Publications by year
Imrie RM, Roberts KE, Longdon B
(In Press). Between virus correlations in the outcome of infection across host species: evidence of virus genotype by host species interactions.
Between virus correlations in the outcome of infection across host species: evidence of virus genotype by host species interactions
AbstractVirus host shifts are a major source of outbreaks and emerging infectious diseases, and predicting the outcome of novel host and virus interactions remains a key challenge for virus research. The evolutionary relationships between host species can explain variation in transmission rates, virulence, and virus community composition between hosts, but the potential for different viruses to interact with host species effects has yet to be established. Here, we measure correlations in viral load of four Cripavirus isolates across experimental infections of 45 Drosophilidae host species. We find positive correlations between every pair of viruses tested, suggesting that broadly susceptible host clades could act as reservoirs and donors for certain types of viruses. Additionally, we find evidence of genotype-by-genotype interactions between viruses and host species, highlighting the importance of both host and virus traits in determining the outcome of virus host shifts. More closely related viruses tended to be more strongly correlated, providing tentative evidence that virus evolutionary relatedness may be a useful proxy for determining the likelihood of novel virus emergence, which warrants further research.Impact SummaryMany new infectious diseases are caused by viruses jumping into novel host species. Estimating the probability that jumps will occur, what the characteristics of new viruses will be, and how they are likely to evolve after jumping to new host species are major challenges. To solve these challenges, we require a detailed understanding of the interactions between different viruses and hosts, or metrics that can capture some of the variation in these interactions. Previous studies have shown that the evolutionary relationships between host species can be used to predict traits of infections in different hosts, including transmission rates and the damage caused by infection. However, the potential for different viruses to influence the patterns of these host species effects has yet to be determined. Here, we use four viruses of insects in experimental infections across 45 different fruit fly host species to begin to answer this question. We find similarities in the patterns of replication and persistence between all four viruses, suggesting susceptible groups of related hosts could act as reservoirs and donors for certain types of virus. However, we also find evidence that different virus genotypes interact in different ways with some host species. Viruses that were more closely related tended to behave in similar ways, and so we suggest that virus evolutionary relatedness may prove to be a useful metric for predicting the traits of novel infections and should be explored further in future studies. Abstract
Baril T, Imrie RM, Hayward A
(In Press). Earl Grey: a fully automated user-friendly transposable element annotation and analysis pipeline.
Earl Grey: a fully automated user-friendly transposable element annotation and analysis pipeline
ABSTRACTBackgroundTransposable elements (TEs) are found in nearly all eukaryotic genomes and are implicated in a range of evolutionary processes. Despite considerable research attention on TEs, their annotation and characterisation remain challenging, particularly for non-specialists. Current methods of automated TE annotation are subject to several issues that can reduce their overall quality: (i) fragmented and overlapping TE annotations may lead to erroneous estimates of TE count and coverage; (ii) repeat models may represent small proportions of their total length, where 5’ and 3’ regions are poorly captured; (iii) resultant libraries may contain redundancy, with the same TE family represented more than once. Existing pipelines can also be challenging to install, run, and extract data from. To address these issues, we present Earl Grey: a fully automated transposable element annotation pipeline designed for the user-friendly curation and annotation of TEs in eukaryotic genome assemblies.ResultsUsing a simulated genome, three model genome assemblies, and three non-model genome assemblies, Earl Grey outperforms current widely used TE annotation methodologies in ameliorating the issues mentioned above by producing longer TE consensus sequences in non-redundant TE libraries, which are then used to produce less fragmented TE annotations without the presence of overlaps. Earl Grey scores highly in benchmarking for TE annotation (MCC: 0.99) and classification (97% correctly classified) in comparison to existing software.ConclusionsEarl Grey provides a comprehensive and fully automated TE annotation toolkit that provides researchers with paper-ready summary figures and outputs in standard formats compatible with other bioinformatics tools. Earl Grey has a modular format, with great scope for the inclusion of additional modules focussed on further quality control aspects and tailored analyses in future releases. Abstract
Imrie RM, Walsh SK, Roberts KE, Lello J, Longdon B
(In Press). Investigating the outcomes of virus coinfection within and across host species.
Investigating the outcomes of virus coinfection within and across host species
AbstractInteractions between coinfecting pathogens have the potential to alter the course of infection and can act as a source of phenotypic variation in susceptibility between hosts. This phenotypic variation may influence the evolution of host-pathogen interactions within host species and interfere with patterns in the outcomes of infection across host species. Here, we examine experimental coinfections of twoCripaviruses– Cricket Paralysis Virus (CrPV), and Drosophila C Virus (DCV) –across a panel of 25Drosophila melanogasterinbred lines and 47Drosophilidaehost species. We find that interactions between these viruses alter viral loads acrossD. melanogastergenotypes, with a ~3 fold increase in the viral load of DCV and a ~2.5 fold decrease in CrPV in coinfection compared to single infection, but we find little evidence of a host genetic basis for these effects. Across host species, we find no evidence of systematic changes in susceptibility during coinfection, with no interaction between DCV and CrPV detected in the majority of host species. These results suggest that phenotypic variation in coinfection interactions within host species can occur independently of natural host genetic variation in susceptibility, and that patterns of susceptibility across host species to single infections can be robust to the added complexity of coinfection. Abstract
Walsh SK, Imrie RM, Matuszewska M, Paterson GK, Weinert LA, Hadfield JD, Buckling A, Longdon B
(In Press). The host phylogeny determines viral infectivity and replication across<i>Staphylococcus</i>host species.
The host phylogeny determines viral infectivity and replication acrossStaphylococcushost species
AbstractGenetic similarity between eukaryotic host species is an important determinant of the outcome of virus host shifts, where a pathogen infects a novel host species. However, it is less clear if this is the case for prokaryotes where anti-virus defences can be transmitted by horizontal gene transfer and evolve rapidly. Understanding the patterns and determinants of cross-species transmissions may provide insights into the processes underlying pathogen emergence. Here, we measure the susceptibility of 64 strains ofStaphylococcusbacteria (48 strains ofS. aureusand 16 non-aureusspecies) to the bacteriophage ISP, which is currently under investigation for use in phage therapy. Using three methods – plaque assays, optical density (OD) assays, and quantitative (q)PCR – we find that the host phylogeny explains a large proportion of the variation in susceptibility to ISP across the host panel. These patterns were consistent in models of onlyS. aureusstrains and models with a single representative from eachStaphylococcusspecies, suggesting that these phylogenetic effects are conserved both within and among host species. We find positive correlations between susceptibility assessed using a binary measure of plaque assay, OD, and qPCR, but not between the continuous component of plaque assay and any other method, suggesting that plaque assays alone may be inadequate to assess host range. Together, our results demonstrate the ability of bacterial host evolutionary relatedness to explain differences in susceptibility to phage infection, with implications for the development of ISP both as a phage therapy treatment and as an experimental system for the study of virus host shifts. Abstract
Imrie RM, Roberts KE, Longdon B (2021). Between virus correlations in the outcome of infection across host species: Evidence of virus by host species interactions. Evolution Letters, 5(5), 472-483.