Global transcriptome analysis of Aedes aegypti mosquitoes in response to Zika virus infection

Zika virus (ZIKV) of the Flaviviridae family is a recently emerged mosquito-borne virus that has been implicated in the surge of the number of microcephaly instances in south America. The virus is transmitted mainly by the mosquito Aedes aegypti that also vectors dengue virus. Considering rather recent rapid spread of the virus and its declaration as a global health emergency by the World Health Organization, little is known about the interactions of the virus with the mosquito vector. In this study, we investigated the transcriptome profiles of whole Ae. aegypti mosquitoes in response to ZIKV infection at 2, 7 and 14 days post-infection using deep sequencing. Results showed a large number of transcripts were altered at each time point following infection, but 18 transcripts were commonly changed at the three time points. The outcomes provide a basic understanding of Ae. aegypti responses to ZIKV and help determining host factors involved in replication or anti-viral response against the virus. Overall design: Briefly, 4-6 day old female Ae. aegypti (Galveston strain) were orally infected with ZIKV (Mex 1-7 strain) at 2 x 105 focus forming units (FFU)/ml) in a sheep blood meal (Colorado Serum Company). Infected mosquitoes were collected at 2, 7 and 14 days post-infection (dpi) from which RNA was extracted using the mirVana RNA extraction kit (Life Technologies) applying the protocol for extraction of total RNA. Viral infection in mosquitoes was confirmed by Taqman qPCR on ABI StepOnePlus machine (Applied Biosystems). For all time points, three independent pools were used to create libraries for infected and uninfected samples. Uninfected mosquitoes were fed with ZIKV-free blood, collected at the same time points and processed as above.