Virus-derived DNA drives mosquito vector tolerance to arboviral infection

Bertsy A Goic (1) , Kenneth A Stapleford (2) , Lionel A Frangeul (1) , Aurélien J Doucet (3) , Valérie A Gausson (1) , Hervé A Blanc (1, 2) , Nidia J Schemmel-Jofre (1) , Gael A Cristofari (4, 3) , Louis A Lambrechts (5) , Marco Vignuzzi (2) , Maria-Carla P Saleh (1)

1 Virus et Interférence ARN - Viruses and RNA Interference
2 Populations virales et Pathogenèse - Viral Populations and Pathogenesis
3 IRCAN - Institut de Recherche sur le Cancer et le Vieillissement
4 UNS - Université Nice Sophia Antipolis (1965 - 2019)
5 IVI - Interactions Virus-Insectes

Mosquitoes develop long-lasting viral infections without substantial deleterious effects, despite high viral loads. This makes mosquitoes efficient vectors for emerging viral diseases with enormous burden on public health. How mosquitoes resist and/or tolerate these viruses is poorly understood. Here we show that two species of Aedes mosquitoes infected with two arboviruses from distinct families (dengue or chikungunya) generate a viral-derived DNA (vDNA) that is essential for mosquito survival and viral tolerance. Inhibition of vDNA formation leads to extreme susceptibility to viral infections, reduction of viral small RNAs due to an impaired immune response, and loss of viral tolerance. Our results highlight an essential role of vDNA in viral tolerance that allows mosquito survival and thus may be important for arbovirus dissemination and transmission. Elucidating the mechanisms of mosquito tolerance to arbovirus infection paves the way to conceptualize new antivectorial strategies to selectively eliminate arbovirus-infected mosquitoes.

Mots clés: viral infections; mosquitoes; arbovirus infection; RNAs; DNA; Innate immunity; Virus–host interactions

Domaines: Virologie

Bertsy A Goic, Kenneth A Stapleford, Lionel A Frangeul, Aurélien J Doucet, Valérie A Gausson, et al.. Virus-derived DNA drives mosquito vector tolerance to arboviral infection. Nature Communications, 2016, 7, pp.article number 12410. ⟨10.1038/ncomms12410⟩. ⟨pasteur-01377742⟩