Transcriptome Analysis of Aedes aegypti Aag2 Cells in Response to Dengue Virus-2 Infection

Abstract

Background: Dengue virus (DENV) is a flavivirus transmitted by mosquitoes that is prevalent in tropical and subtropical countries and has four serotypes (DENV1-4). Aedes aegypti, as the main transmission vector of DENV, exhibits strong infectivity and transmission. With the aim of obtaining a better understanding of the Ae. aegypti-DENV interaction, the transcriptome changes in DENV-2-infected Aag2 cells were studied to describe the immune responses of mosquitoes using the Ae. aegypti Aag2 cell line as a model.

Methods: RNAseq technology was used to sequence the transcripts of the Ae. aegypti Aag2 cell line before and after infection with DENV-2. A bioinformatics analysis was then performed to assess the biological functions of the differentially expressed genes, and the sequencing data were verified by quantitative reverse transcription-polymerase chain reaction (qRT-PCR).

Results: The transcriptome analysis generated 8866 unigenes that were found in both groups, 225 unigenes that were only found in the infection group, and 683 unigenes that only existed in the control group. A total of 1199 differentially expressed genes, including 1014 upregulated and 185 downregulated genes, were identified. The bioinformatics analysis showed that the differentially expressed genes were mainly involved in the longevity regulating pathway, circadian rhythm, DNA replication, and peroxisome, purine, pyrimidine, and drug metabolism. The qRT-PCR verification results showed the same trend, which confirmed that the expression of the differentially expressed genes had changed and that the transcriptome sequencing data were reliable.

Conclusions: This study investigated the changes in the transcriptome levels in the DENV-2-infected Ae. aegypti Aag2 cell line, which provides a faster and effective method for discovering genes related to Ae. aegypti pathogen susceptibility. The findings provide basic data and directions for further research on the complex mechanism underlying host-pathogen interactions.