Interactions between Cucumber mosaic virus proteins and host proteins

Cucumber mosaic virus (CMV) infects over a thousand plant species including many crops. CMV is mainly transmitted between plants by aphids, insects with probing mouthparts that introduce virus particles directly into host cells. The 2b viral suppressor of RNA silencing (VSR) encoded by CMV is a potent counterdefence and pathogenicity factor that inhibits antiviral silencing by titration of short double-stranded RNAs. The 2b VSR not only influences infection, but also host interactions with one of the main insect vectors of CMV, the generalist aphid Myzus persicae. The 2b protein disrupts microRNA-mediated regulation of host gene expression by binding ARGONAUTE 1 (AGO1). In Arabidopsis, complete inhibition of AGO1 activity is counterproductive to CMV since this triggers antibiosis against aphids and stimulates resistance mechanisms by AGO2. The CMV 1a protein (a replicase component) is able to moderate antibiosis induction by the 2b VSR. This ensures that aphid vectors are deterred from feeding but not poisoned when they feed on CMV-infected Arabidopsis plants. I found that the CMV 1a protein is able to directly inhibit the 2b-AGO1 interaction. By binding 2b protein molecules and sequestering them in processing-bodies, the 1a protein decreases the proportion of 2b protein molecules available for binding AGO1. This ameliorates 2b-induced viral symptoms and moderates the induction of aphid resistance. However, the 1a-2b protein interaction does not inhibit the VSR activity of the 2b protein. The interaction between the CMV 1a and 2b proteins represents a novel viral regulatory system for VSRs. The finding also provides a mechanism that may explain how CMV, and possibly other viruses, modulate symptom induction and manipulate host-vector interactions

Personality Profiling: How informative are social media profiles in predicting personal information?

Personality profiling has been utilised by companies for targeted advertising, political campaigns and vaccine campaigns. However, the accuracy and versatility of such models still remains relatively unknown. Consequently, we aim to explore the extent to which peoples' online digital footprints can be used to profile their Myers-Briggs personality type. We analyse and compare the results of four models: logistic regression, naive Bayes, support vector machines (SVMs) and random forests. We discover that a SVM model achieves the best accuracy of 20.95% for predicting someones complete personality type. However, logistic regression models perform only marginally worse and are significantly faster to train and perform predictions. We discover that many labelled datasets present substantial class imbalances of personal characteristics on social media, including our own. As a result, we highlight the need for attentive consideration when reporting model performance on these datasets and compare a number of methods for fixing the class-imbalance problems. Moreover, we develop a statistical framework for assessing the importance of different sets of features in our models. We discover some features to be more informative than others in the Intuitive/Sensory (p = 0.032) and Thinking/Feeling (p = 0.019) models. While we apply these methods to Myers-Briggs personality profiling, they could be more generally used for any labelling of individuals on social media.Comment: 8 pages, 6 figures. Dataset available at https://figshare.com/articles/dataset/Self-Reported_Myers-Briggs_Personality_Types_on_Twitter/2362055

Post-Giant Impact Planetesimals Sustaining Extreme Debris Disks

Extreme debris disks can show short term behaviour through the evolution and clearing of small grains produced in giant impacts, and potentially a longer period of variability caused by a planetesimal population formed from giant impact ejecta. In this paper, we present results of numerical simulations to explain how a planetesimal populated disk can supply an observed extreme debris disk with small grains. We simulated a sample of giant impacts from which we form a planetesimal population. We then use the $N$-body code {\sc Rebound} to evolve the planetesimals spatially and collisionally. We adopt a simplistic collision criteria in which we define destructive collisions to be between planetesimals with a mutual impact velocity that exceeds two times the catastrophic disruption threshold, $V^*$. We find that for some configurations, a planetesimal populated disk can produce a substantial amount of dust to sustain an observable disk. The semi-major axis at which the giant impact occurs changes the mass added to the observed disk substantially while the orientation of the impact has less of an effect. We determine how the collision rate at the collision point changes over time and show that changes in semi-major axis and orientation only change the initial collision rate of the disk. Collision rates across all disks evolve at a similar rate.Comment: 20 pages, 21 figures, 3 tables, accepted by MNRA

Love is the triumph of the imagination: daydreams about significant others are associated with increased happiness, love and connection

Social relationships and interactions contribute to daily emotional well-being. The emotional benefits that come from engaging with others are known to arise from real events, but do they also come from the imagination during daydreaming activity? Using experience sampling methodology with 101 participants, we obtained 371 reports of naturally occurring daydreams with social and non-social content and self-reported feelings before and after daydreaming. Social, but not non-social, daydreams were associated with increased happiness, love and connection and this effect was not solely attributable to the emotional content of the daydreams. These effects were only present when participants were lacking in these feelings before daydreaming and when the daydream involved imagining others with whom the daydreamer had a high quality relationship. Findings are consistent with the idea that social daydreams may function to regulate emotion: imagining close others may serve the current emotional needs of daydreamers by increasing positive feelings towards themselves and others

The cucumber mosaic virus 1a protein regulates interactions between the 2b protein and ARGONAUTE 1 while maintaining the silencing suppressor activity of the 2b protein

