RNA-Seq for detecting viral agents in wild-caught insects

Mosquito-borne infectious diseases pose a severe threat to public health in many areas of the world. Efficient approaches are required for screening wild mosquito populations to detect known and unknown pathogens.

Recent advances in high throughput sequencing technology have made its application easier, cheaper, more convenient and more efficient allowing it to evolve into a powerful tool for identification of novel human pathogens. Due to the short length of the small RNA molecules, sequencing is even faster and cheaper than standard high throughput sequencing using longer DNA or RNA fragments. This makes high throughput sequencing of small RNA an attractive method for pathogen detection in plants and insects.

Researchers at the Beijing Institute of Microbiology and Epidemiology and the Yunnan Institute of Endemic Disease Control and Prevention explored the use of Next Generation RNA Sequencing to identify viral agents in wild-caught mosquitoes. They extracted total RNA from different mosquito species from South China which was then subjected to small RNA sequencing.

They identified a non-enveloped single-stranded DNA densovirus in the wild-caught Culex pipiens molestus mosquitoes. Additionally they found some small RNAs in the reverse repeat regions of the viral 5’- and 3’ -untranslated regions where no transcripts were expected.

This study is the first to explore the application of convenient small RNA high throughput sequencing for virus discovery in wild-caught vectors. These results suggest that small RNA sequencing is able to identify not only RNA viruses, but also DNA viruses in wild-caught mosquitoes, obviating the need for culture-based virus isolation or for prior knowledge of the etiologic agent.

  • Ma M, Huang Y, Gong Z, Zhuang L, Li C, et al. (2011) Discovery of DNA Viruses in Wild-Caught Mosquitoes Using Small RNA High throughput Sequencing. PLoS ONE 6(9), e24758. [article]