1,583 research outputs found
The NS3 protein of rice hoja blanca virus suppresses RNA silencing in mammalian cells
The NS3 protein of the tenuivirus rice hoja blanca virus (RHBV) has previously been shown to represent the viral RNA interference (RNAi) suppressor and is active in both plant and insect cells by binding short interfering RNAs (siRNAs) in vitro. Using a firefly luciferase-based silencing assay it is described here that NS3 is also active in mammalian cells. This activity is independent of the inducer molecule used. Using either synthetic siRNAs or a short hairpin RNA construct, NS3 was able to significantly suppress the RNAi-mediated silencing of luciferase expression in both monkey (Vero) and human (HEK293) cells. These results support the proposed mode of action of NS3 to act by sequestering siRNAs, the key molecules of the RNAi pathway conserved in all eukaryotes. The possible applications of this protein in modulating RNAi and investigating the proposed antiviral RNAi response in mammalian cell systems are discussed
Binding of small interfering RNA molecules is crucial for RNA interference suppressor activity of rice hoja blanca virus NS3 in plants
The NS3 protein of rice hoja blanca tenuivirus represents a viral suppressor of RNAi that sequesters small interfering (si)RNAs in vitro. To determine whether this siRNA binding property is the critical determinant for the suppressor activity of NS3, an alanine point mutational analysis was performed and the resulting mutant proteins were tested for both siRNA binding ability and RNAi suppressor activity in plants. Alanine substitutions of lysine residues at position 173-175 resulted in mutant proteins that lost both their affinity for siRNAs and their RNAi suppressor activity in planta. This indicates that siRNA binding of NS3 is indeed essential for the suppressor function of NS3 and that residues at position 173-175 are involved in the siRNA binding and suppressor activit
Video and vision: videography of a Marian apparition
Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG geförderten) Allianz- bzw. Nationallizenz frei zugänglich.This publication is with permission of the rights owner freely accessible due to an Alliance licence and a national licence (funded by the DFG, German Research Foundation) respectively.In this article, we sketch the field of qualitative video-analysis and locate videography within this. Instead of presenting the methods of videography formally, we illustrate the application of this method in a particular field: Marian apparitions occurring in a German town in 1999, captured live on video. The presentation of the method in this paper follows a general methodological structure. (1) We first outline the ethnographic context of the setting in which the video-recordings were made. This context includes actors, religious associations, and locations as well as some aspects of the apparitional events' historical genesis. (2) We then turn to look at the performance of the Marian vision as recorded in the video. By applying sequential analysis, we roughly identify a temporal order to the event, which exhibits an interesting deviation from earlier forms of apparitions due to the way it takes a subjectively spiritual form. This finding leads us to finally (3) address the role of the subjective perspective that, as we argue, is a further essential dimension of videography. It is on this level that we are made aware of the relevance of the life-world as a methodological background for the kind of interpretive social science that takes the actor's perspective into account
How do biological and social kinship play out within families in the U.S.? An evolutionary perspective on perceived parental care and closeness in adolescents
"Abgeleitet aus der Theorie der Verwandtenselektion sagen Evolutionsbiologen vorher, dass Individuen gegenüber ihren biologischen Kindern mehr Fürsorge zeigen sollten als gegenüber Kindern, zu denen eine soziale Elternschaft besteht. Entsprechend wird erwartet, dass biologische Kinder die Beziehungen zu ihren Eltern besser einschätzen als Stiefkinder. Zur Überprüfung dieser Hypothese ziehen wir die Daten der U.S. National Longitudinal Study of Adolescent Health (Add Health) heran. Diese Studie erlaubt es, im Gegensatz zu vielen anderen Datenquellen, die Konsequenzen der innerfamilialen Dynamik sozialer und biologischer Eltern-Kind-Beziehungen zu untersuchen. Um diesen Vergleich innerhalb der Familien zu ermöglichen, untersuchen wir Geschwisterdyaden und führen eine fixed-effects-Regression durch. Die Resultate der deskriptiven und der multivariaten Analysen bestätigen, dass der Status biologischer Elternschaft auch dann die Beziehungseinschätzungen der Jugendlichen (wahrgenommene elterliche Fürsorge und emotionale Nähe) vorhersagt, wenn für andere relevante Einflussfaktoren kontrolliert wird - sowohl in Bezug auf die väterliche als auch auf die mütterliche Beziehung. In der Diskussion kommentieren wir das Ergebnis im Hinblick auf eine mögliche Integration evolutionsbiologischer und soziologischer Forschungsperspektiven und schließen mit einigen Empfehlungen für die zukünftige empirische Datenerhebung ab. Eine Umsetzung dieser Empfehlungen könnte es