNA virus. These observations demonstrate that a cytoplasmic RNA virus can naturally generate functional miRNAs, as DNA viruses do. These findings also contribute to improved understanding of host-RNA virus interactions mediated by RNA virus-derived miRNAs. © FASEB.

  3. Intrinsically disordered region of influenza A NP regulates viral genome packaging via interactions with viral RNA and host PI(4,5)P2.

    Science.gov (United States)

    Kakisaka, Michinori; Yamada, Kazunori; Yamaji-Hasegawa, Akiko; Kobayashi, Toshihide; Aida, Yoko

    2016-09-01

    To be incorporated into progeny virions, the viral genome must be transported to the inner leaflet of the plasma membrane (PM) and accumulate there. Some viruses utilize lipid components to assemble at the PM. For example, simian virus 40 (SV40) targets the ganglioside GM1 and human immunodeficiency virus type 1 (HIV-1) utilizes phosphatidylinositol (4,5) bisphosphate [PI(4,5)P2]. Recent studies clearly indicate that Rab11-mediated recycling endosomes are required for influenza A virus (IAV) trafficking of vRNPs to the PM but it remains unclear how IAV vRNP localized or accumulate underneath the PM for viral genome incorporation into progeny virions. In this study, we found that the second intrinsically disordered region (IDR2) of NP regulates two binding steps involved in viral genome packaging. First, IDR2 facilitates NP oligomer binding to viral RNA to form vRNP. Secondly, vRNP assemble by interacting with PI(4,5)P2 at the PM via IDR2. These findings suggest that PI(4,5)P2 functions as the determinant of vRNP accumulation at the PM. Copyright © 2016 Elsevier Inc. All rights reserved.

  4. Discordant CSF/plasma HIV-1 RNA in individuals on virologically suppressive antiretroviral therapy in Western India.

    Science.gov (United States)

    Dravid, Ameet N; Natrajan, Kartik; Kulkarni, Milind M; Saraf, Chinmay K; Mahajan, Uma S; Kore, Sachin D; Rathod, Niranjan M; Mahajan, Umakant S; Wadia, Rustom S

    2018-02-01

    Aim of this study was to estimate the prevalence of cerebrospinal fluid (CSF)/Plasma HIV-1 RNA discordance in virologically suppressed individuals presenting with incident neurologic symptoms.In this retrospective cohort study conducted between March 1, 2009, and March 1, 2017, HIV-1 infected adults exposed to atleast 12 months of antiretroviral therapy (ART) and having plasma viral load (VL) CSF/Plasma HIV-1 RNA discordance by measuring HIV-1 RNA in collected plasma and CSF samples. CSF/plasma HIV-1 RNA discordance was defined as either detectable CSF HIV-1 RNA (VL > 20 copies/mL) with an undetectable plasma RNA (complete viral suppression, VL ≤20 copies/mL) or CSF HIV-1 RNA ≥ 0.5 log10 higher than plasma RNA when plasma VL was between 20 and 1000 copies/mL (low-level viremia, LLV).Out of 1584 virologically suppressed patients, 71 (4.4%) presented with incident neurologic symptoms. Twenty out of 71 (28.2%) patients were diagnosed with CSF/Plasma HIV-1 discordance. Median plasma and CSF VL in patients with discordance was 120 [interquartile range (IQR): CSF HIV-1 genotypic resistance testing was done showed mutations that would compromise efficacy of prescribed ART regimen. Prevalence of CSF/plasma HIV-1 RNA discordance was higher among neurologically symptomatic patients with plasma LLV as compared with those with complete viral suppression (70% vs 11.8%, P CSF/plasma HIV-1 RNA discordance indicates replication of HIV-1 that has adapted to the CNS or has developed antiretroviral drug resistance. Larger studies should be performed to study incidence of discordance in India. This will help in managing patients presenting with neurologic symptoms on suppressive ART with appropriate neuroeffective therapy.

  5. Double Stranded RNA in Human Seminal Plasma

    Directory of Open Access Journals (Sweden)

    Maxim V. Zagoskin

    2017-10-01

    Full Text Available Recently, human semen was shown to contain cell-free nucleic acids, such as DNA, long single stranded RNA, and small RNAs–miRNA and piRNA. The RNAs have been suggested to have potential biological roles as communication molecules between cells and in the temporal and spatial regulation of gene expression in the male reproductive system. Here we demonstrate that human seminal plasma contains a variety of cell-free dsRNAs, describe a robust method to isolate this type of nucleic acid in preparative amounts, and discuss the potential biological roles of these molecules in inheritance. dsRNA plays a role in a variety of biological processes, including gene regulation, is extremely stable and can gain access to cells from the extracellular medium. We suggest that one of the possible functions of dsRNA in human seminal plasma may be to influence human oocytes and therefore, influence the offspring. It also remains possible that these dsRNAs might have potential use as biomarkers for the study of human physiopathological conditions and genetic variation.

  6. Viral RNAi suppressor reversibly binds siRNA to outcompete Dicer and RISC via multiple turnover.

    Science.gov (United States)

    Rawlings, Renata A; Krishnan, Vishalakshi; Walter, Nils G

    2011-04-29

    RNA interference is a conserved gene regulatory mechanism employed by most eukaryotes as a key component of their innate immune response to viruses and retrotransposons. During viral infection, the RNase-III-type endonuclease Dicer cleaves viral double-stranded RNA into small interfering RNAs (siRNAs) 21-24 nucleotides in length and helps load them into the RNA-induced silencing complex (RISC) to guide the cleavage of complementary viral RNA. As a countermeasure, many viruses have evolved viral RNA silencing suppressors (RSS) that tightly, and presumably quantitatively, bind siRNAs to thwart RNA-interference-mediated degradation. Viral RSS proteins also act across kingdoms as potential immunosuppressors in gene therapeutic applications. Here we report fluorescence quenching and electrophoretic mobility shift assays that probe siRNA binding by the dimeric RSS p19 from Carnation Italian Ringspot Virus, as well as by human Dicer and RISC assembly complexes. We find that the siRNA:p19 interaction is readily reversible, characterized by rapid binding [(1.69 ± 0.07) × 10(8) M(-)(1) s(-1)] and marked dissociation (k(off)=0.062 ± 0.002 s(-1)). We also observe that p19 efficiently competes with recombinant Dicer and inhibits the formation of RISC-related assembly complexes found in human cell extract. Computational modeling based on these results provides evidence for the transient formation of a ternary complex between siRNA, human Dicer, and p19. An expanded model of RNA silencing indicates that multiple turnover by reversible binding of siRNAs potentiates the efficiency of the suppressor protein. Our predictive model is expected to be applicable to the dosing of p19 as a silencing suppressor in viral gene therapy. Copyright © 2011 Elsevier Ltd. All rights reserved.

  7. Dried blood spot HIV-1 RNA quantification: A useful tool for viral load monitoring among HIV-infected individuals in India

    Science.gov (United States)

    Neogi, Ujjwal; Gupta, Soham; Rodridges, Rashmi; Sahoo, Pravat Nalini; Rao, Shwetha D.; Rewari, Bharat B.; Shastri, Suresh; De Costa, Ayesha; Shet, Anita

    2012-01-01

    Background & objectives: Monitoring of HIV-infected individuals on antiretroviral treatment (ART) ideally requires periodic viral load measurements to ascertain adequate response to treatment. While plasma viral load monitoring is widely available in high-income settings, it is rarely used in resource-limited regions because of high cost and need for sophisticated sample transport. Dried blood spot (DBS) as source specimens for viral load measurement has shown promise as an alternative to plasma specimens and is likely to be a useful tool for Indian settings. The present study was undertaken to investigate the performance of DBS in HIV-1 RNA quantification against the standard plasma viral load assay. Methods: Between April-June 2011, 130 samples were collected from HIV-1-infected (n=125) and non-infected (n=5) individuals in two district clinics in southern India. HIV-1 RNA quantification was performed from DBS and plasma using Abbott m2000rt system after manual RNA extraction. Statistical analysis included correlation, regression and Bland-Altman analysis. Results: The sensitivity of DBS viral load was 97 per cent with viral loads >3.0 log10 copies/ml. Measurable viral load (>3.0 log 10 copies/ml) results obtained for the 74 paired plasma-DBS samples showed positive correlation between both the assays (r=0.96). For clinically acceptable viral load threshold values of >5,000 copies/ml, Bland-Altman plots showed acceptable limits of agreement (−0.21 to +0.8 log10 copies/ml). The mean difference was 0.29 log10 copies/ml. The cost of DBS was $2.67 lower compared to conventional plasma viral load measurement in the setting Interpretation & conclusions: The significant positive correlation with standard plasma-based assay and lower cost of DBS viral load monitoring suggest that DBS sampling can be a feasible and economical means of viral load monitoring in HIV-infected individual in India and in other resource-limited settings globally. PMID:23391790

  8. Determining mutant spectra of three RNA viral samples using ultra-deep sequencing

    Energy Technology Data Exchange (ETDEWEB)

    Chen, H

    2012-06-06

    RNA viruses have extremely high mutation rates that enable the virus to adapt to new host environments and even jump from one species to another. As part of a viral transmission study, three viral samples collected from naturally infected animals were sequenced using Illumina paired-end technology at ultra-deep coverage. In order to determine the mutant spectra within the viral quasispecies, it is critical to understand the sequencing error rates and control for false positive calls of viral variants (point mutantations). I will estimate the sequencing error rate from two control sequences and characterize the mutant spectra in the natural samples with this error rate.

  9. Homologous SV40 RNA trans-splicing: Special case or prime example of viral RNA trans-splicing?

    Directory of Open Access Journals (Sweden)

    Sushmita Poddar

    2014-06-01

    Full Text Available To date the Simian Virus 40 (SV40 is the only proven example of a virus that recruits the mechanism of RNA trans-splicing to diversify its sequences and gene products. Thereby, two identical viral transcripts are efficiently joined by homologous trans-splicing triggering the formation of a highly transforming 100 kDa super T antigen. Sequences of other viruses including HIV-1 and the human adenovirus type 5 were reported to be involved in heterologous trans-splicing towards cellular or viral sequences but the meaning of these events remains unclear. We computationally and experimentally investigated molecular features associated with viral RNA trans-splicing and identified a common pattern: Viral RNA trans-splicing occurs between strong cryptic or regular viral splice sites and strong regular or cryptic splice sites of the trans-splice partner sequences. The majority of these splice sites are supported by exonic splice enhancers. Splice sites that could compete with the trans-splicing sites for cis-splice reactions are weaker or inexistent. Finally, all but one of the trans-splice reactions seem to be facilitated by one or more complementary binding domains of 11 to 16 nucleotides in length which, however occur with a statistical probability close to one for the given length of the involved sequences. The chimeric RNAs generated via heterologous viral RNA trans-splicing either did not lead to fusion proteins or led to proteins of unknown function. Our data suggest that distinct viral RNAs are highly susceptible to trans-splicing and that heterologous viral trans-splicing, unlike homologous SV40 trans-splicing, represents a chance event.

  10. Clinical value of indicators of cationic proteins, leukocytes myeloperoxidase and fibronectin blood plasma in viral meningitis in children

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    O. G. Kimirilova

    2017-01-01

    Full Text Available Objective: was to establish clinical and diagnostic value of cytochemical indices of peripheral blood leukocytes (cationic protein and myeloperoxidase, fibronectin blood plasma to assess the severity, predict the course and outcome of viral meningitis in children.Subjects and methods. In 450 patients with viral meningitis (enterovirus, arbovirus, parotitic, herpesviral, adenovirus etiology at the age of 14 years, the parameters of the microbicidal system of leukocytes (cation proteins, myeloperoxidase and fibronectin blood plasma were determined. Etiological diagnosis of meningitis was confirmed by release of viral RNA from blood and cerebrospinal fluid by the polymerase chain reaction, enzyme-linked immunosorbent assay (ELISA.The results and conclusion. Found that severe, prolonged duration, lethal outcome of viral meningitis in children are accompanied by sugnificant suppression of cationic proteins, myeloperoxidase, fibronectin blood plasma, maximally expressed in lethal outcomes, compared with the severe form, but with a favorable outcome and control. Settings imbalance cationic proteins, myeloperoxidase, fibronectin blood plasma are objective criteria of the adaptation syndrome that reflects the state of the phagocytosis system in viral meningitis in children and can be considered as additional criteria for predicting the course and outcome of disease.

  11. Hairpin RNA Targeting Multiple Viral Genes Confers Strong Resistance to Rice Black-Streaked Dwarf Virus

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    Fangquan Wang

    2016-05-01

    Full Text Available Rice black-streaked dwarf virus (RBSDV belongs to the genus Fijivirus in the family of Reoviridae and causes severe yield loss in rice-producing areas in Asia. RNA silencing, as a natural defence mechanism against plant viruses, has been successfully exploited for engineering virus resistance in plants, including rice. In this study, we generated transgenic rice lines harbouring a hairpin RNA (hpRNA construct targeting four RBSDV genes, S1, S2, S6 and S10, encoding the RNA-dependent RNA polymerase, the putative core protein, the RNA silencing suppressor and the outer capsid protein, respectively. Both field nursery and artificial inoculation assays of three generations of the transgenic lines showed that they had strong resistance to RBSDV infection. The RBSDV resistance in the segregating transgenic populations correlated perfectly with the presence of the hpRNA transgene. Furthermore, the hpRNA transgene was expressed in the highly resistant transgenic lines, giving rise to abundant levels of 21–24 nt small interfering RNA (siRNA. By small RNA deep sequencing, the RBSDV-resistant transgenic lines detected siRNAs from all four viral gene sequences in the hpRNA transgene, indicating that the whole chimeric fusion sequence can be efficiently processed by Dicer into siRNAs. Taken together, our results suggest that long hpRNA targeting multiple viral genes can be used to generate stable and durable virus resistance in rice, as well as other plant species.

  12. Hairpin RNA Targeting Multiple Viral Genes Confers Strong Resistance to Rice Black-Streaked Dwarf Virus.

    Science.gov (United States)

    Wang, Fangquan; Li, Wenqi; Zhu, Jinyan; Fan, Fangjun; Wang, Jun; Zhong, Weigong; Wang, Ming-Bo; Liu, Qing; Zhu, Qian-Hao; Zhou, Tong; Lan, Ying; Zhou, Yijun; Yang, Jie

    2016-05-11

    Rice black-streaked dwarf virus (RBSDV) belongs to the genus Fijivirus in the family of Reoviridae and causes severe yield loss in rice-producing areas in Asia. RNA silencing, as a natural defence mechanism against plant viruses, has been successfully exploited for engineering virus resistance in plants, including rice. In this study, we generated transgenic rice lines harbouring a hairpin RNA (hpRNA) construct targeting four RBSDV genes, S1, S2, S6 and S10, encoding the RNA-dependent RNA polymerase, the putative core protein, the RNA silencing suppressor and the outer capsid protein, respectively. Both field nursery and artificial inoculation assays of three generations of the transgenic lines showed that they had strong resistance to RBSDV infection. The RBSDV resistance in the segregating transgenic populations correlated perfectly with the presence of the hpRNA transgene. Furthermore, the hpRNA transgene was expressed in the highly resistant transgenic lines, giving rise to abundant levels of 21-24 nt small interfering RNA (siRNA). By small RNA deep sequencing, the RBSDV-resistant transgenic lines detected siRNAs from all four viral gene sequences in the hpRNA transgene, indicating that the whole chimeric fusion sequence can be efficiently processed by Dicer into siRNAs. Taken together, our results suggest that long hpRNA targeting multiple viral genes can be used to generate stable and durable virus resistance in rice, as well as other plant species.

  13. HIV-1 nef suppression by virally encoded microRNA

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    Brisibe Ebiamadon

    2004-12-01

    Full Text Available Abstract Background MicroRNAs (miRNAs are 21~25-nucleotides (nt long and interact with mRNAs to trigger either translational repression or RNA cleavage through RNA interference (RNAi, depending on the degree of complementarity with the target mRNAs. Our recent study has shown that HIV-1 nef dsRNA from AIDS patients who are long-term non-progressors (LTNPs inhibited the transcription of HIV-1. Results Here, we show the possibility that nef-derived miRNAs are produced in HIV-1 persistently infected cells. Furthermore, nef short hairpin RNA (shRNA that corresponded to a predicted nef miRNA (~25 nt, miR-N367 can block HIV-1 Nef expression in vitro and the suppression by shRNA/miR-N367 would be related with low viremia in an LTNP (15-2-2. In the 15-2-2 model mice, the weight loss, which may be rendered by nef was also inhibited by shRNA/miR-N367 corresponding to suppression of nef expression in vivo. Conclusions These data suggest that nef/U3 miRNAs produced in HIV-1-infected cells may suppress both Nef function and HIV-1 virulence through the RNAi pathway.

  14. Antiviral RNA silencing viral counter defense in plants

    NARCIS (Netherlands)

    Bucher, E.C.

    2006-01-01

    The research described in this thesis centres around the mechanism of RNA silencing in relation to virus-host interaction, an area of increasing importance. It shows how this recently disclosed mechanism can be used to produce virus-resistant plants. Based on the activity of the RNA silencing

  15. SearchSmallRNA: a graphical interface tool for the assemblage of viral genomes using small RNA libraries data.

    Science.gov (United States)

    de Andrade, Roberto R S; Vaslin, Maite F S

    2014-03-07

    Next-generation parallel sequencing (NGS) allows the identification of viral pathogens by sequencing the small RNAs of infected hosts. Thus, viral genomes may be assembled from host immune response products without prior virus enrichment, amplification or purification. However, mapping of the vast information obtained presents a bioinformatics challenge. In order to by pass the need of line command and basic bioinformatics knowledge, we develop a mapping software with a graphical interface to the assemblage of viral genomes from small RNA dataset obtained by NGS. SearchSmallRNA was developed in JAVA language version 7 using NetBeans IDE 7.1 software. The program also allows the analysis of the viral small interfering RNAs (vsRNAs) profile; providing an overview of the size distribution and other features of the vsRNAs produced in infected cells. The program performs comparisons between each read sequenced present in a library and a chosen reference genome. Reads showing Hamming distances smaller or equal to an allowed mismatched will be selected as positives and used to the assemblage of a long nucleotide genome sequence. In order to validate the software, distinct analysis using NGS dataset obtained from HIV and two plant viruses were used to reconstruct viral whole genomes. SearchSmallRNA program was able to reconstructed viral genomes using NGS of small RNA dataset with high degree of reliability so it will be a valuable tool for viruses sequencing and discovery. It is accessible and free to all research communities and has the advantage to have an easy-to-use graphical interface. SearchSmallRNA was written in Java and is freely available at http://www.microbiologia.ufrj.br/ssrna/.

  16. VIRmiRNA: a comprehensive resource for experimentally validated viral miRNAs and their targets.

    Science.gov (United States)

    Qureshi, Abid; Thakur, Nishant; Monga, Isha; Thakur, Anamika; Kumar, Manoj

    2014-01-01

    Viral microRNAs (miRNAs) regulate gene expression of viral and/or host genes to benefit the virus. Hence, miRNAs play a key role in host-virus interactions and pathogenesis of viral diseases. Lately, miRNAs have also shown potential as important targets for the development of novel antiviral therapeutics. Although several miRNA and their target repositories are available for human and other organisms in literature, but a dedicated resource on viral miRNAs and their targets are lacking. Therefore, we have developed a comprehensive viral miRNA resource harboring information of 9133 entries in three subdatabases. This includes 1308 experimentally validated miRNA sequences with their isomiRs encoded by 44 viruses in viral miRNA ' VIRMIRNA: ' and 7283 of their target genes in ' VIRMIRTAR': . Additionally, there is information of 542 antiviral miRNAs encoded by the host against 24 viruses in antiviral miRNA ' AVIRMIR': . The web interface was developed using Linux-Apache-MySQL-PHP (LAMP) software bundle. User-friendly browse, search, advanced search and useful analysis tools are also provided on the web interface. VIRmiRNA is the first specialized resource of experimentally proven virus-encoded miRNAs and their associated targets. This database would enhance the understanding of viral/host gene regulation and may also prove beneficial in the development of antiviral therapeutics. Database URL: http://crdd.osdd.net/servers/virmirna. © The Author(s) 2014. Published by Oxford University Press.

  17. Advancing viral RNA structure prediction: measuring the thermodynamics of pyrimidine-rich internal loops.

    Science.gov (United States)

    Phan, Andy; Mailey, Katherine; Saeki, Jessica; Gu, Xiaobo; Schroeder, Susan J

    2017-05-01

    Accurate thermodynamic parameters improve RNA structure predictions and thus accelerate understanding of RNA function and the identification of RNA drug binding sites. Many viral RNA structures, such as internal ribosome entry sites, have internal loops and bulges that are potential drug target sites. Current models used to predict internal loops are biased toward small, symmetric purine loops, and thus poorly predict asymmetric, pyrimidine-rich loops with >6 nucleotides (nt) that occur frequently in viral RNA. This article presents new thermodynamic data for 40 pyrimidine loops, many of which can form UU or protonated CC base pairs. Uracil and protonated cytosine base pairs stabilize asymmetric internal loops. Accurate prediction rules are presented that account for all thermodynamic measurements of RNA asymmetric internal loops. New loop initiation terms for loops with >6 nt are presented that do not follow previous assumptions that increasing asymmetry destabilizes loops. Since the last 2004 update, 126 new loops with asymmetry or sizes greater than 2 × 2 have been measured. These new measurements significantly deepen and diversify the thermodynamic database for RNA. These results will help better predict internal loops that are larger, pyrimidine-rich, and occur within viral structures such as internal ribosome entry sites. © 2017 Phan et al.; Published by Cold Spring Harbor Laboratory Press for the RNA Society.

  18. Comparación de los métodos de cuantificación de carga viral de VIH: COBAS® AmpliPrep/COBAS® TaqMan HIV-1 test, v 2.0, y VERSANT HIV-1 RNA 1.0 Assay (kPCR Comparison of COBAS® AmpliPrep/COBAS® TaqMan HIV-1 test, v 2.0 and VERSANT HIV-1 RNA 1.0 (kPCR assays for HIV-1 plasma viral load

    Directory of Open Access Journals (Sweden)

    María Isabel Múnera-Jaramillo

    2012-03-01

    Full Text Available Objetivo. El propósito del estudio fue evaluar el desempeño del método VERSANTHIV-1RNA 1.0 Assay® (kPCR (Siemens, para la cuantificación de la carga viral en pacientes con VIH-1, en comparación con el método COBAS® AmpliPrep/COBAS TaqMan HIV-1 test®, v2.0 (Roche Diagnostics (CAP/CTM. Métodos. Las muestras fueron tomadas en dos tubos con EDTA, de 60 pacientes remitidos por el médico tratante para pruebas de carga viral como parte de su control de rutina de VIH/sida, y fueron procesadas para la cuantificación del ARN del VIH-1 por ambas técnicas. Se hizo análisis de regresión y se calcularon los coeficientes de correlación de Pearson, y los de correlación y concordancia de Lin. Se evalúo la concordancia entre las dos técnicas mediante el método de Bland-Altman. Resultados. El promedio de la carga viral por el método CAP/CTM fue 3,2±1,4 long10 copias/ml y, por el método kPCR, 3,0±1,3 long10 copias/ml. El 86,7 % de muestras presentó diferencias entre los dos métodos, menores de 0,5 long10 copias/ml, y el 13,3 % presentó diferencias mayores. El coeficiente de correlación de Pearson entre los dos métodos fue de 0,97 (IC95% 0,95-0,99 y el índice kappa ponderado entre los dos métodos en diferentes rangos de concentración, fue de 0,91 (IC95% 0,87-0,96. El promedio de las diferencias entre las mediciones fue 0,22 long10 copias/ml (IC95% -0,45 a 0,89. Conclusión. Las dos técnicas evaluadas fueron comparables, con el método kPCR se observaron resultados más bajos.Objective: The purpose of this study was to evaluate the performance of the kPCR VERSANT (™ 440 HIV-1RNA 3.0 Assay® (Siemens method for the quantification of viral load in HIV-1 patients, compared to the COBAS AmpliPrep/COBASTaqMan HIV-1 test®, v. 2.0 (Roche Diagnostics (CAP/CTM. Methods: Samples were taken in 2 tubes with EDTA, in 60 patients referred by the attending physician for viral load tests as part of their routine control of HIV/AIDS, and were

  19. Viral RNA Silencing Suppression: The Enigma of Bunyavirus NSs Proteins

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    Marcio Hedil

    2016-07-01

    Full Text Available The Bunyaviridae is a family of arboviruses including both plant- and vertebrate-infecting representatives. The Tospovirus genus accommodates plant-infecting bunyaviruses, which not only replicate in their plant host, but also in their insect thrips vector during persistent propagative transmission. For this reason, they are generally assumed to encounter antiviral RNA silencing in plants and insects. Here we present an overview on how tospovirus nonstructural NSs protein counteracts antiviral RNA silencing in plants and what is known so far in insects. Like tospoviruses, members of the related vertebrate-infecting bunyaviruses classified in the genera Orthobunyavirus, Hantavirus and Phlebovirus also code for a NSs protein. However, for none of them RNA silencing suppressor activity has been unambiguously demonstrated in neither vertebrate host nor arthropod vector. The second part of this review will briefly describe the role of these NSs proteins in modulation of innate immune responses in mammals and elaborate on a hypothetical scenario to explain if and how NSs proteins from vertebrate-infecting bunyaviruses affect RNA silencing. If so, why this discovery has been hampered so far.

  20. Viral RNA Silencing Suppression: The Enigma of Bunyavirus NSs Proteins.

    Science.gov (United States)

    Hedil, Marcio; Kormelink, Richard

    2016-07-23

    The Bunyaviridae is a family of arboviruses including both plant- and vertebrate-infecting representatives. The Tospovirus genus accommodates plant-infecting bunyaviruses, which not only replicate in their plant host, but also in their insect thrips vector during persistent propagative transmission. For this reason, they are generally assumed to encounter antiviral RNA silencing in plants and insects. Here we present an overview on how tospovirus nonstructural NSs protein counteracts antiviral RNA silencing in plants and what is known so far in insects. Like tospoviruses, members of the related vertebrate-infecting bunyaviruses classified in the genera Orthobunyavirus, Hantavirus and Phlebovirus also code for a NSs protein. However, for none of them RNA silencing suppressor activity has been unambiguously demonstrated in neither vertebrate host nor arthropod vector. The second part of this review will briefly describe the role of these NSs proteins in modulation of innate immune responses in mammals and elaborate on a hypothetical scenario to explain if and how NSs proteins from vertebrate-infecting bunyaviruses affect RNA silencing. If so, why this discovery has been hampered so far.

  1. Repertoire of bovine miRNA and miRNA-like small regulatory RNAs expressed upon viral infection.

    Directory of Open Access Journals (Sweden)

    Evgeny A Glazov

    Full Text Available MicroRNA (miRNA and other types of small regulatory RNAs play a crucial role in the regulation of gene expression in eukaryotes. Several distinct classes of small regulatory RNAs have been discovered in recent years. To extend the repertoire of small RNAs characterized in mammals and to examine relationship between host miRNA expression and viral infection we used Illumina's ultrahigh throughput sequencing approach. We sequenced three small RNA libraries prepared from cell line derived from the adult bovine kidney under normal conditions and upon infection of the cell line with Bovine herpesvirus 1. We used a bioinformatics approach to distinguish authentic mature miRNA sequences from other classes of small RNAs and short RNA fragments represented in the sequencing data. Using this approach we detected 219 out of 356 known bovine miRNAs and 115 respective miRNA* sequences. In addition we identified five new bovine orthologs of known mammalian miRNAs and discovered 268 new cow miRNAs many of which are not identifiable in other mammalian genomes and thus might be specific to the ruminant lineage. In addition we found seven new bovine mirtron candidates. We also discovered 10 small nucleolar RNA (snoRNA loci that give rise to small RNA with possible miRNA-like function. Results presented in this study extend our knowledge of the biology and evolution of small regulatory RNAs in mammals and illuminate mechanisms of small RNA biogenesis and function. New miRNA sequences and the original sequencing data have been submitted to miRNA repository (miRBase and NCBI GEO archive respectively. We envisage that these resources will facilitate functional annotation of the bovine genome and promote further functional and comparative genomics studies of small regulatory RNA in mammals.

  2. Statistical properties of thermodynamically predicted RNA secondary structures in viral genomes

    Science.gov (United States)

    Spanò, M.; Lillo, F.; Miccichè, S.; Mantegna, R. N.

    2008-10-01

    By performing a comprehensive study on 1832 segments of 1212 complete genomes of viruses, we show that in viral genomes the hairpin structures of thermodynamically predicted RNA secondary structures are more abundant than expected under a simple random null hypothesis. The detected hairpin structures of RNA secondary structures are present both in coding and in noncoding regions for the four groups of viruses categorized as dsDNA, dsRNA, ssDNA and ssRNA. For all groups, hairpin structures of RNA secondary structures are detected more frequently than expected for a random null hypothesis in noncoding rather than in coding regions. However, potential RNA secondary structures are also present in coding regions of dsDNA group. In fact, we detect evolutionary conserved RNA secondary structures in conserved coding and noncoding regions of a large set of complete genomes of dsDNA herpesviruses.

  3. Know Your Enemy: Successful Bioinformatic Approaches to Predict Functional RNA Structures in Viral RNAs

    Science.gov (United States)

    Lim, Chun Shen; Brown, Chris M.

    2018-01-01

    Structured RNA elements may control virus replication, transcription and translation, and their distinct features are being exploited by novel antiviral strategies. Viral RNA elements continue to be discovered using combinations of experimental and computational analyses. However, the wealth of sequence data, notably from deep viral RNA sequencing, viromes, and metagenomes, necessitates computational approaches being used as an essential discovery tool. In this review, we describe practical approaches being used to discover functional RNA elements in viral genomes. In addition to success stories in new and emerging viruses, these approaches have revealed some surprising new features of well-studied viruses e.g., human immunodeficiency virus, hepatitis C virus, influenza, and dengue viruses. Some notable discoveries were facilitated by new comparative analyses of diverse viral genome alignments. Importantly, comparative approaches for finding RNA elements embedded in coding and non-coding regions differ. With the exponential growth of computer power we have progressed from stem-loop prediction on single sequences to cutting edge 3D prediction, and from command line to user friendly web interfaces. Despite these advances, many powerful, user friendly prediction tools and resources are underutilized by the virology community. PMID:29354101

  4. Nuclear Imprisonment: Viral Strategies to Arrest Host mRNA Nuclear Export

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    Beatriz M. A. Fontoura

    2013-07-01

    Full Text Available Viruses possess many strategies to impair host cellular responses to infection. Nuclear export of host messenger RNAs (mRNA that encode antiviral factors is critical for antiviral protein production and control of viral infections. Several viruses have evolved sophisticated strategies to inhibit nuclear export of host mRNAs, including targeting mRNA export factors and nucleoporins to compromise their roles in nucleo-cytoplasmic trafficking of cellular mRNA. Here, we present a review of research focused on suppression of host mRNA nuclear export by viruses, including influenza A virus and vesicular stomatitis virus, and the impact of this viral suppression on host antiviral responses.

  5. Evolution of Tertiary Structure of Viral RNA Dependent Polymerases

    Czech Academy of Sciences Publication Activity Database

    Černý, Jiří; Černá, B.; Valdés, James J.; Grubhoffer, Libor; Růžek, Daniel

    2014-01-01

    Roč. 9, č. 5 (2014), e96070 E-ISSN 1932-6203 R&D Projects: GA ČR GAP502/11/2116; GA ČR GAP302/12/2490; GA MŠk(CZ) EE2.3.30.0032 Institutional support: RVO:60077344 Keywords : Q-BETA replicase * C virus RNA * crystal structure Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 3.234, year: 2014

  6. 1st International Symposium on Stress-Associated RNA Granules in Human Disease and Viral Infection

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    Bruce W. Banfield

    2014-09-01

    Full Text Available In recent years, important linkages have been made between RNA granules and human disease processes. On June 8-10 of this year, we hosted a new symposium, dubbed the 1st International Symposium on Stress-Associated RNA Granules in Human Disease and Viral Infection. This symposium brought together experts from diverse research disciplines ranging from cancer and neuroscience to infectious disease. This report summarizes speaker presentations and highlights current challenges in the field.

  7. Orchestrating the Selection and Packaging of Genomic RNA by Retroviruses: An Ensemble of Viral and Host Factors

    Science.gov (United States)

    Kaddis Maldonado, Rebecca J.; Parent, Leslie J.

    2016-01-01

    Infectious retrovirus particles contain two copies of unspliced viral RNA that serve as the viral genome. Unspliced retroviral RNA is transcribed in the nucleus by the host RNA polymerase II and has three potential fates: (1) it can be spliced into subgenomic messenger RNAs (mRNAs) for the translation of viral proteins; or it can remain unspliced to serve as either (2) the mRNA for the translation of Gag and Gag–Pol; or (3) the genomic RNA (gRNA) that is packaged into virions. The Gag structural protein recognizes and binds the unspliced viral RNA to select it as a genome, which is selected in preference to spliced viral RNAs and cellular RNAs. In this review, we summarize the current state of understanding about how retroviral packaging is orchestrated within the cell and explore potential new mechanisms based on recent discoveries in the field. We discuss the cis-acting elements in the unspliced viral RNA and the properties of the Gag protein that are required for their interaction. In addition, we discuss the role of host factors in influencing the fate of the newly transcribed viral RNA, current models for how retroviruses distinguish unspliced viral mRNA from viral genomic RNA, and the possible subcellular sites of genomic RNA dimerization and selection by Gag. Although this review centers primarily on the wealth of data available for the alpharetrovirus Rous sarcoma virus, in which a discrete RNA packaging sequence has been identified, we have also summarized the cis- and trans-acting factors as well as the mechanisms governing gRNA packaging of other retroviruses for comparison. PMID:27657110

  8. Innate immune restriction and antagonism of viral RNA lacking 2'-O methylation

    Energy Technology Data Exchange (ETDEWEB)

    Hyde, Jennifer L. [Departments of Medicine, Washington University School of Medicine, St Louis., MO 63110 (United States); Diamond, Michael S., E-mail: diamond@borcim.wustl.edu [Departments of Medicine, Washington University School of Medicine, St Louis., MO 63110 (United States); Molecular Microbiology, Washington University School of Medicine, St Louis., MO 63110 (United States); Pathology & Immunology, Washington University School of Medicine, St Louis., MO 63110 (United States); The Center for Human Immunology and Immunotherapy Programs, Washington University School of Medicine, St Louis., MO 63110 (United States)

    2015-05-15

    N-7 and 2′-O methylation of host cell mRNA occurs in the nucleus and results in the generation of cap structures (cap 0, m{sup 7}GpppN; cap 1, m{sup 7}GpppNm) that control gene expression by modulating nuclear export, splicing, turnover, and protein synthesis. Remarkably, RNA cap modification also contributes to mammalian cell host defense as viral RNA lacking 2′-O methylation is sensed and inhibited by IFIT1, an interferon (IFN) stimulated gene (ISG). Accordingly, pathogenic viruses that replicate in the cytoplasm have evolved mechanisms to circumvent IFIT1 restriction and facilitate infection of mammalian cells. These include: (a) generating cap 1 structures on their RNA through cap-snatching or virally-encoded 2′-O methyltransferases, (b) using cap-independent means of translation, or (c) using RNA secondary structural motifs to antagonize IFIT1 binding. This review will discuss new insights as to how specific modifications at the 5′-end of viral RNA modulate host pathogen recognition responses to promote infection and disease.

  9. Physician experience and rates of plasma HIV-1 RNA suppression among illicit drug users: an observational study

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    Sangsari Sassan

    2012-01-01

    Full Text Available Abstract Background Despite the availability of antiretroviral therapy (ART, suboptimal treatment outcomes have been observed among HIV-seropositive illicit drug users. As there is an urgent need to improve responses to antiretroviral therapy among this population, we undertook this study to evaluate the role of physician experience on rates of plasma HIV-1 RNA suppression following initiation of ART. Methods Using data from a community-recruited cohort of HIV-positive illicit drug users, we used Cox proportional hazards regression to model the time to plasma viral HIV RNA Results Between May 1996 and December 2008, 267 individuals initiated ART among whom 227 (85% achieved a plasma HIV RNA Conclusions In this setting of universal HIV/AIDS care, illicit drug users with more experienced physicians exhibited faster rates of plasma viral load suppression. These findings argue for specialized services to help optimize HIV treatment outcomes among this population.

  10. Cooperation of an RNA Packaging Signal and a Viral Envelope Protein in Coronavirus RNA Packaging

    OpenAIRE

    Narayanan, Krishna; Makino, Shinji

    2001-01-01

    Murine coronavirus mouse hepatitis virus (MHV) produces a genome-length mRNA, mRNA 1, and six or seven species of subgenomic mRNAs in infected cells. Among these mRNAs, only mRNA 1 is efficiently packaged into MHV particles. MHV N protein binds to all MHV mRNAs, whereas envelope M protein interacts only with mRNA 1. This M protein-mRNA 1 interaction most probably determines the selective packaging of mRNA 1 into MHV particles. A short cis-acting MHV RNA packaging signal is necessary and suffi...

  11. An RNA Domain Imparts Specificity and Selectivity to a Viral DNA Packaging Motor

    Science.gov (United States)

    Zhao, Wei; Jardine, Paul J.

    2015-01-01

    ABSTRACT During assembly, double-stranded DNA viruses, including bacteriophages and herpesviruses, utilize a powerful molecular motor to package their genomic DNA into a preformed viral capsid. An integral component of the packaging motor in the Bacillus subtilis bacteriophage ϕ29 is a viral genome-encoded pentameric ring of RNA (prohead RNA [pRNA]). pRNA is a 174-base transcript comprised of two domains, domains I and II. Early studies initially isolated a 120-base form (domain I only) that retains high biological activity in vitro; hence, no function could be assigned to domain II. Here we define a role for this domain in the packaging process. DNA packaging using restriction digests of ϕ29 DNA showed that motors with the 174-base pRNA supported the correct polarity of DNA packaging, selectively packaging the DNA left end. In contrast, motors containing the 120-base pRNA had compromised specificity, packaging both left- and right-end fragments. The presence of domain II also provides selectivity in competition assays with genomes from related phages. Furthermore, motors with the 174-base pRNA were restrictive, in that they packaged only one DNA fragment into the head, whereas motors with the 120-base pRNA packaged several fragments into the head, indicating multiple initiation events. These results show that domain II imparts specificity and stringency to the motor during the packaging initiation events that precede DNA translocation. Heteromeric rings of pRNA demonstrated that one or two copies of domain II were sufficient to impart this selectivity/stringency. Although ϕ29 differs from other double-stranded DNA phages in having an RNA motor component, the function provided by pRNA is carried on the motor protein components in other phages. IMPORTANCE During virus assembly, genome packaging involves the delivery of newly synthesized viral nucleic acid into a protein shell. In the double-stranded DNA phages and herpesviruses, this is accomplished by a powerful

  12. An RNA Domain Imparts Specificity and Selectivity to a Viral DNA Packaging Motor.

    Science.gov (United States)

    Zhao, Wei; Jardine, Paul J; Grimes, Shelley

    2015-12-01

    During assembly, double-stranded DNA viruses, including bacteriophages and herpesviruses, utilize a powerful molecular motor to package their genomic DNA into a preformed viral capsid. An integral component of the packaging motor in the Bacillus subtilis bacteriophage ϕ29 is a viral genome-encoded pentameric ring of RNA (prohead RNA [pRNA]). pRNA is a 174-base transcript comprised of two domains, domains I and II. Early studies initially isolated a 120-base form (domain I only) that retains high biological activity in vitro; hence, no function could be assigned to domain II. Here we define a role for this domain in the packaging process. DNA packaging using restriction digests of ϕ29 DNA showed that motors with the 174-base pRNA supported the correct polarity of DNA packaging, selectively packaging the DNA left end. In contrast, motors containing the 120-base pRNA had compromised specificity, packaging both left- and right-end fragments. The presence of domain II also provides selectivity in competition assays with genomes from related phages. Furthermore, motors with the 174-base pRNA were restrictive, in that they packaged only one DNA fragment into the head, whereas motors with the 120-base pRNA packaged several fragments into the head, indicating multiple initiation events. These results show that domain II imparts specificity and stringency to the motor during the packaging initiation events that precede DNA translocation. Heteromeric rings of pRNA demonstrated that one or two copies of domain II were sufficient to impart this selectivity/stringency. Although ϕ29 differs from other double-stranded DNA phages in having an RNA motor component, the function provided by pRNA is carried on the motor protein components in other phages. During virus assembly, genome packaging involves the delivery of newly synthesized viral nucleic acid into a protein shell. In the double-stranded DNA phages and herpesviruses, this is accomplished by a powerful molecular motor

  13. Multi-resistance strategy for viral diseases and short hairpin RNA verification method in pigs

    Directory of Open Access Journals (Sweden)

    Jong-nam Oh

    2018-04-01

    Full Text Available Objective Foot and mouth disease (FMD and porcine reproductive and respiratory syndrome (PRRS are major diseases that interrupt porcine production. Because they are viral diseases, vaccinations are of only limited effectiveness in preventing outbreaks. To establish an alternative multi-resistant strategy against FMD virus (FMDV and PRRS virus (PRRSV, the present study introduced two genetic modification techniques to porcine cells. Methods First, cluster of differentiation 163 (CD163, the PRRSV viral receptor, was edited with the clustered regularly interspaced short palindromic repeats-CRISPR-associated protein 9 technique. The CD163 gene sequences of edited cells and control cells differed. Second, short hairpin RNA (shRNAs were integrated into the cells. The shRNAs, targeting the 3D gene of FMDV and the open reading frame 7 (ORF7 gene of PRRSV, were transferred into fibroblasts. We also developed an in vitro shRNA verification method with a target gene expression vector. Results shRNA activity was confirmed in vitro with vectors that expressed the 3D and ORF7 genes in the cells. Cells containing shRNAs showed lower transcript levels than cells with only the expression vectors. The shRNAs were integrated into CD163-edited cells to combine the two techniques, and the viral genes were suppressed in these cells. Conclusion We established a multi-resistant strategy against viral diseases and an in vitro shRNA verification method.

  14. Repression of RNA polymerase by the archaeo-viral regulator ORF145/RIP

    DEFF Research Database (Denmark)

    Sheppard, Carol; Blombach, Fabian; Belsom, Adam

    2016-01-01

    Little is known about how archaeal viruses perturb the transcription machinery of their hosts. Here we provide the first example of an archaeo-viral transcription factor that directly targets the host RNA polymerase (RNAP) and efficiently represses its activity. ORF145 from the temperate Acidianus...

  15. Seminal Plasma HIV-1 RNA Concentration Is Strongly Associated with Altered Levels of Seminal Plasma Interferon-γ, Interleukin-17, and Interleukin-5

    Science.gov (United States)

    Hoffman, Jennifer C.; Anton, Peter A.; Baldwin, Gayle Cocita; Elliott, Julie; Anisman-Posner, Deborah; Tanner, Karen; Grogan, Tristan; Elashoff, David; Sugar, Catherine; Yang, Otto O.

    2014-01-01

    Abstract Seminal plasma HIV-1 RNA level is an important determinant of the risk of HIV-1 sexual transmission. We investigated potential associations between seminal plasma cytokine levels and viral concentration in the seminal plasma of HIV-1-infected men. This was a prospective, observational study of paired blood and semen samples from 18 HIV-1 chronically infected men off antiretroviral therapy. HIV-1 RNA levels and cytokine levels in seminal plasma and blood plasma were measured and analyzed using simple linear regressions to screen for associations between cytokines and seminal plasma HIV-1 levels. Forward stepwise regression was performed to construct the final multivariate model. The median HIV-1 RNA concentrations were 4.42 log10 copies/ml (IQR 2.98, 4.70) and 2.96 log10 copies/ml (IQR 2, 4.18) in blood and seminal plasma, respectively. In stepwise multivariate linear regression analysis, blood HIV-1 RNA level (pplasma HIV-1 RNA level. After controlling for blood HIV-1 RNA level, seminal plasma HIV-1 RNA level was positively associated with interferon (IFN)-γ (p=0.03) and interleukin (IL)-17 (p=0.03) and negatively associated with IL-5 (p=0.0007) in seminal plasma. In addition to blood HIV-1 RNA level, cytokine profiles in the male genital tract are associated with HIV-1 RNA levels in semen. The Th1 and Th17 cytokines IFN-γ and IL-17 are associated with increased seminal plasma HIV-1 RNA, while the Th2 cytokine IL-5 is associated with decreased seminal plasma HIV-1 RNA. These results support the importance of genital tract immunomodulation in HIV-1 transmission. PMID:25209674

  16. A SELEX-screened aptamer of human hepatitis B virus RNA encapsidation signal suppresses viral replication.

    Directory of Open Access Journals (Sweden)

    Hui Feng

    Full Text Available BACKGROUND: The specific interaction between hepatitis B virus (HBV polymerase (P protein and the ε RNA stem-loop on pregenomic (pg RNA is crucial for viral replication. It triggers both pgRNA packaging and reverse transcription and thus represents an attractive antiviral target. RNA decoys mimicking ε in P protein binding but not supporting replication might represent novel HBV inhibitors. However, because generation of recombinant enzymatically active HBV polymerase is notoriously difficult, such decoys have as yet not been identified. METHODOLOGY/PRINCIPAL FINDINGS: Here we used a SELEX approach, based on a new in vitro reconstitution system exploiting a recombinant truncated HBV P protein (miniP, to identify potential ε decoys in two large ε RNA pools with randomized upper stem. Selection of strongly P protein binding RNAs correlated with an unexpected strong enrichment of A residues. Two aptamers, S6 and S9, displayed particularly high affinity and specificity for miniP in vitro, yet did not support viral replication when part of a complete HBV genome. Introducing S9 RNA into transiently HBV producing HepG2 cells strongly suppressed pgRNA packaging and DNA synthesis, indicating the S9 RNA can indeed act as an ε decoy that competitively inhibits P protein binding to the authentic ε signal on pgRNA. CONCLUSIONS/SIGNIFICANCE: This study demonstrates the first successful identification of human HBV ε aptamers by an in vitro SELEX approach. Effective suppression of HBV replication by the S9 aptamer provides proof-of-principle for the ability of ε decoy RNAs to interfere with viral P-ε complex formation and suggests that S9-like RNAs may further be developed into useful therapeutics against chronic hepatitis B.

  17. A viral microRNA down-regulates multiple cell cycle genes through mRNA 5'UTRs.

    Directory of Open Access Journals (Sweden)

    Finn Grey

    2010-06-01

    Full Text Available Global gene expression data combined with bioinformatic analysis provides strong evidence that mammalian miRNAs mediate repression of gene expression primarily through binding sites within the 3' untranslated region (UTR. Using RNA induced silencing complex immunoprecipitation (RISC-IP techniques we have identified multiple cellular targets for a human cytomegalovirus (HCMV miRNA, miR-US25-1. Strikingly, this miRNA binds target sites primarily within 5'UTRs, mediating significant reduction in gene expression. Intriguingly, many of the genes targeted by miR-US25-1 are associated with cell cycle control, including cyclin E2, BRCC3, EID1, MAPRE2, and CD147, suggesting that miR-US25-1 is targeting genes within a related pathway. Deletion of miR-US25-1 from HCMV results in over expression of cyclin E2 in the context of viral infection. Our studies demonstrate that a viral miRNA mediates translational repression of multiple cellular genes by targeting mRNA 5'UTRs.

  18. Terminal structures of West Nile virus genomic RNA and their interactions with viral NS5 protein

    International Nuclear Information System (INIS)

    Dong Hongping; Zhang Bo; Shi Peiyong

    2008-01-01

    Genome cyclization is essential for flavivirus replication. We used RNases to probe the structures formed by the 5'-terminal 190 nucleotides and the 3'-terminal 111 nucleotides of the West Nile virus (WNV) genomic RNA. When analyzed individually, the two RNAs adopt stem-loop structures as predicted by the thermodynamic-folding program. However, when mixed together, the two RNAs form a duplex that is mediated through base-pairings of two sets of RNA elements (5'CS/3'CSI and 5'UAR/3'UAR). Formation of the RNA duplex facilitates a conformational change that leaves the 3'-terminal nucleotides of the genome (position - 8 to - 16) to be single-stranded. Viral NS5 binds specifically to the 5'-terminal stem-loop (SL1) of the genomic RNA. The 5'SL1 RNA structure is essential for WNV replication. The study has provided further evidence to suggest that flavivirus genome cyclization and NS5/5'SL1 RNA interaction facilitate NS5 binding to the 3' end of the genome for the initiation of viral minus-strand RNA synthesis

  19. Rubella virus capsid protein modulation of viral genomic and subgenomic RNA synthesis

    International Nuclear Information System (INIS)

    Tzeng, W.-P.; Frey, Teryl K.

    2005-01-01

    The ratio of the subgenomic (SG) to genome RNA synthesized by rubella virus (RUB) replicons expressing the green fluorescent protein reporter gene (RUBrep/GFP) is substantially higher than the ratio of these species synthesized by RUB (4.3 for RUBrep/GFP vs. 1.3-1.4 for RUB). It was hypothesized that this modulation of the viral RNA synthesis was by one of the virus structural protein genes and it was found that introduction of the capsid (C) protein gene into the replicons as an in-frame fusion with GFP resulted in an increase of genomic RNA production (reducing the SG/genome RNA ratio), confirming the hypothesis and showing that the C gene was the moiety responsible for the modulation effect. The N-terminal one-third of the C gene was required for the effect of be exhibited. A similar phenomenon was not observed with the replicons of Sindbis virus, a related Alphavirus. Interestingly, modulation was not observed when RUBrep/GFP was co-transfected with either other RUBrep or plasmid constructs expressing the C gene, demonstrating that modulation could occur only when the C gene was provided in cis. Mutations that prevented translation of the C protein failed to modulate RNA synthesis, indicating that the C protein was the moiety responsible for modulation; consistent with this conclusion, modulation of RNA synthesis was maintained when synonymous codon mutations were introduced at the 5' end of the C gene that changed the C gene sequence without altering the amino acid sequence of the C protein. These results indicate that C protein translated in proximity of viral replication complexes, possibly from newly synthesized SG RNA, participate in regulating the replication of viral RNA

  20. A viral suppressor protein inhibits host RNA silencing by hooking up with Argonautes

    KAUST Repository

    Jin, Hailing; Zhu, Jian-Kang

    2010-01-01

    RNA viruses are particularly vulnerable to RNAi-based defenses in the host, and thus have evolved specific proteins, known as viral suppressors of RNA silencing (VSRs), as a counterdefense. In this issue of Genes & Development, Azevedo and colleagues (pp. 904-915) discovered that P38, the VSR of Turnip crinkle virus, uses its glycine/tryptophane (GW) motifs as an ARGONAUTE (AGO) hook to attract and disarm the host's essential effector of RNA silencing. Several GW motif-containing cellular proteins are known to be important partners of AGOs in RNA silencing effector complexes in yeast, plants, and animals. The GW motif appears to be a versatile and effective tool for regulating the activities of RNA silencing pathways, and the use of GW mimicry to compete for and inhibit host AGOs may be a strategy used by many pathogens to counteract host RNAi-based defenses. © 2010 by Cold Spring Harbor Laboratory Press.

  1. A viral suppressor protein inhibits host RNA silencing by hooking up with Argonautes

    KAUST Repository

    Jin, Hailing

    2010-05-01

    RNA viruses are particularly vulnerable to RNAi-based defenses in the host, and thus have evolved specific proteins, known as viral suppressors of RNA silencing (VSRs), as a counterdefense. In this issue of Genes & Development, Azevedo and colleagues (pp. 904-915) discovered that P38, the VSR of Turnip crinkle virus, uses its glycine/tryptophane (GW) motifs as an ARGONAUTE (AGO) hook to attract and disarm the host\\'s essential effector of RNA silencing. Several GW motif-containing cellular proteins are known to be important partners of AGOs in RNA silencing effector complexes in yeast, plants, and animals. The GW motif appears to be a versatile and effective tool for regulating the activities of RNA silencing pathways, and the use of GW mimicry to compete for and inhibit host AGOs may be a strategy used by many pathogens to counteract host RNAi-based defenses. © 2010 by Cold Spring Harbor Laboratory Press.

  2. A viral suppressor of RNA silencing inhibits ARGONAUTE 1 function by precluding target RNA binding to pre-assembled RISC.

    Science.gov (United States)

    Kenesi, Erzsébet; Carbonell, Alberto; Lózsa, Rita; Vértessy, Beáta; Lakatos, Lóránt

    2017-07-27

    In most eukaryotes, RNA silencing is an adaptive immune system regulating key biological processes including antiviral defense. To evade this response, viruses of plants, worms and insects have evolved viral suppressors of RNA silencing proteins (VSRs). Various VSRs, such as P1 from Sweet potato mild mottle virus (SPMMV), inhibit the activity of RNA-induced silencing complexes (RISCs) including an ARGONAUTE (AGO) protein loaded with a small RNA. However, the specific mechanisms explaining this class of inhibition are unknown. Here, we show that SPMMV P1 interacts with AGO1 and AGO2 from Arabidopsis thaliana, but solely interferes with AGO1 function. Moreover, a mutational analysis of a newly identified zinc finger domain in P1 revealed that this domain could represent an effector domain as it is required for P1 suppressor activity but not for AGO1 binding. Finally, a comparative analysis of the target RNA binding capacity of AGO1 in the presence of wild-type or suppressor-defective P1 forms revealed that P1 blocks target RNA binding to AGO1. Our results describe the negative regulation of RISC, the small RNA containing molecular machine. © The Author(s) 2017. Published by Oxford University Press on behalf of Nucleic Acids Research.

  3. Inhibition of Poliovirus-Induced Cleavage of Cellular Protein PCBP2 Reduces the Levels of Viral RNA Replication

    Science.gov (United States)

    Chase, Amanda J.; Daijogo, Sarah

    2014-01-01

    ABSTRACT Due to their small genome size, picornaviruses must utilize host proteins to mediate cap-independent translation and viral RNA replication. The host RNA-binding protein poly(rC) binding protein 2 (PCBP2) is involved in both processes in poliovirus infected cells. It has been shown that the viral proteinase 3CD cleaves PCBP2 and contributes to viral translation inhibition. However, cleaved PCBP2 remains active in viral RNA replication. This would suggest that both cleaved and intact forms of PCBP2 have a role in the viral RNA replication cycle. The picornavirus genome must act as a template for both translation and RNA replication. However, a template that is actively being translated cannot function as a template for RNA replication, suggesting that there is a switch in template usage from translation to RNA replication. We demonstrate that the cleavage of PCBP2 by the poliovirus 3CD proteinase is a necessary step for efficient viral RNA replication and, as such, may be important for mediating a switch in template usage from translation to RNA replication. IMPORTANCE Poliovirus, like all positive-strand RNA viruses that replicate in the cytoplasm of eukaryotic cells, uses its genomic RNA as a template for both viral protein synthesis and RNA replication. Given that these processes cannot occur simultaneously on the same template, poliovirus has evolved a mechanism(s) to facilitate the switch from using templates for translation to using them for RNA synthesis. This study explores one possible scenario for how the virus alters the functions of a host cell RNA binding protein to mediate, in part, this important transition. PMID:24371074

  4. Viral Small-RNA Analysis of Bombyx mori Larval Midgut during Persistent and Pathogenic Cytoplasmic Polyhedrosis Virus Infection

    OpenAIRE

    Zografidis, Aris; Van Nieuwerburgh, Filip; Kolliopoulou, Anna; Apostolou-Karampelis, Konstantinos; Head, Steven R.; Deforce, Dieter; Smagghe, Guy; Swevers, Luc

    2015-01-01

    The lepidopteran innate immune response against RNA viruses remains poorly understood, while in other insects several studies have highlighted an essential role for the exo-RNAi pathway in combating viral infection. Here, by using deep-sequencing technology for viral small-RNA (vsRNA) assessment, we provide evidence that exo-RNAi is operative in the silkworm Bombyx mori against both persistent and pathogenic infection of B. mori cytoplasmic polyhedrosis virus (BmCPV) which is characterized by...

  5. Accessory factors of cytoplasmic viral RNA sensors required for antiviral innate immune response

    Directory of Open Access Journals (Sweden)

    Hiroyuki eOshiumi

    2016-05-01

    Full Text Available Type I interferon (IFN induces many antiviral factors in host cells. RIG-I-like receptors (RLRs are cytoplasmic viral RNA sensors that trigger the signal to induce the innate immune response that includes type I IFN production. RIG-I and MDA5 are RLRs that form nucleoprotein filaments along viral double-stranded RNA, resulting in the activation of MAVS adaptor molecule. The MAVS protein forms a prion-like aggregation structure, leading to type I IFN production. RIG-I and MDA5 undergo post-translational modification. TRIM25 and Riplet ubiquitin ligases deliver a K63-linked polyubiquitin moiety to the RIG-I N-terminal caspase activation and recruitment domains (CARDs and C-terminal region; the polyubiquitin chain then stabilizes the two-CARD tetramer structure required for MAVS assembly. MDA5 activation is regulated by phosphorylation. RIOK3 is a protein kinase that phosphorylates the MDA5 protein in a steady state, and PP1α/γ dephosphorylate this protein, resulting in its activation. RIG-I and MDA5 require cytoplasmic RNA helicases for their efficient activation. LGP2, another RLR, is an RNA helicase involved in RLR signaling. This protein does not possess N-terminal CARDs and thus cannot trigger downstream signaling by itself. Recent studies have revealed that this protein modulates MDA5 filament formation, resulting in enhanced type I IFN production. Several other cytoplasmic RNA helicases are involved in RLR signaling. DDX3, DHX29, DHX36, and DDX60 RNA helicases have been reported to be involved in RLR-mediated type I IFN production after viral infection. However, the underlying mechanism is largely unknown. Future studies are required to reveal the role of RNA helicases in the RLR signaling pathway.

  6. In situ hybridization studies of hepatitis A viral RNA in patients with acute hepatitis A

    Energy Technology Data Exchange (ETDEWEB)

    Taylor, M; Goldin, R D; Ladva, S [Department of Histopathology, St. Mary' s Hospital Medical School, Imperial College of Science, Technology and Medicine, London (United Kingdom); Scheuer, P J [Department of Histopathology, Royal Free Hospital and School of Medicine, London (United Kingdom); Thomas, H C [Department of Medicine, St. Mary' s Hospital Medical School, Imperial College of Science, Technology and Medicine, London (United Kingdom)

    1994-01-01

    In situ hybridization with oligonucleotide probes has been used to localise hepatitis A virus RNA genomic sequences in formalin-fixed and routinely processed human liver biopsies from three patients. Using radiolabelled Sulphur-35 antisense probes, viral genomic sequences were found in all three cases, but signal intensity was greatest in cases 1 and 2 with fulminant hepatitis, and was minimal in the third case of resolving hepatitis biopsied 2 months after acute illness. Localisation showed the viral RNA to be present in hepatocytes, sinusoidal cells and inflammatory cells in and around the portal tracts. Both cases showed signal in similar cell types, but the distribution of staining was predominantly periportal in case 1, whereas lobular staining was more apparent in case 2. Hybridization with sense polarity probes failed to detect any evidence of replicative intermediates of antigenomic viral RNA. The presence of hepatitis A RNA in phagocytic cells was confirmed using immunohistochemistryfor a macrophage marker, CD68, combined with in situ hybridization. In all cases the signal was predominantly cytoplasmic, and this was confirmed with the use of tritiated probes. (au).

  7. In situ hybridization studies of hepatitis A viral RNA in patients with acute hepatitis A

    International Nuclear Information System (INIS)

    Taylor, M.; Goldin, R.D.; Ladva, S.; Scheuer, P.J.; Thomas, H.C.

    1994-01-01

    In situ hybridization with oligonucleotide probes has been used to localise hepatitis A virus RNA genomic sequences in formalin-fixed and routinely processed human liver biopsies from three patients. Using radiolabelled Sulphur-35 antisense probes, viral genomic sequences were found in all three cases, but signal intensity was greatest in cases 1 and 2 with fulminant hepatitis, and was minimal in the third case of resolving hepatitis biopsied 2 months after acute illness. Localisation showed the viral RNA to be present in hepatocytes, sinusoidal cells and inflammatory cells in and around the portal tracts. Both cases showed signal in similar cell types, but the distribution of staining was predominantly periportal in case 1, whereas lobular staining was more apparent in case 2. Hybridization with sense polarity probes failed to detect any evidence of replicative intermediates of antigenomic viral RNA. The presence of hepatitis A RNA in phagocytic cells was confirmed using immunohistochemistryfor a macrophage marker, CD68, combined with in situ hybridization. In all cases the signal was predominantly cytoplasmic, and this was confirmed with the use of tritiated probes. (au)

  8. Undetectable plasma viral load predicts normal survival in HIV-2-infected people in a West African village

    Directory of Open Access Journals (Sweden)

    Ricard Dominique

    2010-05-01

    Full Text Available Abstract Background There have been no previous studies of the long-term survival and temporal changes in plasma viral load among HIV-2 infected subjects. Methods 133 HIV-2 infected and 158 HIV-uninfected subjects from a rural area in North-west Guinea-Bissau, West Africa were enrolled into a prospective cohort study in 1991 and followed-up to mid-2009. Data were collected on four occasions during that period on HIV antibodies, CD4% and HIV-2 plasma viral load. Results Median age (interquartile range [IQR] of HIV-2 infected subjects at time of enrollment was 47 (36, 60 years, similar to that of HIV-uninfected control subjects, 49 (38, 62 (p = 0.4. Median (IQR plasma viral load and CD4 percentage were 347 (50, 4,300 copies/ml and 29 (22, 35 respectively. Overall loss to follow-up to assess vital status was small, at 6.7% and 6.3% for HIV-2 infected and uninfected subjects respectively. An additional 17 (12.8% and 16 (10.1% of HIV-2 infected and uninfected subjects respectively were censored during follow-up due to infection with HIV-1. The mortality rate per 100 person-years (95% CI was 4.5 (3.6, 5.8 among HIV-2 infected subjects compared to 2.1 (1.6, 2.9 among HIV-uninfected (age-sex adjusted rate ratio 1.9 (1.3, 2.8, p Viral load measurements were available for 98%, 78%, 77% and 61% HIV-2 infected subjects who were alive and had not become super-infected with HIV-1, in 1991, 1996, 2003 and 2006 respectively. Median plasma viral load (RNA copies per ml (IQR did not change significantly over time, being 150 (50, 1,554; n = 77 in 1996, 203 (50, 2,837; n = 47 in 2003 and 171 (50, 497; n = 31 in 2006. Thirty seven percent of HIV-2 subjects had undetectable viraemia ( Conclusions A substantial proportion of HIV-2 infected subjects in this cohort have stable plasma viral load, and those with an undetectable viral load (37% at study entry had a normal survival rate. However, the sequential laboratory findings need to be interpreted with caution given

  9. Antiretroviral-treated HIV-1 patients can harbour resistant viruses in CSF despite an undetectable viral load in plasma.

    Science.gov (United States)

    Soulie, Cathia; Grudé, Maxime; Descamps, Diane; Amiel, Corinne; Morand-Joubert, Laurence; Raymond, Stéphanie; Pallier, Coralie; Bellecave, Pantxika; Reigadas, Sandrine; Trabaud, Mary-Anne; Delaugerre, Constance; Montes, Brigitte; Barin, Francis; Ferré, Virginie; Jeulin, Hélène; Alloui, Chakib; Yerly, Sabine; Signori-Schmuck, Anne; Guigon, Aurélie; Fafi-Kremer, Samira; Haïm-Boukobza, Stéphanie; Mirand, Audrey; Maillard, Anne; Vallet, Sophie; Roussel, Catherine; Assoumou, Lambert; Calvez, Vincent; Flandre, Philippe; Marcelin, Anne-Geneviève

    2017-08-01

    HIV therapy reduces the CSF HIV RNA viral load (VL) and prevents disorders related to HIV encephalitis. However, these brain disorders may persist in some cases. A large population of antiretroviral-treated patients who had a VL > 1.7 log 10 copies/mL in CSF with detectable or undetectable VL in plasma associated with cognitive impairment was studied, in order to characterize discriminatory factors of these two patient populations. Blood and CSF samples were collected at the time of neurological disorders for 227 patients in 22 centres in France and 1 centre in Switzerland. Genotypic HIV resistance tests were performed on CSF. The genotypic susceptibility score was calculated according to the last Agence Nationale de Recherche sur le Sida et les hépatites virales Action Coordonnée 11 (ANRS AC11) genotype interpretation algorithm. Among the 227 studied patients with VL > 1.7 log 10 copies/mL in CSF, 195 had VL detectable in plasma [median (IQR) HIV RNA was 3.7 (2.7-4.7) log 10 copies/mL] and 32 had discordant VL in plasma (VL plasma compared with patients with plasma VL > 1.7 log 10 copies/mL. Resistance to antiretrovirals was observed in CSF for the two groups of patients. Fourteen percent of this population of patients with cognitive impairment and detectable VL in CSF had well controlled VL in plasma. Thus, it is important to explore CSF HIV (VL and genotype) even if the HIV VL is controlled in plasma because HIV resistance may be observed. © The Author 2017. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  10. A viral microRNA functions as an ortholog of cellular miR-155

    Science.gov (United States)

    Gottwein, Eva; Mukherjee, Neelanjan; Sachse, Christoph; Frenzel, Corina; Majoros, William H.; Chi, Jen-Tsan A.; Braich, Ravi; Manoharan, Muthiah; Soutschek, Jürgen; Ohler, Uwe; Cullen, Bryan R.

    2008-01-01

    All metazoan eukaryotes express microRNAs (miRNAs), ∼22 nt regulatory RNAs that can repress the expression of mRNAs bearing complementary sequences1. Several DNA viruses also express miRNAs in infected cells, suggesting a role in viral replication and pathogenesis2. While specific viral miRNAs have been shown to autoregulate viral mRNAs3,4 or downregulate cellular mRNAs5,6, the function of the majority of viral miRNAs remains unknown. Here, we report that the miR-K12−11 miRNA encoded by Kaposi's Sarcoma Associated Herpesvirus (KSHV) shows significant homology to cellular miR-155, including the entire miRNA “seed” region7. Using a range of assays, we demonstrate that expression of physiological levels of miR-K12−11 or miR-155 results in the downregulation of an extensive set of common mRNA targets, including genes with known roles in cell growth regulation. Our findings indicate that viral miR-K12−11 functions as an ortholog of cellular miR-155 and has likely evolved to exploit a pre-existing gene regulatory pathway in B-cells. Moreover, the known etiological role of miR-155 in B-cell transformation8-10 suggests that miR-K12−11 may contribute to the induction of KSHV-positive B-cell tumors in infected patients. PMID:18075594

  11. Characterization of a defective interfering RNA that contains a mosaic of a plant viral genome

    Energy Technology Data Exchange (ETDEWEB)

    Morris, T.J.; Jackson, A.O.

    1991-01-01

    Our lab was the first to describe and characterize a defective interfering RNA (DI RNAs or DIs) in association with a small RNA plant virus. The features of the DIs that we discovered in infections of tomato bushy stunt virus were compatible with the properties of DIs identified in many animal virus infections. Animal virologists have generally recognized the importance of studying DIs because they are invaluable tools for identifying cis-acting sequences important in virus multiplication and because they offer the opportunity to elucidate mechanisms involved in viral persistence and disease attenuation. Hence our discovery offered a comparably valuable tool for use in plant virus studies for the first time. Since then, we have also discovered the second example of plant viral DI RNAs associated with turnip crinkle virus (TCV), a virus structurally related to TBSV. We proposed a thorough characterization of this unique class of symptom modulating RNAs with the overall objective of identifying viral RNA nucleotide, sequences involved in such fundamental processes as virus replication and encapsidation as well as the degree of symptom expression resulting from the viral-DI-host interaction. The proposed research focused on the molecular characterization of the DI RNAs and the helper virus. We had demonstrated that the DIs were collinear deletion mutants of the genome of a cherry strain of tomato bushy stunt virus (TBSV). We had also shown that these low molecular weight RNAs interfered with the helper plant virus and modulated disease expression by preventing the development of a lethal necrotic disease in susceptible host plants. We also suggested that by exploring the mechanisms associated with the symptom attenuation effect, we might be able to devise novel strategies useful for engineering viral disease resistance.

  12. A Robust and Efficient Numerical Method for RNA-Mediated Viral Dynamics

    Directory of Open Access Journals (Sweden)

    Vladimir Reinharz

    2017-10-01

    Full Text Available The multiscale model of hepatitis C virus (HCV dynamics, which includes intracellular viral RNA (vRNA replication, has been formulated in recent years in order to provide a new conceptual framework for understanding the mechanism of action of a variety of agents for the treatment of HCV. We present a robust and efficient numerical method that belongs to the family of adaptive stepsize methods and is implicit, a Rosenbrock type method that is highly suited to solve this problem. We provide a Graphical User Interface that applies this method and is useful for simulating viral dynamics during treatment with anti-HCV agents that act against HCV on the molecular level.

  13. Viral RNA levels and env variants in semen and tissues of mature male rhesus macaques infected with SIV by penile inoculation.

    Directory of Open Access Journals (Sweden)

    Francis Fieni

    Full Text Available HIV is shed in semen but the anatomic site of virus entry into the genital secretions is unknown. We determined viral RNA (vRNA levels and the envelope gene sequence in the SIVmac 251 viral populations in the genital tract and semen of 5 adult male rhesus monkeys (Macaca mulatta that were infected after experimental penile SIV infection. Paired blood and semen samples were collected from 1-9 weeks after infection and the monkeys were necropsied eleven weeks after infection. The axillary lymph nodes, testes, epididymis, prostate, and seminal vesicles were collected and vRNA levels and single-genome analysis of the SIVmac251 env variants was performed. At the time of semen collection, blood vRNA levels were between 3.09 and 7.85 log10 vRNA copies/ml plasma. SIV RNA was found in the axillary lymph nodes of all five monkeys and in 3 of 5 monkeys, all tissues examined were vRNA positive. In these 3 monkeys, vRNA levels (log10 SIVgag copies/ug of total tissue RNA in the axillary lymph node (6.48 ± 0.50 were significantly higher than in the genital tract tissues: testis (3.67 ± 2.16; p<0.05, epididymis (3.08 ± 1.19; p<0.0001, prostate (3.36 ± 1.30; p<0.01, and seminal vesicle (2.67 ± 1.50; p<0.0001. Comparison of the SIVmac251 env viral populations in blood plasma, systemic lymph node, and genital tract tissues was performed in two of the macaques. Visual inspection of the Neighbor-Joining phylograms revealed that in both animals, all the sequences were generally distributed evenly among all tissue compartments. Importantly, viral populations in the genital tissues were not distinct from those in the systemic tissues. Our findings demonstrate striking similarity in the viral populations in the blood and male genital tract tissues within 3 months of penile SIV transmission.

