Biology subjects

Ben Longdon

Publications and source records attributed to Ben Longdon.

3 recordsLinked to original sources

bioRxiv2016

Twenty five new viruses associated with the Drosophilidae (Diptera)

Drosophila melanogaster is an important laboratory model for studies of antiviral immunity in invertebrates, and Drosophila species provide a valuable system to study virus host range and host switching. Here we use metagenomic RNA sequencing of ca. 1600 adult flies to discover 25 new RNA viruses associated with six different drosophilid hosts in the wild. We also provide a comprehensive listing of viruses previously reported from the Drosophilidae. The new viruses include Iflaviruses, Rhabdoviruses, Nodaviruses, and Reoviruses, and members of unclassified lineages distantly related to Negeviruses, Sobemoviruses and Poleroviruses, Flaviviridae, and Tombusviridae. Among these are close relatives of Drosophila X virus and Flock House virus, which we find in association with wild Drosophila immigrans. These two viruses are widely used in experimental studies but have not previously been reported to naturally infect Drosophila. Although we detect no new DNA viruses, in D. immigrans and D. obscura we identify sequences very closely related to Armadillidium vulgare Iridescent virus (Invertebrate Iridescent virus 31), bringing the total number of DNA viruses found in the Drosophilidae to three.

Microbiology↗

bioRxiv2015

The discovery, distribution and evolution of viruses associated with Drosophila melanogaster

AO_SCPLOWBSTRACTC_SCPLOWDrosophila melanogaster is a valuable invertebrate model for viral infection and antiviral immunity, and is a focus for studies of insect-virus coevolution. Here we use a metagenomic approach to identify more than 20 previously undetected RNA viruses and a DNA virus associated with wild D. melanogaster. These viruses not only include distant relatives of known insect pathogens, but also novel groups of insect-infecting viruses. By sequencing virus-derived small RNAs we show that the viruses represent active infections of Drosophila. We find that the RNA viruses differ in the number and properties of their small RNAs, and we detect both siRNAs and a novel miRNA from the DNA virus. Analysis of small RNAs also allows us to identify putative viral sequences that lack detectable sequence similarity to known viruses. By surveying >2000 individually collected wild adult Drosophila we show that more than 30% of D. melanogaster carry a detectable virus, and more than 6% carry multiple viruses. However, despite a high prevalence of the Wolbachia endosymbiont--which is known to be protective against virus infections in Drosophila--we were unable to detect any relationship between the presence of Wolbachia and the presence of any virus. Using publicly available RNA-seq datasets we show that the community of viruses in Drosophila laboratories is very different from that seen in the wild, but that some of the newly discovered viruses are nevertheless widespread in laboratory lines and are ubiquitous in cell culture. By sequencing viruses from individual wild-collected flies we show that some viruses are shared between D. melanogaster and D. simulans. Our results provide an essential evolutionary and ecological context for host-virus interaction in Drosophila, and the newly reported viral sequences will help develop D. melanogaster further as a model for molecular and evolutionary virus research.\n\nDO_SCPLOWATAC_SCPLOW AO_SCPLOWVAILABILITYC_SCPLOWAll of the relevant data can be found within the paper and its Supporting Information files, with the exception of raw metagenomic sequence data which are deposited at NCBI Sequence Read Archive (SRP056120), and sequence data which are deposited at Genbank (KP714070-KP714108, KP757922-KP757936 and KP757937-KP757993)

Microbiology↗

bioRxiv2015

The evolution, diversity and host associations of rhabdoviruses

Metagenomic studies are leading to the discovery of a hidden diversity of RNA viruses. These new viruses are poorly characterised and new approaches are needed predict the host species these viruses pose a risk to. The rhabdoviruses are a diverse family of RNA viruses that includes important pathogens of humans, animals and plants. We have discovered 32 new rhabdoviruses through a combination of our own RNA sequencing of insects and searching public sequence databases. Combining these with previously known sequences we reconstructed the phylogeny of 195 rhabdovirus sequences, and produced the most in depth analysis of the family to date. In most cases we know nothing about the biology of the viruses beyond the host they were identified from, but our dataset provides a powerful phylogenetic approach to predict which are vector-borne viruses and which are specific to vertebrates or arthropods. By reconstructing ancestral and present host states we found that switches between major groups of hosts have occurred rarely during rhabdovirus evolution. This allowed us to propose 76 new likely vector-borne vertebrate viruses among viruses identified from vertebrates or biting insects. Based on currently available data, our analysis suggests it is likely there was a single origin of the known plant viruses and arthropod-borne vertebrate viruses, while vertebrate-specific and arthropod-specific viruses arose at least twice. There are also few transitions between aquatic and terrestrial ecosystems. Viruses also cluster together at a finer scale, with closely related viruses tending to be found in closely related hosts. Our data therefore suggest that throughout their evolution, rhabdoviruses have occasionally jumped between distantly related host species before spreading through related hosts in the same environment. This approach offers a way to predict the most probable biology and key traits of newly discovered viruses.

Evolutionary Biology↗