Title

Discovering the Aedes Mosquito Virome: Building the First Mosquito Virome Atlas

Abstract

Aedes aegypti poses a significant public health threat, as it is the primary vector of dengue virus and other arboviruses such as zika virus, chikungunya and yellow fever virus. This concern has become more prescient over the past decades as A. aegypti has undergone a massive increase its geographic reach (1,2). As a result, Dengue fever has become the fastest-growing vector-borne disease worldwide, causing an estimated 400 million new infections anually (1,3–5). Interestingly however, the incidence of arbovirus infection is not directly correlated with mosquito abundance (6). Instead, the infections are subject to multiple environmental and physiological factors. 

One such under explored factor is the insect-specific viruses (ISVs) in Aedes mosquitoes (7–11). Despite recent evidence that interactions among viruses in the vector insect may affect transmission (12), little effort has gone into identifying ISVs that could reduce arbovirus transmission. During this summer research fellowship, you will conduct metagenomic analyses to identify ISVs that may be able to disrupt the transmission of arboviruses in the host insect. 

You will first use RNA-seq data from body-part-specific tissue samples of A. aegypti to map the spatial distribution of viruses in A. aegypti: This will be the first ‘ViromAtlas’ of its kind. With this map, we will aim to identify viruses that may co-occur and therefore potentially compete with medically significant arboviruses such as dengue, chikungunya, zika and yellow fever virus. The project will be entirely computational and therefore offers students a great opportunity to learn or improve skills in various bioinformatics tools and R.

Required Knowledge

• A very rudimentary understanding of R programming or statistics is required
• While we welcome applicants with experience in bioinformatics it is not necessary.

Supervisors 

Day-to-day supervisor: Sandy Hickson (sggh2@cam.ac.uk)

Co-supervisor:  Frank Jiggins (fmj1001@cam.ac.uk)

Department of Genetics

References

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9. Ramos-Nino ME, Fitzpatrick DM, Tighe S, Eckstrom KM, Hattaway LM, Hsueh AN, et al. High prevalence of Phasi Charoen-like virus from wild-caught Aedes aegypti in Grenada, W.I. as revealed by metagenomic analysis. PLoS One. 2020 Jan 31;15(1):e0227998.
10. Zakrzewski M, Rašić G, Darbro J, Krause L, Poo YS, Filipović I, et al. Mapping the virome in wild-caught Aedes aegypti from Cairns and Bangkok. Sci Rep. 2018 Mar 16;8(1):4690.
11. Shi C, Beller L, Deboutte W, Yinda KC, Delang L, Vega-Rúa A, et al. Stable distinct core eukaryotic viromes in different mosquito species from Guadeloupe, using single mosquito viral metagenomics. Microbiome. 2019 Aug 28;7(1):121.
12. Olmo RP, Todjro YMH, Aguiar ERGR, de Almeida JPP, Ferreira FV, Armache JN, et al. Mosquito vector competence for dengue is modulated by insect-specific viruses. Nat Microbiol. 2023 Jan;8(1):135–49.