  14. Spliceosome SNRNP200 Promotes Viral RNA Sensing and IRF3 Activation of Antiviral Response.

    Directory of Open Access Journals (Sweden)

    Nicolas Tremblay

    2016-07-01

    Full Text Available Spliceosomal SNRNP200 is a Ski2-like RNA helicase that is associated with retinitis pigmentosa 33 (RP33. Here we found that SNRNP200 promotes viral RNA sensing and IRF3 activation through the ability of its amino-terminal Sec63 domain (Sec63-1 to bind RNA and to interact with TBK1. We show that SNRNP200 relocalizes into TBK1-containing cytoplasmic structures upon infection, in contrast to the RP33-associated S1087L mutant, which is also unable to rescue antiviral response of SNRNP200 knockdown cells. This functional rescue correlates with the Sec63-1-mediated binding of viral RNA. The hindered IFN-β production of knockdown cells was further confirmed in peripheral blood cells of RP33 patients bearing missense mutation in SNRNP200 upon infection with Sendai virus (SeV. This work identifies a novel immunoregulatory role of the spliceosomal SNRNP200 helicase as an RNA sensor and TBK1 adaptor for the activation of IRF3-mediated antiviral innate response.

  15. Viral RNA Degradation and Diffusion Act as a Bottleneck for the Influenza A Virus Infection Efficiency.

    Directory of Open Access Journals (Sweden)

    Max Schelker

    2016-10-01

    Full Text Available After endocytic uptake, influenza viruses transit early endosomal compartments and eventually reach late endosomes. There, the viral glycoprotein hemagglutinin (HA triggers fusion between endosomal and viral membrane, a critical step that leads to release of the viral segmented genome destined to reach the cell nucleus. Endosomal maturation is a complex process involving acidification of the endosomal lumen as well as endosome motility along microtubules. While the pH drop is clearly critical for the conformational change and membrane fusion activity of HA, the effect of intracellular transport dynamics on the progress of infection remains largely unclear. In this study, we developed a comprehensive mathematical model accounting for the first steps of influenza virus infection. We calibrated our model with experimental data and challenged its predictions using recombinant viruses with altered pH sensitivity of HA. We identified the time point of virus-endosome fusion and thereby the diffusion distance of the released viral genome to the nucleus as a critical bottleneck for efficient virus infection. Further, we concluded and supported experimentally that the viral RNA is subjected to cytosolic degradation strongly limiting the probability of a successful genome import into the nucleus.

  16. Nuclear Export Signal Masking Regulates HIV-1 Rev Trafficking and Viral RNA Nuclear Export.

    Science.gov (United States)

    Behrens, Ryan T; Aligeti, Mounavya; Pocock, Ginger M; Higgins, Christina A; Sherer, Nathan M

    2017-02-01

    HIV-1's Rev protein forms a homo-oligomeric adaptor complex linking viral RNAs to the cellular CRM1/Ran-GTP nuclear export machinery through the activity of Rev's prototypical leucine-rich nuclear export signal (NES). In this study, we used a functional fluorescently tagged Rev fusion protein as a platform to study the effects of modulating Rev NES identity, number, position, or strength on Rev subcellular trafficking, viral RNA nuclear export, and infectious virion production. We found that Rev activity was remarkably tolerant of diverse NES sequences, including supraphysiological NES (SNES) peptides that otherwise arrest CRM1 transport complexes at nuclear pores. Rev's ability to tolerate a SNES was both position and multimerization dependent, an observation consistent with a model wherein Rev self-association acts to transiently mask the NES peptide(s), thereby biasing Rev's trafficking into the nucleus. Combined imaging and functional assays also indicated that NES masking underpins Rev's well-known tendency to accumulate at the nucleolus, as well as Rev's capacity to activate optimal levels of late viral gene expression. We propose that Rev multimerization and NES masking regulates Rev's trafficking to and retention within the nucleus even prior to RNA binding. HIV-1 infects more than 34 million people worldwide causing >1 million deaths per year. Infectious virion production is activated by the essential viral Rev protein that mediates nuclear export of intron-bearing late-stage viral mRNAs. Rev's shuttling into and out of the nucleus is regulated by the antagonistic activities of both a peptide-encoded N-terminal nuclear localization signal and C-terminal nuclear export signal (NES). How Rev and related viral proteins balance strong import and export activities in order to achieve optimal levels of viral gene expression is incompletely understood. We provide evidence that multimerization provides a mechanism by which Rev transiently masks its NES peptide

  17. Rift valley fever virus nonstructural protein NSs promotes viral RNA replication and transcription in a minigenome system.

    Science.gov (United States)

    Ikegami, Tetsuro; Peters, C J; Makino, Shinji

    2005-05-01

    Rift Valley fever virus (RVFV), which belongs to the genus Phlebovirus, family Bunyaviridae, has a tripartite negative-strand genome (S, M, and L segments) and is an important mosquito-borne pathogen for domestic animals and humans. We established an RVFV T7 RNA polymerase-driven minigenome system in which T7 RNA polymerase from an expression plasmid drove expression of RNA transcripts for viral proteins and minigenome RNA transcripts carrying a reporter gene between both termini of the M RNA segment in 293T cells. Like other viruses of the Bunyaviridae family, replication and transcription of the RVFV minigenome required expression of viral N and L proteins. Unexpectedly, the coexpression of an RVFV nonstructural protein, NSs, with N and L proteins resulted in a significant enhancement of minigenome RNA replication. Coexpression of NSs protein with N and L proteins also enhanced minigenome mRNA transcription in the cells expressing viral-sense minigenome RNA transcripts. NSs protein expression increased the RNA replication of minigenomes that originated from S and L RNA segments. Enhancement of minigenome RNA synthesis by NSs protein occurred in cells lacking alpha/beta interferon (IFN-alpha/beta) genes, indicating that the effect of NSs protein on minigenome RNA replication was unrelated to a putative NSs protein-induced inhibition of IFN-alpha/beta production. Our finding that RVFV NSs protein augmented minigenome RNA synthesis was in sharp contrast to reports that Bunyamwera virus (genus Bunyavirus) NSs protein inhibits viral minigenome RNA synthesis, suggesting that RVFV NSs protein and Bunyamwera virus NSs protein have distinctly different biological roles in viral RNA synthesis.

  18. Anti-Japanese-encephalitis-viral effects of kaempferol and daidzin and their RNA-binding characteristics.

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    Ting Zhang

    Full Text Available BACKGROUND: New therapeutic tools and molecular targets are needed for treatment of Japanese encephalitis virus (JEV infections. JEV requires an α-1 translational frameshift to synthesize the NS1' protein required for viral neuroinvasiveness. Several flavonoids have been shown to possess antiviral activity in vitro against a wide spectrum of viruses. To date, the antiviral activities of flavonol kaempferol (Kae and isoflavonoid daidzin (Dai against JEV have not been described. METHODOLOGY/PRINCIPAL FINDINGS: The 50% cytotoxic concentration (CC(50 and 50% effective concentration (EC(50 against JEV were investigated in BHK21 cells by MTS reduction. Activity against viral genomic RNA and proteins was measured by real-time RT-PCR and western blotting. The frameshift site RNA-binding characterization was also determined by electrospray ionization mass spectrometry, isothermal titration calorimetry and autodocking analysis. EC(50 values of Kae and Dai were 12.6 and 25.9 µM against JEV in cells pretreated before infection, whereas in cells infected before treatment, EC(50 was 21.5 and 40.4 µM, respectively. Kae exhibited more potent activity against JEV and RNA binding in cells following internalization through direct inhibition of viral replication and protein expression, indicating that its antiviral activity was principally due to direct virucidal effects. The JEV frameshift site RNA (fsRNA was selected as a target for assaying Kae and Dai. ITC of fsRNA revealed an apparent K(b value for Kae that was nine fold stronger than that for Dai. This binding was confirmed and localized to the RNA using ESI-MS and autodock analysis. Kae could form non-covalent complexes with fsRNA more easily than Dai could. CONCLUSIONS/SIGNIFICANCE: Kae demonstrates more potent antiviral activity against JEV than does Dai. The mode of action of Kae as an anti-JEV agent seems to be related to its ability to inactivate virus by binding with JEV fsRNA.

  19. Comparison of methods for miRNA extraction from plasma and quantitative recovery of RNA from plasma and cerebrospinal fluid

    Directory of Open Access Journals (Sweden)

    Melissa A McAlexander

    2013-05-01

    Full Text Available Interest in extracellular RNA has intensified as evidence accumulates that these molecules may be useful as indicators of a wide variety of biological conditions. To establish specific extracellular RNA molecules as clinically relevant biomarkers, reproducible recovery from biological samples and reliable measurements of the isolated RNA are paramount. Towards these ends, careful and rigorous comparisons of technical procedures are needed at all steps from sample handling to RNA isolation to RNA measurement protocols. In the investigations described in this methods paper, RT-qPCR was used to examine the apparent recovery of specific endogenous miRNAs and a spiked-in synthetic RNA from blood plasma samples. RNA was isolated using several widely used RNA isolation kits, with or without the addition of glycogen as a carrier. Kits examined included total RNA isolation systems that have been commercially available for several years and commonly adapted for extraction of biofluid RNA, as well as more recently introduced biofluids-specific RNA methods. Our conclusions include the following: some RNA isolation methods appear to be superior to others for the recovery of RNA from biological fluids; addition of a carrier molecule seems to be beneficial for some but not all isolation methods; and partially or fully quantitative recovery of RNA is observed from increasing volumes of plasma and cerebrospinal fluid.

  20. The proteasomal Rpn11 metalloprotease suppresses tombusvirus RNA recombination and promotes viral replication via facilitating assembly of the viral replicase complex.

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    Prasanth, K Reddisiva; Barajas, Daniel; Nagy, Peter D

    2015-03-01

    RNA viruses co-opt a large number of cellular proteins that affect virus replication and, in some cases, viral genetic recombination. RNA recombination helps viruses in an evolutionary arms race with the host's antiviral responses and adaptation of viruses to new hosts. Tombusviruses and a yeast model host are used to identify cellular factors affecting RNA virus replication and RNA recombination. In this study, we have examined the role of the conserved Rpn11p metalloprotease subunit of the proteasome, which couples deubiquitination and degradation of proteasome substrates, in tombusvirus replication and recombination in Saccharomyces cerevisiae and plants. Depletion or mutations of Rpn11p lead to the rapid formation of viral RNA recombinants in combination with reduced levels of viral RNA replication in yeast or in vitro based on cell extracts. Rpn11p interacts with the viral replication proteins and is recruited to the viral replicase complex (VRC). Analysis of the multifunctional Rpn11p has revealed that the primary role of Rpn11p is to act as a "matchmaker" that brings the viral p92(pol) replication protein and the DDX3-like Ded1p/RH20 DEAD box helicases into VRCs. Overexpression of Ded1p can complement the defect observed in rpn11 mutant yeast by reducing TBSV recombination. This suggests that Rpn11p can suppress tombusvirus recombination via facilitating the recruitment of the cellular Ded1p helicase, which is a strong suppressor of viral recombination, into VRCs. Overall, this work demonstrates that the co-opted Rpn11p, which is involved in the assembly of the functional proteasome, also functions in the proper assembly of the tombusvirus VRCs. RNA viruses evolve rapidly due to genetic changes based on mutations and RNA recombination. Viral genetic recombination helps viruses in an evolutionary arms race with the host's antiviral responses and facilitates adaptation of viruses to new hosts. Cellular factors affect viral RNA recombination, although the role

  1. Cellular La protein shields nonsegmented negative-strand RNA viral leader RNA from RIG-I and enhances virus growth by diverse mechanisms.

    Science.gov (United States)

    Bitko, Vira; Musiyenko, Alla; Bayfield, Mark A; Maraia, Richard J; Barik, Sailen

    2008-08-01

    The La antigen (SS-B) associates with a wide variety of cellular and viral RNAs to affect gene expression in multiple systems. We show that La is the major cellular protein found to be associated with the abundant 44-nucleotide viral leader RNA (leRNA) early after infection with respiratory syncytial virus (RSV), a nonsegmented negative-strand RNA virus. Consistent with this, La redistributes from the nucleus to the cytoplasm in RSV-infected cells. Upon RNA interference knockdown of La, leRNA is redirected to associate with the RNA-binding protein RIG-I, a known activator of interferon (IFN) gene expression, and this is accompanied by the early induction of IFN mRNA. These results suggest that La shields leRNA from RIG-I, abrogating the early viral activation of type I IFN. We mapped the leRNA binding function to RNA recognition motif 1 of La and showed that while wild-type La greatly enhanced RSV growth, a La mutant defective in RSV leRNA binding also did not support RSV growth. Comparative studies of RSV and Sendai virus and the use of IFN-negative Vero cells indicated that La supports the growth of nonsegmented negative-strand RNA viruses by both IFN suppression and a potentially novel IFN-independent mechanism.

  2. The double-stranded RNA-activated protein kinase mediates viral-induced encephalitis

    International Nuclear Information System (INIS)

    Scheuner, Donalyn; Gromeier, Matthias; Davies, Monique V.; Dorner, Andrew J.; Song Benbo; Patel, Rupali V.; Wimmer, Eckard J.; McLendon, Roger E.; Kaufman, Randal J.

    2003-01-01

    The double-stranded (ds) RNA-activated protein kinase (PKR) plays an important role in control of viral infections and cell growth. We have studied the role of PKR in viral infection in mice that are defective in the PKR signaling pathway. Transgenic mice were derived that constitutively express a trans-dominant-negative kinase-defective mutant PKR under control of the β-actin promoter. The trans-dominant-negative PKR mutant expressing transgenic mice do not have a detectable phenotype, similar to observations with PKR knock-out mice. The requirement for PKR in viral pathogenesis was studied by intracerebral infection of mice with a mouse-adapted poliovirus. Histopathological analysis revealed diffuse encephalomyelitis with severe inflammatory lesions throughout the central nervous system (CNS) in infected wild-type mice. In contrast, histopathological evaluation of virus-injected trans-dominant-negative PKR transgenic mice as well as PKR knock-out mice yielded no signs of tissue damage associated with inflammatory host responses. However, the virus did replicate in both models of PKR-deficient mice at a level equal to that observed in wild-type infected mice. Although the results indicate a clear difference in susceptibility to poliovirus-induced encephalitis, this difference manifests clinically as a slight delay in fatal neuropathy in trans-dominant-negative PKR transgenic and PKR knock-out animals. Our observations support the finding that viral-induced PKR activation may play a significant role in pathogenesis by mediating the host response to viral CNS infection. They support PKR to be an effective target to control tissue damage due to deleterious host responses to viral infection

  3. Viral replication. Structural basis for RNA replication by the hepatitis C virus polymerase.

    Science.gov (United States)

    Appleby, Todd C; Perry, Jason K; Murakami, Eisuke; Barauskas, Ona; Feng, Joy; Cho, Aesop; Fox, David; Wetmore, Diana R; McGrath, Mary E; Ray, Adrian S; Sofia, Michael J; Swaminathan, S; Edwards, Thomas E

    2015-02-13

    Nucleotide analog inhibitors have shown clinical success in the treatment of hepatitis C virus (HCV) infection, despite an incomplete mechanistic understanding of NS5B, the viral RNA-dependent RNA polymerase. Here we study the details of HCV RNA replication by determining crystal structures of stalled polymerase ternary complexes with enzymes, RNA templates, RNA primers, incoming nucleotides, and catalytic metal ions during both primed initiation and elongation of RNA synthesis. Our analysis revealed that highly conserved active-site residues in NS5B position the primer for in-line attack on the incoming nucleotide. A β loop and a C-terminal membrane-anchoring linker occlude the active-site cavity in the apo state, retract in the primed initiation assembly to enforce replication of the HCV genome from the 3' terminus, and vacate the active-site cavity during elongation. We investigated the incorporation of nucleotide analog inhibitors, including the clinically active metabolite formed by sofosbuvir, to elucidate key molecular interactions in the active site. Copyright © 2015, American Association for the Advancement of Science.

  4. Zinc Salts Block Hepatitis E Virus Replication by Inhibiting the Activity of Viral RNA-Dependent RNA Polymerase.

    Science.gov (United States)

    Kaushik, Nidhi; Subramani, Chandru; Anang, Saumya; Muthumohan, Rajagopalan; Shalimar; Nayak, Baibaswata; Ranjith-Kumar, C T; Surjit, Milan

    2017-11-01

    Hepatitis E virus (HEV) causes an acute, self-limiting hepatitis in healthy individuals and leads to chronic disease in immunocompromised individuals. HEV infection in pregnant women results in a more severe outcome, with the mortality rate going up to 30%. Though the virus usually causes sporadic infection, epidemics have been reported in developing and resource-starved countries. No specific antiviral exists against HEV. A combination of interferon and ribavirin therapy has been used to control the disease with some success. Zinc is an essential micronutrient that plays crucial roles in multiple cellular processes. Zinc salts are known to be effective in reducing infections caused by few viruses. Here, we investigated the effect of zinc salts on HEV replication. In a human hepatoma cell (Huh7) culture model, zinc salts inhibited the replication of genotype 1 (g-1) and g-3 HEV replicons and g-1 HEV infectious genomic RNA in a dose-dependent manner. Analysis of a replication-defective mutant of g-1 HEV genomic RNA under similar conditions ruled out the possibility of zinc salts acting on replication-independent processes. An ORF4-Huh7 cell line-based infection model of g-1 HEV further confirmed the above observations. Zinc salts did not show any effect on the entry of g-1 HEV into the host cell. Furthermore, our data reveal that zinc salts directly inhibit the activity of viral RNA-dependent RNA polymerase (RdRp), leading to inhibition of viral replication. Taken together, these studies unravel the ability of zinc salts in inhibiting HEV replication, suggesting their possible therapeutic value in controlling HEV infection. IMPORTANCE Hepatitis E virus (HEV) is a public health concern in resource-starved countries due to frequent outbreaks. It is also emerging as a health concern in developed countries owing to its ability to cause acute and chronic infection in organ transplant and immunocompromised individuals. Although antivirals such as ribavirin have been used

  5. Analysis of correlation between cerebrospinal fluid and plasma HIV-1 RNA levels in patients with neurological opportunistic diseases

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    Paulo Pereira Christo

    2011-08-01

    Full Text Available The question of whether HIV-1 RNA in cerebrospinal fluid (CSF is derived from viral replication in the central nervous system or simply reflects the transit of infected lymphocytes from the blood compartment has long been a matter of debate. Some studies found no correlation between CSF and plasma viral load, whereas others did. The lack of a correlation between the two compartments suggests that the presence of HIV-1 RNA is not simply due to the passive passage of the virus from blood to CSF but rather due to intrathecal replication. To evaluate the correlation between plasma and CSF HIV-1 RNA levels and to identify situations in which there is no correlation between the two compartments, seventy patients were prospectively studied. The association between CSF and plasma viral load was evaluated in the total population and in subgroups of patients with similar characteristics. A correlation between the CSF and plasma compartments was observed for patients undergoing highly active antiretroviral therapy (HAART, those with a CD4 T lymphocyte count lower than 200 cells/mm³, and those with increased CSF protein content. On the other hand, no correlation was observed for patients without adequate virological control, who had a CD4 count higher than 200 cells/mm³ and who did not use HAART. The correlation between the two compartments observed in some patients suggests that CSF HIV-1 RNA levels may reflect plasma levels in these subjects. In contrast, the lack of a correlation between the two compartments in patients who were not on HAART and who had normal CSF proteins and a poor virological control possibly indicates compartmentalization of the virus in CSF and, consequently, plasma-independent intrathecal viral replication.

  6. Comparison of tissue sample processing methods for harvesting the viral metagenome and a snapshot of the RNA viral community in a turkey gut.

    Science.gov (United States)

    Shah, Jigna D; Baller, Joshua; Zhang, Ying; Silverstein, Kevin; Xing, Zheng; Cardona, Carol J

    2014-12-01

    RNA viruses have been associated with enteritis in poultry and have been isolated from diseased birds. The same viral agents have also been detected in healthy flocks bringing into question their role in health and disease. In order to understand better eukaryotic viruses in the gut, this project focused on evaluating alternative methods to purify and concentrate viral particles, which do not involve the use of density gradients, for generating viral metagenome data. In this study, the sequence outcomes of three tissue processing methods have been evaluated and a data analysis pipeline has been established for RNA viruses from the gastrointestinal tract. In addition, with the use of the best method and increased sequencing depth, a glimpse of the RNA viral community in the gastrointestinal tract of a clinically normal 5-week old turkey is presented. The viruses from the Reoviridae and Astroviridae families together accounted for 76.3% of total viruses identified. The rarefaction curve at the species level further indicated that majority of the species diversity was included with the increased sequencing depth, implying that viruses from other viral families were present in very low abundance. Copyright © 2014 Elsevier B.V. All rights reserved.

  7. Small Interfering RNA Pathway Modulates Initial Viral Infection in Midgut Epithelium of Insect after Ingestion of Virus.

    Science.gov (United States)

    Lan, Hanhong; Chen, Hongyan; Liu, Yuyan; Jiang, Chaoyang; Mao, Qianzhuo; Jia, Dongsheng; Chen, Qian; Wei, Taiyun

    2016-01-15

    Numerous viruses are transmitted in a persistent manner by insect vectors. Persistent viruses establish their initial infection in the midgut epithelium, from where they disseminate to the midgut visceral muscles. Although propagation of viruses in insect vectors can be controlled by the small interfering RNA (siRNA) antiviral pathway, whether the siRNA pathway can control viral dissemination from the midgut epithelium is unknown. Infection by a rice virus (Southern rice black streaked dwarf virus [SRBSDV]) of its incompetent vector (the small brown planthopper [SBPH]) is restricted to the midgut epithelium. Here, we show that the siRNA pathway is triggered by SRBSDV infection in continuously cultured cells derived from the SBPH and in the midgut of the intact insect. Knockdown of the expression of the core component Dicer-2 of the siRNA pathway by RNA interference strongly increased the ability of SRBSDV to propagate in continuously cultured SBPH cells and in the midgut epithelium, allowing viral titers in the midgut epithelium to reach the threshold (1.99 × 10(9) copies of the SRBSDV P10 gene/μg of midgut RNA) needed for viral dissemination into the SBPH midgut muscles. Our results thus represent the first elucidation of the threshold for viral dissemination from the insect midgut epithelium. Silencing of Dicer-2 further facilitated the transmission of SRBSDV into rice plants by SBPHs. Taken together, our results reveal the new finding that the siRNA pathway can control the initial infection of the insect midgut epithelium by a virus, which finally affects the competence of the virus's vector. Many viral pathogens that cause significant global health and agricultural problems are transmitted via insect vectors. The first bottleneck in viral infection, the midgut epithelium, is a principal determinant of the ability of an insect species to transmit a virus. Southern rice black streaked dwarf virus (SRBSDV) is restricted exclusively to the midgut epithelium of an

  8. Cooler temperatures destabilize RNA interference and increase susceptibility of disease vector mosquitoes to viral infection.

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    Zach N Adelman

    Full Text Available The impact of global climate change on the transmission dynamics of infectious diseases is the subject of extensive debate. The transmission of mosquito-borne viral diseases is particularly complex, with climatic variables directly affecting many parameters associated with the prevalence of disease vectors. While evidence shows that warmer temperatures often decrease the extrinsic incubation period of an arthropod-borne virus (arbovirus, exposure to cooler temperatures often predisposes disease vector mosquitoes to higher infection rates. RNA interference (RNAi pathways are essential to antiviral immunity in the mosquito; however, few experiments have explored the effects of temperature on the RNAi machinery.We utilized transgenic "sensor" strains of Aedes aegypti to examine the role of temperature on RNA silencing. These "sensor" strains express EGFP only when RNAi is inhibited; for example, after knockdown of the effector proteins Dicer-2 (DCR-2 or Argonaute-2 (AGO-2. We observed an increase in EGFP expression in transgenic sensor mosquitoes reared at 18°C as compared with 28°C. Changes in expression were dependent on the presence of an inverted repeat with homology to a portion of the EGFP sequence, as transgenic strains lacking this sequence, the double stranded RNA (dsRNA trigger for RNAi, showed no change in EGFP expression when reared at 18°C. Sequencing small RNAs in sensor mosquitoes reared at low temperature revealed normal processing of dsRNA substrates, suggesting the observed deficiency in RNAi occurs downstream of DCR-2. Rearing at cooler temperatures also predisposed mosquitoes to higher levels of infection with both chikungunya and yellow fever viruses.This data suggest that microclimates, such as those present in mosquito breeding sites, as well as more general climactic variables may influence the dynamics of mosquito-borne viral diseases by affecting the antiviral immunity of disease vectors.

  9. Cytoplasmic viral RNA-dependent RNA polymerase disrupts the intracellular splicing machinery by entering the nucleus and interfering with Prp8.

    Directory of Open Access Journals (Sweden)

    Yen-Chin Liu

    2014-06-01

    Full Text Available The primary role of cytoplasmic viral RNA-dependent RNA polymerase (RdRp is viral genome replication in the cellular cytoplasm. However, picornaviral RdRp denoted 3D polymerase (3D(pol also enters the host nucleus, where its function remains unclear. In this study, we describe a novel mechanism of viral attack in which 3D(pol enters the nucleus through the nuclear localization signal (NLS and targets the pre-mRNA processing factor 8 (Prp8 to block pre-mRNA splicing and mRNA synthesis. The fingers domain of 3D(pol associates with the C-terminal region of Prp8, which contains the Jab1/MPN domain, and interferes in the second catalytic step, resulting in the accumulation of the lariat form of the splicing intermediate. Endogenous pre-mRNAs trapped by the Prp8-3D(pol complex in enterovirus-infected cells were identified and classed into groups associated with cell growth, proliferation, and differentiation. Our results suggest that picornaviral RdRp disrupts pre-mRNA splicing processes, that differs from viral protease shutting off cellular transcription and translation which contributes to the pathogenesis of viral infection.

  10. A 3'-end structure in RNA2 of a crinivirus is essential for viral RNA synthesis and contributes to replication-associated translation activity.

    Science.gov (United States)

    Mongkolsiriwattana, Chawin; Zhou, Jaclyn S; Ng, James C K

    2016-10-03

    The terminal ends in the genome of RNA viruses contain features that regulate viral replication and/or translation. We have identified a Y-shaped structure (YSS) in the 3' terminal regions of the bipartite genome of Lettuce chlorosis virus (LCV), a member in the genus Crinivirus (family Closteroviridae). The YSS is the first in this family of viruses to be determined using Selective 2'-Hydroxyl Acylation Analyzed by Primer Extension (SHAPE). Using luciferase constructs/replicons, in vivo and in vitro assays showed that the 5' and YSS-containing 3' terminal regions of LCV RNA1 supported translation activity. In contrast, similar regions from LCV RNA2, including those upstream of the YSS, did not. LCV RNA2 mutants with nucleotide deletions or replacements that affected the YSS were replication deficient. In addition, the YSS of LCV RNA1 and RNA2 were interchangeable without affecting viral RNA synthesis. Translation and significant replication were observed for specific LCV RNA2 replicons only in the presence of LCV RNA1, but both processes were impaired when the YSS and/or its upstream region were incomplete or altered. These results are evidence that the YSS is essential to the viral replication machinery, and contributes to replication enhancement and replication-associated translation activity in the RNA2 replicons.

  11. Viral Small-RNA Analysis of Bombyx mori Larval Midgut during Persistent and Pathogenic Cytoplasmic Polyhedrosis Virus Infection.

    Science.gov (United States)

    Zografidis, Aris; Van Nieuwerburgh, Filip; Kolliopoulou, Anna; Apostolou-Karampelis, Konstantinos; Head, Steven R; Deforce, Dieter; Smagghe, Guy; Swevers, Luc

    2015-11-01

    The lepidopteran innate immune response against RNA viruses remains poorly understood, while in other insects several studies have highlighted an essential role for the exo-RNAi pathway in combating viral infection. Here, by using deep-sequencing technology for viral small-RNA (vsRNA) assessment, we provide evidence that exo-RNAi is operative in the silkworm Bombyx mori against both persistent and pathogenic infection of B. mori cytoplasmic polyhedrosis virus (BmCPV) which is characterized by a segmented double-stranded RNA (dsRNA) genome. Further, we show that Dicer-2 predominantly targets viral dsRNA and produces 20-nucleotide (nt) vsRNAs, whereas an additional pathway is responsive to viral mRNA derived from segment 10. Importantly, vsRNA distributions, which define specific hot and cold spot profiles for each viral segment, to a considerable degree overlap between Dicer-2-related (19 to 21 nt) and Dicer-2-unrelated vsRNAs, suggesting a common origin for these profiles. We found a degenerate motif significantly enriched at the cut sites of vsRNAs of various lengths which link an unknown RNase to the origins of vsRNAs biogenesis and distribution. Accordingly, the indicated RNase activity may be an important early factor for the host's antiviral defense in Lepidoptera. This work contributes to the elucidation of the lepidopteran antiviral response against infection of segmented double-stranded RNA (dsRNA) virus (CPV; Reoviridae) and highlights the importance of viral small-RNA (vsRNA) analysis for getting insights into host-pathogen interactions. Three vsRNA pathways are implicated in antiviral defense. For dsRNA, two pathways are proposed, either based on Dicer-2 cleavage to generate 20-nucleotide vsRNAs or based on the activity of an uncharacterized endo-RNase that cleaves the viral RNA substrate at a degenerate motif. The analysis also indicates the existence of a degradation pathway that targets the positive strand of segment 10. Copyright © 2015, American

  12. Diagnosing acute HIV infection: The performance of quantitative HIV-1 RNA testing (viral load) in the 2014 laboratory testing algorithm.

    Science.gov (United States)

    Wu, Hsiu; Cohen, Stephanie E; Westheimer, Emily; Gay, Cynthia L; Hall, Laura; Rose, Charles; Hightow-Weidman, Lisa B; Gose, Severin; Fu, Jie; Peters, Philip J

    2017-08-01

    New recommendations for laboratory diagnosis of HIV infection in the United States were published in 2014. The updated testing algorithm includes a qualitative HIV-1 RNA assay to resolve discordant immunoassay results and to identify acute HIV-1 infection (AHI). The qualitative HIV-1 RNA assay is not widely available; therefore, we evaluated the performance of a more widely available quantitative HIV-1 RNA assay, viral load, for diagnosing AHI. We determined that quantitative viral loads consistently distinguished AHI from a false-positive immunoassay result. Among 100 study participants with AHI and a viral load result, the estimated geometric mean viral load was 1,377,793copies/mL. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. Editing of HIV-1 RNA by the double-stranded RNA deaminase ADAR1 stimulates viral infection

    Science.gov (United States)

    Doria, Margherita; Neri, Francesca; Gallo, Angela; Farace, Maria Giulia; Michienzi, Alessandro

    2009-01-01

    Adenosine deaminases that act on dsRNA (ADARs) are enzymes that target double-stranded regions of RNA converting adenosines into inosines (A-to-I editing) thus contributing to genome complexity and fine regulation of gene expression. It has been described that a member of the ADAR family, ADAR1, can target viruses and affect their replication process. Here we report evidence showing that ADAR1 stimulates human immuno deficiency virus type 1 (HIV-1) replication by using both editing-dependent and editing-independent mechanisms. We show that over-expression of ADAR1 in HIV-1 producer cells increases viral protein accumulation in an editing-independent manner. Moreover, HIV-1 virions generated in the presence of over-expressed ADAR1 but not an editing-inactive ADAR1 mutant are released more efficiently and display enhanced infectivity, as demonstrated by challenge assays performed with T cell lines and primary CD4+ T lymphocytes. Finally, we report that ADAR1 associates with HIV-1 RNAs and edits adenosines in the 5′ untranslated region (UTR) and the Rev and Tat coding sequence. Overall these results suggest that HIV-1 has evolved mechanisms to take advantage of specific RNA editing activity of the host cell and disclose a stimulatory function of ADAR1 in the spread of HIV-1. PMID:19651874

  14. Viral RNAi suppressor reversibly binds siRNA to outcompete Dicer and RISC via multiple-turnover

    Science.gov (United States)

    Rawlings, Renata A.; Krishnan, Vishalakshi; Walter, Nils G.

    2011-01-01

    RNA interference (RNAi) is a conserved gene regulatory mechanism employed by most eukaryotes as a key component of their innate immune response against viruses and retrotransposons. During viral infection, the RNase III-type endonuclease Dicer cleaves viral double-stranded RNA into small interfering RNAs (siRNAs), 21–24 nucleotides in length, and helps load them into the RNA-induced silencing complex (RISC) to guide cleavage of complementary viral RNA. As a countermeasure, many viruses have evolved viral RNA silencing suppressor (RSS) proteins that tightly, and presumably quantitatively, bind siRNAs to thwart RNAi-mediated degradation. Viral RSS proteins also act across kingdoms as potential immunosuppressors in gene therapeutic applications. Here we report fluorescence quenching and electrophoretic mobility shift assays that probe siRNA binding by the dimeric RSS p19 from Carnation Italian Ringspot Virus (CIRV), as well as by human Dicer and RISC assembly complexes. We find that the siRNA:p19 interaction is readily reversible, characterized by rapid binding ((1.69 ± 0.07)×108 M−1s−1) and marked dissociation (koff = 0.062 ± 0.002 s−1). We also observe that p19 efficiently competes with recombinant Dicer and inhibits formation of RISC-related assembly complexes found in human cell extract. Computational modeling based on these results provides evidence for the transient formation of a ternary complex between siRNA, human Dicer, and p19. An expanded model of RNA silencing indicates that multiple-turnover by reversible binding of siRNAs potentiates the efficiency of the suppressor protein. Our predictive model is expected to be applicable to the dosing of p19 as a silencing suppressor in viral gene therapy. PMID:21354178

  15. Differential expression of miRNA-423-5p in serum from cattle challenged with bovine viral diarrhea virus

    Science.gov (United States)

    Bovine viral diarrhea virus (BVDV) is an RNA virus that causes respiratory disease in cattle. MicroRNAs have been proposed as indicators of exposure to respiratory pathogens. However, microRNA profiles in cattle exposed to BVDV are currently nonexistent and few studies have been reported; therefore,...

  16. A Novel, Highly Selective Inhibitor of Pestivirus Replication That Targets the Viral RNA-Dependent RNA Polymerase

    Science.gov (United States)

    Paeshuyse, Jan; Leyssen, Pieter; Mabery, Eric; Boddeker, Nina; Vrancken, Robert; Froeyen, Matheus; Ansari, Israrul H.; Dutartre, Hélène; Rozenski, Jef; Gil, Laura H. V. G.; Letellier, Carine; Lanford, Robert; Canard, Bruno; Koenen, Frank; Kerkhofs, Pierre; Donis, Ruben O.; Herdewijn, Piet; Watson, Julia; De Clercq, Erik; Puerstinger, Gerhard; Neyts, Johan

    2006-01-01

    We report on the highly potent and selective antipestivirus activity of 5-[(4-bromophenyl)methyl]-2-phenyl-5H-imidazo[4,5-c]pyridine (BPIP). The 50% effective concentration (EC50) for inhibition of bovine viral diarrhea virus (BVDV)-induced cytopathic effect formation was 0.04 ± 0.01 μM. Comparable reduction of viral RNA synthesis (EC50 = 0.12 ± 0.02 μM) and production of infectious virus (EC50 = 0.074 ± 0.003 μM) were observed. The selectivity index (ratio of 50% cytostatic concentration/EC50) of BPIP was ∼2,000. BPIP was inactive against the hepatitis C virus subgenomic replicon and yellow fever virus but demonstrated weak activity against GB virus. Drug-resistant mutants were at least 300-fold less susceptible to BPIP than wild-type virus; showed cross-resistance to N-propyl-N-[2-(2H-1,2,4-triazino[5,6-b]indol-3-ylthio)ethyl]-1-propanamine (VP32947), and carried the F224S mutation in the viral RNA-dependent RNA polymerase (RdRp). When the F224S mutation was introduced into an infectious clone, the drug-resistant phenotype was obtained. BPIP did not inhibit the in vitro activity of recombinant BVDV RdRp, but did inhibit the activity of replication complexes (RCs). Computational docking revealed that F224 is located at the top of the finger domain of the polymerase. Docking of BPIP in the crystal structure of the BVDV RdRp revealed aromatic ring stacking, some hydrophobic contacts, and a hydrogen bond. Since two structurally unrelated compounds, i.e., BPIP and VP32947, target the same region of the BVDV RdRp, this position may be expected to be critical in the functioning of the polymerase or assembly of the RC. The potential of BPIP for the treatment of pestivirus and hepacivirus infections is discussed. PMID:16352539

  17. Persistence of ZIKV-RNA in the cellular fraction of semen is accompanied by a surrogate-marker of viral replication. Diagnostic implications for sexual transmission.

    Science.gov (United States)

    Biava, Mirella; Caglioti, Claudia; Castilletti, Concetta; Bordi, Licia; Carletti, Fabrizio; Colavita, Francesca; Quartu, Serena; Nicastri, Emanuele; Iannetta, Marco; Vairo, Francesco; Liuzzi, Giuseppina; Taglietti, Fabrizio; Ippolito, Giuseppe; Capobianchi, Maria Rosaria; Lalle, Eleonora

    2018-01-01

    As asymptomatic infections represent 80% of ZIKV-infected individuals, sexual transmission is a rising concern. Recent studies highlighted a preferential association of ZIKV with the cellular fraction (CF) of different specimen types. Our aim was to evaluate the presence of ZIKV-RNA in different body fluids, focusing on semen specimens to assess the ZIKV-RNA content in either the unfractionated sample, its CF or seminal plasma (SP). In addition, to establish if the presence of ZIKV genome was associated with active virus replication, we measured the levels of negative-strand ZIKV-RNA. ZIKV total-RNA was detected in blood, urine and unfractionated semen, and neg-RNA in semen CF and SP samples longitudinally collected from two ZIKV-positive men followed at the National Institute for Infectious Diseases "L. Spallanzani", Italy. In both patients, ZIKV total-RNA was detected in CF with ct values always lower than in the corresponding unfractionated samples, and was observed even in the CF from negative unfractionated semen samples. In Patient 2, neg-RNA was also detected in CF, suggesting ongoing viral replication. Our results demonstrate higher clinical sensitivity of CF as compared to whole semen testing, emphasizing the need to extend ZIKV-RNA testing to CF, to rule out virus presence and the possible risk of sexual transmission.

  18. Analyses of a whole-genome inter-clade recombination map of hepatitis delta virus suggest a host polymerase-driven and viral RNA structure-promoted template-switching mechanism for viral RNA recombination

    Science.gov (United States)

    Chao, Mei; Wang, Tzu-Chi; Lin, Chia-Chi; Yung-Liang Wang, Robert; Lin, Wen-Bin; Lee, Shang-En; Cheng, Ying-Yu; Yeh, Chau-Ting; Iang, Shan-Bei

    2017-01-01

    The genome of hepatitis delta virus (HDV) is a 1.7-kb single-stranded circular RNA that folds into an unbranched rod-like structure and has ribozyme activity. HDV redirects host RNA polymerase(s) (RNAP) to perform viral RNA-directed RNA transcription. RNA recombination is known to contribute to the genetic heterogeneity of HDV, but its molecular mechanism is poorly understood. Here, we established a whole-genome HDV-1/HDV-4 recombination map using two cloned sequences coexisting in cultured cells. Our functional analyses of the resulting chimeric delta antigens (the only viral-encoded protein) and recombinant genomes provide insights into how recombination promotes the genotypic and phenotypic diversity of HDV. Our examination of crossover distribution and subsequent mutagenesis analyses demonstrated that ribozyme activity on HDV genome, which is required for viral replication, also contributes to the generation of an inter-clade junction. These data provide circumstantial evidence supporting our contention that HDV RNA recombination occurs via a replication-dependent mechanism. Furthermore, we identify an intrinsic asymmetric bulge on the HDV genome, which appears to promote recombination events in the vicinity. We therefore propose a mammalian RNAP-driven and viral-RNA-structure-promoted template-switching mechanism for HDV genetic recombination. The present findings improve our understanding of the capacities of the host RNAP beyond typical DNA-directed transcription. PMID:28977829

  19. Identification of Proteins Bound to Dengue Viral RNA In Vivo Reveals New Host Proteins Important for Virus Replication

    Directory of Open Access Journals (Sweden)

    Stacia L. Phillips

    2016-01-01

    Full Text Available Dengue virus is the most prevalent cause of arthropod-borne infection worldwide. Due to the limited coding capacity of the viral genome and the complexity of the viral life cycle, host cell proteins play essential roles throughout the course of viral infection. Host RNA-binding proteins mediate various aspects of virus replication through their physical interactions with viral RNA. Here we describe a technique designed to identify such interactions in the context of infected cells using UV cross-linking followed by antisense-mediated affinity purification and mass spectrometry. Using this approach, we identified interactions, several of them novel, between host proteins and dengue viral RNA in infected Huh7 cells. Most of these interactions were subsequently validated using RNA immunoprecipitation. Using small interfering RNA (siRNA-mediated gene silencing, we showed that more than half of these host proteins are likely involved in regulating virus replication, demonstrating the utility of this method in identifying biologically relevant interactions that may not be identified using traditional in vitro approaches.

  20. MicroRNA-Mediated Gene Silencing in Plant Defense and Viral Counter-Defense

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    Sheng-Rui Liu

    2017-09-01

    Full Text Available MicroRNAs (miRNAs are non-coding RNAs of approximately 20–24 nucleotides in length that serve as central regulators of eukaryotic gene expression by targeting mRNAs for cleavage or translational repression. In plants, miRNAs are associated with numerous regulatory pathways in growth and development processes, and defensive responses in plant–pathogen interactions. Recently, significant progress has been made in understanding miRNA-mediated gene silencing and how viruses counter this defense mechanism. Here, we summarize the current knowledge and recent advances in understanding the roles of miRNAs involved in the plant defense against viruses and viral counter-defense. We also document the application of miRNAs in plant antiviral defense. This review discusses the current understanding of the mechanisms of miRNA-mediated gene silencing and provides insights on the never-ending arms race between plants and viruses.

  1. The stress granule component TIA-1 binds tick-borne encephalitis virus RNA and is recruited to perinuclear sites of viral replication to inhibit viral translation.

    Science.gov (United States)

    Albornoz, Amelina; Carletti, Tea; Corazza, Gianmarco; Marcello, Alessandro

    2014-06-01

    Flaviviruses are a major cause of disease in humans and animals worldwide. Tick-borne encephalitis virus (TBEV) is the most important arthropod-borne flavivirus endemic in Europe and is the etiological agent of tick-borne encephalitis, a potentially fatal infection of the central nervous system. However, the contributions of host proteins during TBEV infection are poorly understood. In this work, we investigate the cellular protein TIA-1 and its cognate factor TIAR, which are stress-induced RNA-binding proteins involved in the repression of initiation of translation of cellular mRNAs and in the formation of stress granules. We show that TIA-1 and TIAR interact with viral RNA in TBEV-infected cells. During TBEV infection, cytoplasmic TIA-1 and TIAR are recruited at sites of viral replication with concomitant depletion from stress granules. This effect is specific, since G3BP1, another component of these cytoplasmic structures, remains localized to stress granules. Moreover, heat shock induction of stress granules containing TIA-1, but not G3BP1, is inhibited in TBEV-infected cells. Infection of cells depleted of TIA-1 or TIAR by small interfering RNA (siRNA) or TIA-1(-/-) mouse fibroblasts, leads to a significant increase in TBEV extracellular infectivity. Interestingly, TIAR(-/-) fibroblasts show the opposite effect on TBEV infection, and this phenotype appears to be related to an excess of TIA-1 in these cells. Taking advantage of a TBE-luciferase replicon system, we also observed increased luciferase activity in TIA-1(-/-) mouse fibroblasts at early time points, consistent with TIA-1-mediated inhibition at the level of the first round of viral translation. These results indicate that, in response to TBEV infection, TIA-1 is recruited to sites of virus replication to bind TBEV RNA and modulate viral translation independently of stress granule (SG) formation. This study (i) extends previous work that showed TIA-1/TIAR recruitment at sites of flavivirus replication

  2. Structural organization of poliovirus RNA replication is mediated by viral proteins of the P2 genomic region

    International Nuclear Information System (INIS)

    Bienz, K.; Egger, D.; Troxler, M.; Pasamontes, L.

    1990-01-01

    Transcriptionally active replication complexes bound to smooth membrane vesicles were isolated from poliovirus-infected cells. In electron microscopic, negatively stained preparations, the replication complex appeared as an irregularly shaped, oblong structure attached to several virus-induced vesicles of a rosettelike arrangement. Electron microscopic immunocytochemistry of such preparations demonstrated that the poliovirus replication complex contains the proteins coded by the P2 genomic region (P2 proteins) in a membrane-associated form. In addition, the P2 proteins are also associated with viral RNA, and they can be cross-linked to viral RNA by UV irradiation. Guanidine hydrochloride prevented the P2 proteins from becoming membrane bound but did not change their association with viral RNA. The findings allow the conclusion that the protein 2C or 2C-containing precursor(s) is responsible for the attachment of the viral RNA to the vesicular membrane and for the spatial organization of the replication complex necessary for its proper functioning in viral transcription. A model for the structure of the viral replication complex and for the function of the 2C-containing P2 protein(s) and the vesicular membranes is proposed

  3. Bovine viral diarrhea virus: molecular cloning of genomic RNA and its diagnostic application

    International Nuclear Information System (INIS)

    Brock, K.V.

    1987-01-01

    Molecular cloning of a field isolate of bovine viral diarrhea virus (BVDV) strain 72 RNA was done in this study. The sensitivity and specificity of cloned cDNA sequences in hybridization assays with various BVDV strains were determined. cDNA was synthesized from polyadenylated BVDV RNA templates with oligo-dT primers, reverse transcriptase, and DNA polymerase I. The newly synthesized double-stranded BVDV cDNA was C-tailed with terminal deoxytransferase and annealed into G-tailed, Pst-1-cut pUC9 plasmid. Escherichia coli was transformed with the recombinant plasmids and a library of approximately 200 BVDV specific cDNA clones varying in length from 0.5 to 2.6 kilobases were isolated. The sensitivity and specificity of hybridization between the labelled cDNA and BVDV target sequences were determined. Cloned BVDV sequences were isolated from pUC9 plasmid DNA and labelled with 32 P by nick translation. The detection limit by dot blot hybridization assay was 20 pg of purified genomic BVDV RNA. cDNA hybridization probes were specific for all strains of BVDV tested, regardless of whether they were noncytopathic and cytopathic, but did not hybridize with heterologous bovine viruses tested. Probes did not hybridize with uninfected cell culture or cellular RNA. Hybridization probes were at least as sensitive as infectivity assays in detecting homologous virus

  4. Avian bornavirus in free-ranging waterfowl: prevalence of antibodies and cloacal shedding of viral RNA.

    Science.gov (United States)

    Delnatte, Pauline; Nagy, Éva; Ojkic, Davor; Leishman, David; Crawshaw, Graham; Elias, Kyle; Smith, Dale A

    2014-07-01

    We surveyed free-ranging Canada Geese (Branta canadensis), Trumpeter Swans (Cygnus buccinator), Mute Swans (Cygnus olor), and Mallards (Anas platyrhynchos) to estimate the prevalence of antibodies to avian bornavirus (ABV) and of cloacal shedding of ABV RNA in southern Ontario, Canada. Blood samples and cloacal swabs were collected from 206 free-ranging Canada Geese, 135 Trumpeter Swans, 75 Mute Swans, and 208 Mallards at 10 main capture sites between October 2010 and May 2012. Sera were assessed for antibodies against ABV by enzyme-linked immunosorbent assay and swabs were evaluated for ABV RNA using real-time reverse-transcription PCR. Serum antibodies were detected in birds from all four species and at each sampling site. Thirteen percent of the geese caught on the Toronto Zoo site shed ABV RNA in feces compared with 0% in geese sampled at three other locations. The proportions of shedders among Mute Swans, Trumpeter Swans, and Mallards were 9%, 0%, and 0%, respectively. Birds that were shedding viral RNA were more likely to have antibodies against ABV and to have higher antibody levels than those that were not, although many birds with antibodies were not shedding. We confirmed that exposure to, or infection with, ABV is widespread in asymptomatic free-ranging waterfowl in Canada; however, the correlation between cloacal shedding, presence of antibodies, and presence of disease is not fully understood.

  5. Comparison of viral RNA electrophoresis and indirect ELISA methods in the diagnosis of human rotavirus infection

    Energy Technology Data Exchange (ETDEWEB)

    Avendano, L F; Dubinovsky, S; James, Jr, H D

    1984-01-01

    A total of 177 stool samples from Chilean diarrhea patients under two years of age were tested for rotavirus by two methods - the indirect enzyme-linked immunosorbent assay (indirect ELISA) and viral RNA electrophoresis in agarose gels (v RNA EPH). Fifty of the specimens came from patients with acute diarrhea and 127 came from patients with protracted diarrhea. The indirect ELISA testing was performed at the National Institutes of Health in the United States: the electrophoretic testing was carried out in Santiago, Chile by the authors. The electrophoretic method detected rotavirus in 36% of the acute samples and 25% of the samples from protracted cases, while the indirect ELISA method detected rotavirus in higher percentages of samples - 46% and 38%, respectively. These results support the conclusion that v RNA EPH is a less sensitive method for detecting rotavirus than the indirect ELISA. Nevertheless, the former method's high specificity, ease of application, and low cost make it a worthwhile alternative to indirect ELISA. Thus, considering the important role played by rotavirus in infant diarrhea and the need for a diagnostic technique that can be incorporated into the routines of medical center laboratories in developing countries, there is good reason to conclude that v RNA EPH is a useful tool for studying rotavirus diarrhea. 18 refs, 3 tabs. Also published in the Bol. Oficina Sanit. Panam. (1984) v. 97(1), p. 1-7 (In Spanish).

  6. Comparison of viral RNA electrophoresis and indirect ELISA methods in the diagnosis of human rotavirus infection

    International Nuclear Information System (INIS)

    Avendano, L.F.; Dubinovsky, S.

    1984-01-01

    A total of 177 stool samples from Chilean diarrhea patients under two years of age were tested for rotavirus by two methods - the indirect enzyme-linked immunosorbent assay (indirect ELISA) and viral RNA electrophoresis in agarose gels (v RNA EPH). Fifty of the specimens came from patients with acute diarrhea and 127 came from patients with protracted diarrhea. The indirect ELISA testing was performed at the National Institutes of Health in the United States: the electrophoretic testing was carried out in Santiago, Chile by the authors. The electrophoretic method detected rotavirus in 36% of the acute samples and 25% of the samples from protracted cases, while the indirect ELISA method detected rotavirus in higher percentages of samples - 46% and 38%, respectively. These results support the conclusion that v RNA EPH is a less sensitive method for detecting rotavirus than the indirect ELISA. Nevertheless, the former method's high specificity, ease of application, and low cost make it a worthwhile alternative to indirect ELISA. Thus, considering the important role played by rotavirus in infant diarrhea and the need for a diagnostic technique that can be incorporated into the routines of medical center laboratories in developing countries, there is good reason to conclude that v RNA EPH is a useful tool for studying rotavirus diarrhea. (author)

  7. Water isotope effect on the thermostability of a polio viral RNA hairpin: A metadynamics study

    Science.gov (United States)

    Pathak, Arup K.; Bandyopadhyay, Tusar

    2017-04-01

    Oral polio vaccine is considered to be the most thermolabile of all the common childhood vaccines. Despite heavy water (D2O) having been known for a long time to stabilise attenuated viral RNA against thermodegradation, the molecular underpinnings of its mechanism of action are still lacking. Whereas, understanding the basis of D2O action is an important step that might reform the way other thermolabile drugs are stored and could possibly minimize the cold chain problem. Here using a combination of parallel tempering and well-tempered metadynamics simulation in light water (H2O) and in D2O, we have fully described the free energy surface associated with the folding/unfolding of a RNA hairpin containing a non-canonical basepair motif, which is conserved within the 3'-untranslated region of poliovirus-like enteroviruses. Simulations reveal that in heavy water (D2O) there is a considerable increase of the stability of the folded basin as monitored through an intramolecular hydrogen bond (HB), size, shape, and flexibility of RNA structures. This translates into a higher melting temperature in D2O by 41 K when compared with light water (H2O). We have explored the hydration dynamics of the RNA, hydration shell around the RNA surface, and spatial dependence of RNA-solvent collective HB dynamics in the two water systems. Simulation in heavy water clearly showed that D2O strengthens the HB network in the solvent, lengthens inter-residue water-bridge lifetime, and weakens dynamical coupling of the hairpin to its solvation environment, which enhances the rigidity of solvent exposed sites of the native configurations. The results might suggest that like other added osmoprotectants, D2O can act as a thermostabilizer when used as a solvent.

  8. Inhibition of post-transcriptional RNA processing by CDK inhibitors and its implication in anti-viral therapy.

    Directory of Open Access Journals (Sweden)

    Jitka Holcakova

    Full Text Available Cyclin-dependent kinases (CDKs are key regulators of the cell cycle and RNA polymerase II mediated transcription. Several pharmacological CDK inhibitors are currently in clinical trials as potential cancer therapeutics and some of them also exhibit antiviral effects. Olomoucine II and roscovitine, purine-based inhibitors of CDKs, were described as effective antiviral agents that inhibit replication of a broad range of wild type human viruses. Olomoucine II and roscovitine show high selectivity for CDK7 and CDK9, with important functions in the regulation of RNA polymerase II transcription. RNA polymerase II is necessary for viral transcription and following replication in cells. We analyzed the effect of inhibition of CDKs by olomoucine II on gene expression from viral promoters and compared its effect to widely-used roscovitine. We found that both roscovitine and olomoucine II blocked the phosphorylation of RNA polymerase II C-terminal domain. However the repression of genes regulated by viral promoters was strongly dependent on gene localization. Both roscovitine and olomoucine II inhibited expression only when the viral promoter was not integrated into chromosomal DNA. In contrast, treatment of cells with genome-integrated viral promoters increased their expression even though there was decreased phosphorylation of the C-terminal domain of RNA polymerase II. To define the mechanism responsible for decreased gene expression after pharmacological CDK inhibitor treatment, the level of mRNA transcription from extrachromosomal DNA was determined. Interestingly, our results showed that inhibition of RNA polymerase II C-terminal domain phosphorylation increased the number of transcribed mRNAs. However, some of these mRNAs were truncated and lacked polyadenylation, which resulted in decreased translation. These results suggest that phosphorylation of RNA polymerase II C-terminal domain is critical for linking transcription and posttrancriptional

  9. Which adherence measure - self-report, clinician recorded or pharmacy refill - is best able to predict detectable viral load in a public ART programme without routine plasma viral load monitoring?

    Science.gov (United States)

    Mekuria, Legese A; Prins, Jan M; Yalew, Alemayehu W; Sprangers, Mirjam A G; Nieuwkerk, Pythia T

    2016-07-01

    Combination antiretroviral therapy (cART) suppresses viral replication to an undetectable level if a sufficiently high level of adherence is achieved. We investigated which adherence measurement best distinguishes between patients with and without detectable viral load in a public ART programme without routine plasma viral load monitoring. We randomly selected 870 patients who started cART between May 2009 and April 2012 in 10 healthcare facilities in Addis Ababa, Ethiopia. Six hundred and sixty-four (76.3%) patients who were retained in HIV care and were receiving cART for at least 6 months were included and 642 had their plasma HIV-1 RNA concentration measured. Patients' adherence to cART was assessed according to self-report, clinician recorded and pharmacy refill measures. Multivariate logistic regression model was fitted to identify the predictors of detectable viremia. Model accuracy was evaluated by computing the area under the receiver operating characteristic (ROC) curve. A total of 9.2% and 5.5% of the 642 patients had a detectable viral load of ≥40 and ≥400 RNA copies/ml, respectively. In the multivariate analyses, younger age, lower CD4 cell count at cART initiation, being illiterate and widowed, and each of the adherence measures were significantly and independently predictive of having ≥400 RNA copies/ml. The ROC curve showed that these variables altogether had a likelihood of more than 80% to distinguish patients with a plasma viral load of ≥400 RNA copies/ml from those without. Adherence to cART was remarkably high. Self-report, clinician recorded and pharmacy refill non-adherence were all significantly predictive of detectable viremia. The choice for one of these methods to detect non-adherence and predict a detectable viral load can therefore be based on what is most practical in a particular setting. © 2016 John Wiley & Sons Ltd.

  10. First insight into the viral community of the cnidarian model metaorganism Aiptasia using RNA-Seq data

    KAUST Repository

    Brüwer, Jan D.

    2018-03-01

    Current research posits that all multicellular organisms live in symbioses with associated microorganisms and form so-called metaorganisms or holobionts. Cnidarian metaorganisms are of specific interest given that stony corals provide the foundation of the globally threatened coral reef ecosystems. To gain first insight into viruses associated with the coral model system Aiptasia (sensu Exaiptasia pallida), we analyzed an existing RNA-Seq dataset of aposymbiotic, partially populated, and fully symbiotic Aiptasia CC7 anemones with Symbiodinium. Our approach included the selective removal of anemone host and algal endosymbiont sequences and subsequent microbial sequence annotation. Of a total of 297 million raw sequence reads, 8.6 million (∼3%) remained after host and endosymbiont sequence removal. Of these, 3,293 sequences could be assigned as of viral origin. Taxonomic annotation of these sequences suggests that Aiptasia is associated with a diverse viral community, comprising 116 viral taxa covering 40 families. The viral assemblage was dominated by viruses from the families Herpesviridae (12.00%), Partitiviridae (9.93%), and Picornaviridae (9.87%). Despite an overall stable viral assemblage, we found that some viral taxa exhibited significant changes in their relative abundance when Aiptasia engaged in a symbiotic relationship with Symbiodinium. Elucidation of viral taxa consistently present across all conditions revealed a core virome of 15 viral taxa from 11 viral families, encompassing many viruses previously reported as members of coral viromes. Despite the non-random selection of viral genetic material due to the nature of the sequencing data analyzed, our study provides a first insight into the viral community associated with Aiptasia. Similarities of the Aiptasia viral community with those of corals corroborate the application of Aiptasia as a model system to study coral holobionts. Further, the change in abundance of certain viral taxa across different

  11. Using the Hepatitis C Virus RNA-Dependent RNA Polymerase as a Model to Understand Viral Polymerase Structure, Function and Dynamics

    Directory of Open Access Journals (Sweden)

    Ester Sesmero

    2015-07-01

    Full Text Available Viral polymerases replicate and transcribe the genomes of several viruses of global health concern such as Hepatitis C virus (HCV, human immunodeficiency virus (HIV and Ebola virus. For this reason they are key targets for therapies to treat viral infections. Although there is little sequence similarity across the different types of viral polymerases, all of them present a right-hand shape and certain structural motifs that are highly conserved. These features allow their functional properties to be compared, with the goal of broadly applying the knowledge acquired from studying specific viral polymerases to other viral polymerases about which less is known. Here we review the structural and functional properties of the HCV RNA-dependent RNA polymerase (NS5B in order to understand the fundamental processes underlying the replication of viral genomes. We discuss recent insights into the process by which RNA replication occurs in NS5B as well as the role that conformational changes play in this process.

  12. Influenza A Virus NS1 Protein Promotes Efficient Nuclear Export of Unspliced Viral M1 mRNA.

    Science.gov (United States)

    Pereira, Carina F; Read, Eliot K C; Wise, Helen M; Amorim, Maria J; Digard, Paul

    2017-08-01

    Influenza A virus mRNAs are transcribed by the viral RNA-dependent RNA polymerase in the cell nucleus before being exported to the cytoplasm for translation. Segment 7 produces two major transcripts: an unspliced mRNA that encodes the M1 matrix protein and a spliced transcript that encodes the M2 ion channel. Export of both mRNAs is dependent on the cellular NXF1/TAP pathway, but it is unclear how they are recruited to the export machinery or how the intron-containing but unspliced M1 mRNA bypasses the normal quality-control checkpoints. Using fluorescent in situ hybridization to monitor segment 7 mRNA localization, we found that cytoplasmic accumulation of unspliced M1 mRNA was inefficient in the absence of NS1, both in the context of segment 7 RNPs reconstituted by plasmid transfection and in mutant virus-infected cells. This effect was independent of any major effect on steady-state levels of segment 7 mRNA or splicing but corresponded to a ∼5-fold reduction in the accumulation of M1. A similar defect in intronless hemagglutinin (HA) mRNA nuclear export was seen with an NS1 mutant virus. Efficient export of M1 mRNA required both an intact NS1 RNA-binding domain and effector domain. Furthermore, while wild-type NS1 interacted with cellular NXF1 and also increased the interaction of segment 7 mRNA with NXF1, mutant NS1 polypeptides unable to promote mRNA export did neither. Thus, we propose that NS1 facilitates late viral gene expression by acting as an adaptor between viral mRNAs and the cellular nuclear export machinery to promote their nuclear export. IMPORTANCE Influenza A virus is a major pathogen of a wide variety of mammalian and avian species that threatens public health and food security. A fuller understanding of the virus life cycle is important to aid control strategies. The virus has a small genome that encodes relatively few proteins that are often multifunctional. Here, we characterize a new function for the NS1 protein, showing that, as well as

  13. Double-stranded RNA viral infection of Trichomonas vaginalis (TVV1) in Iranian isolates.

    Science.gov (United States)

    Khanaliha, Khadijeh; Masoumi-Asl, Hossein; Bokharaei-Salim, Farah; Tabatabaei, Azardokht; Naghdalipoor, Mehri

    2017-08-01

    The Totiviridae family includes a number of viruses that can infect protozoan parasites such as Leishmania and Giardia and fungi like Saccharomyces cerevisiae. Some isolates of Trichomonas vaginalis are also infected with one or more double-stranded RNA (dsRNA) viruses. In this study, the frequency of Trichomonas vaginalis virus (TVV1) was evaluated in Iranian isolates of T. vaginalis in Tehran, Iran. One thousand five hundred vaginal samples were collected from patients attending obstetrics and gynaecology hospitals associated with Iran University of Medical Sciences in Tehran, Iran from October 2015 to September 2016. Trichomonas vaginalis isolates were cultured in Diamond's modified medium. Nucleic acids were extracted using a DNA/RNA extraction kit and RT-PCR was performed. Among 1500 collected vaginal samples, 8 (0.53%) cases of T. vaginalis infection were found. Half (4/8) of the T. vaginalis positive cases were infected with TVV1. Phylogenetic mapping indicated that the Iranian isolates were most closely related to TVV1-OC5, TVV1-UR1. Iranian isolates of T. vaginalis were infected with TVV1. The frequency of viral infection (TVV1) in T. vaginalis isolates found in this study is higher than previously reported in Iran. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Comparison of protocols and RNA carriers for plasma miRNA isolation. Unraveling RNA carrier influence on miRNA isolation

    Science.gov (United States)

    Martos, Laura; Fernández-Pardo, Álvaro; Oto, Julia; Medina, Pilar; España, Francisco; Navarro, Silvia

    2017-01-01

    microRNAs are promising biomarkers in biological fluids in several diseases. Different plasma RNA isolation protocols and carriers are available, but their efficiencies have been scarcely compared. Plasma microRNAs were isolated using a phenol and column-based procedure and a column-based procedure, in the presence or absence of two RNA carriers (yeast RNA and MS2 RNA). We evaluated the presence of PCR inhibitors and the relative abundance of certain microRNAs by qRT-PCR. Furthermore, we analyzed the association between different isolation protocols, the relative abundance of the miRNAs in the sample, the GC content and the free energy of microRNAs. In all microRNAs analyzed, the addition of yeast RNA as a carrier in the different isolation protocols used gave lower raw Cq values, indicating higher microRNA recovery. Moreover, this increase in microRNAs recovery was dependent on their own relative abundance in the sample, their GC content and the free-energy of their own most stable secondary structure. Furthermore, the normalization of microRNA levels by an endogenous microRNA is more reliable than the normalization by plasma volume, as it reduced the difference in microRNA fold abundance between the different isolation protocols evaluated. Our thorough study indicates that a standardization of pre- and analytical conditions is necessary to obtain reproducible inter-laboratory results in plasma microRNA studies. PMID:29077772

  15. Variable RNA expression from recently acquired, endogenous viral elements (EVE) of white spot syndrome virus (WSSV) in shrimp.

    Science.gov (United States)

    Utari, Heny Budi; Soowannayan, Chumporn; Flegel, Timothy W; Whityachumnarnkul, Boonsirm; Kruatrachue, Maleeya

    2017-11-01

    The viral accommodation hypothesis proposes that endogenous viral elements (EVE) from both RNA and DNA viruses are being continually integrated into the shrimp genome by natural host processes and that they can result in tolerance to viral infection by fortuitous production of antisense, immunospecific RNA (imRNA). Thus, we hypothesized that previously reported microarray results for the presence of white spot syndrome virus (WSSV) open reading frames (ORFs) formerly called 151, 366 and 427 in a domesticated giant tiger shrimp (Penaeus monodon) breeding stock might have represented expression from EVE, since the stock had shown uninterrupted freedom from white spot disease (WSD) for many generations. To test this hypothesis, 128 specimens from a current stock generation were confirmed for freedom from WSSV infection using two nested PCR detection methods. Subsequent nested-PCR testing revealed 33/128 specimens (26%) positive for at least one of the ORF at very high sequence identity (95-99%) to extant WSSV. Positive results for ORF 366 (now known to be a fragment of the WSSV capsid protein gene) dominated (28/33 = 84.8%), so 9 arbitrarily selected 366-positive specimens were tested by strand-specific, nested RT-PCR using DNase-treated RNA templates. This revealed variable RNA expression in individual shrimp including no RNA transcripts (n = 1), sense transcripts only (n = 1), antisense transcripts only (n = 2) or transcripts of both sense (n = 5). The latter 7 expression products indicated specimens producing putative imRNA. The variable types and numbers of the EVE and the variable RNA expression (including potential imRNA) support predictions of the viral accommodation hypothesis that EVE are randomly produced and expressed. Positive nested PCR test results for EVE of ORF 366 using DNA templates derived from shrimp sperm (germ cells), indicated that they were heritable. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Wolbachia Blocks Viral Genome Replication Early in Infection without a Transcriptional Response by the Endosymbiont or Host Small RNA Pathways.

    Directory of Open Access Journals (Sweden)

    Stephanie M Rainey

    2016-04-01

    Full Text Available The intracellular endosymbiotic bacterium Wolbachia can protect insects against viral infection, and is being introduced into mosquito populations in the wild to block the transmission of arboviruses that infect humans and are a major public health concern. To investigate the mechanisms underlying this antiviral protection, we have developed a new model system combining Wolbachia-infected Drosophila melanogaster cell culture with the model mosquito-borne Semliki Forest virus (SFV; Togaviridae, Alphavirus. Wolbachia provides strong antiviral protection rapidly after infection, suggesting that an early stage post-infection is being blocked. Wolbachia does appear to have major effects on events distinct from entry, assembly or exit as it inhibits the replication of an SFV replicon transfected into the cells. Furthermore, it causes a far greater reduction in the expression of proteins from the 3' open reading frame than the 5' non-structural protein open reading frame, indicating that it is blocking the replication of viral RNA. Further to this separation of the replicase proteins and viral RNA in transreplication assays shows that uncoupling of viral RNA and replicase proteins does not overcome Wolbachia's antiviral activity. This further suggests that replicative processes are disrupted, such as translation or replication, by Wolbachia infection. This may occur by Wolbachia mounting an active antiviral response, but the virus did not cause any transcriptional response by the bacterium, suggesting that this is not the case. Host microRNAs (miRNAs have been implicated in protection, but again we found that host cell miRNA expression was unaffected by the bacterium and neither do our findings suggest any involvement of the antiviral siRNA pathway. We conclude that Wolbachia may directly interfere with early events in virus replication such as translation of incoming viral RNA or RNA transcription, and this likely involves an intrinsic (as opposed to

  17. An acutely and latently expressed herpes simplex virus 2 viral microRNA inhibits expression of ICP34.5, a viral neurovirulence factor.

    Science.gov (United States)

    Tang, Shuang; Bertke, Andrea S; Patel, Amita; Wang, Kening; Cohen, Jeffrey I; Krause, Philip R

    2008-08-05

    Latency-associated transcript (LAT) sequences regulate herpes simplex virus (HSV) latency and reactivation from sensory neurons. We found a HSV-2 LAT-related microRNA (miRNA) designated miR-I in transfected and infected cells in vitro and in acutely and latently infected ganglia of guinea pigs in vivo. miR-I is also expressed in human sacral dorsal root ganglia latently infected with HSV-2. miR-I is expressed under the LAT promoter in vivo in infected sensory ganglia. We also predicted and identified a HSV-1 LAT exon-2 viral miRNA in a location similar to miR-I, implying a conserved mechanism in these closely related viruses. In transfected and infected cells, miR-I reduces expression of ICP34.5, a key viral neurovirulence factor. We hypothesize that miR-I may modulate the outcome of viral infection in the peripheral nervous system by functioning as a molecular switch for ICP34.5 expression.

  18. HIV-1 Viral RNA Dynamics at the Plasma Membrane May Provide Insight into Viral Assembly | Poster

    Science.gov (United States)

    Many aspects of how infectious viruses assemble in cells have yet to be completely deciphered. However, as reported in a recent Journal of Virology paper, researchers may be one step closer to understanding how HIV-1, the virus that causes AIDS, assembles and replicates.

  19. Heterogeneous nuclear ribonuclear protein K interacts with Sindbis virus nonstructural proteins and viral subgenomic mRNA

    International Nuclear Information System (INIS)

    Burnham, Andrew J.; Gong, Lei; Hardy, Richard W.

    2007-01-01

    Alphaviruses are a group of arthropod-borne human and animal pathogens that can cause epidemics of significant public health and economic consequence. Alphavirus RNA synthesis requires four virally encoded nonstructural proteins and probably a number of cellular proteins. Using comparative two-dimensional electrophoresis we were able to identify proteins enriched in cytoplasmic membrane fractions containing viral RNA synthetic complexes following infection with Sindbis virus. Our studies demonstrated the following: (i) the host protein hnRNP K is enriched in cytoplasmic membrane fractions following Sindbis virus infection, (ii) viral nonstructural proteins co-immunoprecipitate with hnRNP K, (iii) nsP2 and hnRNP K co-localize in the cytoplasm of Sindbis virus infected cells, (iv) Sindbis virus subgenomic mRNA, but not genomic RNA co-immunoprecipitates with hnRNP K, (v) viral RNA does not appear to be required for the interaction of hnRNP K with the nonstructural proteins. Potential functions of hnRNP K during virus replication are discussed

  20. High-efficiency targeted editing of large viral genomes by RNA-guided nucleases.

    Science.gov (United States)

    Bi, Yanwei; Sun, Le; Gao, Dandan; Ding, Chen; Li, Zhihua; Li, Yadong; Cun, Wei; Li, Qihan

    2014-05-01

    A facile and efficient method for the precise editing of large viral genomes is required for the selection of attenuated vaccine strains and the construction of gene therapy vectors. The type II prokaryotic CRISPR-Cas (clustered regularly interspaced short palindromic repeats (CRISPR)-associated (Cas)) RNA-guided nuclease system can be introduced into host cells during viral replication. The CRISPR-Cas9 system robustly stimulates targeted double-stranded breaks in the genomes of DNA viruses, where the non-homologous end joining (NHEJ) and homology-directed repair (HDR) pathways can be exploited to introduce site-specific indels or insert heterologous genes with high frequency. Furthermore, CRISPR-Cas9 can specifically inhibit the replication of the original virus, thereby significantly increasing the abundance of the recombinant virus among progeny virus. As a result, purified recombinant virus can be obtained with only a single round of selection. In this study, we used recombinant adenovirus and type I herpes simplex virus as examples to demonstrate that the CRISPR-Cas9 system is a valuable tool for editing the genomes of large DNA viruses.