interessierten Forscherinnen und Forschern in Zukunft ermöglichen, die relative Bedeutung biologischer und sozialer Einflüsse auf die Eltern detaillierter zu untersuchen." (Autorenreferat)"Consistent with inclusive fitness theory, evolutionary biologists predict that individuals care more for their biological than their social children and hence that biological children assess the relationships to their parents better than stepchildren. To test this assumption, we use data from the U.S. National Longitudinal Study of Adolescent Health (Add Health). Unlike many other studies that have been conducted so far, this survey allows us to analyze the consequences of the dynamic between social and biological parent-child relationships within the same families. We use comparisons of sibling pairs and fixed-effects regression to achieve the within-family comparison. Both the descriptive and multivariate regression results confirm that - even after controlling for other relevant influences - biological parenthood matters with regard to children's relationship assessments (perceived parental care and closeness of the parent-child relationship) and in both the relationships to resident fathers and mothers. In the discussion, we comment on the possible integration of the evolutionary and sociological perspectives and close with some recommendations for future data collection that could allow researchers to analyze the relative impact of biological and social influences on parent-child relationships on a more fine-grained level." (author's abstract
Videography: analysing video data as a ‘focused’ ethnographic and hermeneutical exercise
Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG geförderten) Allianz- bzw. Nationallizenz frei zugänglich.This publication is with permission of the rights owner freely accessible due to an Alliance licence and a national licence (funded by the DFG, German Research Foundation) respectively.Visual research methods are becoming increasingly important for qualitative studies. Within this dynamically expanding field, methods for analysing ‘natural’ video recordings have developed considerably over the past decades. In this article we discuss methodological aspects of general importance for any analysis of this type of video data. Being a fundamentally interpretive method, our first argument is that sequential analysis is always a hermeneutic endeavour, which requires methodical understanding. The second refers to data collection. We stress that, in addition to sequential analysis, the ethnographic dimension of video analysis should be taken into account methodologically. Video analysis requires, thirdly, a systematic account of the subjectivity, both of the actors analysed as well as of the analysts. Our arguments are grounded in extensive data from several studies, including the communicative genre of powerpoint presentations, commemoration rituals and public events. Selected data fragments are presented here to support our claims. Building upon this expertise, we propose further improvement of video analysis methodology by reflecting on our own practice of analysing video in data sessions (i.e. the ‘video analysis of video analysis’)
Corrigendum: Analysis of tick-borne encephalitis virus-induced host responses in human cells of neuronal origin and interferon-mediated protection
No abstract available
Analysis of tick-borne encephalitis virus-induced host responses in human cells of neuronal origin and interferon-mediated protection
Tick-borne encephalitis virus (TBEV) is a member of the genus Flavivirus. It can cause serious infections in humans that may result in encephalitis/meningoencephalitis. Although several studies have described the involvement of specific genes in the host response to TBEV infection in the central nervous system (CNS), the overall network remains poorly characterized. Therefore, we investigated the response of DAOY cells (human medulloblastoma cells derived from cerebellar neurons) to TBEV (Neudoerfl strain, Western subtype) infection to characterize differentially expressed genes by transcriptome analysis. Our results revealed a wide panel of interferon-stimulated genes (ISGs) and pro-inflammatory cytokines, including type III but not type I (or II) interferons (IFNs), which are activated upon TBEV infection, as well as a number of non-coding RNAs, including long non-coding RNAs. To obtain a broader view of the pathways responsible for eliciting an antiviral state in DAOY cells we examined the effect of type I and III IFNs and found that only type I IFN pre-treatment inhibited TBEV production. The cellular response to TBEV showed only partial overlap with gene expression changes induced by IFN-β treatment – suggesting a virus-specific signature – and we identified a group of ISGs that were highly up-regulated following IFN-β treatment. Moreover, a high rate of down-regulation was observed for a wide panel of pro-inflammatory cytokines upon IFN-β treatment. These data can serve as the basis for further studies of host–TBEV interactions and the identification of ISGs and/or lncRNAs with potent antiviral effects in cases of TBEV infection in human neuronal cells
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