The cucumber mosaic virus (CMV) 2b viral suppressor of RNA silencing (VSR) is a potent counter-defense and pathogenicity factor that inhibits antiviral silencing by titration of short double-stranded RNAs. It also disrupts microRNA-mediated regulation of host gene expression by binding ARGONAUTE 1 (AGO1). But in Arabidopsis thaliana complete inhibition of AGO1 is counterproductive to CMV since this triggers another layer of antiviral silencing mediated by AGO2, de-represses strong resistance against aphids (the insect vectors of CMV), and exacerbates symptoms. Using confocal laser scanning microscopy, bimolecular fluorescence complementation, and co-immunoprecipitation assays we found that the CMV 1a protein, a component of the viral replicase complex, regulates the 2b-AGO1 interaction. By binding 2b protein molecules and sequestering them in P-bodies, the 1a protein limits the proportion of 2b protein molecules available to bind AGO1, which ameliorates 2b-induced disease symptoms, and moderates induction of resistance to CMV and to its aphid vector. However, the 1a protein-2b protein interaction does not inhibit the ability of the 2b protein to inhibit silencing of reporter gene expression in agroinfiltration assays. The interaction between the CMV 1a and 2b proteins represents a novel regulatory system in which specific functions of a VSR are selectively modulated by another viral protein. The finding also provides a mechanism that explains how CMV, and possibly other viruses, modulates symptom induction and manipulates host-vector interactions

The cucumber mosaic virus 1a protein regulates interactions between the 2b protein and ARGONAUTE 1 while maintaining the silencing suppressor activity of the 2b protein

The cucumber mosaic virus (CMV) 2b viral suppressor of RNA silencing (VSR) is a potent counter-defense and pathogenicity factor that inhibits antiviral silencing by titration of short double-stranded RNAs. It also disrupts microRNA-mediated regulation of host gene expression by binding ARGONAUTE 1 (AGO1). But in Arabidopsis thaliana complete inhibition of AGO1 is counterproductive to CMV since this triggers another layer of antiviral silencing mediated by AGO2, de-represses strong resistance against aphids (the insect vectors of CMV), and exacerbates symptoms. Using confocal laser scanning microscopy, bimolecular fluorescence complementation, and co-immunoprecipitation assays we found that the CMV 1a protein, a component of the viral replicase complex, regulates the 2b-AGO1 interaction. By binding 2b protein molecules and sequestering them in P-bodies, the 1a protein limits the proportion of 2b protein molecules available to bind AGO1, which ameliorates 2b-induced disease symptoms, and moderates induction of resistance to CMV and to its aphid vector. However, the 1a protein-2b protein interaction does not inhibit the ability of the 2b protein to inhibit silencing of reporter gene expression in agroinfiltration assays. The interaction between the CMV 1a and 2b proteins represents a novel regulatory system in which specific functions of a VSR are selectively modulated by another viral protein. The finding also provides a mechanism that explains how CMV, and possibly other viruses, modulates symptom induction and manipulates host-vector interactions

Empirical research into white racialized identities in Britain

The intellectual project of using whiteness as an explicit tool of analysis is not one that has taken root in Britain. However, there are a number of empirical studies that investigate the racialization of white identities. In this article, I look at some empirical sociological fieldwork carried out on white identities in Britain since the early 1990s and identify the key themes arising. These themes are (in)visibility, norms and values, cultural capital and integration, contingent hierarchies and Empire in the present. In Britain, a pertinent distinction is between rural and urban settings for the enactment of white identities vis-à-vis those of minorities, and there is an exploration of some of the contingency that draws the boundary between ‘white’ and ‘Other’ in different places. Areas of commonality and distinctiveness are noted in terms of the American work. In the last section, I argue that there are a number of issues to resolve around continuing such studies, including linking the micro-level to the macro-level analysis, and expanding to international comparative work

Developing serious games for cultural heritage: a state-of-the-art review

Although the widespread use of gaming for leisure purposes has been well documented, the use of games to support cultural heritage purposes, such as historical teaching and learning, or for enhancing museum visits, has been less well considered. The state-of-the-art in serious game technology is identical to that of the state-of-the-art in entertainment games technology. As a result, the field of serious heritage games concerns itself with recent advances in computer games, real-time computer graphics, virtual and augmented reality and artificial intelligence. On the other hand, the main strengths of serious gaming applications may be generalised as being in the areas of communication, visual expression of information, collaboration mechanisms, interactivity and entertainment. In this report, we will focus on the state-of-the-art with respect to the theories, methods and technologies used in serious heritage games. We provide an overview of existing literature of relevance to the domain, discuss the strengths and weaknesses of the described methods and point out unsolved problems and challenges. In addition, several case studies illustrating the application of methods and technologies used in cultural heritage are presented

Accelerating Policy Decisions to Adopt Haemophilus influenzae Type b Vaccine: A Global, Multivariable Analysis

Jessica Shearer and colleagues analyze data from 147 countries to identify factors that influence the time taken to introduce routine vaccination against Haemophilus influenzae type b (Hib)