  1. High-efficiency targeted editing of large viral genomes by RNA-guided nucleases.

    Directory of Open Access Journals (Sweden)

    Yanwei Bi

    2014-05-01

    Full Text Available A facile and efficient method for the precise editing of large viral genomes is required for the selection of attenuated vaccine strains and the construction of gene therapy vectors. The type II prokaryotic CRISPR-Cas (clustered regularly interspaced short palindromic repeats (CRISPR-associated (Cas RNA-guided nuclease system can be introduced into host cells during viral replication. The CRISPR-Cas9 system robustly stimulates targeted double-stranded breaks in the genomes of DNA viruses, where the non-homologous end joining (NHEJ and homology-directed repair (HDR pathways can be exploited to introduce site-specific indels or insert heterologous genes with high frequency. Furthermore, CRISPR-Cas9 can specifically inhibit the replication of the original virus, thereby significantly increasing the abundance of the recombinant virus among progeny virus. As a result, purified recombinant virus can be obtained with only a single round of selection. In this study, we used recombinant adenovirus and type I herpes simplex virus as examples to demonstrate that the CRISPR-Cas9 system is a valuable tool for editing the genomes of large DNA viruses.

  2. Integration, viral charge and E2 mRNA levels in the progresion of intraepitelial cervical lesions

    Directory of Open Access Journals (Sweden)

    Esperanza Trujillo

    2018-01-01

    Full Text Available It is important to distinguish among squamous intraepithelial lesions (SIL those associated with increased risk cervical cancer. Our aim was to evaluate if the expression level of gen E2 in women with SIL and evidence of viral integration is associated to the grade of lesion. Cervical scrapes HPV16 positive from 19 women with normal histology, 45 women with low-grade SIL (LSIL and 45 women with high-grade SIL (HSIL were analyzed. Real-time PCR was used to quantify the mRNA of E2 and E2 and E6 genes to calculate viral load (E6 and the ratio E2/E6 to assess viral integration. Similar frequencies of E2 expression were found in LSIL and HSIL15/45 (33 %, the frequency in women without SIL was lower 3/19 (15.8 %, and all cases with E2 gene expression had mixed episomal and integrated viral DNA. The viral load increased significantly with the grade of SIL (p= 0.049, while E2/E6 ratio decreased (p=0.049. The ROC analysis showed low capacity of the three viral parameters analyzed to distinguish between low and high grade SIL. In conclusion although SIL with mixed and integrated viral DNA with E2 expression could be at lower risk of progression, and viral load and integration were associated with higher severity of the lesion, its clinical value as biomarkers of HSIL is limited.

  3. MicroRNA Expression during Viral Infection or PolyI:C Stimulation in a Fish Model

    DEFF Research Database (Denmark)

    Kristensen, Lasse Bøgelund Juel; Schyth, Brian Dall; Lorenzen, Niels

    Fish are important as small vertebrate models for studying various aspects of development and disease. MicroRNA regulation in fish has so far received attention especially in studies of their expression and function during embryonic development. In the studies carried out at the National Veterinary...... Institute in Århus we aim at using fish models for studying microRNA regulation during viral infection. In the studies presented here we make use of a qPCR method to detect miRNAs in fish cells. We present results regarding the expression of the immunologically relevant microRNAs, miR-155, miR-146a and mi......R-146b in fish cells during infection with the fish pathogenic virus viral hemorrhagic septicemia virus (VHSV) and during immune stimulation with double stranded RNA (polyI:C). We highlight the need of finding stable normalization genes for microRNA detection....

  4. Diverse activities of viral cis-acting RNA regulatory elements revealed using multicolor, long-term, single-cell imaging.

    Science.gov (United States)

    Pocock, Ginger M; Zimdars, Laraine L; Yuan, Ming; Eliceiri, Kevin W; Ahlquist, Paul; Sherer, Nathan M

    2017-02-01

    Cis-acting RNA structural elements govern crucial aspects of viral gene expression. How these structures and other posttranscriptional signals affect RNA trafficking and translation in the context of single cells is poorly understood. Herein we describe a multicolor, long-term (>24 h) imaging strategy for measuring integrated aspects of viral RNA regulatory control in individual cells. We apply this strategy to demonstrate differential mRNA trafficking behaviors governed by RNA elements derived from three retroviruses (HIV-1, murine leukemia virus, and Mason-Pfizer monkey virus), two hepadnaviruses (hepatitis B virus and woodchuck hepatitis virus), and an intron-retaining transcript encoded by the cellular NXF1 gene. Striking behaviors include "burst" RNA nuclear export dynamics regulated by HIV-1's Rev response element and the viral Rev protein; transient aggregations of RNAs into discrete foci at or near the nuclear membrane triggered by multiple elements; and a novel, pulsiform RNA export activity regulated by the hepadnaviral posttranscriptional regulatory element. We incorporate single-cell tracking and a data-mining algorithm into our approach to obtain RNA element-specific, high-resolution gene expression signatures. Together these imaging assays constitute a tractable, systems-based platform for studying otherwise difficult to access spatiotemporal features of viral and cellular gene regulation. © 2017 Pocock et al. This article is distributed by The American Society for Cell Biology under license from the author(s). Two months after publication it is available to the public under an Attribution–Noncommercial–Share Alike 3.0 Unported Creative Commons License (http://creativecommons.org/licenses/by-nc-sa/3.0).

  5. Inactivation of the host lipin gene accelerates RNA virus replication through viral exploitation of the expanded endoplasmic reticulum membrane.

    Directory of Open Access Journals (Sweden)

    Chingkai Chuang

    2014-02-01

    Full Text Available RNA viruses take advantage of cellular resources, such as membranes and lipids, to assemble viral replicase complexes (VRCs that drive viral replication. The host lipins (phosphatidate phosphatases are particularly interesting because these proteins play key roles in cellular decisions about membrane biogenesis versus lipid storage. Therefore, we examined the relationship between host lipins and tombusviruses, based on yeast model host. We show that deletion of PAH1 (phosphatidic acid phosphohydrolase, which is the single yeast homolog of the lipin gene family of phosphatidate phosphatases, whose inactivation is responsible for proliferation and expansion of the endoplasmic reticulum (ER membrane, facilitates robust RNA virus replication in yeast. We document increased tombusvirus replicase activity in pah1Δ yeast due to the efficient assembly of VRCs. We show that the ER membranes generated in pah1Δ yeast is efficiently subverted by this RNA virus, thus emphasizing the connection between host lipins and RNA viruses. Thus, instead of utilizing the peroxisomal membranes as observed in wt yeast and plants, TBSV readily switches to the vastly expanded ER membranes in lipin-deficient cells to build VRCs and support increased level of viral replication. Over-expression of the Arabidopsis Pah2p in Nicotiana benthamiana decreased tombusvirus accumulation, validating that our findings are also relevant in a plant host. Over-expression of AtPah2p also inhibited the ER-based replication of another plant RNA virus, suggesting that the role of lipins in RNA virus replication might include several more eukaryotic viruses.

  6. Analysis of IAV Replication and Co-infection Dynamics by a Versatile RNA Viral Genome Labeling Method

    Directory of Open Access Journals (Sweden)

    Dan Dou

    2017-07-01

    Full Text Available Genome delivery to the proper cellular compartment for transcription and replication is a primary goal of viruses. However, methods for analyzing viral genome localization and differentiating genomes with high identity are lacking, making it difficult to investigate entry-related processes and co-examine heterogeneous RNA viral populations. Here, we present an RNA labeling approach for single-cell analysis of RNA viral replication and co-infection dynamics in situ, which uses the versatility of padlock probes. We applied this method to identify influenza A virus (IAV infections in cells and lung tissue with single-nucleotide specificity and to classify entry and replication stages by gene segment localization. Extending the classification strategy to co-infections of IAVs with single-nucleotide variations, we found that the dependence on intracellular trafficking places a time restriction on secondary co-infections necessary for genome reassortment. Altogether, these data demonstrate how RNA viral genome labeling can help dissect entry and co-infections.

  7. Role of alfalfa mosaic virus coat protein in regulation of the balance between viral plus and minus strand RNA synthesis

    NARCIS (Netherlands)

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

    1991-01-01

    Replication of wild type RNA 3 of alfalfa mosaic virus (AIMV) and mutants with frameshifts in the P3 or coat protein (CP) genes was studied in protoplasts from tobacco plants transformed with DNA copies of AIMV RNAs 1 and 2. Accumulation of viral plus and minus strand RNAs was monitored with

  8. Assay reproducibility in clinical studies of plasma miRNA.

    Directory of Open Access Journals (Sweden)

    Jonathan Rice

    Full Text Available There are increasing reports of plasma miRNAs as biomarkers of human disease but few standards in methodologic reporting, leading to inconsistent data. We systematically reviewed plasma miRNA studies published between July 2013-June 2014 to assess methodology. Six parameters were investigated: time to plasma extraction, methods of RNA extraction, type of miRNA, quantification, cycle threshold (Ct setting, and methods of statistical analysis. We compared these data with a proposed standard methodologic technique. Beginning with initial screening for 380 miRNAs using microfluidic array technology and validation in an additional cohort of patients, we compared 11 miRNAs that exhibited differential expression between 16 patients with benign colorectal neoplasms (advanced adenomas and 16 patients without any neoplasm (controls. Plasma was isolated immediately, 12, 24, 48, or 72 h following phlebotomy. miRNA was extracted using two different techniques (Trizol LS with pre-amplification or modified miRNeasy. We performed Taqman-based RT-PCR assays for the 11 miRNAs with subsequent analyses using a variable Ct setting or a fixed Ct set at 0.01, 0.03, 0.05, or 0.5. Assays were performed in duplicate by two different operators. RNU6 was the internal reference. Systematic review yielded 74 manuscripts meeting inclusion criteria. One manuscript (1.4% documented all 6 methodological parameters, while < 5% of studies listed Ct setting. In our proposed standard technique, plasma extraction ≤12 h provided consistent ΔCt. miRNeasy extraction yielded higher miRNA concentrations and fewer non-expressed miRNAs compared to Trizol LS (1/704 miRNAs [0.14%] vs 109/704 miRNAs [15%], not expressed, respectively. A fixed Ct bar setting of 0.03 yielded the most reproducible data, provided that <10% miRNA were non-expressed. There was no significant intra-operator variability. There was significant inter-operator variation using Trizol LS extraction, while this was

  9. Targeting membrane-bound viral RNA synthesis reveals potent inhibition of diverse coronaviruses including the middle East respiratory syndrome virus.

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    Anna Lundin

    2014-05-01

    Full Text Available Coronaviruses raise serious concerns as emerging zoonotic viruses without specific antiviral drugs available. Here we screened a collection of 16671 diverse compounds for anti-human coronavirus 229E activity and identified an inhibitor, designated K22, that specifically targets membrane-bound coronaviral RNA synthesis. K22 exerts most potent antiviral activity after virus entry during an early step of the viral life cycle. Specifically, the formation of double membrane vesicles (DMVs, a hallmark of coronavirus replication, was greatly impaired upon K22 treatment accompanied by near-complete inhibition of viral RNA synthesis. K22-resistant viruses contained substitutions in non-structural protein 6 (nsp6, a membrane-spanning integral component of the viral replication complex implicated in DMV formation, corroborating that K22 targets membrane bound viral RNA synthesis. Besides K22 resistance, the nsp6 mutants induced a reduced number of DMVs, displayed decreased specific infectivity, while RNA synthesis was not affected. Importantly, K22 inhibits a broad range of coronaviruses, including Middle East respiratory syndrome coronavirus (MERS-CoV, and efficient inhibition was achieved in primary human epithelia cultures representing the entry port of human coronavirus infection. Collectively, this study proposes an evolutionary conserved step in the life cycle of positive-stranded RNA viruses, the recruitment of cellular membranes for viral replication, as vulnerable and, most importantly, druggable target for antiviral intervention. We expect this mode of action to serve as a paradigm for the development of potent antiviral drugs to combat many animal and human virus infections.

  10. Diagnostic Test Accuracy of a 2-Transcript Host RNA Signature for Discriminating Bacterial vs Viral Infection in Febrile Children.

    Science.gov (United States)

    Herberg, Jethro A; Kaforou, Myrsini; Wright, Victoria J; Shailes, Hannah; Eleftherohorinou, Hariklia; Hoggart, Clive J; Cebey-López, Miriam; Carter, Michael J; Janes, Victoria A; Gormley, Stuart; Shimizu, Chisato; Tremoulet, Adriana H; Barendregt, Anouk M; Salas, Antonio; Kanegaye, John; Pollard, Andrew J; Faust, Saul N; Patel, Sanjay; Kuijpers, Taco; Martinón-Torres, Federico; Burns, Jane C; Coin, Lachlan J M; Levin, Michael

    Because clinical features do not reliably distinguish bacterial from viral infection, many children worldwide receive unnecessary antibiotic treatment, while bacterial infection is missed in others. To identify a blood RNA expression signature that distinguishes bacterial from viral infection in febrile children. Febrile children presenting to participating hospitals in the United Kingdom, Spain, the Netherlands, and the United States between 2009-2013 were prospectively recruited, comprising a discovery group and validation group. Each group was classified after microbiological investigation as having definite bacterial infection, definite viral infection, or indeterminate infection. RNA expression signatures distinguishing definite bacterial from viral infection were identified in the discovery group and diagnostic performance assessed in the validation group. Additional validation was undertaken in separate studies of children with meningococcal disease (n = 24) and inflammatory diseases (n = 48) and on published gene expression datasets. A 2-transcript RNA expression signature distinguishing bacterial infection from viral infection was evaluated against clinical and microbiological diagnosis. Definite bacterial and viral infection was confirmed by culture or molecular detection of the pathogens. Performance of the RNA signature was evaluated in the definite bacterial and viral group and in the indeterminate infection group. The discovery group of 240 children (median age, 19 months; 62% male) included 52 with definite bacterial infection, of whom 36 (69%) required intensive care, and 92 with definite viral infection, of whom 32 (35%) required intensive care. Ninety-six children had indeterminate infection. Analysis of RNA expression data identified a 38-transcript signature distinguishing bacterial from viral infection. A smaller (2-transcript) signature (FAM89A and IFI44L) was identified by removing highly correlated transcripts. When this 2-transcript

  11. Acute hepatitis A virus infection is associated with a limited type I interferon response and persistence of intrahepatic viral RNA.

    Science.gov (United States)

    Lanford, Robert E; Feng, Zongdi; Chavez, Deborah; Guerra, Bernadette; Brasky, Kathleen M; Zhou, Yan; Yamane, Daisuke; Perelson, Alan S; Walker, Christopher M; Lemon, Stanley M

    2011-07-05

    Hepatitis A virus (HAV) is an hepatotropic human picornavirus that is associated only with acute infection. Its pathogenesis is not well understood because there are few studies in animal models using modern methodologies. We characterized HAV infections in three chimpanzees, quantifying viral RNA by quantitative RT-PCR and examining critical aspects of the innate immune response including intrahepatic IFN-stimulated gene expression. We compared these infection profiles with similar studies of chimpanzees infected with hepatitis C virus (HCV), an hepatotropic flavivirus that frequently causes persistent infection. Surprisingly, HAV-infected animals exhibited very limited induction of type I IFN-stimulated genes in the liver compared with chimpanzees with acute resolving HCV infection, despite similar levels of viremia and 100-fold greater quantities of viral RNA in the liver. Minimal IFN-stimulated gene 15 and IFIT1 responses peaked 1-2 wk after HAV challenge and then subsided despite continuing high hepatic viral RNA. An acute inflammatory response at 3-4 wk correlated with the appearance of virus-specific antibodies and apoptosis and proliferation of hepatocytes. Despite this, HAV RNA persisted in the liver for months, remaining present long after clearance from serum and feces and revealing dramatic differences in the kinetics of clearance in the three compartments. Viral RNA was detected in the liver for significantly longer (35 to >48 wk) than HCV RNA in animals with acute resolving HCV infection (10-20 wk). Collectively, these findings indicate that HAV is far stealthier than HCV early in the course of acute resolving infection. HAV infections represent a distinctly different paradigm in virus-host interactions within the liver.

  12. Functional interactions of nucleocapsid protein of feline immunodeficiency virus and cellular prion protein with the viral RNA.

    Science.gov (United States)

    Moscardini, Mila; Pistello, Mauro; Bendinelli, M; Ficheux, Damien; Miller, Jennifer T; Gabus, Caroline; Le Grice, Stuart F J; Surewicz, Witold K; Darlix, Jean-Luc

    2002-04-19

    All lentiviruses and oncoretroviruses examined so far encode a major nucleic-acid binding protein (nucleocapsid or NC* protein), approximately 2500 molecules of which coat the dimeric RNA genome. Studies on HIV-1 and MoMuLV using in vitro model systems and in vivo have shown that NC protein is required to chaperone viral RNA dimerization and packaging during virus assembly, and proviral DNA synthesis by reverse transcriptase (RT) during infection. The human cellular prion protein (PrP), thought to be the major component of the agent causing transmissible spongiform encephalopathies (TSE), was recently found to possess a strong affinity for nucleic acids and to exhibit chaperone properties very similar to HIV-1 NC protein in the HIV-1 context in vitro. Tight binding of PrP to nucleic acids is proposed to participate directly in the prion disease process. To extend our understanding of lentiviruses and of the unexpected nucleic acid chaperone properties of the human prion protein, we set up an in vitro system to investigate replication of the feline immunodeficiency virus (FIV), which is functionally and phylogenetically distant from HIV-1. The results show that in the FIV model system, NC protein chaperones viral RNA dimerization, primer tRNA(Lys,3) annealing to the genomic primer-binding site (PBS) and minus strand DNA synthesis by the homologous FIV RT. FIV NC protein is able to trigger specific viral DNA synthesis by inhibiting self-priming of reverse transcription. The human prion protein was found to mimic the properties of FIV NC with respect to primer tRNA annealing to the viral RNA and chaperoning minus strand DNA synthesis. Copyright 2002 Elsevier Science Ltd.

  13. Genomic segments RNA1 and RNA2 of Prunus necrotic ringspot virus codetermine viral pathogenicity to adapt to alternating natural Prunus hosts.

    Science.gov (United States)

    Cui, Hongguang; Hong, Ni; Wang, Guoping; Wang, Aiming

    2013-05-01

    Prunus necrotic ringspot virus (PNRSV) affects Prunus fruit production worldwide. To date, numerous PNRSV isolates with diverse pathological properties have been documented. To study the pathogenicity of PNRSV, which directly or indirectly determines the economic losses of infected fruit trees, we have recently sequenced the complete genome of peach isolate Pch12 and cherry isolate Chr3, belonging to the pathogenically aggressive PV32 group and mild PV96 group, respectively. Here, we constructed the Chr3- and Pch12-derived full-length cDNA clones that were infectious in the experimental host cucumber and their respective natural Prunus hosts. Pch12-derived clones induced much more severe symptoms than Chr3 in cucumber, and the pathogenicity discrepancy between Chr3 and Pch12 was associated with virus accumulation. By reassortment of genomic segments, swapping of partial genomic segments, and site-directed mutagenesis, we identified the 3' terminal nucleotide sequence (1C region) in RNA1 and amino acid K at residue 279 in RNA2-encoded P2 as the severe virulence determinants in Pch12. Gain-of-function experiments demonstrated that both the 1C region and K279 of Pch12 were required for severe virulence and high levels of viral accumulation. Our results suggest that PNRSV RNA1 and RNA2 codetermine viral pathogenicity to adapt to alternating natural Prunus hosts, likely through mediating viral accumulation.

  14. Disruption of Claudin-1 Expression by miRNA-182 Alters the Susceptibility to Viral Infectivity in HCV Cell Models

    Directory of Open Access Journals (Sweden)

    Sarah E. Riad

    2018-03-01

    Full Text Available HCV entry involves a complex interplay between viral and host molecules. During post-binding interactions, the viral E2 complexes with CD81 receptor for delivery to the tight junction proteins CLDN1 and OCLN, which aid in viral internalization. Targeting HCV entry receptors represents an appealing approach to inhibit viral infectivity. This study aimed at investigating the impact of targeting CLDN1 by microRNAs on HCV infectivity. miR-155 was previously shown to target the 3′UTR of CLDN1 mRNA. Therefore, miR-155 was used as a control in this study. In-silico analysis and luciferase reporter assay were utilized to identify potential targeting miRNAs. The impact of the identified miRNAs on CLDN1 mRNA and protein expression was examined by qRT-PCR, indirect immunofluorescence and western blotting, respectively. The role of the selected miRNAs on HCV infectivity was assessed by measuring the viral load following the ectopic expression of the selected miRNAs. miR-182 was identified in-silico and by experimental validation to target CLDN1. Both miR-155 and miR-182 inhibited CLDN1 mRNA and protein expression in infected Huh7 cells. Ectopic expression of miR-155 increased, while miR-182 reduced the viral load. In conclusion, despite repressing CLDN1, the impact of miR-155 and miR-182 on HCV infectivity is contradictory. Ectopic miR-182 expression is suggested as an upstream regulator of the entry factor CLDN1, harnessing HCV infection.

  15. Viral RNA testing and automation on the bead-based CBNE detection microsystem.

    Energy Technology Data Exchange (ETDEWEB)

    Galambos, Paul C.; Bourdon, Christopher Jay; Farrell, Cara M.; Rossito, Paul (University of California at Davis); McClain, Jaime L.; Derzon, Mark Steven; Cullor, James Sterling (University of California at Davis); Rahimian, Kamayar

    2008-09-01

    We developed prototype chemistry for nucleic acid hybridization on our bead-based diagnostics platform and we established an automatable bead handling protocol capable of 50 part-per-billion (ppb) sensitivity. We are working towards a platform capable of parallel, rapid (10 minute), raw sample testing for orthogonal (in this case nucleic acid and immunoassays) identification of biological (and other) threats in a single sensor microsystem. In this LDRD we developed the nucleic acid chemistry required for nucleic acid hybridization. Our goal is to place a non-cell associated RNA virus (Bovine Viral Diarrhea, BVD) on the beads for raw sample testing. This key pre-requisite to showing orthogonality (nucleic acid measurements can be performed in parallel with immunoassay measurements). Orthogonal detection dramatically reduces false positives. We chose BVD because our collaborators (UC-Davis) can supply samples from persistently infected animals; and because proof-of-concept field testing can be performed with modification of the current technology platform at the UC Davis research station. Since BVD is a cattle-prone disease this research dovetails with earlier immunoassay work on Botulinum toxin simulant testing in raw milk samples. Demonstration of BVD RNA detection expands the repertoire of biological macromolecules that can be adapted to our bead-based detection. The resources of this late start LDRD were adequate to partially demonstrate the conjugation of the beads to the nucleic acids. It was never expected to be adequate for a full live virus test but to motivate that additional investment. In addition, we were able to reduce the LOD (Limit of Detection) for the botulinum toxin stimulant to 50 ppb from the earlier LOD of 1 ppm. A low LOD combined with orthogonal detection provides both low false negatives and low false positives. The logical follow-on steps to this LDRD research are to perform live virus identification as well as concurrent nucleic acid and

  16. The Mechanism of Synchronous Precise Regulation of Two Shrimp White Spot Syndrome Virus Targets by a Viral MicroRNA

    Science.gov (United States)

    He, Yaodong; Ma, Tiantian; Zhang, Xiaobo

    2017-01-01

    MicroRNAs (miRNAs), important factors in animal innate immunity, suppress the expressions of their target genes by binding to target mRNA’s 3′ untranslated regions (3′UTRs). However, the mechanism of synchronous regulation of multiple targets by a single miRNA remains unclear. In this study, the interaction between a white spot syndrome virus (WSSV) miRNA (WSSV-miR-N32) and its two viral targets (wsv459 and wsv322) was characterized in WSSV-infected shrimp. The outcomes indicated that WSSV-encoded miRNA (WSSV-miR-N32) significantly inhibited virus infection by simultaneously targeting wsv459 and wsv322. The silencing of wsv459 or wsv322 by siRNA led to significant decrease of WSSV copies in shrimp, showing that the two viral genes were required for WSSV infection. WSSV-miR-N32 could mediate 5′–3′ exonucleolytic digestion of its target mRNAs, which stopped at the sites of target mRNA 3′UTRs close to the sequence complementary to the miRNA seed sequence. The complementary bases (to the target mRNA sequence) of a miRNA 9th–18th non-seed sequence were essential for the miRNA targeting. Therefore, our findings presented novel insights into the mechanism of miRNA-mediated suppression of target gene expressions, which would be helpful for understanding the roles of miRNAs in innate immunity of invertebrate. PMID:29230209

  17. Stimulation of poliovirus RNA synthesis and virus maturation in a HeLa cell-free in vitro translation-RNA replication system by viral protein 3CDpro

    Directory of Open Access Journals (Sweden)

    Wimmer Eckard

    2005-11-01

    Full Text Available Abstract Poliovirus protein 3CDpro possesses both proteinase and RNA binding activities, which are located in the 3Cpro domain of the protein. The RNA polymerase (3Dpol domain of 3CDpro modulates these activities of the protein. We have recently shown that the level of 3CDpro in HeLa cell-free in vitro translation-RNA replication reactions is suboptimal for efficient virus production. However, the addition of either 3CDpro mRNA or of purified 3CDpro protein to in vitro reactions, programmed with viral RNA, results in a 100-fold increase in virus yield. Mutational analyses of 3CDpro indicated that RNA binding by the 3Cpro domain and the integrity of interface I in the 3Dpol domain of the protein are both required for function. The aim of these studies was to determine the exact step or steps at which 3CDpro enhances virus yield and to determine the mechanism by which this occurs. Our results suggest that the addition of extra 3CDpro to in vitro translation RNA-replication reactions results in a mild enhancement of both minus and plus strand RNA synthesis. By examining the viral particles formed in the in vitro reactions on sucrose gradients we determined that 3CDpro has only a slight stimulating effect on the synthesis of capsid precursors but it strikingly enhances the maturation of virus particles. Both the stimulation of RNA synthesis and the maturation of the virus particles are dependent on the presence of an intact RNA binding site within the 3Cpro domain of 3CDpro. In addition, the integrity of interface I in the 3Dpol domain of 3CDpro is required for efficient production of mature virus. Surprisingly, plus strand RNA synthesis and virus production in in vitro reactions, programmed with full-length transcript RNA, are not enhanced by the addition of extra 3CDpro. Our results indicate that the stimulation of RNA synthesis and virus maturation by 3CDpro in vitro is dependent on the presence of a VPg-linked RNA template.

  18. Selective translational repression of HIV-1 RNA by Sam68DeltaC occurs by altering PABP1 binding to unspliced viral RNA

    Directory of Open Access Journals (Sweden)

    Soros Vanessa

    2008-10-01

    Full Text Available Abstract HIV-1 structural proteins are translated from incompletely spliced 9 kb and 4 kb mRNAs, which are transported to the cytoplasm by Crm1. It has been assumed that once in the cytoplasm, translation of incompletely spliced HIV-1 mRNAs occurs in the same manner as host mRNAs. Previous analyses have demonstrated that Sam68 and a mutant thereof, Sam68ΔC, have dramatic effects on HIV gene expression, strongly enhancing and inhibiting viral structural protein synthesis, respectively. While investigating the inhibition of incompletely spliced HIV-1 mRNAs by Sam68ΔC, we determined that the effect was independent of the perinuclear bundling of the viral RNA. Inhibition was dependent upon the nuclear export pathway used, as translation of viral RNA exported via the Tap/CTE export pathway was not blocked by Sam68ΔC. We demonstrate that inhibition of HIV expression by Sam68ΔC is correlated with a loss of PABP1 binding with no attendant change in polyadenosine tail length of the affected RNAs. The capacity of Sam68ΔC to selectively inhibit translation of HIV-1 RNAs exported by Crm1 suggests that it is able to recognize unique characteristics of these viral RNPs, a property that could lead to new therapeutic approaches to controlling HIV-1 replication.

  19. Characterization of a defective interfering RNA that contains a mosaic of a plant viral genome. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Morris, T.J.; Jackson, A.O.

    1991-12-31

    Our lab was the first to describe and characterize a defective interfering RNA (DI RNAs or DIs) in association with a small RNA plant virus. The features of the DIs that we discovered in infections of tomato bushy stunt virus were compatible with the properties of DIs identified in many animal virus infections. Animal virologists have generally recognized the importance of studying DIs because they are invaluable tools for identifying cis-acting sequences important in virus multiplication and because they offer the opportunity to elucidate mechanisms involved in viral persistence and disease attenuation. Hence our discovery offered a comparably valuable tool for use in plant virus studies for the first time. Since then, we have also discovered the second example of plant viral DI RNAs associated with turnip crinkle virus (TCV), a virus structurally related to TBSV. We proposed a thorough characterization of this unique class of symptom modulating RNAs with the overall objective of identifying viral RNA nucleotide, sequences involved in such fundamental processes as virus replication and encapsidation as well as the degree of symptom expression resulting from the viral-DI-host interaction. The proposed research focused on the molecular characterization of the DI RNAs and the helper virus. We had demonstrated that the DIs were collinear deletion mutants of the genome of a cherry strain of tomato bushy stunt virus (TBSV). We had also shown that these low molecular weight RNAs interfered with the helper plant virus and modulated disease expression by preventing the development of a lethal necrotic disease in susceptible host plants. We also suggested that by exploring the mechanisms associated with the symptom attenuation effect, we might be able to devise novel strategies useful for engineering viral disease resistance.

  20. Distinct binding interactions of HIV-1 Gag to Psi and non-Psi RNAs: implications for viral genomic RNA packaging.

    Science.gov (United States)

    Webb, Joseph A; Jones, Christopher P; Parent, Leslie J; Rouzina, Ioulia; Musier-Forsyth, Karin

    2013-08-01

    Despite the vast excess of cellular RNAs, precisely two copies of viral genomic RNA (gRNA) are selectively packaged into new human immunodeficiency type 1 (HIV-1) particles via specific interactions between the HIV-1 Gag and the gRNA psi (ψ) packaging signal. Gag consists of the matrix (MA), capsid, nucleocapsid (NC), and p6 domains. Binding of the Gag NC domain to ψ is necessary for gRNA packaging, but the mechanism by which Gag selectively interacts with ψ is unclear. Here, we investigate the binding of NC and Gag variants to an RNA derived from ψ (Psi RNA), as well as to a non-ψ region (TARPolyA). Binding was measured as a function of salt to obtain the effective charge (Zeff) and nonelectrostatic (i.e., specific) component of binding, Kd(1M). Gag binds to Psi RNA with a dramatically reduced Kd(1M) and lower Zeff relative to TARPolyA. NC, GagΔMA, and a dimerization mutant of Gag bind TARPolyA with reduced Zeff relative to WT Gag. Mutations involving the NC zinc finger motifs of Gag or changes to the G-rich NC-binding regions of Psi RNA significantly reduce the nonelectrostatic component of binding, leading to an increase in Zeff. These results show that Gag interacts with gRNA using different binding modes; both the NC and MA domains are bound to RNA in the case of TARPolyA, whereas binding to Psi RNA involves only the NC domain. Taken together, these results suggest a novel mechanism for selective gRNA encapsidation.

  1. APOBEC3G inhibits HIV-1 RNA elongation by inactivating the viral trans-activation response element.

    Science.gov (United States)

    Nowarski, Roni; Prabhu, Ponnandy; Kenig, Edan; Smith, Yoav; Britan-Rosich, Elena; Kotler, Moshe

    2014-07-29

    Deamination of cytidine residues in viral DNA is a major mechanism by which APOBEC3G (A3G) inhibits vif-deficient human immunodeficiency virus type 1 (HIV-1) replication. dC-to-dU transition following RNase-H activity leads to viral cDNA degradation, production of non-functional proteins, formation of undesired stop codons and decreased viral protein synthesis. Here, we demonstrate that A3G provides an additional layer of defense against HIV-1 infection dependent on inhibition of proviral transcription. HIV-1 transcription elongation is regulated by the trans-activation response (TAR) element, a short stem-loop RNA structure required for elongation factors binding. Vif-deficient HIV-1-infected cells accumulate short viral transcripts and produce lower amounts of full-length HIV-1 transcripts due to A3G deamination of the TAR apical loop cytidine, highlighting the requirement for TAR loop integrity in HIV-1 transcription. We further show that free single-stranded DNA (ssDNA) termini are not essential for A3G activity and a gap of CCC motif blocked with juxtaposed DNA or RNA on either or 3'+5' ends is sufficient for A3G deamination. These results identify A3G as an efficient mutator and that deamination of (-)SSDNA results in an early block of HIV-1 transcription. Copyright © 2014 Elsevier Ltd. All rights reserved.

  2. Viral kinetics of hepatitis C virus RNA in patients with chronic hepatitis C treated with 18 MU of interferon alpha daily

    NARCIS (Netherlands)

    Sentjens, Roel E.; Weegink, Christine J.; Beld, Marcel G.; Cooreman, Michel C.; Reesink, Henk W.

    2002-01-01

    BACKGROUND: A rapid decrease of hepatitis C virus (HCV) RNA is interferon (IFN) dose-dependent, and a 3-log decline of HCV-RNA is a strong predictor of sustained virological response. In this study, viral kinetics of HCV RNA in patients treated with 18 MU interferon alpha (IFN-alpha) daily for 2

  3. Viral Delivery of dsRNA for Control of Insect Agricultural Pests and Vectors of Human Disease: Prospects and Challenges

    Directory of Open Access Journals (Sweden)

    Anna Kolliopoulou

    2017-06-01

    Full Text Available RNAi is applied as a new and safe method for pest control in agriculture but efficiency and specificity of delivery of dsRNA trigger remains a critical issue. Various agents have been proposed to augment dsRNA delivery, such as engineered micro-organisms and synthetic nanoparticles, but the use of viruses has received relatively little attention. Here we present a critical view of the potential of the use of recombinant viruses for efficient and specific delivery of dsRNA. First of all, it requires the availability of plasmid-based reverse genetics systems for virus production, of which an overview is presented. For RNA viruses, their application seems to be straightforward since dsRNA is produced as an intermediate molecule during viral replication, but DNA viruses also have potential through the production of RNA hairpins after transcription. However, application of recombinant virus for dsRNA delivery may not be straightforward in many cases, since viruses can encode RNAi suppressors, and virus-induced silencing effects can be determined by the properties of the encoded RNAi suppressor. An alternative is virus-like particles that retain the efficiency and specificity determinants of natural virions but have encapsidated non-replicating RNA. Finally, the use of viruses raises important safety issues which need to be addressed before application can proceed.

  4. RNA viral metagenome of whiteflies leads to the discovery and characterization of a whitefly-transmitted carlavirus in North America.

    Science.gov (United States)

    Rosario, Karyna; Capobianco, Heather; Ng, Terry Fei Fan; Breitbart, Mya; Polston, Jane E

    2014-01-01

    Whiteflies from the Bemisia tabaci species complex have the ability to transmit a large number of plant viruses and are some of the most detrimental pests in agriculture. Although whiteflies are known to transmit both DNA and RNA viruses, most of the diversity has been recorded for the former, specifically for the Begomovirus genus. This study investigated the total diversity of DNA and RNA viruses found in whiteflies collected from a single site in Florida to evaluate if there are additional, previously undetected viral types within the B. tabaci vector. Metagenomic analysis of viral DNA extracted from the whiteflies only resulted in the detection of begomoviruses. In contrast, whiteflies contained sequences similar to RNA viruses from divergent groups, with a diversity that extends beyond currently described viruses. The metagenomic analysis of whiteflies also led to the first report of a whitefly-transmitted RNA virus similar to Cowpea mild mottle virus (CpMMV Florida) (genus Carlavirus) in North America. Further investigation resulted in the detection of CpMMV Florida in native and cultivated plants growing near the original field site of whitefly collection and determination of its experimental host range. Analysis of complete CpMMV Florida genomes recovered from whiteflies and plants suggests that the current classification criteria for carlaviruses need to be reevaluated. Overall, metagenomic analysis supports that DNA plant viruses carried by B. tabaci are dominated by begomoviruses, whereas significantly less is known about RNA viruses present in this damaging insect vector.

  5. RNA viral metagenome of whiteflies leads to the discovery and characterization of a whitefly-transmitted carlavirus in North America.

    Directory of Open Access Journals (Sweden)

    Karyna Rosario

    Full Text Available Whiteflies from the Bemisia tabaci species complex have the ability to transmit a large number of plant viruses and are some of the most detrimental pests in agriculture. Although whiteflies are known to transmit both DNA and RNA viruses, most of the diversity has been recorded for the former, specifically for the Begomovirus genus. This study investigated the total diversity of DNA and RNA viruses found in whiteflies collected from a single site in Florida to evaluate if there are additional, previously undetected viral types within the B. tabaci vector. Metagenomic analysis of viral DNA extracted from the whiteflies only resulted in the detection of begomoviruses. In contrast, whiteflies contained sequences similar to RNA viruses from divergent groups, with a diversity that extends beyond currently described viruses. The metagenomic analysis of whiteflies also led to the first report of a whitefly-transmitted RNA virus similar to Cowpea mild mottle virus (CpMMV Florida (genus Carlavirus in North America. Further investigation resulted in the detection of CpMMV Florida in native and cultivated plants growing near the original field site of whitefly collection and determination of its experimental host range. Analysis of complete CpMMV Florida genomes recovered from whiteflies and plants suggests that the current classification criteria for carlaviruses need to be reevaluated. Overall, metagenomic analysis supports that DNA plant viruses carried by B. tabaci are dominated by begomoviruses, whereas significantly less is known about RNA viruses present in this damaging insect vector.

  6. Viral RNA annealing activities of human immunodeficiency virus type 1 nucleocapsid protein require only peptide domains outside the zinc fingers.

    Science.gov (United States)

    De Rocquigny, H; Gabus, C; Vincent, A; Fournié-Zaluski, M C; Roques, B; Darlix, J L

    1992-07-15

    The nucleocapsid (NC) of human immunodeficiency virus type 1 consists of a large number of NC protein molecules, probably wrapping the dimeric RNA genome within the virion inner core. NC protein is a gag-encoded product that contains two zinc fingers flanked by basic residues. In human immunodeficiency virus type 1 virions, NCp15 is ultimately processed into NCp7 and p6 proteins. During virion assembly the retroviral NC protein is necessary for core formation and genomic RNA encapsidation, which are essential for virus infectivity. In vitro NCp15 activates viral RNA dimerization, a process most probably linked in vivo to genomic RNA packaging, and replication primer tRNA(Lys,3) annealing to the initiation site of reverse transcription. To characterize the domains of human immunodeficiency virus type 1 NC protein necessary for its various functions, the 72-amino acid NCp7 and several derived peptides were synthesized in a pure form. We show here that synthetic NCp7 with or without the two zinc fingers has the RNA annealing activities of NCp15. Further deletions of the N-terminal 12 and C-terminal 8 amino acids, leading to a 27-residue peptide lacking the finger domains, have little or no effect on NC protein activity in vitro. However deletion of short sequences containing basic residues flanking the first finger leads to a complete loss of NC protein activity. It is proposed that the basic residues and the zinc fingers cooperate to select and package the genomic RNA in vivo. Inhibition of the viral RNA binding and annealing activities associated with the basic residues flanking the first zinc finger of NC protein could therefore be used as a model for the design of antiviral agents.

  7. Porcine Reproductive and Respiratory Syndrome Virus Nucleocapsid Protein Interacts with Nsp9 and Cellular DHX9 To Regulate Viral RNA Synthesis.

    Science.gov (United States)

    Liu, Long; Tian, Jiao; Nan, Hao; Tian, Mengmeng; Li, Yuan; Xu, Xiaodong; Huang, Baicheng; Zhou, Enmin; Hiscox, Julian A; Chen, Hongying

    2016-06-01

    Porcine reproductive and respiratory syndrome virus (PRRSV) nucleocapsid (N) protein is the main component of the viral capsid to encapsulate viral RNA, and it is also a multifunctional protein involved in the regulation of host cell processes. Nonstructural protein 9 (Nsp9) is the RNA-dependent RNA polymerase that plays a critical role in viral RNA transcription and replication. In this study, we demonstrate that PRRSV N protein is bound to Nsp9 by protein-protein interaction and that the contacting surface on Nsp9 is located in the two predicted α-helixes formed by 48 residues at the C-terminal end of the protein. Mutagenesis analyses identified E646, E608, and E611 on Nsp9 and Q85 on the N protein as the pivotal residues participating in the N-Nsp9 interaction. By overexpressing the N protein binding fragment of Nsp9 in infected Marc-145 cells, the synthesis of viral RNAs, as well as the production of infectious progeny viruses, was dramatically inhibited, suggesting that Nsp9-N protein association is involved in the process of viral RNA production. In addition, we show that PRRSV N interacts with cellular RNA helicase DHX9 and redistributes the protein into the cytoplasm. Knockdown of DHX9 increased the ratio of short subgenomic mRNAs (sgmRNAs); in contrast, DHX9 overexpression benefited the synthesis of longer sgmRNAs and the viral genomic RNA (gRNA). These results imply that DHX9 is recruited by the N protein in PRRSV infection to regulate viral RNA synthesis. We postulate that N and DHX9 may act as antiattenuation factors for the continuous elongation of nascent transcript during negative-strand RNA synthesis. It is unclear whether the N protein of PRRSV is involved in regulation of the viral RNA production process. In this report, we demonstrate that the N protein of the arterivirus PRRSV participates in viral RNA replication and transcription through interacting with Nsp9 and its RdRp and recruiting cellular RNA helicase to promote the production of

  8. The 3D protein of duck hepatitis A virus type 1 binds to a viral genomic 3' UTR and shows RNA-dependent RNA polymerase activity.

    Science.gov (United States)

    Zhang, Yu; Cao, Qianda; Wang, Mingshu; Jia, Renyong; Chen, Shun; Zhu, Dekang; Liu, Mafeng; Sun, Kunfeng; Yang, Qiao; Wu, Ying; Zhao, Xinxin; Chen, Xiaoyue; Cheng, Anchun

    2017-12-01

    To explore the RNA-dependent RNA polymerase (RdRP) function of the 3D protein of duck hepatitis A virus type 1 (DHAV-1), the gene was cloned into the pET-32a(+) vector for prokaryotic expression. The 3' untranslated region (3' UTR) of DHAV-1 together with a T7 promoter was cloned into the pMD19-T vector for in vitro transcription of 3' UTR RNA, which was further used as a template in RNA-dependent RNA polymerization. In this study, three methods were applied to analyze the RdRP function of the 3D protein: (1) ammonium molybdate spectrophotometry to detect pyrophosphate produced during polymerization; (2) quantitative reverse transcription PCR (RT-qPCR) to investigate the changes in RNA quantity during polymerization; and (3) electrophoresis mobility shift assay to examine the interaction between the 3D protein and 3' UTR. The results showed the 3D protein was successfully expressed in bacteria culture supernatant in a soluble form, which could be purified by affinity chromatography. In 3D enzymatic activity assays, pyrophosphate and RNA were produced, the amounts of which increased based on approximative kinetics, and binding of the 3D protein to the 3' UTR was observed. These results indicate that prokaryotically expressed soluble DHAV-13D protein can bind to a viral genomic 3' UTR and exhibit RdRP activity.

  9. Virological and immunological profiles among patients with undetectable viral load followed prospectively for 24 months

    DEFF Research Database (Denmark)

    Katzenstein, T.; Ullum, H.; Røge, B.T.

    2003-01-01

    OBJECTIVE: To quantify HIV-RNA in plasma, in lymphoid tissue and proviral DNA in peripheral blood mononuclear cells and to relate these to immunological markers among patients with plasma viral load counts of

  10. [ALAT and viral RNA as risk factors in 68 blood donors with anti-hepatitis C antibodies].

    Science.gov (United States)

    Tullen, E; De Saussure, P; Soulier-Lauper, M

    1993-01-23

    Determine the risk factors in blood donors with anti hepatitis C antibodies (anti-HCV ab) possible liver involvement and evaluation of their infectious potential by a search for viral RNA in blood. Between July 1990 and October 1991, 19,632 blood donors were screened for hepatitis C. Antibodies to HCV were detected in 74 donors (2nd generation ELISA, Abbott). We evaluated the risk factors, determined ALAT levels and looked for circulating RNA virus by amplification of the non-coding region of the viral genome (RTPCR) in 68 of these 74 donors screened. A control was chosen arbitrarily from 103 donors with high ALAT levels, but with no antibodies to HCV nor detectable circulating viral DNA. The prevalence of anti-HCV ab in blood donors in 0.37%. No risk factor was found in 29 donors (43%). Parenteral exposure (former i.v. drug addiction and history of transfusions) was found to be the mode of transmission of hepatitis C in 23 donors (34%). History of NANB jaundice (non-post transfusion) was reported in 1 donor (1%). The remaining 15 donors (22%) were found to have minor risk factors - either isolated or in combination (exposure, tatoos, multiple sexual partners). Former i.v. drug addiction (p = 0.0000006) as well as a history of transfusions (p = 0.0071) are significantly more frequent in the group of donors with antibodies to HCV. None of the 35 sexual partners of the tested donors proved to be positive. 21 donors (30%) had high ALAT (+2 SD). Viral RNA was detected in blood of 26 donors (38%). The proportion of cases with positive viral RNA was 61% if only those donors with high ALAT levels were taken into consideration (13 positive of 21). Risk factors were found in 39 donors (57%) with antibodies to HCV. History of parenteral exposure was found to be significantly more frequent than in the control group (p = 0.0000054). Sexual transmission within couples was not demonstrated in the population tested. A positive PCR test is a probable indicator of a continuous

  11. Presence of viral RNA and proteins in exosomes from the cellular clones resistant to Rift Valley Fever Virus infection.

    Directory of Open Access Journals (Sweden)

    Noor eAhsan

    2016-02-01

    Full Text Available Rift Valley Fever Virus (RVFV is a RNA virus that belongs to the genus Phlebovirus, family Bunyaviridae. It infects humans and livestock and causes Rift Valley fever. RVFV is considered an agricultural pathogen by the USDA, as it can cause up to 100% abortion in cattle and extensive death of newborns. In addition, it is designated as Category A pathogen by the CDC and the NIAID. In some human cases of RVFV infection, the virus causes fever, ocular damage, liver damage, hemorrhagic fever, and death. There are currently limited options for vaccine candidates, which include the MP-12 and clone 13 versions of RVFV. Viral infections often deregulate multiple cellular pathways that contribute to replication and host pathology. We have previously shown that latent HIV-1 and HTLV-1 infected cells secrete exosomes that contain short viral RNAs, limited number of genomic RNAs, and viral proteins. These exosomes largely target neighboring cells and activate the NF-кB pathway, leading to cell proliferation and overall better viral replication. In this manuscript, we studied the effects of exosome formation from RVFV infected cells and their function on recipient cells. We initially infected cells, isolated resistant clones, and further purified using dilution cloning. We then characterized these cells as resistant to new RVFV infection, but sensitive to other viral infections, including Venezuelan Equine Encephalitis Virus (VEEV. These clones contained normal markers (i.e. CD63 for exosomes and were able to activate the TLR pathway in recipient reporter cells. Interestingly, the exosome rich preparations, much like their host cell, contained viral RNA (L, M, and S genome. The RNAs were detected using qRT-PCR in both parental and exosomal preparations as well as in CD63 immunoprecipitates. Viral proteins such as N and a modified form of NSs were present in some of these exosomes. Finally, treatment of recipient cells (T- cells and monocytic cells showed

  12. Factors influencing cerebrospinal fluid and plasma HIV-1 RNA detection rate in patients with and without opportunistic neurological disease during the HAART era

    Directory of Open Access Journals (Sweden)

    Aleixo Agdemir W

    2007-12-01

    Full Text Available Abstract Background In the central nervous system, HIV replication can occur relatively independent of systemic infection, and intrathecal replication of HIV-1 has been observed in patients with HIV-related and opportunistic neurological diseases. The clinical usefulness of HIV-1 RNA detection in the cerebrospinal fluid (CSF of patients with opportunistic neurological diseases, or the effect of opportunistic diseases on CSF HIV levels in patients under HAART has not been well defined. We quantified CSF and plasma viral load in HIV-infected patients with and without different active opportunistic neurological diseases, determined the characteristics that led to a higher detection rate of HIV RNA in CSF, and compared these two compartments. Methods A prospective study was conducted on 90 HIV-infected patients submitted to lumbar puncture as part of a work-up for suspected neurological disease. Seventy-one patients had active neurological diseases while the remaining 19 did not. Results HIV-1 RNA was quantified in 90 CSF and 70 plasma samples. The HIV-1 RNA detection rate in CSF was higher in patients with neurological diseases, in those with a CD4 count lower than 200 cells/mm3, and in those not receiving antiretroviral therapy, as well as in patients with detectable plasma HIV-1 RNA. Median viral load was lower in CSF than in plasma in the total population, in patients without neurological diseases, and in patients with toxoplasmic encephalitis, while no significant difference between the two compartments was observed for patients with cryptococcal meningitis and HIV-associated dementia. CSF viral load was lower in patients with cryptococcal meningitis and neurotoxoplasmosis under HAART than in those not receiving HAART. Conclusion Detection of HIV-1 RNA in CSF was more frequent in patients with neurological disease, a CD4 count lower than 200 cells/mm3 and detectable plasma HIV-1. Median HIV-1 RNA levels were generally lower in CSF than in

  13. Mutational analysis of the hypervariable region of hepatitis e virus reveals its involvement in the efficiency of viral RNA replication.

    Science.gov (United States)

    Pudupakam, R S; Kenney, Scott P; Córdoba, Laura; Huang, Yao-Wei; Dryman, Barbara A; Leroith, Tanya; Pierson, F William; Meng, Xiang-Jin

    2011-10-01

    The RNA genome of the hepatitis E virus (HEV) contains a hypervariable region (HVR) in ORF1 that tolerates small deletions with respect to infectivity. To further investigate the role of the HVR in HEV replication, we constructed a panel of mutants with overlapping deletions in the N-terminal, central, and C-terminal regions of the HVR by using a genotype 1 human HEV luciferase replicon and analyzed the effects of deletions on viral RNA replication in Huh7 cells. We found that the replication levels of the HVR deletion mutants were markedly reduced in Huh7 cells, suggesting a role of the HVR in viral replication efficiency. To further verify the results, we constructed HVR deletion mutants by using a genetically divergent, nonmammalian avian HEV, and similar effects on viral replication efficiency were observed when the avian HEV mutants were tested in LMH cells. Furthermore, the impact of complete HVR deletion on virus infectivity was tested in chickens, using an avian HEV mutant with a complete HVR deletion. Although the deletion mutant was still replication competent in LMH cells, the complete HVR deletion resulted in a loss of avian HEV infectivity in chickens. Since the HVR exhibits extensive variations in sequence and length among different HEV genotypes, we further examined the interchangeability of HVRs and demonstrated that HVR sequences are functionally exchangeable between HEV genotypes with regard to viral replication and infectivity in vitro, although genotype-specific HVR differences in replication efficiency were observed. The results showed that although the HVR tolerates small deletions with regard to infectivity, it may interact with viral and host factors to modulate the efficiency of HEV replication.

  14. Tripartite polyionic complex (PIC) micelles as non-viral vectors for mesenchymal stem cell siRNA transfection.

    Science.gov (United States)

    Raisin, Sophie; Morille, Marie; Bony, Claire; Noël, Danièle; Devoisselle, Jean-Marie; Belamie, Emmanuel

    2017-08-22

    In the context of regenerative medicine, the use of RNA interference mechanisms has already proven its efficiency in targeting specific gene expression with the aim of enhancing, accelerating or, more generally, directing stem cell differentiation. However, achievement of good transfection levels requires the use of a gene vector. For in vivo applications, synthetic vectors are an interesting option to avoid possible issues associated with viral vectors (safety, production costs, etc.). Herein, we report on the design of tripartite polyionic complex micelles as original non-viral polymeric vectors suited for mesenchymal stem cell transfection with siRNA. Three micelle formulations were designed to exhibit pH-triggered disassembly in an acidic pH range comparable to that of endosomes. One formulation was selected as the most promising with the highest siRNA loading capacity while clearly maintaining pH-triggered disassembly properties. A thorough investigation of the internalization pathway of micelles into cells with tagged siRNA was made before showing an efficient inhibition of Runx2 expression in primary bone marrow-derived stem cells. This work evidenced PIC micelles as promising synthetic vectors that allow efficient MSC transfection and control over their behavior, from the perspective of their clinical use.

  15. Forced selection of a human immunodeficiency virus type 1 variant that uses a non-self tRNA primer for reverse transcription: Involvement of viral RNA sequences and the reverse transcriptase enzyme

    NARCIS (Netherlands)

    Abbink, Truus E. M.; Beerens, Nancy; Berkhout, Ben

    2004-01-01

    Human immunodeficiency virus type 1 uses the tRNA(3)(Lys) molecule as a selective primer for reverse transcription. This primer specificity is imposed by sequence complementarity between the tRNA primer and two motifs in the viral RNA genome: the primer-binding site (PBS) and the primer activation

  16. Group 2 coronaviruses prevent immediate early interferon induction by protection of viral RNA from host cell recognition

    International Nuclear Information System (INIS)

    Versteeg, Gijs A.; Bredenbeek, Peter J.; Worm, Sjoerd H.E. van den; Spaan, Willy J.M.

    2007-01-01

    Many viruses encode antagonists to prevent interferon (IFN) induction. Infection of fibroblasts with the murine hepatitis coronavirus (MHV) and SARS-coronavirus (SARS-CoV) did not result in nuclear translocation of interferon-regulatory factor 3 (IRF3), a key transcription factor involved in IFN induction, and induction of IFN mRNA transcription. Furthermore, MHV and SARS-CoV infection could not prevent IFN induction by poly (I:C) or Sendai virus, suggesting that these CoVs do not inactivate IRF3-mediated transcription regulation, but apparently prevent detection of replicative RNA by cellular sensory molecules. Our data indicate that shielding of viral RNA to host cell sensors might be the main general mechanism for coronaviruses to prevent IFN induction

  17. Hsp90 interacts specifically with viral RNA and differentially regulates replication initiation of Bamboo mosaic virus and associated satellite RNA.

    Directory of Open Access Journals (Sweden)

    Ying Wen Huang

    Full Text Available Host factors play crucial roles in the replication of plus-strand RNA viruses. In this report, a heat shock protein 90 homologue of Nicotiana benthamiana, NbHsp90, was identified in association with partially purified replicase complexes from BaMV-infected tissue, and shown to specifically interact with the 3' untranslated region (3' UTR of BaMV genomic RNA, but not with the 3' UTR of BaMV-associated satellite RNA (satBaMV RNA or that of genomic RNA of other viruses, such as Potato virus X (PVX or Cucumber mosaic virus (CMV. Mutational analyses revealed that the interaction occurs between the middle domain of NbHsp90 and domain E of the BaMV 3' UTR. The knockdown or inhibition of NbHsp90 suppressed BaMV infectivity, but not that of satBaMV RNA, PVX, or CMV in N. benthamiana. Time-course analysis further revealed that the inhibitory effect of 17-AAG is significant only during the immediate early stages of BaMV replication. Moreover, yeast two-hybrid and GST pull-down assays demonstrated the existence of an interaction between NbHsp90 and the BaMV RNA-dependent RNA polymerase. These results reveal a novel role for NbHsp90 in the selective enhancement of BaMV replication, most likely through direct interaction with the 3' UTR of BaMV RNA during the initiation of BaMV RNA replication.

  18. MicroRNA Roles in the NF-κB Signaling Pathway during Viral Infections

    Directory of Open Access Journals (Sweden)

    Zeqian Gao

    2014-01-01

    Full Text Available NF-κB signaling network is a crucial component of innate immunity. miRNAs are a subtype of small noncoding RNAs, involved in regulation of gene expression at the posttranscriptional level. Increasing evidence has emerged that miRNAs play an important role in regulation of NF-κB signaling pathway during viral infections. Both host and viral miRNAs are attributed to modulation of NF-κB activity, thus affecting viral infection and clearance. Understandings of the mechanisms of these miRNAs will open a direction for development of novel antivirus drugs.

  19. SH3 domain-mediated recruitment of host cell amphiphysins by alphavirus nsP3 promotes viral RNA replication.

    Directory of Open Access Journals (Sweden)

    Maarit Neuvonen

    2011-11-01

    Full Text Available Among the four non-structural proteins of alphaviruses the function of nsP3 is the least well understood. NsP3 is a component of the viral replication complex, and composed of a conserved aminoterminal macro domain implicated in viral RNA synthesis, and a poorly conserved carboxyterminal region. Despite the lack of overall homology we noted a carboxyterminal proline-rich sequence motif shared by many alphaviral nsP3 proteins, and found it to serve as a preferred target site for the Src-homology 3 (SH3 domains of amphiphysin-1 and -2. Nsp3 proteins of Semliki Forest (SFV, Sindbis (SINV, and Chikungunya viruses all showed avid and SH3-dependent binding to amphiphysins. Upon alphavirus infection the intracellular distribution of amphiphysin was dramatically altered and colocalized with nsP3. Mutations in nsP3 disrupting the amphiphysin SH3 binding motif as well as RNAi-mediated silencing of amphiphysin-2 expression resulted in impaired viral RNA replication in HeLa cells infected with SINV or SFV. Infection of Balb/c mice with SFV carrying an SH3 binding-defective nsP3 was associated with significantly decreased mortality. These data establish SH3 domain-mediated binding of nsP3 with amphiphysin as an important host cell interaction promoting alphavirus replication.

  20. Effects of F virus in Bombyx mori L., 1758 (Lep., bombycidae) and site determination of the viral RNA synthesis by auto-radiography

    International Nuclear Information System (INIS)

    Almeida, I.M.G. de.

    1980-01-01

    Some aspects of the pathological process of the infectious flacherie virus in the midgut epithelial cells of the silkworm (Bombyx mori L., 1758 (Lep., Bombycidae)) as well as the site of the viral RNA synthesis were investigated. Electron microscope observation of these inclusion bodies showed that they were surrounded by a single membrane and containing many vesicles and virus particles. The nucleus of the cells infected with the virus exhibited higher electron dense masses than the healthy ones. The site of the viral RNA synthesis. Actinomycin D, at the used concentration, selectively blocked the cell RNA synthesis without affecting the virus RNA synthesis. The inhibition found was about 60%. The data obtained indicated that the viral RNA synthesis occurs in the nucleus of the midgut epithelial cells of the silkworm larvae. (author)

  1. [Clinical use of virally inactived plasma. The experience of Blood Transfusion Unit in Mantova, Italy].

    Science.gov (United States)

    Lepri, Debora; Capuzzo, Enrico; Mattioli, Anna Vittoria; Dall'Oglio, Daniela; Sgarioto, Vincenzo; Terenziani, Isabella; Caramaschi, Giacomo; Manzato, Franco; Franchini, Massimo

    2013-03-01

    Fresh Frozen Plasma (FFP) is a blood component whose clinical use is widespread worldwide. Transfusion safety of this product is ensured by legally obligatory tests. Although these tests are carried out on each plasma donation, safety levels can be further improved by using some technical procedures, such as, among others, methylene blue (MB) and solvent-detergent (SD) viral inactivation methods. The DMTE (Blood Transfusion Unit) in Mantova has used the pharmaceutical-like SD virally inactivated plasma since 2007 (Plasmasafe, Kedrion) as replacement of the PFC by each single donor. Guidelines for the usage of both products are the same. With the main aim of assessing the therapeutic effectiveness and safety of Plasmasafe, we decided to clinically monitor transfusions performed with this product on patients of the Intensive Care Unit at the city hospital in Mantova. In addition, we controlled some coagulation parameters (PT, aPTT, ATIII, Fibrinogen, PC, PS, FV, FVII, FVIII) before and 24 hours after the Plasmasafe infusion. From a clinical point of view, the use of Plasmasafe always led to a significant reduction, or complete stop, of the bleeding. No transfusion-related adverse events were recorded. As regards, the most relevant laboratory results, a marked increase in the above mentioned hemostatic parameters was detected. Furthermore, patients transfused with this product received a mean volume significantly lower than an historical cohort of patients treated with FFP (503 mL with Plasmasafe versus 1549 mL with FFP, Pcost-effective treatment, able to rapidly correct hemostatic abnormalities, for critical patients.

  2. Structure and assembly of the essential RNA ring component of a viral DNA packaging motor.

    Science.gov (United States)

    Ding, Fang; Lu, Changrui; Zhao, Wei; Rajashankar, Kanagalaghatta R; Anderson, Dwight L; Jardine, Paul J; Grimes, Shelley; Ke, Ailong

    2011-05-03

    Prohead RNA (pRNA) is an essential component in the assembly and operation of the powerful bacteriophage 29 DNA packaging motor. The pRNA forms a multimeric ring via intermolecular base-pairing interactions between protomers that serves to guide the assembly of the ring ATPase that drives DNA packaging. Here we report the quaternary structure of this rare multimeric RNA at 3.5 Å resolution, crystallized as tetrameric rings. Strong quaternary interactions and the inherent flexibility helped rationalize how free pRNA is able to adopt multiple oligomerization states in solution. These characteristics also allowed excellent fitting of the crystallographic pRNA protomers into previous prohead/pRNA cryo-EM reconstructions, supporting the presence of a pentameric, but not hexameric, pRNA ring in the context of the DNA packaging motor. The pentameric pRNA ring anchors itself directly to the phage prohead by interacting specifically with the fivefold symmetric capsid structures that surround the head-tail connector portal. From these contacts, five RNA superhelices project from the pRNA ring, where they serve as scaffolds for binding and assembly of the ring ATPase, and possibly mediate communication between motor components. Construction of structure-based designer pRNAs with little sequence similarity to the wild-type pRNA were shown to fully support the packaging of 29 DNA.

  3. Inhibition of bovine viral diarrhea virus RNA synthesis by thiosemicarbazone derived from 5,6-dimethoxy-1-indanone.

    Science.gov (United States)

    Castro, Eliana F; Fabian, Lucas E; Caputto, María E; Gagey, Dolores; Finkielsztein, Liliana M; Moltrasio, Graciela Y; Moglioni, Albertina G; Campos, Rodolfo H; Cavallaro, Lucía V

    2011-06-01

    In the present work, we described the activity of the thiosemicarbazone derived from 5,6-dimethoxy-1-indanone (TSC), which we previously characterized as a new compound that inhibits bovine viral diarrhea virus (BVDV) infection. We showed that TSC acts at a point of time that coincides with the onset of viral RNA synthesis and that it inhibits the activity of BVDV replication complexes (RCs). Moreover, we have selected five BVDV mutants that turned out to be highly resistant to TSC but still susceptible to ribavirin (RBV). Four of these resistant mutants carried an N264D mutation in the viral RNA-dependent RNA polymerase (RdRp). The remaining mutant showed an A392E mutation within the same protein. Some of these mutants replicated slower than the wild-type (wt) virus in the absence of TSC, whereas others showed a partial reversion to the wt phenotype over several passages in the absence of the compound. The docking of TSC in the crystal structure of the BVDV RdRp revealed a close contact between the indane ring of the compound and several residues within the fingers domain of the enzyme, some hydrophobic contacts, and hydrogen bonds with the thiosemicarbazone group. Finally, in the mutated RdRp from resistant BVDV, these interactions with TSC could not be achieved. Interestingly, TSC inhibited BVDV replication in cell culture synergistically with RBV. In conclusion, TSC emerges as a new nonnucleoside inhibitor of BVDV RdRp that is synergistic with RBV, a feature that turns it into a potential compound to be evaluated against hepatitis C virus (HCV).

  4. Inhibition of Bovine Viral Diarrhea Virus RNA Synthesis by Thiosemicarbazone Derived from 5,6-Dimethoxy-1-Indanone▿

    Science.gov (United States)

    Castro, Eliana F.; Fabian, Lucas E.; Caputto, María E.; Gagey, Dolores; Finkielsztein, Liliana M.; Moltrasio, Graciela Y.; Moglioni, Albertina G.; Campos, Rodolfo H.; Cavallaro, Lucía V.

    2011-01-01

    In the present work, we described the activity of the thiosemicarbazone derived from 5,6-dimethoxy-1-indanone (TSC), which we previously characterized as a new compound that inhibits bovine viral diarrhea virus (BVDV) infection. We showed that TSC acts at a point of time that coincides with the onset of viral RNA synthesis and that it inhibits the activity of BVDV replication complexes (RCs). Moreover, we have selected five BVDV mutants that turned out to be highly resistant to TSC but still susceptible to ribavirin (RBV). Four of these resistant mutants carried an N264D mutation in the viral RNA-dependent RNA polymerase (RdRp). The remaining mutant showed an A392E mutation within the same protein. Some of these mutants replicated slower than the wild-type (wt) virus in the absence of TSC, whereas others showed a partial reversion to the wt phenotype over several passages in the absence of the compound. The docking of TSC in the crystal structure of the BVDV RdRp revealed a close contact between the indane ring of the compound and several residues within the fingers domain of the enzyme, some hydrophobic contacts, and hydrogen bonds with the thiosemicarbazone group. Finally, in the mutated RdRp from resistant BVDV, these interactions with TSC could not be achieved. Interestingly, TSC inhibited BVDV replication in cell culture synergistically with RBV. In conclusion, TSC emerges as a new nonnucleoside inhibitor of BVDV RdRp that is synergistic with RBV, a feature that turns it into a potential compound to be evaluated against hepatitis C virus (HCV). PMID:21430053

  5. Levels and patterns of HIV RNA viral load in untreated pregnant women

    DEFF Research Database (Denmark)

    NN, NN; Patel, Deven; Thorne, Claire

    2008-01-01

    OBJECTIVE: To assess pregnancy levels and patterns of HIV RNA in the absence of antiretroviral therapy, while appropriately adjusting for potential confounders, including maternal immune status and race. METHODS: Data on > or = 1 antenatal HIV RNA measurements were available for 333 untreated HIV......-infected pregnant women enrolled in the European Collaborative Study. CD4 counts and HIV RNA measurements were routinely collected from 1992 and 1998, respectively. Linear mixed effects models based on 246 women for whom complete data were available examined changes in HIV RNA levels over pregnancy, with a nested...... random effects term accounting for measurement variability within women and period of sample collection. RESULTS: The change in HIV RNA over pregnancy varied significantly by race (p=0.005): from the second trimester until delivery, HIV RNA decreased significantly by an estimated 0.019 log(10) copies...

  6. Development of a challenge-protective vaccine concept by modification of the viral RNA-dependent RNA polymerase of canine distemper virus.

    Science.gov (United States)

    Silin, D; Lyubomska, O; Ludlow, M; Duprex, W P; Rima, B K

    2007-12-01

    We demonstrate that insertion of the open reading frame of enhanced green fluorescent protein (EGFP) into the coding sequence for the second hinge region of the viral L (large) protein (RNA-dependent RNA polymerase) attenuates a wild-type canine distemper virus. Moreover, we show that single intranasal immunization with this recombinant virus provides significant protection against challenge with the virulent parental virus. Protection against wild-type challenge was gained either after recovery of cellular immunity postimmunization or after development of neutralizing antibodies. Insertion of EGFP seems to result in overattenuation of the virus, while our previous experiments demonstrated that the insertion of an epitope tag into a similar position did not affect L protein function. Thus, a desirable level of attenuation could be reached by manipulating the length of the insert (in the second hinge region of the L protein), providing additional tools for optimization of controlled attenuation. This strategy for controlled attenuation may be useful for a "quick response" in vaccine development against well-known and "new" viral infections and could be combined efficiently with other strategies of vaccine development and delivery systems.

  7. Latent viral reactivation is associated with changes in plasma antimicrobial protein concentrations during long-duration spaceflight

    Science.gov (United States)

    Spielmann, G.; Laughlin, M. S.; Kunz, H.; Crucian, B. E.; Quiriarte, H. D.; Mehta, S. K.; Pierson, D. L.; Simpson, R. J.

    2018-05-01

    Long duration spaceflights are associated with profound dysregulation of the immune system and latent viral reactivations. However, little is known on the impact of long duration spaceflight on innate immunity which raises concerns on crewmembers' ability to fight infections during a mission. The aim of this study was to determine the effects of spaceflight on plasma antimicrobial proteins (AMPs) and how these changes impact latent herpesvirus reactivations. Plasma, saliva and urine samples were obtained from 23 crewmembers before, during and after a 6-month mission on the International Space Station (ISS). Plasma AMP concentrations were determined by ELISA, and saliva Epstein-Barr virus (EBV) and varicella zoster virus (VZV) and urine cytomegalovirus (CMV) DNA levels were quantified by Real-Time PCR. There was a non-significant increase in plasma HNP1-3 and LL-37 during the early and middle stages of the missions, which was significantly associated with changes in viral DNA during and after spaceflight. Plasma HNP1-3 and Lysozyme increased at the late mission stages in astronauts who had exhibited EBV and VZV reactivations during the early flight stages. Following return to Earth and during recovery, HNP1-3 and lysozyme concentrations were associated with EBV and VZV viral DNA levels, reducing the magnitude of viral reactivation. Reductions in plasma LL-37 upon return were associated with greater CMV reactivation. This study shows that biomarkers of innate immunity appeared to be partially restored after 6-months in space and suggests that following adaptation to the space environment, plasma HNP1-3 and lysozyme facilitate the control of EBV and VZV reactivation rate and magnitude in space and upon return on earth. However, the landing-associated decline in plasma LL-37 may enhance the rate of CMV reactivation in astronauts following spaceflight, potentially compromising crewmember health after landing.

  8. Correlation of viral RNA biosynthesis with glucose-6-phosphate dehydrogenase activity and host resistance

    Czech Academy of Sciences Publication Activity Database

    Šindelář, Luděk; Šindelářová, Milada

    2002-01-01

    Roč. 215, - (2002), s. 862-869 ISSN 0032-0935 R&D Projects: GA ČR GA522/99/1264 Institutional research plan: CEZ:AV0Z5038910 Keywords : Glucose 6 phosphate dehydrogenase * Nicotiana (viral infection) * Plant viruses Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.960, year: 2002

  9. Transmissible gastroenteritis coronavirus genome packaging signal is located at the 5' end of the genome and promotes viral RNA incorporation into virions in a replication-independent process.

