Analysing inhibition of dengue virus in Wolbachia-infected mosquito cells following the removal of Wolbachia

Wolbachia pipientis is known to block replication of positive sense RNA viruses. Previously, we created an Aedes aegypti Aag2 cell line (Aag2.wAlbB) transinfected with the wAlbB strain of Wolbachia and a matching tetracycline-cured Aag2.tet cell line. While dengue virus (DENV) was blocked in Aag2.wAlbB cells, we found significant inhibition of DENV in Aag2.tet cells. RNA-Seq analysis of the cells confirmed removal of Wolbachia and lack of expression of Wolbachia genes that could have been due to lateral gene transfer in Aag2.tet cells. However, we noticed a substantial increase in the abundance of phasi charoen-like virus (PCLV) in Aag2.tet cells. When RNAi was used to reduce the PCLV levels, DENV replication was significantly increased. Further, we found significant changes in the expression of antiviral and proviral genes in Aag2.tet cells. Overall, the results reveal an antagonistic interaction between DENV and PCLV and how PCLV-induced changes could contribute to DENV inhibition.

Automated summary

Wolbachia pipientis can block replication of positive sense RNA viruses. A study on Aedes aegypti cell lines revealed that dengue virus (DENV) was blocked in cells carrying the wAlbB strain of Wolbachia, but significantly inhibited in tetracycline-cured cells. RNA-Seq analysis showed the removal of Wolbachia and absence of Wolbachia gene expression in tetracycline-cured cells, while the abundance of phasi charoen-like virus (PCLV) was increased. Decreasing PCLV levels through RNAi resulted in increased DENV replication, indicating an antagonistic interaction between DENV and PCLV.