To Investigate the Role of Species-Associated Splicing Regulators in Influenza Virus Replication

Cross-species infection of influenza A virus is the emergence of a new endemic or pandemic influenza. However, the mechanisms of cross-species infection have not been well characterized. In our previous studies, we found that the alternative splicing of M1 mRNA of influenza A virus is species-associated. In human cells, M1 mRNA is spliced to efficiently generate M2 mRNA, leading to the production of sufficient M2 ion channel protein. M2 protein that contains highly conserved sequences in viruses appears to be not only needed for efficient viral infection, but also associates with viral pathogenicity. Therefore, M2 protein may be a target for developing vaccine or antiviral agents. In contrast to the situation in human cells, M1 mRNA is majorly unspliced in avian cells. Therefore, we suggest that species-associated regulators promote the alternative splicing of M1 mRNA in human cells. Moreover, these factors may play a crucial role in cross-species infection, including the enhancement of viral adaptation or pathogenicity. In this proposal, the splicing regulators (including proteins and regulatory RNAs) will be identified using a proteomic approach and RNA sequencing. The effect of these host cell factors on M1 mRNA splicing will also be investigated. This project will reveal the mechanism of how species-associated splicing factors regulate viral replication, which may stimulate the development of preventive and therapeutic strategies for alleviating disease severity in cross-species infections. The three specific aims of the proposal are summarized as follows: (1) To identify species-associated factors that regulate the alternative splicing of M1 mRNA using MS2-tagged M1 mRNA affinity purification. (2) To examine whether these regulators interact with M1 mRNA and promote M1 mRNA splicing. (3) To use a loss-of-function mutant virus to explore the impacts of these regulators on viral replication and viral-induced pathogenicity.

Project ID:PC10901-1627
External Project ID:MOST107-2320-B182-023-MY3