    Science.gov (United States)

    Morales, Lucia; Mateos-Gomez, Pedro A; Capiscol, Carmen; del Palacio, Lorena; Enjuanes, Luis; Sola, Isabel

    2013-11-01

    Preferential RNA packaging in coronaviruses involves the recognition of viral genomic RNA, a crucial process for viral particle morphogenesis mediated by RNA-specific sequences, known as packaging signals. An essential packaging signal component of transmissible gastroenteritis coronavirus (TGEV) has been further delimited to the first 598 nucleotides (nt) from the 5' end of its RNA genome, by using recombinant viruses transcribing subgenomic mRNA that included potential packaging signals. The integrity of the entire sequence domain was necessary because deletion of any of the five structural motifs defined within this region abrogated specific packaging of this viral RNA. One of these RNA motifs was the stem-loop SL5, a highly conserved motif in coronaviruses located at nucleotide positions 106 to 136. Partial deletion or point mutations within this motif also abrogated packaging. Using TGEV-derived defective minigenomes replicated in trans by a helper virus, we have shown that TGEV RNA packaging is a replication-independent process. Furthermore, the last 494 nt of the genomic 3' end were not essential for packaging, although this region increased packaging efficiency. TGEV RNA sequences identified as necessary for viral genome packaging were not sufficient to direct packaging of a heterologous sequence derived from the green fluorescent protein gene. These results indicated that TGEV genome packaging is a complex process involving many factors in addition to the identified RNA packaging signal. The identification of well-defined RNA motifs within the TGEV RNA genome that are essential for packaging will be useful for designing packaging-deficient biosafe coronavirus-derived vectors and providing new targets for antiviral therapies.

  10. A physical interaction between viral replicase and capsid protein is required for genome-packaging specificity in an RNA virus.

    Science.gov (United States)

    Seo, Jang-Kyun; Kwon, Sun-Jung; Rao, A L N

    2012-06-01

    Genome packaging is functionally coupled to replication in RNA viruses pathogenic to humans (Poliovirus), insects (Flock house virus [FHV]), and plants (Brome mosaic virus [BMV]). However, the underlying mechanism is not fully understood. We have observed previously that in FHV and BMV, unlike ectopically expressed capsid protein (CP), packaging specificity results from RNA encapsidation by CP that has been translated from mRNA produced from replicating genomic RNA. Consequently, we hypothesize that a physical interaction with replicase increases the CP specificity for packaging viral RNAs. We tested this hypothesis by evaluating the molecular interaction between replicase protein and CP using a FHV-Nicotiana benthamiana system. Bimolecular fluorescence complementation in conjunction with fluorescent cellular protein markers and coimmunoprecipitation assays demonstrated that FHV replicase (protein A) and CP physically interact at the mitochondrial site of replication and that this interaction requires the N-proximal region from either amino acids 1 to 31 or amino acids 32 to 50 of the CP. In contrast to the mitochondrial localization of CP derived from FHV replication, ectopic expression displayed a characteristic punctate pattern on the endoplasmic reticulum (ER). This pattern was altered to relocalize the CP throughout the cytoplasm when the C-proximal hydrophobic domain was deleted. Analysis of the packaging phenotypes of the CP mutants defective either in protein A-CP interactions or ER localization suggested that synchronization between protein A-CP interaction and its subcellular localization is imperative to confer packaging specificity.

  11. Differential expression of viral PAMP receptors mRNA in peripheral blood of patients with chronic hepatitis C infection

    Directory of Open Access Journals (Sweden)

    Riñón Marta

    2007-11-01

    Full Text Available Abstract Background Pathogen-associated molecular patterns (PAMP receptors play a key role in the early host response to viruses. In this work, we determined mRNA levels of two members of the Toll-like Receptors family, (TLR3 and TLR7 and the helicase RIG-I, all of three recognizing viral RNA products, in peripheral blood of healthy donors and hepatitis C virus (HCV patients, to observe if their transcripts are altered in this disease. Methods IFN-α, TLR3, TLR7 and RIG-I levels in peripheral blood from healthy controls (n = 18 and chronic HCV patients (n = 18 were quantified by real-time polymerase chain reaction. Results Our results show that IFN-α, TLR3, TLR7 and RIG-I mRNA levels are significantly down-regulated in patients with chronic HCV infection when compared with healthy controls. We also found that the measured levels of TLR3 and TLR7, but not RIG-I, correlated significantly with those of IFN-α Conclusion Monitoring the expression of RNA-sensing receptors like TLR3, TLR7 and RIG-I during the different clinical stages of infection could bring a new source of data about the prognosis of disease.

  12. High-throughput sequencing of human plasma RNA by using thermostable group II intron reverse transcriptases

    Science.gov (United States)

    Qin, Yidan; Yao, Jun; Wu, Douglas C.; Nottingham, Ryan M.; Mohr, Sabine; Hunicke-Smith, Scott; Lambowitz, Alan M.

    2016-01-01

    Next-generation RNA-sequencing (RNA-seq) has revolutionized transcriptome profiling, gene expression analysis, and RNA-based diagnostics. Here, we developed a new RNA-seq method that exploits thermostable group II intron reverse transcriptases (TGIRTs) and used it to profile human plasma RNAs. TGIRTs have higher thermostability, processivity, and fidelity than conventional reverse transcriptases, plus a novel template-switching activity that can efficiently attach RNA-seq adapters to target RNA sequences without RNA ligation. The new TGIRT-seq method enabled construction of RNA-seq libraries from RNA in RNA in 1-mL plasma samples from a healthy individual revealed RNA fragments mapping to a diverse population of protein-coding gene and long ncRNAs, which are enriched in intron and antisense sequences, as well as nearly all known classes of small ncRNAs, some of which have never before been seen in plasma. Surprisingly, many of the small ncRNA species were present as full-length transcripts, suggesting that they are protected from plasma RNases in ribonucleoprotein (RNP) complexes and/or exosomes. This TGIRT-seq method is readily adaptable for profiling of whole-cell, exosomal, and miRNAs, and for related procedures, such as HITS-CLIP and ribosome profiling. PMID:26554030

  13. The HIV-1 Rev/RRE system is required for HIV-1 5' UTR cis elements to augment encapsidation of heterologous RNA into HIV-1 viral particles

    Directory of Open Access Journals (Sweden)

    Ma Hong

    2011-06-01

    Full Text Available Abstract Background The process of HIV-1 genomic RNA (gRNA encapsidation is governed by a number of viral encoded components, most notably the Gag protein and gRNA cis elements in the canonical packaging signal (ψ. Also implicated in encapsidation are cis determinants in the R, U5, and PBS (primer binding site from the 5' untranslated region (UTR. Although conventionally associated with nuclear export of HIV-1 RNA, there is a burgeoning role for the Rev/RRE in the encapsidation process. Pleiotropic effects exhibited by these cis and trans viral components may confound the ability to examine their independent, and combined, impact on encapsidation of RNA into HIV-1 viral particles in their innate viral context. We systematically reconstructed the HIV-1 packaging system in the context of a heterologous murine leukemia virus (MLV vector RNA to elucidate a mechanism in which the Rev/RRE system is central to achieving efficient and specific encapsidation into HIV-1 viral particles. Results We show for the first time that the Rev/RRE system can augment RNA encapsidation independent of all cis elements from the 5' UTR (R, U5, PBS, and ψ. Incorporation of all the 5' UTR cis elements did not enhance RNA encapsidation in the absence of the Rev/RRE system. In fact, we demonstrate that the Rev/RRE system is required for specific and efficient encapsidation commonly associated with the canonical packaging signal. The mechanism of Rev/RRE-mediated encapsidation is not a general phenomenon, since the combination of the Rev/RRE system and 5' UTR cis elements did not enhance encapsidation into MLV-derived viral particles. Lastly, we show that heterologous MLV RNAs conform to transduction properties commonly associated with HIV-1 viral particles, including in vivo transduction of non-dividing cells (i.e. mouse neurons; however, the cDNA forms are episomes predominantly in the 1-LTR circle form. Conclusions Premised on encapsidation of a heterologous RNA into

  14. Transmissible Gastroenteritis Coronavirus Genome Packaging Signal Is Located at the 5′ End of the Genome and Promotes Viral RNA Incorporation into Virions in a Replication-Independent Process

    OpenAIRE

    Morales, Lucia; Mateos-Gomez, Pedro A.; Capiscol, Carmen; del Palacio, Lorena; Enjuanes, Luis; Sola, Isabel

    2013-01-01

    Preferential RNA packaging in coronaviruses involves the recognition of viral genomic RNA, a crucial process for viral particle morphogenesis mediated by RNA-specific sequences, known as packaging signals. An essential packaging signal component of transmissible gastroenteritis coronavirus (TGEV) has been further delimited to the first 598 nucleotides (nt) from the 5′ end of its RNA genome, by using recombinant viruses transcribing subgenomic mRNA that included potential packaging signals. Th...

  15. A positive-strand RNA virus uses alternative protein-protein interactions within a viral protease/cofactor complex to switch between RNA replication and virion morphogenesis.

    Science.gov (United States)

    Dubrau, Danilo; Tortorici, M Alejandra; Rey, Félix A; Tautz, Norbert

    2017-02-01

    The viruses of the family Flaviviridae possess a positive-strand RNA genome and express a single polyprotein which is processed into functional proteins. Initially, the nonstructural (NS) proteins, which are not part of the virions, form complexes capable of genome replication. Later on, the NS proteins also play a critical role in virion formation. The molecular basis to understand how the same proteins form different complexes required in both processes is so far unknown. For pestiviruses, uncleaved NS2-3 is essential for virion morphogenesis while NS3 is required for RNA replication but is not functional in viral assembly. Recently, we identified two gain of function mutations, located in the C-terminal region of NS2 and in the serine protease domain of NS3 (NS3 residue 132), which allow NS2 and NS3 to substitute for uncleaved NS2-3 in particle assembly. We report here the crystal structure of pestivirus NS3-4A showing that the NS3 residue 132 maps to a surface patch interacting with the C-terminal region of NS4A (NS4A-kink region) suggesting a critical role of this contact in virion morphogenesis. We show that destabilization of this interaction, either by alanine exchanges at this NS3/4A-kink interface, led to a gain of function of the NS3/4A complex in particle formation. In contrast, RNA replication and thus replicase assembly requires a stable association between NS3 and the NS4A-kink region. Thus, we propose that two variants of NS3/4A complexes exist in pestivirus infected cells each representing a basic building block required for either RNA replication or virion morphogenesis. This could be further corroborated by trans-complementation studies with a replication-defective NS3/4A double mutant that was still functional in viral assembly. Our observations illustrate the presence of alternative overlapping surfaces providing different contacts between the same proteins, allowing the switch from RNA replication to virion formation.

  16. A positive-strand RNA virus uses alternative protein-protein interactions within a viral protease/cofactor complex to switch between RNA replication and virion morphogenesis

    Science.gov (United States)

    Rey, Félix A.

    2017-01-01

    The viruses of the family Flaviviridae possess a positive-strand RNA genome and express a single polyprotein which is processed into functional proteins. Initially, the nonstructural (NS) proteins, which are not part of the virions, form complexes capable of genome replication. Later on, the NS proteins also play a critical role in virion formation. The molecular basis to understand how the same proteins form different complexes required in both processes is so far unknown. For pestiviruses, uncleaved NS2-3 is essential for virion morphogenesis while NS3 is required for RNA replication but is not functional in viral assembly. Recently, we identified two gain of function mutations, located in the C-terminal region of NS2 and in the serine protease domain of NS3 (NS3 residue 132), which allow NS2 and NS3 to substitute for uncleaved NS2-3 in particle assembly. We report here the crystal structure of pestivirus NS3-4A showing that the NS3 residue 132 maps to a surface patch interacting with the C-terminal region of NS4A (NS4A-kink region) suggesting a critical role of this contact in virion morphogenesis. We show that destabilization of this interaction, either by alanine exchanges at this NS3/4A-kink interface, led to a gain of function of the NS3/4A complex in particle formation. In contrast, RNA replication and thus replicase assembly requires a stable association between NS3 and the NS4A-kink region. Thus, we propose that two variants of NS3/4A complexes exist in pestivirus infected cells each representing a basic building block required for either RNA replication or virion morphogenesis. This could be further corroborated by trans-complementation studies with a replication-defective NS3/4A double mutant that was still functional in viral assembly. Our observations illustrate the presence of alternative overlapping surfaces providing different contacts between the same proteins, allowing the switch from RNA replication to virion formation. PMID:28151973

  17. A positive-strand RNA virus uses alternative protein-protein interactions within a viral protease/cofactor complex to switch between RNA replication and virion morphogenesis.

    Directory of Open Access Journals (Sweden)

    Danilo Dubrau

    2017-02-01

    Full Text Available The viruses of the family Flaviviridae possess a positive-strand RNA genome and express a single polyprotein which is processed into functional proteins. Initially, the nonstructural (NS proteins, which are not part of the virions, form complexes capable of genome replication. Later on, the NS proteins also play a critical role in virion formation. The molecular basis to understand how the same proteins form different complexes required in both processes is so far unknown. For pestiviruses, uncleaved NS2-3 is essential for virion morphogenesis while NS3 is required for RNA replication but is not functional in viral assembly. Recently, we identified two gain of function mutations, located in the C-terminal region of NS2 and in the serine protease domain of NS3 (NS3 residue 132, which allow NS2 and NS3 to substitute for uncleaved NS2-3 in particle assembly. We report here the crystal structure of pestivirus NS3-4A showing that the NS3 residue 132 maps to a surface patch interacting with the C-terminal region of NS4A (NS4A-kink region suggesting a critical role of this contact in virion morphogenesis. We show that destabilization of this interaction, either by alanine exchanges at this NS3/4A-kink interface, led to a gain of function of the NS3/4A complex in particle formation. In contrast, RNA replication and thus replicase assembly requires a stable association between NS3 and the NS4A-kink region. Thus, we propose that two variants of NS3/4A complexes exist in pestivirus infected cells each representing a basic building block required for either RNA replication or virion morphogenesis. This could be further corroborated by trans-complementation studies with a replication-defective NS3/4A double mutant that was still functional in viral assembly. Our observations illustrate the presence of alternative overlapping surfaces providing different contacts between the same proteins, allowing the switch from RNA replication to virion formation.

  18. Dissection of specific binding of HIV-1 Gag to the 'packaging signal' in viral RNA.

    Science.gov (United States)

    Comas-Garcia, Mauricio; Datta, Siddhartha Ak; Baker, Laura; Varma, Rajat; Gudla, Prabhakar R; Rein, Alan

    2017-07-20

    Selective packaging of HIV-1 genomic RNA (gRNA) requires the presence of a cis -acting RNA element called the 'packaging signal' (Ψ). However, the mechanism by which Ψ promotes selective packaging of the gRNA is not well understood. We used fluorescence correlation spectroscopy and quenching data to monitor the binding of recombinant HIV-1 Gag protein to Cy5-tagged 190-base RNAs. At physiological ionic strength, Gag binds with very similar, nanomolar affinities to both Ψ-containing and control RNAs. We challenged these interactions by adding excess competing tRNA; introducing mutations in Gag; or raising the ionic strength. These modifications all revealed high specificity for Ψ. This specificity is evidently obscured in physiological salt by non-specific, predominantly electrostatic interactions. This nonspecific activity was attenuated by mutations in the MA, CA, and NC domains, including CA mutations disrupting Gag-Gag interaction. We propose that gRNA is selectively packaged because binding to Ψ nucleates virion assembly with particular efficiency.

  19. Targeted cleavage of hepatitis E virus 3' end RNA mediated by hammerhead ribozymes inhibits viral RNA replication

    International Nuclear Information System (INIS)

    Sriram, Bandi; Thakral, Deepshi; Panda, Subrat Kumar

    2003-01-01

    The 3' end of hepatitis E virus (HEV) contains cis-acting regulatory element, which plays an important role in viral replication. To develop specific replication inhibitor at the molecular level, mono- and di-hammerhead ribozymes (Rz) were designed and synthesized against the conserved 3' end sequences of HEV, which cleave at nucleotide positions 7125 and 7112/7125, respectively. Di-hammerhead ribozyme with two catalytic motifs in tandem was designed to cleave simultaneously at two sites spaced 13 nucleotides apart, which increases the overall cleavage efficiency and prevents the development of escape mutants. Specific cleavage products were obtained with both the ribozymes in vitro at physiological conditions. The inactive control ribozymes showed no cleavage. The ribozymes showed specific inhibition of HEV 3' end fused-luciferase reporter gene expression by ∼37 and ∼60%, respectively in HepG2 cells. These results demonstrate a feasible approach to inhibit the HEV replication to a limited extent by targeting the cis-acting 3' end of HEV with hammerhead ribozymes

  20. Interaction between the cellular protein eEF1A and the 3'-terminal stem-loop of West Nile virus genomic RNA facilitates viral minus-strand RNA synthesis.

    Science.gov (United States)

    Davis, William G; Blackwell, Jerry L; Shi, Pei-Yong; Brinton, Margo A

    2007-09-01

    RNase footprinting and nitrocellulose filter binding assays were previously used to map one major and two minor binding sites for the cell protein eEF1A on the 3'(+) stem-loop (SL) RNA of West Nile virus (WNV) (3). Base substitutions in the major eEF1A binding site or adjacent areas of the 3'(+) SL were engineered into a WNV infectious clone. Mutations that decreased, as well as ones that increased, eEF1A binding in in vitro assays had a negative effect on viral growth. None of these mutations affected the efficiency of translation of the viral polyprotein from the genomic RNA, but all of the mutations that decreased in vitro eEF1A binding to the 3' SL RNA also decreased viral minus-strand RNA synthesis in transfected cells. Also, a mutation that increased the efficiency of eEF1A binding to the 3' SL RNA increased minus-strand RNA synthesis in transfected cells, which resulted in decreased synthesis of genomic RNA. These results strongly suggest that the interaction between eEF1A and the WNV 3' SL facilitates viral minus-strand synthesis. eEF1A colocalized with viral replication complexes (RC) in infected cells and antibody to eEF1A coimmunoprecipitated viral RC proteins, suggesting that eEF1A facilitates an interaction between the 3' end of the genome and the RC. eEF1A bound with similar efficiencies to the 3'-terminal SL RNAs of four divergent flaviviruses, including a tick-borne flavivirus, and colocalized with dengue virus RC in infected cells. These results suggest that eEF1A plays a similar role in RNA replication for all flaviviruses.

  1. Cytoplasmic translocation of polypyrimidine tract-binding protein and its binding to viral RNA during Japanese encephalitis virus infection inhibits virus replication.

    Directory of Open Access Journals (Sweden)

    Deepika Bhullar

    Full Text Available Japanese encephalitis virus (JEV has a single-stranded, positive-sense RNA genome containing a single open reading frame flanked by the 5'- and 3'-non-coding regions (NCRs. The virus genome replicates via a negative-sense RNA intermediate. The NCRs and their complementary sequences in the negative-sense RNA are the sites for assembly of the RNA replicase complex thereby regulating the RNA synthesis and virus replication. In this study, we show that the 55-kDa polypyrimidine tract-binding protein (PTB interacts in vitro with both the 5'-NCR of the positive-sense genomic RNA--5NCR(+, and its complementary sequence in the negative-sense replication intermediate RNA--3NCR(-. The interaction of viral RNA with PTB was validated in infected cells by JEV RNA co-immunoprecipitation and JEV RNA-PTB colocalization experiments. Interestingly, we observed phosphorylation-coupled translocation of nuclear PTB to cytoplasmic foci that co-localized with JEV RNA early during JEV infection. Our studies employing the PTB silencing and over-expression in cultured cells established an inhibitory role of PTB in JEV replication. Using RNA-protein binding assay we show that PTB competitively inhibits association of JEV 3NCR(- RNA with viral RNA-dependent RNA polymerase (NS5 protein, an event required for the synthesis of the plus-sense genomic RNA. cAMP is known to promote the Protein kinase A (PKA-mediated PTB phosphorylation. We show that cells treated with a cAMP analogue had an enhanced level of phosphorylated PTB in the cytoplasm and a significantly suppressed JEV replication. Data presented here show a novel, cAMP-induced, PTB-mediated, innate host response that could effectively suppress JEV replication in mammalian cells.

  2. Plasma HIV Viral Rebound following Protocol-Indicated Cessation of ART Commenced in Primary and Chronic HIV Infection

    DEFF Research Database (Denmark)

    Hamlyn, Elizabeth; Ewings, Fiona M; Porter, Kholoud

    2012-01-01

    OBJECTIVES: The magnitude of HIV viral rebound following ART cessation has consequences for clinical outcome and onward transmission. We compared plasma viral load (pVL) rebound after stopping ART initiated in primary (PHI) and chronic HIV infection (CHI). DESIGN: Two populations with protocol......VL levels, at a median of 50 (95% CI 48-51) weeks after stopping ART. Four weeks after stopping treatment, although the proportion with pVL≥400 copies/ml was similar (78% PHI versus 79% CHI), levels were 0.45 (95% CI 0.26-0.64) log(10) copies/ml lower for PHI versus CHI, and remained lower up to 48 weeks...

  3. Mutations in matrix and SP1 repair the packaging specificity of a Human Immunodeficiency Virus Type 1 mutant by reducing the association of Gag with spliced viral RNA

    Directory of Open Access Journals (Sweden)

    Ristic Natalia

    2010-09-01

    Full Text Available Abstract Background The viral genome of HIV-1 contains several secondary structures that are important for regulating viral replication. The stem-loop 1 (SL1 sequence in the 5' untranslated region directs HIV-1 genomic RNA dimerization and packaging into the virion. Without SL1, HIV-1 cannot replicate in human T cell lines. The replication restriction phenotype in the SL1 deletion mutant appears to be multifactorial, with defects in viral RNA dimerization and packaging in producer cells as well as in reverse transcription of the viral RNA in infected cells. In this study, we sought to characterize SL1 mutant replication restrictions and provide insights into the underlying mechanisms of compensation in revertants. Results HIV-1 lacking SL1 (NLΔSL1 did not replicate in PM-1 cells until two independent non-synonymous mutations emerged: G913A in the matrix domain (E42K on day 18 postinfection and C1907T in the SP1 domain (P10L on day 11 postinfection. NLΔSL1 revertants carrying either compensatory mutation showed enhanced infectivity in PM-1 cells. The SL1 revertants produced significantly more infectious particles per nanogram of p24 than did NLΔSL1. The SL1 deletion mutant packaged less HIV-1 genomic RNA and more cellular RNA, particularly signal recognition particle RNA, in the virion than the wild-type. NLΔSL1 also packaged 3- to 4-fold more spliced HIV mRNA into the virion, potentially interfering with infectious virus production. In contrast, both revertants encapsidated 2.5- to 5-fold less of these HIV-1 mRNA species. Quantitative RT-PCR analysis of RNA cross-linked with Gag in formaldehyde-fixed cells demonstrated that the compensatory mutations reduced the association between Gag and spliced HIV-1 RNA, thereby effectively preventing these RNAs from being packaged into the virion. The reduction of spliced viral RNA in the virion may have a major role in facilitating infectious virus production, thus restoring the infectivity of NLΔSL1

  4. SHAPE analysis of the FIV Leader RNA reveals a structural switch potentially controlling viral packaging and genome dimerization.

    Science.gov (United States)

    Kenyon, Julia C; Tanner, Sian J; Legiewicz, Michal; Phillip, Pretty S; Rizvi, Tahir A; Le Grice, Stuart F J; Lever, Andrew M L

    2011-08-01

    Feline immunodeficiency virus (FIV) infects many species of cat, and is related to HIV, causing a similar pathology. High-throughput selective 2' hydroxyl acylation analysed by primer extension (SHAPE), a technique that allows structural interrogation at each nucleotide, was used to map the secondary structure of the FIV packaging signal RNA. Previous studies of this RNA showed four conserved stem-loops, extensive long-range interactions (LRIs) and a small, palindromic stem-loop (SL5) within the gag open reading frame (ORF) that may act as a dimerization initiation site (DIS), enabling the virus to package two copies of its genome. Our analyses of wild-type (wt) and mutant RNAs suggest that although the four conserved stem-loops are static structures, the 5' and 3' regions previously shown to form LRI also adopt an alternative, yet similarly conserved conformation, in which the putative DIS is occluded, and which may thus favour translational and splicing functions over encapsidation. SHAPE and in vitro dimerization assays were used to examine SL5 mutants. Dimerization contacts appear to be made between palindromic loop sequences in SL5. As this stem-loop is located within the gag ORF, recognition of a dimeric RNA provides a possible mechanism for the specific packaging of genomic over spliced viral RNAs.

  5. Structure of Hepatitis E Virion-Sized Particle Reveals an RNA-Dependent Viral Assembly Pathway

    Energy Technology Data Exchange (ETDEWEB)

    Xing, L.; Wall, J.; Li, T.-C.; Mayazaki, N.; Simon, M. N.; Moore, M.; Wang, C.-Y.; Takeda, N.; Wakita, T.; Miyamura, T.; Cheng, R. H.

    2010-10-22

    Hepatitis E virus (HEV) induces acute hepatitis in humans with a high fatality rate in pregnant women. There is a need for anti-HEV research to understand the assembly process of HEV native capsid. Here, we produced a large virion-sized and a small T=1 capsid by expressing the HEV capsid protein in insect cells with and without the N-terminal 111 residues, respectively, for comparative structural analysis. The virion-sized capsid demonstrates a T=3 icosahedral lattice and contains RNA fragment in contrast to the RNA-free T=1 capsid. However, both capsids shared common decameric organization. The in vitro assembly further demonstrated that HEV capsid protein had the intrinsic ability to form decameric intermediate. Our data suggest that RNA binding is the extrinsic factor essential for the assembly of HEV native capsids.

  6. Modeling Zika plasma viral dynamics in non-human primates: insights into viral pathogenesis and antiviral strategies

    Energy Technology Data Exchange (ETDEWEB)

    Best, Katharine [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Guedj, Jeremie [Univ. of Paris (France). IAME; Madelain, Vincent [Univ. of Paris (France); de Lamballerie, Xavier [Aix-Marseille Univ. (France); L, So-Yonim [Harvard Univ., Cambridge, MA (United States). Center for Virology and Vaccine Research; Osuna, Christa E [Harvard Univ., Cambridge, MA (United States). Center for Virology and Vaccine Research; Whitney, James [Harvard Univ., Cambridge, MA (United States). Center for Virology and Vaccine Research; Perelson, Alan S. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-10-24

    The recent outbreak of Zika virus (ZIKV) has been associated with fetal abnormalities and neurological complications, prompting global concern. Here we present the first mathematical analysis of the within-host dynamics of plasma ZiKV burden in a non-human primate model, allowing for characterization of the growth and clearance of ZIKV within an individual macaque.

  7. The small delta antigen of hepatitis delta virus is an acetylated protein and acetylation of lysine 72 may influence its cellular localization and viral RNA synthesis

    International Nuclear Information System (INIS)

    Mu, J.-J.; Tsay, Y.-G.; Juan, L.-J.; Fu, T.-F.; Huang, W.-H.; Chen, D.-S.; Chen, P.-J.

    2004-01-01

    Hepatitis delta virus (HDV) is a single-stranded RNA virus that encodes two viral nucleocapsid proteins named small and large form hepatitis delta antigen (S-HDAg and L-HDAg). The S-HDAg is essential for viral RNA replication while the L-HDAg is required for viral assembly. In this study, we demonstrated that HDAg are acetylated proteins. Metabolic labeling with [ 3 H]acetate revealed that both forms of HDAg could be acetylated in vivo. The histone acetyltransferase (HAT) domain of cellular acetyltransferase p300 could acetylate the full-length and the N-terminal 88 amino acids of S-HDAg in vitro. By mass spectrometric analysis of the modified protein, Lys-72 of S-HDAg was identified as one of the acetylation sites. Substitution of Lys-72 to Arg caused the mutant S-HDAg to redistribute from the nucleus to the cytoplasm. The mutant reduced viral RNA accumulation and resulted in the earlier appearance of L-HDAg. These results demonstrated that HDAg is an acetylated protein and mutation of HDAg at Lys-72 modulates HDAg subcellular localization and may participate in viral RNA nucleocytoplasmic shuttling and replication

  8. Leeches as a source of mammalian viral DNA and RNA - a study in medicinal leeches

    DEFF Research Database (Denmark)

    Kampmann, Marie-Louise; Schnell, Ida Bærholm; Jensen, Randi Holm

    2017-01-01

    V]) from nucleic acids extracted from medicinal leeches fed with blood spiked with each virus. All viruses except BHV showed a gradual decline in concentration from day 1 to 50, and all except BHV were detectable in at least half of the samples even after 50 days. BHV exhibited a rapid decline at day 27...... and was undetectable at day 50. Our findings in medicinal leeches indicate that leeches collected in the wild might be an untapped resource for detecting vertebrate viruses and could provide new opportunities to study wildlife viral diseases of rare species in challenging environments, where capturing and handling...

  9. Comparison of miRNA quantitation by Nanostring in serum and plasma samples.

    Directory of Open Access Journals (Sweden)

    Catherine Foye

    Full Text Available Circulating microRNAs that are associated with specific diseases have garnered much attention for use in diagnostic assays. However, detection of disease-associated miRNA can be affected by several factors such as release of contaminating cellular miRNA during sample collection, variations due to amplification of transcript for detection, or controls used for normalization for accurate quantitation. We analyzed circulating miRNA in serum and plasma samples obtained concurrently from 28 patients, using a Nanostring quantitative assay platform. Total RNA concentration ranged from 32-125 μg/ml from serum and 30-220 μg/ml from plasma. Of 798 miRNAs, 371 miRNAs were not detected in either serum or plasma samples. 427 were detected in either serum or plasma but not both, whereas 151 miRNA were detected in both serum and plasma samples. The diversity of miRNA detected was greater in plasma than in serum samples. In serum samples, the number of detected miRNA ranged from 3 to 82 with a median of 17, whereas in plasma samples, the number of miRNA detected ranged from 25 to 221 with a median of 91. Several miRNA such as miR451a, miR 16-5p, miR-223-3p, and mir25-3p were highly abundant and differentially expressed between serum and plasma. The detection of endogenous and exogenous control miRNAs varied in serum and plasma, with higher levels observed in plasma. Gene expression stability identified candidate invariant microRNA that were highly stable across all samples, and could be used for normalization. In conclusion, there are significant differences in both the number of miRNA detected and the amount of miRNA detected between serum and plasma. Normalization using miRNA with constant expression is essential to minimize the impact of technical variations. Given the challenges involved, ideal candidates for blood based biomarkers would be those that are indifferent to type of body fluid, are detectable and can be reliably quantitated.

  10. Phosphate-methylated DNA aimed at HIV-1 RNA loops and integrated DNA inhibits viral infectivity

    NARCIS (Netherlands)

    Buck, H. M.; Koole, L. H.; van Genderen, M. H.; Smit, L.; Geelen, J. L.; Jurriaans, S.; Goudsmit, J.

    1990-01-01

    Phosphate-methylated DNA hybridizes strongly and specifically to natural DNA and RNA. Hybridization to single-stranded and double-stranded DNA leads to site-selective blocking of replication and transcription. Phosphate-methylated DNA was used to interrupt the life cycle of the human

  11. The Ebola Virus VP30-NP Interaction Is a Regulator of Viral RNA Synthesis.

    Directory of Open Access Journals (Sweden)

    Robert N Kirchdoerfer

    2016-10-01

    Full Text Available Filoviruses are capable of causing deadly hemorrhagic fevers. All nonsegmented negative-sense RNA-virus nucleocapsids are composed of a nucleoprotein (NP, a phosphoprotein (VP35 and a polymerase (L. However, the VP30 RNA-synthesis co-factor is unique to the filoviruses. The assembly, structure, and function of the filovirus RNA replication complex remain unclear. Here, we have characterized the interactions of Ebola, Sudan and Marburg virus VP30 with NP using in vitro biochemistry, structural biology and cell-based mini-replicon assays. We have found that the VP30 C-terminal domain interacts with a short peptide in the C-terminal region of NP. Further, we have solved crystal structures of the VP30-NP complex for both Ebola and Marburg viruses. These structures reveal that a conserved, proline-rich NP peptide binds a shallow hydrophobic cleft on the VP30 C-terminal domain. Structure-guided Ebola virus VP30 mutants have altered affinities for the NP peptide. Correlation of these VP30-NP affinities with the activity for each of these mutants in a cell-based mini-replicon assay suggests that the VP30-NP interaction plays both essential and inhibitory roles in Ebola virus RNA synthesis.

  12. The Ebola Virus VP30-NP Interaction Is a Regulator of Viral RNA Synthesis

    Energy Technology Data Exchange (ETDEWEB)

    Kirchdoerfer, Robert N.; Moyer, Crystal L.; Abelson, Dafna M.; Saphire, Erica Ollmann (Scripps)

    2016-10-18

    Filoviruses are capable of causing deadly hemorrhagic fevers. All nonsegmented negative-sense RNA-virus nucleocapsids are composed of a nucleoprotein (NP), a phosphoprotein (VP35) and a polymerase (L). However, the VP30 RNA-synthesis co-factor is unique to the filoviruses. The assembly, structure, and function of the filovirus RNA replication complex remain unclear. Here, we have characterized the interactions of Ebola, Sudan and Marburg virus VP30 with NP using in vitro biochemistry, structural biology and cell-based mini-replicon assays. We have found that the VP30 C-terminal domain interacts with a short peptide in the C-terminal region of NP. Further, we have solved crystal structures of the VP30-NP complex for both Ebola and Marburg viruses. These structures reveal that a conserved, proline-rich NP peptide binds a shallow hydrophobic cleft on the VP30 C-terminal domain. Structure-guided Ebola virus VP30 mutants have altered affinities for the NP peptide. Correlation of these VP30-NP affinities with the activity for each of these mutants in a cell-based mini-replicon assay suggests that the VP30-NP interaction plays both essential and inhibitory roles in Ebola virus RNA synthesis.

  13. Rational design of avian metapneumovirus live attenuated vaccines by inhibiting viral messenger RNA cap methyltransferase

    Science.gov (United States)

    Avian metapneumovirus (aMPV), also known as avian pneumovirus or turkey rhinotracheitis, is a non-segmented negative-sense RNA virus belonging to the family of Paramyxoviridae, the subfamily Pneumovirinae, and the genus Metapneumovirus. aMPV is the causative agent of respiratory tract infection and ...

  14. Inhibition of host protein synthesis by Sindbis virus: correlation with viral RNA replication and release of nuclear proteins to the cytoplasm.

    Science.gov (United States)

    Sanz, Miguel A; García-Moreno, Manuel; Carrasco, Luis

    2015-04-01

    Infection of mammalian cells by Sindbis virus (SINV) profoundly blocks cellular mRNA translation. Experimental evidence points to viral non-structural proteins (nsPs), in particular nsP2, as the mediator of this inhibition. However, individual expression of nsP1, nsP2, nsP3 or nsP1-4 does not block cellular protein synthesis in BHK cells. Trans-complementation of a defective SINV replicon lacking most of the coding region for nsPs by the co-expression of nsP1-4 propitiates viral RNA replication at low levels, and inhibition of cellular translation is not observed. Exit of nuclear proteins including T-cell intracellular antigen and polypyrimidine tract-binding protein is clearly detected in SINV-infected cells, but not upon the expression of nsPs, even when the defective replicon was complemented. Analysis of a SINV variant with a point mutation in nsP2, exhibiting defects in the shut-off of host protein synthesis, indicates that both viral RNA replication and the release of nuclear proteins to the cytoplasm are greatly inhibited. Furthermore, nucleoside analogues that inhibit cellular and viral RNA synthesis impede the blockade of host mRNA translation, in addition to the release of nuclear proteins. Prevention of the shut-off of host mRNA translation by nucleoside analogues is not due to the inhibition of eIF2α phosphorylation, as this prevention is also observed in PKR(-/-) mouse embryonic fibroblasts that do not phosphorylate eIF2α after SINV infection. Collectively, our observations are consistent with the concept that for the inhibition of cellular protein synthesis to occur, viral RNA replication must take place at control levels, leading to the release of nuclear proteins to the cytoplasm. © 2014 John Wiley & Sons Ltd.

  15. Double stranded viral RNA induces inflammation and insulin resistance in skeletal muscle from pregnant women in vitro.

    Science.gov (United States)

    Lappas, Martha

    2015-05-01

    Maternal peripheral insulin resistance and increased inflammation are two features of pregnancies complicated by pre-existing maternal obesity and gestational diabetes mellitus (GDM). There is now increasing evidence that activation of Toll-like receptor (TLR) signalling pathways by viral products may play a role in the pathophysiology of diabetes. Thus, the aim of this study was to assess the effect of the TLR3 ligand and viral dsRNA analogue polyinosinic polycytidilic acid (poly(I:C)) on inflammation and the insulin signalling pathway in skeletal muscle from pregnant women. Human skeletal muscle tissue explants were performed to determine the effect of poly(I:C) on the expression and secretion of markers of inflammation, and the insulin signalling pathway and glucose uptake. Poly(I:C) significantly increased the expression of a number of inflammatory markers in skeletal muscle from pregnant women. Specifically, there was an increase in the expression and/or secretion of the pro-inflammatory cytokines TNF-α, and IL-6 and the pro-inflammatory chemokines IL-8 and MCP-1. These effect of poly(I:C) appear to mediated via a number of signalling molecules including the pro-inflammatory transcription factor NF-κB, and the serine threonine kinases GSK3 and AMPKα. Additionally, poly(I:C) decreased insulin stimulated GLUT-4 expression and glucose uptake in skeletal muscle from pregnant women. The in vitro data presented in this study suggests that viral infection may contribute to the pathophysiology of pregnancies complicated by pre-existing maternal obesity and/or GDM. It should be noted that the in vitro studies cannot be directly used to infer the same outcomes in the intact subject. Copyright © 2015 Elsevier Inc. All rights reserved.

  16. The viral transmembrane superfamily: possible divergence of Arenavirus and Filovirus glycoproteins from a common RNA virus ancestor

    Directory of Open Access Journals (Sweden)

    Buchmeier Michael J

    2001-02-01

    Full Text Available Abstract Background Recent studies of viral entry proteins from influenza, measles, human immunodeficiency virus, type 1 (HIV-1, and Ebola virus have shown, first with molecular modeling, and then X-ray crystallographic or other biophysical studies, that these disparate viruses share a coiled-coil type of entry protein. Results Structural models of the transmembrane glycoproteins (GP-2 of the Arenaviruses, lymphochoriomeningitis virus (LCMV and Lassa fever virus, are presented, based on consistent structural propensities despite variation in the amino acid sequence. The principal features of the model, a hydrophobic amino terminus, and two antiparallel helices separated by a glycosylated, antigenic apex, are common to a number of otherwise disparate families of enveloped RNA viruses. Within the first amphipathic helix, demonstrable by circular dichroism of a peptide fragment, there is a highly conserved heptad repeat pattern proposed to mediate multimerization by coiled-coil interactions. The amino terminal 18 amino acids are 28% identical and 50% highly similar to the corresponding region of Ebola, a member of the Filovirus family. Within the second, charged helix just prior to membrane insertion there is also high similarity over the central 18 amino acids in corresponding regions of Lassa and Ebola, which may be further related to the similar region of HIV-1 defining a potent antiviral peptide analogue. Conclusions These findings indicate a common pattern of structure and function among viral transmembrane fusion proteins from a number of virus families. Such a pattern may define a viral transmembrane superfamily that evolved from a common precursor eons ago.

  17. MicroRNA-Related Polymorphisms in Infectious Diseases—Tiny Changes With a Huge Impact on Viral Infections and Potential Clinical Applications

    Directory of Open Access Journals (Sweden)

    Joel Henrique Ellwanger

    2018-06-01

    Full Text Available MicroRNAs (miRNAs are single-stranded sequences of non-coding RNA with approximately 22 nucleotides that act posttranscriptionally on gene expression. miRNAs are important gene regulators in physiological contexts, but they also impact the pathogenesis of various diseases. The role of miRNAs in viral infections has been explored by different authors in both population-based as well as in functional studies. However, the effect of miRNA polymorphisms on the susceptibility to viral infections and on the clinical course of these diseases is still an emerging topic. Thus, this review will compile and organize the findings described in studies that evaluated the effects of genetic variations on miRNA genes and on their binding sites, in the context of human viral diseases. In addition to discussing the basic aspects of miRNAs biology, we will cover the studies that investigated miRNA polymorphisms in infections caused by hepatitis B virus, hepatitis C virus, human immunodeficiency virus, Epstein–Barr virus, and human papillomavirus. Finally, emerging topics concerning the importance of miRNA genetic variants will be presented, focusing on the context of viral infectious diseases.

  18. A novel duplex real-time reverse transcriptase-polymerase chain reaction assay for the detection of hepatitis C viral RNA with armored RNA as internal control

    Directory of Open Access Journals (Sweden)

    Meng Shuang

    2010-06-01

    Full Text Available Abstract Background The hepatitis C virus (HCV genome is extremely heterogeneous. Several HCV infections can not be detected using currently available commercial assays, probably because of mismatches between the template and primers/probes. By aligning the HCV sequences, we developed a duplex real-time reverse transcriptase-polymerase chain reaction (RT-PCR assay using 2 sets of primers/probes and a specific armored RNA as internal control. The 2 detection probes were labelled with the same fluorophore, namely, 6-carboxyfluorescein (FAM, at the 5' end; these probes could mutually combine, improving the power of the test. Results The limit of detection of the duplex primer/probe assay was 38.99 IU/ml. The sensitivity of the assay improved significantly, while the specificity was not affected. All HCV genotypes in the HCV RNA Genotype Panel for Nucleic Acid Amplification Techniques could be detected. In the testing of 109 serum samples, the performance of the duplex real-time RT-PCR assay was identical to that of the COBAS AmpliPrep (CAP/COBAS TaqMan (CTM assay and superior to 2 commercial HCV assay kits. Conclusions The duplex real-time RT-PCR assay is an efficient and effective viral assay. It is comparable with the CAP/CTM assay with regard to the power of the test and is appropriate for blood-donor screening and laboratory diagnosis of HCV infection.

  19. Prevalence of hepatitis A viral RNA and antibodies among Chinese blood donors.

    Science.gov (United States)

    Sun, P; Su, N; Lin, F Z; Ma, L; Wang, H J; Rong, X; Dai, Y D; Li, J; Jian, Z W; Tang, L H; Xiao, W; Li, C Q

    2015-12-09

    Like other developing countries, China was reported to have a relatively high seroprevalence of anti-hepatitis A antibodies (anti-HAV). However, no studies have evaluated the prevalence of anti-HAV and HAV RNA among voluntary blood donors with or without elevated serum alanine transaminase (ALT) levels. Anti-HAV antibodies were detected using an enzyme-linked immunosorbent assay, and reverse transcription quantitative polymerase chain reaction was carried out for detection of HAV RNA. In the current study, we analyzed a total of 450 serum samples with elevated ALT levels (≥40 U/L) and 278 serum samples with non-elevated ALT levels. Seroprevalence rates of anti-HAV were 51.6% in donors with elevated ALT and 41.4% in donors with non-elevated ALT; however, none of the samples was positive for HAV RNA. The results of our study showed lower seroprevalence rates of anti-HAV in blood donors (irrespective of ALT levels) than those in published data on Chinese populations. Although donors with elevated ALT had statistically higher prevalence rates of anti- HAV than did those with non-elevated ALT, none of the serum samples had detectable levels of the active virus. In conclusion, our results demonstrate that the transmission of hepatitis A by blood transfusion will occur rarely.

  20. The internal initiation of translation in bovine viral diarrhea virus RNA depends on the presence of an RNA pseudoknot upstream of the initiation codon

    Directory of Open Access Journals (Sweden)

    Moes Lorin

    2007-11-01

    Full Text Available Abstract Background Bovine viral diarrhea virus (BVDV is the prototype representative of the pestivirus genus in the Flaviviridae family. It has been shown that the initiation of translation of BVDV RNA occurs by an internal ribosome entry mechanism mediated by the 5' untranslated region of the viral RNA 1. The 5' and 3' boundaries of the IRES of the cytopathic BVDV NADL have been mapped and it has been suggested that the IRES extends into the coding of the BVDV polyprotein 2. A putative pseudoknot structure has been recognized in the BVDV 5'UTR in close proximity to the AUG start codon. A pseudoknot structure is characteristic for flavivirus IRESes and in the case of the closely related classical swine fever virus (CSFV and the more distantly related Hepatitis C virus (HCV pseudoknot function in translation has been demonstrated. Results To characterize the BVDV IRESes in detail, we studied the BVDV translational initiation by transfection of dicistronic expression plasmids into mammalian cells. A region coding for the amino terminus of the BVDV SD-1 polyprotein contributes considerably to efficient initiation of translation. The translation efficiency mediated by the IRES of BVDV strains NADL and SD-1 approximates the poliovirus type I IRES directed translation in BHK cells. Compared to the poliovirus IRES increased expression levels are mediated by the BVDV IRES of strain SD-1 in murine cell lines, while lower levels are observed in human cell lines. Site directed mutagenesis revealed that a RNA pseudoknot upstream of the initiator AUG is an important structural element for IRES function. Mutants with impaired ability to base pair in stem I or II lost their translational activity. In mutants with repaired base pairing either in stem 1 or in stem 2 full translational activity was restored. Thus, the BVDV IRES translation is dependent on the pseudoknot integrity. These features of the pestivirus IRES are reminiscent of those of the classical

  1. The internal initiation of translation in bovine viral diarrhea virus RNA depends on the presence of an RNA pseudoknot upstream of the initiation codon.

    Science.gov (United States)

    Moes, Lorin; Wirth, Manfred

    2007-11-22

    Bovine viral diarrhea virus (BVDV) is the prototype representative of the pestivirus genus in the Flaviviridae family. It has been shown that the initiation of translation of BVDV RNA occurs by an internal ribosome entry mechanism mediated by the 5' untranslated region of the viral RNA 1. The 5' and 3' boundaries of the IRES of the cytopathic BVDV NADL have been mapped and it has been suggested that the IRES extends into the coding of the BVDV polyprotein 2. A putative pseudoknot structure has been recognized in the BVDV 5'UTR in close proximity to the AUG start codon. A pseudoknot structure is characteristic for flavivirus IRESes and in the case of the closely related classical swine fever virus (CSFV) and the more distantly related Hepatitis C virus (HCV) pseudoknot function in translation has been demonstrated. To characterize the BVDV IRESes in detail, we studied the BVDV translational initiation by transfection of dicistronic expression plasmids into mammalian cells. A region coding for the amino terminus of the BVDV SD-1 polyprotein contributes considerably to efficient initiation of translation. The translation efficiency mediated by the IRES of BVDV strains NADL and SD-1 approximates the poliovirus type I IRES directed translation in BHK cells. Compared to the poliovirus IRES increased expression levels are mediated by the BVDV IRES of strain SD-1 in murine cell lines, while lower levels are observed in human cell lines. Site directed mutagenesis revealed that a RNA pseudoknot upstream of the initiator AUG is an important structural element for IRES function. Mutants with impaired ability to base pair in stem I or II lost their translational activity. In mutants with repaired base pairing either in stem 1 or in stem 2 full translational activity was restored. Thus, the BVDV IRES translation is dependent on the pseudoknot integrity. These features of the pestivirus IRES are reminiscent of those of the classical swine fever virus, a pestivirus, and the

  2. Detection of chikungunya viral RNA in mosquito bodies on cationic (Q) paper based on innovations in synthetic biology.

    Science.gov (United States)

    Glushakova, Lyudmyla G; Alto, Barry W; Kim, Myong Sang; Bradley, Andrea; Yaren, Ozlem; Benner, Steven A

    2017-08-01

    Chikungunya virus (CHIKV) represents a growing and global concern for public health that needs inexpensive and convenient methods to collect mosquitoes as potential carriers so that they can be preserved, stored and transported for later and/or remote analysis. Reported here is a cellulose-based paper, derivatized with quaternary ammonium groups ("Q-paper") that meets these needs. In a series of tests, infected mosquito bodies were squashed directly on Q-paper. Aqueous ammonia was then added on the mosquito bodies to release viral RNA that adsorbed on the cationic surface via electrostatic interactions. The samples were then stored (frozen) or transported. For analysis, the CHIKV nucleic acids were eluted from the Q-paper and PCR amplified in a workflow, previously developed, that also exploited two nucleic acid innovations, ("artificially expanded genetic information systems", AEGIS, and "self-avoiding molecular recognition systems", SAMRS). The amplicons were then analyzed by a Luminex hybridization assay. This procedure detected CHIKV RNA, if present, in each infected mosquito sample, but not in non-infected counterparts or ddH 2 O samples washes, with testing one week or ten months after sample collection. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. Dynamic changes in HCV RNA levels and viral quasispecies in a patient with chronic hepatitis C after telaprevir-based treatment

    NARCIS (Netherlands)

    de Bruijne, Joep; Sullivan, James C.; Kieffer, Tara L.; Botfield, Martyn; Shames, Ben; Schinkel, Janke; Molenkamp, Richard; Weegink, Christine; Reesink, Henk

    2012-01-01

    Background: Telaprevir is a selective inhibitor of the hepatitis C virus NS3 center dot 4A serine protease. Treatment with telaprevir resulted in a rapid HCV-RNA decline in chronic hepatitis C genotype 1 patients. Objectives: To report the clinical and viral course of a patient treated with

  4. Effects of mutations in the VP2/VP4 cleavage site of Swine vesicular disease virus on RNA encapsidation and viral infectivity

    NARCIS (Netherlands)

    Rebel, J.M.J.; Leendertse, C.H.; Dekker, A.; Moormann, R.J.M.

    2003-01-01

    We studied VP0 cleavage of Swine vesicular disease virus (SVDV), a member of the Picornaviridae using a full-length cDNA copy of the Dutch SVDV isolate. The influences of mutations, introduced at the cleavage site of SVDV, on VP0 cleavage, RNA encapsidation and viral infection were studied. Double

  5. Amino acid substitutions affecting aspartic acid 605 and valine 606 decrease the interaction strength between the influenza virus RNA polymerase PB2 '627' domain and the viral nucleoprotein.

    Science.gov (United States)

    Hsia, Ho-Pan; Yang, Yin-Hua; Szeto, Wun-Chung; Nilsson, Benjamin E; Lo, Chun-Yeung; Ng, Andy Ka-Leung; Fodor, Ervin; Shaw, Pang-Chui

    2018-01-01

    The influenza virus RNA genome is transcribed and replicated in the context of the viral ribonucleoprotein (vRNP) complex by the viral RNA polymerase. The nucleoprotein (NP) is the structural component of the vRNP providing a scaffold for the viral RNA. In the vRNP as well as during transcription and replication the viral polymerase interacts with NP but it is unclear which parts of the polymerase and NP mediate these interactions. Previously the C-terminal '627' domain (amino acids 538-693) of PB2 was shown to interact with NP. Here we report that a fragment encompassing amino acids 146-185 of NP is sufficient to mediate this interaction. Using NMR chemical shift perturbation assays we show that amino acid region 601 to 607 of the PB2 '627' domain interacts with this fragment of NP. Substitutions of these PB2 amino acids resulted in diminished RNP activity and surface plasmon resonance assays showed that amino acids D605 was essential for the interaction with NP and V606 may also play a partial role in the interaction. Collectively these results reveal a possible interaction surface between NP and the PB2 subunit of the RNA polymerase complex.

  6. Identification and characterization of viral defective RNA genomes in influenza B virus.

    Science.gov (United States)

    Sheng, Zizhang; Liu, Runxia; Yu, Jieshi; Ran, Zhiguang; Newkirk, Simon J; An, Wenfeng; Li, Feng; Wang, Dan

    2018-04-01

    Influenza B virus (FLUBV) is an important pathogen that infects humans and causes seasonal influenza epidemics. To date, little is known about defective genomes of FLUBV and their roles in viral replication. In this study, by using a next-generation sequencing approach, we analyzed total mRNAs extracted from A549 cells infected with B/Brisbane/60/2008 virus (Victoria lineage), and identified four defective FLUBV genomes with two (PB1∆A and PB1∆B) from the polymerase basic subunit 1 (PB1) segment and the other two (M∆A and M∆B) from the matrix (M) protein-encoding segment. These defective genomes contained significant deletions in the central regions with each having the potential for encoding a novel polypeptide. Significantly, each of the discovered defective RNAs can potently inhibit the replication of B/Yamanashi/166/98 (Yamagata lineage). Furthermore, PB1∆A was able to interfere modestly with influenza A virus (FLUAV) replication. In summary, our study provides important initial insights into FLUBV defective-interfering genomes, which can be further explored to achieve better understanding of the replication, pathogenesis and evolution of FLUBV.

  7. Comparison of sampling methods to measure HIV RNA viral load in female genital tract secretions.

    Science.gov (United States)

    Jaumdally, Shameem Z; Jones, Heidi E; Hoover, Donald R; Gamieldien, Hoyam; Kriek, Jean-Mari; Langwenya, Nontokozo; Myer, Landon; Passmore, Jo-Ann S; Todd, Catherine S

    2017-03-01

    How does menstrual cup (MC) compare to other genital sampling methods for HIV RNA recovery? We compared HIV RNA levels between MC, endocervical swab (ECS), and ECS-enriched cervicovaginal lavage (eCVL) specimens in 51 HIV-positive, antiretroviral therapy-naive women at enrollment, 3 and 6 months, with order rotated by visit. Paired comparisons were analyzed with McNemar's exact tests, signed-rank tests, and an extension of Somer's D for pooled analyses across visits. MC specimens had the highest proportion of quantifiable HIV VL at enrollment and month 3, but more MC specimens (n=12.8%) were insufficient for testing, compared with ECS (2%, P=0.006) and eCVL (0%, P<0.001). Among sufficient specimens, median VL was significantly higher for MC (2.62 log 10 copies/mL) compared to ECS (1.30 log 10 copies/mL, P<0.001) and eCVL (1.60 log 10 copies/mL, P<0.001) across visits. MC may be more sensitive than eCVL and CVS, provided insufficient specimens are reduced. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  8. Patterns of oligonucleotide sequences in viral and host cell RNA identify mediators of the host innate immune system.

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    Benjamin D Greenbaum

    Full Text Available The innate immune response provides a first line of defense against pathogens by targeting generic differential features that are present in foreign organisms but not in the host. These innate responses generate selection forces acting both in pathogens and hosts that further determine their co-evolution. Here we analyze the nucleic acid sequence fingerprints of these selection forces acting in parallel on both host innate immune genes and ssRNA viral genomes. We do this by identifying dinucleotide biases in the coding regions of innate immune response genes in plasmacytoid dendritic cells, and then use this signal to identify other significant host innate immune genes. The persistence of these biases in the orthologous groups of genes in humans and chickens is also examined. We then compare the significant motifs in highly expressed genes of the innate immune system to those in ssRNA viruses and study the evolution of these motifs in the H1N1 influenza genome. We argue that the significant under-represented motif pattern of CpG in an AU context--which is found in both the ssRNA viruses and innate genes, and has decreased throughout the history of H1N1 influenza replication in humans--is immunostimulatory and has been selected against during the co-evolution of viruses and host innate immune genes. This shows how differences in host immune biology can drive the evolution of viruses that jump into species with different immune priorities than the original host.

  9. Cellular toxicity following application of adeno-associated viral vector-mediated RNA interference in the nervous system

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    Verhaagen Joost

    2010-02-01

    Full Text Available Abstract Background After a spinal cord lesion, axon regeneration is inhibited by the presence of a diversity of inhibitory molecules in the lesion environment. At and around the lesion site myelin-associated inhibitors, chondroitin sulfate proteoglycans (CSPGs and several axon guidance molecules, including all members of the secreted (class 3 Semaphorins, are expressed. Interfering with multiple inhibitory signals could potentially enhance the previously reported beneficial effects of blocking single molecules. RNA interference (RNAi is a tool that can be used to simultaneously silence expression of multiple genes. In this study we aimed to employ adeno-associated virus (AAV mediated expression of short hairpin RNAs (shRNAs to target all Semaphorin class 3 signaling by knocking down its receptors, Neuropilin 1 (Npn-1 and Neuropilin 2 (Npn-2. Results We have successfully generated shRNAs that knock down Npn-1 and Npn-2 in a neuronal cell line. We detected substantial knockdown of Npn-2 mRNA when AAV5 viral vector particles expressing Npn-2 specific shRNAs were injected in dorsal root ganglia (DRG of the rat. Unexpectedly however, AAV1-mediated expression of Npn-2 shRNAs and a control shRNA in the red nucleus resulted in an adverse tissue response and neuronal degeneration. The observed toxicity was dose dependent and was not seen with control GFP expressing AAV vectors, implicating the shRNAs as the causative toxic agents. Conclusions RNAi is a powerful tool to knock down Semaphorin receptor expression in neuronal cells in vitro and in vivo. However, when shRNAs are expressed at high levels in CNS neurons, they trigger an adverse tissue response leading to neuronal degradation.

  10. Lipid droplet-binding protein TIP47 regulates hepatitis C Virus RNA replication through interaction with the viral NS5A protein.

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    Dorothee A Vogt

    Full Text Available The nonstructural protein NS5A has emerged as a new drug target in antiviral therapies for Hepatitis C Virus (HCV infection. NS5A is critically involved in viral RNA replication that takes place at newly formed membranes within the endoplasmic reticulum (membranous web and assists viral assembly in the close vicinity of lipid droplets (LDs. To identify host proteins that interact with NS5A, we performed a yeast two-hybrid screen with the N-terminus of NS5A (amino acids 1-31, a well-studied α-helical domain important for the membrane tethering of NS5A. Our studies identified the LD-associated host protein, Tail-Interacting Protein 47 (TIP47 as a novel NS5A interaction partner. Coimmunoprecipitation experiments in Huh7 hepatoma cells confirmed the interaction of TIP47 with full-length NS5A. shRNA-mediated knockdown of TIP47 caused a more than 10-fold decrease in the propagation of full-length infectious HCV in Huh7.5 hepatoma cells. A similar reduction was observed when TIP47 was knocked down in cells harboring an autonomously replicating HCV RNA (subgenomic replicon, indicating that TIP47 is required for efficient HCV RNA replication. A single point mutation (W9A in NS5A that disrupts the interaction with TIP47 but preserves proper subcellular localization severely decreased HCV RNA replication. In biochemical membrane flotation assays, TIP47 cofractionated with HCV NS3, NS5A, NS5B proteins, and viral RNA, and together with nonstructural viral proteins was uniquely distributed to lower-density LD-rich membrane fractions in cells actively replicating HCV RNA. Collectively, our data support a model where TIP47--via its interaction with NS5A--serves as a novel cofactor for HCV infection possibly by integrating LD membranes into the membranous web.

  11. Small RNA Profiling in Dengue Virus 2-Infected Aedes Mosquito Cells Reveals Viral piRNAs and Novel Host miRNAs.

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    Miesen, Pascal; Ivens, Alasdair; Buck, Amy H; van Rij, Ronald P

    2016-02-01

    In Aedes mosquitoes, infections with arthropod-borne viruses (arboviruses) trigger or modulate the expression of various classes of viral and host-derived small RNAs, including small interfering RNAs (siRNAs), PIWI interacting RNAs (piRNAs), and microRNAs (miRNAs). Viral siRNAs are at the core of the antiviral RNA interference machinery, one of the key pathways that limit virus replication in invertebrates. Besides siRNAs, Aedes mosquitoes and cells derived from these insects produce arbovirus-derived piRNAs, the best studied examples being viruses from the Togaviridae or Bunyaviridae families. Host miRNAs modulate the expression of a large number of genes and their levels may change in response to viral infections. In addition, some viruses, mostly with a DNA genome, express their own miRNAs to regulate host and viral gene expression. Here, we perform a comprehensive analysis of both viral and host-derived small RNAs in Aedes aegypti Aag2 cells infected with dengue virus 2 (DENV), a member of the Flaviviridae family. Aag2 cells are competent in producing all three types of small RNAs and provide a powerful tool to explore the crosstalk between arboviral infection and the distinct RNA silencing pathways. Interestingly, besides the well-characterized DENV-derived siRNAs, a specific population of viral piRNAs was identified in infected Aag2 cells. Knockdown of Piwi5, Ago3 and, to a lesser extent, Piwi6 results in reduction of vpiRNA levels, providing the first genetic evidence that Aedes PIWI proteins produce DENV-derived small RNAs. In contrast, we do not find convincing evidence for the production of virus-derived miRNAs. Neither do we find that host miRNA expression is strongly changed upon DENV2 infection. Finally, our deep-sequencing analyses detect 30 novel Aedes miRNAs, complementing the repertoire of regulatory small RNAs in this important vector species.

  12. Down-regulation of viral replication by adenoviral-mediated expression of siRNA against cellular cofactors for hepatitis C virus

    International Nuclear Information System (INIS)

    Zhang Jing; Yamada, Osamu; Sakamoto, Takashi; Yoshida, Hiroshi; Iwai, Takahiro; Matsushita, Yoshihisa; Shimamura, Hideo; Araki, Hiromasa; Shimotohno, Kunitada

    2004-01-01

    Small interfering RNA (siRNA) is currently being evaluated not only as a powerful tool for functional genomics, but also as a potentially promising therapeutic agent for cancer and infectious diseases. Inhibitory effect of siRNA on viral replication has been demonstrated in multiple pathogenic viruses. However, because of the high sequence specificity of siRNA-mediated RNA degradation, antiviral efficacy of siRNA directed to viral genome will be largely limited by emergence of escape variants resistant to siRNA due to high mutation rates of virus, especially RNA viruses such as poliovirus and hepatitis C virus (HCV). To investigate the therapeutic feasibility of siRNAs specific for the putative cellular cofactors for HCV, we constructed adenovirus vectors expressing siRNAs against La, polypyrimidine tract-binding protein (PTB), subunit gamma of human eukaryotic initiation factors 2B (eIF2Bγ), and human VAMP-associated protein of 33 kDa (hVAP-33). Adenoviral-mediated expression of siRNAs markedly diminished expression of the endogenous genes, and silencing of La, PTB, and hVAP-33 by siRNAs substantially blocked HCV replication in Huh-7 cells. Thus, our studies demonstrate the feasibility and potential of adenoviral-delivered siRNAs specific for cellular cofactors in combating HCV infection, which can be used either alone or in combination with siRNA against viral genome to prevent the escape of mutant variants and provide additive or synergistic anti-HCV effects

  13. Structure and functional analysis of the RNA- and viral phosphoprotein-binding domain of respiratory syncytial virus M2-1 protein.

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    Marie-Lise Blondot

    Full Text Available Respiratory syncytial virus (RSV protein M2-1 functions as an essential transcriptional cofactor of the viral RNA-dependent RNA polymerase (RdRp complex by increasing polymerase processivity. M2-1 is a modular RNA binding protein that also interacts with the viral phosphoprotein P, another component of the RdRp complex. These binding properties are related to the core region of M2-1 encompassing residues S58 to K177. Here we report the NMR structure of the RSV M2-1(58-177 core domain, which is structurally homologous to the C-terminal domain of Ebola virus VP30, a transcription co-factor sharing functional similarity with M2-1. The partial overlap of RNA and P interaction surfaces on M2-1(58-177, as determined by NMR, rationalizes the previously observed competitive behavior of RNA versus P. Using site-directed mutagenesis, we identified eight residues located on these surfaces that are critical for an efficient transcription activity of the RdRp complex. Single mutations of these residues disrupted specifically either P or RNA binding to M2-1 in vitro. M2-1 recruitment to cytoplasmic inclusion bodies, which are regarded as sites of viral RNA synthesis, was impaired by mutations affecting only binding to P, but not to RNA, suggesting that M2-1 is associated to the holonucleocapsid by interacting with P. These results reveal that RNA and P binding to M2-1 can be uncoupled and that both are critical for the transcriptional antitermination function of M2-1.

  14. Enrichment of Phosphatidylethanolamine in Viral Replication Compartments via Co-opting the Endosomal Rab5 Small GTPase by a Positive-Strand RNA Virus.

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    Kai Xu

    2016-10-01

    Full Text Available Positive-strand RNA viruses build extensive membranous replication compartments to support replication and protect the virus from antiviral responses by the host. These viruses require host factors and various lipids to form viral replication complexes (VRCs. The VRCs built by Tomato bushy stunt virus (TBSV are enriched with phosphatidylethanolamine (PE through a previously unknown pathway. To unravel the mechanism of PE enrichment within the TBSV replication compartment, in this paper, the authors demonstrate that TBSV co-opts the guanosine triphosphate (GTP-bound active form of the endosomal Rab5 small GTPase via direct interaction with the viral replication protein. Deletion of Rab5 orthologs in a yeast model host or expression of dominant negative mutants of plant Rab5 greatly decreases TBSV replication and prevents the redistribution of PE to the sites of viral replication. We also show that enrichment of PE in the viral replication compartment is assisted by actin filaments. Interestingly, the closely related Carnation Italian ringspot virus, which replicates on the boundary membrane of mitochondria, uses a similar strategy to the peroxisomal TBSV to hijack the Rab5-positive endosomes into the viral replication compartments. Altogether, usurping the GTP-Rab5-positive endosomes allows TBSV to build a PE-enriched viral replication compartment, which is needed to support peak-level replication. Thus, the Rab family of small GTPases includes critical host factors assisting VRC assembly and genesis of the viral replication compartment.

  15. Downregulation of viral RNA translation by hepatitis C virus non-structural protein NS5A requires the poly(U/UC) sequence in the 3' UTR.

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    Hoffman, Brett; Li, Zhubing; Liu, Qiang

    2015-08-01

    Hepatitis C virus (HCV) non-structural protein 5A (NS5A) is essential for viral replication; however, its effect on HCV RNA translation remains controversial partially due to the use of reporters lacking the 3' UTR, where NS5A binds to the poly(U/UC) sequence. We investigated the role of NS5A in HCV translation using a monocistronic RNA containing a Renilla luciferase gene flanked by the HCV UTRs. We found that NS5A downregulated viral RNA translation in a dose-dependent manner. This downregulation required both the 5' and 3' UTRs of HCV because substitution of either sequence with the 5' and 3' UTRs of enterovirus 71 or a cap structure at the 5' end eliminated the effects of NS5A on translation. Translation of the HCV genomic RNA was also downregulated by NS5A. The inhibition of HCV translation by NS5A required the poly(U/UC) sequence in the 3' UTR as NS5A did not affect translation when it was deleted. In addition, we showed that, whilst the amphipathic α-helix of NS5A has no effect on viral translation, the three domains of NS5A can inhibit translation independently, also dependent on the presence of the poly(U/UC) sequence in the 3' UTR. These results suggested that NS5A downregulated HCV RNA translation through a mechanism involving the poly(U/UC) sequence in the 3' UTR.

  16. Y-box-binding protein 1 interacts with hepatitis C virus NS3/4A and influences the equilibrium between viral RNA replication and infectious particle production.

    Science.gov (United States)

    Chatel-Chaix, Laurent; Melançon, Pierre; Racine, Marie-Ève; Baril, Martin; Lamarre, Daniel

    2011-11-01

    The hepatitis C virus (HCV) NS3/4A protein has several essential roles in the virus life cycle, most probably through dynamic interactions with host factors. To discover cellular cofactors that are co-opted by HCV for its replication, we elucidated the NS3/4A interactome using mass spectrometry and identified Y-box-binding protein 1 (YB-1) as an interacting partner of NS3/4A protein and HCV genomic RNA. Importantly, silencing YB-1 expression decreased viral RNA replication and severely impaired the propagation of the infectious HCV molecular clone JFH-1. Immunofluorescence studies further revealed a drastic HCV-dependent redistribution of YB-1 to the surface of the lipid droplets, an important organelle for HCV assembly. Core and NS3 protein-dependent polyprotein maturation were shown to be required for YB-1 relocalization. Unexpectedly, YB-1 knockdown cells showed the increased production of viral infectious particles while HCV RNA replication was impaired. Our data support that HCV hijacks YB-1-containing ribonucleoparticles and that YB-1-NS3/4A-HCV RNA complexes regulate the equilibrium between HCV RNA replication and viral particle production.

  17. Excision of a viral reprogramming cassette by delivery of synthetic Cre mRNA

    Science.gov (United States)

    Loh, Yuin-Han; Yang, Jimmy Chen; De Los Angeles, Alejandro; Guo, Chunguang; Cherry, Anne; Rossi, Derrick J.; Park, In-Hyun; Daley, George Q.

    2012-01-01

    The generation of patient-specific induced pluripotent stem (iPS) cells provides an invaluable resource for cell therapy, in vitro modeling of human disease, and drug screening. To date, most human iPS cells have been generated with integrating retro- and lenti-viruses and are limited in their potential utility because residual transgene expression may alter their differentiation potential or induce malignant transformation. Alternatively, transgene-free methods using adenovirus and protein transduction are limited by low efficiency. This report describes a protocol for the generation of transgene-free human induced pluripotent stem cells using retroviral transfection of a single vector, which includes the coding sequences of human OCT4, SOX2, KLF4, and cMYC linked with picornaviral 2A plasmids. Moreover, after reprogramming has been achieved, this cassette can be removed using mRNA transfection of Cre recombinase. The method described herein to excise reprogramming factors with ease and efficiency facilitates the experimental generation and use of transgene-free human iPS cells. PMID:22605648

  18. Screening of Active Lyssavirus Infection in Wild Bat Populations by Viral RNA Detection on Oropharyngeal Swabs

    Science.gov (United States)

    Echevarría, Juan E.; Avellón, Ana; Juste, Javier; Vera, Manuel; Ibáñez, Carlos

    2001-01-01

    Brain analysis cannot be used for the investigation of active lyssavirus infection in healthy bats because most bat species are protected by conservation directives. Consequently, serology remains the only tool for performing virological studies on natural bat populations; however, the presence of antibodies merely reflects past exposure to the virus and is not a valid marker of active infection. This work describes a new nested reverse transcription (RT)-PCR technique specifically designed for the detection of the European bat virus 1 on oropharyngeal swabs obtained from bats but also able to amplify RNA from the remaining rabies-related lyssaviruses in brain samples. The technique was successfully used for surveillance of a serotine bat (Eptesicus serotinus) colony involved in a case of human exposure, in which 15 out of 71 oropharyngeal swabs were positive. Lyssavirus infection was detected on 13 oropharyngeal swabs but in only 5 brains out of the 34 animals from which simultaneous brain and oropharyngeal samples had been taken. The lyssavirus involved could be rapidly identified by automatic sequencing of the RT-PCR products obtained from 14 brains and three bat oropharyngeal swabs. In conclusion, RT-PCR using oropharyngeal swabs will permit screening of wild bat populations for active lyssavirus infection, for research or epidemiological purposes, in line not only with conservation policies but also in a more efficient manner than classical detection techniques used on the brain. PMID:11574590

  19. Short communication: identification of a novel HIV type 1 subtype H/J recombinant in Canada with discordant HIV viral load (RNA) values in three different commercial assays.

    Science.gov (United States)

    Kim, John E; Beckthold, Brenda; Chen, Zhaoxia; Mihowich, Jennifer; Malloch, Laurie; Gill, Michael John

    2007-11-01

    The presence of HIV-1 non-B subtypes is increasing worldwide. This poses challenges to commercial diagnostic and viral load (RNA) monitoring tests that are predominantly based on HIV-1 subtype B strains. Based on phylogenetic analysis of the gag, pol, and env gene regions, we describe the first HIV-1 H/J recombinant in Canada that presented divergent viral load values. DNA sequence analysis of the gag gene region further revealed that genetic diversity between this H/J recombinant and the primers and probes used in the bio-Merieux Nuclisens HIV-1 QT (Nuclisens) and Roche Amplicor Monitor HIV-1, v1.5 (Monitor) viral RNA assays can erroneously lead to undetectable viral load values. This observation appears to be more problematic in the Nuclisens assay. In light of increasing genetic diversity in HIV worldwide we recommend that DNA sequencing of HIV, especially in the gag gene region targeted by primers and probes used in molecular diagnostic and viral load tests, be incorporated into clinical monitoring practices.

  20. Cigarette smoking substantially alters plasma microRNA profiles in healthy subjects

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    Takahashi, Kei; Yokota, Shin-ichi; Tatsumi, Naoyuki; Fukami, Tatsuki; Yokoi, Tsuyoshi; Nakajima, Miki, E-mail: nmiki@p.kanazawa-u.ac.jp

    2013-10-01

    Circulating microRNAs (miRNAs) are receiving attention as potential biomarkers of various diseases, including cancers, chronic obstructive pulmonary disease, and cardiovascular disease. However, it is unknown whether the levels of circulating miRNAs in a healthy subject might vary with external factors in daily life. In this study, we investigated whether cigarette smoking, a habit that has spread throughout the world and is a risk factor for various diseases, affects plasma miRNA profiles. We determined the profiles of 11 smokers and 7 non-smokers by TaqMan MicroRNA array analysis. A larger number of miRNAs were detected in smokers than in non-smokers, and the plasma levels of two-thirds of the detected miRNAs (43 miRNAs) were significantly higher in smokers than in non-smokers. A principal component analysis of the plasma miRNA profiles clearly separated smokers and non-smokers. Twenty-four of the miRNAs were previously reported to be potential biomarkers of disease, suggesting the possibility that smoking status might interfere with the diagnosis of disease. Interestingly, we found that quitting smoking altered the plasma miRNA profiles to resemble those of non-smokers. These results suggested that the differences in the plasma miRNA profiles between smokers and non-smokers could be attributed to cigarette smoking. In addition, we found that an acute exposure of ex-smokers to cigarette smoke (smoking one cigarette) did not cause a dramatic change in the plasma miRNA profile. In conclusion, we found that repeated cigarette smoking substantially alters the plasma miRNA profile, interfering with the diagnosis of disease or signaling potential smoking-related diseases. - Highlights: • Plasma miRNA profiles were unambiguously different between smokers and non-smokers. • Smoking status might interfere with the diagnosis of disease using plasma miRNAs. • Changes of plasma miRNA profiles may be a signal of smoking-related diseases.

  1. Cigarette smoking substantially alters plasma microRNA profiles in healthy subjects

    International Nuclear Information System (INIS)

    Takahashi, Kei; Yokota, Shin-ichi; Tatsumi, Naoyuki; Fukami, Tatsuki; Yokoi, Tsuyoshi; Nakajima, Miki

    2013-01-01

    Circulating microRNAs (miRNAs) are receiving attention as potential biomarkers of various diseases, including cancers, chronic obstructive pulmonary disease, and cardiovascular disease. However, it is unknown whether the levels of circulating miRNAs in a healthy subject might vary with external factors in daily life. In this study, we investigated whether cigarette smoking, a habit that has spread throughout the world and is a risk factor for various diseases, affects plasma miRNA profiles. We determined the profiles of 11 smokers and 7 non-smokers by TaqMan MicroRNA array analysis. A larger number of miRNAs were detected in smokers than in non-smokers, and the plasma levels of two-thirds of the detected miRNAs (43 miRNAs) were significantly higher in smokers than in non-smokers. A principal component analysis of the plasma miRNA profiles clearly separated smokers and non-smokers. Twenty-four of the miRNAs were previously reported to be potential biomarkers of disease, suggesting the possibility that smoking status might interfere with the diagnosis of disease. Interestingly, we found that quitting smoking altered the plasma miRNA profiles to resemble those of non-smokers. These results suggested that the differences in the plasma miRNA profiles between smokers and non-smokers could be attributed to cigarette smoking. In addition, we found that an acute exposure of ex-smokers to cigarette smoke (smoking one cigarette) did not cause a dramatic change in the plasma miRNA profile. In conclusion, we found that repeated cigarette smoking substantially alters the plasma miRNA profile, interfering with the diagnosis of disease or signaling potential smoking-related diseases. - Highlights: • Plasma miRNA profiles were unambiguously different between smokers and non-smokers. • Smoking status might interfere with the diagnosis of disease using plasma miRNAs. • Changes of plasma miRNA profiles may be a signal of smoking-related diseases

  2. Both cis and trans Activities of Foot-and-Mouth Disease Virus 3D Polymerase Are Essential for Viral RNA Replication.

    Science.gov (United States)

    Herod, Morgan R; Ferrer-Orta, Cristina; Loundras, Eleni-Anna; Ward, Joseph C; Verdaguer, Nuria; Rowlands, David J; Stonehouse, Nicola J

    2016-08-01

    The Picornaviridae is a large family of positive-sense RNA viruses that contains numerous human and animal pathogens, including foot-and-mouth disease virus (FMDV). The picornavirus replication complex comprises a coordinated network of protein-protein and protein-RNA interactions involving multiple viral and host-cellular factors. Many of the proteins within the complex possess multiple roles in viral RNA replication, some of which can be provided in trans (i.e., via expression from a separate RNA molecule), while others are required in cis (i.e., expressed from the template RNA molecule). In vitro studies have suggested that multiple copies of the RNA-dependent RNA polymerase (RdRp) 3D are involved in the viral replication complex. However, it is not clear whether all these molecules are catalytically active or what other function(s) they provide. In this study, we aimed to distinguish between catalytically active 3D molecules and those that build a replication complex. We report a novel nonenzymatic cis-acting function of 3D that is essential for viral-genome replication. Using an FMDV replicon in complementation experiments, our data demonstrate that this cis-acting role of 3D is distinct from the catalytic activity, which is predominantly trans acting. Immunofluorescence studies suggest that both cis- and trans-acting 3D molecules localize to the same cellular compartment. However, our genetic and structural data suggest that 3D interacts in cis with RNA stem-loops that are essential for viral RNA replication. This study identifies a previously undescribed aspect of picornavirus replication complex structure-function and an important methodology for probing such interactions further. Foot-and-mouth disease virus (FMDV) is an important animal pathogen responsible for foot-and-mouth disease. The disease is endemic in many parts of the world with outbreaks within livestock resulting in major economic losses. Propagation of the viral genome occurs within

  3. Genetics and Molecular Biology of Epstein-Barr Virus-Encoded BART MicroRNA: A Paradigm for Viral Modulation of Host Immune Response Genes and Genome Stability

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    David H. Dreyfus

    2017-01-01

    Full Text Available Epstein-Barr virus, a ubiquitous human herpesvirus, is associated through epidemiologic evidence with common autoimmune syndromes and cancers. However, specific genetic mechanisms of pathogenesis have been difficult to identify. In this review, the author summarizes evidence that recently discovered noncoding RNAs termed microRNA encoded by Epstein-Barr virus BARF (BamHI A right frame termed BART (BamHI A right transcripts are modulators of human immune response genes and genome stability in infected and bystander cells. BART expression is apparently regulated by complex feedback loops with the host immune response regulatory NF-κB transcription factors. EBV-encoded BZLF-1 (ZEBRA protein could also regulate BART since ZEBRA contains a terminal region similar to ankyrin proteins such as IκBα that regulate host NF-κB. BALF-2 (BamHI A left frame transcript, a viral homologue of the immunoglobulin and T cell receptor gene recombinase RAG-1 (recombination-activating gene-1, may also be coregulated with BART since BALF-2 regulatory sequences are located near the BART locus. Viral-encoded microRNA and viral mRNA transferred to bystander cells through vesicles, defective viral particles, or other mechanisms suggest a new paradigm in which bystander or hit-and-run mechanisms enable the virus to transiently or chronically alter human immune response genes as well as the stability of the human genome.

  4. Extracellular tumor-related mRNA in plasma of lymphoma patients and survival implications.

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    Vanesa Garcia

    Full Text Available BACKGROUND: We studied anomalous extracellular mRNAs in plasma from patients with diffuse large B-cell lymphoma (DLBCL and their survival implications. mRNAs studied have been reported in the literature as markers of poor (BCL2, CCND2, MYC and favorable outcome (LMO2, BCL6, FN1 in tumors. These markers were also analyzed in lymphoma tissues to test possible associations with their presence in plasma. METHODOLOGY/PRINCIPAL FINDINGS: mRNA from 42 plasma samples and 12 tumors from patients with DLBCL was analyzed by real-time PCR. Samples post-treatment were studied. The immunohistochemistry of BCL2 and BCL6 was defined. Presence of circulating tumor cells was determined by analyzing the clonality of the immunoglobulin heavy-chain genes by PCR. In DLBCL, MYC mRNA was associated with short overall survival. mRNA targets with unfavorable outcome in tumors were associated with characteristics indicative of poor prognosis, with partial treatment response and with short progression-free survival in patients with complete response. In patients with low IPI score, unfavorable mRNA targets were related to shorter overall survival, partial response, high LDH levels and death. mRNA disappeared in post-treatment samples of patients with complete response, and persisted in those with partial response or death. No associations were found between circulating tumor cells and plasma mRNA. Absence of BCL6 protein in tumors was associated with presence of unfavorable plasma mRNA. CONCLUSIONS/SIGNIFICANCE: Through a non-invasive procedure, tumor-derived mRNAs can be obtained in plasma. mRNA detected in plasma did not proceed from circulating tumor cells. In our study, unfavorable targets in plasma were associated with poor prognosis in B-cell lymphomas, mainly MYC mRNA. Moreover, the unfavorable targets in plasma could help us to classify patients with poor outcome within the good prognosis group according to IPI.

  5. Recovery of viral RNA and infectious foot-and-mouth disease virus from positive lateral-flow devices.

    Science.gov (United States)

    Fowler, Veronica L; Bankowski, Bartlomiej M; Armson, Bryony; Di Nardo, Antonello; Valdazo-Gonzalez, Begoña; Reid, Scott M; Barnett, Paul V; Wadsworth, Jemma; Ferris, Nigel P; Mioulet, Valérie; King, Donald P

    2014-01-01

    Foot-and-mouth disease Virus (FMDV) is an economically important, highly contagious picornavirus that affects both wild and domesticated cloven hooved animals. In developing countries, the effective laboratory diagnosis of foot-and-mouth disease (FMD) is often hindered by inadequate sample preservation due to difficulties in the transportation and storage of clinical material. These factors can compromise the ability to detect and characterise FMD virus in countries where the disease is endemic. Furthermore, the high cost of sending infectious virus material and the biosecurity risk it presents emphasises the need for a thermo-stable, non-infectious mode of transporting diagnostic samples. This paper investigates the potential of using FMDV lateral-flow devices (LFDs) for dry transportation of clinical samples for subsequent nucleic acid amplification, sequencing and recovery of infectious virus by electroporation. FMDV positive samples (epithelial suspensions and cell culture isolates) representing four FMDV serotypes were applied to antigen LFDs: after which it was possible to recover viral RNA that could be detected using real-time RT-PCR. Using this nucleic acid, it was also possible to recover VP1 sequences and also successfully utilise protocols for amplification of complete FMD virus genomes. It was not possible to recover infectious FMDV directly from the LFDs, however following electroporation into BHK-21 cells and subsequent cell passage, infectious virus could be recovered. Therefore, these results support the use of the antigen LFD for the dry, non-hazardous transportation of samples from FMD endemic countries to international reference laboratories.

  6. The Complex Exogenous RNA Spectra in Human Plasma: An Interface with Human Gut Biota?

    Science.gov (United States)

    Wang, Kai; Li, Hong; Yuan, Yue; Etheridge, Alton; Zhou, Yong; Huang, David; Wilmes, Paul; Galas, David

    2012-01-01

    Human plasma has long been a rich source for biomarker discovery. It has recently become clear that plasma RNA molecules, such as microRNA, in addition to proteins are common and can serve as biomarkers. Surveying human plasma for microRNA biomarkers using next generation sequencing technology, we observed that a significant fraction of the circulating RNA appear to originate from exogenous species. With careful analysis of sequence error statistics and other controls, we demonstrated that there is a wide range of RNA from many different organisms, including bacteria and fungi as well as from other species. These RNAs may be associated with protein, lipid or other molecules protecting them from RNase activity in plasma. Some of these RNAs are detected in intracellular complexes and may be able to influence cellular activities under in vitro conditions. These findings raise the possibility that plasma RNAs of exogenous origin may serve as signaling molecules mediating for example the human-microbiome interaction and may affect and/or indicate the state of human health. PMID:23251414

  7. Long-term follow up of feline leukemia virus infection and characterization of viral RNA loads using molecular methods in tissues of cats with different infection outcomes.

    Science.gov (United States)

    Helfer-Hungerbuehler, A Katrin; Widmer, Stefan; Kessler, Yvonne; Riond, Barbara; Boretti, Felicitas S; Grest, Paula; Lutz, Hans; Hofmann-Lehmann, Regina

    2015-02-02

    It is a remarkable feature for a retrovirus that an infection with feline leukemia virus (FeLV) can result in various outcomes. Whereas some cats contain the infection and show a regressive course, others stay viremic and succumb to the infection within a few years. We hypothesized, that differences in the infection outcome might be causally linked to the viral RNA and provirus loads within the host and these loads therefore may give additional insight into the pathogenesis of the virus. Thus, the goals of the present study were to follow-up on experimentally infected cats and investigate tissues from cats with different infection outcomes using sensitive, specific TaqMan real-time PCR and reverse transcriptase (RT)-PCR. Nineteen experimentally FeLV-A/Glasgow-1-infected cats were categorized into having regressive, progressive or reactivated FeLV infection according to follow-up of FeLV p27 antigen detection in the blood. Remarkably, regressively infected cats showed detectable provirus and viral RNA loads in almost all of the 27 tested tissues, even many years after virus exposure. Moreover, some regressively infected cats reactivated the infection, and these cats had intermediate to high viral RNA and provirus tissue loads. The highest loads were found in viremic cats, independent of their health status. Tissues that represented sites of virus replication and shedding revealed the highest viral RNA and provirus loads, while the lowest loads were present in muscle and nerve tissues. A supplementary analysis of 20 experimentally infected cats with progressive infection revealed a median survival time of 3.1 years (range from 0.6 to 6.5 years); ∼70% (n=14) of these cats developed lymphoma, while leukemia and non-regenerative anemia were observed less frequently. Our results demonstrate that the different infection outcomes are associated with differences in viral RNA and provirus tissue loads. Remarkably, no complete clearance of FeLV viral RNA or provirus was

  8. Expression of microRNA related to bone remodeling regulation in plasma in patients with acromegaly

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    Tatiana A. Grebennikova

    2017-11-01

    Full Text Available Backgraund. MiсroRNA are small regulatory factors that regulate gene expression by post-transcriptional regulation of mRNA, playing an important role in numerous cellular processes including organogenesis, apoptosis, cell proliferation and differentiation. Acromegaly causes bone fragility, but the pathogenetic mechanism is generally unknown. Aim. To evaluate levels of microRNA related to bone remodeling regulation in plasma samples from patients with acromegaly Materials and methods. Fasting plasma samples were taken and stored in aliquot at ≤ -80°C from consecutive subjects with clinically evident and biochemically confirmed active acromegaly and healthy volunteers matched by age, sex and body mass index (BMI. miRNeasy Serum/Plasma Kit, TaqMan Advanced miRNA cDNA Synthesis Kit, TaqMan Advanced miRNA Assays were used to assay plasma miRNA expression. Insulin-like growth factor 1 (IGF1 was measured by immunochemiluminescence assay (Liaison. Results. We enrolled 40 subjects 22 patients suffered from acromegaly and 18 matched healthy controls matched by sex, age and BMI. The median age of patients with acromegaly was 42 years (Q25;Q75 – 37;43 with no difference among the groups, p=0.205; BMI – 28 (24;32 kg/m2, p=0.253. The median IGF1 in subjects with acromegaly – 622 (514;1000 ng/ml was significantly higher as compared to the control group (p<0.001. Patients with acromegaly had significantly higher expression of microRNA-100-5р (p=0.051, microRNA-550а-5р (p=0.048, microRNA-7b-5р (p=0.005 and microRNA-96-5р (p=0.042 among 27 bone-specific microRNA tested in plasma Conclusions. This study reveals that several microRNAs, known to regulate bone remodeling can be detected in plasma samples of patients with acromegaly and may be suggested as biomarkers for skeletal involvement in patients with acromegaly.

  9. Suppression of injuries caused by a lytic RNA virus (mengovirus) and their uncoupling from viral reproduction by mutual cell/virus disarmament.

    Science.gov (United States)

    Mikitas, Olga V; Ivin, Yuri Y; Golyshev, Sergey A; Povarova, Natalia V; Galkina, Svetlana I; Pletjushkina, Olga Y; Nadezhdina, Elena S; Gmyl, Anatoly P; Agol, Vadim I

    2012-05-01

    Viruses often elicit cell injury (cytopathic effect [CPE]), a major cause of viral diseases. CPE is usually considered to be a prerequisite for and/or consequence of efficient viral growth. Recently, we proposed that viral CPE may largely be due to host defensive and viral antidefensive activities. This study aimed to check the validity of this proposal by using as a model HeLa cells infected with mengovirus (MV). As we showed previously, infection of these cells with wild-type MV resulted in necrosis, whereas a mutant with incapacitated antidefensive ("security") viral leader (L) protein induced apoptosis. Here, we showed that several major morphological and biochemical signs of CPE (e.g., alterations in cellular and nuclear shape, plasma membrane, cytoskeleton, chromatin, and metabolic activity) in cells infected with L(-) mutants in the presence of an apoptosis inhibitor were strongly suppressed or delayed for long after completion of viral reproduction. These facts demonstrate that the efficient reproduction of a lytic virus may not directly require development of at least some pathological alterations normally accompanying infection. They also imply that L protein is involved in the control of many apparently unrelated functions. The results also suggest that the virus-activated program with competing necrotic and apoptotic branches is host encoded, with the choice between apoptosis and necrosis depending on a variety of intrinsic and extrinsic conditions. Implementation of this defensive suicidal program could be uncoupled from the viral reproduction. The possibility of such uncoupling has significant implications for the pathogenesis and treatment of viral diseases.

  10. Replicative homeostasis II: Influence of polymerase fidelity on RNA virus quasispecies biology: Implications for immune recognition, viral autoimmunity and other "virus receptor" diseases

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    Sallie Richard

    2005-08-01

    Full Text Available Abstract Much of the worlds' population is in active or imminent danger from established infectious pathogens, while sporadic and pandemic infections by these and emerging agents threaten everyone. RNA polymerases (RNApol generate enormous genetic and consequent antigenic heterogeneity permitting both viruses and cellular pathogens to evade host defences. Thus, RNApol causes more morbidity and premature mortality than any other molecule. The extraordinary genetic heterogeneity defining viral quasispecies results from RNApol infidelity causing rapid cumulative genomic RNA mutation a process that, if uncontrolled, would cause catastrophic loss of sequence integrity and inexorable quasispecies extinction. Selective replication and replicative homeostasis, an epicyclical regulatory mechanism dynamically linking RNApol fidelity and processivity with quasispecies phenotypic diversity, modulating polymerase fidelity and, hence, controlling quasispecies behaviour, prevents this happening and also mediates immune escape. Perhaps more importantly, ineluctable generation of broad phenotypic diversity after viral RNA is translated to protein quasispecies suggests a mechanism of disease that specifically targets, and functionally disrupts, the host cell surface molecules – including hormone, lipid, cell signalling or neurotransmitter receptors – that viruses co-opt for cell entry. This mechanism – "Viral Receptor Disease (VRD" – may explain so-called "viral autoimmunity", some classical autoimmune disorders and other diseases, including type II diabetes mellitus, and some forms of obesity. Viral receptor disease is a unifying hypothesis that may also explain some diseases with well-established, but multi-factorial and apparently unrelated aetiologies – like coronary artery and other vascular diseases – in addition to diseases like schizophrenia that are poorly understood and lack plausible, coherent, pathogenic explanations.

  11. Clinical significance of measurement of changes of serum NSE and plasma NPY levels after treatment in pediatric patients with viral encephalitis

    International Nuclear Information System (INIS)

    Jin Bo; Zheng Guo

    2007-01-01

    Objective: To explore the significance ef changes of serum NSE and plasma NPY levels after treatment in pediatric patients with viral encephalitis. Methods: Serum NSE and plasma NPY levels were measured with RIA in 32 pediatric patients with viral encephalitis both before and after treatment as well as in 30 controls. Results: Before treatment, in the patients, the serum NSE and plasma NPY levels were significantly higher than those in controls (P<0.01). After 1 month's treatment the levels dropped markedly but still remained significantly higher than those in controls (P<0.05). Conclusion: Serum NSE and plasma NPY levels changes were closely related to the progress of viral encephalitis. (authors)

  12. RNA helicase MOV10 functions as a co-factor of HIV-1 Rev to facilitate Rev/RRE-dependent nuclear export of viral mRNAs

    International Nuclear Information System (INIS)

    Huang, Feng; Zhang, Junsong; Zhang, Yijun; Geng, Guannan; Liang, Juanran; Li, Yingniang; Chen, Jingliang; Liu, Chao; Zhang, Hui

    2015-01-01

    Human immunodeficiency virus type 1 (HIV-1) exploits multiple host factors during its replication. The REV/RRE-dependent nuclear export of unspliced/partially spliced viral transcripts needs the assistance of host proteins. Recent studies have shown that MOV10 overexpression inhibited HIV-1 replication at various steps. However, the endogenous MOV10 was required in certain step(s) of HIV-1 replication. In this report, we found that MOV10 potently enhances the nuclear export of viral mRNAs and subsequently increases the expression of Gag protein and other late products through affecting the Rev/RRE axis. The co-immunoprecipitation analysis indicated that MOV10 interacts with Rev in an RNA-independent manner. The DEAG-box of MOV10 was required for the enhancement of Rev/RRE-dependent nuclear export and the DEAG-box mutant showed a dominant-negative activity. Our data propose that HIV-1 utilizes the anti-viral factor MOV10 to function as a co-factor of Rev and demonstrate the complicated effects of MOV10 on HIV-1 life cycle. - Highlights: • MOV10 can function as a co-factor of HIV-1 Rev. • MOV10 facilitates Rev/RRE-dependent transport of viral mRNAs. • MOV10 interacts with Rev in an RNA-independent manner. • The DEAG-box of MOV10 is required for the enhancement of Rev/RRE-dependent export.

  13. RNA helicase MOV10 functions as a co-factor of HIV-1 Rev to facilitate Rev/RRE-dependent nuclear export of viral mRNAs

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Feng; Zhang, Junsong; Zhang, Yijun; Geng, Guannan; Liang, Juanran; Li, Yingniang; Chen, Jingliang [Institute of Human Virology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou 510080 (China); Key Laboratory of Tropical Disease Control of Ministry of Education, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou 510080 (China); Liu, Chao, E-mail: liuchao9@mail.sysu.edu.cn [Institute of Human Virology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou 510080 (China); Key Laboratory of Tropical Disease Control of Ministry of Education, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou 510080 (China); Zhang, Hui [Institute of Human Virology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou 510080 (China); Key Laboratory of Tropical Disease Control of Ministry of Education, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou 510080 (China)

    2015-12-15

    Human immunodeficiency virus type 1 (HIV-1) exploits multiple host factors during its replication. The REV/RRE-dependent nuclear export of unspliced/partially spliced viral transcripts needs the assistance of host proteins. Recent studies have shown that MOV10 overexpression inhibited HIV-1 replication at various steps. However, the endogenous MOV10 was required in certain step(s) of HIV-1 replication. In this report, we found that MOV10 potently enhances the nuclear export of viral mRNAs and subsequently increases the expression of Gag protein and other late products through affecting the Rev/RRE axis. The co-immunoprecipitation analysis indicated that MOV10 interacts with Rev in an RNA-independent manner. The DEAG-box of MOV10 was required for the enhancement of Rev/RRE-dependent nuclear export and the DEAG-box mutant showed a dominant-negative activity. Our data propose that HIV-1 utilizes the anti-viral factor MOV10 to function as a co-factor of Rev and demonstrate the complicated effects of MOV10 on HIV-1 life cycle. - Highlights: • MOV10 can function as a co-factor of HIV-1 Rev. • MOV10 facilitates Rev/RRE-dependent transport of viral mRNAs. • MOV10 interacts with Rev in an RNA-independent manner. • The DEAG-box of MOV10 is required for the enhancement of Rev/RRE-dependent export.

  14. Mutational Analysis of the Hypervariable Region of Hepatitis E Virus Reveals Its Involvement in the Efficiency of Viral RNA Replication ▿

    OpenAIRE

    Pudupakam, R. S.; Kenney, Scott P.; Córdoba, Laura; Huang, Yao-Wei; Dryman, Barbara A.; LeRoith, Tanya; Pierson, F. William; Meng, Xiang-Jin

    2011-01-01

    The RNA genome of the hepatitis E virus (HEV) contains a hypervariable region (HVR) in ORF1 that tolerates small deletions with respect to infectivity. To further investigate the role of the HVR in HEV replication, we constructed a panel of mutants with overlapping deletions in the N-terminal, central, and C-terminal regions of the HVR by using a genotype 1 human HEV luciferase replicon and analyzed the effects of deletions on viral RNA replication in Huh7 cells. We found that the replication...

  15. Viral uncoating is directional: exit of the genomic RNA in a common cold virus starts with the poly-(A tail at the 3'-end.

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    Shushan Harutyunyan

    Full Text Available Upon infection, many RNA viruses reorganize their capsid for release of the genome into the host cell cytosol for replication. Often, this process is triggered by receptor binding and/or by the acidic environment in endosomes. In the genus Enterovirus, which includes more than 150 human rhinovirus (HRV serotypes causing the common cold, there is persuasive evidence that the viral RNA exits single-stranded through channels formed in the protein shell. We have determined the time-dependent emergence of the RNA ends from HRV2 on incubation of virions at 56°C using hybridization with specific oligonucleotides and detection by fluorescence correlation spectroscopy. We report that psoralen UV crosslinking prevents complete RNA release, allowing for identification of the sequences remaining inside the capsid. We also present the structure of uncoating intermediates in which parts of the RNA are condensed and take the form of a rod that is directed roughly towards a two-fold icosahedral axis, the presumed RNA exit point. Taken together, in contrast to schemes frequently depicted in textbooks and reviews, our findings demonstrate that exit of the RNA starts from the 3'-end. This suggests that packaging also occurs in an ordered manner resulting in the 3'-poly-(A tail becoming located close to a position of pore formation during conversion of the virion into a subviral particle. This directional genome release may be common to many icosahedral non-enveloped single-stranded RNA viruses.

  16. Regulation of c-myc and c-fos mRNA levels by polyomavirus: distinct roles for the capsid protein VP1 and the viral early proteins

    International Nuclear Information System (INIS)

    Zullo, J.; Stiles, C.D.; Garcea, R.L.

    1987-01-01

    The levels of c-myc, c-fos, and JE mRNAs accumulate in a biphasic pattern following infection of quiescent BALB/c 3T3 mouse cells with polyomavirus. Maximal levels of c-myc and c-fos mRNAs were seen within 1 hr and were nearly undetectable at 6 hr after infection. At 12 hr after infection mRNA levels were again maximal and remained elevated thereafter. Empty virions (capsids) and recombinant VP 1 protein, purified from Escherichia coli, induced the early but not the late phase of mRNA accumulation. Virions, capsids, and recombinant VP 1 protein stimulated [ 3 H]thymidine nuclear labeling and c-myc mRNA accumulation in a dose-responsive manner paralleling their affinity for the cell receptor for polyoma. The second phase of mRNA accumulation is regulated by the viral early gene products, as shown by polyomavirus early gene mutants and by a transfected cell line (336a) expressing middle tumor antigen upon glucocorticoid addition. These results suggest that polyomavirus interacts with the cell membrane at the onset of infection to increase the levels of mRNA for the cellular genes associated with cell competence for DNA replication, and subsequently these levels are maintained by the action of the early viral proteins

  17. Exposure to the viral by-product dsRNA or Coxsackievirus B5 triggers pancreatic beta cell apoptosis via a Bim / Mcl-1 imbalance.

    Directory of Open Access Journals (Sweden)

    Maikel L Colli

    2011-09-01

    Full Text Available The rise in type 1 diabetes (T1D incidence in recent decades is probably related to modifications in environmental factors. Viruses are among the putative environmental triggers of T1D. The mechanisms regulating beta cell responses to viruses, however, remain to be defined. We have presently clarified the signaling pathways leading to beta cell apoptosis following exposure to the viral mimetic double-stranded RNA (dsRNA and a diabetogenic enterovirus (Coxsackievirus B5. Internal dsRNA induces cell death via the intrinsic mitochondrial pathway. In this process, activation of the dsRNA-dependent protein kinase (PKR promotes eIF2α phosphorylation and protein synthesis inhibition, leading to downregulation of the antiapoptotic Bcl-2 protein myeloid cell leukemia sequence 1 (Mcl-1. Mcl-1 decrease results in the release of the BH3-only protein Bim, which activates the mitochondrial pathway of apoptosis. Indeed, Bim knockdown prevented both dsRNA- and Coxsackievirus B5-induced beta cell death, and counteracted the proapoptotic effects of Mcl-1 silencing. These observations indicate that the balance between Mcl-1 and Bim is a key factor regulating beta cell survival during diabetogenic viral infections.

  18. Recovery of viral RNA and infectious foot-and-mouth disease virus from positive lateral-flow devices.

    Directory of Open Access Journals (Sweden)

    Veronica L Fowler

    Full Text Available Foot-and-mouth disease Virus (FMDV is an economically important, highly contagious picornavirus that affects both wild and domesticated cloven hooved animals. In developing countries, the effective laboratory diagnosis of foot-and-mouth disease (FMD is often hindered by inadequate sample preservation due to difficulties in the transportation and storage of clinical material. These factors can compromise the ability to detect and characterise FMD virus in countries where the disease is endemic. Furthermore, the high cost of sending infectious virus material and the biosecurity risk it presents emphasises the need for a thermo-stable, non-infectious mode of transporting diagnostic samples. This paper investigates the potential of using FMDV lateral-flow devices (LFDs for dry transportation of clinical samples for subsequent nucleic acid amplification, sequencing and recovery of infectious virus by electroporation. FMDV positive samples (epithelial suspensions and cell culture isolates representing four FMDV serotypes were applied to antigen LFDs: after which it was possible to recover viral RNA that could be detected using real-time RT-PCR. Using this nucleic acid, it was also possible to recover VP1 sequences and also successfully utilise protocols for amplification of complete FMD virus genomes. It was not possible to recover infectious FMDV directly from the LFDs, however following electroporation into BHK-21 cells and subsequent cell passage, infectious virus could be recovered. Therefore, these results support the use of the antigen LFD for the dry, non-hazardous transportation of samples from FMD endemic countries to international reference laboratories.

  19. hnRNP A2/B1 interacts with influenza A viral protein NS1 and inhibits virus replication potentially through suppressing NS1 RNA/protein levels and NS1 mRNA nuclear export

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Yimeng; Zhou, Jianhong; Du, Yuchun, E-mail: ydu@uark.edu

    2014-01-20

    The NS1 protein of influenza viruses is a major virulence factor and exerts its function through interacting with viral/cellular RNAs and proteins. In this study, we identified heterogeneous nuclear ribonucleoprotein A2/B1 (hnRNP A2/B1) as an interacting partner of NS1 proteins by a proteomic method. Knockdown of hnRNP A2/B1 by small interfering RNA (siRNA) resulted in higher levels of NS vRNA, NS1 mRNA, and NS1 protein in the virus-infected cells. In addition, we demonstrated that hnRNP A2/B1 proteins are associated with NS1 and NS2 mRNAs and that knockdown of hnRNP A2/B1 promotes transport of NS1 mRNA from the nucleus to the cytoplasm in the infected cells. Lastly, we showed that knockdown of hnRNP A2/B1 leads to enhanced virus replication. Our results suggest that hnRNP A2/B1 plays an inhibitory role in the replication of influenza A virus in host cells potentially through suppressing NS1 RNA/protein levels and NS1 mRNA nucleocytoplasmic translocation. - Highlights: • Cellular protein hnRNP A2/B1 interacts with influenza viral protein NS1. • hnRNP A2/B1 suppresses the levels of NS1 protein, vRNA and mRNA in infected cells. • hnRNP A2/B1 protein is associated with NS1 and NS2 mRNAs. • hnRNP A2/B1 inhibits the nuclear export of NS1 mRNAs. • hnRNP A2/B1 inhibits influenza virus replication.

  20. Viral RNA silencing suppression

    NARCIS (Netherlands)

    Hedil, Marcio; Kormelink, Richard

    2016-01-01

    The Bunyaviridae is a family of arboviruses including both plant-and vertebrate-infecting representatives. The Tospovirus genus accommodates plant-infecting bunyaviruses, which not only replicate in their plant host, but also in their insect thrips vector during persistent propagative

  1. Plasma processing conditions substantially influence circulating microRNA biomarker levels.

    Science.gov (United States)

    Cheng, Heather H; Yi, Hye Son; Kim, Yeonju; Kroh, Evan M; Chien, Jason W; Eaton, Keith D; Goodman, Marc T; Tait, Jonathan F; Tewari, Muneesh; Pritchard, Colin C

    2013-01-01

    Circulating, cell-free microRNAs (miRNAs) are promising candidate biomarkers, but optimal conditions for processing blood specimens for miRNA measurement remain to be established. Our previous work showed that the majority of plasma miRNAs are likely blood cell-derived. In the course of profiling lung cancer cases versus healthy controls, we observed a broad increase in circulating miRNA levels in cases compared to controls and that higher miRNA expression correlated with higher platelet and particle counts. We therefore hypothesized that the quantity of residual platelets and microparticles remaining after plasma processing might impact miRNA measurements. To systematically investigate this, we subjected matched plasma from healthy individuals to stepwise processing with differential centrifugation and 0.22 µm filtration and performed miRNA profiling. We found a major effect on circulating miRNAs, with the majority (72%) of detectable miRNAs substantially affected by processing alone. Specifically, 10% of miRNAs showed 4-30x variation, 46% showed 30-1,000x variation, and 15% showed >1,000x variation in expression solely from processing. This was predominantly due to platelet contamination, which persisted despite using standard laboratory protocols. Importantly, we show that platelet contamination in archived samples could largely be eliminated by additional centrifugation, even in frozen samples stored for six years. To minimize confounding effects in microRNA biomarker studies, additional steps to limit platelet contamination for circulating miRNA biomarker studies are necessary. We provide specific practical recommendations to help minimize confounding variation attributable to plasma processing and platelet contamination.

  2. Improved detection of Bovine Viral Diarrhea Virus in Bovine lymphoid cell lines using PrimeFlow RNA assay

    Science.gov (United States)

    Bovine viral diarrhea virus (BVDV) infections, whether as acute, persistent or contributing to co-infections, result in significant losses for cattle producers. BVDV can be identified by real-time PCR and ELISA, detection and quantification of viral infection at the single cell level is extremely di...

  3. RNA Binding Protein RBM38 Regulates Expression of the 11-Kilodalton Protein of Parvovirus B19, Which Facilitates Viral DNA Replication.

    Science.gov (United States)

    Ganaie, Safder S; Chen, Aaron Yun; Huang, Chun; Xu, Peng; Kleiboeker, Steve; Du, Aifang; Qiu, Jianming

    2018-04-15

    Human parvovirus B19 (B19V) expresses a single precursor mRNA (pre-mRNA), which undergoes alternative splicing and alternative polyadenylation to generate 12 viral mRNA transcripts that encode two structural proteins (VP1 and VP2) and three nonstructural proteins (NS1, 7.5-kDa protein, and 11-kDa protein). Splicing at the second 5' donor site (D2 site) of the B19V pre-mRNA is essential for the expression of VP2 and the 11-kDa protein. We previously identified that cis -acting intronic splicing enhancer 2 (ISE2) that lies immediately after the D2 site facilitates the recognition of the D2 donor for its efficient splicing. In this study, we report that ISE2 is critical for the expression of the 11-kDa viral nonstructural protein. We found that ISE2 harbors a consensus RNA binding motif protein 38 (RBM38) binding sequence, 5'-UGUGUG-3'. RBM38 is expressed during the middle stage of erythropoiesis. We first confirmed that RBM38 binds specifically with the ISE2 element in vitro The knockdown of RBM38 significantly decreases the level of spliced mRNA at D2 that encodes the 11-kDa protein but not that of the D2-spliced mRNA that encodes VP2. Importantly, we found that the 11-kDa protein enhances viral DNA replication and virion release. Accordingly, the knockdown of RBM38 decreases virus replication via downregulating 11-kDa protein expression. Taken together, these results suggest that the 11-kDa protein facilitates B19V DNA replication and that RBM38 is an essential host factor for B19V pre-mRNA splicing and for the expression of the 11-kDa protein. IMPORTANCE B19V is a human pathogen that can cause fifth disease, arthropathy, anemia in immunocompromised patients and sickle cell disease patients, myocarditis, and hydrops fetalis in pregnant women. Human erythroid progenitor cells (EPCs) are most susceptible to B19V infection and fully support viral DNA replication. The exclusive tropism of B19V for erythroid-lineage cells is dependent not only on the expression of viral

  4. Plasma and White Blood Cells Show Different miRNA Expression Profiles in Parkinson's Disease.

    Science.gov (United States)

    Schwienbacher, Christine; Foco, Luisa; Picard, Anne; Corradi, Eloina; Serafin, Alice; Panzer, Jörg; Zanigni, Stefano; Blankenburg, Hagen; Facheris, Maurizio F; Giannini, Giulia; Falla, Marika; Cortelli, Pietro; Pramstaller, Peter P; Hicks, Andrew A

    2017-06-01

    Parkinson's disease (PD) diagnosis is based on the assessment of motor symptoms, which manifest when more than 50% of dopaminergic neurons are degenerated. To date, no validated biomarkers are available for the diagnosis of PD. The aims of the present study are to evaluate whether plasma and white blood cells (WBCs) are interchangeable biomarker sources and to identify circulating plasma-based microRNA (miRNA) biomarkers for an early detection of PD. We profiled plasma miRNA levels in 99 L-dopa-treated PD patients from two independent data collections, in ten drug-naïve PD patients, and in unaffected controls matched by sex and age. We evaluated expression levels by reverse transcription and quantitative real-time PCR (RT-qPCR) and combined the results from treated PD patients using a fixed effect inverse-variance weighted meta-analysis. We revealed different expression profiles comparing plasma and WBCs and drug-naïve and L-dopa-treated PD patients. We observed an upregulation trend for miR-30a-5p in L-dopa-treated PD patients and investigated candidate target genes by integrated in silico analyses. We could not analyse miR-29b-3p, normally expressed in WBCs, due to the very low expression in plasma. We observed different expression profiles in WBCs and plasma, suggesting that they are both suitable but not interchangeable peripheral sources for biomarkers. We revealed miR-30a-5p as a potential biomarker for PD in plasma. In silico analyses suggest that miR-30a-5p might have a regulatory role in mitochondrial dynamics and autophagy. Further investigations are needed to confirm miR-30a-5p deregulation and targets and to investigate the influence of L-dopa treatment on miRNA expression levels.

  5. Mutational Analysis of the Hypervariable Region of Hepatitis E Virus Reveals Its Involvement in the Efficiency of Viral RNA Replication ▿

    Science.gov (United States)

    Pudupakam, R. S.; Kenney, Scott P.; Córdoba, Laura; Huang, Yao-Wei; Dryman, Barbara A.; LeRoith, Tanya; Pierson, F. William; Meng, Xiang-Jin

    2011-01-01

    The RNA genome of the hepatitis E virus (HEV) contains a hypervariable region (HVR) in ORF1 that tolerates small deletions with respect to infectivity. To further investigate the role of the HVR in HEV replication, we constructed a panel of mutants with overlapping deletions in the N-terminal, central, and C-terminal regions of the HVR by using a genotype 1 human HEV luciferase replicon and analyzed the effects of deletions on viral RNA replication in Huh7 cells. We found that the replication levels of the HVR deletion mutants were markedly reduced in Huh7 cells, suggesting a role of the HVR in viral replication efficiency. To further verify the results, we constructed HVR deletion mutants by using a genetically divergent, nonmammalian avian HEV, and similar effects on viral replication efficiency were observed when the avian HEV mutants were tested in LMH cells. Furthermore, the impact of complete HVR deletion on virus infectivity was tested in chickens, using an avian HEV mutant with a complete HVR deletion. Although the deletion mutant was still replication competent in LMH cells, the complete HVR deletion resulted in a loss of avian HEV infectivity in chickens. Since the HVR exhibits extensive variations in sequence and length among different HEV genotypes, we further examined the interchangeability of HVRs and demonstrated that HVR sequences are functionally exchangeable between HEV genotypes with regard to viral replication and infectivity in vitro, although genotype-specific HVR differences in replication efficiency were observed. The results showed that although the HVR tolerates small deletions with regard to infectivity, it may interact with viral and host factors to modulate the efficiency of HEV replication. PMID:21775444

  6. Related factors to atazanavir plasma levels in a cohort of HIV positive individuals with undetectable viral load

    Directory of Open Access Journals (Sweden)

    Ana Júlia Luz

    Full Text Available OBJECTIVE: To evaluate the factors associated with plasma concentrations of atazanavir (ATV in a cohort of well-controlled HIV infected subjects (undetectable viremia. Design: Cross-sectional study where 69 subjects were consecutively enrolled between April and November, 2011. METHODS: Patients had to be on atazanavir for at least six months, undetectable viral load for a period equal to or longer than 12 months, T CD4+ lymphocyte count higher than 200 cells/mm³, and aged between 18 years and 70 years old. Exclusion criteria were pregnancy, any neurologic disease, active opportunistic disease, hepatitis or cancer. Atazanavir plasma levels were measured by ultra-performance liquid chromatography. RESULTS AND DISCUSSION: Overall, 54 patients (mean age of 47 years and 50% women were included in the analysis. Those without ritonavir (unboosted atazanavir had statistically lower plasma concentrations than those with ritonavir boosted atazanavir (p = 0.001 and total and indirect bilirubin were statistically associated with plasma concentration of atazanavir (r = 0.32 and r = 0.33 respectively; p < 0.05 in both cases. no statistical association was found among gender, ethnicity, age, weight, body mass index (BMI, lipid profile, and the plasma concentration of atazanavir. CONCLUSION: in summary, as expected, concomitant ritonavir use was the only factor associated with atazanavir plasma levels. prospective studies with a larger sample size might help to observe an association of atazanavir concentrations to other characteristics such as body weight, since the p-value showed to be close to significance (p = 0.068.

  7. The hepatitis C virus Core protein is a potent nucleic acid chaperone that directs dimerization of the viral (+) strand RNA in vitro.

    Science.gov (United States)

    Cristofari, Gaël; Ivanyi-Nagy, Roland; Gabus, Caroline; Boulant, Steeve; Lavergne, Jean-Pierre; Penin, François; Darlix, Jean-Luc

    2004-01-01

    The hepatitis C virus (HCV) is an important human pathogen causing chronic hepatitis, liver cirrhosis and hepatocellular carcinoma. HCV is an enveloped virus with a positive-sense, single-stranded RNA genome encoding a single polyprotein that is processed to generate viral proteins. Several hundred molecules of the structural Core protein are thought to coat the genome in the viral particle, as do nucleocapsid (NC) protein molecules in Retroviruses, another class of enveloped viruses containing a positive-sense RNA genome. Retroviral NC proteins also possess nucleic acid chaperone properties that play critical roles in the structural remodelling of the genome during retrovirus replication. This analogy between HCV Core and retroviral NC proteins prompted us to investigate the putative nucleic acid chaperoning properties of the HCV Core protein. Here we report that Core protein chaperones the annealing of complementary DNA and RNA sequences and the formation of the most stable duplex by strand exchange. These results show that the HCV Core is a nucleic acid chaperone similar to retroviral NC proteins. We also find that the Core protein directs dimerization of HCV (+) RNA 3' untranslated region which is promoted by a conserved palindromic sequence possibly involved at several stages of virus replication.

  8. Inhibition of Hepatitis C Virus in Mice by a Small Interfering RNA Targeting a Highly Conserved Sequence in Viral IRES Pseudoknot.

    Directory of Open Access Journals (Sweden)

    Jae-Su Moon

    Full Text Available The hepatitis C virus (HCV internal ribosome entry site (IRES that directs cap-independent viral translation is a primary target for small interfering RNA (siRNA-based HCV antiviral therapy. However, identification of potent siRNAs against HCV IRES by bioinformatics-based siRNA design is a challenging task given the complexity of HCV IRES secondary and tertiary structures and association with multiple proteins, which can also dynamically change the structure of this cis-acting RNA element. In this work, we utilized siRNA tiling approach whereby siRNAs were tiled with overlapping sequences that were shifted by one or two nucleotides over the HCV IRES stem-loop structures III and IV spanning nucleotides (nts 277-343. Based on their antiviral activity, we mapped a druggable region (nts 313-343 where the targets of potent siRNAs were enriched. siIE22, which showed the greatest anti-HCV potency, targeted a highly conserved sequence across diverse HCV genotypes, locating within the IRES subdomain IIIf involved in pseudoknot formation. Stepwise target shifting toward the 5' or 3' direction by 1 or 2 nucleotides reduced the antiviral potency of siIE22, demonstrating the importance of siRNA accessibility to this highly structured and sequence-conserved region of HCV IRES for RNA interference. Nanoparticle-mediated systemic delivery of the stability-improved siIE22 derivative gs_PS1 siIE22, which contains a single phosphorothioate linkage on the guide strand, reduced the serum HCV genome titer by more than 4 log10 in a xenograft mouse model for HCV replication without generation of resistant variants. Our results provide a strategy for identifying potent siRNA species against a highly structured RNA target and offer a potential pan-HCV genotypic siRNA therapy that might be beneficial for patients resistant to current treatment regimens.

  9. Association between the miRNA Signatures in Plasma and Bronchoalveolar Fluid in Respiratory Pathologies

    Directory of Open Access Journals (Sweden)

    Sonia Molina-Pinelo

    2012-01-01

    Full Text Available The identification of new less invasive biomarkers is necessary to improve the detection and prognostic outcome of respiratory pathological processes. The measurement of miRNA expression through less invasive techniques such as plasma and serum have been suggested to analysis of several lung malignancies including lung cancer. These studies are assuming a common deregulated miRNA expression both in blood and lung tissue. The present study aimed to obtain miRNA representative signatures both in plasma and bronchoalveolar cell fraction that could serve as biomarker in respiratory diseases. Ten patients were evaluated to assess the expression levels of 381 miRNAs. We found that around 50% miRNAs were no detected in both plasma and bronchoalveolar cell fraction and only 20% of miRNAs showed similar expression in both samples. These results show a lack of association of miRNA signatures between plasma and bronchoalveolar cytology in the same patient. The profiles are not comparable; however, there is a similarity in the relative expression in a very small subset of miRNAs (miR-17, miR-19b, miR-195 and miR-20b between both biological samples in all patients. This finding supports that the miRNAs profiles obtained from different biological samples have to be carefully validated to link with respiratory diseases.

  10. Plasma microRNA profiles distinguish lethal injury in acetaminophen toxicity: A research study

    Institute of Scientific and Technical Information of China (English)

    Jeanine Ward; Shashi Bala; Jan Petrasek; Gyongyi Szabo

    2012-01-01

    AIM:To investigate plasma microRNA (miRNA) profiles indicative of hepatotoxicity in the setting of lethal acetaminophen (APAP) toxicity in mice.METHODS:Using plasma from APAP poisoned mice,either lethally (500 mg/kg) or sublethally (150 mg/kg) dosed,we screened commercially available murine microRNA libraries (SABiosciences,Qiagen Sciences,MD) to evaluate for unique miRNA profiles between these two dosing parameters.RESULTS:We distinguished numerous,unique plasma miRNAs both up- and downregulated in lethally compared to sublethally dosed mice.Of note,many of the greatest up- and downregulated miRNAs,namely 574-5p,466g,466f-3p,375,29c,and 148a,have been shown to be associated with asthma in prior studies.Interestingly,a relationship between APAP and asthma has been previously well described in the literature,with an as yet unknown mechanism of pathology.There was a statistically significant increase in alanine aminotransferase levels in the lethal compared to sublethal APAP dosing groups at the 12 h time point (P <0.001).There was 90% mortality in the lethally compared to sublethally dosed mice at the 48 h time point (P =0.011).CONCLUSION:We identified unique plasma miRNAs both up- and downregulated in APAP poisoning which are correlated to asthma development.

  11. Residual viraemia in HIV-1-infected patients with plasma viral load

    DEFF Research Database (Denmark)

    Ostrowski, S R; Katzenstein, T L; Pedersen, B K

    2008-01-01

    Despite undetectable viral load in conventional assays, probably all human immunodeficiency virus (HIV)-1 infected patients have residual viraemia (RV) detectable by ultra-sensitive assays. To study this issue, this study investigated virologic and immunologic consequences of RV in highly active......-count, CD4+HLA-DR+, CD8+HLA-DR+CD38+, CD4+CD45RA-CD45RO+, CD8+CD45RA-CD45RO+, CD4+CD45RA+CD62L+, CD8+CD45RA+CD62L+ T cells, IgG or IgM. In conclusion, RV was associated with increased blood levels of soluble immune activation markers in HAART-treated HIV-1-infected patients. The finding that RV...... antiretroviral therapy (HAART)-treated HIV-1-infected patients with plasma HIV-1 RNA or=1 episode with TMA-RV whereas 9 patients had undetectable TMA-RV throughout the study-period. Time-points with TMA-RV and PCR-RV were associated with higher circulating sTNFrII (+0.234 ng/ml, P = 0.030) and beta(2...

  12. Rational design of human metapneumovirus live attenuated vaccine candidates by inhibiting viral mRNA cap methyltransferase.

    Science.gov (United States)

    Zhang, Yu; Wei, Yongwei; Zhang, Xiaodong; Cai, Hui; Niewiesk, Stefan; Li, Jianrong

    2014-10-01

    The paramyxoviruses human respiratory syncytial virus (hRSV), human metapneumovirus (hMPV), and human parainfluenza virus type 3 (hPIV3) are responsible for the majority of pediatric respiratory diseases and inflict significant economic loss, health care costs, and emotional burdens. Despite major efforts, there are no vaccines available for these viruses. The conserved region VI (CR VI) of the large (L) polymerase proteins of paramyxoviruses catalyzes methyltransferase (MTase) activities that typically methylate viral mRNAs at positions guanine N-7 (G-N-7) and ribose 2'-O. In this study, we generated a panel of recombinant hMPVs carrying mutations in the S-adenosylmethionine (SAM) binding site in CR VI of L protein. These recombinant viruses were specifically defective in ribose 2'-O methylation but not G-N-7 methylation and were genetically stable and highly attenuated in cell culture and viral replication in the upper and lower respiratory tracts of cotton rats. Importantly, vaccination of cotton rats with these recombinant hMPVs (rhMPVs) with defective MTases triggered a high level of neutralizing antibody, and the rats were completely protected from challenge with wild-type rhMPV. Collectively, our results indicate that (i) amino acid residues in the SAM binding site in the hMPV L protein are essential for 2'-O methylation and (ii) inhibition of mRNA cap MTase can serve as a novel target to rationally design live attenuated vaccines for hMPV and perhaps other paramyxoviruses, such as hRSV and hPIV3. Human paramyxoviruses, including hRSV, hMPV, and hPIV3, cause the majority of acute upper and lower respiratory tract infections in humans, particularly in infants, children, the elderly, and immunocompromised individuals. Currently, there is no licensed vaccine available. A formalin-inactivated vaccine is not suitable for these viruses because it causes enhanced lung damage upon reinfection with the same virus. A live attenuated vaccine is the most promising

  13. A Tiny RNA that Packs a Big Punch: The Critical Role of a Viral miR-155 Ortholog in Lymphomagenesis in Marek’s Disease

    Directory of Open Access Journals (Sweden)

    Guoqing Zhuang

    2017-06-01

    Full Text Available MicroRNAs (miRNAs are small non-coding RNAs that have been identified in animals, plants, and viruses. These small RNAs play important roles in post-transcriptional regulation of various cellular processes, including development, differentiation, and all aspects of cancer biology. Rapid-onset T-cell lymphoma of chickens, namely Marek’s disease (MD, induced by Gallid alphaherpesvirus 2 (GaHV2, could provide an ideal natural animal model for herpesvirus-related cancer research. GaHV2 encodes 26 mature miRNAs derived from 14 precursors assembled in three distinct gene clusters in the viral genome. One of the most highly expressed GaHV2 miRNAs, miR-M4-5p, shows high sequence similarity to the cellular miR-155 and the miR-K12-11 encoded by Kaposi’s sarcoma-associated herpesvirus, particularly in the miRNA “seed region.” As with miR-K12-11, miR-M4-5p shares a common set of host and viral target genes with miR-155, suggesting that they may target the same regulatory cellular networks; however, differences in regulatory function between miR-155 and miR-M4-5p may distinguish non-viral and viral mediated tumorigenesis. In this review, we focus on the functions of miR-M4-5p as the viral ortholog of miR-155 to explore how the virus mimics a host pathway to benefit the viral life cycle and trigger virus-induced tumorigenesis.

  14. A prospective study of the effect of pregnancy on CD4 counts and plasma HIV-1 RNA concentrations of antiretroviral-naive HIV-1-infected women.

    Science.gov (United States)

    Heffron, Renee; Donnell, Deborah; Kiarie, James; Rees, Helen; Ngure, Kenneth; Mugo, Nelly; Were, Edwin; Celum, Connie; Baeten, Jared M

    2014-02-01

    In HIV-1-infected women, CD4 count declines occur during pregnancy, which has been attributed to hemodilution. However, for women who have not initiated antiretroviral therapy, it is unclear if CD4 declines are sustained beyond pregnancy and accompanied by increased viral levels, which could indicate an effect of pregnancy on accelerating HIV-1 disease progression. In a prospective study among 2269 HIV-1-infected antiretroviral therapy-naive women from 7 African countries, we examined the effect of pregnancy on HIV-1 disease progression. We used linear mixed models to compare CD4 counts and plasma HIV-1 RNA concentrations between pregnant, postpartum, and nonpregnant periods. Women contributed 3270 person-years of follow-up, during which time 476 women became pregnant. In adjusted analysis, CD4 counts were an average of 56 (95% confidence interval: 39 to 73) cells/mm lower during pregnant compared with nonpregnant periods and 70 (95% confidence interval: 53 to 88) cells/mm lower during pregnant compared with postpartum periods; these results were consistent when restricted to the subgroup of women who became pregnant. Plasma HIV-1 RNA concentrations were not different between pregnant and nonpregnant periods (P = 0.9) or pregnant and postpartum periods (P = 0.3). Neither CD4 counts nor plasma HIV-1 RNA levels were significantly different in postpartum compared with nonpregnant periods. CD4 count declines among HIV-1-infected women during pregnancy are temporary and not sustained in postpartum periods. Pregnancy does not have a short-term impact on plasma HIV-1 RNA concentrations.

  15. A prospective study of the effect of pregnancy on CD4 counts and plasma HIV-1 RNA concentrations of antiretroviral-naive HIV-1 infected women

    Science.gov (United States)

    Heffron, Renee; Donnell, Deborah; Kiarie, James; Rees, Helen; Ngure, Kenneth; Mugo, Nelly; Were, Edwin; Celum, Connie; Baeten, Jared M.

    2014-01-01

    Background In HIV-1 infected women, CD4 count declines occur during pregnancy, which has been attributed to hemodilution. However, for women who have not initiated antiretroviral therapy (ART), it is unclear if CD4 declines are sustained beyond pregnancy and accompanied by increased viral levels, which could indicate an effect of pregnancy on accelerating HIV-1 disease progression. Methods In a prospective study among 2269 HIV-1 infected ART-naïve women from 7 African countries, we examined the effect of pregnancy on HIV-1 disease progression. We used linear mixed models to compare CD4 counts and plasma HIV-1 RNA concentrations between pregnant, postpartum and non-pregnant periods. Results Women contributed 3270 person-years of follow-up, during which time 476 women became pregnant. In adjusted analysis, CD4 counts were an average of 56 (95% CI 39-73) cells/mm3 lower during pregnant compared to non-pregnant periods and 70 (95% CI 53-88) cells/mm3 lower during pregnant compared to postpartum periods; these results were consistent when restricted to the subgroup of women who became pregnant. Plasma HIV-1 RNA concentrations were not different between pregnant and non-pregnant periods (p=0.9) or pregnant and postpartum periods (p=0.3). Neither CD4 counts nor plasma HIV-1 RNA levels were significantly different in postpartum compared to non-pregnant periods. Conclusion CD4 count declines among HIV-1 infected women during pregnancy are temporary and not sustained in postpartum periods. Pregnancy does not have a short term impact on plasma HIV-1 RNA concentrations. PMID:24442226

  16. Viral RNA-Unprimed Rig-I Restrains Stat3 Activation in the Modulation of Regulatory T Cell/Th17 Cell Balance.

    Science.gov (United States)

    Yang, Hui; Guo, He-Zhou; Li, Xian-Yang; Lin, Jian; Zhang, Wu; Zhao, Jun-Mei; Zhang, Hong-Xin; Chen, Sai-Juan; Chen, Zhu; Zhu, Jiang

    2017-07-01

    Innate immunity activation by viral RNA-primed retinoid acid inducible gene-I (Rig-I) in CD4 + T cells antagonizes TGFβ signaling to suppress the differentiation of regulatory T cells (Tregs). However, how viral RNA-unliganded Rig-I (apo-Rig-I) modulates Treg generation remains unclear. In this article, we show that, in the absence of viral infection, Treg differentiation of Rig-I -/- CD4 + T cells was compromised, in the presence of increased generation of Th17 cells and overactivation of Stat3, a critical regulator tilting the Treg/Th17 cell balance. Mechanistically, apo-Rig-I physically associates with Stat3, thereby inhibiting Jak1's association with Stat3 while facilitating Shp2's association to inhibit p-Stat3 levels. Interestingly, inhibition of Stat3 ameliorates the Treg/Th17 imbalance and the colitis observed in Rig-I -/- mice. Collectively, these results uncover an independent functional contribution of the apo-Rig-I/Stat3 interaction in the maintenance of Treg/Th17 cell balance. Copyright © 2017 by The American Association of Immunologists, Inc.

  17. Mal de Río Cuarto Virus Infection Triggers the Production of Distinctive Viral-Derived siRNA Profiles in Wheat and Its Planthopper Vector.

    Science.gov (United States)

    de Haro, Luis A; Dumón, Analía D; Mattio, María F; Argüello Caro, Evangelina Beatriz; Llauger, Gabriela; Zavallo, Diego; Blanc, Hervé; Mongelli, Vanesa C; Truol, Graciela; Saleh, María-Carla; Asurmendi, Sebastián; Del Vas, Mariana

    2017-01-01

    Plant reoviruses are able to multiply in gramineae plants and delphacid vectors encountering different defense strategies with unique features. This study aims to comparatively assess alterations of small RNA (sRNA) populations in both hosts upon virus infection. For this purpose, we characterized the sRNA profiles of wheat and planthopper vectors infected by Mal de Río Cuarto virus (MRCV, Fijivirus, Reoviridae ) and quantified virus genome segments by quantitative reverse transcription PCR We provide evidence that plant and insect silencing machineries differentially recognize the viral genome, thus giving rise to distinct profiles of virus-derived small interfering RNAs (vsiRNAs). In plants, most of the virus genome segments were targeted preferentially within their upstream sequences and vsiRNAs mapped with higher density to the smaller genome segments than to the medium or larger ones. This tendency, however, was not observed in insects. In both hosts, vsiRNAs were equally derived from sense and antisense RNA strands and the differences in vsiRNAs accumulation did not correlate with mRNAs accumulation. We also established that the piwi-interacting RNA (piRNA) pathway was active in the delphacid vector but, contrary to what is observed in virus-infected mosquitoes, virus-specific piRNAs were not detected. This work contributes to the understanding of the silencing response in insect and plant hosts.

  18. Abnormal levels of expression of plasma microRNA-33 in patients with psoriasis.

    Science.gov (United States)

    García-Rodríguez, S; Arias-Santiago, S; Orgaz-Molina, J; Magro-Checa, C; Valenzuela, I; Navarro, P; Naranjo-Sintes, R; Sancho, J; Zubiaur, M

    2014-06-01

    Circulating microRNAs (miRNA) are involved in the posttranscriptional regulation of genes associated with lipid metabolism (miRNA-33) and vascular function and angiogenesis (miRNA-126). The objective of this exploratory study was to measure plasma levels of miRNA-33 and miRNA-126 in patients with plaque psoriasis and evaluate their association with clinical parameters. We studied 11 patients with plaque psoriasis. The median Psoriasis Area Severity Index (PASI) was 13 (interquartile range [IQR], 9-14) and body surface area involvement was 12 (IQR, 11-15). Eleven healthy controls matched for age and sex were also included. We analyzed cardiovascular risk factors and subclinical carotid atheromatosis. Plasma miRNAs were evaluated using quantitative real-time polymerase chain reaction. Carotid intima-media thickness was greater in patients (0.57mm; IQR, 0.54-0.61; n=11) than in controls (0.50mm; IQR, 0.48-0.54; data available for 9 controls) (P=.0055, Mann-Whitney). Expression of miRNA-33 in patients (5.34; IQR, 3.12-7.96; n=11) was significantly higher than in controls (2.33; IQR, 1.71-2.84; only detected in 7 of 11 controls) (P=.0049, Wilcoxon signed rank). No differences in miRNA-126 levels were observed between patients and controls. In patients (n=11), we observed a positive correlation between miRNA-33 and insulin levels (r=0.7289, P=.0109) and a negative correlation between miRNA-126 and carotid intima-media thickness (r=-0.6181, P=.0426). In psoriasis patients plasma levels of lipid and glucose metabolism-related miRNA-33 are increased and correlated with insulin. The study of circulating miRNA-33 in psoriasis may provide new insights about the associated systemic inflammatory abnormalities. Copyright © 2013 Elsevier España, S.L. and AEDV. All rights reserved.

  19. Comparison of EBV DNA viral load in whole blood, plasma, B-cells and B-cell culture supernatant.

    Science.gov (United States)

    Ouedraogo, David Eric; Bollore, Karine; Viljoen, Johannes; Foulongne, Vincent; Reynes, Jacques; Cartron, Guillaume; Vendrell, Jean-Pierre; Van de Perre, Philippe; Tuaillon, Edouard

    2014-05-01

    Epstein-Barr virus (EBV) genome quantitation in whole blood is used widely for therapeutic monitoring of EBV-associated disorders in immunosuppressed individuals and in patients with EBV-associated lymphoma. However, the most appropriate biological material to be used for EBV DNA quantitation remains a subject of debate. This study compare the detection rate and levels of EBV DNA from whole blood, plasma, enriched B-cells, and B-cell short-term culture supernatant using quantitative real-time PCR. Samples were collected from 33 subjects with either HIV infection or B-cell lymphoma. Overall, EBV DNA was detected in 100% of enriched B-cell samples, in 82% of B-cell culture supernatants, in 57% of plasma, and 42% of whole blood samples. A significant correlation for EBV viral load was found between enriched B-cell and B-cell culture supernatant material (ρ = 0.92; P cells (ρ = -0.02; P = 0.89), whole blood and plasma (ρ = 0.24; P = 0.24), or enriched B-cells and plasma (ρ = 0.08; P = 0.77). Testing of enriched B-cells appeared to be the most sensitive method for detection of EBV DNA as well as for exploration of the cellular reservoir. Quantitation of EBV DNA in plasma and B-cell culture supernatant may be of interest to assess EBV reactivation dynamics and response to treatment as well as to decipher EBV host-pathogen interactions in various clinical scenarios. © 2013 Wiley Periodicals, Inc.

  20. Ultra Structural Characterisation of Tetherin - a Protein Capable of Preventing Viral Release from the Plasma Membrane

    Directory of Open Access Journals (Sweden)

    Ravindra K. Gupta

    2010-04-01

    Full Text Available Tetherin is an antiviral restriction factor made by mammalian cells to protect them from viral infection. It prevents newly formed virus particles from leaving infected cells. Its antiviral mechanism appears to be remarkably uncomplicated. In 2 studies published in PLoS Pathogens electron microscopy is used to support the hypothesis that the tethers that link HIV-1 virions to tetherin expressing cells contain tetherin and are likely to contain tetherin alone. They also show that the HIV-1 encoded tetherin antagonist that is known to cause tetherin degradation, Vpu, serves to reduce the amount of tetherin in the particles thereby allowing their release.

  1. Distinct binding interactions of HIV-1 Gag to Psi and non-Psi RNAs: Implications for viral genomic RNA packaging

    OpenAIRE

    Webb, Joseph A.; Jones, Christopher P.; Parent, Leslie J.; Rouzina, Ioulia; Musier-Forsyth, Karin

    2013-01-01

    The mechanism underlying the selective packaging of genomic RNA into HIV-1 virions is not known. This paper provides important new biophysical insights into the nature of protein–RNA interactions responsible for HIV-1 genome packaging by quantifying the electrostatic and hydrophobic contributions to specific and nonspecific RNA.

  2. Detection of hepatitis C viral RNA sequences in fresh and paraffin-embedded liver biopsy specimens of non-A, non-B hepatitis patients

    NARCIS (Netherlands)

    Bresters, D.; Cuypers, H. T.; Reesink, H. W.; Chamuleau, R. A.; Schipper, M. E.; Boeser-Nunnink, B. D.; Lelie, P. N.; Jansen, P. L.

    1992-01-01

    In this study methods of HCV-RNA detection in fresh frozen and formalin-fixed, paraffin-embedded liver biopsies are described. Of 22 untreated chronic non-A, non-B hepatitis patients and 6 control patients, a plasma sample and part of a liver biopsy were freshly frozen for hepatitis C virus (HCV)

  3. Pre-storage centrifugation conditions have significant impact on measured microRNA levels in biobanked EDTA plasma samples

    DEFF Research Database (Denmark)

    Binderup, Helle Glud; Houlind, Kim; Madsen, Jonna Skov

    2016-01-01

    in platelets this may partly be explained by residual platelets in the plasma samples used. When collecting fresh plasma samples, it is possible to produce cell-free/platelet-poor plasma by centrifugation. In this study, we systematically investigated whether biobanked EDTA plasma samples could be processed...... to be suitable for miRNA analysis. Materials and methods: Blood samples were collected from ten healthy volunteers and centrifuged to produce platelet-poor-plasma (PPP) and standard biobank plasma. After one week at -80 °C the biobanked EDTA plasma was re-centrifuged by different steps to remove residual...... platelets. Using RT-qPCR the levels of 14 miRNAs in the different plasma preparations were compared to that of PPP. Results: We were able to remove residual platelets from biobanked EDTA plasma by re-centrifugation of the thawed samples. Nevertheless, for most of the investigated miRNAs, the miRNA level...

  4. Plasma microRNA profiles in rat models of hepatocellular injury, cholestasis, and steatosis.

    Directory of Open Access Journals (Sweden)

    Yu Yamaura

    Full Text Available MicroRNAs (miRNAs are small RNA molecules that function to modulate the expression of target genes, playing important roles in a wide range of physiological and pathological processes. The miRNAs in body fluids have received considerable attention as potential biomarkers of various diseases. In this study, we compared the changes of the plasma miRNA expressions by acute liver injury (hepatocellular injury or cholestasis and chronic liver injury (steatosis, steatohepatitis and fibrosis using rat models made by the administration of chemicals or special diets. Using miRNA array analysis, we found that the levels of a large number of miRNAs (121-317 miRNAs were increased over 2-fold and the levels of a small number of miRNAs (6-35 miRNAs were decreased below 0.5-fold in all models except in a model of cholestasis caused by bile duct ligation. Interestingly, the expression profiles were different between the models, and the hierarchical clustering analysis discriminated between the acute and chronic liver injuries. In addition, miRNAs whose expressions were typically changed in each type of liver injury could be specified. It is notable that, in acute liver injury models, the plasma level of miR-122, the most abundant miRNA in the liver, was more quickly and dramatically increased than the plasma aminotransferase level, reflecting the extent of hepatocellular injury. This study demonstrated that the plasma miRNA profiles could reflect the types of liver injury (e.g. acute/chronic liver injury or hepatocellular injury/cholestasis/steatosis/steatohepatitis/fibrosis and identified the miRNAs that could be specific and sensitive biomarkers of liver injury.

  5. MicroRNA-134 as a potential plasma biomarker for the diagnosis of acute pulmonary embolism

    Directory of Open Access Journals (Sweden)

    Liu Yi

    2011-09-01

    Full Text Available Abstract Background Acute pulmonary embolism (APE remains a diagnostic challenge due to a variable clinical presentation and the lack of a reliable screening tool. MicroRNAs (miRNAs regulate gene expression in a wide range of pathophysiologic processes. Circulating miRNAs are emerging biomarkers in heart failure, type 2 diabetes and other disease states; however, using plasma miRNAs as biomarkers for the diagnosis of APE is still unknown. Methods Thirty-two APE patients, 32 healthy controls, and 22 non-APE patients (reported dyspnea, chest pain, or cough were enrolled in this study. The TaqMan miRNA microarray was used to identify dysregulated miRNAs in the plasma of APE patients. The TaqMan-based miRNA quantitative real-time reverse transcription polymerase chain reactions were used to validate the dysregulated miRNAs. The receiver-operator characteristic (ROC curve analysis was conducted to evaluate the diagnostic accuracy of the miRNA identified as the candidate biomarker. Results Plasma miRNA-134 (miR-134 level was significantly higher in the APE patients than in the healthy controls or non-APE patients. The ROC curve showed that plasma miR-134 was a specific diagnostic predictor of APE with an area under the curve of 0.833 (95% confidence interval, 0.737 to 0.929; P Conclusions Our findings indicated that plasma miR-134 could be an important biomarker for the diagnosis of APE. Because of this finding, large-scale investigations are urgently needed to pave the way from basic research to clinical utilization.

  6. Down-regulation of human endogenous retrovirus type K (HERV-K) viral env RNA in pancreatic cancer cells decreases cell proliferation and tumor growth

    Science.gov (United States)

    Li, Ming; Radvanyi, Laszlo; Yin, Bingnan; Li, Jia; Chivukula, Raghavender; Lin, Kevin; Lu, Yue; Shen, JianJun; Chang, David Z.; Li, Donghui; Johanning, Gary L.; Wang-Johanning, Feng

    2017-01-01

    Purpose We investigated the role of the human endogenous retrovirus type K (HERV-K) envelope (env) gene in pancreatic cancer (PC). Experimental Design shRNA was employed to knockdown (KD) the expression of HERV-K in PC cells. Results HERV-K env expression was detected in seven PC cell lines and in 80% of PC patient biopsies, but not in two normal pancreatic cell lines or uninvolved normal tissues. A new HERV-K splice variant was discovered in several PC cell lines. RT activity and virus-like particles were observed in culture media supernatant obtained from Panc-1 and Panc-2 cells. HERV-K viral RNA levels and anti-HERV-K antibody titers were significantly higher in PC patient sera (N=106) than in normal donor sera (N=40). Importantly, the in vitro and in vivo growth rates of three PC cell lines were significantly reduced after HERV-K KD by shRNA targeting HERV-K env, and there was reduced metastasis to lung after treatment. RNA-seq results revealed changes in gene expression after HERV-K env KD, including RAS and TP53. Furthermore, downregulation of HERV-K Env protein expression by shRNA also resulted in decreased expression of RAS, p-ERK, p-RSK, and p-AKT in several PC cells or tumors. Conclusion These results demonstrate that HERV-K influences signal transduction via the RAS-ERK-RSK pathway in PC. Our data highlight the potentially important role of HERV-K in tumorigenesis and progression of PC, and indicate that HERV-K viral proteins may be attractive biomarkers and/or tumor-associated antigens, as well as potentially useful targets for detection, diagnosis and immunotherapy of PC. PMID:28679769

  7. Immunological and viral determinants of dengue severity in hospitalized adults in Ha Noi, Viet Nam.

    Directory of Open Access Journals (Sweden)

    Annette Fox

    2011-03-01

    Full Text Available The relationships between the infecting dengue serotype, primary and secondary infection, viremia and dengue severity remain unclear. This cross-sectional study examined these interactions in adult patients hospitalized with dengue in Ha Noi.158 patients were enrolled between September 16 and November 11, 2008. Quantitative RT-PCR, serology and NS1 detection were used to confirm dengue infection, determine the serotype and plasma viral RNA concentration, and categorize infections as primary or secondary. 130 (82% were laboratory confirmed. Serology was consistent with primary and secondary infection in 34% and 61%, respectively. The infecting serotype was DENV-1 in 42 (32%, DENV-2 in 39 (30% and unknown in 49 (38%. Secondary infection was more common in DENV-2 infections (79% compared to DENV-1 (36%, p<0.001. The proportion that developed dengue haemorrhagic fever (DHF was 32% for secondary infection compared to 18% for primary infection (p = 0.14, and 26% for DENV-1 compared to 28% for DENV-2. The time until NS1 and plasma viral RNA were undetectable was shorter for DENV-2 compared to DENV-1 (p≤0.001 and plasma viral RNA concentration on day 5 was higher for DENV-1 (p = 0.03. Plasma viral RNA concentration was higher in secondary infection on day 5 of illness (p = 0.046. We didn't find an association between plasma viral RNA concentration and clinical severity.Dengue is emerging as a major public health problem in Ha Noi. DENV-1 and DENV-2 were the prevalent serotypes with similar numbers and clinical presentation. Secondary infection may be more common amongst DENV-2 than DENV-1 infections because DENV-2 infections resulted in lower plasma viral RNA concentrations and viral RNA concentrations were higher in secondary infection. The drivers of dengue emergence in northern Viet Nam need to be elucidated and public health measures instituted.

  8. F-Specific RNA Bacteriophages, Especially Members of Subgroup II, Should Be Reconsidered as Good Indicators of Viral Pollution of Oysters.

    Science.gov (United States)

    Hartard, C; Leclerc, M; Rivet, R; Maul, A; Loutreul, J; Banas, S; Boudaud, N; Gantzer, C

    2018-01-01

    Norovirus (NoV) is the leading cause of gastroenteritis outbreaks linked to oyster consumption. In this study, we investigated the potential of F-specific RNA bacteriophages (FRNAPH) as indicators of viral contamination in oysters by focusing especially on FRNAPH subgroup II (FRNAPH-II). These viral indicators have been neglected because their behavior is sometimes different from that of NoV in shellfish, especially during the depuration processes usually performed before marketing. However, a significant bias needs to be taken into account. This bias is that, in the absence of routine culture methods, NoV is targeted by genome detection, while the presence of FRNAPH is usually investigated by isolation of infectious particles. In this study, by targeting both viruses using genome detection, a significant correlation between the presence of FRNAPH-II and that of NoV in shellfish collected from various European harvesting areas impacted by fecal pollution was observed. Moreover, during their depuration, while the long period of persistence of NoV was confirmed, a similar or even longer period of persistence of the FRNAPH-II genome, which was over 30 days, was observed. Such a striking genome persistence calls into question the relevance of molecular methods for assessing viral hazards. Targeting the same virus (i.e., FRNAPH-II) by culture and genome detection in specimens from harvesting areas as well as during depuration, we concluded that the presence of genomes in shellfish does not provide any information on the presence of the corresponding infectious particles. In view of these results, infectious FRNAPH detection should be reconsidered as a valuable indicator in oysters, and its potential for use in assessing viral hazard needs to be investigated. IMPORTANCE This work brings new data about the behavior of viruses in shellfish, as well as about the relevance of molecular methods for their detection and evaluation of the viral hazard. First, a strong

  9. Phosphorylation of the human respiratory syncytial virus P protein mediates M2-2 regulation of viral RNA synthesis, a process that involves two P proteins.

    Science.gov (United States)

    Asenjo, Ana; Villanueva, Nieves

    2016-01-04

    The M2-2 protein regulates the balance between human respiratory syncytial virus (HRSV) transcription and replication. Here it is shown that M2-2 mediated transcriptional inhibition is managed through P protein phosphorylation. Transcription inhibition by M2-2 of the HRSV based minigenome pRSVluc, required P protein phosphorylation at serines (S) in positions 116, 117, 119 and increased inhibition is observed if S232 or S237 is also phosphorylated. Phosphorylation of these residues is required for viral particle egression from infected cells. Viral RNA synthesis complementation assays between P protein variants, suggest that two types of P proteins participate in the process as components of RNA dependent RNA polymerase (RdRp). Type I is only functional when, as a homotetramer, it is bound to N and L proteins through residues 203-241. Type II is functionally independent of these interactions and binds to N protein at a region outside residues 232-241. P protein type I phosphorylation at S116, S117 and S119, did not affect the activity of RdRp but this phosphorylation in type II avoids its interaction with N protein and impairs RdRp functionality for transcription and replication. Structural changes in the RdRp, mediated by phosphorylation turnover at the indicated residues, in the two types of P proteins, may result in a fine adjustment, late in the infectious cycle, of transcription, replication and progression in the morphogenetic process that ends in egression of the viral particles from infected cells. Copyright © 2015 Elsevier B.V. All rights reserved.

  10. Identification of sequences in herpes simplex virus type 1 ICP22 that influence RNA polymerase II modification and viral late gene expression.

    Science.gov (United States)

    Bastian, Thomas W; Rice, Stephen A

    2009-01-01

    Previous studies have shown that the herpes simplex virus type 1 (HSV-1) immediate-early protein ICP22 alters the phosphorylation of the host cell RNA polymerase II (Pol II) during viral infection. In this study, we have engineered several ICP22 plasmid and virus mutants in order to map the ICP22 sequences that are involved in this function. We identify a region in the C-terminal half of ICP22 (residues 240 to 340) that is critical for Pol II modification and further show that the N-terminal half of the protein (residues 1 to 239) is not required. However, immunofluorescence analysis indicates that the N-terminal half of ICP22 is needed for its localization to nuclear body structures. These results demonstrate that ICP22's effects on Pol II do not require that it accumulate in nuclear bodies. As ICP22 is known to enhance viral late gene expression during infection of certain cultured cells, including human embryonic lung (HEL) cells, we used our engineered viral mutants to map this function of ICP22. It was found that mutations in both the N- and C-terminal halves of ICP22 result in similar defects in viral late gene expression and growth in HEL cells, despite having distinctly different effects on Pol II. Thus, our results genetically uncouple ICP22's effects on Pol II from its effects on viral late gene expression. This suggests that these two functions of ICP22 may be due to distinct activities of the protein.

  11. Viral unmasking of cellular 5S rRNA pseudogene transcripts induces RIG-I-mediated immunity.

    Science.gov (United States)

    Chiang, Jessica J; Sparrer, Konstantin M J; van Gent, Michiel; Lässig, Charlotte; Huang, Teng; Osterrieder, Nikolaus; Hopfner, Karl-Peter; Gack, Michaela U

    2018-01-01

    The sensor RIG-I detects double-stranded RNA derived from RNA viruses. Although RIG-I is also known to have a role in the antiviral response to DNA viruses, physiological RNA species recognized by RIG-I during infection with a DNA virus are largely unknown. Using next-generation RNA sequencing (RNAseq), we found that host-derived RNAs, most prominently 5S ribosomal RNA pseudogene 141 (RNA5SP141), bound to RIG-I during infection with herpes simplex virus 1 (HSV-1). Infection with HSV-1 induced relocalization of RNA5SP141 from the nucleus to the cytoplasm, and virus-induced shutoff of host protein synthesis downregulated the abundance of RNA5SP141-interacting proteins, which allowed RNA5SP141 to bind RIG-I and induce the expression of type I interferons. Silencing of RNA5SP141 strongly dampened the antiviral response to HSV-1 and the related virus Epstein-Barr virus (EBV), as well as influenza A virus (IAV). Our findings reveal that antiviral immunity can be triggered by host RNAs that are unshielded following depletion of their respective binding proteins by the virus.

  12. Extracellular plasma RNA from colon cancer patients is confined in a vesicle-like structure and is mRNA-enriched

    Science.gov (United States)

    García, José Miguel; García, Vanesa; Peña, Cristina; Domínguez, Gemma; Silva, Javier; Diaz, Raquel; Espinosa, Pablo; Citores, Maria Jesús; Collado, Manuel; Bonilla, Félix

    2008-01-01

    Little is yet known about the origin and protective mechanism of free nucleic acids in plasma. We investigated the possibility of these free nucleic acids being particle associated. Plasma samples from colon cancer patients and cell culture media were subjected to various antibody incubations, ultracentrifugation, and RNA extraction protocols for total RNA, epithelial RNA, and mRNA. Flow cytometry using a Ber-EP4 antibody and confocal laser microscopy after staining with propidium iodide were also performed. mRNA levels of the LISCH7 and SDHA genes were determined in cells and in culture media. Ber-EP4 antibody and polystyrene beads coated with oligo dT sequences were employed. We observed that, after incubation, total RNA and mRNA were always detected after membrane digestion, and that epithelial RNA was detected before this procedure. In ultracentrifugation, mRNA was caught in the supernatant only if a former lysis mediated or in the pellet if there was no previous digestion. Flow cytometry determinations showed that antibody-coated microbeads keep acellular structures bearing epithelial antigens apart. Confocal laser microscopy made 1- to 2-μm-diameter particles perceptible in the vicinity of magnetic polystyrene beads. Relevant differences were observed between mRNA of cells and culture media, as there was a considerable difference in LISCH7 mRNA levels between HT29 and IMR90 cell co-cultures and their culture media. Our results support the view that extracellular RNA found in plasma from cancer patients circulates in association with or is protected in a multiparticle complex, and that an active release mechanism by tumor cells may be a possible origin. PMID:18456845

  13. Rescue of foot-and-mouth disease viruses that are pathogenic for cattle from preserved viral RNA samples

    DEFF Research Database (Denmark)

    Belsham, Graham; Jamal, Syed Muhammad; Tjørnehøj, Kirsten

    2011-01-01

    Background: Foot and mouth disease is an economically important disease of cloven-hoofed animals including cattle, sheep and pigs. It is caused by a picornavirus, foot-and-mouth disease virus (FMDV), which has a positive sense RNA genome which, when introduced into cells, can initiate virus...... replication. Principal Findings: A system has been developed to rescue infectious FMDV from RNA preparations generated from clinical samples obtained under experimental conditions and then applied to samples collected in the ‘‘field’’. Clinical samples from suspect cases of foot-and-mouth disease (FMD) were...... obtained from within Pakistan and Afghanistan. The samples were treated to preserve the RNA and then transported to National Veterinary Institute, Lindholm, Denmark. Following RNA extraction, FMDV RNA was quantified by real-time RT-PCR and samples containing significant levels of FMDV RNA were introduced...

  14. Modification of picornavirus genomic RNA using 'click' chemistry shows that unlinking of the VPg peptide is dispensable for translation and replication of the incoming viral RNA

    NARCIS (Netherlands)

    Langereis, Martijn A|info:eu-repo/dai/nl/304823597; Feng, Qian; Nelissen, Frank H T; Virgen-Slane, Richard; van der Heden van Noort, Gerbrand J; Maciejewski, Sonia; Filippov, Dmitri V; Semler, Bert L; van Delft, Floris L; van Kuppeveld, Frank J M|info:eu-repo/dai/nl/156614723

    Picornaviruses constitute a large group of viruses comprising medically and economically important pathogens such as poliovirus, coxsackievirus, rhinovirus, enterovirus 71 and foot-and-mouth disease virus. A unique characteristic of these viruses is the use of a viral peptide (VPg) as primer for

  15. The Andes hantavirus NSs protein is expressed from the viral small mRNA by a leaky scanning mechanism.

    Science.gov (United States)

    Vera-Otarola, Jorge; Solis, Loretto; Soto-Rifo, Ricardo; Ricci, Emiliano P; Pino, Karla; Tischler, Nicole D; Ohlmann, Théophile; Darlix, Jean-Luc; López-Lastra, Marcelo

    2012-02-01

    The small mRNA (SmRNA) of all Bunyaviridae encodes the nucleocapsid (N) protein. In 4 out of 5 genera in the Bunyaviridae, the smRNA encodes an additional nonstructural protein denominated NSs. In this study, we show that Andes hantavirus (ANDV) SmRNA encodes an NSs protein. Data show that the NSs protein is expressed in the context of an ANDV infection. Additionally, our results suggest that translation initiation from the NSs initiation codon is mediated by ribosomal subunits that have bypassed the upstream N protein initiation codon through a leaky scanning mechanism.

  16. Evaluation of microRNA stability in plasma and serum from healthy dogs

    DEFF Research Database (Denmark)

    Enelund, Lars; Nielsen, Lise Nikolic; Cirera, Susanna

    2017-01-01

    . METHODS: The levels of four microRNAs (cfa-let-7a, cfa-miR-16, cfa-miR-23a and cfa-miR-26a) known to be stably expressed from other canine studies, have been measured by real-time quantitative PCR. RESULTS: MicroRNA levels were found sufficiently stable for gene profiling in serum- and plasma stored...

  17. Paper-Based MicroRNA Expression Profiling from Plasma and Circulating Tumor Cells.

    Science.gov (United States)

    Leong, Sai Mun; Tan, Karen Mei-Ling; Chua, Hui Wen; Huang, Mo-Chao; Cheong, Wai Chye; Li, Mo-Huang; Tucker, Steven; Koay, Evelyn Siew-Chuan

    2017-03-01

    Molecular characterization of circulating tumor cells (CTCs) holds great promise for monitoring metastatic progression and characterizing metastatic disease. However, leukocyte and red blood cell contamination of routinely isolated CTCs makes CTC-specific molecular characterization extremely challenging. Here we report the use of a paper-based medium for efficient extraction of microRNAs (miRNAs) from limited amounts of biological samples such as rare CTCs harvested from cancer patient blood. Specifically, we devised a workflow involving the use of Flinders Technology Associates (FTA) ® Elute Card with a digital PCR-inspired "partitioning" method to extract and purify miRNAs from plasma and CTCs. We demonstrated the sensitivity of this method to detect miRNA expression from as few as 3 cancer cells spiked into human blood. Using this method, background miRNA expression was excluded from contaminating blood cells, and CTC-specific miRNA expression profiles were derived from breast and colorectal cancer patients. Plasma separated out during purification of CTCs could likewise be processed using the same paper-based method for miRNA detection, thereby maximizing the amount of patient-specific information that can be derived from a single blood draw. Overall, this paper-based extraction method enables an efficient, cost-effective workflow for maximized recovery of small RNAs from limited biological samples for downstream molecular analyses. © 2016 American Association for Clinical Chemistry.

  18. Transmissible Gastroenteritis Coronavirus Genome Packaging Signal Is Located at the 5′ End of the Genome and Promotes Viral RNA Incorporation into Virions in a Replication-Independent Process

    Science.gov (United States)

    Morales, Lucia; Mateos-Gomez, Pedro A.; Capiscol, Carmen; del Palacio, Lorena; Sola, Isabel

    2013-01-01

    Preferential RNA packaging in coronaviruses involves the recognition of viral genomic RNA, a crucial process for viral particle morphogenesis mediated by RNA-specific sequences, known as packaging signals. An essential packaging signal component of transmissible gastroenteritis coronavirus (TGEV) has been further delimited to the first 598 nucleotides (nt) from the 5′ end of its RNA genome, by using recombinant viruses transcribing subgenomic mRNA that included potential packaging signals. The integrity of the entire sequence domain was necessary because deletion of any of the five structural motifs defined within this region abrogated specific packaging of this viral RNA. One of these RNA motifs was the stem-loop SL5, a highly conserved motif in coronaviruses located at nucleotide positions 106 to 136. Partial deletion or point mutations within this motif also abrogated packaging. Using TGEV-derived defective minigenomes replicated in trans by a helper virus, we have shown that TGEV RNA packaging is a replication-independent process. Furthermore, the last 494 nt of the genomic 3′ end were not essential for packaging, although this region increased packaging efficiency. TGEV RNA sequences identified as necessary for viral genome packaging were not sufficient to direct packaging of a heterologous sequence derived from the green fluorescent protein gene. These results indicated that TGEV genome packaging is a complex process involving many factors in addition to the identified RNA packaging signal. The identification of well-defined RNA motifs within the TGEV RNA genome that are essential for packaging will be useful for designing packaging-deficient biosafe coronavirus-derived vectors and providing new targets for antiviral therapies. PMID:23966403

  19. Enterovirus 71 encephalomyelitis and Japanese encephalitis can be distinguished by topographic distribution of inflammation and specific intraneuronal detection of viral antigen and RNA.

    Science.gov (United States)

    Wong, K T; Ng, K Y; Ong, K C; Ng, W F; Shankar, S K; Mahadevan, A; Radotra, B; Su, I J; Lau, G; Ling, A E; Chan, K P; Macorelles, P; Vallet, S; Cardosa, M J; Desai, A; Ravi, V; Nagata, N; Shimizu, H; Takasaki, T

    2012-08-01

    To investigate if two important epidemic viral encephalitis in children, Enterovirus 71 (EV71) encephalomyelitis and Japanese encephalitis (JE) whose clinical and pathological features may be nonspecific and overlapping, could be distinguished. Tissue sections from the central nervous system of infected cases were examined by light microscopy, immunohistochemistry and in situ hybridization. All 13 cases of EV71 encephalomyelitis collected from Asia and France invariably showed stereotyped distribution of inflammation in the spinal cord, brainstem, hypothalamus, cerebellar dentate nucleus and, to a lesser extent, cerebral cortex and meninges. Anterior pons, corpus striatum, thalamus, temporal lobe, hippocampus and cerebellar cortex were always uninflamed. In contrast, the eight JE cases studied showed inflammation involving most neuronal areas of the central nervous system, including the areas that were uninflamed in EV71 encephalomyelitis. Lesions in both infections were nonspecific, consisting of perivascular and parenchymal infiltration by inflammatory cells, oedematous/necrolytic areas, microglial nodules and neuronophagia. Viral inclusions were absent. Immunohistochemistry and in situ hybridization assays were useful to identify the causative virus, localizing viral antigens and RNA, respectively, almost exclusively to neurones. The stereotyped distribution of inflammatory lesions in EV71 encephalomyelitis appears to be very useful to help distinguish it from JE. © 2011 The Authors. Neuropathology and Applied Neurobiology © 2011 British Neuropathological Society.

  20. Dynamics of viral replication in blood and lymphoid tissues during SIVmac251 infection of macaques

    Directory of Open Access Journals (Sweden)

    Mannioui Abdelkrim

    2009-01-01

    Full Text Available Abstract Background Extensive studies of primary infection are crucial to our understanding of the course of HIV disease. In SIV-infected macaques, a model closely mimicking HIV pathogenesis, we used a combination of three markers -- viral RNA, 2LTR circles and viral DNA -- to evaluate viral replication and dissemination simultaneously in blood, secondary lymphoid tissues, and the gut during primary and chronic infections. Subsequent viral compartmentalization in the main target cells of the virus in peripheral blood during the chronic phase of infection was evaluated by cell sorting and viral quantification with the three markers studied. Results The evolutions of viral RNA, 2LTR circles and DNA levels were correlated in a given tissue during primary and early chronic infection. The decrease in plasma viral load principally reflects a large decrease in viral replication in gut-associated lymphoid tissue (GALT, with viral RNA and DNA levels remaining stable in the spleen and peripheral lymph nodes. Later, during chronic infection, a progressive depletion of central memory CD4+ T cells from the peripheral blood was observed, accompanied by high levels of viral replication in the cells of this subtype. The virus was also found to replicate at this point in the infection in naive CD4+ T cells. Viral RNA was frequently detected in monocytes, but no SIV replication appeared to occur in these cells, as no viral DNA or 2LTR circles were detected. Conclusion We demonstrated the persistence of viral replication and dissemination, mostly in secondary lymphoid tissues, during primary and early chronic infection. During chronic infection, the central memory CD4+ T cells were the major site of viral replication in peripheral blood, but viral replication also occurred in naive CD4+ T cells. The role of monocytes seemed to be limited to carrying the virus as a cargo because there was an observed lack of replication in these cells. These data may have important

  1. Glyceraldehyde-3-phosphate dehydrogenase (GAPDH interaction with 3' ends of Japanese encephalitis virus RNA and colocalization with the viral NS5 protein

    Directory of Open Access Journals (Sweden)

    Chou Shih-Jie

    2009-04-01

    Full Text Available Abstract Replication of the Japanese encephalitis virus (JEV genome depends on host factors for successfully completing their life cycles; to do this, host factors have been recruited and/or relocated to the site of viral replication. Glyceraldehyde-3-phosphate dehydrogenase (GAPDH, a cellular metabolic protein, was found to colocalize with viral RNA-dependent RNA polymerase (NS5 in JEV-infected cells. Subcellular fractionation further indicated that GAPDH remained relatively constant in the cytosol, while increasing at 12 to 24 hours postinfection (hpi and decreasing at 36 hpi in the nuclear fraction of infected cells. In contrast, the redistribution patterns of GAPDH were not observed in the uninfected cells. Co-immunoprecipitation of GAPDH and JEV NS5 protein revealed no direct protein-protein interaction; instead, GAPDH binds to the 3' termini of plus- and minus-strand RNAs of JEV by electrophoretic mobility shift assays. Accordingly, GAPDH binds to the minus strand more efficiently than to the plus strand of JEV RNAs. This study highlights the findings that infection of JEV changes subcellular localization of GAPDH suggesting that this metabolic enzyme may play a role in JEV replication.

  2. Trans-activation of the 5' to 3' viral DNA strand transfer by nucleocapsid protein during reverse transcription of HIV1 RNA.

    Science.gov (United States)

    Darlix, J L; Vincent, A; Gabus, C; de Rocquigny, H; Roques, B

    1993-08-01

    Two DNA strand transfer reactions take place during reverse transcription of the retroviral genome. The first transfer, that of the minus-strand strong stop DNA from the 5' end of the viral RNA to the 3' end, has been studied in vitro with two RNAs mimicking the 5' and 3' regions of the HIV1 genome and with nucleocapsid protein, NCp7, and reverse transcriptase. The results show that NCp7 strongly activates the 5' to 3' DNA strand transfer during reverse transcription while a basic peptide resembling NCp7 is inactive. Activation of the first transfer by several NCp7 derived peptides and the influence of the terminal redundancies (R) present at the 5' and 3' ends of HIV1 RNA were also examined. The first transfer is optimal in the presence of intact NCp7 and necessitates R on both the 5' and 3' RNAs. Sequencing of full length viral DNA products reveals approximately 40% misincorporations at the first nucleotide beyond the transfer point. If such base misincorporations occur during proviral DNA synthesis with possible homologous recombinations it may well contribute to the high level of genetic variability of HIV.

  3. Functional analysis of the cloverleaf-like structure in the 3' untranslated region of bamboo mosaic potexvirus RNA revealed dual roles in viral RNA replication and long distance movement

    International Nuclear Information System (INIS)

    Chen, I-H.; Meng Hsiao; Hsu, Y.-H.; Tsai, C.-H.

    2003-01-01

    The 3' untranslated region (UTR) of bamboo mosaic potexvirus (BaMV) RNA was identified to fold into a tertiary structure comprising a cloverleaf-like structure designated ABC domain followed by a major stem-loop D, which in turn is followed by a pseudoknot E and a poly(A) tail. The coat protein accumulation level of the mutant, BaMV40A/ΔABC, lacking ABC domain was just 15% that of wild-type when inoculated into protoplasts of Nicotiana benthamiana. This suggested that ABC domain might play an important role in BaMV RNA replication. To define the precise role of each of the three stem-loops of ABC domain in RNA replication, three mutants BaMV40B and C each lacking stem-loop A, B, and C, respectively, were created. Our results showed that accumulation of viral products of mutants BaMV40B and C were not as efficient as wild-type. On the contrary, level of accumulation of viral products of BaMVA was similar to that of wild-type in protoplasts and inoculated leaves. Interestingly, the accumulation of viral products was not as efficient as that of wild-type in systemic leaves, implying that stem-loop A is dispensable for replication, but signifies a role in systemic accumulation. Using UV cross-linking and competition experiments, it was demonstrated that the E. coli expressed helicase domain of BaMV ORF1 can preferentially interact with the ABC domain

  4. The predictive and prognostic potential of plasma telomerase reverse transcriptase (TERT) RNA in rectal cancer patients

    Science.gov (United States)

    Rampazzo, Enrica; Del Bianco, Paola; Bertorelle, Roberta; Boso, Caterina; Perin, Alessandro; Spiro, Giovanna; Bergamo, Francesca; Belluco, Claudio; Buonadonna, Angela; Palazzari, Elisa; Leonardi, Sara; De Paoli, Antonino; Pucciarelli, Salvatore; De Rossi, Anita

    2018-01-01

    Background: Preoperative chemoradiotherapy (CRT) followed by surgery is the standard care for locally advanced rectal cancer, but tumour response to CRT and disease outcome are variable. The current study aimed to investigate the effectiveness of plasma telomerase reverse transcriptase (TERT) levels in predicting tumour response and clinical outcome. Methods: 176 rectal cancer patients were included. Plasma samples were collected at baseline (before CRT=T0), 2 weeks after CRT was initiated (T1), post-CRT and before surgery (T2), and 4–8 months after surgery (T3) time points. Plasma TERT mRNA levels and total cell-free RNA were determined using real-time PCR. Results: Plasma levels of TERT were significantly lower at T2 (P<0.0001) in responders than in non-responders. Post-CRT TERT levels and the differences between pre- and post-CRT TERT levels independently predicted tumour response, and the prediction model had an area under curve of 0.80 (95% confidence interval (CI) 0.73–0.87). Multiple analysis demonstrated that patients with detectable TERT levels at T2 and T3 time points had a risk of disease progression 2.13 (95% CI 1.10–4.11)-fold and 4.55 (95% CI 1.48–13.95)-fold higher, respectively, than those with undetectable plasma TERT levels. Conclusions: Plasma TERT levels are independent markers of tumour response and are prognostic of disease progression in rectal cancer patients who undergo neoadjuvant therapy. PMID:29449673

  5. RNA.

    Science.gov (United States)

    Darnell, James E., Jr.

    1985-01-01

    Ribonucleic acid (RNA) converts genetic information into protein and usually must be processed to serve its function. RNA types, chemical structure, protein synthesis, translation, manufacture, and processing are discussed. Concludes that the first genes might have been spliced RNA and that humans might be closer than bacteria to primitive…

  6. First insight into the viral community of the cnidarian model metaorganism Aiptasia using RNA-Seq data

    KAUST Repository

    Brü wer, Jan D.; Voolstra, Christian R.

    2018-01-01

    of the globally threatened coral reef ecosystems. To gain first insight into viruses associated with the coral model system Aiptasia (sensu Exaiptasia pallida), we analyzed an existing RNA-Seq dataset of aposymbiotic, partially populated, and fully symbiotic

  7. Non-invasive aneuploidy detection using free fetal DNA and RNA in maternal plasma: recent progress and future possibilities.

    NARCIS (Netherlands)

    Go, A.T.; Vugt, J.M.G. van; Oudejans, C.B.

    2011-01-01

    BACKGROUND: Cell-free fetal DNA (cff DNA) and RNA can be detected in maternal plasma and used for non-invasive prenatal diagnostics. Recent technical advances have led to a drastic change in the clinical applicability and potential uses of free fetal DNA and RNA. This review summarizes the latest

  8. Rescue of foot-and-mouth disease viruses that are pathogenic for cattle from preserved viral RNA samples.

    Directory of Open Access Journals (Sweden)

    Graham J Belsham

    Full Text Available BACKGROUND: Foot and mouth disease is an economically important disease of cloven-hoofed animals including cattle, sheep and pigs. It is caused by a picornavirus, foot-and-mouth disease virus (FMDV, which has a positive sense RNA genome which, when introduced into cells, can initiate virus replication. PRINCIPAL FINDINGS: A system has been developed to rescue infectious FMDV from RNA preparations generated from clinical samples obtained under experimental conditions and then applied to samples collected in the "field". Clinical samples from suspect cases of foot-and-mouth disease (FMD were obtained from within Pakistan and Afghanistan. The samples were treated to preserve the RNA and then transported to National Veterinary Institute, Lindholm, Denmark. Following RNA extraction, FMDV RNA was quantified by real-time RT-PCR and samples containing significant levels of FMDV RNA were introduced into susceptible cells using electroporation. Progeny viruses were amplified in primary bovine thyroid cells and characterized using antigen ELISA and also by RT-PCR plus sequencing. FMD viruses of three different serotypes and multiple lineages have been successfully rescued from the RNA samples. Two of the rescued viruses (of serotype O and Asia 1 were inoculated into bull calves under high containment conditions. Acute clinical disease was observed in each case which spread rapidly from the inoculated calves to in-contact animals. Thus the rescued viruses were highly pathogenic. The availability of the rescued viruses enabled serotyping by antigen ELISA and facilitated genome sequencing. CONCLUSIONS: The procedure described here should improve the characterization of FMDVs circulating in countries where the disease is endemic and thus enhance disease control globally.

  9. Detection of potentially novel paramyxovirus and coronavirus viral RNA in bats and rats in the Mekong Delta region of southern Viet Nam.

    Science.gov (United States)

    Berto, A; Anh, P H; Carrique-Mas, J J; Simmonds, P; Van Cuong, N; Tue, N T; Van Dung, N; Woolhouse, M E; Smith, I; Marsh, G A; Bryant, J E; Thwaites, G E; Baker, S; Rabaa, M A

    2018-02-01

    Bats and rodents are being increasingly recognized as reservoirs of emerging zoonotic viruses. Various studies have investigated bat viruses in tropical regions, but to date there are no data regarding viruses with zoonotic potential that circulate in bat and rat populations in Viet Nam. To address this paucity of data, we sampled three bat farms and three wet markets trading in rat meat in the Mekong Delta region of southern Viet Nam. Faecal and urine samples were screened for the presence of RNA from paramyxoviruses, coronaviruses and filoviruses. Paramyxovirus RNA was detected in 4 of 248 (1%) and 11 of 222 (4.9%) bat faecal and urine samples, respectively. Coronavirus RNA was detected in 55 of 248 (22%) of bat faecal samples; filovirus RNA was not detected in any of the bat samples. Further, coronavirus RNA was detected in 12 of 270 (4.4%) of rat faecal samples; all samples tested negative for paramyxovirus. Phylogenetic analysis revealed that the bat paramyxoviruses and bat and rat coronaviruses were related to viruses circulating in bat and rodent populations globally, but showed no cross-species mixing of viruses between bat and rat populations within Viet Nam. Our study shows that potentially novel variants of paramyxoviruses and coronaviruses commonly circulate in bat and rat populations in Viet Nam. Further characterization of the viruses and additional human and animal surveillance is required to evaluate the likelihood of viral spillover and to assess whether these viruses pose a risk to human health. © 2017 The Authors. Zoonoses and Public Health Published by Blackwell Verlag GmbH.

  10. Mimic Phosphorylation of a βC1 Protein Encoded by TYLCCNB Impairs Its Functions as a Viral Suppressor of RNA Silencing and a Symptom Determinant.

    Science.gov (United States)

    Zhong, Xueting; Wang, Zhan Qi; Xiao, Ruyuan; Cao, Linge; Wang, Yaqin; Xie, Yan; Zhou, Xueping

    2017-08-15

    Phosphorylation of the βC1 protein encoded by the betasatellite of tomato yellow leaf curl China virus (TYLCCNB-βC1) by SNF1-related protein kinase 1 (SnRK1) plays a critical role in defense of host plants against geminivirus infection in Nicotiana benthamiana However, how phosphorylation of TYLCCNB-βC1 impacts its pathogenic functions during viral infection remains elusive. In this study, we identified two additional tyrosine residues in TYLCCNB-βC1 that are phosphorylated by SnRK1. The effects of TYLCCNB-βC1 phosphorylation on its functions as a viral suppressor of RNA silencing (VSR) and a symptom determinant were investigated via phosphorylation mimic mutants in N. benthamiana plants. Mutations that mimic phosphorylation of TYLCCNB-βC1 at tyrosine 5 and tyrosine 110 attenuated disease symptoms during viral infection. The phosphorylation mimics weakened the ability of TYLCCNB-βC1 to reverse transcriptional gene silencing and to suppress posttranscriptional gene silencing and abolished its interaction with N. benthamiana ASYMMETRIC LEAVES 1 in N. benthamiana leaves. The mimic phosphorylation of TYLCCNB-βC1 had no impact on its protein stability, subcellular localization, or self-association. Our data establish an inhibitory effect of phosphorylation of TYLCCNB-βC1 on its pathogenic functions as a VSR and a symptom determinant and provide a mechanistic explanation of how SnRK1 functions as a host defense factor. IMPORTANCE Tomato yellow leaf curl China virus (TYLCCNV), which causes a severe yellow leaf curl disease in China, is a monopartite geminivirus associated with the betasatellite (TYLCCNB). TYLCCNB encodes a single pathogenicity protein, βC1 (TYLCCNB-βC1), which functions as both a viral suppressor of RNA silencing (VSR) and a symptom determinant. Here, we show that mimicking phosphorylation of TYLCCNB-βC1 weakens its ability to reverse transcriptional gene silencing, to suppress posttranscriptional gene silencing, and to interact with N

  11. High-throughput sequencing of plasma microRNA in chronic fatigue syndrome/myalgic encephalomyelitis.

    Directory of Open Access Journals (Sweden)

    Ekua W Brenu

    Full Text Available BACKGROUND: MicroRNAs (miRNAs are known to regulate many biological processes and their dysregulation has been associated with a variety of diseases including Chronic Fatigue Syndrome/Myalgic Encephalomyelitis (CFS/ME. The recent discovery of stable and reproducible miRNA in plasma has raised the possibility that circulating miRNAs may serve as novel diagnostic markers. The objective of this study was to determine the role of plasma miRNA in CFS/ME. RESULTS: Using Illumina high-throughput sequencing we identified 19 miRNAs that were differentially expressed in the plasma of CFS/ME patients in comparison to non-fatigued controls. Following RT-qPCR analysis, we were able to confirm the significant up-regulation of three miRNAs (hsa-miR-127-3p, hsa-miR-142-5p and hsa-miR-143-3p in the CFS/ME patients. CONCLUSION: Our study is the first to identify circulating miRNAs from CFS/ME patients and also to confirm three differentially expressed circulating miRNAs in CFS/ME patients, providing a basis for further study to find useful CFS/ME biomarkers.

  12. High-Throughput Sequencing of Plasma MicroRNA in Chronic Fatigue Syndrome/Myalgic Encephalomyelitis

    Science.gov (United States)

    Brenu, Ekua W.; Ashton, Kevin J.; Batovska, Jana; Staines, Donald R.; Marshall-Gradisnik, Sonya M.

    2014-01-01

    Background MicroRNAs (miRNAs) are known to regulate many biological processes and their dysregulation has been associated with a variety of diseases including Chronic Fatigue Syndrome/Myalgic Encephalomyelitis (CFS/ME). The recent discovery of stable and reproducible miRNA in plasma has raised the possibility that circulating miRNAs may serve as novel diagnostic markers. The objective of this study was to determine the role of plasma miRNA in CFS/ME. Results Using Illumina high-throughput sequencing we identified 19 miRNAs that were differentially expressed in the plasma of CFS/ME patients in comparison to non-fatigued controls. Following RT-qPCR analysis, we were able to confirm the significant up-regulation of three miRNAs (hsa-miR-127-3p, hsa-miR-142-5p and hsa-miR-143-3p) in the CFS/ME patients. Conclusion Our study is the first to identify circulating miRNAs from CFS/ME patients and also to confirm three differentially expressed circulating miRNAs in CFS/ME patients, providing a basis for further study to find useful CFS/ME biomarkers. PMID:25238588

  13. Effects of a human plasma membrane-associated sialidase siRNA on prostate cancer invasion

    Energy Technology Data Exchange (ETDEWEB)

    Li, Xiaojie [Department of Pathophysiology, Prostate Diseases Prevention and Treatment Research Centre, Norman Bethune Medical School, Jilin University, Changchun (China); Taizhou Polytechnic College, Taizhou (China); Zhang, Ling; Shao, Yueting; Liang, Zuowen; Shao, Chen; Wang, Bo; Guo, Baofeng; Li, Na; Zhao, Xuejian [Department of Pathophysiology, Prostate Diseases Prevention and Treatment Research Centre, Norman Bethune Medical School, Jilin University, Changchun (China); Li, Yang, E-mail: lyang@jlu.edu.cn [Department of Pathophysiology, Prostate Diseases Prevention and Treatment Research Centre, Norman Bethune Medical School, Jilin University, Changchun (China); Xu, Deqi [Laboratory of Enteric and Sexually Transmitted Diseases, Center for Biologics Evaluation and Research, Food and Drug Administration, Bethesda, MD (United States)

    2011-12-16

    Highlights: Black-Right-Pointing-Pointer Neu3 is as one of the sialidases and regulates cell surface functions. Black-Right-Pointing-Pointer A Neu3-specific siRNA inhibited prostrate cancer cell invasion and migration. Black-Right-Pointing-Pointer The Neu3-specific siRNA inhibited prostate cancer metastasis in mice. Black-Right-Pointing-Pointer Targeting Neu3 may have utility for gene-based therapy of human cancer metastasis. -- Abstract: Human plasma membrane-associated sialidase (Neu3) is one of several sialidases that hydrolyze sialic acids in the terminal position of the carbohydrate groups of glycolipids and glycoproteins. Neu3 is mainly localized in plasma membranes and plays crucial roles in the regulation of cell surface functions. In this study, we investigated the effects and molecular mechanisms of Neu3 on cell invasion and migration in vivo and in vitro. Initially, we found that the levels of Neu3 expression were higher in prostate cancer tissues and cell lines than in normal prostate tissues based on RT-PCR and Western blotting analyses. We then applied a Neu3 siRNA approach to block Neu3 signaling using PC-3M cells as model cells. Transwell invasion assays and wound assays showed significantly decreased invasion and migration potential in the Neu3 siRNA-transfected cells. RT-PCR and Western blotting analyses revealed that Neu3 knockdown decreased the expressions of the matrix metalloproteinases MMP-2 and MMP-9. In vivo, mice injected with PC-3M cell tumors were evaluated by SPECT/CT to determine the presence of bone metastases. Mice treated with attenuated Salmonella carrying the Neu3 siRNA developed fewer bone metastases than mice treated with attenuated Salmonella carrying a control Scramble siRNA, attenuated Salmonella alone or PBS. The results for bone metastasis detection by pathology were consistent with the data obtained by SPECT/CT. Tumor blocks were evaluated by histochemical, RT-PCR and Western blotting analyses. The results revealed

  14. Treatment-Induced Viral Cure of Hepatitis C Virus-Infected Patients Involves a Dynamic Interplay among three Important Molecular Players in Lipid Homeostasis: Circulating microRNA (miR)-24, miR-223, and Proprotein Convertase Subtilisin/Kexin Type 9.

    Science.gov (United States)

    Hyrina, Anastasia; Olmstead, Andrea D; Steven, Paul; Krajden, Mel; Tam, Edward; Jean, François

    2017-09-01

    In patients with chronic hepatitis C virus (HCV) infection, viral hijacking of the host-cell biosynthetic pathways is associated with altered lipid metabolism, which contributes to disease progression and may influence antiviral response. We investigated the molecular interplay among four key regulators of lipid homeostasis [microRNA (miR)-122, miR-24, miR-223, and proprotein convertase subtilisin/kexin type 9 (PCSK9)] in HCV-infected patients (n=72) who achieved a treatment-based viral cure after interferon-based therapy with first-generation direct-acting antivirals. Real-time PCR was used to quantify microRNA plasma levels, and ELISA assays were used to determine plasma concentrations of PCSK9. We report that levels of miR-24 and miR-223 significantly increased in patients achieving sustained virologic response (SVR), whereas the levels of miR-122, a liver-specific cofactor for HCV infection, decreased in these patients. PCSK9 concentrations were significantly increased in SVRs, suggesting that PCSK9 may help impede viral infection. The modulatory effect of PCSK9 on HCV infection was also demonstrated in the context of HCV-infected Huh-7.5.1 cells employing recombinant human PCSK9 mutants. Together, these results provide insights into a novel coordinated interplay among three important molecular players in lipid homeostasis - circulating miR-24, miR-223 and PCSK9 - whose regulation is affected by HCV infection and treatment-based viral cure. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

  15. Identifying optimal reference genes for the normalization of microRNA expression in cucumber under viral stress

    Science.gov (United States)

    Liang, Chaoqiong; Hao, Jianjun; Meng, Yan; Luo, Laixin; Li, Jianqiang

    2018-01-01

    Cucumber green mottle mosaic virus (CGMMV) is an economically important pathogen and causes significant reduction of both yield and quality of cucumber (Cucumis sativus). Currently, there were no satisfied strategies for controlling the disease. A better understanding of microRNA (miRNA) expression related to the regulation of plant-virus interactions and virus resistance would be of great assistance when developing control strategies for CGMMV. However, accurate expression analysis is highly dependent on robust and reliable reference gene used as an internal control for normalization of miRNA expression. Most commonly used reference genes involved in CGMMV-infected cucumber are not universally expressed depending on tissue types and stages of plant development. It is therefore crucial to identify suitable reference genes in investigating the role of miRNA expression. In this study, seven reference genes, including Actin, Tubulin, EF-1α, 18S rRNA, Ubiquitin, GAPDH and Cyclophilin, were evaluated for the most accurate results in analyses using reverse transcription-quantitative polymerase chain reaction (RT-qPCR). Gene expression was assayed on cucumber leaves, stems and roots that were collected at different days post inoculation with CGMMV. The expression data were analyzed using algorithms including delta-Ct, geNorm, NormFinder, and BestKeeper as well as the comparative tool RefFinder. The reference genes were subsequently validated using miR159. The results showed that EF-1α and GAPDH were the most reliable reference genes for normalizing miRNA expression in leaf, root and stem samples, while Ubiquitin and EF-1α were the most suitable combination overall. PMID:29543906

  16. Plasma long non-coding RNA BACE1 as a novel biomarker for diagnosis of Alzheimer disease.

    Science.gov (United States)

    Feng, Liang; Liao, Yu-Ting; He, Jin-Cai; Xie, Cheng-Long; Chen, Si-Yan; Fan, Hui-Hui; Su, Zhi-Peng; Wang, Zhen

    2018-01-09

    Long non-coding RNA (LncRNA) have been reported to be involved in the pathogenesis of neurodegenerative diseases, but whether it can serve as a biomarker for Alzheimer disease (AD) is not yet known. The present study selected four specific LncRNA (17A, 51A, BACE1 and BC200) as possible AD biomarker. RT-qPCR was performed to validate the LncRNA. Receiver operating characteristic curve (ROC) and area under the ROC curve (AUC) were applied to study the potential of LncRNA as a biomarker in a population of 88 AD patients and 72 control individuals. We found that the plasma LncRNA BACE1 level of AD patients was significantly higher than that of healthy controls (p = 0.006). Plasma level of LncRNA 17A, 51A and BC200 did not show a significant difference between two groups (p = 0.098, p = 0.204 and p = 0.232, respectively). ROC curve analysis showed that LncRNA BACE1 was the best candidate of these LncRNA (95% CI: 0.553-0.781, p = 0.003). In addition, no correlation was found for expression of these LncRNA in both control and AD groups with age or MMSE scale (p > 0.05). Our present study compared the plasma level of four LncRNA between AD and non-AD patients, and found that the level of the BACE1 is increased in the plasma of AD patients and have a high specificity (88%) for AD, indicating BACE1 may be a potential candidate biomarker to predict AD.

  17. Mass spectrometric detection of siRNA in plasma samples for doping control purposes.

    Science.gov (United States)

    Kohler, Maxie; Thomas, Andreas; Walpurgis, Katja; Schänzer, Wilhelm; Thevis, Mario

    2010-10-01

    Small interfering ribonucleic acid (siRNA) molecules can effect the expression of any gene by inducing the degradation of mRNA. Therefore, these molecules can be of interest for illicit performance enhancement in sports by affecting different metabolic pathways. An example of an efficient performance-enhancing gene knockdown is the myostatin gene that regulates muscle growth. This study was carried out to provide a tool for the mass spectrometric detection of modified and unmodified siRNA from plasma samples. The oligonucleotides are purified by centrifugal filtration and the use of an miRNA purification kit, followed by flow-injection analysis using an Exactive mass spectrometer to yield the accurate masses of the sense and antisense strands. Although chromatography and sensitive mass spectrometric analysis of oligonucleotides are still challenging, a method was developed and validated that has adequate sensitivity (limit of detection 0.25-1 nmol mL(-1)) and performance (precision 11-21%, recovery 23-67%) for typical antisense oligonucleotides currently used in clinical studies.

  18. ACVP-05: Virus Genetic Analysis from Cell-Free Plasma, Virally Infected Cells or Tissues and Cultured Supernatant Via Single Genome Amplification and Direct Sequencing | Frederick National Laboratory for Cancer Research

    Science.gov (United States)

    The Viral Evolution Core within the AIDS and Cancer Virus Program will extract viral RNA/DNA from cell-free or cell-associated samples. Complementary (cDNA) will be generated as needed, and cDNA or DNA will be diluted to a single copy prior to nested

  19. Viral precursor protein P3 and its processed products perform discrete and essential functions in the poliovirus RNA replication complex

    Science.gov (United States)

    The differential use of protein precursors and their products is a key strategy used during poliovirus replication. To characterize the role of protein precursors during replication, we examined the complementation profiles of mutants that inhibited 3D polymerase or 3C-RNA binding activity. We showe...

  20. 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

  1. Identification of constrained peptides that bind to and preferentially inhibit the activity of the hepatitis C viral RNA-dependent RNA polymerase

    International Nuclear Information System (INIS)

    Amin, Anthony; Zaccardi, Joe; Mullen, Stanley; Olland, Stephane; Orlowski, Mark; Feld, Boris; Labonte, Patrick; Mak, Paul

    2003-01-01

    A class of disulfide constrained peptides containing a core motif FPWG was identified from a screen of phage displayed library using the HCV RNA-dependent RNA polymerase (NS5B) as a bait. Surface plasmon resonance studies showed that three highly purified synthetic constrained peptides bound to immobilized NS5B with estimated K d values ranging from 30 to 60 μM. In addition, these peptides inhibited the NS5B activity in vitro with IC 50 ranging from 6 to 48 μM, whereas in contrast they had no inhibitory effect on the enzymatic activities of calf thymus polymerase α, human polymerase β, RSV polymerase, and HIV reverse transcriptase in vitro. Two peptides demonstrated conformation-dependent inhibition since their synthetic linear versions were not inhibitory in the NS5B assay. A constrained peptide with the minimum core motif FPWG retained selective inhibition of NS5B activity with an IC 50 of 50 μM. Alanine scan analyses of a representative constrained peptide, FPWGNTW, indicated that residues F1 and W7 were critical for the inhibitory effect of this peptide, although residues P2 and N5 had some measurable inhibitory effect as well. Further analyses of the mechanism of inhibition indicated that these peptides inhibited the formation of preelongation complexes required for the elongation reaction. However, once the preelongation complex was formed, its activity was refractory to peptide inhibition. Furthermore, the constrained peptide FPWGNTW inhibited de novo initiated RNA synthesis by NS5B from a poly(rC) template. These data indicate that the peptides confer selective inhibition of NS5B activity by binding to the enzyme and perturbing an early step preceding the processive elongation step of RNA synthesis

  2. Individual co-variation between viral RNA load and gene expression reveals novel host factors during early dengue virus infection of the Aedes aegypti midgut.

    Directory of Open Access Journals (Sweden)

    Vincent Raquin

    2017-12-01

    Full Text Available Dengue virus (DENV causes more human infections than any other mosquito-borne virus. The current lack of antiviral strategies has prompted genome-wide screens for host genes that are required for DENV infectivity. Earlier transcriptomic studies that identified DENV host factors in the primary vector Aedes aegypti used inbred laboratory colonies and/or pools of mosquitoes that erase individual variation. Here, we performed transcriptome sequencing on individual midguts in a field-derived Ae. aegypti population to identify new candidate host factors modulating DENV replication. We analyzed the transcriptomic data using an approach that accounts for individual co-variation between viral RNA load and gene expression. This approach generates a prediction about the agonist or antagonist effect of candidate genes on DENV replication based on the sign of the correlation between gene expression and viral RNA load. Using this method, we identified 39 candidate genes that went undetected by conventional pairwise comparison of gene expression levels between DENV-infected midguts and uninfected controls. Only four candidate genes were detected by both methods, emphasizing their complementarity. We demonstrated the value of our approach by functional validation of a candidate agonist gene encoding a sterol regulatory element-binding protein (SREBP, which was identified by correlation analysis but not by pairwise comparison. We confirmed that SREBP promotes DENV infection in the midgut by RNAi-mediated gene knockdown in vivo. We suggest that our approach for transcriptomic analysis can empower genome-wide screens for potential agonist or antagonist factors by leveraging inter-individual variation in gene expression. More generally, this method is applicable to a wide range of phenotypic traits displaying inter-individual variation.

  3. Detection of high levels of European bat lyssavirus type-1 viral RNA in the thyroid gland of experimentally-infected Eptesicus fuscus bats.

    Science.gov (United States)

    Fooks, A R; Johnson, N; Müller, T; Vos, A; Mansfield, K; Hicks, D; Nunez, A; Freuling, C; Neubert, L; Kaipf, I; Denzinger, A; Franka, R; Rupprecht, C E

    2009-08-01

    Two common bat lyssavirus species have been identified in many European countries: European bat lyssavirus type-1 and -2 (EBLV-1 and EBLV-2). Only limited knowledge on the susceptibility of the natural EBLV-hosts, insectivorous bats, to lyssavirus infection is available. Our study was undertaken to evaluate the susceptibility and pathology associated with an EBLV-1 infection in Eptesicus fuscus following different routes of virus inoculation including intracranial (n = 6), intramuscular (n = 14), oral (n = 7) and intranasal (n = 7). Blood and saliva samples were collected from all bats on a monthly basis. Four bats inoculated intracranially developed rabies with a mean of 11 days to death, whilst seven bats inoculated intramuscularly developed rabies, with an extended incubation period prior to death. We did not observe any mortality in the oral (p.o.) or intranasal (i.n.) groups and both groups had detectable levels of virus neutralizing antibodies (data not shown). Virus shedding was demonstrated in the saliva by virus isolation and the detection of viral RNA in ill bats, particularly immediately prior to the development of disease. In addition, the presence of virus and viral RNA was detected in the thyroid gland in bats challenged experimentally with EBLV-1, which exceeded that detected in all other extra-neural tissue. The significance of detecting EBLV-1 in the thyroid gland of rabid bats is not well understood. We speculate that the infection of the thyroid gland may cause subacute thyroiditis, a transient form of thyroiditis causing hyperthyroidism, resulting in changes in adrenocortical activity that could lead to hormonal dysfunction, thereby distinguishing the clinical presentation of rabies in the rabid host.

  4. Evaluation of Nucleic Acid Stabilization Products for Ambient Temperature Shipping and Storage of Viral RNA and Antibody in a Dried Whole Blood Format

    Science.gov (United States)

    Dauner, Allison L.; Gilliland, Theron C.; Mitra, Indrani; Pal, Subhamoy; Morrison, Amy C.; Hontz, Robert D.; Wu, Shuenn-Jue L.

    2015-01-01

    Loss of sample integrity during specimen transport can lead to false-negative diagnostic results. In an effort to improve upon the status quo, we used dengue as a model RNA virus to evaluate the stabilization of RNA and antibodies in three commercially available sample stabilization products: Whatman FTA Micro Cards (GE Healthcare Life Sciences, Pittsburgh, PA), DNAstāble Blood tubes (Biomātrica, San Diego, CA), and ViveST tubes (ViveBio, Alpharetta, GA). Both contrived and clinical dengue-positive specimens were stored on these products at ambient temperature or 37°C for up to 1 month. Antibody and viral RNA levels were measured by enzyme-linked immunosorbent assay (ELISA) and quantitative reverse transcription polymerase chain reaction (qRT-PCR) assays, respectively, and compared with frozen unloaded controls. We observed reduced RNA and antibody levels between stabilized contrived samples and frozen controls at our earliest time point, and this was particularly pronounced for the FTA cards. However, despite some time and temperature dependent loss, a 94.6–97.3% agreement was observed between stabilized clinical specimens and their frozen controls for all products. Additional considerations such as cost, sample volume, matrix, and ease of use should inform any decision to incorporate sample stabilization products into a diagnostic testing workflow. We conclude that DNAstāble Blood and ViveST tubes are useful alternatives to traditional filter paper for ambient temperature shipment of clinical specimens for downstream molecular and serological testing. PMID:25940193

  5. Remodeling of the Host Cell Plasma Membrane by HIV-1 Nef and Vpu: A Strategy to Ensure Viral Fitness and Persistence.

    Science.gov (United States)

    Sugden, Scott M; Bego, Mariana G; Pham, Tram N Q; Cohen, Éric A

    2016-03-03

    The plasma membrane protects the cell from its surroundings and regulates cellular communication, homing, and metabolism. Not surprisingly, the composition of this membrane is highly controlled through the vesicular trafficking of proteins to and from the cell surface. As intracellular pathogens, most viruses exploit the host plasma membrane to promote viral replication while avoiding immune detection. This is particularly true for the enveloped human immunodeficiency virus (HIV), which assembles and obtains its lipid shell directly at the plasma membrane. HIV-1 encodes two proteins, negative factor (Nef) and viral protein U (Vpu), which function primarily by altering the quantity and localization of cell surface molecules to increase virus fitness despite host antiviral immune responses. These proteins are expressed at different stages in the HIV-1 life cycle and employ a variety of mechanisms to target both unique and redundant surface proteins, including the viral receptor CD4, host restriction factors, immunoreceptors, homing molecules, tetraspanins and membrane transporters. In this review, we discuss recent progress in the study of the Nef and Vpu targeting of host membrane proteins with an emphasis on how remodeling of the cell membrane allows HIV-1 to avoid host antiviral immune responses leading to the establishment of systemic and persistent infection.

  6. NS3 from Hepatitis C Virus Strain JFH-1 Is an Unusually Robust Helicase That Is Primed To Bind and Unwind Viral RNA

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Ting; Ren, Xiaoming; Adams, Rebecca L.; Pyle, Anna Marie; Ou, J. -H. James

    2017-10-25

    Hepatitis C viruses (HCV) encode a helicase enzyme that is essential for viral replication and assembly (nonstructural protein 3 [NS3]). This helicase has become the focus of extensive basic research on the general helicase mechanism, and it is also of interest as a novel drug target. Despite the importance of this protein, mechanistic work on NS3 has been conducted almost exclusively on variants from HCV genotype 1. Our understanding of NS3 from the highly active HCV strains that are used to study HCV genetics and mechanism in cell culture (such as JFH-1) is lacking. We therefore set out to determine whether NS3 from the replicatively efficient genotype 2a strain JFH-1 displays novel functional or structural properties. Using biochemical assays for RNA binding and duplex unwinding, we show that JFH-1 NS3 binds RNA much more rapidly than the previously studied NS3 variants from genotype 1b. Unlike NS3 variants from other genotypes, JFH-1 NS3 binds RNA with high affinity in a functionally active form that is capable of immediately unwinding RNA duplexes without undergoing rate-limiting conformational changes that precede activation. Unlike other superfamily 2 (SF2) helicases, JFH-1 NS3 does not require long 3' overhangs, and it unwinds duplexes that are flanked by only a few nucleotides, as in the folded HCV genome. To understand the physical basis for this, we solved the crystal structure of JFH-1 NS3, revealing a novel conformation that contains an open, positively charged RNA binding cleft that is primed for productive interaction with RNA targets, potentially explaining robust replication by HCV JFH-1.

    IMPORTANCEGenotypes of HCV are as divergent as different types of flavivirus, and yet mechanistic features of HCV variants are presumed to be held in common. One of the most well-studied components of the HCV replication complex is a helicase known as nonstructural protein 3 (NS3). We set out to determine whether this important

  7. Identification of messenger RNA of fetoplacental source in maternal plasma of women with normal pregnancies and pregnancies with intrauterine growth restriction.

    Science.gov (United States)

    Ayala Ramírez, Paola; García Robles, Reggie; Rojas, Juan Diego; Bermúdez, Martha; Bernal, Jaime

    2012-07-01

    to quantify placenta-specific RNA in plasma of women carrying foetuses with intrauterine growth restriction and pregnant women with normal pregnancies. 8 pregnant women with foetuses with intrauterine growth restriction were studied as well as 18 women with uncomplicated pregnancies in the third pregnancy trimester. Total free RNA was quantified in maternal plasma by spectrophotometry and the gene expression of hPL (Human Placental Lactogen) at the messenger RNA level through technical Real Time-Chain Reaction Polymerase. plasma RNA of fetoplacental origin was successfully detected in 100% of pregnant women. There were no statistically significant differences between the values of total RNA extracted from plasma (p= 0.5975) nor in the messenger RNA expression of hPL gene (p= 0.5785) between cases and controls. messenger RNA of fetoplacental origin can be detected in maternal plasma during pregnancy.

  8. A Luciferase Reporter Gene Assay to Measure Ebola Virus Viral Protein 35-Associated Inhibition of Double-Stranded RNA-Stimulated, Retinoic Acid-Inducible Gene 1-Mediated Induction of Interferon β.

    Science.gov (United States)

    Cannas, Valeria; Daino, Gian Luca; Corona, Angela; Esposito, Francesca; Tramontano, Enzo

    2015-10-01

    During Ebola virus (EBOV) infection, the type I interferon α/β (IFN-α/β) innate immune response is suppressed by EBOV viral protein 35 (VP35), a validated drug target. Identification of EBOV VP35 inhibitors requires a cellular system able to assess the VP35-based inhibitory functions of viral double-stranded RNA (dsRNA) IFN-β induction. We established a miniaturized luciferase gene reporter assay in A549 cells that measures IFN-β induction by viral dsRNA and is dose-dependently inhibited by VP35 expression. When compared to influenza A virus NS1 protein, EBOV VP35 showed improved inhibition of viral dsRNA-based IFN-β induction. This assay can be used to screen for EBOV VP35 inhibitors. © The Author 2015. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  9. Full-length single-cell RNA-seq applied to a viral human cancer: applications to HPV expression and splicing analysis in HeLa S3 cells.

    Science.gov (United States)

    Wu, Liang; Zhang, Xiaolong; Zhao, Zhikun; Wang, Ling; Li, Bo; Li, Guibo; Dean, Michael; Yu, Qichao; Wang, Yanhui; Lin, Xinxin; Rao, Weijian; Mei, Zhanlong; Li, Yang; Jiang, Runze; Yang, Huan; Li, Fuqiang; Xie, Guoyun; Xu, Liqin; Wu, Kui; Zhang, Jie; Chen, Jianghao; Wang, Ting; Kristiansen, Karsten; Zhang, Xiuqing; Li, Yingrui; Yang, Huanming; Wang, Jian; Hou, Yong; Xu, Xun

    2015-01-01

    Viral infection causes multiple forms of human cancer, and HPV infection is the primary factor in cervical carcinomas. Recent single-cell RNA-seq studies highlight the tumor heterogeneity present in most cancers, but virally induced tumors have not been studied. HeLa is a well characterized HPV+ cervical cancer cell line. We developed a new high throughput platform to prepare single-cell RNA on a nanoliter scale based on a customized microwell chip. Using this method, we successfully amplified full-length transcripts of 669 single HeLa S3 cells and 40 of them were randomly selected to perform single-cell RNA sequencing. Based on these data, we obtained a comprehensive understanding of the heterogeneity of HeLa S3 cells in gene expression, alternative splicing and fusions. Furthermore, we identified a high diversity of HPV-18 expression and splicing at the single-cell level. By co-expression analysis we identified 283 E6, E7 co-regulated genes, including CDC25, PCNA, PLK4, BUB1B and IRF1 known to interact with HPV viral proteins. Our results reveal the heterogeneity of a virus-infected cell line. It not only provides a transcriptome characterization of HeLa S3 cells at the single cell level, but is a demonstration of the power of single cell RNA-seq analysis of virally infected cells and cancers.

  10. Specific micro RNA-regulated TetR-KRAB transcriptional control of transgene expression in viral vector-transduced cells.

    Directory of Open Access Journals (Sweden)

    Virginie Pichard

    Full Text Available Precise control of transgene expression in a tissue-specific and temporally regulated manner is desirable for many basic and applied investigations gene therapy applications. This is important to regulate dose of transgene products and minimize unwanted effects. Previously described methods have employed tissue specific promoters, miRNA-based transgene silencing or tetR-KRAB-mediated suppression of transgene promoters. To improve on versatility of transgene expression control, we have developed expression systems that use combinations of a tetR-KRAB artificial transgene-repressor, endogenous miRNA silencing machinery and tissue specific promoters. Precise control of transgene expression was demonstrated in liver-, macrophage- and muscle-derived cells. Efficiency was also demonstrated in vivo in murine muscle. This multicomponent and modular regulatory system provides a robust and easily adaptable method for achieving regulated transgene expression in different tissue types. The improved precision of regulation will be useful for many gene therapy applications requiring specific spatiotemporal transgene regulation.

  11. Inhibition of iridovirus protein synthesis and virus replication by antisense morpholino oligonucleotides targeted to the major capsid protein, the 18 kDa immediate-early protein, and a viral homolog of RNA polymerase II

    International Nuclear Information System (INIS)

    Sample, Robert; Bryan, Locke; Long, Scott; Majji, Sai; Hoskins, Glenn; Sinning, Allan; Olivier, Jake; Chinchar, V. Gregory

    2007-01-01

    Frog virus 3 (FV3) is a large DNA virus that encodes ∼ 100 proteins. Although the general features of FV3 replication are known, the specific roles that most viral proteins play in the virus life cycle have not yet been elucidated. To address the question of viral gene function, antisense morpholino oligonucleotides (asMOs) were used to transiently knock-down expression of specific viral genes and thus infer their role in virus replication. We designed asMOs directed against the major capsid protein (MCP), an 18 kDa immediate-early protein (18K) that was thought to be a viral regulatory protein, and the viral homologue of the largest subunit of RNA polymerase II (vPol-IIα). All three asMOs successfully inhibited translation of the targeted protein, and two of the three asMOs resulted in marked phenotypic changes. Knock-down of the MCP resulted in a marked reduction in viral titer without a corresponding drop in the synthesis of other late viral proteins. Transmission electron microscopy (TEM) showed that in cells treated with the anti-MCP MO assembly sites were devoid of viral particles and contained numerous aberrant structures. In contrast, inhibition of 18K synthesis did not block virion formation, suggesting that the 18K protein was not essential for replication of FV3 in fathead minnow (FHM) cells. Finally, consistent with the view that late viral gene expression is catalyzed by a virus-encoded or virus-modified Pol-II-like protein, knock-down of vPol-IIα triggered a global decline in late gene expression and virus yields without affecting the synthesis of early viral genes. Collectively, these results demonstrate the utility of using asMOs to elucidate the function of FV3 proteins

  12. viRome: an R package for the visualization and analysis of viral small RNA sequence datasets.

    Science.gov (United States)

    Watson, Mick; Schnettler, Esther; Kohl, Alain

    2013-08-01

    RNA interference (RNAi) is known to play an important part in defence against viruses in a range of species. Second-generation sequencing technologies allow us to assay these systems and the small RNAs that play a key role with unprecedented depth. However, scientists need access to tools that can condense, analyse and display the resulting data. Here, we present viRome, a package for R that takes aligned sequence data and produces a range of essential plots and reports. viRome is released under the BSD license as a package for R available for both Windows and Linux http://virome.sf.net. Additional information and a tutorial is available on the ARK-Genomics website: http://www.ark-genomics.org/bioinformatics/virome. mick.watson@roslin.ed.ac.uk.

  13. Circulating Plasma Levels of MicroRNA-21 and MicroRNA-221 Are Potential Diagnostic Markers for Primary Intrahepatic Cholangiocarcinoma

    Science.gov (United States)

    Kemeny, Nancy; Kingham, T. Peter; Allen, Peter J.; D’Angelica, Michael I.; DeMatteo, Ronald P.; Betel, Doron; Klimstra, David; Jarnagin, William R.; Ventura, Andrea

    2016-01-01

    Background MicroRNAs (miRNAs) are potential biomarkers in various malignancies. We aim to characterize miRNA expression in intrahepatic cholangiocarcinoma (ICC) and identify circulating plasma miRNAs with potential diagnostic and prognostic utility. Methods Using deep-sequencing techniques, miRNA expression between tumor samples and non-neoplastic liver parenchyma were compared. Overexpressed miRNAs were measured in plasma from an independent cohort of patients with cholangiocarcinoma using RT-qPCR and compared with that healthy volunteers. The discriminatory ability of the evaluated plasma miRNAs between patients and controls was evaluated with receiving operating characteristic (ROC) curves. Results Small RNAs from 12 ICC and 11 tumor-free liver samples were evaluated. Unsupervised hierarchical clustering using the miRNA expression data showed clear grouping of ICC vs. non-neoplastic liver parenchyma. We identified 134 down-regulated and 128 upregulated miRNAs. Based on overexpression and high fold-change, miR21, miR200b, miR221, and miR34c were measured in plasma from an independent cohort of patients with ICC (n = 25) and healthy controls (n = 7). Significant overexpression of miR-21 and miR-221 was found in plasma from ICC patients. Furthermore, circulating miR-21 demonstrated a high discriminatory ability between patients with ICC and healthy controls (AUC: 0.94). Conclusion Among the differentially expressed miRNAs in ICC, miR-21 and miR-221 are overexpressed and detectable in the circulation. Plasma expression levels of these miRNAs, particularly miR-21, accurately differentiates patients with ICC from healthy controls and could potentially serve as adjuncts in diagnosis. Prospective validation and comparison with other hepatobiliary malignancies is required to establish their potential role as diagnostic and prognostic biomarkers. PMID:27685844

  14. Cell-free placental mRNA in maternal plasma to predict placental invasion in patients with placenta accreta.

    Science.gov (United States)

    El Behery, Manal M; Rasha L, Etewa; El Alfy, Yehya

    2010-04-01

    To evaluate whether measuring cell-free placental mRNA in maternal plasma improves the diagnostic accuracy of ultrasound and color Doppler in detecting placental invasion in patients at risk for placenta accreta. Thirty-five singleton pregnant women of more than 28 weeks of gestation and at risk for placenta accreta underwent ultrasound and color Doppler assessment. Cell-free placental mRNA in maternal plasma was measured using real-time reverse-transcription polymerase chain reaction. Patients were classified into 2 groups based on the findings at cesarean delivery and histological examination: women with placenta accreta (n=7) and women without placenta accreta (n=28). The median MoM (multiples of the median) value of cell-free placental mRNA was significantly higher in patients with placenta accreta than in those without placenta accreta (6.50 vs 2.60; Pplacental mRNA was significantly elevated in patients with placenta increta and percreta than in those with simple accreta. Six false-positive results were found on ultrasound, all from patients without placenta accreta and an insignificant rise in cell-free placental mRNA levels. Measuring cell-free placental mRNA in maternal plasma may increase the accuracy of ultrasound and color Doppler in prenatal prediction of placental invasion in patients with suspected placenta accreta. Copyright 2009 International Federation of Gynecology and Obstetrics. Published by Elsevier Ireland Ltd. All rights reserved.

  15. A plasma microRNA signature as a biomarker for acquired aplastic anemia.

    Science.gov (United States)

    Hosokawa, Kohei; Kajigaya, Sachiko; Feng, Xingmin; Desierto, Marie J; Fernandez Ibanez, Maria Del Pilar; Rios, Olga; Weinstein, Barbara; Scheinberg, Phillip; Townsley, Danielle M; Young, Neal S

    2017-01-01

    Aplastic anemia is an acquired bone marrow failure characterized by marrow hypoplasia, a paucity of hematopoietic stem and progenitor cells, and pancytopenia of the peripheral blood, due to immune attack on the bone marrow. In aplastic anemia, a major challenge is to develop immune biomarkers to monitor the disease. We measured circulating microRNAs in plasma samples of aplastic anemia patients in order to identify disease-specific microRNAs. A total of 179 microRNAs were analyzed in 35 plasma samples from 13 aplastic anemia patients, 11 myelodysplastic syndrome patients, and 11 healthy controls using the Serum/Plasma Focus microRNA Polymerase Chain Reaction Panel. Subsequently, 19 microRNAs from the discovery set were investigated in the 108 plasma samples from 41 aplastic anemia patients, 24 myelodysplastic syndrome patients, and 43 healthy controls for validation, confirming that 3 microRNAs could be validated as dysregulated (>1.5-fold change) in aplastic anemia, compared to healthy controls. MiR-150-5p (induction of T-cell differentiation) and miR-146b-5p (involvement in the feedback regulation of innate immune response) were elevated in aplastic anemia plasma, whereas miR-1 was decreased in aplastic anemia. By receiver operating characteristic curve analysis, we developed a logistic model with these 3 microRNAs that enabled us to predict the probability of a diagnosis of aplastic anemia with an area under the curve of 0.86. Dysregulated expression levels of the microRNAs became normal after immunosuppressive therapy at 6 months. Specifically, miR-150-5p expression was significantly reduced after successful immunosuppressive therapy, but did not change in non-responders. We propose 3 novel plasma biomarkers in aplastic anemia, in which miR-150-5p, miR-146b-5p, and miR-1 can serve for diagnosis and miR-150-5p for disease monitoring. Clinicaltrials.gov identifiers:00260689, 00217594, 00961064. Copyright© Ferrata Storti Foundation.

  16. A predominance of R5-like HIV genotypes in vaginal secretions is associated with elevated plasma HIV-1 RNA levels and the absence of anti-retroviral therapy

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    Lacour Nedra

    2008-07-01

    Full Text Available Abstract HIV expressed in genital secretions provides the inoculum from which transmitting variants are selected, both in sexual transmission and mother-to-infant transmission during partuition. Characterization of HIV levels and genotypes found in vaginal secretions and the impact of anti-retroviral therapy (ART on this virus can provide valuable insight for the prevention of HIV transmission. Vaginal HIV was evaluated in a cohort of 43 women attending a New Orleans HIV outpatient clinic. Predominant vaginal genotypes were characterized as R5- or X4-like by heteroduplex tracking analyses of the envelope V3 region. Most women (67.4% shed R5-like genotypes in vaginal secretions which was associated with elevated plasma HIV levels (≥ 10,000 copies HIV-RNA/mL and absence of ART. Because R5-like genotypes are more frequently associated with transmission, these observations suggest that the majority of women shedding HIV in genital secretions present a transmission risk. The levels of vaginal virus were similar between both groups, but shedding of X4-like genotypes was associated with lower plasma viral loads and the use of ART, suggesting that ART use may impact the genotypes of virus found in the female genital compartment.

  17. Viral Hepatitis

    Science.gov (United States)

    ... Home A-Z Health Topics Viral hepatitis Viral hepatitis > A-Z Health Topics Viral hepatitis (PDF, 90 ... liver. Source: National Cancer Institute Learn more about hepatitis Watch a video. Learn who is at risk ...

  18. A search for RNA insertions and NS3 gene duplication in the genome of cytopathic isolates of bovine viral diarrhea virus

    Directory of Open Access Journals (Sweden)

    V.L. Quadros

    2006-07-01

    Full Text Available Calves born persistently infected with non-cytopathic bovine viral diarrhea virus (ncpBVDV frequently develop a fatal gastroenteric illness called mucosal disease. Both the original virus (ncpBVDV and an antigenically identical but cytopathic virus (cpBVDV can be isolated from animals affected by mucosal disease. Cytopathic BVDVs originate from their ncp counterparts by diverse genetic mechanisms, all leading to the expression of the non-structural polypeptide NS3 as a discrete protein. In contrast, ncpBVDVs express only the large precursor polypeptide, NS2-3, which contains the NS3 sequence within its carboxy-terminal half. We report here the investigation of the mechanism leading to NS3 expression in 41 cpBVDV isolates. An RT-PCR strategy was employed to detect RNA insertions within the NS2-3 gene and/or duplication of the NS3 gene, two common mechanisms of NS3 expression. RT-PCR amplification revealed insertions in the NS2-3 gene of three cp isolates, with the inserts being similar in size to that present in the cpBVDV NADL strain. Sequencing of one such insert revealed a 296-nucleotide sequence with a central core of 270 nucleotides coding for an amino acid sequence highly homologous (98% to the NADL insert, a sequence corresponding to part of the cellular J-Domain gene. One cpBVDV isolate contained a duplication of the NS3 gene downstream from the original locus. In contrast, no detectable NS2-3 insertions or NS3 gene duplications were observed in the genome of 37 cp isolates. These results demonstrate that processing of NS2-3 without bulk mRNA insertions or NS3 gene duplications seems to be a frequent mechanism leading to NS3 expression and BVDV cytopathology.

  19. The Regulatory and Kinase Domains but Not the Interdomain Linker Determine Human Double-stranded RNA-activated Kinase (PKR) Sensitivity to Inhibition by Viral Non-coding RNAs.

    Science.gov (United States)

    Sunita, S; Schwartz, Samantha L; Conn, Graeme L

    2015-11-20

    Double-stranded RNA (dsRNA)-activated protein kinase (PKR) is an important component of the innate immune system that presents a crucial first line of defense against viral infection. PKR has a modular architecture comprising a regulatory N-terminal dsRNA binding domain and a C-terminal kinase domain interposed by an unstructured ∼80-residue interdomain linker (IDL). Guided by sequence alignment, we created IDL deletions in human PKR (hPKR) and regulatory/kinase domain swap human-rat chimeric PKRs to assess the contributions of each domain and the IDL to regulation of the kinase activity by RNA. Using circular dichroism spectroscopy, limited proteolysis, kinase assays, and isothermal titration calorimetry, we show that each PKR protein is properly folded with similar domain boundaries and that each exhibits comparable polyinosinic-cytidylic (poly(rI:rC)) dsRNA activation profiles and binding affinities for adenoviral virus-associated RNA I (VA RNAI) and HIV-1 trans-activation response (TAR) RNA. From these results we conclude that the IDL of PKR is not required for RNA binding or mediating changes in protein conformation or domain interactions necessary for PKR regulation by RNA. In contrast, inhibition of rat PKR by VA RNAI and TAR RNA was found to be weaker than for hPKR by 7- and >300-fold, respectively, and each human-rat chimeric domain-swapped protein showed intermediate levels of inhibition. These findings indicate that PKR sequence or structural elements in the kinase domain, present in hPKR but absent in rat PKR, are exploited by viral non-coding RNAs to accomplish efficient inhibition of PKR. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

  20. The relative prognostic value of plasma HIV RNA levels and CD4 lymphocyte counts in advanced HIV infection

    DEFF Research Database (Denmark)

    Cozzi-Lepri, A; Katzenstein, T L; Ullum, H

    1998-01-01

    . RESULTS: The plasma HIV RNA (median 101410 copies/ml; range (range 200-7200000) and the CD4 lymphocyte count (median 250 cells x 10(6)/l; range 1-1247) were negatively correlated (Pearson r = -0.53; P

  1. Plasma MicroRNA Profiles in Patients with Early Rheumatoid Arthritis Responding to Adalimumab plus Methotrexate vs Methotrexate Alone

    DEFF Research Database (Denmark)

    Sode, Jacob; Krintel, Sophine B; Carlsen, Anting Liu

    2018-01-01

    OBJECTIVE: The aim was to identify plasma (i.e., cell-free) microRNA (miRNA) predicting antitumor necrosis and/or methotrexate (MTX) treatment response in patients enrolled in an investigator-initiated, prospective, double-blinded, placebo-controlled trial (The OPERA study, NCT00660647). METHODS......: We included 180 disease-modifying antirheumatic drug-naive patients with early rheumatoid arthritis (RA) randomized to adalimumab (ADA; n = 89) or placebo (n = 91) in combination with MTX. Plasma samples before and 3 months after treatment initiation were analyzed for 91 specific mi...... multivariate miRNA models were able to predict response to ADA treatment after 3 and 12 months, with 63% and 82% area under the ROC curves, respectively. CONCLUSION: We identified miR-27a-3p as a potential predictive biomarker of ACR/EULAR remission in patients with early RA treated with ADA in combination...

  2. Design, synthesis, and evaluation of bioactive molecules; Quantification of tricyclic pyrones from pharmacokinetic studies; Nanodelivery of siRNA; and Synthesis of viral protease inhibitors

    Science.gov (United States)

    Weerasekara, Sahani Manjitha

    Four research projects were carried out and they are described in this dissertation. Glycogen synthase kinase-3 beta (GSK3?) plays a pivotal and central role in the pathogenesis of Alzheimer's disease (AD) and protein kinase C (PKC) controls the function of other proteins via phosphorylation and involves in tumor promotion. In pursuit of identifying novel GSK3beta and/or PKC inhibitors, substituted quinoline molecules were designed and synthesized based on the structure-activity-relationship studies. Synthesized molecules were evaluated for their neural protective activities and selected molecules were further tested for inhibitory activities on GSK3beta and PKC enzymes. Among these compounds, compound 2 was found to have better GSK3beta enzyme inhibitory and MC65 cell protection activities at low nanomolar concentrations and poor PKC inhibitory activity whereas compound 3 shows better PKC inhibitory activity. This demonstrates the potential for uses of quinoline scaffold in designing novel compounds for AD and cancer. Pharmacokinetics and distribution profiles of two anti-Alzheimer molecules, CP2 and TP70, discovered in our laboratory were assessed using HPLC/MS. Plasma samples of mice and rats fed with TP70 via different routes over various times were analyzed to quantify the amounts of TP70 in plasma of both species. Distribution profiles of TP70 in various tissues of mice were studied and results show that TP70 penetrated the blood brain barrier and accumulated in the brain tissue in significant amounts. Similarly, the amount of CP2 in plasma of mice was analyzed. The HPLC analysis revealed that both compounds have good PK profiles and bioavailability, which would make them suitable candidates for further in vivo efficacy studies. Nanodelivery of specific dsRNA for suppressing the western corn rootworm (WCR, Diabrotica virgifera virgifera) genes was studied using modified chitosan or modified polyvinylpyrrolidinone (PVP) as nanocarriers. Computational

  3. Altered expression of circulating microRNA in plasma of patients with primary osteoarthritis and in silico analysis of their pathways.

    Directory of Open Access Journals (Sweden)

    Verónica M Borgonio Cuadra

    Full Text Available OBJECTIVE: To analyze a set of circulating microRNA (miRNA in plasma from patients with primary Osteoarthritis (OA and describe the biological significance of altered miRNA in OA based on an in silico analysis of their target genes. METHODS: miRNA expression was analyzed using TaqMan Low Density Arrays and independent assays. The search for potential messenger RNA (mRNA targets of the differentially expressed miRNA was performed by means of the miRWalk and miRecords database; we conducted the biological relevance of the predicted miRNA targets by pathway analysis with the Reactome and DAVID databases. RESULTS: We measured the expression of 380 miRNA in OA; 12 miRNA were overexpressed under the OA condition (p value, ≤0.05; fold change, >2. These results were validated by the detection of some selected miRNA by quantitative PCR (qPCR. In silico analysis showed that target messenger RNA (mRNA were potentially regulated by these miRNA, including genes such as SMAD1, IL-1B, COL3A, VEGFA, and FGFR1, important in chondrocyte maintenance and differentiation. Some metabolic pathways affected by the miRNA: mRNA ratio are signaling Bone morphogenetic proteins (BMP, Platelet-derived growth factor (PDGF, and Nerve growth factor (NGF, these latter two involved in the process of pain. CONCLUSIONS: We identified 12 miRNA in the plasma of patients with primary OA. Specific miRNA that are altered in the disease could be released into plasma, either due to cartilage damage or to an inherent cellular mechanism. Several miRNA could regulate genes and pathways related with development of the disease; eight of these circulating miRNA are described, to our knowledge, for first time in OA.

  4. Haploid genetic screens identify an essential role for PLP2 in the downregulation of novel plasma membrane targets by viral E3 ubiquitin ligases.

    Directory of Open Access Journals (Sweden)

    Richard T Timms

    Full Text Available The Kaposi's sarcoma-associated herpesvirus gene products K3 and K5 are viral ubiquitin E3 ligases which downregulate MHC-I and additional cell surface immunoreceptors. To identify novel cellular genes required for K5 function we performed a forward genetic screen in near-haploid human KBM7 cells. The screen identified proteolipid protein 2 (PLP2, a MARVEL domain protein of unknown function, as essential for K5 activity. Genetic loss of PLP2 traps the viral ligase in the endoplasmic reticulum, where it is unable to ubiquitinate and degrade its substrates. Subsequent analysis of the plasma membrane proteome of K5-expressing KBM7 cells in the presence and absence of PLP2 revealed a wide range of novel K5 targets, all of which required PLP2 for their K5-mediated downregulation. This work ascribes a critical function to PLP2 for viral ligase activity and underlines the power of non-lethal haploid genetic screens in human cells to identify the genes involved in pathogen manipulation of the host immune system.

  5. High-throughput strategy for molecular identification of Vel- blood donors employing nucleic acids extracted from plasma pools used for viral nucleic acid test screening.

    Science.gov (United States)

    Dezan, Marcia R; Dinardo, Carla L; Bosi, Silvia R A; Vega, Sileni; Salles, Nanci A; Mendrone-Júnior, Alfredo; Levi, José E

    2016-06-01

    Serologic methods to determine the Vel- phenotype require the use of rare human antisera and do not allow for many samples to be tested simultaneously, which limits their application as a tool to search for rare donors. This study developed a low-cost molecular screening strategy using real-time polymerase chain reaction (PCR) and DNA, extracted from plasma pools for viral nucleic acid test (NAT) screening, to identify Vel- and Vel+(W) donors. A total of 4680 blood donors from the Brazilian southeast region were genotyped through real-time PCR targeting the 17-nucleotide (c.64_80del) deletion in the SMIM1 gene, which determines the Vel- phenotype, by using remaining nucleic acid from plasma pools of six donors, routinely discarded after the release of viral NAT results. Twenty pools tested reactive and individual testing of samples from reactive pools identified 19 heterozygous donors with the SMIM1*64_80del deletion (0.40%) and one homozygous donor (0.02%). Fourteen of the 19 donors were confirmed as Vel- or Vel+(W) using anti-Vel human antiserum. The DNA pool genotyping strategy using real-time PCR designed to detect the deletion in the SMIM1 gene proved effective and accurate in identifying donors with the Vel- and Vel+(W) phenotypes. The fact that remaining nucleic acid from routine viral NAT screening was used makes this technique economically attractive and definitely superior to the serologic techniques available to search for this rare phenotype. © 2016 AABB.

  6. BSA Nanoparticles for siRNA Delivery: Coating Effects on Nanoparticle Properties, Plasma Protein Adsorption, and In Vitro siRNA Delivery

    Directory of Open Access Journals (Sweden)

    Haran Yogasundaram

    2012-01-01

    Full Text Available Developing vehicles for the delivery of therapeutic molecules, like siRNA, is an area of active research. Nanoparticles composed of bovine serum albumin, stabilized via the adsorption of poly-L-lysine (PLL, have been shown to be potentially inert drug-delivery vehicles. With the primary goal of reducing nonspecific protein adsorption, the effect of using comb-type structures of poly(ethylene glycol (1 kDa, PEG units conjugated to PLL (4.2 and 24 kDa on BSA-NP properties, apparent siRNA release rate, cell viability, and cell uptake were evaluated. PEGylated PLL coatings resulted in NPs with ζ-potentials close to neutral. Incubation with platelet-poor plasma showed the composition of the adsorbed proteome was similar for all systems. siRNA was effectively encapsulated and released in a sustained manner from all NPs. With 4.2 kDa PLL, cellular uptake was not affected by the presence of PEG, but PEG coating inhibited uptake with 24 kDa PLL NPs. Moreover, 24 kDa PLL systems were cytotoxic and this cytotoxicity was diminished upon PEG incorporation. The overall results identified a BSA-NP coating structure that provided effective siRNA encapsulation while reducing ζ-potential, protein adsorption, and cytotoxicity, necessary attributes for in vivo application of drug-delivery vehicles.

  7. Canine adiponectin: cDNA structure, mRNA expression in adipose tissues and reduced plasma levels in obesity.

    Science.gov (United States)

    Ishioka, K; Omachi, A; Sagawa, M; Shibata, H; Honjoh, T; Kimura, K; Saito, M

    2006-04-01

    Adiponectin is a protein synthesized and secreted by adipocytes. Decreased adiponectin is responsible for insulin resistance and atherosclerosis associated with human obesity. We obtained a cDNA clone corresponding to canine adiponectin, whose nucleotide and deduced amino acid sequences were highly identical to those of other species. Adiponectin mRNA was detected in adipose tissues, but not in other tissues, of dogs. When 22 adult beagles were given a high-energy diet for 14 weeks, they became obese, showing heavier body weights, higher plasma leptin concentrations, but lower plasma adiponectin concentrations. The adiponectin concentrations of plasma samples collected from 71 dogs visiting veterinary practices were negatively correlated to plasma leptin concentrations, being lower in obese than non-obese dogs. These results are compatible with those reported in other species, and suggest that adiponectin is an index of adiposity and a target molecule for studies on diseases associated with obesity in dogs.

  8. Hibiscus Chlorotic Ringspot Virus Coat Protein Is Essential for Cell-to-Cell and Long-Distance Movement but Not for Viral RNA Replication

    Science.gov (United States)

    Niu, Shengniao; Gil-Salas, Francisco M.; Tewary, Sunil Kumar; Samales, Ashwin Kuppusamy; Johnson, John; Swaminathan, Kunchithapadam; Wong, Sek-Man

    2014-01-01

    Hibiscus chlorotic ringspot virus (HCRSV) is a member of the genus Carmovirus in the family Tombusviridae. In order to study its coat protein (CP) functions on virus replication and movement in kenaf (Hibiscus cannabinus L.), two HCRSV mutants, designated as p2590 (A to G) in which the first start codon ATG was replaced with GTG and p2776 (C to G) in which proline 63 was replaced with alanine, were constructed. In vitro transcripts of p2590 (A to G) were able to replicate to a similar level as wild type without CP expression in kenaf protoplasts. However, its cell-to-cell movement was not detected in the inoculated kenaf cotyledons. Structurally the proline 63 in subunit C acts as a kink for β-annulus formation during virion assembly. Progeny of transcripts derived from p2776 (C to G) was able to move from cell-to-cell in inoculated cotyledons but its long-distance movement was not detected. Virions were not observed in partially purified mutant virus samples isolated from 2776 (C to G) inoculated cotyledons. Removal of the N-terminal 77 amino acids of HCRSV CP by trypsin digestion of purified wild type HCRSV virions resulted in only T = 1 empty virus-like particles. Taken together, HCRSV CP is dispensable for viral RNA replication but essential for cell-to-cell movement, and virion is required for the virus systemic movement. The proline 63 is crucial for HCRSV virion assembly in kenaf plants and the N-terminal 77 amino acids including the β-annulus domain is required in T = 3 assembly in vitro. PMID:25402344

  9. Hibiscus chlorotic ringspot virus coat protein is essential for cell-to-cell and long-distance movement but not for viral RNA replication.

    Directory of Open Access Journals (Sweden)

    Shengniao Niu

    Full Text Available Hibiscus chlorotic ringspot virus (HCRSV is a member of the genus Carmovirus in the family Tombusviridae. In order to study its coat protein (CP functions on virus replication and movement in kenaf (Hibiscus cannabinus L., two HCRSV mutants, designated as p2590 (A to G in which the first start codon ATG was replaced with GTG and p2776 (C to G in which proline 63 was replaced with alanine, were constructed. In vitro transcripts of p2590 (A to G were able to replicate to a similar level as wild type without CP expression in kenaf protoplasts. However, its cell-to-cell movement was not detected in the inoculated kenaf cotyledons. Structurally the proline 63 in subunit C acts as a kink for β-annulus formation during virion assembly. Progeny of transcripts derived from p2776 (C to G was able to move from cell-to-cell in inoculated cotyledons but its long-distance movement was not detected. Virions were not observed in partially purified mutant virus samples isolated from 2776 (C to G inoculated cotyledons. Removal of the N-terminal 77 amino acids of HCRSV CP by trypsin digestion of purified wild type HCRSV virions resulted in only T = 1 empty virus-like particles. Taken together, HCRSV CP is dispensable for viral RNA replication but essential for cell-to-cell movement, and virion is required for the virus systemic movement. The proline 63 is crucial for HCRSV virion assembly in kenaf plants and the N-terminal 77 amino acids including the β-annulus domain is required in T = 3 assembly in vitro.

  10. Centrifugation: an important pre-analytic procedure that influences plasma microRNA quantification during blood processing.

    Science.gov (United States)

    Zheng, Xiao-Hui; Cui, Cui; Zhou, Xin-Xi; Zeng, Yi-Xin; Jia, Wei-Hua

    2013-12-01

    Circulating microRNAs are robustly present in plasma or serum and have become a research focus as biomarkers for tumor diagnosis and prognosis. Centrifugation is a necessary procedure for obtaining high-quality blood supernatant. Herein, we investigated one-step and two-step centrifugations, two centrifugal methods routinely used in microRNA study, to explore their effects on plasma microRNA quantification. The microRNAs obtained from one-step and two-step centrifugations were quantified by microarray and TaqMan-based real-time quantitative polymerase chain reaction (Q-PCR). Dynamic light scattering was performed to explore the difference underlying the two centrifugal methods. The results from the microarray containing 1,347 microRNAs showed that the signal detection rate was greatly decreased in the plasma sample prepared by two-step centrifugation. More importantly, the microRNAs missing in this plasma sample could be recovered and detected in the precipitate generated from the second centrifugation. Consistent with the results from microarray, a marked decrease of three representative microRNAs in two-step centrifugal plasma was validated by Q-PCR. According to the size distribution of all nanoparticles in plasma, there were fewer nanoparticles with size >1,000 nm in two-step centrifugal plasma. Our experiments directly demonstrated that different centrifugation methods produced distinct quantities of plasma microRNAs. Thus, exosomes or protein complexes containing microRNAs may be involved in large nanoparticle formation and may be precipitated after two-step centrifugation. Our results remind us that sample processing methods should be first considered in conducting research.

  11. Predictors of undetectable plasma viral load in HIV-positive adults receiving antiretroviral therapy in Southern Brazil

    Directory of Open Access Journals (Sweden)

    Marysabel Pinto Telis Silveira

    Full Text Available Factors associated with undetectable viral load ( or = 95% of adherence (CI 95% 1,80-13,28; CI 95% 1,73-9,53, compared with less than 60% adherence; it was greater for less than 6 months in treatment (OR = 3.37; CI 95% 1.09-10.46; and smaller for viral load previous to adherence measurement > or = 5.2 log10 (OR = 0.19; CI95% 0.06-0.58, adjusted for these variables and sex, age, clinical status, current immune status, group of drugs and interval between the two measurements of viral load. The crude odds were lower for age 16-24 years and use of Nucleoside Analog Reverse Transcriptase Inhibitors only, but these effects were not significant in the multivariate model. There was no evidence of effect of sex, clinical status, current immune status, and changes in treatment regimen. Treatment adherence gave the largest effect. Motivational interventions directed at adherence may improve treatment effectiveness.

  12. Identification of Suitable Endogenous Normalizers for qRT- PCR Analysis of Plasma microRNA Expression in Essential Hypertension

    Science.gov (United States)

    Solayman, Mohamed Hassan M.; Langaee, Taimour; Patel, Archanakumari; El-Wakeel, Lamia; El-Hamamsy, Manal; Badary, Osama; Johnson, Julie A.

    2016-01-01

    Circulating microRNAs (miRNAs) are promising biomarkers for many diseases. Quantitative reverse transcription polymerase chain reaction (qRT-PCR) is a gold standard for miRNA expression profiling that requires proper data normalization. Since there is no universal normalizer, it is recommended to evaluate normalizers under every experimental condition. This study describes the identification of suitable endogenous normalizer(s) (ENs) for plasma miRNA expression in essential hypertension. Expression levels of 5 candidate ENs and 2 plasma quality markers were determined by qRT-PCR in plasma samples from 18 hypertensive patients and 10 healthy controls. NormFinder, GeNorm, and DataAssist software programs were used to select the best EN(s). Expression levels of the 5 candidate ENs were also analyzed in urine samples from hypertensive patients and compared to the plasma samples of the hypertensive patients. Among the analyzed candidates, hsa-miR-92a-3p was identified as the best EN, and hsa-miR-21-5p and hsa-miR-16-5p as next best. Moreover, hsa-miR-92a-3p showed the most consistent expression between plasma and urine In conclusion, this study showed that hsa-miR-92a-3p, hsa-miR-21-5p, and hsa-miR-16-5p may be used as normalizers for plasma miRNA expression data in essential hypertension studies. PMID:26798072

  13. Biochemical and muscle studies in patients with acute onset post-viral fatigue syndrome.

    OpenAIRE

    Preedy, V R; Smith, D G; Salisbury, J R; Peters, T J

    1993-01-01

    AIMS--To investigate in detail various biochemical and pathophysiological indices of muscle pathology in acute onset post-viral fatigue syndrome (PVFS). METHODS--Twenty three patients with PVFS (of mean duration 4.6 years) were subjected to needle biopsy for histomorphometry and total RNA contents. Plasma analysis included serology and creatine kinase activities. Indices of whole body mass were also measured--namely, whole body potassium content and plasma carnosinase activities. RESULTS--Abo...

  14. HIV-1 viral escape in cerebrospinal fluid of subjects on suppressive antiretroviral treatment.

    Science.gov (United States)

    Edén, Arvid; Fuchs, Dietmar; Hagberg, Lars; Nilsson, Staffan; Spudich, Serena; Svennerholm, Bo; Price, Richard W; Gisslén, Magnus

    2010-12-15

    Occasional cases of viral escape in cerebrospinal fluid (CSF) despite suppression of plasma human immunodeficiency virus type 1 (HIV-1) RNA have been reported. We investigated CSF viral escape in subjects treated with commonly used antiretroviral therapy regimens in relation to intrathecal immune activation and central nervous system penetration effectiveness (CPE) rank. Sixty-nine neurologically asymptomatic subjects treated with antiretroviral therapy >6 months and plasma HIV-1 RNA penetration effectiveness rank was not a significant predictor of detectable CSF virus or CSF neopterin levels. Viral escape in CSF is more common than previously reported, suggesting that low-grade central nervous system infection may continue in treated patients. Although these findings need extension in longitudinal studies, they suggest the utility of monitoring CSF responses, as new treatment combinations and strategies modify clinical practice.

  15. Viral Meningitis

    Science.gov (United States)

    ... better from treatment such as an antiviral medicine. Antibiotics do not help viral infections, so they are not useful in the treatment of viral meningitis. However, antibiotics do fight bacteria, so they are very important ...

  16. Pharyngitis - viral

    Science.gov (United States)

    ... throat is due to a viral infection. The antibiotics will not help. Using them to treat viral infections helps bacteria become resistant to antibiotics. With some sore throats (such as those caused ...

  17. Small RNA Profiling in Dengue Virus 2-Infected Aedes Mosquito Cells Reveals Viral piRNAs and Novel Host miRNAs

    NARCIS (Netherlands)

    Miesen, P.; Ivens, A.; Buck, A.H.; Rij, R.P. van

    2016-01-01

    In Aedes mosquitoes, infections with arthropod-borne viruses (arboviruses) trigger or modulate the expression of various classes of viral and host-derived small RNAs, including small interfering RNAs (siRNAs), PIWI interacting RNAs (piRNAs), and microRNAs (miRNAs). Viral siRNAs are at the core of

  18. Introduction of enteral food increases plasma GLP-2 and decreases GLP-2 receptor mRNA abundance during pig development

    DEFF Research Database (Denmark)

    Petersen, Y. M.; Hartmann, B.; Holst, Jens Juul

    2003-01-01

    increased before birth, peaked in suckling 1-d-old pigs (87 +/- 14 pmol/L, P anorexia (34 +/- 5 pmol/L, P ... in these pigs. We conclude that the introduction of enteral feeding transiently increases plasma GLP-2 concentrations and decreases small intestinal GLP-2R mRNA levels during pig development. GLP-2 may play a role in the growth of the small intestine around birth and weaning via a response to enteral nutrition....

  19. Interaction of the host protein NbDnaJ with Potato virus X minus-strand stem-loop 1 RNA and capsid protein affects viral replication and movement.

    Science.gov (United States)

    Cho, Sang-Yun; Cho, Won Kyong; Sohn, Seong-Han; Kim, Kook-Hyung

    2012-01-06

    Plant viruses must interact with host cellular components to replicate and move from cell to cell. In the case of Potato virus X (PVX), it carries stem-loop 1 (SL1) RNA essential for viral replication and movement. Using two-dimensional electrophoresis northwestern blot analysis, we previously identified several host proteins that bind to SL1 RNA. Of those, we further characterized a DnaJ-like protein from Nicotiana benthamiana named NbDnaJ. An electrophoretic mobility shift assay confirmed that NbDnaJ binds only to SL1 minus-strand RNA, and bimolecular fluorescence complementation (BiFC) indicated that NbDnaJ interacts with PVX capsid protein (CP). Using a series of deletion mutants, the C-terminal region of NbDnaJ was found to be essential for the interaction with PVX CP. The expression of NbDnaJ significantly changed upon infection with different plant viruses such as PVX, Tobacco mosaic virus, and Cucumber mosaic virus, but varied depending on the viral species. In transient experiments, both PVX replication and movement were inhibited in plants that over-expressed NbDnaJ but accelerated in plants in which NbDnaJ was silenced. In summary, we suggest that the newly identified NbDnaJ plays a role in PVX replication and movement by interacting with SL1(-) RNA and PVX CP. Copyright © 2011 Elsevier Inc. All rights reserved.

  20. Assessment of six commercial plasma small RNA isolation kits using qRT-PCR and electrophoretic separation

    DEFF Research Database (Denmark)

    Meerson, Ari; Ploug, Thorkil

    2016-01-01

    of specific miRNAs in different samples varied considerably between the tested extraction methods. Of all kits tested, the QIAGEN miRNeasy kits (Mini and Serum/Plasma kits) and the Macherey-Nagel NucleoSpin kit produced the highest RNA yields. The QIAGEN Exo kit produced lesser yields than what could...... be extracted from the UC fraction using the QIAGEN miRNeasy kits and the Macherey-Nagel NucleoSpin kit. Bioanalyzer results showed an average correlation of R2¼0.8 with endogenous miRNA qRT-PCR results, for sample concentrations >40 pg/ml. The levels of the endogenous miRNAs measured in the two volunteer...... samples were compared with those in a larger group of subjects (n¼10) and found to be typical. Our comparison favors the use of the QIAGEN Serum/Plasma kit and the Macherey-Nagel NucleoSpin kit for plasma miRNA applications. Furthermore, extraction of miRNAs from the UC fraction results in higher yield...

  1. Plasma microRNA-451 as a novel hemolytic marker for β0-thalassemia/HbE disease

    Science.gov (United States)

    Leecharoenkiat, Kamonlak; Tanaka, Yuka; Harada, Yasuko; Chaichompoo, Porntip; Sarakul, Orawan; Abe, Yasunobu; Smith, Duncan Richard; Fucharoen, Suthat; Svasti, Saovaros; Umemura, Tsukuru

    2017-01-01

    In Southeast Asia, particularly in Thailand, β0-thalassemia/hemoglobin E (HbE) disease is a common hereditary hematological disease. It is associated with pathophysiological processes, such as the intramedullary destruction of immature erythroid cells and peripheral hemolysis of mature red blood cells. MicroRNA (miR) sequences, which are short non-coding RNA that regulate gene expression in a suppressive manner, serve a crucial role in human erythropoiesis. In the present study, the plasma levels of the erythroid-expressed miRNAs, miR-451 and miR-155, were analyzed in 23 patients with β0-thalassemia/HbE and 16 control subjects. Reverse transcription-quantitative polymerase chain reaction analysis revealed significantly higher levels of plasma miR-451 and miR-155 in β0-thalassemia/HbE patients when compared to the control subjects. Notably, among the β0-thalassemia/HbE patients, a significant increase in miR-451 levels was detected in severe cases when compared with mild cases. The levels of plasma miR-451 correlated with reticulocyte and platelet counts. The results suggest that increased plasma miR-451 levels may be associated with the degree of hemolysis and accelerated erythropoiesis in β0-thalassemia/HbE patients. In conclusion, miR-451 may represent a relevant biomarker for pathological erythropoiesis associated with β0-thalassemia/HbE. PMID:28447765

  2. Viral CTL escape mutants are generated in lymph nodes and subsequently become fixed in plasma and rectal mucosa during acute SIV infection of macaques.

    Directory of Open Access Journals (Sweden)

    Thomas H Vanderford

    2011-05-01

    Full Text Available SIV(mac239 infection of rhesus macaques (RMs results in AIDS despite the generation of a strong antiviral cytotoxic T lymphocyte (CTL response, possibly due to the emergence of viral escape mutants that prevent recognition of infected cells by CTLs. To determine the anatomic origin of these SIV mutants, we longitudinally assessed the presence of CTL escape variants in two MamuA*01-restricted immunodominant epitopes (Tat-SL8 and Gag-CM9 in the plasma, PBMCs, lymph nodes (LN, and rectal biopsies (RB of fifteen SIV(mac239-infected RMs. As expected, Gag-CM9 did not exhibit signs of escape before day 84 post infection. In contrast, Tat-SL8 escape mutants were apparent in all tissues by day 14 post infection. Interestingly LNs and plasma exhibited the highest level of escape at day 14 and day 28 post infection, respectively, with the rate of escape in the RB remaining lower throughout the acute infection. The possibility that CTL escape occurs in LNs before RBs is confirmed by the observation that the specific mutants found at high frequency in LNs at day 14 post infection became dominant at day 28 post infection in plasma, PBMC, and RB. Finally, the frequency of escape mutants in plasma at day 28 post infection correlated strongly with the level Tat-SL8-specific CD8 T cells in the LN and PBMC at day 14 post infection. These results indicate that LNs represent the primary source of CTL escape mutants during the acute phase of SIV(mac239 infection, suggesting that LNs are the main anatomic sites of virus replication and/or the tissues in which CTL pressure is most effective in selecting SIV escape variants.

  3. Daily rhythms of plasma melatonin, but not plasma leptin or leptin mRNA, vary between lean, obese and type 2 diabetic men.

    Directory of Open Access Journals (Sweden)

    Simone Mäntele

    Full Text Available Melatonin and leptin exhibit daily rhythms that may contribute towards changes in metabolic physiology. It remains unclear, however, whether this rhythmicity is altered in obesity or type 2 diabetes (T2DM. We tested the hypothesis that 24-hour profiles of melatonin, leptin and leptin mRNA are altered by metabolic status in laboratory conditions. Men between 45-65 years old were recruited into lean, obese-non-diabetic or obese-T2DM groups. Volunteers followed strict sleep-wake and dietary regimes for 1 week before the laboratory study. They were then maintained in controlled light-dark conditions, semi-recumbent posture and fed hourly iso-energetic drinks during wake periods. Hourly blood samples were collected for hormone analysis. Subcutaneous adipose biopsies were collected 6-hourly for gene expression analysis. Although there was no effect of subject group on the timing of dim light melatonin onset (DLMO, nocturnal plasma melatonin concentration was significantly higher in obese-non-diabetic subjects compared to weight-matched T2DM subjects (p<0.01 and lean controls (p<0.05. Two T2DM subjects failed to produce any detectable melatonin, although did exhibit plasma cortisol rhythms comparable to others in the group. Consistent with the literature, there was a significant (p<0.001 effect of subject group on absolute plasma leptin concentration and, when expressed relative to an individual's 24-hour mean, plasma leptin showed significant (p<0.001 diurnal variation. However, there was no difference in amplitude or timing of leptin rhythms between experimental groups. There was also no significant effect of time on leptin mRNA expression. Despite an overall effect (p<0.05 of experimental group, post-hoc analysis revealed no significant pair-wise effects of group on leptin mRNA expression. Altered plasma melatonin rhythms in weight-matched T2DM and non-diabetic individuals supports a possible role of melatonin in T2DM aetiology. However, neither

  4. Correlation of mRNA Profiles, miRNA Profiles, and Functional Immune Response in Rainbow Trout (Oncorrhynkus Mykiss) Infected With Viral Hemorrhagic Septicemia Virus (VHSV) and in Fish Vaccinated With a DNA Vaccine Against VHSV

    DEFF Research Database (Denmark)

    Bela-Ong, Dennis; Schyth, Brian Dall; Jørgensen, Hanne

    2011-01-01

    and are incorporated into the RNA-Induced Silencing Complex (RISC), which target specific mRNA sequences, causing either mRNA degradation or translation repression. This results in altered mRNA and protein profiles characteristic of a particular cellular phenotype or physiological state. By targeting immune relevant m...

  5. Relationship between expression of leptin receptors mRNA in breast tissue, plasma leptin level in breast cancer patients with obesity and clinical pathologic data

    International Nuclear Information System (INIS)

    Li Chunrui; Liu Wenli; Sun Hanying; Zhou Jianfeng

    2007-01-01

    In order to investigate the expression of leptin receptors mRNA in breast tissue and plasma leptin levels in breast cancer patients with obesity and their relationship with clinical pathologic data, 124 subjects who were either obesity or had suffered from breast benign disease with obesity, or breast cancer with obesity were entered into this study. The levels of plasma leptin in all subjects were determined and leptin receptors mRNA expression levels were measured by RT-PCR in breast tissue of breast cancer patients with obesity and breast benign disease with obesity. The results showed that plasma leptin levels in breast cancer patients with obesity were significantly higher than those in breast benign disease with obesity and obesity patients alone (P<0.05). The expression of the leptin receptor long form [-Lep-R(L)-] mRNA and the leptin receptor short form [-Lep-R(S)-] mRNA in breast tissue of breast cancer patients with obesity were significantly higher than that in breast tissue of breast benign disease patients with obesity (P<0.05). The plasma leptin level had remarkable positive correlation with the expressions of the Lep-R(L) mRNA and the Lep-R(S) mRNA. The plasma leptin level and leptin receptors mRNA expression levels in patients were not correlated with the axillary node metastasis, menopause, the TNM stage or pathological type. Therefore, leptin may have a promoting effect on the carcinogenesis of breast cancer. (authors)

  6. Prognosis of patients treated with cART from 36 months after initiation, according to current and previous CD4 cell count and plasma HIV-1 RNA measurements

    NARCIS (Netherlands)

    Lanoy, Emilie; May, Margaret; Mocroft, Amanda; Phillips, Andrew; Justice, Amy; Chene, Genevieve; Furrer, Hansjakob; Sterling, Timothy; D'Arminio Monforte, Antonella; Force, Lluis; Gill, John; Harris, Ross; Hogg, Robert S.; Rockstroh, Juergen; Saag, Mike; Khaykin, Pavel; de Wolf, Frank; Sterne, Jonathan A. C.; Costagliola, Dominique

    2009-01-01

    Objectives: CD4 cell count and plasma viral load are well known predictors of AIDS and mortality in HIV-1-infected patients treated with combination antiretroviral therapy (cART). This study investigated, in patients treated for at least 3 years, the respective prognostic importance of values

  7. Analytical and clinical performance of the Hologic Aptima HCV Quant Dx Assay for the quantification of HCV RNA in plasma samples

    DEFF Research Database (Denmark)

    Schønning, Kristian; Pedersen, Martin Schou; Johansen, Kim

    2017-01-01

    obtained from 13 patients undergoing treatment with DAAs. RESULTS: Deming regression of results from 187 plasma samples with HCV RNA >2 Log IU/mL indicated that the Aptima assay quantified higher than the CAPCTMv2 test for HCV RNA >4.9 Log IU/mL. The linearity of the Aptima assay was excellent across...

  8. Exercise increases the plasma membrane content of the Na+ -K+ pump and its mRNA in rat skeletal muscles.

    Science.gov (United States)

    Tsakiridis, T; Wong, P P; Liu, Z; Rodgers, C D; Vranic, M; Klip, A

    1996-02-01

    Muscle fibers adapt to ionic challenges of exercise by increasing the plasma membrane Na+-K+ pump activity. Chronic exercise training has been shown to increase the total amount of Na+-K+ pumps present in skeletal muscle. However, the mechanism of adaptation of the Na+-K+ pump to an acute bout of exercise has not been determined, and it is not known whether it involves alterations in the content of plasma membrane pump subunits. Here we examine the effect of 1 h of treadmill running (20 m/min, 10% grade) on the subcellular distribution and expression of Na+-K+ pump subunits in rat skeletal muscles. Red type I and IIa (red-I/IIa) and white type IIa and IIb (white-IIa/IIb) hindlimb muscles from resting and exercised female Sprague-Dawley rats were removed for subcellular fractionation. By homogenization and gradient centrifugation, crude membranes and purified plasma membranes were isolated and subjected to gel electrophoresis and immunoblotting by using pump subunit-specific antibodies. Furthermore, mRNA was isolated from specific red type I (red-I) and white type IIb (white-IIb) muscles and subjected to Northern blotting by using subunit-specific probes. In both red-I/IIa and white-IIa/IIb muscles, exercise significantly raised the plasma membrane content of the alpha1-subunit of the pump by 64 +/- 24 and 55 +/- 22%, respectively (P < 0.05), and elevated the alpha2-polypeptide by 43 +/- 22 and 94 +/- 39%, respectively (P < 0.05). No significant effect of exercise could be detected on the amount of these subunits in an internal membrane fraction or in total membranes. In addition, exercise significantly increased the alpha1-subunit mRNA in red-I muscle (by 50 +/- 7%; P < 0.05) and the beta2-subunit mRNA in white-IIb muscles (by 64 +/- 19%; P < 0.01), but the alpha2- and beta1-mRNA levels were unaffected in this time period. We conclude that increased presence of alpha1- and alpha2-polypeptides at the plasma membrane and subsequent elevation of the alpha1- and beta2

  9. Cytomegalovirus sequence variability, amplicon length, and DNase-sensitive non-encapsidated genomes are obstacles to standardization and commutability of plasma viral load results.

    Science.gov (United States)

    Naegele, Klaudia; Lautenschlager, Irmeli; Gosert, Rainer; Loginov, Raisa; Bir, Katia; Helanterä, Ilkka; Schaub, Stefan; Khanna, Nina; Hirsch, Hans H

    2018-04-22

    Cytomegalovirus (CMV) management post-transplantation relies on quantification in blood, but inter-laboratory and inter-assay variability impairs commutability. An international multicenter study demonstrated that variability is mitigated by standardizing plasma volumes, automating DNA extraction and amplification, and calibration to the 1st-CMV-WHO-International-Standard as in the FDA-approved Roche-CAP/CTM-CMV. However, Roche-CAP/CTM-CMV showed under-quantification and false-negative results in a quality assurance program (UK-NEQAS-2014). To evaluate factors contributing to quantification variability of CMV viral load and to develop optimized CMV-UL54-QNAT. The UL54 target of the UK-NEQAS-2014 variant was sequenced and compared to 329 available CMV GenBank sequences. Four Basel-CMV-UL54-QNAT assays of 361 bp, 254 bp, 151 bp, and 95 bp amplicons were developed that only differed in reverse primer positions. The assays were validated using plasmid dilutions, UK-NEQAS-2014 sample, as well as 107 frozen and 69 prospectively collected plasma samples from transplant patients submitted for CMV QNAT, with and without DNase-digestion prior to nucleic acid extraction. Eight of 43 mutations were identified as relevant in the UK-NEQAS-2014 target. All Basel-CMV-UL54 QNATs quantified the UK-NEQAS-2014 but revealed 10-fold increasing CMV loads as amplicon size decreased. The inverse correlation of amplicon size and viral loads was confirmed using 1st-WHO-International-Standard and patient samples. DNase pre-treatment reduced plasma CMV loads by >90% indicating the presence of unprotected CMV genomic DNA. Sequence variability, amplicon length, and non-encapsidated genomes obstruct standardization and commutability of CMV loads needed to develop thresholds for clinical research and management. Besides regular sequence surveys, matrix and extraction standardization, we propose developing reference calibrators using 100 bp amplicons. Copyright © 2018 Elsevier B.V. All

  10. Plasma cytokines do not reflect expression of pro- and anti-inflammatory cytokine mRNA at organ level after cardiopulmonary bypass in neonatal pigs

    DEFF Research Database (Denmark)

    Brix-Christensen, V.; Vestergaard, C.; Chew, M.

    2003-01-01

    Background: Plasma concentrations of inflammatory markers are increased in response to the trauma of cardiac surgery and cardiopulmonary bypass (CPB). It is, however, unknown whether the plasma cytokine levels and cytokine mRNA expression at organ level reflect each other. Methods: Twenty...

  11. A study of the dimer formation of Rous sarcoma virus RNA and of its effect on viral protein synthesis in vitro.

    Science.gov (United States)

    Bieth, E; Gabus, C; Darlix, J L

    1990-01-11

    The genetic material of all retroviruses examined so far is an RNA dimer where two identical RNA subunits are joined at their 5' ends by a structure named dimer linkage structure (DLS). Since the precise location and structure of the DLS as well as the mechanism and role(s) of RNA dimerization remain unclear, we analysed the dimerization process of Rous sarcoma virus (RSV) RNA. For this purpose we set up an in vitro model for RSV RNA dimerization. Using this model RSV RNA was shown to form dimeric molecules and this dimerization process was greatly activated by nucleocapsid protein (NCp12) of RSV. Furthermore, RSV RNA dimerization was performed in the presence of complementary 5'32P-DNA oligomers in order to probe the monomer and dimer forms of RSV RNA. Data indicated that the DLS of RSV RNA probably maps between positions 544-564 from the 5' end. In an attempt to define sequences needed for the dimerization of RSV RNA, deletion mutageneses were generated in the 5' 600 nt. The results showed that the dimer promoting sequences probably are located within positions 208-270 and 400-600 from the 5' end and hence possibly encompassing the cis-acting elements needed for the specific encapsidation of RSV genomic RNA. Also it is reported that synthesis of the polyprotein precursor Pr76gag is inhibited upon dimerization of RSV RNA. These results suggest that dimerization and encapsidation of genome length RSV RNA might be linked in the course of virion formation since they appear to be under the control of the same cis elements, E and DLS, and the trans-acting factor nucleocapsid protein NCp12.

  12. Multiplexed microRNA detection using lanthanide-labeled DNA probes and laser ablation inductively coupled plasma mass spectrometry

    DEFF Research Database (Denmark)

    de Bang, Thomas Christian; Shah, Pratik; Cho, Seok Keun

    2014-01-01

    coupled plasma mass spectrometry (LA-ICPMS). Three miRNAs from Arabidopsis thaliana were analyzed simultaneously with high specificity, and the sensitivity of the method was comparable to radioactive detection (low femtomol range). The perspective of the developed method is highly multiplexed......In the past decade, microRNAs (miRNAs) have drawn increasing attention due to their role in regulation of gene expression. Especially, their potential as biomarkers in disease diagnostics has motivated miRNA research, including the development of simple, accurate, and sensitive detection methods....... The narrow size range of miRNAs (20-24 nucleotides) combined with the chemical properties of conventional reporter tags has hampered the development of multiplexed miRNA assays. In this study, we have used lanthanide-labeled DNA probes for the detection of miRNAs on membranes using laser ablation inductively...

  13. Complement lysis activity in autologous plasma is associated with lower viral loads during the acute phase of HIV-1 infection.

    Directory of Open Access Journals (Sweden)

    Michael Huber

    2006-11-01

    Full Text Available BACKGROUND: To explore the possibility that antibody-mediated complement lysis contributes to viremia control in HIV-1 infection, we measured the activity of patient plasma in mediating complement lysis of autologous primary virus. METHODS AND FINDINGS: Sera from two groups of patients-25 with acute HIV-1 infection and 31 with chronic infection-were used in this study. We developed a novel real-time PCR-based assay strategy that allows reliable and sensitive quantification of virus lysis by complement. Plasma derived at the time of virus isolation induced complement lysis of the autologous virus isolate in the majority of patients. Overall lysis activity against the autologous virus and the heterologous primary virus strain JR-FL was higher at chronic disease stages than during the acute phase. Most strikingly, we found that plasma virus load levels during the acute but not the chronic infection phase correlated inversely with the autologous complement lysis activity. Antibody reactivity to the envelope (Env proteins gp120 and gp41 were positively correlated with the lysis activity against JR-FL, indicating that anti-Env responses mediated complement lysis. Neutralization and complement lysis activity against autologous viruses were not associated, suggesting that complement lysis is predominantly caused by non-neutralizing antibodies. CONCLUSIONS: Collectively our data provide evidence that antibody-mediated complement virion lysis develops rapidly and is effective early in the course of infection; thus it should be considered a parameter that, in concert with other immune functions, steers viremia control in vivo.

  14. Adipose tissue interleukin-18 mRNA and plasma interleukin-18: effect of obesity and exercise

    DEFF Research Database (Denmark)

    Leick, Lotte; Lindegaard, Birgitte; Stensvold, Dorthe

    2007-01-01

    resistance was tested. Furthermore, we speculated that acute exercise and exercise training would regulate AT IL-18 mRNA expression. RESEARCH METHODS AND PROCEDURES: Non-obese subjects with BMI women: n = 18; men; n = 11) and obese subjects with BMI >30 kg/m(2) (women: n = 6; men: n = 7...... of regular physical activity with improved insulin sensitivity.......OBJECTIVES: Obesity and a physically inactive lifestyle are associated with increased risk of developing insulin resistance. The hypothesis that obesity is associated with increased adipose tissue (AT) interleukin (IL)-18 mRNA expression and that AT IL-18 mRNA expression is related to insulin...

  15. Bacterial vaginosis, human papilloma virus and herpes viridae do not predict vaginal HIV RNA shedding in women living with HIV in Denmark

    DEFF Research Database (Denmark)

    Wessman, Maria; Thorsteinsson, Kristina; Jensen, Jørgen S

    2017-01-01

    in the genital tract despite undetectable HIV RNA plasma viral load. We examined the prevalence and diagnostic predictors of BV and HIV-1 RNA vaginal shedding in women living with HIV (WLWH) in Denmark, taking into account the presence of human papillomavirus (HPV) and herpes viridae. Methods: WLWH between 18...

  16. Correlation of mRNA Profiles, miRNA Profiles, and Functional Immune Response in Rainbow Trout (Oncorrhynkus Mykiss) During Infection With Viral Hemorrhagic Septicemia Virus (VHSV) and in Fish Vaccinated With an Anti-VHSV DNA Vaccine

    DEFF Research Database (Denmark)

    Bela-Ong, Dennis; Schyth, Brian Dall; Lorenzen, Niels

    fish. Linking mRNA and miRNA profiles with phenotypic, genotypic, and immunological data will provide an integrated view of the mechanisms of resistance and the strong protective immune responses provided by vaccination. This information is important in designing effective strategies to mitigate......-mediated) responses. MRNA and miRNA profiles will be correlated and combined with in vitro work in cell culture to describe target relationships between miRNAs and mRNAs and the effect of this targeting in fish. Vaccinated fish will also be used for mRNA/miRNA profiling and in challenge studies alongside non-vaccinated...

  17. Viral dsRNA-activated human dendritic cells produce IL-27, which selectively promotes cytotoxicity in naive CD8(+) T cells

    NARCIS (Netherlands)

    de Groot, Rosa; van Beelen, Astrid J.; Bakdash, Ghaith; Taanman-Kueter, Esther W. M.; de Jong, Esther C.; Kapsenberg, Martien L.

    2012-01-01

    Viral recognition programs DCs to express Signal 3 molecules that promote the differentiation of effector CD8(+) T cells. Besides IL-12, another DC-derived IL-12 family member, IL-27, has been reported to contribute herein, but its specific role is not well understood. Here, we show that whereas

  18. Adeno-Associated Viral Vector-Mediated mTOR Inhibition by Short Hairpin RNA Suppresses Laser-Induced Choroidal Neovascularization

    Directory of Open Access Journals (Sweden)

    Tae Kwann Park

    2017-09-01

    Full Text Available Choroidal neovascularization (CNV is the defining characteristic feature of the wet subtype of age-related macular degeneration (AMD and may result in irreversible blindness. Based on anti-vascular endothelial growth factor (anti-VEGF, the current therapeutic approaches to CNV are fraught with difficulties, and mammalian target of rapamycin (mTOR has recently been proposed as a possible therapeutic target, although few studies have been conducted. Here, we show that a recombinant adeno-associated virus-delivered mTOR-inhibiting short hairpin RNA (rAAV-mTOR shRNA, which blocks the activity of both mTOR complex 1 and 2, represents a promising therapeutic approach for the treatment of CNV. Eight-week-old male C57/B6 mice were treated with the short hairpin RNA (shRNA after generating CNV lesions in the eyes via laser photocoagulation. The recombinant adeno-associated virus (rAAV delivery vehicle was able to effectively transduce cells in the inner retina, and significantly fewer inflammatory cells and less extensive CNV were observed in the animals treated with rAAV-mTOR shRNA when compared with control- and rAAV-scrambled shRNA-treated groups. Presumably related to the reduction of CNV, increased autophagy was detected in CNV lesions treated with rAAV-mTOR shRNA, whereas significantly fewer apoptotic cells detected in the outer nuclear layer around the CNV indicate that mTOR inhibition may also have neuroprotective effects. Taken together, these results demonstrate the therapeutic potential of mTOR inhibition, resulting from rAAV-mTOR shRNA activity, in the treatment of AMD-related CNV. Keywords: retinal neovascularization, choroidal neovascularization, adeno-associated virus, mTOR, RNA interference, mTOR shRNA, autophagy

  19. Hamp1 mRNA and plasma hepcidin levels are influenced by sex and strain but do not predict tissue iron levels in inbred mice.

    Science.gov (United States)

    McLachlan, Stela; Page, Kathryn E; Lee, Seung-Min; Loguinov, Alex; Valore, Erika; Hui, Simon T; Jung, Grace; Zhou, Jie; Lusis, Aldons J; Fuqua, Brie; Ganz, Tomas; Nemeth, Elizabeta; Vulpe, Chris D

    2017-11-01

    Iron homeostasis is tightly regulated, and the peptide hormone hepcidin is considered to be a principal regulator of iron metabolism. Previous studies in a limited number of mouse strains found equivocal sex- and strain-dependent differences in mRNA and serum levels of hepcidin and reported conflicting data on the relationship between hepcidin ( Hamp1 ) mRNA levels and iron status. Our aim was to clarify the relationships between strain, sex, and hepcidin expression by examining multiple tissues and the effects of different dietary conditions in multiple inbred strains. Two studies were done: first, Hamp1 mRNA, liver iron, and plasma diferric transferrin levels were measured in 14 inbred strains on a control diet; and second, Hamp1 mRNA and plasma hepcidin levels in both sexes and iron levels in the heart, kidneys, liver, pancreas, and spleen in males were measured in nine inbred/recombinant inbred strains raised on an iron-sufficient or high-iron diet. Both sex and strain have a significant effect on both hepcidin mRNA (primarily a sex effect) and plasma hepcidin levels (primarily a strain effect). However, liver iron and diferric transferrin levels are not predictors of Hamp1 mRNA levels in mice fed iron-sufficient or high-iron diets, nor are the Hamp1 mRNA and plasma hepcidin levels good predictors of tissue iron levels, at least in males. We also measured plasma erythroferrone, performed RNA-sequencing analysis of liver samples from six inbred strains fed the iron-sufficient, low-iron, or high-iron diets, and explored differences in gene expression between the strains with the highest and lowest hepcidin levels. NEW & NOTEWORTHY Both sex and strain have a significant effect on both hepcidin mRNA (primarily a sex effect) and plasma hepcidin levels (primarily a strain effect). Liver iron and diferric transferrin levels are not predictors of Hamp1 mRNA levels in mice, nor are the Hamp1 mRNA and plasma hepcidin levels good predictors of tissue iron levels, at least

  20. Missense mutation in GRN gene affecting RNA splicing and plasma progranulin level in a family affected by frontotemporal lobar degeneration.

    Science.gov (United States)

    Luzzi, Simona; Colleoni, Lara; Corbetta, Paola; Baldinelli, Sara; Fiori, Chiara; Girelli, Francesca; Silvestrini, Mauro; Caroppo, Paola; Giaccone, Giorgio; Tagliavini, Fabrizio; Rossi, Giacomina

    2017-06-01

    Gene coding for progranulin, GRN, is a major gene linked to frontotemporal lobar degeneration. While most of pathogenic GRN mutations are null mutations leading to haploinsufficiency, GRN missense mutations do not have an obvious pathogenicity, and only a few have been revealed to act through different pathogenetic mechanisms, such as cytoplasmic missorting, protein degradation, and abnormal cleavage by elastase. The aim of this study was to disclose the pathogenetic mechanisms of the GRN A199V missense mutation, which was previously reported not to alter physiological progranulin features but was associated with a reduced plasma progranulin level. After investigating the family pedigree, we performed genetic and biochemical analysis on its members and performed RNA expression studies. We found that the mutation segregates with the disease and discovered that its pathogenic feature is the alteration of GRN mRNA splicing, actually leading to haploinsufficiency. Thus, when facing with a missense GRN mutation, its pathogenetic effects should be investigated, especially if associated with low plasma progranulin levels, to determine its nature of either benign polymorphism or pathogenic mutation. Copyright © 2017 Elsevier Inc. All rights reserved.

  1. IP-10 predicts the first phase decline of HCV RNA and overall viral response to therapy in patients co-infected with chronic hepatitis C virus infection and HIV

    DEFF Research Database (Denmark)

    Falconer, Karolin; Askarieh, Galia; Weis, Nina Margrethe

    2010-01-01

    The aim of this study was to investigate the utility of baseline plasma interferon-gamma inducible protein-10 (IP-10) levels in human immunodeficiency virus (HIV)-hepatitis C virus (HCV) co-infected patients. Baseline IP-10 was monitored during HCV combination therapy in 21 HIV-HCV co-infected pa......The aim of this study was to investigate the utility of baseline plasma interferon-gamma inducible protein-10 (IP-10) levels in human immunodeficiency virus (HIV)-hepatitis C virus (HCV) co-infected patients. Baseline IP-10 was monitored during HCV combination therapy in 21 HIV-HCV co......-10 viral response to HCV therapy in HIV-HCV co-infected patients, and may thus be useful in encouraging such difficult-to-treat patients to initiate therapy....

  2. Multiplex real-time PCR for the detection and quantification of latent and persistent viral genomes in cellular or plasma blood fractions.

    Science.gov (United States)

    Compston, Lara Isobel; Sarkobie, Francis; Li, Chengyao; Candotti, Daniel; Opare-Sem, Ohene; Allain, Jean-Pierre

    2008-07-01

    In common with latent viruses such as herpesviruses, parvovirus B19, HBV and GBV-C are contained successfully by the immune response and persist in the host. When immune control breaks down, reactivation of both latent and persistent viruses occurs. Two multiplex assays were developed (B19, HBV, HHV-8), (EBV, CMV, VZV) for blood screening, and tested on blood donor samples from Ghana to determine baseline prevalence of viraemia in immunocompetent persons. Single-virus real-time quantitative PCR (qPCR) assays were optimised for viral load determination of positive initial screening. The qPCR method utilised was absolute quantification with external standards. Multiplex and single-virus qPCR assays had similar sensitivity, except for the B19 assay in which sensitivity was 100-fold lower. Assays were optimised for reproducibility and repeatability, with R(2) of 0.9 being obtained for most assays. With the exception of B19 and CMV, assays had 100% detection limit ranging between 10(1) and 10(2) copies, IU or arbitrary units under single-virus and multiplex assay conditions. The prevalence of viraemia was 1.6% HBV (0.8% DNA+/HBsAg-, 0.8% DNA+/HBsAg+), 0.8% parvovirus B19, and 3.3% GBV-C viraemia in the plasma fraction. The prevalence of four herpesviruses was 1.0% HHV-8, 0.85% CMV, and 8.3% EBV, and no detectable VZV viraemia.

  3. Viral Marketing

    OpenAIRE

    Sorina Raula Gîrboveanu; Silvia Puiu

    2008-01-01

    With consumers showing increasing resistance to traditional forms of advertising such as TV or newspaper ads, marketers have turned to alternate strategies, including viral marketing. Viral marketing exploits existing social networks by encouraging customers to share product information with their friends.In our study we are able to directly observe the effectiveness of person to person word of mouth advertising for hundreds of thousands of products for the first time

  4. Model of OSBP-Mediated Cholesterol Supply to Aichi Virus RNA Replication Sites Involving Protein-Protein Interactions among Viral Proteins, ACBD3, OSBP, VAP-A/B, and SAC1.

    Science.gov (United States)

    Ishikawa-Sasaki, Kumiko; Nagashima, Shigeo; Taniguchi, Koki; Sasaki, Jun

    2018-04-15

    Positive-strand RNA viruses, including picornaviruses, utilize cellular machinery for genome replication. Previously, we reported that each of the 2B, 2BC, 2C, 3A, and 3AB proteins of Aichi virus (AiV), a picornavirus, forms a complex with the Golgi apparatus protein ACBD3 and phosphatidylinositol 4-kinase IIIβ (PI4KB) at viral RNA replication sites (replication organelles [ROs]), enhancing PI4KB-dependent phosphatidylinositol 4-phosphate (PI4P) production. Here, we demonstrate AiV hijacking of the cellular cholesterol transport system involving oxysterol-binding protein (OSBP), a PI4P-binding cholesterol transfer protein. AiV RNA replication was inhibited by silencing cellular proteins known to be components of this pathway, OSBP, the ER membrane proteins VAPA and VAPB (VAP-A/B), the PI4P-phosphatase SAC1, and PI-transfer protein β. OSBP, VAP-A/B, and SAC1 were present at RNA replication sites. We also found various previously unknown interactions among the AiV proteins (2B, 2BC, 2C, 3A, and 3AB), ACBD3, OSBP, VAP-A/B, and SAC1, and the interactions were suggested to be involved in recruiting the component proteins to AiV ROs. Importantly, the OSBP-2B interaction enabled PI4P-independent recruitment of OSBP to AiV ROs, indicating preferential recruitment of OSBP among PI4P-binding proteins. Protein-protein interaction-based OSBP recruitment has not been reported for other picornaviruses. Cholesterol was accumulated at AiV ROs, and inhibition of OSBP-mediated cholesterol transfer impaired cholesterol accumulation and AiV RNA replication. Electron microscopy showed that AiV-induced vesicle-like structures were close to ER membranes. Altogether, we conclude that AiV directly recruits the cholesterol transport machinery through protein-protein interactions, resulting in formation of membrane contact sites between the ER and AiV ROs and cholesterol supply to the ROs. IMPORTANCE Positive-strand RNA viruses utilize host pathways to modulate the lipid composition of

  5. Relationship between Sustained Reductions in Plasma Lipid and Lipoprotein Concentrations with Apheresis and Plasma Levels and mRNA Expression of PTX3 and Plasma Levels of hsCRP in Patients with HyperLp(a)lipoproteinemia

    Science.gov (United States)

    Stefanutti, Claudia; Mazza, Fabio; Steiner, Michael; Watts, Gerald F.; De Nève, Joel; Pasqualetti, Daniela; Paal, Juergen

    2016-01-01

    The effect of lipoprotein apheresis (Direct Adsorption of Lipids, DALI) (LA) on plasma levels of pentraxin 3 (PTX3), an inflammatory marker that reflects coronary plaque vulnerability, and expression of PTX3 mRNA was evaluated in patients with hyperLp(a)lipoproteinemia and angiographically defined atherosclerosis/coronary artery disease. Eleven patients, aged 55 ± 9.3 years (mean ± SD), were enrolled in the study. PTX3 soluble protein levels in plasma were unchanged by 2 sessions of LA; however, a downregulation of mRNA expression for PTX3 was observed, starting with the first session of LA (p < 0.001). The observed reduction was progressively increased in the interval between the first and second LA sessions to achieve a maximum decrease by the end of the second session. A statistically significantly greater treatment-effect correlation was observed in patients undergoing weekly treatments, compared with those undergoing treatment every 15 days. A progressive reduction in plasma levels of C-reactive protein was also seen from the first session of LA, with a statistically significant linear correlation for treatment-effect in the change in plasma levels of this established inflammatory marker (R 2 = 0.99; p < 0.001). Our findings suggest that LA has anti-inflammatory and endothelium protective effects beyond its well-established efficacy in lowering apoB100-containing lipoproteins. PMID:26903710

  6. Relationship between Sustained Reductions in Plasma Lipid and Lipoprotein Concentrations with Apheresis and Plasma Levels and mRNA Expression of PTX3 and Plasma Levels of hsCRP in Patients with HyperLp(alipoproteinemia

    Directory of Open Access Journals (Sweden)

    Claudia Stefanutti

    2016-01-01

    Full Text Available The effect of lipoprotein apheresis (Direct Adsorption of Lipids, DALI (LA on plasma levels of pentraxin 3 (PTX3, an inflammatory marker that reflects coronary plaque vulnerability, and expression of PTX3 mRNA was evaluated in patients with hyperLp(alipoproteinemia and angiographically defined atherosclerosis/coronary artery disease. Eleven patients, aged 55±9.3 years (mean ± SD, were enrolled in the study. PTX3 soluble protein levels in plasma were unchanged by 2 sessions of LA; however, a downregulation of mRNA expression for PTX3 was observed, starting with the first session of LA (p<0.001. The observed reduction was progressively increased in the interval between the first and second LA sessions to achieve a maximum decrease by the end of the second session. A statistically significantly greater treatment-effect correlation was observed in patients undergoing weekly treatments, compared with those undergoing treatment every 15 days. A progressive reduction in plasma levels of C-reactive protein was also seen from the first session of LA, with a statistically significant linear correlation for treatment-effect in the change in plasma levels of this established inflammatory marker (R2=0.99; p<0.001. Our findings suggest that LA has anti-inflammatory and endothelium protective effects beyond its well-established efficacy in lowering apoB100-containing lipoproteins.

  7. Apolipoprotein B knockdown by AAV-delivered shRNA lowers plasma cholesterol in mice

    NARCIS (Netherlands)

    Koornneef, Annemart; Maczuga, Piotr; van Logtenstein, Richard; Borel, Florie; Blits, Bas; Ritsema, Tita; van Deventer, Sander; Petry, Harald; Konstantinova, Pavlina

    2011-01-01

    Serum low-density lipoprotein cholesterol (LDL-C) levels are proportionate to the risk of atherosclerotic cardiovascular disease. In order to reduce serum total cholesterol and LDL-C levels in mice, RNA interference (RNAi) was used to inhibit expression of the structural protein of LDL-C,

  8. The miRNA Plasma Signature in Response to Acute Aerobic Exercise and Endurance Training

    DEFF Research Database (Denmark)

    Nielsen, Søren; Åkerström, Thorbjörn; Rinnov, Anders

    2014-01-01

    MiRNAs are potent intracellular posttranscriptional regulators and are also selectively secreted into the circulation in a cell-specific fashion. Global changes in miRNA expression in skeletal muscle in response to endurance exercise training have been reported. Therefore, our aim was to establis...

  9. Analysis of plasma microRNA expression profiles in male textile workers with noise-induced hearing loss.

    Science.gov (United States)

    Ding, Lu; Liu, Jing; Shen, Huan-Xi; Pan, Li-Ping; Liu, Qing-Dong; Zhang, Heng-Dong; Han, Lei; Shuai, Li-Guo; Ding, En-Min; Zhao, Qiu-Ni; Wang, Bo-Shen; Zhu, Bao-Li

    2016-03-01

    Circulating microRNAs (miRNAs) have attracted interests as non-invasive biomarkers of physiological and pathological conditions, which may be applied in noise-induced hearing loss (NIHL). However, no epidemiology studies have yet examined the potential effects of NIHL or noise exposure on miRNA expression profiles. We sought to identify permanent NIHL-related miRNAs and to predict the biological functions of the putative genes encoding the indicated miRNAs. In the discovery stage, we used a microarray assay to detect the miRNA expression profiles between pooled plasma samples from 10 noise-exposed individuals with normal hearing and 10 NIHL patients. In addition, we conducted a preliminary validation of six candidate miRNAs in the same 20 workers. Subsequently, three miRNAs were selected for expanded validation in 23 non-exposed individuals with normal hearing and 46 noise-exposed textile workers which including 23 noise-exposed workers with normal hearing and 23 NIHL patients. Moreover, we predicted the biological functions of the putative target genes using a Gene Ontology (GO) function enrichment analysis. In the discovery stage, compared with the noise exposures with normal hearing, 73 miRNAs demonstrated at least a 1.5-fold differential expression in the NIHL patients. In the preliminary validation, compared with the noise exposures, the plasma levels of miR-16-5p, miR-24-3p, miR-185-5p and miR-451a were all upregulated (P < 0.001) in the NIHL patients. In the expanded validation stage, compared with the non-exposures, the plasma levels of miR-24, miR-185-5p and miR-451a were all significantly downregulated (P < 0.001) in the exposures. And compared with the noise exposures, the plasma levels of miR-185-5p and miR-451a were slightly elevated (P < 0.001) in the NIHL patients, which were consistent with the results of preliminary validation and microarray analysis. The two indicated plasma miRNAs may be biomarkers of indicating responses to noise exposure

  10. Stimuli-Responsive Mesoporous Silica NPs as Non-viral Dual siRNA/Chemotherapy Carriers for Triple Negative Breast Cancer

    Directory of Open Access Journals (Sweden)

    Behrad Darvishi

    2017-06-01

    Full Text Available Triple negative breast cancer (TNBC is the most aggressive and lethal subtype of breast cancer. It is associated with a very poor prognosis and intrinsically resistant to several conventional and targeted chemotherapy agents and has a 5-year survival rate of less than 25%. Because the treatment options for TNBC are very limited and not efficient enough for achieving minimum desired goals, shifting toward a new generation of anti-cancer agents appears to be very critical. Among recent alternative approaches being proposed, small interfering RNA (siRNA gene therapy can potently suppress Bcl-2 proto-oncogene and p-glycoprotein gene expression, the most important chemotherapy resistance inducers in TNBC. When resensitized, primarily ineffective chemotherapy drugs turn back into valuable sources for further intensive chemotherapy. Regrettably, siRNA’s poor stability, rapid clearance in the circulatory system, and poor cellular uptake mostly hampers the beneficial outcomes of siRNA therapy. Considering these drawbacks, dual siRNA/chemotherapy drug encapsulation in targeted delivery vehicles, especially mesoporous silica nanoparticles (MSNs appears to be the most reasonable solution. The literature is full of reports of successful treatments of multi-drug-resistant cancer cells by administration of dual drug/siRNA-loaded MSNs. Here we tried to answer the question of whether application of a similar approach with identical delivery devices in TNBC is rational.

  11. Detection and quantification of serum or plasma HCV RNA: mini review of commercially available assays.

    Science.gov (United States)

    Le Guillou-Guillemette, Helene; Lunel-Fabiani, Francoise

    2009-01-01

    The treatment schedule (combination of compounds, doses, and duration) and the virological follow-up for management of antiviral treatment in patients chronically infected by HCV is now well standardized, but to ensure good monitoring of the treated patients, physicians need rapid, reproducible, and sensitive molecular virological tools with a wide range of detection and quantification of HCV RNA in blood samples. Several assays for detection and/or quantification of HCV RNA are currently commercially available. Here, all these assays are detailed, and a brief description of each step of the assay is provided. They are divided into two categories by method: those based on signal amplification and those based on target amplification. These two categories are then divided into qualitative, quantitative, and quantitative detection assays. The real-time reverse-transcription polymerase chain reaction (RT-PCR)-based assays are the most promising strategy in the HCV virological area.

  12. Interferon-β induced microRNA-129-5p down-regulates HPV-18 E6 and E7 viral gene expression by targeting SP1 in cervical cancer cells.

    Directory of Open Access Journals (Sweden)

    Jiarong Zhang

    Full Text Available Infection by human papillomavirus (HPV can cause cervical intraepithelial neoplasia (CIN and cancer. Down-regulation of E6 and E7 expression may be responsible for the positive clinical outcomes observed with IFN treatment, but the molecular basis has not been well determined. As miRNAs play an important role in HPV induced cervical carcinogenesis, we hypothesize that IFN-β can regulate the expressions of specific miRNAs in cervical cancer cells, and that these miRNAs can mediate E6 and E7 expression, thus modulate their oncogenic potential. In this study, we found that miR-129-5p to be a candidate IFN-β inducible miRNA. MiR-129-5p levels gradually decrease with the development of cervical intraepithelial lesions. Manipulation of miR-129-5p expression in Hela cells modulates HPV-18 E6 and E7 viral gene expression. Exogenous miR-129-5p inhibits cell proliferation in Hela cells, promotes apoptosis and blocks cell cycle progression in Hela cells. SP1 is a direct target of miR-129-5p in Hela cells. This study is the first report of a cellular miRNA with anti-HPV activity and provides new insights into regulatory mechanisms between the HPV and the IFN system in host cells at the miRNA level.

  13. Increased cellular immune responses and CD4+ T-cell proliferation correlate with reduced plasma viral load in SIV challenged recombinant simian varicella virus - simian immunodeficiency virus (rSVV-SIV vaccinated rhesus macaques

    Directory of Open Access Journals (Sweden)

    Pahar Bapi

    2012-08-01

    Full Text Available Abstract Background An effective AIDS vaccine remains one of the highest priorities in HIV-research. Our recent study showed that vaccination of rhesus macaques with recombinant simian varicella virus (rSVV vector – simian immunodeficiency virus (SIV envelope and gag genes, induced neutralizing antibodies and cellular immune responses to SIV and also significantly reduced plasma viral loads following intravenous pathogenic challenge with SIVMAC251/CX1. Findings The purpose of this study was to define cellular immunological correlates of protection in rSVV-SIV vaccinated and SIV challenged animals. Immunofluorescent staining and multifunctional assessment of SIV-specific T-cell responses were evaluated in both Experimental and Control vaccinated animal groups. Significant increases in the proliferating CD4+ T-cell population and polyfunctional T-cell responses were observed in all Experimental-vaccinated animals compared with the Control-vaccinated animals. Conclusions Increased CD4+ T-cell proliferation was significantly and inversely correlated with plasma viral load. Increased SIV-specific polyfunctional cytokine responses and increased proliferation of CD4+ T-cell may be crucial to control plasma viral loads in vaccinated and SIVMAC251/CX1 challenged macaques.

  14. Core Gene Expression and Association of Genotypes with Viral ...

    African Journals Online (AJOL)

    Purpose: To determine genotypic distribution, ribonucleic acid (RNA) RNA viral load and express core gene from Hepatitis C Virus (HCV) infected patients in Punjab, Pakistan. Methods: A total of 1690 HCV RNA positive patients were included in the study. HCV genotyping was tested by type-specific genotyping assay, viral ...

  15. Cerebrospinal fluid HIV-1 RNA levels in asymptomatic patients with early stage chronic HIV-1 infection: support for the hypothesis of local virus replication.

    Science.gov (United States)

    García, F; Niebla, G; Romeu, J; Vidal, C; Plana, M; Ortega, M; Ruiz, L; Gallart, T; Clotet, B; Miró, J M; Pumarola, T; Gatell, J M

    1999-08-20

    To assess HIV-1 RNA levels in cerebrospinal fluid (CSF) and their potential correlation with plasma viral load and central nervous system (CNS) HIV-1 infection markers in stable asymptomatic patients with a CD4 T cell count >500x10(6) cells/l. Consecutive patients screened for two trials were eligible for lumbar puncture assessment. At day 0, simultaneous samples of CSF and plasma were obtained and levels of total proteins, albumin, IgG, antibodies against HIV-1 p24 antigen, HIV-1 RNA (using the polymerase chain technique) and white cells were measured. The integrity of the blood-brain barrier was preserved (albumin index > or =7) in 59 out of 70 patients (84%). Intrathecal production of antibodies against HIV-1 p24 antigen was demonstrated in 55 out of 70 individuals (78%). Viral load in CSF was significantly lower than plasma values (3.13+/-0.95 versus 4.53+/-0.53, P = 0.0001). HIV-1 RNA was not detected in CSF in only three of the 70 patients (4%). Overall, there was a significant correlation between plasma and CSF HIV-1 RNA levels (r = 0.43, P = 0.0001); however, in 29 patients (41%) there were significant differences (>1.5 log10 copies/ml) between the viral loads in plasma and CSF. In the multivariate analysis, a high level of protein and white cells in CSF, but not the HIV-1 RNA plasma level, were factors independently associated with a higher level of HIV-1 RNA in CSF (P = 0.0001). HIV-1 RNA can be detected almost always in CSF of asymptomatic patients in early stages of HIV-1 infection including those with a preserved integrity of the blood-brain barrier. The important discrepancies between plasma and CSF viral load, and the independent association between CSF abnormalities and CSF viral load, support the hypothesis of local production of HIV-1.

  16. The Prognostic Value of Plasma Epstein-Barr Viral DNA and Tumor Response to Neoadjuvant Chemotherapy in Advanced-Stage Nasopharyngeal Carcinoma

    International Nuclear Information System (INIS)

    Liu, Li-Ting; Tang, Lin-Quan; Chen, Qiu-Yan; Zhang, Lu; Guo, Shan-Shan; Guo, Ling; Mo, Hao-Yuan; Zhao, Chong; Guo, Xiang; Cao, Ka-Jia; Qian, Chao-Nan; Zeng, Mu-Sheng; Bei, Jin-Xin; Hong, Ming-Huang; Shao, Jian-Yong; Sun, Ying; Ma, Jun; Mai, Hai-Qiang

    2015-01-01

    Purpose: To explore the prognostic value of the plasma load of Epstein-Barr viral (EBV) DNA and the tumor response to neoadjuvant chemotherapy (NACT) in advanced-stage nasopharyngeal carcinoma (NPC). Patients and Methods: In all, 185 consecutive patients with stage III to IVb NPC treated with NACT followed by concurrent chemoradiation therapy (CCRT) were prospectively enrolled. The primary endpoint was progression-free survival (PFS), and the secondary endpoints included locoregional relapse–free survival (LRFS) and distant metastasis–free survival (DMFS). Results: EBV DNA was detected in 165 (89%) patients before treatment but was undetectable in 127 (69%) patients after NACT. Detectable EBV DNA levels after NACT were correlated with poor prognosis (3-year PFS 71.8% vs 85.2%, P=.008 and 3-year DMFS 82.5% vs 92.3%, P=.013). An unsatisfactory tumor response (stable disease or disease progression) after NACT was also correlated with poor clinical outcome (3-year PFS 71.1% vs 85.9%, P=.005 and 3-year LRFS 82.7% vs 93.5%, P=.012). Multivariate analysis showed that the EBV DNA level after NACT (hazard ratio [HR] 2.31, 95% CI 1.18-4.54, P=.015) and the tumor response to NACT (HR 2.84, 95% CI 1.42-5.67, P=.003) were both significant prognostic factors for PFS. Multivariate analysis also showed that EBV DNA after NACT was the only significant predictor of DMFS (HR 2.99, 95% CI 1.25-7.15, P=.014) and that tumor response to NACT was the only significant predictor of LRFS (HR 3.31, 95% CI 1.21-9.07, P=.020). Conclusion: Detectable EBV DNA levels and an unsatisfactory tumor response (stable disease or disease progression) after NACT serve as predictors of poor prognosis for patients with advanced-stage NPC. These findings will facilitate further risk stratification, early treatment modification, or both before CCRT.

  17. The Prognostic Value of Plasma Epstein-Barr Viral DNA and Tumor Response to Neoadjuvant Chemotherapy in Advanced-Stage Nasopharyngeal Carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Li-Ting; Tang, Lin-Quan; Chen, Qiu-Yan; Zhang, Lu; Guo, Shan-Shan; Guo, Ling; Mo, Hao-Yuan; Zhao, Chong; Guo, Xiang; Cao, Ka-Jia; Qian, Chao-Nan [Sun Yat-sen University Cancer Center, State Key Laboratory of Oncology in South China (China); Collaborative Innovation Center for Cancer Medicine, Guangzhou (China); Department of Nasopharyngeal Carcinoma, Sun Yat-sen University Cancer Center, Guangzhou (China); Zeng, Mu-Sheng; Bei, Jin-Xin [Sun Yat-sen University Cancer Center, State Key Laboratory of Oncology in South China (China); Collaborative Innovation Center for Cancer Medicine, Guangzhou (China); Hong, Ming-Huang [Sun Yat-sen University Cancer Center, State Key Laboratory of Oncology in South China (China); Collaborative Innovation Center for Cancer Medicine, Guangzhou (China); Good Clinical Practice Center, Sun Yat-sen University Cancer Center, Guangzhou (China); Shao, Jian-Yong [Sun Yat-sen University Cancer Center, State Key Laboratory of Oncology in South China (China); Collaborative Innovation Center for Cancer Medicine, Guangzhou (China); Department of Molecular Diagnostics, Sun Yat-sen University Cancer Center, Guangzhou (China); Sun, Ying; Ma, Jun [Sun Yat-sen University Cancer Center, State Key Laboratory of Oncology in South China (China); Collaborative Innovation Center for Cancer Medicine, Guangzhou (China); Department of Radiation Oncology, Sun Yat-sen University Cancer Center, Guangzhou (China); Mai, Hai-Qiang, E-mail: maihq@sysucc.org.cn [Sun Yat-sen University Cancer Center, State Key Laboratory of Oncology in South China (China); Collaborative Innovation Center for Cancer Medicine, Guangzhou (China); Department of Nasopharyngeal Carcinoma, Sun Yat-sen University Cancer Center, Guangzhou (China)

    2015-11-15

    Purpose: To explore the prognostic value of the plasma load of Epstein-Barr viral (EBV) DNA and the tumor response to neoadjuvant chemotherapy (NACT) in advanced-stage nasopharyngeal carcinoma (NPC). Patients and Methods: In all, 185 consecutive patients with stage III to IVb NPC treated with NACT followed by concurrent chemoradiation therapy (CCRT) were prospectively enrolled. The primary endpoint was progression-free survival (PFS), and the secondary endpoints included locoregional relapse–free survival (LRFS) and distant metastasis–free survival (DMFS). Results: EBV DNA was detected in 165 (89%) patients before treatment but was undetectable in 127 (69%) patients after NACT. Detectable EBV DNA levels after NACT were correlated with poor prognosis (3-year PFS 71.8% vs 85.2%, P=.008 and 3-year DMFS 82.5% vs 92.3%, P=.013). An unsatisfactory tumor response (stable disease or disease progression) after NACT was also correlated with poor clinical outcome (3-year PFS 71.1% vs 85.9%, P=.005 and 3-year LRFS 82.7% vs 93.5%, P=.012). Multivariate analysis showed that the EBV DNA level after NACT (hazard ratio [HR] 2.31, 95% CI 1.18-4.54, P=.015) and the tumor response to NACT (HR 2.84, 95% CI 1.42-5.67, P=.003) were both significant prognostic factors for PFS. Multivariate analysis also showed that EBV DNA after NACT was the only significant predictor of DMFS (HR 2.99, 95% CI 1.25-7.15, P=.014) and that tumor response to NACT was the only significant predictor of LRFS (HR 3.31, 95% CI 1.21-9.07, P=.020). Conclusion: Detectable EBV DNA levels and an unsatisfactory tumor response (stable disease or disease progression) after NACT serve as predictors of poor prognosis for patients with advanced-stage NPC. These findings will facilitate further risk stratification, early treatment modification, or both before CCRT.

  18. Occult HCV Infection (OCI) Diagnosis in Cirrhotic and Non-cirrhotic Naïve Patients by Intra-PBMC Nested Viral RNA PCR.

    Science.gov (United States)

    Abd Alla, Mohamed Darwish Ahmed; Elibiary, Saleh Ahmed; Wu, George Y; El-Awady, Mostafa Kamel

    2017-12-28

    Background and Aims: Occult HCV infections (OCIs) include IgG antibody seronegative cryptogenic (COCIs), as well as seropositive secondary naïve (SNOCIs) and experienced (SEOCIs) cases. We used peripheral-blood-mononuclear-cell (PBMC)-PCR to evaluate COCIs and SNOCIs prevalence, serum HCV spontaneous disappearance (SCSD) in naïve cirrhotics and non-cirrhotics, intra-PBMC HCV-RNA strands in relation to cirrhosis density in naïve non-viremia cases, and HCV-RNA seroconversion after 1 year of solitary naïve intra-PBMC infection. Methods: The anti-HCV IgG antibody-positive naïve-patients ( n = 785) were classified into viremic ( n = 673) and non-viremic [ n = 112, including non-cirrhotics ( n = 55) and cirrhotics ( n = 57)], and 62 controls without evidence of HCV-infection. Controls and post-HCV non-viremia cases ( n = 62+112 = 174) were submitted to hepatic Fibroscan-Elastography evaluation. All subjects ( n = 847) were screened for intra-PBMC HCV-RNA sense and antisense strands by nested-PCR. Results: Naïve-OCI cases (4.84%) that were diagnosed by PBMC-PCR significantly raised the total numbers of HCV-infection to 714 ( p = 0.01). The percent positivity of SNOCIs (34.82%) was significantly higher than for asymptomatic-COCIs (3.125%, p = 0.0001). Comparing PBMC-PCR with single-step-reverse-transcription (SRT)-PCR for identification of SCSD in naïve IgG antibody-positive non-viremia patients ( n = 112) revealed a decline in SCSD prevalence by PBMC-PCR (from 14.27% to 9.3%), regardless of presence of hepatic cirrhosis ( p = 0.03). SCSD was found to be higher by PBMC-PCR in non-cirrhotics compared to cirrhotics ( p = 0.0001), with an insignificant difference when using SRT-PCR ( p = 0.45). Intra-PBMC HCV-RNA infection was significantly more frequent in cirrhotics compared to both non-cirrhotics and controls ( p < 0.0005). An increased hepatic fibrosis density was recognized in intra-PBMC HCV-RNA infection with sense ( p = 0.0001) or antisense strand ( p = 0

  19. Frequency of hepatitis C viral RNA in anti-hepatitis C virus non-reactive blood donors with normal alanine aminotransferase

    International Nuclear Information System (INIS)

    Ali, N.; Moinuddin, A.; Ahmed, S.A.

    2010-01-01

    To determine the frequency of HCV RNA in an anti-HCV non-reactive blood donor population with normal ALT, and its cost effectiveness. Study Design: An observational study. Place and Duration of Study: Baqai Institute of Haematology, Baqai Medical University, Karachi, and Combined Military Hospital, Malir Cantt, Karachi, from May 2006 to April 2008. Methodology: After initial interview and mini-medical examination, demographic data of blood donors was recorded, and anti-HCV, HBsAg and HIV were screened by third generation ELISA. Those reactive to anti-HCV, HbsAg and/or HIV were excluded. Four hundred consecutive donors with ALT within the reference range of 15-41 units/L were included in study. HCV RNA RT-PCR was performed on 5 sample mini-pools using Bio-Rad Real time PCR equipment. Results: All 400 donors were male, with mean age 27 years SD + 6.2. ALT of blood donors varied between 15-41 U/L with mean of 31.5+6.4 U/L, HCV RNA was detected in 2/400 (0.5%) blood donors. Screening one blood bag for HCV RNA costs Rs 4,000.00 equivalent to 50 US dollars, while screening through 5 sample mini-pools was Rs. 800.00 equivalent to approximately 10 US dollars. Conclusion: HCV RNA frequency was 0.5% (2/400) in the studied anti-HCV non-reactive normal ALT blood donors. Screening through mini-pools is more cost-effective. (author)

  20. An oligonucleotide complementary to the SL-B1 domain in the 3'-end of the minus-strand RNA of the hepatitis C virus inhibits in vitro initiation of RNA synthesis by the viral polymerase

    International Nuclear Information System (INIS)

    Reigadas, Sandrine; Ventura, Michel; Andreola, Marie-Line; Michel, Justine; Gryaznov, Sergei; Tarrago-Litvak, Laura; Litvak, Simon; Astier-Gin, Therese

    2003-01-01

    We describe oligonucleotides (ODNs) that inhibit hepatitis C virus (HCV) RNA synthesis in vitro. From a series of 13 ODNs complementary to the 3'-end of the minus-strand HCV RNA, only 4 inhibited RNA synthesis with IC 50 values lower than 1 μM. The inhibition was sequence-specific, since no effect was observed when the ODNs were used with a noncomplementary template. The introduction of a 2'-O-methyl modification increased the inhibitor activity 11-fold (IC 50 = 50 nM) in just 1 (ODN7) of the 4 inhibitory ODNs. ODNs did not inhibit RNA synthesis by interfering with the elongation process as no short RNAs products were detected. We also show that ODN7 did not prevent binding of NS5B to the template or cause polymerase trapping by the duplex RNA/ODN. Our data demonstrate that ODN7 inhibits the initiation process, most probably by modifying structural features present at the 3'-end of the minus-strand RNA

  1. Increased uncoupling protein-2 mRNA abundance and glucocorticoid action in adipose tissue in the sheep fetus during late gestation is dependent on plasma cortisol and triiodothyronine

    Science.gov (United States)

    Gnanalingham, MG; Mostyn, A; Forhead, AJ; Fowden, AL; Symonds, ME; Stephenson, T

    2005-01-01

    The endocrine regulation of uncoupling protein-2 (UCP2), an inner mitochondrial protein, in fetal adipose tissue remains unclear. The present study aimed to determine if fetal plasma cortisol and triiodothyronine (T3) influenced the mRNA abundance of UCP2, glucocorticoid receptor (GR) and 11β-hydroxysteroid dehydrogenase type 1 (11βHSD1) and 2 (11βHSD2) in fetal adipose tissue in the sheep during late gestation. Perirenal–abdominal adipose tissue was sampled from ovine fetuses to which either cortisol (2–3 mg kg−1 day−1) or saline was infused for 5 days up to 127–130 days gestation, or near term fetuses (i.e. 142–145 days gestation) that were either adrenalectomised (AX) or remained intact. Fetal plasma cortisol and T3 concentrations were higher in the cortisol infused animals and lower in AX fetuses compared with their corresponding control group, and increased with gestational age. UCP2 and GR mRNA abundance were significantly lower in AX fetuses compared with age-matched controls, and increased with gestational age and by cortisol infusion. Glucocorticoid action in fetal adipose tissue was augmented by AX and suppressed by cortisol infusion, the latter also preventing the gestational increase in 11βHSD1 mRNA and decrease in 11βHSD2 mRNA. When all treatment groups were combined, both fetal plasma cortisol and T3 concentrations were positively correlated with UCP2, GR and 11βHSD2 mRNA abundance, but negatively correlated with 11βHSD1 mRNA abundance. In conclusion, plasma cortisol and T3 are both required for the late gestation rise in UCP2 mRNA and differentially regulate glucocorticoid action in fetal adipose tissue in the sheep during late gestation. PMID:15961419

  2. Maternal plasma levels of cell-free β-HCG mRNA as a prenatal diagnostic indicator of placenta accrete.

    Science.gov (United States)

    Zhou, J; Li, J; Yan, P; Ye, Y H; Peng, W; Wang, S; Wang, X Tong

    2014-09-01

    Several biomarkers, including maternal serum creatinine kinase and α-fetoprotein, have been described as potential tools for the diagnosis of placental abnormalities. This study aimed to determine whether maternal plasma mRNA levels of the β subunit of human chorionic gonadotropin (β-HCG) could predict placenta accreta prenatally. Sixty-eight singleton pregnant women with prior cesarean deliveries (CDs) were classified into three groups: normal placentation (35 women, control group); placenta previa alone (21 women, placenta previa group); and both placenta previa and placenta accreta (12 women, placenta previa/accreta group). Maternal plasma concentrations of cell-free β-HCG mRNA were measured by real-time reverse-transcription polymerase chain reaction and were expressed as multiples of the median (MoM). Cell-free β-HCG mRNA concentrations (MoM, range) were significantly higher in women with placenta accreta (3.65, 2.78-7.19) than in women with placenta previa (0.94, 0.00-2.97) or normal placentation (1.00, 0.00-2.69) (Steel-Dwass test, P accreta group, the concentration of cell-free β-HCG mRNA was significantly higher among women who underwent CDs with hysterectomy (4.41, 3.49-7.19) than among women whose CDs did not result in hysterectomy (3.20, 2.78-3.70) (Mann-Whitney U test, P = 0.012). An increased level of cell-free β-HCG mRNA in the maternal plasma of women with placenta accreta may arise from direct uteroplacental transfer of cell-free placental mRNA molecules. The concentration of cell-free β-HCG mRNA in maternal plasma may be applicable to the prenatal diagnosis of placenta accreta, especially to identify women with placenta accreta likely to require hysterectomy. Copyright © 2014 Elsevier Ltd. All rights reserved.

  3. Circulating microRNA (miRNA Expression Profiling in Plasma of Patients with Gestational Diabetes Mellitus Reveals Upregulation of miRNA miR-330-3p

    Directory of Open Access Journals (Sweden)

    Guido Sebastiani

    2017-12-01

    Full Text Available Gestational diabetes mellitus (GDM is characterized by insulin resistance accompanied by low/absent beta-cell compensatory adaptation to the increased insulin demand. Although the molecular mechanisms and factors acting on beta-cell compensatory response during pregnancy have been partially elucidated and reported, those inducing an impaired beta-cell compensation and function, thus evolving in GDM, have yet to be fully addressed. MicroRNAs (miRNAs are a class of small endogenous non-coding RNAs, which negatively modulate gene expression through their sequence-specific binding to 3′UTR of mRNA target. They have been described as potent modulators of cell survival and proliferation and, furthermore, as orchestrating molecules of beta-cell compensatory response and function in diabetes. Moreover, it has been reported that miRNAs can be actively secreted by cells and found in many biological fluids (e.g., serum/plasma, thus representing both optimal candidate disease biomarkers and mediators of tissues crosstalk(s. Here, we analyzed the expression profiles of circulating miRNAs in plasma samples obtained from n = 21 GDM patients and from n = 10 non-diabetic control pregnant women (24–33 weeks of gestation using TaqMan array microfluidics cards followed by RT-real-time PCR single assay validation. The results highlighted the upregulation of miR-330-3p in plasma of GDM vs non-diabetics. Furthermore, the analysis of miR-330-3p expression levels revealed a bimodally distributed GDM patients group characterized by high or low circulating miR-330 expression and identified as GDM-miR-330high and GDM-miR-330low. Interestingly, GDM-miR-330high subgroup retained lower levels of insulinemia, inversely correlated to miR-330-3p expression levels, and a significant higher rate of primary cesarean sections. Finally, miR-330-3p target genes analysis revealed major modulators of beta-cell proliferation and of insulin secretion, such as the

  4. Valuable Virality

    NARCIS (Netherlands)

    Akpinar, E.; Berger, Jonah

    2017-01-01

    Given recent interest in social media, many brands now create content that they hope consumers will view and share with peers. While some campaigns indeed go “viral,” their value to the brand is limited if they do not boost brand evaluation or increase purchase. Consequently, a key question is how

  5. Distribution of HIV RNA in CSF and Blood is linked to CD4/CD8 Ratio During Acute HIV.

    Science.gov (United States)

    Chan, Phillip; Patel, Payal; Hellmuth, Joanna; Colby, Donn J; Kroon, Eugène; Sacdalan, Carlo; Pinyakorn, Suteeraporn; Jagodzinski, Linda; Krebs, Shelly; Ananworanich, Jintanat; Valcour, Victor; Spudich, Serena

    2018-05-07

    HIV RNA levels in the plasma and cerebrospinal fluid (CSF) are correlated in chronic HIV infection but their dynamics have not been characterized during acute infection. This study analyzed predictors of CSF HIV RNA and relative degree of CNS viral transmigration expressed as plasma minus CSF HIV log10 RNA (PCratio) during untreated acute HIV infection. CSF immune markers were compared between groups with different PCratio. 117 mostly male (97%) participants in the RV254 cohort in Bangkok, Thailand, had median age 28 years and an estimated median 18 days duration of infection; forty-three (37%) were Fiebig stages I/II. Twenty-seven (23%) had CSF HIV RNA CSF HIV RNA and PCratio of 3.76 and 2.36 Log10 copies/mL, respectively. HIV RNA peaked at Fiebig III in plasma and Fiebig IV in CSF. In multivariable analyses, plasma HIV RNA and CD4/CD8 ratio independently correlated with CSF HIV RNA (pCSF neopterin, sCD163, IL-6 and sCD14 levels (all pCSF HIV RNA and PCratio, suggesting that immune responses modulate CNS viral entry at early infection.

  6. Study on the plasma leptin level and leptin mRNA expression in cancerous breast tissue in patients with breast carcinoma complicated with obesity

    International Nuclear Information System (INIS)

    Li Chunrui; Liu Wenli; Sun Hanying; Zhou Jianfeng

    2006-01-01

    Objective: To study the plasma leptin level and leptin mRNA expression in cancerous breast tissue in patients with breast cancer complicated with obesity. Methods: Plasma leptin levels were measured with RIA in 48 breast cancer patients with obesity, 36 patients with various benign breast disorders and obesity and 40 controls (with simple obesity only). The leptin mRNA expression in the surgical specimens from the 84 patients with breast disease was also examined with RT-PCR, Results: The plasma leptin levels in the breast cancer patients (12.02 ± 1.23 μg/L) were significantly higher than those in patients with benign breast disorders (9.84 ± 0.98 μg/L) and controls (9.79 ± 1.16 μg/L) (both P<0.05). The expression levels of leptin mRNA in specimens from malignant breast disease (0.71 ± 0.32), were significantly higher than those in specimens from benign breast diseases (0.41 ± 0.26) (P<0.05), The plasma leptin levels and the tissue leptin mRNA expression levels were mutually positively correlated (r=0.4220 ,P 0.0180). These levels were not correlated with the presence of axillary metastasis, TMN stage, menstrual status, pathological classification and other parameters. Conclusion: Leptin might be a promotive factor in the development of breast cancer. (authors)

  7. Dynamics of 103K/N and 184M/V HIV-1 drug resistant populations: relative comparison in plasma virus RNA versus CD45RO+T cell proviral DNA

    DEFF Research Database (Denmark)

    Jakobsen, Martin Roelsgaard; Tolstrup, M; Bertelsen, L

    2007-01-01

    on real-time PCR and amplification refractory mutation system (ARMS). RESULTS: The 103N and 184V mutations were not detected in patients with stable low viremia. Patients previously exposed to mono or dual therapy often carried minor viral populations of either one or both mutations in plasma. The viral......BACKGROUND: Viral populations defined by 103K/N and 184M/V as linked or single mutations in the HIV-1 reverse transcriptase gene were investigated in plasma samples and compared with previous findings in the CD45RO(+)T cell compartment. OBJECTIVE: To develop an ARMS assay for plasma virions...... an unequal distribution of linked-mutation populations in plasma and CD45RO(+)T cells. Furthermore, the linked 103N-184V mutation may be more fit than the single 184V mutation and this linked population emerges rapidly under inadequate drug pressure. Udgivelsesdato: 2007-Jul...

  8. Relationship between hunger, adherence to antiretroviral therapy and plasma HIV RNA suppression among HIV-positive illicit drug users in a Canadian setting.

    Science.gov (United States)

    Anema, Aranka; Kerr, Thomas; Milloy, M-J; Feng, Cindy; Montaner, Julio S G; Wood, Evan

    2014-04-01

    Food insecurity may be a barrier to achieving optimal HIV treatment-related outcomes among illicit drug users. This study therefore, aimed to assess the impact of severe food insecurity, or hunger, on plasma HIV RNA suppression among illicit drug users receiving antiretroviral therapy (ART). A cross-sectional Multivariate logistic regression model was used to assess the potential relationship between hunger and plasma HIV RNA suppression. A sample of n = 406 adults was derived from a community-recruited open prospective cohort of HIV-positive illicit drug users, in Vancouver, British Columbia (BC), Canada. A total of 235 (63.7%) reported "being hungry and unable to afford enough food," and 241 (59.4%) had plasma HIV RNA hunger was associated with lower odds of plasma HIV RNA suppression (Odds Ratio = 0.59, 95% confidence interval [CI]: 0.39-0.90, p = 0.015). In multivariate analyses, this association was no longer significant after controlling for socio-demographic, behavioral, and clinical characteristics, including 95% adherence (Adjusted Odds Ratio [AOR] = 0.65, 95% CI: 0.37-1.10, p = 0.105). Multivariate models stratified by 95% adherence found that the direction and magnitude of this association was not significantly altered by the adherence level. Hunger was common among illicit drug users in this setting. Although, there was an association between hunger and lower likelihood of plasma HIV RNA suppression, this did not persist in adjusted analyses. Further research is warranted to understand the social-structural, policy, and physical factors shaping the HIV outcomes of illicit drug users.

  9. Detection of HIV-RNA-positive monocytes in peripheral blood of HIV-positive patients by simultaneous flow cytometric analysis of intracellular HIV RNA and cellular immunophenotype.

    Science.gov (United States)

    Patterson, B K; Mosiman, V L; Cantarero, L; Furtado, M; Bhattacharya, M; Goolsby, C

    1998-04-01

    Determinations of plasma HIV viral RNA copy numbers help to define the kinetics of HIV-1 infection in vivo and to monitor antiretroviral therapy. However, questions remain regarding the identity of various infected cell types contributing to this free virus pool and to the in vivo lifecycle of HIV during disease progression. Characterization of a novel fluorescence in situ hybridization (FISH) assay employing a pool of labeled oligonucleotide probes directed against HIV RNA was done followed by coupling of the FISH assay with simultaneous surface immunophenotyping to address these questions. In vitro characterizations of this assay using tumor necrosis factor-alpha stimulated and unstimulated ACH-2 cells demonstrated the ability to detect < 5% HIV RNA positive cells with a sensitivity of < 30 RNA copies per cell. Peripheral blood mononuclear cells from 39 HIV-seropositive patients on no, single, combination, or triple drug therapy and 8 HIV-seronegative patients were examined. The majority of HIV-positive patients (24/39) harbored monocytes positive for HIV RNA and a significantly higher fraction of patients with high plasma viral load carried positive monocytes (13/16) than did patients in the low plasma viral load group (11/23). These results demonstrate the effectiveness of a novel FISH assay for identifying and monitoring HIV-infected cell populations in the peripheral blood of HIV-positive patients. In addition, monocytes are a major source of cellular HIV virus in the peripheral blood of HIV patients, even with progression of disease.

  10. RNA/PNA Approach

    Indian Academy of Sciences (India)

    In this approach we want to develop structural analogue of the leader that might have higher affinity towards the Phosphoprotein, but would impair the dimerization process and viral leader RNA binding.

  11. Infectious dengue vesicles derived from CD61+ cells in acute patient plasma exhibited a diaphanous appearance

    Science.gov (United States)

    Hsu, Alan Yi-Hui; Wu, Shang-Rung; Tsai, Jih-Jin; Chen, Po-Lin; Chen, Ya-Ping; Chen, Tsai-Yun; Lo, Yu-Chih; Ho, Tzu-Chuan; Lee, Meed; Chen, Min-Ting; Chiu, Yen-Chi; Perng, Guey Chuen

    2015-01-01

    The levels of neutralizing antibody to a pathogen are an effective indicator to predict efficacy of a vaccine in trial. And yet not all the trial vaccines are in line with the theory. Using dengue virus (DENV) to investigate the viral morphology affecting the predictive value, we evaluated the viral morphology in acute dengue plasma compared to that of Vero cells derived DENV. The virions in plasma were infectious and heterogeneous in shape with a “sunny-side up egg” appearance, viral RNA was enclosed with CD61+ cell-derived membrane interspersed by the viral envelope protein, defined as dengue vesicles. The unique viral features were also observed from ex vivo infected human bone marrow. Dengue vesicles were less efficiently neutralized by convalescent patient serum, compared to virions produced from Vero cells. Our results exhibit a reason why potencies of protective immunity fail in vivo and significantly impact dengue vaccine and drug development. PMID:26657027

  12. Structural equation modelling of viral tropism reveals its impact on achieving viral suppression within 6 months in treatment-naive HIV-1-infected patients after combination antiretroviral therapy.

    Science.gov (United States)

    Mengoli, Carlo; Andreis, Samantha; Scaggiante, Renzo; Cruciani, Mario; Bosco, Oliviero; Ferretto, Roberto; Leoni, Davide; Maffongelli, Gaetano; Basso, Monica; Torti, Carlo; Sarmati, Loredana; Andreoni, Massimo; Palù, Giorgio; Parisi, Saverio Giuseppe

    2017-01-01

    To evaluate the role of pre-treatment co-receptor tropism of plasma HIV on the achievement of viral suppression (plasma HIV RNA 1.69 log 10 copies/mL) at the sixth month of combination antiretroviral therapy (cART) in a cohort of naive patients using, for the first time in this context, a path analysis (PA) approach. Adult patients with chronic infection by subtype B HIV-1 were consecutively enrolled from the start of first-line cART (T0). Genotypic analysis of viral tropism was performed on plasma and interpreted using the bioinformatic tool Geno2pheno, with a false positive rate of 10%. A Bayesian network starting from the viro-immunological data at T0 and at the sixth month of treatment (T1) was set up and this model was evaluated using a PA approach. A total of 262 patients (22.1% bearing an X4 virus) were included; 178 subjects (67.9%) achieved viral suppression. A significant positive indirect effect of bearing X4 virus in plasma at T0 on log 10 HIV RNA at T1 was detected (P = 0.009), the magnitude of this effect was, however, over 10-fold lower than the direct effect of log 10 HIV RNA at T0 on log 10 HIV RNA at T1 (P = 0.000). Moreover, a significant positive indirect effect of bearing an X4 virus on log 10 HIV RNA at T0 (P = 0.003) was apparent. PA overcame the limitations implicit in common multiple regression analysis and showed the possible role of pre-treatment viral tropism at the recommended threshold on the outcome of plasma viraemia in naive patients after 6 months of therapy. © The Author 2016. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  13. The Transcription Factor T-Bet Is Regulated by MicroRNA-155 in Murine Anti-Viral CD8+ T Cells via SHIP-1

    Directory of Open Access Journals (Sweden)

    Jennifer L. Hope

    2017-12-01

    Full Text Available We report here that the expression of the transcription factor T-bet, which is known to be required for effector cytotoxic CD8+ T lymphocytes (CTL generation and effector memory cell formation, is regulated in CTL by microRNA-155 (miR-155. Importantly, we show that the proliferative effect of miR-155 on CD8+ T cells is mediated by T-bet. T-bet levels in CTL were controlled in vivo by miR-155 via SH2 (Src homology 2-containing inositol phosphatase-1 (SHIP-1, a known direct target of miR-155, and SHIP-1 directly downregulated T-bet. Our studies reveal an important and unexpected signaling axis between miR-155, T-bet, and SHIP-1 in in vivo CTL responses and suggest an important signaling module that regulates effector CTL immunity.

  14. Impact of Chloroquine on Viral Load in Breast Milk

    Science.gov (United States)

    Semrau, Katherine; Kuhn, Louise; Kasonde, Prisca; Sinkala, Moses; Kankasa, Chipepo; Shutes, Erin; Vwalika, Cheswa; Ghosh, Mrinal; Aldrovandi, Grace; Thea, Donald M.

    2006-01-01

    Summary The anti-malarial agent chloroquine has activity against HIV. We compared the effect of chloroquine (n = 18) to an anti-malarial agent without known anti-HIV-activity, sulfadoxine-pyrimethamine (n = 12), on breast milk HIV RNA levels among HIV-infected breastfeeding women in Zambia. After adjusting for CD4 count and plasma viral load, chloroquine was associated with a trend towards lower levels of HIV RNA in breast milk compared with sulfadoxine-pyrimethamine (P 0.05). Higher breastmilk viral load was also observed among women receiving presumptive treatment = for symptomatic malaria compared with asymptomatic controls and among controls reporting fever in the prior week. Further research is needed to determine the potential role of chloroquine in prevention of HIV transmission through breastfeeding. Impacte de la chloroquine sur la charge virale dans le lait maternelle La chloroquine, agent antimalarique, a une activité contre le VIH. Nous avons comparé l’effet de la chloroquine à celui d’un autre agent antimalarique, la sulfadoxine-pyrimethamine, dont l’activité sur le VIH n’est pas connue, en mesurant les taux d’ARN de VIH dans le lait maternel de femmes allaitantes infectées par le VIH en Zambie. Après ajustement pour les taux de CD4 et la charge virale dans le plasma, la chloroquine comparée à la sulfadoxine pyrimethamine était associée à une tendance vers des teneurs plus bas en ARN de VIH dans le lait maternel (P = 0,05). Des charges virales plus élevées dans le lait maternel étaient aussi observées chez des femmes recevant un traitement présomptif pour des symptômes de malaria par rapport aux contrôles asymptomatiques et par rapport à des contrôles rapportant de la fièvre durant la première semaine. Des études supplémentaires sont nécessaires pour déterminer le rôle potentiel de la chloroquine dans la prévention de la transmission du VIH par l’allaitement maternel. mots clésVIH, malaria, allaitement maternel

  15. Persistent CSF but not Plasma HIV RNA, is Associated with Increased Risk of New-onset Moderate-to-Severe Depressive Symptoms; A Prospective Cohort Study

    Science.gov (United States)

    Hammond, Edward R.; Crum, Rosa M.; Treisman, Glenn J.; Mehta, Shruti H.; Clifford, David B.; Ellis, Ronald J.; Gelman, Benjamin B.; Grant, Igor; Letendre, Scott L.; Marra, Christina M; Morgello, Susan; Simpson, David M.; McArthur, Justin C.

    2016-01-01

    Major depressive disorder is the most common neuropsychiatric complication in human immunodeficiency virus (HIV) infections and is associated with worse clinical outcomes. We determined if detectable cerebrospinal fluid (CSF) HIV ribonucleic acid (RNA) at threshold ≥50 copies/ml is associated with increased risk of depression. The CNS HIV Anti-Retroviral Therapy Effects Research (CHARTER) cohort is a six-center US-based prospective cohort with bi-annual follow-up 674 participants. We fit linear mixed models (N=233) and discrete-time survival models (N=154; 832 observations), to evaluate trajectories of Beck Depression Inventory (BDI) II scores, and the incidence of new-onset moderate-to-severe depressive symptoms (BDI≥17) among participants, on combination antiretroviral therapy (cART), who were free of depression at study entry, and received a minimum of three CSF examinations over 2,496 person-months follow-up. Detectable CSF HIV RNA (threshold ≥50 copies/ml) at any visit was associated with a 4.7-fold increase in new-onset depression at subsequent visits adjusted for plasma HIV RNA and treatment adherence; hazard ratio (HR)=4.76, (95% CI: 1.58–14.3); P=0.006. Depression (BDI) scores were 2.53 points higher (95% CI: 0.47–4.60; P=0.02) over 6 months if CSF HIV RNA was detectable at a prior study visit in fully adjusted models including age, sex, race, education, plasma HIV RNA, duration and adherence of cART, and lifetime depression diagnosis by DSM-IV criteria. Persistent CSF but not plasma HIV RNA, is associated with an increased risk for new-onset depression. Further research evaluating the role of immune activation and inflammatory markers may improve our understanding of this association. PMID:26727907

  16. Evaluation of the performance of Abbott m2000 and Roche COBAS Ampliprep/COBAS Taqman assays for HIV-1 viral load determination using dried blood spots and dried plasma spots in Kenya.

    Science.gov (United States)

    Zeh, Clement; Ndiege, Kenneth; Inzaule, Seth; Achieng, Rebecca; Williamson, John; Chih-Wei Chang, Joy; Ellenberger, Dennis; Nkengasong, John

    2017-01-01

    Routine HIV viral load testing is not widely accessible in most resource-limited settings, including Kenya. To increase access to viral load testing, alternative sample types like dried blood spots (DBS), which overcome the logistic barriers associated with plasma separation and cold chain shipment need to be considered and evaluated. The current study evaluated matched dried blood spots (DBS) and dried plasma spots (DPS) against plasma using the Abbott M 2000 (Abbott) and Roche Cobas Ampliprep/Cobas TaqMan (CAP/CTM) quantitative viral load assays in western Kenya. Matched plasma DBS and DPS were obtained from 200 HIV-1 infected antiretroviral treatment (ART)-experienced patients attending patient support centers in Western Kenya. Standard quantitative assay performance parameters with accompanying 95% confidence intervals (CI) were assessed at the assays lower detection limit (400cps/ml for CAP/CTM and 550cps/ml for Abbott) using SAS version 9.2. Receiver operating curves (ROC) were further used to assess viral-load thresholds with best assay performance (reference assay CAP/CTM plasma). Using the Abbott test, the sensitivity and specificity, respectively, for DPS were (97.3%, [95%CI: 93.2-99.2] and 98.1% [95%CI: 89.7-100]) and those for DBS (93.9% [95%CI: 88.8-97.2] and 88.0% [95%CI: 82.2-92.4]). The correlation and agreement using paired plasma and DPS/DBS were strong, with r2 = 90.5 and rc = 68.1. The Bland-Altman relative percent change was 95.3 for DPS, (95%CI: 90.4-97.7) and 73.6 (95%CI: 51.6-86.5) for DBS. Using the CAP/CTM assay, the sensitivity for DBS was significantly higher compared to DPS (100.0% [95% CI: 97.6-100.0] vs. 94.7% [95%CI: 89.8-97.7]), while the specificity for DBS was lower: 4%, [95% CI: 0.4-13.7] compared to DPS: 94.0%, [95% CI: 83.5-98.7]. When compared under different clinical relevant thresholds, the accuracy for the Abbott assay was 95% at the 1000cps/ml cut-off with a sensitivity and specificity of 96.6% [95% CI 91.8-98.7] and 90

  17. Plasma LncRNA-ATB, a Potential Biomarker for Diagnosis of Patients with Coal Workers’ Pneumoconiosis: A Case-Control Study

    Directory of Open Access Journals (Sweden)

    Jixuan Ma

    2016-08-01

    Full Text Available LncRNA-ATB (lncRNA was activated by transforming growth factor-β has been reported to be involved in specific physiological and pathological processes in human diseases, and could serve as biomarkers for cancers. However, the role of lncRNA-ATB in coal workers’ pneumoconiosis (CWP is still unknown. This study aimed to investigate the association between lncRNA-ATB and CWP. Quantitative real-time polymerase chain reaction was performed to detect plasma lncRNA-ATB expression in 137 CWP patients, 72 healthy coal miners and 168 healthy controls. LncRNA-ATB was significantly upregulated in CWP (p < 0.05. Compared with the healthy controls and healthy coal miners, the odds ratios (ORs (95% confidence interval (CI for CWP were 2.57 (1.52–4.33 and 2.17 (1.04–4.53, respectively. LncRNA-ATB was positively associated with transforming growth factor-β1 (TGF-β1 (r = 0.30, p = 0.003 and negative correlated with vital capacity (VC (r = −0.18, p = 0.033 and forced vital capacity (FVC (r = −0.18, p = 0.046 in CWP patients. Compared with healthy controls, the area under the curve (AUC was 0.84, resulting in a 71.17% sensitivity and 88.14% specificity. When compared with healthy coal miners, the AUC was 0.83, the sensitivity and specificity were 70.07% and 86.36%, respectively. LncRNA-ATB expression is commonly increased in CWP and significantly correlates with the TGF-β1 in CWP patients. Furthermore, elevated lncRNA-ATB was associated with CWP risk and may serve as a potential biomarker for CWP.

  18. Comparison between Roche and Xpert in HIV-1 RNA quantitation: A high concordance between the two techniques except for a CRF02_AG subtype variant with high viral load titters detected by Roche but undetected by Xpert.

    Science.gov (United States)

    Avidor, Boaz; Matus, Natalia; Girshengorn, Shirley; Achsanov, Svetlana; Gielman, Simona; Zeldis, Irene; Schweitzer, Inbal; Adler, Amos; Turner, Dan

    2017-08-01

    HIV-1 viral load (VL) testing is important to predict viral progression and to monitor the response to antiretroviral therapy. New HIV-1 VL tests are continuously introduced to the market. Their performance is usually compared to Abbott and/or Roche HIV-1 VL assays, as reference. The Xpert HIV-1 VL test was recently introduced, but its performance compared to Roche has not been sufficiently studied. To compare the Xpert assay with Roche and to assess its use in the HIV clinical laboratory. A total of 383 plasma samples of HIV-1 infected patients previously tested by Roche, were retrospectively tested by Xpert to determine concordance between the two assays. Samples included a diversity of HIV-1 subtypes and a wide range of VLs. There was a high concordance between the two assays, except for a CRF02_AG subtype variant with high VL titters, that was detected by Roche but undetected by Xpert. The 5' long terminal repeat gene region of this virus, targeted by the Xpert assay, was amplified and sequenced. A 25 nucleotide insert was identified, but was unmatched to any known sequences of HIV-1. This particular insert, however could not explain the false-negativity by the Xpert assay. This study underlines the challenge to routine VL testing due to the high genetic diversity of HIV-1. Clinicians should, therefore be advised that a negative VL in cases where the clinical picture does not match the laboratory report, might in fact be, a false-negative result of the VL assay. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. Significant reduction of peripheral blood interleukin-35 and CD4+EBI3+ T cells, which are negatively correlated with an increase in the plasma IL-17 and cTnI level, in viral myocarditis patients

    Directory of Open Access Journals (Sweden)

    Han Ouyang

    2017-02-01

    Full Text Available Introduction: Viral myocarditis (VMC has become an increasingly common heart disease that endangers human health. In the present study, the plasma interleukin-35 (IL-35 level and the percentage of CD4 + EBI3 + T cells in VMC patients were detected to investigate the significance of changes in these parameters in the plasma of VMC patients and their association with the disease. Material and methods: ELISA was performed to detect the plasma IL-35 level and the percentage of peripheral blood CD4 + EBI3 + T cells in 40 VMC patients and in 20 healthy individuals. Moreover, the plasma IL-17 levels in the VMC patients and in the healthy individuals were detected using an ELISA, and the cardiac Troponin-I (cTnI levels were detected using a chemiluminescent microparticle immunoassay to compare the differences in the groups. Results : Plasma IL-35 level and the percentage of CD4 + EBI3 + T cells in acute phase VMC patients was lower than that in the healthy control group and the convalescent phase VMC patients. Additionally, the plasma IL-35 level in the VMC patients exhibited a negative correlation with the levels of cTnI and IL-17. The percentage of CD4 + EBI3 + T cells also showed a negative correlation with the levels of cTnI and IL-17. Conclusions : The plasma IL-35 level and the percentage of CD4 + EBI3 + T cells in VMC patients was reduced, and the amount of the decrease was associated with the severity of the disease. These results suggest that IL-35 and CD4 + EBI3 + T might play important roles in the progression of VMC and could be used as indictors of the disease.

  20. IP-10 predicts the first phase decline of HCV RNA and overall viral response to therapy in patients co-infected with chronic hepatitis C virus infection and HIV

    DEFF Research Database (Denmark)

    Falconer, Karolin; Askarieh, Galia; Weis, Nina Margrethe

    2010-01-01

    The aim of this study was to investigate the utility of baseline plasma interferon-gamma inducible protein-10 (IP-10) levels in human immunodeficiency virus (HIV)-hepatitis C virus (HCV) co-infected patients. Baseline IP-10 was monitored during HCV combination therapy in 21 HIV-HCV co-infected...... patients (HCV genotype 1 (n = 16), 2 (n = 2), and 3 (n = 3)). Lower baseline IP-10 was significantly associated with a rapid decline in HCV RNA, in particular with the first phase reduction, and similar cut-off levels ( 600 pg/ml) as in HCV mono-infected patients apply. In conclusion, baseline IP......-10 infected patients, and may thus be useful in encouraging such difficult-to-treat patients to initiate therapy....

  1. Viral Reservoirs in Lymph Nodes of FIV-Infected Progressor and Long-Term Non-Progressor Cats during the Asymptomatic Phase.

    Directory of Open Access Journals (Sweden)

    C D Eckstrand

    Full Text Available Examination of a cohort of cats experimentally infected with feline immunodeficiency virus (FIV for 5.75 years revealed detectable proviral DNA in peripheral blood mononuclear cells (PBMCs harvested during the asymptomatic phase, undetectable plasma viral RNA (FIV gag, and rarely detectable cell-associated viral RNA. Despite apparent viral latency in peripheral CD4+ T cells, circulating CD4+ T cell numbers progressively declined in progressor animals. The aim of this study was to explore this dichotomy of peripheral blood viral latency in the face of progressive immunopathology. The viral replication status, cellular immunophenotypes, and histopathologic features were compared between popliteal lymph nodes (PLNs and peripheral blood. Also, we identified and further characterized one of the FIV-infected cats identified as a long-term non-progressor (LTNP.PLN-derived leukocytes from FIV-infected cats during the chronic asymptomatic phase demonstrated active viral gag transcription and FIV protein translation as determined by real-time RT-PCR, Western blot and in situ immunohistochemistry, whereas viral RNA in blood leukocytes was either undetectable or intermittently detectable and viral protein was not detected. Active transcription of viral RNA was detectable in PLN-derived CD4+ and CD21+ leukocytes. Replication competent provirus was reactivated ex vivo from PLN-derived leukocytes from three of four FIV-infected cats. Progressor cats showed a persistent and dramatically decreased proportion and absolute count of CD4+ T cells in blood, and a decreased proportion of CD4+ T cells in PLNs. A single long-term non-progressor (LTNP cat persistently demonstrated an absolute peripheral blood CD4+ T cell count indistinguishable from uninfected animals, a lower proviral load in unfractionated blood and PLN leukocytes, and very low amounts of viral RNA in the PLN.Collectively our data indicates that PLNs harbor important reservoirs of ongoing viral

  2. 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

  3. 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

  4. Improved detection of CXCR4-using HIV by V3 genotyping: application of population-based and "deep" sequencing to plasma RNA and proviral DNA.

    Science.gov (United States)

    Swenson, Luke C; Moores, Andrew; Low, Andrew J; Thielen, Alexander; Dong, Winnie; Woods, Conan; Jensen, Mark A; Wynhoven, Brian; Chan, Dennison; Glascock, Christopher; Harrigan, P Richard

    2010-08-01

    Tropism testing should rule out CXCR4-using HIV before treatment with CCR5 antagonists. Currently, the recombinant phenotypic Trofile assay (Monogram) is most widely utilized; however, genotypic tests may represent alternative methods. Independent triplicate amplifications of the HIV gp120 V3 region were made from either plasma HIV RNA or proviral DNA. These underwent standard, population-based sequencing with an ABI3730 (RNA n = 63; DNA n = 40), or "deep" sequencing with a Roche/454 Genome Sequencer-FLX (RNA n = 12; DNA n = 12). Position-specific scoring matrices (PSSMX4/R5) (-6.96 cutoff) and geno2pheno[coreceptor] (5% false-positive rate) inferred tropism from V3 sequence. These methods were then independently validated with a separate, blinded dataset (n = 278) of screening samples from the maraviroc MOTIVATE trials. Standard sequencing of HIV RNA with PSSM yielded 69% sensitivity and 91% specificity, relative to Trofile. The validation dataset gave 75% sensitivity and 83% specificity. Proviral DNA plus PSSM gave 77% sensitivity and 71% specificity. "Deep" sequencing of HIV RNA detected >2% inferred-CXCR4-using virus in 8/8 samples called non-R5 by Trofile, and <2% in 4/4 samples called R5. Triplicate analyses of V3 standard sequence data detect greater proportions of CXCR4-using samples than previously achieved. Sequencing proviral DNA and "deep" V3 sequencing may also be useful tools for assessing tropism.

  5. Viral activation of MK2-hsp27-p115RhoGEF-RhoA signaling axis causes cytoskeletal rearrangements, p-body disruption and ARE-mRNA stabilization.

    Directory of Open Access Journals (Sweden)

    Jennifer A Corcoran

    2015-01-01

    Full Text Available Kaposi's sarcoma-associated herpesvirus (KSHV is the infectious cause of several AIDS-related cancers, including the endothelial cell (EC neoplasm Kaposi's sarcoma (KS. KSHV-infected ECs secrete abundant host-derived pro-inflammatory molecules and angiogenic factors that contribute to tumorigenesis. The precise contributions of viral gene products to this secretory phenotype remain to be elucidated, but there is emerging evidence for post-transcriptional regulation. The Kaposin B (KapB protein is thought to contribute to the secretory phenotype in infected cells by binding and activating the stress-responsive kinase MK2, thereby selectively blocking decay of AU-rich mRNAs (ARE-mRNAs encoding pro-inflammatory cytokines and angiogenic factors. Processing bodies (PBs are cytoplasmic ribonucleoprotein foci in which ARE-mRNAs normally undergo rapid 5' to 3' decay. Here, we demonstrate that PB dispersion is a feature of latent KSHV infection, which is dependent on kaposin protein expression. KapB is sufficient to disperse PBs, and KapB-mediated ARE-mRNA stabilization could be partially reversed by treatments that restore PBs. Using a combination of genetic and chemical approaches we provide evidence that KapB-mediated PB dispersion is dependent on activation of a non-canonical Rho-GTPase signaling axis involving MK2, hsp27, p115RhoGEF and RhoA. PB dispersion in latently infected cells is likewise dependent on p115RhoGEF. In addition to PB dispersion, KapB-mediated RhoA activation in primary ECs caused actin stress fiber formation, increased cell motility and angiogenesis; these effects were dependent on the activity of the RhoA substrate kinases ROCK1/2. By contrast, KapB-mediated PB dispersion occurred in a ROCK1/2-independent manner. Taken together, these observations position KapB as a key contributor to viral reprogramming of ECs, capable of eliciting many of the phenotypes characteristic of KS tumor cells, and strongly contributing to the post

  6. Increased Levels of Cell-Free Human Placental Lactogen mRNA at 28-32 Gestational Weeks in Plasma of Pregnant Women With Placenta Previa and Invasive Placenta

    Science.gov (United States)

    Sekizawa, Akihiko; Ventura, Walter; Koide, Keiko; Hori, Kyouko; Okai, Takashi; Masashi, Yoshida; Furuya, Kenichi; Mizumoto, Yoshifumi

    2014-01-01

    We compared the levels of cell-free human placental lactogen (hPL) messenger RNA (mRNA) in maternal plasma at 28 to 32 weeks of gestation between women with diagnosis of placenta previa or invasive placenta and women with an uneventful pregnancy. Sensitivity and specificity of hPL mRNA for the prediction of invasive placenta were further explored. Plasma hPL mRNA were quantified by real-time reverse-transcriptase polymerase chain reaction in women with placenta previa (n = 13), invasive placenta (n = 5), and normal pregnancies (n = 92). Median (range) hPL mRNA was significantly higher in women with placenta previa, 782 (10-2301) copies/mL of plasma, and in those with invasive placenta, 615 (522-2102) copies/mL of plasma, when compared to normal pregnancies, 90 (4-4407) copies/mL of plasma, P < .01 and P < .05, respectively. We found a sensitivity of 100% and a specificity of 61.5% for the prediction of invasive placenta among women with placenta previa. In conclusion, expression of hPL mRNA is increased in plasma of women with placenta previa and invasive placenta at 28 to 32 weeks of gestation. PMID:23744883

  7. PAI-1 mRNA expression and plasma level in rheumatoid arthritis: relationship with 4G/5G PAI-1 polymorphism.

    Science.gov (United States)

    Muñoz-Valle, José Francisco; Ruiz-Quezada, Sandra Luz; Oregón-Romero, Edith; Navarro-Hernández, Rosa Elena; Castañeda-Saucedo, Eduardo; De la Cruz-Mosso, Ulises; Illades-Aguiar, Berenice; Leyva-Vázquez, Marco Antonio; Castro-Alarcón, Natividad; Parra-Rojas, Isela

    2012-12-01

    Rheumatoid arthritis (RA) is a chronic inflammatory disease affecting the synovial membrane, cartilage and bone. PAI-1 is a key regulator of the fibrinolytic system through which plasminogen is converted to plasmin. The plasmin activates the matrix metalloproteinase system, which is closely related with the joint damage and bone destruction in RA. The aim of this study was to investigate the relationship between 4G/5G PAI-1 polymorphism with mRNA expression and PAI-1 plasma protein levels in RA patients. 113 RA patients and 123 healthy subjects (HS) were included in the study. The 4G/5G PAI-1 polymorphism was determined by polymerase chain reaction-restriction fragment length polymorphism method; the PAI-1 mRNA expression was determined by real-time PCR; and the soluble PAI-1 (sPAI-1) levels were quantified using an ELISA kit. No significant differences in the genotype and allele frequencies of 4G/5G PAI-1 polymorphism were found between RA patients and HS. However, the 5G/5G genotype was the most frequent in both studied groups: RA (42%) and HS (44%). PAI-1 mRNA expression was slightly increased (0.67 fold) in RA patients with respect to HS (P = 0.0001). In addition, in RA patients, the 4G/4G genotype carriers showed increased PAI-1 mRNA expression (3.82 fold) versus 4G/5G and 5G/5G genotypes (P = 0.0001), whereas the sPAI-1 plasma levels did not show significant differences. Our results indicate that the 4G/5G PAI-1 polymorphism is not a marker of susceptibility in the Western Mexico. However, the 4G/4G genotype is associated with high PAI-1 mRNA expression but not with the sPAI-1 levels in RA patients.

  8. Crop-associated virus reduces the rooting depth of non-crop perennial native grass more than non-crop-associated virus with known viral suppressor of RNA silencing (VSR).

    Science.gov (United States)

    Malmstrom, Carolyn M; Bigelow, Patrick; Trębicki, Piotr; Busch, Anna K; Friel, Colleen; Cole, Ellen; Abdel-Azim, Heba; Phillippo, Colin; Alexander, Helen M

    2017-09-15

    As agricultural acreage expanded and came to dominate landscapes across the world, viruses gained opportunities to move between crop and wild native plants. In the Midwestern USA, virus exchange currently occurs between widespread annual Poaceae crops and remnant native perennial prairie grasses now under consideration as bioenergy feedstocks. In this region, the common aphid species Rhopalosiphum padi L. (the bird cherry-oat aphid) transmits several virus species in the family Luteoviridae, including Barley yellow dwarf virus (BYDV-PAV, genus Luteovirus) and Cereal yellow dwarf virus (CYDV-RPV and -RPS, genus Polerovirus). The yellow dwarf virus (YDV) species in these two genera share genetic similarities in their 3'-ends, but diverge in the 5'-regions. Most notably, CYDVs encode a P0 viral suppressor of RNA silencing (VSR) absent in BYDV-PAV. Because BYDV-PAV has been reported more frequently in annual cereals and CYDVs in perennial non-crop grasses, we examine the hypothesis that the viruses' genetic differences reflect different affinities for crop and non-crop hosts. Specifically, we ask (i) whether CYDVs might persist within and affect a native non-crop grass more strongly than BYDV-PAV, on the grounds that the polerovirus VSR could better moderate the defenses of a well-defended perennial, and (ii) whether the opposite pattern of effects might occur in a less defended annual crop. Because previous work found that the VSR of CYDV-RPS possessed greater silencing suppressor efficiency than that of CYDV-RPV, we further explored (iii) whether a novel grass-associated CYDV-RPS isolate would influence a native non-crop grass more strongly than a comparable CYDV-RPV isolate. In growth chamber studies, we found support for this hypothesis: only grass-associated CYDV-RPS stunted the shoots and crowns of Panicum virgatum L. (switchgrass), a perennial native North American prairie grass, whereas crop-associated BYDV-PAV (and coinfection with BYDV-PAV and CYDV-RPS) most

  9. Single-cycle immunodeficiency viruses provide strategies for uncoupling in vivo expression levels from viral replicative capacity and for mimicking live-attenuated SIV vaccines

    International Nuclear Information System (INIS)

    Kuate, Seraphin; Stahl-Hennig, Christiane; Haaft, Peter ten; Heeney, Jonathan; Ueberla, Klaus

    2003-01-01

    To reduce the risks associated with live-attenuated immunodeficiency virus vaccines, single-cycle immunodeficiency viruses (SCIVs) were developed by primer complementation and production of the vaccine in the absence of vif in a vif-independent cell line. After a single intravenous injection of SCIVs into rhesus monkeys, peak viral RNA levels of 10 3 to 10 4 copies/ml plasma were observed, indicating efficient expression of SCIV in the vaccinee. After booster immunizations with SCIVs, SIV-specific humoral and cellular immune responses were observed. Although the vaccine doses used in this pilot study could not protect vaccinees from subsequent intravenous challenge with pathogenic SIVmac239, our results demonstrate that the novel SCIV approach allows us to uncouple in vivo expression levels from the viral replicative capacity facilitating the analysis of the relationship between viral expression levels or viral genes and immune responses induced by SIV

  10. Association of suboptimal health status with psychosocial stress, plasma cortisol and mRNA expression of glucocorticoid receptor α/β in lymphocyte.

    Science.gov (United States)

    Yan, Yu-Xiang; Dong, Jing; Liu, You-Qin; Zhang, Jie; Song, Man-Shu; He, Yan; Wang, Wei

    2015-01-01

    Suboptimal health status (SHS) has become a new public health challenge in China. This study investigated whether high SHS is associated with psychosocial stress, changes in cortisol level and/or glucocorticoid receptor (GR) isoform expression. Three-hundred eighty-six workers employed in three companies in Beijing were recruited. The SHS score was derived from data collection in the SHS questionnaire (SHSQ-25). The short standard version of the Copenhagen Psychosocial Questionnaire (COPSOQ) was used to assess job-related psychosocial stress. The mean value of the five scales of COPSOQ and distribution of plasma cortisol and mRNA expression of GRα/GRβ between the high level of SHS group and the low level of SHS group were compared using a general linear model procedure. Multiple linear regression analysis was used to analyze the effect of psychosocial stress on SHS. We identified three factors that were predictive of SHS, including "demands at work", "interpersonal relations and leadership" and "insecurity at work". Significantly higher levels of plasma cortisol and GRβ/GRα mRNA ratio were observed among the high SHS group. High level of SHS is associated with decreased mRNA expression of GRα. This study confirmed the association between chronic psychosocial stress and SHS, indicating that improving the psychosocial work environment may reduce SHS and then prevent chronic diseases effectively.

  11. Differences in HIV Type 1 RNA Plasma Load Profile of Closely Related Cocirculating Ethiopian Subtype C Strains: C and C '

    NARCIS (Netherlands)

    Ayele, Workenesh; Mekonnen, Yared; Messele, Tsehaynesh; Mengistu, Yohannes; Tsegaye, Aster; Bakker, Margreet; Berkhout, Ben; Dorigo-Zetsma, Wendelien; Wolday, Dawit; Goudsmit, Jaap; Coutinho, Roel; de Baar, Michel; Paxton, William A.; Pollakis, Georgios

    2010-01-01

    Two HIV-1 subtype C subclusters have been identified in Ethiopia (C and C') with little knowledge regarding their biological or clinical differences. We longitudinally monitored HIV-1 viral loads and CD4(+) T cell counts for 130 subtype C-infected individuals from Ethiopia over 5 years. The genetic

  12. Zinc-mediated binding of a low-molecular-weight stabilizer of the host anti-viral factor apolipoprotein B mRNA-editing enzyme, catalytic polypeptide-like 3G.

    Science.gov (United States)

    Radwan, Mohamed O; Sonoda, Sachiko; Ejima, Tomohiko; Tanaka, Ayumi; Koga, Ryoko; Okamoto, Yoshinari; Fujita, Mikako; Otsuka, Masami

    2016-09-15

    Apolipoprotein B mRNA-editing enzyme, catalytic polypeptide-like 3G (APOBEC3G, A3G), is a human anti-virus restriction protein which works deaminase-dependently and -independently. A3G is known to be ubiquitinated by HIV-1 viral infectivity factor (Vif) protein, leading to proteasomal degradation. A3G contains two zinc ions at the N-terminal domain and the C-terminal domain. Four lysine residues, K(297), K(301), K(303), and K(334), are known to be required for Vif-mediated A3G ubiquitination and degradation. Previously, we reported compound SN-1, a zinc chelator that increases steady-state expression level of A3G in the presence of Vif. In this study, we prepared Biotin-SN-1, a biotinylated derivative of SN-1, to study the SN-1-A3G interaction. A pull-down assay revealed that Biotin-SN-1 bound A3G. A zinc-abstraction experiment indicated that SN-1 binds to the zinc site of A3G. We carried out a SN-1-A3G docking study using molecular operating environment. The calculations revealed that SN-1 binds to the C-terminal domain through Zn(2+), H(216), P(247), C(288), and Y(315). Notably, SN-1-binding covers the H(257), E(259), C(288), and C(291) residues that participate in zinc-mediated deamination, and the ubiquitination regions of A3G. The binding of SN-1 presumably perturbs the secondary structure between C(288) and Y(315), leading to less efficient ubiquitination. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Comparison of HPV detection technologies: Hybrid capture 2, PreTect HPV-Proofer and analysis of HPV DNA viral load in HPV16, HPV18 and HPV33 E6/E7 mRNA positive specimens.

    LENUS (Irish Health Repository)

    Keegan, Helen

    2012-02-01

    Human papillomavirus (HPV) testing using molecular methods in liquid based cytology (LBC) specimens may be useful as an adjunct to cervical screening by cytology. We compared the positivity rate of the commercially available HPV DNA method hybrid capture 2 (hc2) and the commercially available E6\\/E7 mRNA method PreTect HPV-Proofer in cytological specimens (n=299). LBC specimens collected (n=299) represented the following cervical cytological disease categories: Normal (n=60), borderline nuclear abnormalities (BNA) (n=34), CIN1 (n=121), CIN2 (n=60), CIN3 (n=24). Overall, 69% (205\\/299) of the cases were positive by hc2 and 38% (112\\/299) of the cases were positive by PreTect HPV-Proofer. Concordance rates between the two tests were highest in the high-grade cytology cases (CIN2: 67% and CIN3: 83%) and the normal cytology cases (88%) and lowest in the BNA and CIN1 categories (56% and 52%). HPV DNA viral load analyses were carried out on HPV16 (n=55), HPV18 (n=9) and HPV33 (n=13) samples that were positive by PreTect HPV-Proofer. The sensitivity and specificity of PreTect HPV-Proofer and the hc2 DNA test for the detection of high-grade cytology (i.e. CIN2+) were 71.4% and 75.8% vs 100% and 43.7%, respectively. The relatively low detection rate observed by PreTect HPV-Proofer in the whole range of cytological positive cases, combined with a relatively higher specificity and PPV, suggests that PreTect HPV-Proofer may be more useful than hc2 for triage and in predicting high-grade disease.

  14. Rapid and highly fieldable viral diagnostic

    Energy Technology Data Exchange (ETDEWEB)

    McKnight, Timothy E.

    2016-12-20

    The present invention relates to a rapid, highly fieldable, nearly reagentless diagnostic to identify active RNA viral replication in a live, infected cells, and more particularly in leukocytes and tissue samples (including biopsies and nasal swabs) using an array of a plurality of vertically-aligned nanostructures that impale the cells and introduce a DNA reporter construct that is expressed and amplified in the presence of active viral replication.

  15. Cervical Shedding of HIV-1 RNA Among Women With Low Levels of Viremia While Receiving Highly Active Antiretroviral Therapy

    Science.gov (United States)

    Neely, Michael N.; Benning, Lorie; Xu, Jiaao; Strickler, Howard D.; Greenblatt, Ruth M.; Minkoff, Howard; Young, Mary; Bremer, James; Levine, Alexandra M.; Kovacs, Andrea

    2011-01-01

    Background Among women with low o r undetectable quantities of HIV-1 RNA in plasma, factors associated with genital HIV-1 RNA shedding, including choice of treatment regimen, are poorly characterized. Methods We measured HIV-1 RNA in cervical swab specimens obtained from participants in the Women’s Interagency HIV Study who had concurrent plasma viral RNA levels <500 copies/mL, and we assessed factors associated with genital HIV shedding. The study was powered to determine the relative effects of antiretroviral protease inhibitors (PIs) versus nonnucleoside reverse transcriptase inhibitors (NNRTIs) on viral RNA shedding. Results Overall, 44 (15%) of 290 women had detectable HIV-1 RNA in cervical specimens. In the final multivariate model, shedding was independently associated with NNRTI (vs. PI) use (odds ratio [OR], 95% confidence interval [CI]: 2.24, 1.13 to 4.45) and illicit drug use (OR, 95% CI: 2.41, 0.96 to 5.69). Conclusions This is the largest study to define risks for genital HIV-1 RNA shedding in women with low/undetectable plasma virus. Shedding in this population was common, and NNRTI-based highly active antiretroviral therapy (HAART) (vs. PI-based HAART) was associated with genital HIV shedding. Further study is required to determine the impact of these findings on transmission of HIV from mother to child or to sexual partners. PMID:17106279

  16. Identification of miR-93 as a suitable miR for normalizing miRNA in plasma of tuberculosis patients.

    Science.gov (United States)

    Barry, Simone E; Chan, Brian; Ellis, Magda; Yang, YuRong; Plit, Marshall L; Guan, Guangyu; Wang, Xiaolin; Britton, Warwick J; Saunders, Bernadette M

    2015-07-01

    Tuberculosis (TB) remains a major public health issue. New tests to aid diagnoses and monitor the response to therapy are urgently required. There is growing interest in the use of microRNA (miRNA) profiles as diagnostic, prognostic or predictive markers in a range of clinical and infectious diseases, including Mycobacterium tuberculosis infection, however, challenges exist to accurately normalise miRNA levels in cohorts. This study examined the appropriateness of 12 miRs and RNU6B to normalise circulating plasma miRNA levels in individuals with active TB from 2 different geographical and ethnic regions. Twelve miRs (let-7, miR-16, miR-22, miR-26, miR-93, miR-103, miR-191, miR-192, miR-221, miR-423, miR-425 and miR-451) and RNU6B were selected based on their reported production by lung cells, expression in blood and previous use as a reference miRNA. Expression levels were analysed in the plasma of newly diagnosed TB patients from Australia and China compared with individuals with latent TB infection and healthy volunteers. Analysis with both geNorm and NormFinder software identified miR-93 as the most suitable reference miR in both cohorts, either when analysed separately or collectively. Interestingly, there were large variations in the expression levels of some miRs, in particular miR-192 and let-7, between the two cohorts, independent of disease status. These data identify miR-93 is a suitable reference miR for normalizing miRNA levels in TB patients, and highlight how environmental, and possibly ethnic, factors influence miRNA expression levels, demonstrating the necessity of assessing the suitability of reference miRs within the study population. © 2015 The Authors. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for Cellula